fb83200047149ff6635efef146b92fd57e847c53
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005, 2006 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.166 2006/05/16 06:46:37 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 // calculated from config->l2tp_mtu
79 uint16_t MRU = 0; // PPP MRU
80 uint16_t MSS = 0; // TCP MSS
81
82 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
83 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
84
85 static void *ip_hash[256]; // Mapping from IP address to session structures.
86 struct ipv6radix {
87 int sess;
88 struct ipv6radix *branch;
89 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
90
91 // Traffic counters.
92 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
93 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
94 uint32_t eth_tx = 0;
95
96 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
97 time_t time_now = 0; // Current time in seconds since epoch.
98 static char time_now_string[64] = {0}; // Current time as a string.
99 static int time_changed = 0; // time_now changed
100 char main_quit = 0; // True if we're in the process of exiting.
101 static char main_reload = 0; // Re-load pending
102 linked_list *loaded_plugins;
103 linked_list *plugins[MAX_PLUGIN_TYPES];
104
105 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
106 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
107
108 config_descriptt config_values[] = {
109 CONFIG("debug", debug, INT),
110 CONFIG("log_file", log_filename, STRING),
111 CONFIG("pid_file", pid_file, STRING),
112 CONFIG("random_device", random_device, STRING),
113 CONFIG("l2tp_secret", l2tp_secret, STRING),
114 CONFIG("l2tp_mtu", l2tp_mtu, INT),
115 CONFIG("ppp_restart_time", ppp_restart_time, INT),
116 CONFIG("ppp_max_configure", ppp_max_configure, INT),
117 CONFIG("ppp_max_failure", ppp_max_failure, INT),
118 CONFIG("primary_dns", default_dns1, IPv4),
119 CONFIG("secondary_dns", default_dns2, IPv4),
120 CONFIG("primary_radius", radiusserver[0], IPv4),
121 CONFIG("secondary_radius", radiusserver[1], IPv4),
122 CONFIG("primary_radius_port", radiusport[0], SHORT),
123 CONFIG("secondary_radius_port", radiusport[1], SHORT),
124 CONFIG("radius_accounting", radius_accounting, BOOL),
125 CONFIG("radius_interim", radius_interim, INT),
126 CONFIG("radius_secret", radiussecret, STRING),
127 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
128 CONFIG("radius_dae_port", radius_dae_port, SHORT),
129 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
130 CONFIG("guest_account", guest_user, STRING),
131 CONFIG("bind_address", bind_address, IPv4),
132 CONFIG("peer_address", peer_address, IPv4),
133 CONFIG("send_garp", send_garp, BOOL),
134 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
135 CONFIG("throttle_buckets", num_tbfs, INT),
136 CONFIG("accounting_dir", accounting_dir, STRING),
137 CONFIG("dump_speed", dump_speed, BOOL),
138 CONFIG("multi_read_count", multi_read_count, INT),
139 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
140 CONFIG("lock_pages", lock_pages, BOOL),
141 CONFIG("icmp_rate", icmp_rate, INT),
142 CONFIG("packet_limit", max_packets, INT),
143 CONFIG("cluster_address", cluster_address, IPv4),
144 CONFIG("cluster_interface", cluster_interface, STRING),
145 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
146 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
147 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
148 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
149 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
150 { NULL, 0, 0, 0 },
151 };
152
153 static char *plugin_functions[] = {
154 NULL,
155 "plugin_pre_auth",
156 "plugin_post_auth",
157 "plugin_packet_rx",
158 "plugin_packet_tx",
159 "plugin_timer",
160 "plugin_new_session",
161 "plugin_kill_session",
162 "plugin_control",
163 "plugin_radius_response",
164 "plugin_radius_reset",
165 "plugin_radius_account",
166 "plugin_become_master",
167 "plugin_new_session_master",
168 };
169
170 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
171
172 // Counters for shutdown sessions
173 static sessiont shut_acct[8192];
174 static sessionidt shut_acct_n = 0;
175
176 tunnelt *tunnel = NULL; // Array of tunnel structures.
177 bundlet *bundle = NULL; // Array of bundle structures.
178 fragmentationt *frag = NULL; // Array of fragmentation structures.
179 sessiont *session = NULL; // Array of session structures.
180 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
181 radiust *radius = NULL; // Array of radius structures.
182 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
183 ip_filtert *ip_filters = NULL; // Array of named filters.
184 static controlt *controlfree = 0;
185 struct Tstats *_statistics = NULL;
186 #ifdef RINGBUFFER
187 struct Tringbuffer *ringbuffer = NULL;
188 #endif
189
190 static void cache_ipmap(in_addr_t ip, int s);
191 static void uncache_ipmap(in_addr_t ip);
192 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
193 static void free_ip_address(sessionidt s);
194 static void dump_acct_info(int all);
195 static void sighup_handler(int sig);
196 static void shutdown_handler(int sig);
197 static void sigchild_handler(int sig);
198 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
199 static void update_config(void);
200 static void read_config_file(void);
201 static void initplugins(void);
202 static int add_plugin(char *plugin_name);
203 static int remove_plugin(char *plugin_name);
204 static void plugins_done(void);
205 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
206 static tunnelidt new_tunnel(void);
207 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
208 static void bundleclear(bundleidt b);
209
210 // on slaves, alow BGP to withdraw cleanly before exiting
211 #define QUIT_DELAY 5
212
213 // quit actions (master)
214 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
215 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
216
217 // return internal time (10ths since process startup), set f if given
218 // as a side-effect sets time_now, and time_changed
219 static clockt now(double *f)
220 {
221 struct timeval t;
222 gettimeofday(&t, 0);
223 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
224 if (t.tv_sec != time_now)
225 {
226 time_now = t.tv_sec;
227 time_changed++;
228 }
229 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
230 }
231
232 // work out a retry time based on try number
233 // This is a straight bounded exponential backoff.
234 // Maximum re-try time is 32 seconds. (2^5).
235 clockt backoff(uint8_t try)
236 {
237 if (try > 5) try = 5; // max backoff
238 return now(NULL) + 10 * (1 << try);
239 }
240
241
242 //
243 // Log a debug message. Typically called via the LOG macro
244 //
245 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
246 {
247 static char message[65536] = {0};
248 va_list ap;
249
250 #ifdef RINGBUFFER
251 if (ringbuffer)
252 {
253 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
254 ringbuffer->tail = 0;
255 if (ringbuffer->tail == ringbuffer->head)
256 if (++ringbuffer->head >= RINGBUFFER_SIZE)
257 ringbuffer->head = 0;
258
259 ringbuffer->buffer[ringbuffer->tail].level = level;
260 ringbuffer->buffer[ringbuffer->tail].session = s;
261 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
262 va_start(ap, format);
263 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
264 va_end(ap);
265 }
266 #endif
267
268 if (config->debug < level) return;
269
270 va_start(ap, format);
271 vsnprintf(message, sizeof(message), format, ap);
272
273 if (log_stream)
274 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
275 else if (syslog_log)
276 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
277
278 va_end(ap);
279 }
280
281 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
282 {
283 int i, j;
284 const uint8_t *d = data;
285
286 if (config->debug < level) return;
287
288 // No support for _log_hex to syslog
289 if (log_stream)
290 {
291 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
292 setvbuf(log_stream, NULL, _IOFBF, 16384);
293
294 for (i = 0; i < maxsize; )
295 {
296 fprintf(log_stream, "%4X: ", i);
297 for (j = i; j < maxsize && j < (i + 16); j++)
298 {
299 fprintf(log_stream, "%02X ", d[j]);
300 if (j == i + 7)
301 fputs(": ", log_stream);
302 }
303
304 for (; j < i + 16; j++)
305 {
306 fputs(" ", log_stream);
307 if (j == i + 7)
308 fputs(": ", log_stream);
309 }
310
311 fputs(" ", log_stream);
312 for (j = i; j < maxsize && j < (i + 16); j++)
313 {
314 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
315 fputc(d[j], log_stream);
316 else
317 fputc('.', log_stream);
318
319 if (j == i + 7)
320 fputs(" ", log_stream);
321 }
322
323 i = j;
324 fputs("\n", log_stream);
325 }
326
327 fflush(log_stream);
328 setbuf(log_stream, NULL);
329 }
330 }
331
332 // update a counter, accumulating 2^32 wraps
333 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
334 {
335 uint32_t new = *counter + delta;
336 if (new < *counter)
337 (*wrap)++;
338
339 *counter = new;
340 }
341
342 // initialise the random generator
343 static void initrandom(char *source)
344 {
345 static char path[sizeof(config->random_device)] = "*undefined*";
346
347 // reinitialise only if we are forced to do so or if the config has changed
348 if (source && !strncmp(path, source, sizeof(path)))
349 return;
350
351 // close previous source, if any
352 if (rand_fd >= 0)
353 close(rand_fd);
354
355 rand_fd = -1;
356
357 if (source)
358 {
359 // register changes
360 snprintf(path, sizeof(path), "%s", source);
361
362 if (*path == '/')
363 {
364 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
365 if (rand_fd < 0)
366 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
367 path, strerror(errno));
368 }
369 }
370 }
371
372 // fill buffer with random data
373 void random_data(uint8_t *buf, int len)
374 {
375 int n = 0;
376
377 CSTAT(random_data);
378 if (rand_fd >= 0)
379 {
380 n = read(rand_fd, buf, len);
381 if (n >= len) return;
382 if (n < 0)
383 {
384 if (errno != EAGAIN)
385 {
386 LOG(0, 0, 0, "Error reading from random source: %s\n",
387 strerror(errno));
388
389 // fall back to rand()
390 initrandom(NULL);
391 }
392
393 n = 0;
394 }
395 }
396
397 // append missing data
398 while (n < len)
399 // not using the low order bits from the prng stream
400 buf[n++] = (rand() >> 4) & 0xff;
401 }
402
403 // Add a route
404 //
405 // This adds it to the routing table, advertises it
406 // via BGP if enabled, and stuffs it into the
407 // 'sessionbyip' cache.
408 //
409 // 'ip' and 'mask' must be in _host_ order.
410 //
411 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
412 {
413 struct rtentry r;
414 int i;
415
416 if (!mask) mask = 0xffffffff;
417
418 ip &= mask; // Force the ip to be the first one in the route.
419
420 memset(&r, 0, sizeof(r));
421 r.rt_dev = config->tundevice;
422 r.rt_dst.sa_family = AF_INET;
423 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
424 r.rt_gateway.sa_family = AF_INET;
425 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
426 r.rt_genmask.sa_family = AF_INET;
427 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
428 r.rt_flags = (RTF_UP | RTF_STATIC);
429 if (gw)
430 r.rt_flags |= RTF_GATEWAY;
431 else if (mask == 0xffffffff)
432 r.rt_flags |= RTF_HOST;
433
434 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
435 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
436 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
437
438 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
439 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
440
441 #ifdef BGP
442 if (add)
443 bgp_add_route(htonl(ip), htonl(mask));
444 else
445 bgp_del_route(htonl(ip), htonl(mask));
446 #endif /* BGP */
447
448 // Add/Remove the IPs to the 'sessionbyip' cache.
449 // Note that we add the zero address in the case of
450 // a network route. Roll on CIDR.
451
452 // Note that 's == 0' implies this is the address pool.
453 // We still cache it here, because it will pre-fill
454 // the malloc'ed tree.
455
456 if (s)
457 {
458 if (!add) // Are we deleting a route?
459 s = 0; // Caching the session as '0' is the same as uncaching.
460
461 for (i = ip; (i&mask) == (ip&mask) ; ++i)
462 cache_ipmap(i, s);
463 }
464 }
465
466 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
467 {
468 struct in6_rtmsg rt;
469 char ipv6addr[INET6_ADDRSTRLEN];
470
471 if (ifr6fd < 0)
472 {
473 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
474 return;
475 }
476
477 memset(&rt, 0, sizeof(rt));
478
479 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
480 rt.rtmsg_dst_len = prefixlen;
481 rt.rtmsg_metric = 1;
482 rt.rtmsg_flags = RTF_UP;
483 rt.rtmsg_ifindex = tunidx;
484
485 LOG(1, 0, 0, "Route %s %s/%d\n",
486 add ? "add" : "del",
487 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
488 prefixlen);
489
490 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
491 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
492 strerror(errno));
493
494 // FIXME: need to add BGP routing (RFC2858)
495
496 if (s)
497 {
498 if (!add) // Are we deleting a route?
499 s = 0; // Caching the session as '0' is the same as uncaching.
500
501 cache_ipv6map(ip, prefixlen, s);
502 }
503
504 return;
505 }
506
507 // defined in linux/ipv6.h, but tricky to include from user-space
508 // TODO: move routing to use netlink rather than ioctl
509 struct in6_ifreq {
510 struct in6_addr ifr6_addr;
511 __u32 ifr6_prefixlen;
512 unsigned int ifr6_ifindex;
513 };
514
515 //
516 // Set up TUN interface
517 static void inittun(void)
518 {
519 struct ifreq ifr;
520 struct in6_ifreq ifr6;
521 struct sockaddr_in sin = {0};
522 memset(&ifr, 0, sizeof(ifr));
523 ifr.ifr_flags = IFF_TUN;
524
525 tunfd = open(TUNDEVICE, O_RDWR);
526 if (tunfd < 0)
527 { // fatal
528 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
529 exit(1);
530 }
531 {
532 int flags = fcntl(tunfd, F_GETFL, 0);
533 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
534 }
535 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
536 {
537 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
538 exit(1);
539 }
540 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
541 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
542 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
543
544 sin.sin_family = AF_INET;
545 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
546 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
547
548 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
549 {
550 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
551 exit(1);
552 }
553 /* Bump up the qlen to deal with bursts from the network */
554 ifr.ifr_qlen = 1000;
555 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
556 {
557 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
558 exit(1);
559 }
560 /* set MTU to modem MRU */
561 ifr.ifr_mtu = MRU;
562 if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
563 {
564 LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
565 exit(1);
566 }
567 ifr.ifr_flags = IFF_UP;
568 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
569 {
570 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
571 exit(1);
572 }
573 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
574 {
575 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
576 exit(1);
577 }
578 tunidx = ifr.ifr_ifindex;
579
580 // Only setup IPv6 on the tun device if we have a configured prefix
581 if (config->ipv6_prefix.s6_addr[0]) {
582 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
583
584 // Link local address is FE80::1
585 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
586 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
587 ifr6.ifr6_addr.s6_addr[1] = 0x80;
588 ifr6.ifr6_addr.s6_addr[15] = 1;
589 ifr6.ifr6_prefixlen = 64;
590 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
591 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
592 {
593 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
594 " %s\n", strerror(errno));
595 }
596
597 // Global address is prefix::1
598 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
599 ifr6.ifr6_addr = config->ipv6_prefix;
600 ifr6.ifr6_addr.s6_addr[15] = 1;
601 ifr6.ifr6_prefixlen = 64;
602 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
603 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
604 {
605 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
606 strerror(errno));
607 }
608 }
609 }
610
611 // set up UDP ports
612 static void initudp(void)
613 {
614 int on = 1;
615 struct sockaddr_in addr;
616
617 // Tunnel
618 memset(&addr, 0, sizeof(addr));
619 addr.sin_family = AF_INET;
620 addr.sin_port = htons(L2TPPORT);
621 addr.sin_addr.s_addr = config->bind_address;
622 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
623 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
624 {
625 int flags = fcntl(udpfd, F_GETFL, 0);
626 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
627 }
628 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
629 {
630 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
631 exit(1);
632 }
633
634 // Control
635 memset(&addr, 0, sizeof(addr));
636 addr.sin_family = AF_INET;
637 addr.sin_port = htons(NSCTL_PORT);
638 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
639 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
640 setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
641 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
642 {
643 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
644 exit(1);
645 }
646
647 // Dynamic Authorization Extensions to RADIUS
648 memset(&addr, 0, sizeof(addr));
649 addr.sin_family = AF_INET;
650 addr.sin_port = htons(config->radius_dae_port);
651 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
652 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
653 setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
654 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
655 {
656 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
657 exit(1);
658 }
659
660 // Intercept
661 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
662 }
663
664 //
665 // Find session by IP, < 1 for not found
666 //
667 // Confusingly enough, this 'ip' must be
668 // in _network_ order. This being the common
669 // case when looking it up from IP packet headers.
670 //
671 // We actually use this cache for two things.
672 // #1. For used IP addresses, this maps to the
673 // session ID that it's used by.
674 // #2. For un-used IP addresses, this maps to the
675 // index into the pool table that contains that
676 // IP address.
677 //
678
679 static int lookup_ipmap(in_addr_t ip)
680 {
681 uint8_t *a = (uint8_t *) &ip;
682 uint8_t **d = (uint8_t **) ip_hash;
683
684 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
685 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
686 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
687
688 return (int) (intptr_t) d[(size_t) *a];
689 }
690
691 static int lookup_ipv6map(struct in6_addr ip)
692 {
693 struct ipv6radix *curnode;
694 int i;
695 int s;
696 char ipv6addr[INET6_ADDRSTRLEN];
697
698 curnode = &ipv6_hash[ip.s6_addr[0]];
699 i = 1;
700 s = curnode->sess;
701
702 while (s == 0 && i < 15 && curnode->branch != NULL)
703 {
704 curnode = &curnode->branch[ip.s6_addr[i]];
705 s = curnode->sess;
706 i++;
707 }
708
709 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
710 inet_ntop(AF_INET6, &ip, ipv6addr,
711 INET6_ADDRSTRLEN),
712 s);
713
714 return s;
715 }
716
717 sessionidt sessionbyip(in_addr_t ip)
718 {
719 int s = lookup_ipmap(ip);
720 CSTAT(sessionbyip);
721
722 if (s > 0 && s < MAXSESSION && session[s].opened)
723 return (sessionidt) s;
724
725 return 0;
726 }
727
728 sessionidt sessionbyipv6(struct in6_addr ip)
729 {
730 int s;
731 CSTAT(sessionbyipv6);
732
733 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
734 (ip.s6_addr[0] == 0xFE &&
735 ip.s6_addr[1] == 0x80 &&
736 ip.s6_addr16[1] == 0 &&
737 ip.s6_addr16[2] == 0 &&
738 ip.s6_addr16[3] == 0)) {
739 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
740 } else {
741 s = lookup_ipv6map(ip);
742 }
743
744 if (s > 0 && s < MAXSESSION && session[s].opened)
745 return s;
746
747 return 0;
748 }
749
750 //
751 // Take an IP address in HOST byte order and
752 // add it to the sessionid by IP cache.
753 //
754 // (It's actually cached in network order)
755 //
756 static void cache_ipmap(in_addr_t ip, int s)
757 {
758 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
759 uint8_t *a = (uint8_t *) &nip;
760 uint8_t **d = (uint8_t **) ip_hash;
761 int i;
762
763 for (i = 0; i < 3; i++)
764 {
765 if (!d[(size_t) a[i]])
766 {
767 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
768 return;
769 }
770
771 d = (uint8_t **) d[(size_t) a[i]];
772 }
773
774 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
775
776 if (s > 0)
777 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
778
779 else if (s == 0)
780 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
781 // else a map to an ip pool index.
782 }
783
784 static void uncache_ipmap(in_addr_t ip)
785 {
786 cache_ipmap(ip, 0); // Assign it to the NULL session.
787 }
788
789 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
790 {
791 int i;
792 int bytes;
793 struct ipv6radix *curnode;
794 char ipv6addr[INET6_ADDRSTRLEN];
795
796 curnode = &ipv6_hash[ip.s6_addr[0]];
797
798 bytes = prefixlen >> 3;
799 i = 1;
800 while (i < bytes) {
801 if (curnode->branch == NULL)
802 {
803 if (!(curnode->branch = calloc(256,
804 sizeof (struct ipv6radix))))
805 return;
806 }
807 curnode = &curnode->branch[ip.s6_addr[i]];
808 i++;
809 }
810
811 curnode->sess = s;
812
813 if (s > 0)
814 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
815 inet_ntop(AF_INET6, &ip, ipv6addr,
816 INET6_ADDRSTRLEN),
817 prefixlen);
818 else if (s == 0)
819 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
820 inet_ntop(AF_INET6, &ip, ipv6addr,
821 INET6_ADDRSTRLEN),
822 prefixlen);
823 }
824
825 //
826 // CLI list to dump current ipcache.
827 //
828 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
829 {
830 char **d = (char **) ip_hash, **e, **f, **g;
831 int i, j, k, l;
832 int count = 0;
833
834 if (CLI_HELP_REQUESTED)
835 return CLI_HELP_NO_ARGS;
836
837 cli_print(cli, "%7s %s", "Sess#", "IP Address");
838
839 for (i = 0; i < 256; ++i)
840 {
841 if (!d[i])
842 continue;
843 e = (char **) d[i];
844 for (j = 0; j < 256; ++j)
845 {
846 if (!e[j])
847 continue;
848 f = (char **) e[j];
849 for (k = 0; k < 256; ++k)
850 {
851 if (!f[k])
852 continue;
853 g = (char **)f[k];
854 for (l = 0; l < 256; ++l)
855 {
856 if (!g[l])
857 continue;
858 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
859 ++count;
860 }
861 }
862 }
863 }
864 cli_print(cli, "%d entries in cache", count);
865 return CLI_OK;
866 }
867
868
869 // Find session by username, 0 for not found
870 // walled garden users aren't authenticated, so the username is
871 // reasonably useless. Ignore them to avoid incorrect actions
872 //
873 // This is VERY inefficent. Don't call it often. :)
874 //
875 sessionidt sessionbyuser(char *username)
876 {
877 int s;
878 CSTAT(sessionbyuser);
879
880 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
881 {
882 if (!session[s].opened)
883 continue;
884
885 if (session[s].walled_garden)
886 continue; // Skip walled garden users.
887
888 if (!strncmp(session[s].user, username, 128))
889 return s;
890
891 }
892 return 0; // Not found.
893 }
894
895 void send_garp(in_addr_t ip)
896 {
897 int s;
898 struct ifreq ifr;
899 uint8_t mac[6];
900
901 s = socket(PF_INET, SOCK_DGRAM, 0);
902 if (s < 0)
903 {
904 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
905 return;
906 }
907 memset(&ifr, 0, sizeof(ifr));
908 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
909 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
910 {
911 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
912 close(s);
913 return;
914 }
915 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
916 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
917 {
918 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
919 close(s);
920 return;
921 }
922 close(s);
923 sendarp(ifr.ifr_ifindex, mac, ip);
924 }
925
926 static sessiont *sessiontbysessionidt(sessionidt s)
927 {
928 if (!s || s >= MAXSESSION) return NULL;
929 return &session[s];
930 }
931
932 static sessionidt sessionidtbysessiont(sessiont *s)
933 {
934 sessionidt val = s-session;
935 if (s < session || val >= MAXSESSION) return 0;
936 return val;
937 }
938
939 // actually send a control message for a specific tunnel
940 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
941 {
942 struct sockaddr_in addr;
943
944 CSTAT(tunnelsend);
945
946 if (!t)
947 {
948 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
949 STAT(tunnel_tx_errors);
950 return;
951 }
952
953 if (!tunnel[t].ip)
954 {
955 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
956 STAT(tunnel_tx_errors);
957 return;
958 }
959
960 memset(&addr, 0, sizeof(addr));
961 addr.sin_family = AF_INET;
962 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
963 addr.sin_port = htons(tunnel[t].port);
964
965 // sequence expected, if sequence in message
966 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
967
968 // If this is a control message, deal with retries
969 if (*buf & 0x80)
970 {
971 tunnel[t].last = time_now; // control message sent
972 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
973 if (tunnel[t].try)
974 {
975 STAT(tunnel_retries);
976 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
977 }
978 }
979
980 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
981 {
982 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
983 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
984 STAT(tunnel_tx_errors);
985 return;
986 }
987
988 LOG_HEX(5, "Send Tunnel Data", buf, l);
989 STAT(tunnel_tx_packets);
990 INC_STAT(tunnel_tx_bytes, l);
991 }
992
993 //
994 // Tiny helper function to write data to
995 // the 'tun' device.
996 //
997 int tun_write(uint8_t * data, int size)
998 {
999 return write(tunfd, data, size);
1000 }
1001
1002 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
1003 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
1004 {
1005 int d = (tcp[12] >> 4) * 4;
1006 uint8_t *mss = 0;
1007 uint8_t *opts;
1008 uint8_t *data;
1009 uint16_t orig;
1010 uint32_t sum;
1011
1012 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1013 return;
1014
1015 if (tcp + d > buf + len) // short?
1016 return;
1017
1018 opts = tcp + 20;
1019 data = tcp + d;
1020
1021 while (opts < data)
1022 {
1023 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1024 {
1025 mss = opts + 2;
1026 if (mss + 2 > data) return; // short?
1027 break;
1028 }
1029
1030 if (*opts == 0) return; // end of options
1031 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1032 opts++;
1033 else
1034 opts += opts[1]; // skip over option
1035 }
1036
1037 if (!mss) return; // not found
1038 orig = ntohs(*(uint16_t *) mss);
1039
1040 if (orig <= MSS) return; // mss OK
1041
1042 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1043 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1044 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1045 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1046
1047 // set mss
1048 *(int16_t *) mss = htons(MSS);
1049
1050 // adjust checksum (see rfc1141)
1051 sum = orig + (~MSS & 0xffff);
1052 sum += ntohs(*(uint16_t *) (tcp + 16));
1053 sum = (sum & 0xffff) + (sum >> 16);
1054 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1055 }
1056
1057 void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra)
1058 {
1059 uint16_t proto;
1060 if (extra) {
1061 // Skip the four extra bytes
1062 p += 4;
1063 l -= 4;
1064 }
1065
1066 // Process this frame
1067 if (*p & 1)
1068 {
1069 proto = *p++;
1070 l--;
1071 }
1072 else
1073 {
1074 proto = ntohs(*(uint16_t *) p);
1075 p += 2;
1076 l -= 2;
1077 }
1078 if (proto == PPPIP)
1079 {
1080 if (session[s].die)
1081 {
1082 LOG(4, s, t, "MPPP: Session %u is closing. Don't process PPP packets\n", s);
1083 return; // closing session, PPP not processed
1084 }
1085 session[s].last_packet = time_now;
1086 processipin(s, t, p, l);
1087 }
1088 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
1089 {
1090 if (session[s].die)
1091 {
1092 LOG(4, s, t, "MPPP: Session %u is closing. Don't process PPP packets\n", s);
1093 return; // closing session, PPP not processed
1094 }
1095
1096 session[s].last_packet = time_now;
1097 processipv6in(s, t, p, l);
1098 }
1099 else
1100 {
1101 LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto);
1102 }
1103 }
1104
1105 // process outgoing (to tunnel) IP
1106 //
1107 static void processipout(uint8_t *buf, int len)
1108 {
1109 sessionidt s;
1110 sessiont *sp;
1111 tunnelidt t;
1112 in_addr_t ip;
1113
1114 uint8_t *data = buf; // Keep a copy of the originals.
1115 int size = len;
1116
1117 uint8_t b1[MAXETHER + 20];
1118 uint8_t b2[MAXETHER + 20];
1119
1120 CSTAT(processipout);
1121
1122 if (len < MIN_IP_SIZE)
1123 {
1124 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1125 STAT(tun_rx_errors);
1126 return;
1127 }
1128 if (len >= MAXETHER)
1129 {
1130 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1131 STAT(tun_rx_errors);
1132 return;
1133 }
1134
1135 // Skip the tun header
1136 buf += 4;
1137 len -= 4;
1138
1139 // Got an IP header now
1140 if (*(uint8_t *)(buf) >> 4 != 4)
1141 {
1142 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1143 return;
1144 }
1145
1146 ip = *(uint32_t *)(buf + 16);
1147 if (!(s = sessionbyip(ip)))
1148 {
1149 // Is this a packet for a session that doesn't exist?
1150 static int rate = 0; // Number of ICMP packets we've sent this second.
1151 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1152
1153 if (last != time_now)
1154 {
1155 last = time_now;
1156 rate = 0;
1157 }
1158
1159 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1160 {
1161 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1162 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1163 config->bind_address ? config->bind_address : my_address, buf, len);
1164 }
1165 return;
1166 }
1167 t = session[s].tunnel;
1168 sp = &session[s];
1169
1170 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1171 if (config->max_packets > 0)
1172 {
1173 if (sess_local[s].last_packet_out == TIME)
1174 {
1175 int max = config->max_packets;
1176
1177 // All packets for throttled sessions are handled by the
1178 // master, so further limit by using the throttle rate.
1179 // A bit of a kludge, since throttle rate is in kbps,
1180 // but should still be generous given our average DSL
1181 // packet size is 200 bytes: a limit of 28kbps equates
1182 // to around 180 packets per second.
1183 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1184 max = sp->throttle_out;
1185
1186 if (++sess_local[s].packets_out > max)
1187 {
1188 sess_local[s].packets_dropped++;
1189 return;
1190 }
1191 }
1192 else
1193 {
1194 if (sess_local[s].packets_dropped)
1195 {
1196 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1197 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1198 sess_local[s].packets_dropped, sess_local[s].packets_out,
1199 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1200 sp->user);
1201 }
1202
1203 sess_local[s].last_packet_out = TIME;
1204 sess_local[s].packets_out = 1;
1205 sess_local[s].packets_dropped = 0;
1206 }
1207 }
1208
1209 // run access-list if any
1210 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1211 return;
1212
1213 // adjust MSS on SYN and SYN,ACK packets with options
1214 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1215 {
1216 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1217 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1218 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1219 }
1220
1221 if (sp->tbf_out)
1222 {
1223 // Are we throttling this session?
1224 if (config->cluster_iam_master)
1225 tbf_queue_packet(sp->tbf_out, data, size);
1226 else
1227 master_throttle_packet(sp->tbf_out, data, size);
1228 return;
1229 }
1230
1231 if (sp->walled_garden && !config->cluster_iam_master)
1232 {
1233 // We are walled-gardening this
1234 master_garden_packet(s, data, size);
1235 return;
1236 }
1237
1238 // Add on L2TP header
1239 {
1240 bundleidt bid = 0;
1241 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1242 {
1243 bid = session[s].bundle;
1244 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1245 LOG(4, s, t, "MPPP: (1)Session number becomes: %u\n", s);
1246 if (len > 256)
1247 {
1248 // Partition the packet to 2 fragments
1249 uint32_t frag1len = len / 2;
1250 uint32_t frag2len = len - frag1len;
1251 uint8_t *p = makeppp(b1, sizeof(b1), buf, frag1len, s, t, PPPIP, 0, bid, MP_BEGIN);
1252 uint8_t *q;
1253
1254 if (!p) return;
1255 tunnelsend(b1, frag1len + (p-b1), t); // send it...
1256 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1257 LOG(4, s, t, "MPPP: (2)Session number becomes: %u\n", s);
1258 q = makeppp(b2, sizeof(b2), buf+frag1len, frag2len, s, t, PPPIP, 0, bid, MP_END);
1259 if (!q) return;
1260 tunnelsend(b2, frag2len + (q-b2), t); // send it...
1261 }
1262 else {
1263 // Send it as one frame
1264 uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS);
1265 if (!p) return;
1266 tunnelsend(b1, len + (p-b1), t); // send it...
1267 }
1268 }
1269 else
1270 {
1271 uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, 0, 0);
1272 if (!p) return;
1273 tunnelsend(b1, len + (p-b1), t); // send it...
1274 }
1275 }
1276
1277 // Snooping this session, send it to intercept box
1278 if (sp->snoop_ip && sp->snoop_port)
1279 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1280
1281 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1282 sp->cout_delta += len;
1283 sp->pout++;
1284 udp_tx += len;
1285
1286 sess_local[s].cout += len; // To send to master..
1287 sess_local[s].pout++;
1288 }
1289
1290 // process outgoing (to tunnel) IPv6
1291 //
1292 static void processipv6out(uint8_t * buf, int len)
1293 {
1294 sessionidt s;
1295 sessiont *sp;
1296 tunnelidt t;
1297 in_addr_t ip;
1298 struct in6_addr ip6;
1299
1300 uint8_t *data = buf; // Keep a copy of the originals.
1301 int size = len;
1302
1303 uint8_t b[MAXETHER + 20];
1304
1305 CSTAT(processipv6out);
1306
1307 if (len < MIN_IP_SIZE)
1308 {
1309 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1310 STAT(tunnel_tx_errors);
1311 return;
1312 }
1313 if (len >= MAXETHER)
1314 {
1315 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1316 STAT(tunnel_tx_errors);
1317 return;
1318 }
1319
1320 // Skip the tun header
1321 buf += 4;
1322 len -= 4;
1323
1324 // Got an IP header now
1325 if (*(uint8_t *)(buf) >> 4 != 6)
1326 {
1327 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1328 return;
1329 }
1330
1331 ip6 = *(struct in6_addr *)(buf+24);
1332 s = sessionbyipv6(ip6);
1333
1334 if (s == 0)
1335 {
1336 ip = *(uint32_t *)(buf + 32);
1337 s = sessionbyip(ip);
1338 }
1339
1340 if (s == 0)
1341 {
1342 // Is this a packet for a session that doesn't exist?
1343 static int rate = 0; // Number of ICMP packets we've sent this second.
1344 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1345
1346 if (last != time_now)
1347 {
1348 last = time_now;
1349 rate = 0;
1350 }
1351
1352 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1353 {
1354 // FIXME: Should send icmp6 host unreachable
1355 }
1356 return;
1357 }
1358 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1359 {
1360 bundleidt bid = session[s].bundle;
1361 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1362 LOG(3, s, session[s].tunnel, "MPPP: Session number becomes: %u\n", s);
1363 }
1364 t = session[s].tunnel;
1365 sp = &session[s];
1366
1367 // FIXME: add DoS prevention/filters?
1368
1369 if (sp->tbf_out)
1370 {
1371 // Are we throttling this session?
1372 if (config->cluster_iam_master)
1373 tbf_queue_packet(sp->tbf_out, data, size);
1374 else
1375 master_throttle_packet(sp->tbf_out, data, size);
1376 return;
1377 }
1378 else if (sp->walled_garden && !config->cluster_iam_master)
1379 {
1380 // We are walled-gardening this
1381 master_garden_packet(s, data, size);
1382 return;
1383 }
1384
1385 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1386
1387 // Add on L2TP header
1388 {
1389 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6, 0, 0, 0);
1390 if (!p) return;
1391 tunnelsend(b, len + (p-b), t); // send it...
1392 }
1393
1394 // Snooping this session, send it to intercept box
1395 if (sp->snoop_ip && sp->snoop_port)
1396 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1397
1398 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1399 sp->cout_delta += len;
1400 sp->pout++;
1401 udp_tx += len;
1402
1403 sess_local[s].cout += len; // To send to master..
1404 sess_local[s].pout++;
1405 }
1406
1407 //
1408 // Helper routine for the TBF filters.
1409 // Used to send queued data in to the user!
1410 //
1411 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1412 {
1413 sessiont *sp;
1414 tunnelidt t;
1415 in_addr_t ip;
1416
1417 uint8_t b[MAXETHER + 20];
1418
1419 if (len < 0 || len > MAXETHER)
1420 {
1421 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1422 return;
1423 }
1424
1425 // Skip the tun header
1426 buf += 4;
1427 len -= 4;
1428
1429 ip = *(in_addr_t *)(buf + 16);
1430
1431 if (!session[s].ip)
1432 return;
1433
1434 t = session[s].tunnel;
1435 sp = &session[s];
1436
1437 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1438
1439 // Add on L2TP header
1440 {
1441 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP, 0, 0, 0);
1442 if (!p) return;
1443 tunnelsend(b, len + (p-b), t); // send it...
1444 }
1445
1446 // Snooping this session.
1447 if (sp->snoop_ip && sp->snoop_port)
1448 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1449
1450 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1451 sp->cout_delta += len;
1452 sp->pout++;
1453 udp_tx += len;
1454
1455 sess_local[s].cout += len; // To send to master..
1456 sess_local[s].pout++;
1457 }
1458
1459 // add an AVP (16 bit)
1460 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1461 {
1462 uint16_t l = (m ? 0x8008 : 0x0008);
1463 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1464 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1465 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1466 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1467 c->length += 8;
1468 }
1469
1470 // add an AVP (32 bit)
1471 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1472 {
1473 uint16_t l = (m ? 0x800A : 0x000A);
1474 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1475 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1476 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1477 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1478 c->length += 10;
1479 }
1480
1481 // add an AVP (string)
1482 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1483 {
1484 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1485 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1486 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1487 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1488 memcpy(c->buf + c->length + 6, val, strlen(val));
1489 c->length += 6 + strlen(val);
1490 }
1491
1492 // add a binary AVP
1493 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1494 {
1495 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1496 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1497 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1498 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1499 memcpy(c->buf + c->length + 6, val, len);
1500 c->length += 6 + len;
1501 }
1502
1503 // new control connection
1504 static controlt *controlnew(uint16_t mtype)
1505 {
1506 controlt *c;
1507 if (!controlfree)
1508 c = malloc(sizeof(controlt));
1509 else
1510 {
1511 c = controlfree;
1512 controlfree = c->next;
1513 }
1514 assert(c);
1515 c->next = 0;
1516 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1517 c->length = 12;
1518 control16(c, 0, mtype, 1);
1519 return c;
1520 }
1521
1522 // send zero block if nothing is waiting
1523 // (ZLB send).
1524 static void controlnull(tunnelidt t)
1525 {
1526 uint8_t buf[12];
1527 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1528 return;
1529
1530 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1531 *(uint16_t *) (buf + 2) = htons(12); // length
1532 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1533 *(uint16_t *) (buf + 6) = htons(0); // session
1534 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1535 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1536 tunnelsend(buf, 12, t);
1537 }
1538
1539 // add a control message to a tunnel, and send if within window
1540 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1541 {
1542 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1543 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1544 *(uint16_t *) (c->buf + 6) = htons(far); // session
1545 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1546 tunnel[t].ns++; // advance sequence
1547 // link in message in to queue
1548 if (tunnel[t].controlc)
1549 tunnel[t].controle->next = c;
1550 else
1551 tunnel[t].controls = c;
1552
1553 tunnel[t].controle = c;
1554 tunnel[t].controlc++;
1555
1556 // send now if space in window
1557 if (tunnel[t].controlc <= tunnel[t].window)
1558 {
1559 tunnel[t].try = 0; // first send
1560 tunnelsend(c->buf, c->length, t);
1561 }
1562 }
1563
1564 //
1565 // Throttle or Unthrottle a session
1566 //
1567 // Throttle the data from/to through a session to no more than
1568 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1569 // user).
1570 //
1571 // If either value is -1, the current value is retained for that
1572 // direction.
1573 //
1574 void throttle_session(sessionidt s, int rate_in, int rate_out)
1575 {
1576 if (!session[s].opened)
1577 return; // No-one home.
1578
1579 if (!*session[s].user)
1580 return; // User not logged in
1581
1582 if (rate_in >= 0)
1583 {
1584 int bytes = rate_in * 1024 / 8; // kbits to bytes
1585 if (session[s].tbf_in)
1586 free_tbf(session[s].tbf_in);
1587
1588 if (rate_in > 0)
1589 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1590 else
1591 session[s].tbf_in = 0;
1592
1593 session[s].throttle_in = rate_in;
1594 }
1595
1596 if (rate_out >= 0)
1597 {
1598 int bytes = rate_out * 1024 / 8;
1599 if (session[s].tbf_out)
1600 free_tbf(session[s].tbf_out);
1601
1602 if (rate_out > 0)
1603 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1604 else
1605 session[s].tbf_out = 0;
1606
1607 session[s].throttle_out = rate_out;
1608 }
1609 }
1610
1611 // add/remove filters from session (-1 = no change)
1612 void filter_session(sessionidt s, int filter_in, int filter_out)
1613 {
1614 if (!session[s].opened)
1615 return; // No-one home.
1616
1617 if (!*session[s].user)
1618 return; // User not logged in
1619
1620 // paranoia
1621 if (filter_in > MAXFILTER) filter_in = -1;
1622 if (filter_out > MAXFILTER) filter_out = -1;
1623 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1624 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1625
1626 if (filter_in >= 0)
1627 {
1628 if (session[s].filter_in)
1629 ip_filters[session[s].filter_in - 1].used--;
1630
1631 if (filter_in > 0)
1632 ip_filters[filter_in - 1].used++;
1633
1634 session[s].filter_in = filter_in;
1635 }
1636
1637 if (filter_out >= 0)
1638 {
1639 if (session[s].filter_out)
1640 ip_filters[session[s].filter_out - 1].used--;
1641
1642 if (filter_out > 0)
1643 ip_filters[filter_out - 1].used++;
1644
1645 session[s].filter_out = filter_out;
1646 }
1647 }
1648
1649 // start tidy shutdown of session
1650 void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause)
1651 {
1652 int walled_garden = session[s].walled_garden;
1653
1654
1655 CSTAT(sessionshutdown);
1656
1657 if (!session[s].opened)
1658 {
1659 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1660 return; // not a live session
1661 }
1662
1663 if (!session[s].die)
1664 {
1665 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1666 LOG(2, s, session[s].tunnel, "Shutting down session %u: %s\n", s, reason);
1667 run_plugins(PLUGIN_KILL_SESSION, &data);
1668 }
1669
1670 if (session[s].ip && !walled_garden && !session[s].die)
1671 {
1672 // RADIUS Stop message
1673 uint16_t r = radiusnew(s);
1674 if (r)
1675 {
1676 // stop, if not already trying
1677 if (radius[r].state != RADIUSSTOP)
1678 {
1679 radius[r].term_cause = term_cause;
1680 radius[r].term_msg = reason;
1681 radiussend(r, RADIUSSTOP);
1682 }
1683 }
1684 else
1685 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1686
1687 // Save counters to dump to accounting file
1688 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1689 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1690 }
1691
1692 if (session[s].ip)
1693 { // IP allocated, clear and unroute
1694 int r;
1695 int routed = 0;
1696 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1697 {
1698 if ((session[s].ip & session[s].route[r].mask) ==
1699 (session[s].route[r].ip & session[s].route[r].mask))
1700 routed++;
1701
1702 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1703 session[s].route[r].ip = 0;
1704 }
1705
1706 if (session[s].ip_pool_index == -1) // static ip
1707 {
1708 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1709 session[s].ip = 0;
1710 }
1711 else
1712 free_ip_address(s);
1713
1714 // unroute IPv6, if setup
1715 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1716 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1717 }
1718
1719 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1720 throttle_session(s, 0, 0);
1721
1722 if (cdn_result)
1723 { // Send CDN
1724 controlt *c = controlnew(14); // sending CDN
1725 if (cdn_error)
1726 {
1727 uint8_t buf[4];
1728 *(uint16_t *) buf = htons(cdn_result);
1729 *(uint16_t *) (buf+2) = htons(cdn_error);
1730 controlb(c, 1, buf, 4, 1);
1731 }
1732 else
1733 control16(c, 1, cdn_result, 1);
1734
1735 control16(c, 14, s, 1); // assigned session (our end)
1736 controladd(c, session[s].far, session[s].tunnel); // send the message
1737 }
1738
1739 if (!session[s].die)
1740 session[s].die = TIME + 150; // Clean up in 15 seconds
1741
1742 // update filter refcounts
1743 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1744 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1745
1746 // clear PPP state
1747 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1748 sess_local[s].lcp.restart = 0;
1749 sess_local[s].ipcp.restart = 0;
1750 sess_local[s].ipv6cp.restart = 0;
1751 sess_local[s].ccp.restart = 0;
1752
1753 cluster_send_session(s);
1754 }
1755
1756 void sendipcp(sessionidt s, tunnelidt t)
1757 {
1758 uint8_t buf[MAXETHER];
1759 uint8_t *q;
1760
1761 CSTAT(sendipcp);
1762 LOG(3, s, t, "IPCP: send ConfigReq\n");
1763
1764 if (!session[s].unique_id)
1765 {
1766 if (!++last_id) ++last_id; // skip zero
1767 session[s].unique_id = last_id;
1768 }
1769
1770 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP, 0, 0, 0);
1771 if (!q) return;
1772
1773 *q = ConfigReq;
1774 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1775 *(uint16_t *) (q + 2) = htons(10); // packet length
1776 q[4] = 3; // ip address option
1777 q[5] = 6; // option length
1778 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1779 config->bind_address ? config->bind_address :
1780 my_address; // send my IP
1781
1782 tunnelsend(buf, 10 + (q - buf), t); // send it
1783 restart_timer(s, ipcp);
1784 }
1785
1786 void sendipv6cp(sessionidt s, tunnelidt t)
1787 {
1788 uint8_t buf[MAXETHER];
1789 uint8_t *q;
1790
1791 CSTAT(sendipv6cp);
1792 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1793
1794 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP, 0, 0, 0);
1795 if (!q) return;
1796
1797 *q = ConfigReq;
1798 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1799 // only send one type
1800 // of request
1801 *(uint16_t *) (q + 2) = htons(14);
1802 q[4] = 1; // interface identifier option
1803 q[5] = 10; // option length
1804 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1805 *(uint32_t *) (q + 10) = 0;
1806 q[13] = 1;
1807
1808 tunnelsend(buf, 14 + (q - buf), t); // send it
1809 restart_timer(s, ipv6cp);
1810 }
1811
1812 static void sessionclear(sessionidt s)
1813 {
1814 memset(&session[s], 0, sizeof(session[s]));
1815 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1816 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1817
1818 session[s].tunnel = T_FREE; // Mark it as free.
1819 session[s].next = sessionfree;
1820 sessionfree = s;
1821 }
1822
1823 // kill a session now
1824 void sessionkill(sessionidt s, char *reason)
1825 {
1826 bundleidt b;
1827
1828 CSTAT(sessionkill);
1829
1830 if (!session[s].opened) // not alive
1831 return;
1832
1833 if (session[s].next)
1834 {
1835 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%u)\n", session[s].next);
1836 return;
1837 }
1838
1839 session[s].die = TIME;
1840 sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
1841 if (sess_local[s].radius)
1842 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1843
1844 LOG(2, s, session[s].tunnel, "Kill session %u (%s): %s\n", s, session[s].user, reason);
1845 if ((b = session[s].bundle))
1846 {
1847 // This session was part of a bundle
1848 bundle[b].num_of_links--;
1849 LOG(3, s, 0, "MPPP: Dropping member link: %u from bundle %u\n", s, b);
1850 if (bundle[b].num_of_links == 0)
1851 {
1852 bundleclear(b);
1853 LOG(3, s, 0, "MPPP: Kill bundle: %u (No remaing member links)\n", b);
1854 }
1855 else
1856 {
1857 // Adjust the members array to accomodate the new change
1858 uint8_t mem_num = 0;
1859 // It should be here num_of_links instead of num_of_links-1 (previous instruction "num_of_links--")
1860 if (bundle[b].members[bundle[b].num_of_links] != s)
1861 {
1862 uint8_t ml;
1863 for (ml = 0; ml<bundle[b].num_of_links; ml++)
1864 {
1865 if (bundle[b].members[ml] == s)
1866 {
1867 mem_num = ml;
1868 break;
1869 }
1870 }
1871 bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
1872 LOG(3, s, 0, "MPPP: Adjusted member links array\n");
1873 }
1874 }
1875 cluster_send_bundle(b);
1876 }
1877 sessionclear(s);
1878 cluster_send_session(s);
1879 }
1880
1881 static void tunnelclear(tunnelidt t)
1882 {
1883 if (!t) return;
1884 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1885 tunnel[t].state = TUNNELFREE;
1886 }
1887
1888 static void bundleclear(bundleidt b)
1889 {
1890 if (!b) return;
1891 memset(&bundle[b], 0, sizeof(bundle[b]));
1892 bundle[b].state = BUNDLEFREE;
1893 }
1894
1895 // kill a tunnel now
1896 static void tunnelkill(tunnelidt t, char *reason)
1897 {
1898 sessionidt s;
1899 controlt *c;
1900
1901 CSTAT(tunnelkill);
1902
1903 tunnel[t].state = TUNNELDIE;
1904
1905 // free control messages
1906 while ((c = tunnel[t].controls))
1907 {
1908 controlt * n = c->next;
1909 tunnel[t].controls = n;
1910 tunnel[t].controlc--;
1911 c->next = controlfree;
1912 controlfree = c;
1913 }
1914 // kill sessions
1915 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1916 if (session[s].tunnel == t)
1917 sessionkill(s, reason);
1918
1919 // free tunnel
1920 tunnelclear(t);
1921 LOG(1, 0, t, "Kill tunnel %u: %s\n", t, reason);
1922 cli_tunnel_actions[t].action = 0;
1923 cluster_send_tunnel(t);
1924 }
1925
1926 // shut down a tunnel cleanly
1927 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1928 {
1929 sessionidt s;
1930
1931 CSTAT(tunnelshutdown);
1932
1933 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1934 {
1935 // never set up, can immediately kill
1936 tunnelkill(t, reason);
1937 return;
1938 }
1939 LOG(1, 0, t, "Shutting down tunnel %u (%s)\n", t, reason);
1940
1941 // close session
1942 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1943 if (session[s].tunnel == t)
1944 sessionshutdown(s, reason, CDN_NONE, TERM_ADMIN_RESET);
1945
1946 tunnel[t].state = TUNNELDIE;
1947 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1948 cluster_send_tunnel(t);
1949 // TBA - should we wait for sessions to stop?
1950 if (result)
1951 {
1952 controlt *c = controlnew(4); // sending StopCCN
1953 if (error)
1954 {
1955 uint8_t buf[64];
1956 int l = 4;
1957 *(uint16_t *) buf = htons(result);
1958 *(uint16_t *) (buf+2) = htons(error);
1959 if (msg)
1960 {
1961 int m = strlen(msg);
1962 if (m + 4 > sizeof(buf))
1963 m = sizeof(buf) - 4;
1964
1965 memcpy(buf+4, msg, m);
1966 l += m;
1967 }
1968
1969 controlb(c, 1, buf, l, 1);
1970 }
1971 else
1972 control16(c, 1, result, 1);
1973
1974 control16(c, 9, t, 1); // assigned tunnel (our end)
1975 controladd(c, 0, t); // send the message
1976 }
1977 }
1978
1979 // read and process packet on tunnel (UDP)
1980 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1981 {
1982 uint8_t *chapresponse = NULL;
1983 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1984 uint8_t *p = buf + 2;
1985
1986
1987 CSTAT(processudp);
1988
1989 udp_rx += len;
1990 udp_rx_pkt++;
1991 LOG_HEX(5, "UDP Data", buf, len);
1992 STAT(tunnel_rx_packets);
1993 INC_STAT(tunnel_rx_bytes, len);
1994 if (len < 6)
1995 {
1996 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1997 STAT(tunnel_rx_errors);
1998 return;
1999 }
2000 if ((buf[1] & 0x0F) != 2)
2001 {
2002 LOG(1, 0, 0, "Bad L2TP ver %d\n", buf[1] & 0x0F);
2003 STAT(tunnel_rx_errors);
2004 return;
2005 }
2006 if (*buf & 0x40)
2007 { // length
2008 l = ntohs(*(uint16_t *) p);
2009 p += 2;
2010 }
2011 t = ntohs(*(uint16_t *) p);
2012 p += 2;
2013 s = ntohs(*(uint16_t *) p);
2014 p += 2;
2015 if (s >= MAXSESSION)
2016 {
2017 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
2018 STAT(tunnel_rx_errors);
2019 return;
2020 }
2021 if (t >= MAXTUNNEL)
2022 {
2023 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
2024 STAT(tunnel_rx_errors);
2025 return;
2026 }
2027 if (*buf & 0x08)
2028 { // ns/nr
2029 ns = ntohs(*(uint16_t *) p);
2030 p += 2;
2031 nr = ntohs(*(uint16_t *) p);
2032 p += 2;
2033 }
2034 if (*buf & 0x02)
2035 { // offset
2036 uint16_t o = ntohs(*(uint16_t *) p);
2037 p += o + 2;
2038 }
2039 if ((p - buf) > l)
2040 {
2041 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
2042 STAT(tunnel_rx_errors);
2043 return;
2044 }
2045 l -= (p - buf);
2046
2047 // used to time out old tunnels
2048 if (t && tunnel[t].state == TUNNELOPEN)
2049 tunnel[t].lastrec = time_now;
2050
2051 if (*buf & 0x80)
2052 { // control
2053 uint16_t message = 0xFFFF; // message type
2054 uint8_t fatal = 0;
2055 uint8_t mandatory = 0;
2056 uint16_t asession = 0; // assigned session
2057 uint32_t amagic = 0; // magic number
2058 uint8_t aflags = 0; // flags from last LCF
2059 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
2060 char called[MAXTEL] = ""; // called number
2061 char calling[MAXTEL] = ""; // calling number
2062
2063 if (!config->cluster_iam_master)
2064 {
2065 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2066 return;
2067 }
2068
2069 // control messages must have bits 0x80|0x40|0x08
2070 // (type, length and sequence) set, and bits 0x02|0x01
2071 // (offset and priority) clear
2072 if ((*buf & 0xCB) != 0xC8)
2073 {
2074 LOG(1, s, t, "Bad control header %02X\n", *buf);
2075 STAT(tunnel_rx_errors);
2076 return;
2077 }
2078
2079 // check for duplicate tunnel open message
2080 if (!t && ns == 0)
2081 {
2082 int i;
2083
2084 //
2085 // Is this a duplicate of the first packet? (SCCRQ)
2086 //
2087 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
2088 {
2089 if (tunnel[i].state != TUNNELOPENING ||
2090 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
2091 tunnel[i].port != ntohs(addr->sin_port) )
2092 continue;
2093 t = i;
2094 LOG(3, s, t, "Duplicate SCCRQ?\n");
2095 break;
2096 }
2097 }
2098
2099 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %u l-nr %u r-ns %u r-nr %u\n",
2100 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
2101
2102 // if no tunnel specified, assign one
2103 if (!t)
2104 {
2105 if (!(t = new_tunnel()))
2106 {
2107 LOG(1, 0, 0, "No more tunnels\n");
2108 STAT(tunnel_overflow);
2109 return;
2110 }
2111 tunnelclear(t);
2112 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
2113 tunnel[t].port = ntohs(addr->sin_port);
2114 tunnel[t].window = 4; // default window
2115 STAT(tunnel_created);
2116 LOG(1, 0, t, " New tunnel from %s:%u ID %u\n",
2117 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
2118 }
2119
2120 // If the 'ns' just received is not the 'nr' we're
2121 // expecting, just send an ack and drop it.
2122 //
2123 // if 'ns' is less, then we got a retransmitted packet.
2124 // if 'ns' is greater than missed a packet. Either way
2125 // we should ignore it.
2126 if (ns != tunnel[t].nr)
2127 {
2128 // is this the sequence we were expecting?
2129 STAT(tunnel_rx_errors);
2130 LOG(1, 0, t, " Out of sequence tunnel %u, (%u is not the expected %u)\n",
2131 t, ns, tunnel[t].nr);
2132
2133 if (l) // Is this not a ZLB?
2134 controlnull(t);
2135 return;
2136 }
2137
2138 // check sequence of this message
2139 {
2140 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2141 // some to clear maybe?
2142 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2143 {
2144 controlt *c = tunnel[t].controls;
2145 tunnel[t].controls = c->next;
2146 tunnel[t].controlc--;
2147 c->next = controlfree;
2148 controlfree = c;
2149 skip--;
2150 tunnel[t].try = 0; // we have progress
2151 }
2152
2153 // receiver advance (do here so quoted correctly in any sends below)
2154 if (l) tunnel[t].nr = (ns + 1);
2155 if (skip < 0) skip = 0;
2156 if (skip < tunnel[t].controlc)
2157 {
2158 // some control packets can now be sent that were previous stuck out of window
2159 int tosend = tunnel[t].window - skip;
2160 controlt *c = tunnel[t].controls;
2161 while (c && skip)
2162 {
2163 c = c->next;
2164 skip--;
2165 }
2166 while (c && tosend)
2167 {
2168 tunnel[t].try = 0; // first send
2169 tunnelsend(c->buf, c->length, t);
2170 c = c->next;
2171 tosend--;
2172 }
2173 }
2174 if (!tunnel[t].controlc)
2175 tunnel[t].retry = 0; // caught up
2176 }
2177 if (l)
2178 { // if not a null message
2179 int result = 0;
2180 int error = 0;
2181 char *msg = 0;
2182
2183 // default disconnect cause/message on receipt
2184 // of CDN (set to more specific value from
2185 // attribute 46 if present below).
2186 int disc_cause = TERM_NAS_REQUEST;
2187 char const *disc_reason = "Closed (Received CDN).";
2188
2189 // process AVPs
2190 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2191 {
2192 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2193 uint8_t *b = p;
2194 uint8_t flags = *p;
2195 uint16_t mtype;
2196
2197 if (n > l)
2198 {
2199 LOG(1, s, t, "Invalid length in AVP\n");
2200 STAT(tunnel_rx_errors);
2201 return;
2202 }
2203 p += n; // next
2204 l -= n;
2205 if (flags & 0x3C) // reserved bits, should be clear
2206 {
2207 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2208 fatal = flags;
2209 result = 2; // general error
2210 error = 3; // reserved field non-zero
2211 msg = 0;
2212 continue; // next
2213 }
2214 b += 2;
2215 if (*(uint16_t *) (b))
2216 {
2217 LOG(2, s, t, "Unknown AVP vendor %u\n", ntohs(*(uint16_t *) (b)));
2218 fatal = flags;
2219 result = 2; // general error
2220 error = 6; // generic vendor-specific error
2221 msg = "unsupported vendor-specific";
2222 continue; // next
2223 }
2224 b += 2;
2225 mtype = ntohs(*(uint16_t *) (b));
2226 b += 2;
2227 n -= 6;
2228
2229 if (flags & 0x40)
2230 {
2231 uint16_t orig_len;
2232
2233 // handle hidden AVPs
2234 if (!*config->l2tp_secret)
2235 {
2236 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2237 fatal = flags;
2238 result = 2; // general error
2239 error = 6; // generic vendor-specific error
2240 msg = "secret not specified";
2241 continue;
2242 }
2243 if (!session[s].random_vector_length)
2244 {
2245 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2246 fatal = flags;
2247 result = 2; // general error
2248 error = 6; // generic
2249 msg = "no random vector";
2250 continue;
2251 }
2252 if (n < 8)
2253 {
2254 LOG(2, s, t, "Short hidden AVP.\n");
2255 fatal = flags;
2256 result = 2; // general error
2257 error = 2; // length is wrong
2258 msg = 0;
2259 continue;
2260 }
2261
2262 // Unhide the AVP
2263 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2264
2265 orig_len = ntohs(*(uint16_t *) b);
2266 if (orig_len > n + 2)
2267 {
2268 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2269 orig_len, n);
2270
2271 fatal = flags;
2272 result = 2; // general error
2273 error = 2; // length is wrong
2274 msg = 0;
2275 continue;
2276 }
2277
2278 b += 2;
2279 n = orig_len;
2280 }
2281
2282 LOG(4, s, t, " AVP %u (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2283 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2284
2285 switch (mtype)
2286 {
2287 case 0: // message type
2288 message = ntohs(*(uint16_t *) b);
2289 mandatory = flags & 0x80;
2290 LOG(4, s, t, " Message type = %u (%s)\n", *b, l2tp_code(message));
2291 break;
2292 case 1: // result code
2293 {
2294 uint16_t rescode = ntohs(*(uint16_t *) b);
2295 const char* resdesc = "(unknown)";
2296 if (message == 4)
2297 { /* StopCCN */
2298 resdesc = l2tp_stopccn_result_code(rescode);
2299 }
2300 else if (message == 14)
2301 { /* CDN */
2302 resdesc = l2tp_cdn_result_code(rescode);
2303 }
2304
2305 LOG(4, s, t, " Result Code %u: %s\n", rescode, resdesc);
2306 if (n >= 4)
2307 {
2308 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2309 LOG(4, s, t, " Error Code %u: %s\n", errcode, l2tp_error_code(errcode));
2310 }
2311 if (n > 4)
2312 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2313
2314 break;
2315 }
2316 break;
2317 case 2: // protocol version
2318 {
2319 version = ntohs(*(uint16_t *) (b));
2320 LOG(4, s, t, " Protocol version = %u\n", version);
2321 if (version && version != 0x0100)
2322 { // allow 0.0 and 1.0
2323 LOG(1, s, t, " Bad protocol version %04X\n", version);
2324 fatal = flags;
2325 result = 5; // unspported protocol version
2326 error = 0x0100; // supported version
2327 msg = 0;
2328 continue; // next
2329 }
2330 }
2331 break;
2332 case 3: // framing capabilities
2333 break;
2334 case 4: // bearer capabilities
2335 break;
2336 case 5: // tie breaker
2337 // We never open tunnels, so we don't care about tie breakers
2338 continue;
2339 case 6: // firmware revision
2340 break;
2341 case 7: // host name
2342 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2343 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2344 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2345 // TBA - to send to RADIUS
2346 break;
2347 case 8: // vendor name
2348 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2349 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2350 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2351 break;
2352 case 9: // assigned tunnel
2353 tunnel[t].far = ntohs(*(uint16_t *) (b));
2354 LOG(4, s, t, " Remote tunnel id = %u\n", tunnel[t].far);
2355 break;
2356 case 10: // rx window
2357 tunnel[t].window = ntohs(*(uint16_t *) (b));
2358 if (!tunnel[t].window)
2359 tunnel[t].window = 1; // window of 0 is silly
2360 LOG(4, s, t, " rx window = %u\n", tunnel[t].window);
2361 break;
2362 case 11: // Challenge
2363 {
2364 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2365 build_chap_response(b, 2, n, &chapresponse);
2366 }
2367 break;
2368 case 13: // Response
2369 // Why did they send a response? We never challenge.
2370 LOG(2, s, t, " received unexpected challenge response\n");
2371 break;
2372
2373 case 14: // assigned session
2374 asession = session[s].far = ntohs(*(uint16_t *) (b));
2375 LOG(4, s, t, " assigned session = %u\n", asession);
2376 break;
2377 case 15: // call serial number
2378 LOG(4, s, t, " call serial number = %u\n", ntohl(*(uint32_t *)b));
2379 break;
2380 case 18: // bearer type
2381 LOG(4, s, t, " bearer type = %u\n", ntohl(*(uint32_t *)b));
2382 // TBA - for RADIUS
2383 break;
2384 case 19: // framing type
2385 LOG(4, s, t, " framing type = %u\n", ntohl(*(uint32_t *)b));
2386 // TBA
2387 break;
2388 case 21: // called number
2389 memset(called, 0, sizeof(called));
2390 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2391 LOG(4, s, t, " Called <%s>\n", called);
2392 break;
2393 case 22: // calling number
2394 memset(calling, 0, sizeof(calling));
2395 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2396 LOG(4, s, t, " Calling <%s>\n", calling);
2397 break;
2398 case 23: // subtype
2399 break;
2400 case 24: // tx connect speed
2401 if (n == 4)
2402 {
2403 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2404 }
2405 else
2406 {
2407 // AS5300s send connect speed as a string
2408 char tmp[30];
2409 memset(tmp, 0, sizeof(tmp));
2410 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2411 session[s].tx_connect_speed = atol(tmp);
2412 }
2413 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2414 break;
2415 case 38: // rx connect speed
2416 if (n == 4)
2417 {
2418 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2419 }
2420 else
2421 {
2422 // AS5300s send connect speed as a string
2423 char tmp[30];
2424 memset(tmp, 0, sizeof(tmp));
2425 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2426 session[s].rx_connect_speed = atol(tmp);
2427 }
2428 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2429 break;
2430 case 25: // Physical Channel ID
2431 {
2432 uint32_t tmp = ntohl(*(uint32_t *) b);
2433 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2434 break;
2435 }
2436 case 29: // Proxy Authentication Type
2437 {
2438 uint16_t atype = ntohs(*(uint16_t *)b);
2439 LOG(4, s, t, " Proxy Auth Type %u (%s)\n", atype, ppp_auth_type(atype));
2440 break;
2441 }
2442 case 30: // Proxy Authentication Name
2443 {
2444 char authname[64];
2445 memset(authname, 0, sizeof(authname));
2446 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2447 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2448 authname);
2449 break;
2450 }
2451 case 31: // Proxy Authentication Challenge
2452 {
2453 LOG(4, s, t, " Proxy Auth Challenge\n");
2454 break;
2455 }
2456 case 32: // Proxy Authentication ID
2457 {
2458 uint16_t authid = ntohs(*(uint16_t *)(b));
2459 LOG(4, s, t, " Proxy Auth ID (%u)\n", authid);
2460 break;
2461 }
2462 case 33: // Proxy Authentication Response
2463 LOG(4, s, t, " Proxy Auth Response\n");
2464 break;
2465 case 27: // last sent lcp
2466 { // find magic number
2467 uint8_t *p = b, *e = p + n;
2468 while (p + 1 < e && p[1] && p + p[1] <= e)
2469 {
2470 if (*p == 5 && p[1] == 6) // Magic-Number
2471 amagic = ntohl(*(uint32_t *) (p + 2));
2472 else if (*p == 7) // Protocol-Field-Compression
2473 aflags |= SESSION_PFC;
2474 else if (*p == 8) // Address-and-Control-Field-Compression
2475 aflags |= SESSION_ACFC;
2476 p += p[1];
2477 }
2478 }
2479 break;
2480 case 28: // last recv lcp confreq
2481 break;
2482 case 26: // Initial Received LCP CONFREQ
2483 break;
2484 case 39: // seq required - we control it as an LNS anyway...
2485 break;
2486 case 36: // Random Vector
2487 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2488 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2489 if (n > sizeof(session[s].random_vector))
2490 n = sizeof(session[s].random_vector);
2491 memcpy(session[s].random_vector, b, n);
2492 session[s].random_vector_length = n;
2493 break;
2494 case 46: // ppp disconnect cause
2495 if (n >= 5)
2496 {
2497 uint16_t code = ntohs(*(uint16_t *) b);
2498 uint16_t proto = ntohs(*(uint16_t *) (b + 2));
2499 uint8_t dir = *(b + 4);
2500
2501 LOG(4, s, t, " PPP disconnect cause "
2502 "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
2503 code, proto, dir, n - 5, b + 5);
2504
2505 switch (code)
2506 {
2507 case 1: // admin disconnect
2508 disc_cause = TERM_ADMIN_RESET;
2509 disc_reason = "Administrative disconnect";
2510 break;
2511 case 3: // lcp terminate
2512 if (dir != 2) break; // 1=peer (LNS), 2=local (LAC)
2513 disc_cause = TERM_USER_REQUEST;
2514 disc_reason = "Normal disconnection";
2515 break;
2516 case 4: // compulsory encryption unavailable
2517 if (dir != 1) break; // 1=refused by peer, 2=local
2518 disc_cause = TERM_USER_ERROR;
2519 disc_reason = "Compulsory encryption refused";
2520 break;
2521 case 5: // lcp: fsm timeout
2522 disc_cause = TERM_PORT_ERROR;
2523 disc_reason = "LCP: FSM timeout";
2524 break;
2525 case 6: // lcp: no recognisable lcp packets received
2526 disc_cause = TERM_PORT_ERROR;
2527 disc_reason = "LCP: no recognisable LCP packets";
2528 break;
2529 case 7: // lcp: magic-no error (possibly looped back)
2530 disc_cause = TERM_PORT_ERROR;
2531 disc_reason = "LCP: magic-no error (possible loop)";
2532 break;
2533 case 8: // lcp: echo request timeout
2534 disc_cause = TERM_PORT_ERROR;
2535 disc_reason = "LCP: echo request timeout";
2536 break;
2537 case 13: // auth: fsm timeout
2538 disc_cause = TERM_SERVICE_UNAVAILABLE;
2539 disc_reason = "Authentication: FSM timeout";
2540 break;
2541 case 15: // auth: unacceptable auth protocol
2542 disc_cause = TERM_SERVICE_UNAVAILABLE;
2543 disc_reason = "Unacceptable authentication protocol";
2544 break;
2545 case 16: // auth: authentication failed
2546 disc_cause = TERM_SERVICE_UNAVAILABLE;
2547 disc_reason = "Authentication failed";
2548 break;
2549 case 17: // ncp: fsm timeout
2550 disc_cause = TERM_SERVICE_UNAVAILABLE;
2551 disc_reason = "NCP: FSM timeout";
2552 break;
2553 case 18: // ncp: no ncps available
2554 disc_cause = TERM_SERVICE_UNAVAILABLE;
2555 disc_reason = "NCP: no NCPs available";
2556 break;
2557 case 19: // ncp: failure to converge on acceptable address
2558 disc_cause = TERM_SERVICE_UNAVAILABLE;
2559 disc_reason = (dir == 1)
2560 ? "NCP: too many Configure-Naks received from peer"
2561 : "NCP: too many Configure-Naks sent to peer";
2562 break;
2563 case 20: // ncp: user not permitted to use any address
2564 disc_cause = TERM_SERVICE_UNAVAILABLE;
2565 disc_reason = (dir == 1)
2566 ? "NCP: local link address not acceptable to peer"
2567 : "NCP: remote link address not acceptable";
2568 break;
2569 }
2570 }
2571 break;
2572 default:
2573 {
2574 static char e[] = "unknown AVP 0xXXXX";
2575 LOG(2, s, t, " Unknown AVP type %u\n", mtype);
2576 fatal = flags;
2577 result = 2; // general error
2578 error = 8; // unknown mandatory AVP
2579 sprintf((msg = e) + 14, "%04x", mtype);
2580 continue; // next
2581 }
2582 }
2583 }
2584 // process message
2585 if (fatal & 0x80)
2586 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2587 else
2588 switch (message)
2589 {
2590 case 1: // SCCRQ - Start Control Connection Request
2591 tunnel[t].state = TUNNELOPENING;
2592 if (main_quit != QUIT_SHUTDOWN)
2593 {
2594 controlt *c = controlnew(2); // sending SCCRP
2595 control16(c, 2, version, 1); // protocol version
2596 control32(c, 3, 3, 1); // framing
2597 controls(c, 7, hostname, 1); // host name
2598 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2599 control16(c, 9, t, 1); // assigned tunnel
2600 controladd(c, 0, t); // send the resply
2601 }
2602 else
2603 {
2604 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2605 }
2606 break;
2607 case 2: // SCCRP
2608 tunnel[t].state = TUNNELOPEN;
2609 break;
2610 case 3: // SCCN
2611 tunnel[t].state = TUNNELOPEN;
2612 controlnull(t); // ack
2613 break;
2614 case 4: // StopCCN
2615 controlnull(t); // ack
2616 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2617 break;
2618 case 6: // HELLO
2619 controlnull(t); // simply ACK
2620 break;
2621 case 7: // OCRQ
2622 // TBA
2623 break;
2624 case 8: // OCRO
2625 // TBA
2626 break;
2627 case 9: // OCCN
2628 // TBA
2629 break;
2630 case 10: // ICRQ
2631 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2632 {
2633 controlt *c = controlnew(11); // ICRP
2634
2635 s = sessionfree;
2636 sessionfree = session[s].next;
2637 memset(&session[s], 0, sizeof(session[s]));
2638
2639 if (s > config->cluster_highest_sessionid)
2640 config->cluster_highest_sessionid = s;
2641
2642 session[s].opened = time_now;
2643 session[s].tunnel = t;
2644 session[s].far = asession;
2645 session[s].last_packet = time_now;
2646 LOG(3, s, t, "New session (%u/%u)\n", tunnel[t].far, session[s].far);
2647 control16(c, 14, s, 1); // assigned session
2648 controladd(c, asession, t); // send the reply
2649
2650 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2651 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2652
2653 session[s].ppp.phase = Establish;
2654 session[s].ppp.lcp = Starting;
2655
2656 STAT(session_created);
2657 break;
2658 }
2659
2660 {
2661 controlt *c = controlnew(14); // CDN
2662 if (!sessionfree)
2663 {
2664 STAT(session_overflow);
2665 LOG(1, 0, t, "No free sessions\n");
2666 control16(c, 1, 4, 0); // temporary lack of resources
2667 }
2668 else
2669 control16(c, 1, 2, 7); // shutting down, try another
2670
2671 controladd(c, asession, t); // send the message
2672 }
2673 return;
2674 case 11: // ICRP
2675 // TBA
2676 break;
2677 case 12: // ICCN
2678 if (amagic == 0) amagic = time_now;
2679 session[s].magic = amagic; // set magic number
2680 session[s].flags = aflags; // set flags received
2681 session[s].mru = PPPoE_MRU; // default
2682 controlnull(t); // ack
2683
2684 // start LCP
2685 sess_local[s].lcp_authtype = config->radius_authprefer;
2686 sess_local[s].ppp_mru = MRU;
2687
2688 // Set multilink options before sending initial LCP packet
2689 sess_local[s].mp_mrru = 1614;
2690 sess_local[s].mp_epdis = config->bind_address ? config->bind_address : my_address;
2691
2692 sendlcp(s, t);
2693 change_state(s, lcp, RequestSent);
2694 break;
2695
2696 case 14: // CDN
2697 controlnull(t); // ack
2698 sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
2699 break;
2700 case 0xFFFF:
2701 LOG(1, s, t, "Missing message type\n");
2702 break;
2703 default:
2704 STAT(tunnel_rx_errors);
2705 if (mandatory)
2706 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2707 else
2708 LOG(1, s, t, "Unknown message type %u\n", message);
2709 break;
2710 }
2711 if (chapresponse) free(chapresponse);
2712 cluster_send_tunnel(t);
2713 }
2714 else
2715 {
2716 LOG(4, s, t, " Got a ZLB ack\n");
2717 }
2718 }
2719 else
2720 { // data
2721 uint16_t proto;
2722
2723 LOG_HEX(5, "Receive Tunnel Data", p, l);
2724 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2725 { // HDLC address header, discard
2726 p += 2;
2727 l -= 2;
2728 }
2729 if (l < 2)
2730 {
2731 LOG(1, s, t, "Short ppp length %d\n", l);
2732 STAT(tunnel_rx_errors);
2733 return;
2734 }
2735 if (*p & 1)
2736 {
2737 proto = *p++;
2738 l--;
2739 }
2740 else
2741 {
2742 proto = ntohs(*(uint16_t *) p);
2743 p += 2;
2744 l -= 2;
2745 }
2746
2747 if (s && !session[s].opened) // Is something wrong??
2748 {
2749 if (!config->cluster_iam_master)
2750 {
2751 // Pass it off to the master to deal with..
2752 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2753 return;
2754 }
2755
2756
2757 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2758 STAT(tunnel_rx_errors);
2759 return;
2760 }
2761
2762 if (proto == PPPPAP)
2763 {
2764 session[s].last_packet = time_now;
2765 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2766 processpap(s, t, p, l);
2767 }
2768 else if (proto == PPPCHAP)
2769 {
2770 session[s].last_packet = time_now;
2771 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2772 processchap(s, t, p, l);
2773 }
2774 else if (proto == PPPLCP)
2775 {
2776 session[s].last_packet = time_now;
2777 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2778 processlcp(s, t, p, l);
2779 }
2780 else if (proto == PPPIPCP)
2781 {
2782 session[s].last_packet = time_now;
2783 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2784 processipcp(s, t, p, l);
2785 }
2786 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2787 {
2788 session[s].last_packet = time_now;
2789 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2790 processipv6cp(s, t, p, l);
2791 }
2792 else if (proto == PPPCCP)
2793 {
2794 session[s].last_packet = time_now;
2795 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2796 processccp(s, t, p, l);
2797 }
2798 else if (proto == PPPIP)
2799 {
2800 if (session[s].die)
2801 {
2802 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2803 return; // closing session, PPP not processed
2804 }
2805
2806 session[s].last_packet = time_now;
2807 if (session[s].walled_garden && !config->cluster_iam_master)
2808 {
2809 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2810 return;
2811 }
2812
2813 processipin(s, t, p, l);
2814 }
2815 else if (proto == PPPMP)
2816 {
2817 if (session[s].die)
2818 {
2819 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2820 return; // closing session, PPP not processed
2821 }
2822
2823 session[s].last_packet = time_now;
2824 if (session[s].walled_garden && !config->cluster_iam_master)
2825 {
2826 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2827 return;
2828 }
2829
2830 processmpin(s, t, p, l);
2831 }
2832 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2833 {
2834 if (session[s].die)
2835 {
2836 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2837 return; // closing session, PPP not processed
2838 }
2839
2840 session[s].last_packet = time_now;
2841 if (session[s].walled_garden && !config->cluster_iam_master)
2842 {
2843 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2844 return;
2845 }
2846
2847 processipv6in(s, t, p, l);
2848 }
2849 else if (session[s].ppp.lcp == Opened)
2850 {
2851 session[s].last_packet = time_now;
2852 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2853 protoreject(s, t, p, l, proto);
2854 }
2855 else
2856 {
2857 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2858 proto, ppp_state(session[s].ppp.lcp));
2859 }
2860 }
2861 }
2862
2863 // read and process packet on tun
2864 static void processtun(uint8_t * buf, int len)
2865 {
2866 LOG_HEX(5, "Receive TUN Data", buf, len);
2867 STAT(tun_rx_packets);
2868 INC_STAT(tun_rx_bytes, len);
2869
2870 CSTAT(processtun);
2871
2872 eth_rx_pkt++;
2873 eth_rx += len;
2874 if (len < 22)
2875 {
2876 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2877 STAT(tun_rx_errors);
2878 return;
2879 }
2880
2881 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2882 processipout(buf, len);
2883 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2884 && config->ipv6_prefix.s6_addr[0])
2885 processipv6out(buf, len);
2886
2887 // Else discard.
2888 }
2889
2890 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2891 // that we look at the whole of the tunnel, radius and session tables
2892 // every second
2893 static void regular_cleanups(double period)
2894 {
2895 // Next tunnel, radius and session to check for actions on.
2896 static tunnelidt t = 0;
2897 static int r = 0;
2898 static sessionidt s = 0;
2899
2900 int t_actions = 0;
2901 int r_actions = 0;
2902 int s_actions = 0;
2903
2904 int t_slice;
2905 int r_slice;
2906 int s_slice;
2907
2908 int i;
2909 int a;
2910
2911 // divide up tables into slices based on the last run
2912 t_slice = config->cluster_highest_tunnelid * period;
2913 r_slice = (MAXRADIUS - 1) * period;
2914 s_slice = config->cluster_highest_sessionid * period;
2915
2916 if (t_slice < 1)
2917 t_slice = 1;
2918 else if (t_slice > config->cluster_highest_tunnelid)
2919 t_slice = config->cluster_highest_tunnelid;
2920
2921 if (r_slice < 1)
2922 r_slice = 1;
2923 else if (r_slice > (MAXRADIUS - 1))
2924 r_slice = MAXRADIUS - 1;
2925
2926 if (s_slice < 1)
2927 s_slice = 1;
2928 else if (s_slice > config->cluster_highest_sessionid)
2929 s_slice = config->cluster_highest_sessionid;
2930
2931 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2932
2933 for (i = 0; i < t_slice; i++)
2934 {
2935 t++;
2936 if (t > config->cluster_highest_tunnelid)
2937 t = 1;
2938
2939 // check for expired tunnels
2940 if (tunnel[t].die && tunnel[t].die <= TIME)
2941 {
2942 STAT(tunnel_timeout);
2943 tunnelkill(t, "Expired");
2944 t_actions++;
2945 continue;
2946 }
2947 // check for message resend
2948 if (tunnel[t].retry && tunnel[t].controlc)
2949 {
2950 // resend pending messages as timeout on reply
2951 if (tunnel[t].retry <= TIME)
2952 {
2953 controlt *c = tunnel[t].controls;
2954 uint8_t w = tunnel[t].window;
2955 tunnel[t].try++; // another try
2956 if (tunnel[t].try > 5)
2957 tunnelkill(t, "Timeout on control message"); // game over
2958 else
2959 while (c && w--)
2960 {
2961 tunnelsend(c->buf, c->length, t);
2962 c = c->next;
2963 }
2964
2965 t_actions++;
2966 }
2967 }
2968 // Send hello
2969 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
2970 {
2971 controlt *c = controlnew(6); // sending HELLO
2972 controladd(c, 0, t); // send the message
2973 LOG(3, 0, t, "Sending HELLO message\n");
2974 t_actions++;
2975 }
2976
2977 // Check for tunnel changes requested from the CLI
2978 if ((a = cli_tunnel_actions[t].action))
2979 {
2980 cli_tunnel_actions[t].action = 0;
2981 if (a & CLI_TUN_KILL)
2982 {
2983 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2984 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2985 t_actions++;
2986 }
2987 }
2988 }
2989
2990 for (i = 0; i < r_slice; i++)
2991 {
2992 r++;
2993 if (r >= MAXRADIUS)
2994 r = 1;
2995
2996 if (!radius[r].state)
2997 continue;
2998
2999 if (radius[r].retry <= TIME)
3000 {
3001 radiusretry(r);
3002 r_actions++;
3003 }
3004 }
3005
3006 for (i = 0; i < s_slice; i++)
3007 {
3008 s++;
3009 if (s > config->cluster_highest_sessionid)
3010 s = 1;
3011
3012 if (!session[s].opened) // Session isn't in use
3013 continue;
3014
3015 // check for expired sessions
3016 if (session[s].die)
3017 {
3018 if (session[s].die <= TIME)
3019 {
3020 sessionkill(s, "Expired");
3021 s_actions++;
3022 }
3023 continue;
3024 }
3025
3026 // check for timed out sessions
3027 if (session[s].timeout)
3028 {
3029 bundleidt bid = session[s].bundle;
3030 if (bid)
3031 {
3032 clockt curr_time = time_now;
3033 if (curr_time - bundle[bid].last_check >= 1)
3034 {
3035 bundle[bid].online_time += (curr_time-bundle[bid].last_check)*bundle[bid].num_of_links;
3036 bundle[bid].last_check = curr_time;
3037 if (bundle[bid].online_time >= session[s].timeout)
3038 {
3039 int ses;
3040 for (ses = bundle[bid].num_of_links - 1; ses >= 0; ses--)
3041 {
3042 sessionshutdown(bundle[bid].members[ses], "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3043 s_actions++;
3044 continue;
3045 }
3046 }
3047 }
3048 }
3049 else if (session[s].timeout <= time_now - session[s].opened)
3050 {
3051 sessionshutdown(s, "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3052 s_actions++;
3053 continue;
3054 }
3055 }
3056
3057 // PPP timeouts
3058 if (sess_local[s].lcp.restart <= time_now)
3059 {
3060 int next_state = session[s].ppp.lcp;
3061 switch (session[s].ppp.lcp)
3062 {
3063 case RequestSent:
3064 case AckReceived:
3065 next_state = RequestSent;
3066
3067 case AckSent:
3068 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
3069 {
3070 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
3071 sendlcp(s, session[s].tunnel);
3072 change_state(s, lcp, next_state);
3073 }
3074 else
3075 {
3076 sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3077 STAT(session_timeout);
3078 }
3079
3080 s_actions++;
3081 }
3082
3083 if (session[s].die)
3084 continue;
3085 }
3086
3087 if (sess_local[s].ipcp.restart <= time_now)
3088 {
3089 int next_state = session[s].ppp.ipcp;
3090 switch (session[s].ppp.ipcp)
3091 {
3092 case RequestSent:
3093 case AckReceived:
3094 next_state = RequestSent;
3095
3096 case AckSent:
3097 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
3098 {
3099 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
3100 sendipcp(s, session[s].tunnel);
3101 change_state(s, ipcp, next_state);
3102 }
3103 else
3104 {
3105 sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3106 STAT(session_timeout);
3107 }
3108
3109 s_actions++;
3110 }
3111
3112 if (session[s].die)
3113 continue;
3114 }
3115
3116 if (sess_local[s].ipv6cp.restart <= time_now)
3117 {
3118 int next_state = session[s].ppp.ipv6cp;
3119 switch (session[s].ppp.ipv6cp)
3120 {
3121 case RequestSent:
3122 case AckReceived:
3123 next_state = RequestSent;
3124
3125 case AckSent:
3126 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
3127 {
3128 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
3129 sendipv6cp(s, session[s].tunnel);
3130 change_state(s, ipv6cp, next_state);
3131 }
3132 else
3133 {
3134 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
3135 change_state(s, ipv6cp, Stopped);
3136 }
3137
3138 s_actions++;
3139 }
3140 }
3141
3142 if (sess_local[s].ccp.restart <= time_now)
3143 {
3144 int next_state = session[s].ppp.ccp;
3145 switch (session[s].ppp.ccp)
3146 {
3147 case RequestSent:
3148 case AckReceived:
3149 next_state = RequestSent;
3150
3151 case AckSent:
3152 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
3153 {
3154 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
3155 sendccp(s, session[s].tunnel);
3156 change_state(s, ccp, next_state);
3157 }
3158 else
3159 {
3160 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
3161 change_state(s, ccp, Stopped);
3162 }
3163
3164 s_actions++;
3165 }
3166 }
3167
3168 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
3169 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
3170 {
3171 sessionshutdown(s, "No response to LCP ECHO requests.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3172 STAT(session_timeout);
3173 s_actions++;
3174 continue;
3175 }
3176
3177 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
3178 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
3179 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
3180 {
3181 uint8_t b[MAXETHER];
3182
3183 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP, 1, 0, 0);
3184 if (!q) continue;
3185
3186 *q = EchoReq;
3187 *(uint8_t *)(q + 1) = (time_now % 255); // ID
3188 *(uint16_t *)(q + 2) = htons(8); // Length
3189 *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
3190
3191 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
3192 (int)(time_now - session[s].last_packet));
3193 tunnelsend(b, 24, session[s].tunnel); // send it
3194 sess_local[s].last_echo = time_now;
3195 s_actions++;
3196 }
3197
3198 // Check for actions requested from the CLI
3199 if ((a = cli_session_actions[s].action))
3200 {
3201 int send = 0;
3202
3203 cli_session_actions[s].action = 0;
3204 if (a & CLI_SESS_KILL)
3205 {
3206 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
3207 sessionshutdown(s, "Requested by administrator.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
3208 a = 0; // dead, no need to check for other actions
3209 s_actions++;
3210 }
3211
3212 if (a & CLI_SESS_NOSNOOP)
3213 {
3214 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
3215 session[s].snoop_ip = 0;
3216 session[s].snoop_port = 0;
3217 s_actions++;
3218 send++;
3219 }
3220 else if (a & CLI_SESS_SNOOP)
3221 {
3222 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%u)\n",
3223 fmtaddr(cli_session_actions[s].snoop_ip, 0),
3224 cli_session_actions[s].snoop_port);
3225
3226 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
3227 session[s].snoop_port = cli_session_actions[s].snoop_port;
3228 s_actions++;
3229 send++;
3230 }
3231
3232 if (a & CLI_SESS_NOTHROTTLE)
3233 {
3234 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
3235 throttle_session(s, 0, 0);
3236 s_actions++;
3237 send++;
3238 }
3239 else if (a & CLI_SESS_THROTTLE)
3240 {
3241 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
3242 cli_session_actions[s].throttle_in,
3243 cli_session_actions[s].throttle_out);
3244
3245 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
3246 s_actions++;
3247 send++;
3248 }
3249
3250 if (a & CLI_SESS_NOFILTER)
3251 {
3252 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3253 filter_session(s, 0, 0);
3254 s_actions++;
3255 send++;
3256 }
3257 else if (a & CLI_SESS_FILTER)
3258 {
3259 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3260 cli_session_actions[s].filter_in,
3261 cli_session_actions[s].filter_out);
3262
3263 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3264 s_actions++;
3265 send++;
3266 }
3267
3268 if (send)
3269 cluster_send_session(s);
3270 }
3271
3272 // RADIUS interim accounting
3273 if (config->radius_accounting && config->radius_interim > 0
3274 && session[s].ip && !session[s].walled_garden
3275 && !sess_local[s].radius // RADIUS already in progress
3276 && time_now - sess_local[s].last_interim >= config->radius_interim)
3277 {
3278 int rad = radiusnew(s);
3279 if (!rad)
3280 {
3281 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3282 STAT(radius_overflow);
3283 continue;
3284 }
3285
3286 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3287 session[s].user, session[s].unique_id);
3288
3289 radiussend(rad, RADIUSINTERIM);
3290 sess_local[s].last_interim = time_now;
3291 s_actions++;
3292 }
3293 }
3294
3295 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3296 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3297 }
3298
3299 //
3300 // Are we in the middle of a tunnel update, or radius
3301 // requests??
3302 //
3303 static int still_busy(void)
3304 {
3305 int i;
3306 static clockt last_talked = 0;
3307 static clockt start_busy_wait = 0;
3308
3309 if (!config->cluster_iam_master)
3310 {
3311 #ifdef BGP
3312 static time_t stopped_bgp = 0;
3313 if (bgp_configured)
3314 {
3315 if (!stopped_bgp)
3316 {
3317 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3318
3319 for (i = 0; i < BGP_NUM_PEERS; i++)
3320 if (bgp_peers[i].state == Established)
3321 bgp_stop(&bgp_peers[i]);
3322
3323 stopped_bgp = time_now;
3324
3325 // we don't want to become master
3326 cluster_send_ping(0);
3327
3328 return 1;
3329 }
3330
3331 if (time_now < (stopped_bgp + QUIT_DELAY))
3332 return 1;
3333 }
3334 #endif /* BGP */
3335
3336 return 0;
3337 }
3338
3339 if (main_quit == QUIT_SHUTDOWN)
3340 {
3341 static int dropped = 0;
3342 if (!dropped)
3343 {
3344 int i;
3345
3346 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3347 for (i = 1; i < MAXTUNNEL; i++)
3348 if (tunnel[i].ip || tunnel[i].state)
3349 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3350
3351 dropped = 1;
3352 }
3353 }
3354
3355 if (start_busy_wait == 0)
3356 start_busy_wait = TIME;
3357
3358 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3359 {
3360 if (!tunnel[i].controlc)
3361 continue;
3362
3363 if (last_talked != TIME)
3364 {
3365 LOG(2, 0, 0, "Tunnel %u still has un-acked control messages.\n", i);
3366 last_talked = TIME;
3367 }
3368 return 1;
3369 }
3370
3371 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3372 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3373 {
3374 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3375 return 0;
3376 }
3377
3378 for (i = 1; i < MAXRADIUS; i++)
3379 {
3380 if (radius[i].state == RADIUSNULL)
3381 continue;
3382 if (radius[i].state == RADIUSWAIT)
3383 continue;
3384
3385 if (last_talked != TIME)
3386 {
3387 LOG(2, 0, 0, "Radius session %u is still busy (sid %u)\n", i, radius[i].session);
3388 last_talked = TIME;
3389 }
3390 return 1;
3391 }
3392
3393 return 0;
3394 }
3395
3396 #ifdef HAVE_EPOLL
3397 # include <sys/epoll.h>
3398 #else
3399 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3400 # include "fake_epoll.h"
3401 #endif
3402
3403 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3404 #define BASE_FDS 6
3405
3406 // additional polled fds
3407 #ifdef BGP
3408 # define EXTRA_FDS BGP_NUM_PEERS
3409 #else
3410 # define EXTRA_FDS 0
3411 #endif
3412
3413 // main loop - gets packets on tun or udp and processes them
3414 static void mainloop(void)
3415 {
3416 int i;
3417 uint8_t buf[65536];
3418 clockt next_cluster_ping = 0; // send initial ping immediately
3419 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3420 int maxevent = sizeof(events)/sizeof(*events);
3421
3422 if ((epollfd = epoll_create(maxevent)) < 0)
3423 {
3424 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3425 exit(1);
3426 }
3427
3428 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3429 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3430
3431 /* setup our fds to poll for input */
3432 {
3433 static struct event_data d[BASE_FDS];
3434 struct epoll_event e;
3435
3436 e.events = EPOLLIN;
3437 i = 0;
3438
3439 if (clifd >= 0)
3440 {
3441 d[i].type = FD_TYPE_CLI;
3442 e.data.ptr = &d[i++];
3443 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3444 }
3445
3446 d[i].type = FD_TYPE_CLUSTER;
3447 e.data.ptr = &d[i++];
3448 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3449
3450 d[i].type = FD_TYPE_TUN;
3451 e.data.ptr = &d[i++];
3452 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3453
3454 d[i].type = FD_TYPE_UDP;
3455 e.data.ptr = &d[i++];
3456 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3457
3458 d[i].type = FD_TYPE_CONTROL;
3459 e.data.ptr = &d[i++];
3460 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3461
3462 d[i].type = FD_TYPE_DAE;
3463 e.data.ptr = &d[i++];
3464 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3465 }
3466
3467 #ifdef BGP
3468 signal(SIGPIPE, SIG_IGN);
3469 bgp_setup(config->as_number);
3470 if (config->bind_address)
3471 bgp_add_route(config->bind_address, 0xffffffff);
3472
3473 for (i = 0; i < BGP_NUM_PEERS; i++)
3474 {
3475 if (config->neighbour[i].name[0])
3476 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3477 config->neighbour[i].as, config->neighbour[i].keepalive,
3478 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3479 }
3480 #endif /* BGP */
3481
3482 while (!main_quit || still_busy())
3483 {
3484 int more = 0;
3485 int n;
3486
3487
3488 if (main_reload)
3489 {
3490 main_reload = 0;
3491 read_config_file();
3492 config->reload_config++;
3493 }
3494
3495 if (config->reload_config)
3496 {
3497 config->reload_config = 0;
3498 update_config();
3499 }
3500
3501 #ifdef BGP
3502 bgp_set_poll();
3503 #endif /* BGP */
3504
3505 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3506 STAT(select_called);
3507
3508 TIME = now(NULL);
3509 if (n < 0)
3510 {
3511 if (errno == EINTR ||
3512 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3513 continue;
3514
3515 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3516 break; // exit
3517 }
3518
3519 if (n)
3520 {
3521 struct sockaddr_in addr;
3522 struct in_addr local;
3523 socklen_t alen;
3524 int c, s;
3525 int udp_ready = 0;
3526 int tun_ready = 0;
3527 int cluster_ready = 0;
3528 int udp_pkts = 0;
3529 int tun_pkts = 0;
3530 int cluster_pkts = 0;
3531 #ifdef BGP
3532 uint32_t bgp_events[BGP_NUM_PEERS];
3533 memset(bgp_events, 0, sizeof(bgp_events));
3534 #endif /* BGP */
3535
3536 for (c = n, i = 0; i < c; i++)
3537 {
3538 struct event_data *d = events[i].data.ptr;
3539
3540 switch (d->type)
3541 {
3542 case FD_TYPE_CLI: // CLI connections
3543 {
3544 int cli;
3545
3546 alen = sizeof(addr);
3547 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3548 {
3549 cli_do(cli);
3550 close(cli);
3551 }
3552 else
3553 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3554
3555 n--;
3556 break;
3557 }
3558
3559 // these are handled below, with multiple interleaved reads
3560 case FD_TYPE_CLUSTER: cluster_ready++; break;
3561 case FD_TYPE_TUN: tun_ready++; break;
3562 case FD_TYPE_UDP: udp_ready++; break;
3563
3564 case FD_TYPE_CONTROL: // nsctl commands
3565 alen = sizeof(addr);
3566 s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3567 if (s > 0) processcontrol(buf, s, &addr, alen, &local);
3568 n--;
3569 break;
3570
3571 case FD_TYPE_DAE: // DAE requests
3572 alen = sizeof(addr);
3573 s = recvfromto(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3574 if (s > 0) processdae(buf, s, &addr, alen, &local);
3575 n--;
3576 break;
3577
3578 case FD_TYPE_RADIUS: // RADIUS response
3579 alen = sizeof(addr);
3580 s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
3581 if (s >= 0 && config->cluster_iam_master)
3582 {
3583 if (addr.sin_addr.s_addr == config->radiusserver[0] ||
3584 addr.sin_addr.s_addr == config->radiusserver[1])
3585 processrad(buf, s, d->index);
3586 else
3587 LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
3588 fmtaddr(addr.sin_addr.s_addr, 0));
3589 }
3590
3591 n--;
3592 break;
3593
3594 #ifdef BGP
3595 case FD_TYPE_BGP:
3596 bgp_events[d->index] = events[i].events;
3597 n--;
3598 break;
3599 #endif /* BGP */
3600
3601 default:
3602 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3603 }
3604 }
3605
3606 #ifdef BGP
3607 bgp_process(bgp_events);
3608 #endif /* BGP */
3609
3610 for (c = 0; n && c < config->multi_read_count; c++)
3611 {
3612 // L2TP
3613 if (udp_ready)
3614 {
3615 alen = sizeof(addr);
3616 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3617 {
3618 processudp(buf, s, &addr);
3619 udp_pkts++;
3620 }
3621 else
3622 {
3623 udp_ready = 0;
3624 n--;
3625 }
3626 }
3627
3628 // incoming IP
3629 if (tun_ready)
3630 {
3631 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3632 {
3633 processtun(buf, s);
3634 tun_pkts++;
3635 }
3636 else
3637 {
3638 tun_ready = 0;
3639 n--;
3640 }
3641 }
3642
3643 // cluster
3644 if (cluster_ready)
3645 {
3646 alen = sizeof(addr);
3647 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3648 {
3649 processcluster(buf, s, addr.sin_addr.s_addr);
3650 cluster_pkts++;
3651 }
3652 else
3653 {
3654 cluster_ready = 0;
3655 n--;
3656 }
3657 }
3658 }
3659
3660 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3661 STAT(multi_read_used);
3662
3663 if (c >= config->multi_read_count)
3664 {
3665 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3666 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3667
3668 STAT(multi_read_exceeded);
3669 more++;
3670 }
3671 }
3672
3673 if (time_changed)
3674 {
3675 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
3676
3677 // Log current traffic stats
3678 snprintf(config->bandwidth, sizeof(config->bandwidth),
3679 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3680 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
3681 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
3682 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
3683
3684 udp_tx = udp_rx = 0;
3685 udp_rx_pkt = eth_rx_pkt = 0;
3686 eth_tx = eth_rx = 0;
3687 time_changed = 0;
3688
3689 if (config->dump_speed)
3690 printf("%s\n", config->bandwidth);
3691
3692 // Update the internal time counter
3693 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3694
3695 {
3696 // Run timer hooks
3697 struct param_timer p = { time_now };
3698 run_plugins(PLUGIN_TIMER, &p);
3699 }
3700 }
3701
3702 // Runs on every machine (master and slaves).
3703 if (next_cluster_ping <= TIME)
3704 {
3705 // Check to see which of the cluster is still alive..
3706
3707 cluster_send_ping(basetime); // Only does anything if we're a slave
3708 cluster_check_master(); // ditto.
3709
3710 cluster_heartbeat(); // Only does anything if we're a master.
3711 cluster_check_slaves(); // ditto.
3712
3713 master_update_counts(); // If we're a slave, send our byte counters to our master.
3714
3715 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3716 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3717 else
3718 next_cluster_ping = TIME + config->cluster_hb_interval;
3719 }
3720
3721 if (!config->cluster_iam_master)
3722 continue;
3723
3724 // Run token bucket filtering queue..
3725 // Only run it every 1/10th of a second.
3726 {
3727 static clockt last_run = 0;
3728 if (last_run != TIME)
3729 {
3730 last_run = TIME;
3731 tbf_run_timer();
3732 }
3733 }
3734
3735 // Handle timeouts, retries etc.
3736 {
3737 static double last_clean = 0;
3738 double this_clean;
3739 double diff;
3740
3741 TIME = now(&this_clean);
3742 diff = this_clean - last_clean;
3743
3744 // Run during idle time (after we've handled
3745 // all incoming packets) or every 1/10th sec
3746 if (!more || diff > 0.1)
3747 {
3748 regular_cleanups(diff);
3749 last_clean = this_clean;
3750 }
3751 }
3752
3753 if (*config->accounting_dir)
3754 {
3755 static clockt next_acct = 0;
3756 static clockt next_shut_acct = 0;
3757
3758 if (next_acct <= TIME)
3759 {
3760 // Dump accounting data
3761 next_acct = TIME + ACCT_TIME;
3762 next_shut_acct = TIME + ACCT_SHUT_TIME;
3763 dump_acct_info(1);
3764 }
3765 else if (next_shut_acct <= TIME)
3766 {
3767 // Dump accounting data for shutdown sessions
3768 next_shut_acct = TIME + ACCT_SHUT_TIME;
3769 if (shut_acct_n)
3770 dump_acct_info(0);
3771 }
3772 }
3773 }
3774
3775 // Are we the master and shutting down??
3776 if (config->cluster_iam_master)
3777 cluster_heartbeat(); // Flush any queued changes..
3778
3779 // Ok. Notify everyone we're shutting down. If we're
3780 // the master, this will force an election.
3781 cluster_send_ping(0);
3782
3783 //
3784 // Important!!! We MUST not process any packets past this point!
3785 LOG(1, 0, 0, "Shutdown complete\n");
3786 }
3787
3788 static void stripdomain(char *host)
3789 {
3790 char *p;
3791
3792 if ((p = strchr(host, '.')))
3793 {
3794 char *domain = 0;
3795 char _domain[1024];
3796
3797 // strip off domain
3798 FILE *resolv = fopen("/etc/resolv.conf", "r");
3799 if (resolv)
3800 {
3801 char buf[1024];
3802 char *b;
3803
3804 while (fgets(buf, sizeof(buf), resolv))
3805 {
3806 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3807 continue;
3808
3809 if (!isspace(buf[6]))
3810 continue;
3811
3812 b = buf + 7;
3813 while (isspace(*b)) b++;
3814
3815 if (*b)
3816 {
3817 char *d = b;
3818 while (*b && !isspace(*b)) b++;
3819 *b = 0;
3820 if (buf[0] == 'd') // domain is canonical
3821 {
3822 domain = d;
3823 break;
3824 }
3825
3826 // first search line
3827 if (!domain)
3828 {
3829 // hold, may be subsequent domain line
3830 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3831 domain = _domain;
3832 }
3833 }
3834 }
3835
3836 fclose(resolv);
3837 }
3838
3839 if (domain)
3840 {
3841 int hl = strlen(host);
3842 int dl = strlen(domain);
3843 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3844 host[hl -dl - 1] = 0;
3845 }
3846 else
3847 {
3848 *p = 0; // everything after first dot
3849 }
3850 }
3851 }
3852
3853 // Init data structures
3854 static void initdata(int optdebug, char *optconfig)
3855 {
3856 int i;
3857
3858 if (!(config = shared_malloc(sizeof(configt))))
3859 {
3860 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3861 exit(1);
3862 }
3863
3864 memset(config, 0, sizeof(configt));
3865 time(&config->start_time);
3866 strncpy(config->config_file, optconfig, strlen(optconfig));
3867 config->debug = optdebug;
3868 config->num_tbfs = MAXTBFS;
3869 config->rl_rate = 28; // 28kbps
3870 config->cluster_mcast_ttl = 1;
3871 config->cluster_master_min_adv = 1;
3872 config->ppp_restart_time = 3;
3873 config->ppp_max_configure = 10;
3874 config->ppp_max_failure = 5;
3875 strcpy(config->random_device, RANDOMDEVICE);
3876
3877 log_stream = stderr;
3878
3879 #ifdef RINGBUFFER
3880 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3881 {
3882 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3883 exit(1);
3884 }
3885 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3886 #endif
3887
3888 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3889 {
3890 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3891 exit(1);
3892 }
3893 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3894 {
3895 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3896 exit(1);
3897 }
3898 if (!(bundle = shared_malloc(sizeof(bundlet) * MAXBUNDLE)))
3899 {
3900 LOG(0, 0, 0, "Error doing malloc for bundles: %s\n", strerror(errno));
3901 exit(1);
3902 }
3903 if (!(frag = shared_malloc(sizeof(fragmentationt) * MAXBUNDLE)))
3904 {
3905 LOG(0, 0, 0, "Error doing malloc for fragmentations: %s\n", strerror(errno));
3906 exit(1);
3907 }
3908 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3909 {
3910 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3911 exit(1);
3912 }
3913
3914 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3915 {
3916 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3917 exit(1);
3918 }
3919
3920 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3921 {
3922 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3923 exit(1);
3924 }
3925
3926 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3927 {
3928 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3929 exit(1);
3930 }
3931
3932 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3933 {
3934 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3935 exit(1);
3936 }
3937 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3938
3939 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3940 {
3941 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3942 exit(1);
3943 }
3944 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3945
3946 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3947 {
3948 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3949 exit(1);
3950 }
3951 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3952
3953 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3954 memset(bundle, 0, sizeof(bundlet) * MAXBUNDLE);
3955 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3956 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3957 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3958
3959 // Put all the sessions on the free list marked as undefined.
3960 for (i = 1; i < MAXSESSION; i++)
3961 {
3962 session[i].next = i + 1;
3963 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3964 }
3965 session[MAXSESSION - 1].next = 0;
3966 sessionfree = 1;
3967
3968 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3969 for (i = 1; i < MAXTUNNEL; i++)
3970 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3971
3972 for (i = 1; i < MAXBUNDLE; i++) {
3973 bundle[i].state = BUNDLEUNDEF;
3974 }
3975
3976 if (!*hostname)
3977 {
3978 // Grab my hostname unless it's been specified
3979 gethostname(hostname, sizeof(hostname));
3980 stripdomain(hostname);
3981 }
3982
3983 _statistics->start_time = _statistics->last_reset = time(NULL);
3984
3985 #ifdef BGP
3986 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3987 {
3988 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3989 exit(1);
3990 }
3991 #endif /* BGP */
3992 }
3993
3994 static int assign_ip_address(sessionidt s)
3995 {
3996 uint32_t i;
3997 int best = -1;
3998 time_t best_time = time_now;
3999 char *u = session[s].user;
4000 char reuse = 0;
4001
4002
4003 CSTAT(assign_ip_address);
4004
4005 for (i = 1; i < ip_pool_size; i++)
4006 {
4007 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
4008 continue;
4009
4010 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
4011 {
4012 best = i;
4013 reuse = 1;
4014 break;
4015 }
4016
4017 if (ip_address_pool[i].last < best_time)
4018 {
4019 best = i;
4020 if (!(best_time = ip_address_pool[i].last))
4021 break; // never used, grab this one
4022 }
4023 }
4024
4025 if (best < 0)
4026 {
4027 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
4028 return 0;
4029 }
4030
4031 session[s].ip = ip_address_pool[best].address;
4032 session[s].ip_pool_index = best;
4033 ip_address_pool[best].assigned = 1;
4034 ip_address_pool[best].last = time_now;
4035 ip_address_pool[best].session = s;
4036 if (session[s].walled_garden)
4037 /* Don't track addresses of users in walled garden (note: this
4038 means that their address isn't "sticky" even if they get
4039 un-gardened). */
4040 ip_address_pool[best].user[0] = 0;
4041 else
4042 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
4043
4044 STAT(ip_allocated);
4045 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
4046 reuse ? "Reusing" : "Allocating", best);
4047
4048 return 1;
4049 }
4050
4051 static void free_ip_address(sessionidt s)
4052 {
4053 int i = session[s].ip_pool_index;
4054
4055
4056 CSTAT(free_ip_address);
4057
4058 if (!session[s].ip)
4059 return; // what the?
4060
4061 if (i < 0) // Is this actually part of the ip pool?
4062 i = 0;
4063
4064 STAT(ip_freed);
4065 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
4066 session[s].ip = 0;
4067 ip_address_pool[i].assigned = 0;
4068 ip_address_pool[i].session = 0;
4069 ip_address_pool[i].last = time_now;
4070 }
4071
4072 //
4073 // Fsck the address pool against the session table.
4074 // Normally only called when we become a master.
4075 //
4076 // This isn't perfect: We aren't keep tracking of which
4077 // users used to have an IP address.
4078 //
4079 void rebuild_address_pool(void)
4080 {
4081 int i;
4082
4083 //
4084 // Zero the IP pool allocation, and build
4085 // a map from IP address to pool index.
4086 for (i = 1; i < MAXIPPOOL; ++i)
4087 {
4088 ip_address_pool[i].assigned = 0;
4089 ip_address_pool[i].session = 0;
4090 if (!ip_address_pool[i].address)
4091 continue;
4092
4093 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
4094 }
4095
4096 for (i = 0; i < MAXSESSION; ++i)
4097 {
4098 int ipid;
4099 if (!(session[i].opened && session[i].ip))
4100 continue;
4101
4102 ipid = - lookup_ipmap(htonl(session[i].ip));
4103
4104 if (session[i].ip_pool_index < 0)
4105 {
4106 // Not allocated out of the pool.
4107 if (ipid < 1) // Not found in the pool either? good.
4108 continue;
4109
4110 LOG(0, i, 0, "Session %u has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
4111 i, fmtaddr(session[i].ip, 0), ipid);
4112
4113 // Fall through and process it as part of the pool.
4114 }
4115
4116
4117 if (ipid > MAXIPPOOL || ipid < 0)
4118 {
4119 LOG(0, i, 0, "Session %u has a pool IP that's not found in the pool! (%d)\n", i, ipid);
4120 ipid = -1;
4121 session[i].ip_pool_index = ipid;
4122 continue;
4123 }
4124
4125 ip_address_pool[ipid].assigned = 1;
4126 ip_address_pool[ipid].session = i;
4127 ip_address_pool[ipid].last = time_now;
4128 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
4129 session[i].ip_pool_index = ipid;
4130 cache_ipmap(session[i].ip, i); // Fix the ip map.
4131 }
4132 }
4133
4134 //
4135 // Fix the address pool to match a changed session.
4136 // (usually when the master sends us an update).
4137 static void fix_address_pool(int sid)
4138 {
4139 int ipid;
4140
4141 ipid = session[sid].ip_pool_index;
4142
4143 if (ipid > ip_pool_size)
4144 return; // Ignore it. rebuild_address_pool will fix it up.
4145
4146 if (ip_address_pool[ipid].address != session[sid].ip)
4147 return; // Just ignore it. rebuild_address_pool will take care of it.
4148
4149 ip_address_pool[ipid].assigned = 1;
4150 ip_address_pool[ipid].session = sid;
4151 ip_address_pool[ipid].last = time_now;
4152 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
4153 }
4154
4155 //
4156 // Add a block of addresses to the IP pool to hand out.
4157 //
4158 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
4159 {
4160 int i;
4161 if (mask == 0)
4162 mask = 0xffffffff; // Host route only.
4163
4164 addr &= mask;
4165
4166 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
4167 return ;
4168
4169 for (i = addr ;(i & mask) == addr; ++i)
4170 {
4171 if ((i & 0xff) == 0 || (i&0xff) == 255)
4172 continue; // Skip 0 and broadcast addresses.
4173
4174 ip_address_pool[ip_pool_size].address = i;
4175 ip_address_pool[ip_pool_size].assigned = 0;
4176 ++ip_pool_size;
4177 if (ip_pool_size >= MAXIPPOOL)
4178 {
4179 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
4180 return;
4181 }
4182 }
4183 }
4184
4185 // Initialize the IP address pool
4186 static void initippool()
4187 {
4188 FILE *f;
4189 char *p;
4190 char buf[4096];
4191 memset(ip_address_pool, 0, sizeof(ip_address_pool));
4192
4193 if (!(f = fopen(IPPOOLFILE, "r")))
4194 {
4195 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
4196 exit(1);
4197 }
4198
4199 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
4200 {
4201 char *pool = buf;
4202 buf[4095] = 0; // Force it to be zero terminated/
4203
4204 if (*buf == '#' || *buf == '\n')
4205 continue; // Skip comments / blank lines
4206 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
4207 if ((p = (char *)strchr(buf, ':')))
4208 {
4209 in_addr_t src;
4210 *p = '\0';
4211 src = inet_addr(buf);
4212 if (src == INADDR_NONE)
4213 {
4214 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
4215 exit(1);
4216 }
4217 // This entry is for a specific IP only
4218 if (src != config->bind_address)
4219 continue;
4220 *p = ':';
4221 pool = p+1;
4222 }
4223 if ((p = (char *)strchr(pool, '/')))
4224 {
4225 // It's a range
4226 int numbits = 0;
4227 in_addr_t start = 0, mask = 0;
4228
4229 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
4230 *p++ = 0;
4231 if (!*p || !(numbits = atoi(p)))
4232 {
4233 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
4234 continue;
4235 }
4236 start = ntohl(inet_addr(pool));
4237 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
4238
4239 // Add a static route for this pool
4240 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
4241 fmtaddr(htonl(start), 0), 32 + mask);
4242
4243 routeset(0, start, mask, 0, 1);
4244
4245 add_to_ip_pool(start, mask);
4246 }
4247 else
4248 {
4249 // It's a single ip address
4250 add_to_ip_pool(ntohl(inet_addr(pool)), 0);
4251 }
4252 }
4253 fclose(f);
4254 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
4255 }
4256
4257 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
4258 {
4259 struct sockaddr_in snoop_addr = {0};
4260 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
4261 return;
4262
4263 snoop_addr.sin_family = AF_INET;
4264 snoop_addr.sin_addr.s_addr = destination;
4265 snoop_addr.sin_port = ntohs(port);
4266
4267 LOG(5, 0, 0, "Snooping %d byte packet to %s:%u\n", size,
4268 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
4269 htons(snoop_addr.sin_port));
4270
4271 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
4272 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
4273
4274 STAT(packets_snooped);
4275 }
4276
4277 static int dump_session(FILE **f, sessiont *s)
4278 {
4279 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
4280 return 1;
4281
4282 if (!*f)
4283 {
4284 char filename[1024];
4285 char timestr[64];
4286 time_t now = time(NULL);
4287
4288 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4289 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4290
4291 if (!(*f = fopen(filename, "w")))
4292 {
4293 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4294 return 0;
4295 }
4296
4297 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4298 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4299 "# host: %s\n"
4300 "# endpoint: %s\n"
4301 "# time: %ld\n"
4302 "# uptime: %ld\n"
4303 "# format: username ip qos uptxoctets downrxoctets\n",
4304 hostname,
4305 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
4306 now,
4307 now - basetime);
4308 }
4309
4310 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4311 fprintf(*f, "%s %s %d %u %u\n",
4312 s->user, // username
4313 fmtaddr(htonl(s->ip), 0), // ip
4314 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4315 (uint32_t) s->cin_delta, // uptxoctets
4316 (uint32_t) s->cout_delta); // downrxoctets
4317
4318 s->cin_delta = s->cout_delta = 0;
4319
4320 return 1;
4321 }
4322
4323 static void dump_acct_info(int all)
4324 {
4325 int i;
4326 FILE *f = NULL;
4327
4328
4329 CSTAT(dump_acct_info);
4330
4331 if (shut_acct_n)
4332 {
4333 for (i = 0; i < shut_acct_n; i++)
4334 dump_session(&f, &shut_acct[i]);
4335
4336 shut_acct_n = 0;
4337 }
4338
4339 if (all)
4340 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4341 dump_session(&f, &session[i]);
4342
4343 if (f)
4344 fclose(f);
4345 }
4346
4347 // Main program
4348 int main(int argc, char *argv[])
4349 {
4350 int i;
4351 int optdebug = 0;
4352 char *optconfig = CONFIGFILE;
4353
4354 time(&basetime); // start clock
4355
4356 // scan args
4357 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4358 {
4359 switch (i)
4360 {
4361 case 'd':
4362 if (fork()) exit(0);
4363 setsid();
4364 freopen("/dev/null", "r", stdin);
4365 freopen("/dev/null", "w", stdout);
4366 freopen("/dev/null", "w", stderr);
4367 break;
4368 case 'v':
4369 optdebug++;
4370 break;
4371 case 'c':
4372 optconfig = optarg;
4373 break;
4374 case 'h':
4375 snprintf(hostname, sizeof(hostname), "%s", optarg);
4376 break;
4377 default:
4378 printf("Args are:\n"
4379 "\t-d\t\tDetach from terminal\n"
4380 "\t-c <file>\tConfig file\n"
4381 "\t-h <hostname>\tForce hostname\n"
4382 "\t-v\t\tDebug\n");
4383
4384 return (0);
4385 break;
4386 }
4387 }
4388
4389 // Start the timer routine off
4390 time(&time_now);
4391 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4392
4393 initplugins();
4394 initdata(optdebug, optconfig);
4395
4396 init_cli(hostname);
4397 read_config_file();
4398 update_config();
4399 init_tbf(config->num_tbfs);
4400
4401 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4402 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005, 2006 Optus Internet Engineering\n");
4403 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4404 {
4405 struct rlimit rlim;
4406 rlim.rlim_cur = RLIM_INFINITY;
4407 rlim.rlim_max = RLIM_INFINITY;
4408 // Remove the maximum core size
4409 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4410 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4411
4412 // Make core dumps go to /tmp
4413 chdir("/tmp");
4414 }
4415
4416 if (config->scheduler_fifo)
4417 {
4418 int ret;
4419 struct sched_param params = {0};
4420 params.sched_priority = 1;
4421
4422 if (get_nprocs() < 2)
4423 {
4424 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4425 config->scheduler_fifo = 0;
4426 }
4427 else
4428 {
4429 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4430 {
4431 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4432 }
4433 else
4434 {
4435 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4436 config->scheduler_fifo = 0;
4437 }
4438 }
4439 }
4440
4441 /* Set up the cluster communications port. */
4442 if (cluster_init() < 0)
4443 exit(1);
4444
4445 inittun();
4446 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4447
4448 initudp();
4449 initrad();
4450 initippool();
4451
4452 // seed prng
4453 {
4454 unsigned seed = time_now ^ getpid();
4455 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4456 srand(seed);
4457 }
4458
4459 signal(SIGHUP, sighup_handler);
4460 signal(SIGCHLD, sigchild_handler);
4461 signal(SIGTERM, shutdown_handler);
4462 signal(SIGINT, shutdown_handler);
4463 signal(SIGQUIT, shutdown_handler);
4464
4465 // Prevent us from getting paged out
4466 if (config->lock_pages)
4467 {
4468 if (!mlockall(MCL_CURRENT))
4469 LOG(1, 0, 0, "Locking pages into memory\n");
4470 else
4471 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4472 }
4473
4474 mainloop();
4475
4476 /* remove plugins (so cleanup code gets run) */
4477 plugins_done();
4478
4479 // Remove the PID file if we wrote it
4480 if (config->wrote_pid && *config->pid_file == '/')
4481 unlink(config->pid_file);
4482
4483 /* kill CLI children */
4484 signal(SIGTERM, SIG_IGN);
4485 kill(0, SIGTERM);
4486 return 0;
4487 }
4488
4489 static void sighup_handler(int sig)
4490 {
4491 main_reload++;
4492 }
4493
4494 static void shutdown_handler(int sig)
4495 {
4496 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4497 }
4498
4499 static void sigchild_handler(int sig)
4500 {
4501 while (waitpid(-1, NULL, WNOHANG) > 0)
4502 ;
4503 }
4504
4505 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4506 {
4507 MD5_CTX ctx;
4508 *challenge_response = NULL;
4509
4510 if (!*config->l2tp_secret)
4511 {
4512 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4513 return;
4514 }
4515
4516 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4517
4518 *challenge_response = calloc(17, 1);
4519
4520 MD5_Init(&ctx);
4521 MD5_Update(&ctx, &id, 1);
4522 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4523 MD5_Update(&ctx, challenge, challenge_length);
4524 MD5_Final(*challenge_response, &ctx);
4525
4526 return;
4527 }
4528
4529 static int facility_value(char *name)
4530 {
4531 int i;
4532 for (i = 0; facilitynames[i].c_name; i++)
4533 {
4534 if (strcmp(facilitynames[i].c_name, name) == 0)
4535 return facilitynames[i].c_val;
4536 }
4537 return 0;
4538 }
4539
4540 static void update_config()
4541 {
4542 int i;
4543 char *p;
4544 static int timeout = 0;
4545 static int interval = 0;
4546
4547 // Update logging
4548 closelog();
4549 syslog_log = 0;
4550 if (log_stream)
4551 {
4552 if (log_stream != stderr)
4553 fclose(log_stream);
4554
4555 log_stream = NULL;
4556 }
4557
4558 if (*config->log_filename)
4559 {
4560 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4561 {
4562 char *p = config->log_filename + 7;
4563 if (*p)
4564 {
4565 openlog("l2tpns", LOG_PID, facility_value(p));
4566 syslog_log = 1;
4567 }
4568 }
4569 else if (strchr(config->log_filename, '/') == config->log_filename)
4570 {
4571 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4572 {
4573 fseek(log_stream, 0, SEEK_END);
4574 setbuf(log_stream, NULL);
4575 }
4576 else
4577 {
4578 log_stream = stderr;
4579 setbuf(log_stream, NULL);
4580 }
4581 }
4582 }
4583 else
4584 {
4585 log_stream = stderr;
4586 setbuf(log_stream, NULL);
4587 }
4588
4589 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4590 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4591
4592 if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
4593 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4594 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4595
4596 // reset MRU/MSS globals
4597 MRU = config->l2tp_mtu - L2TP_HDRS;
4598 if (MRU > PPPoE_MRU)
4599 MRU = PPPoE_MRU;
4600
4601 MSS = MRU - TCP_HDRS;
4602
4603 // Update radius
4604 config->numradiusservers = 0;
4605 for (i = 0; i < MAXRADSERVER; i++)
4606 if (config->radiusserver[i])
4607 {
4608 config->numradiusservers++;
4609 // Set radius port: if not set, take the port from the
4610 // first radius server. For the first radius server,
4611 // take the #defined default value from l2tpns.h
4612
4613 // test twice, In case someone works with
4614 // a secondary radius server without defining
4615 // a primary one, this will work even then.
4616 if (i > 0 && !config->radiusport[i])
4617 config->radiusport[i] = config->radiusport[i-1];
4618 if (!config->radiusport[i])
4619 config->radiusport[i] = RADPORT;
4620 }
4621
4622 if (!config->numradiusservers)
4623 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4624
4625 // parse radius_authtypes_s
4626 config->radius_authtypes = config->radius_authprefer = 0;
4627 p = config->radius_authtypes_s;
4628 while (p && *p)
4629 {
4630 char *s = strpbrk(p, " \t,");
4631 int type = 0;
4632
4633 if (s)
4634 {
4635 *s++ = 0;
4636 while (*s == ' ' || *s == '\t')
4637 s++;
4638
4639 if (!*s)
4640 s = 0;
4641 }
4642
4643 if (!strncasecmp("chap", p, strlen(p)))
4644 type = AUTHCHAP;
4645 else if (!strncasecmp("pap", p, strlen(p)))
4646 type = AUTHPAP;
4647 else
4648 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4649
4650 config->radius_authtypes |= type;
4651 if (!config->radius_authprefer)
4652 config->radius_authprefer = type;
4653
4654 p = s;
4655 }
4656
4657 if (!config->radius_authtypes)
4658 {
4659 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4660 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4661 }
4662
4663 // normalise radius_authtypes_s
4664 if (config->radius_authprefer == AUTHPAP)
4665 {
4666 strcpy(config->radius_authtypes_s, "pap");
4667 if (config->radius_authtypes & AUTHCHAP)
4668 strcat(config->radius_authtypes_s, ", chap");
4669 }
4670 else
4671 {
4672 strcpy(config->radius_authtypes_s, "chap");
4673 if (config->radius_authtypes & AUTHPAP)
4674 strcat(config->radius_authtypes_s, ", pap");
4675 }
4676
4677 if (!config->radius_dae_port)
4678 config->radius_dae_port = DAEPORT;
4679
4680 // re-initialise the random number source
4681 initrandom(config->random_device);
4682
4683 // Update plugins
4684 for (i = 0; i < MAXPLUGINS; i++)
4685 {
4686 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4687 continue;
4688
4689 if (*config->plugins[i])
4690 {
4691 // Plugin added
4692 add_plugin(config->plugins[i]);
4693 }
4694 else if (*config->old_plugins[i])
4695 {
4696 // Plugin removed
4697 remove_plugin(config->old_plugins[i]);
4698 }
4699 }
4700
4701 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4702 if (!config->multi_read_count) config->multi_read_count = 10;
4703 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4704 if (!*config->cluster_interface)
4705 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4706
4707 if (!config->cluster_hb_interval)
4708 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4709
4710 if (!config->cluster_hb_timeout)
4711 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4712
4713 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4714 {
4715 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4716 // late, ensure we're sufficiently larger than that
4717 int t = 4 * config->cluster_hb_interval + 11;
4718
4719 if (config->cluster_hb_timeout < t)
4720 {
4721 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4722 config->cluster_hb_timeout = t;
4723 }
4724
4725 // Push timing changes to the slaves immediately if we're the master
4726 if (config->cluster_iam_master)
4727 cluster_heartbeat();
4728
4729 interval = config->cluster_hb_interval;
4730 timeout = config->cluster_hb_timeout;
4731 }
4732
4733 // Write PID file
4734 if (*config->pid_file == '/' && !config->wrote_pid)
4735 {
4736 FILE *f;
4737 if ((f = fopen(config->pid_file, "w")))
4738 {
4739 fprintf(f, "%d\n", getpid());
4740 fclose(f);
4741 config->wrote_pid = 1;
4742 }
4743 else
4744 {
4745 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4746 }
4747 }
4748 }
4749
4750 static void read_config_file()
4751 {
4752 FILE *f;
4753
4754 if (!config->config_file) return;
4755 if (!(f = fopen(config->config_file, "r")))
4756 {
4757 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4758 return;
4759 }
4760
4761 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4762 cli_do_file(f);
4763 LOG(3, 0, 0, "Done reading config file\n");
4764 fclose(f);
4765 }
4766
4767 int sessionsetup(sessionidt s, tunnelidt t)
4768 {
4769 // A session now exists, set it up
4770 in_addr_t ip;
4771 char *user;
4772 sessionidt i;
4773 int r;
4774
4775 CSTAT(sessionsetup);
4776
4777 LOG(3, s, t, "Doing session setup for session\n");
4778
4779 if (!session[s].ip)
4780 {
4781 assign_ip_address(s);
4782 if (!session[s].ip)
4783 {
4784 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4785 sessionshutdown(s, "No IP addresses available.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
4786 return 0;
4787 }
4788 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4789 fmtaddr(htonl(session[s].ip), 0));
4790 }
4791
4792
4793 // Make sure this is right
4794 session[s].tunnel = t;
4795
4796 // Join a bundle if the MRRU option is accepted
4797 if (session[s].mrru > 0 && !session[s].bundle)
4798 {
4799 LOG(3, s, t, "This session can be part of multilink bundle\n");
4800 if (join_bundle(s))
4801 cluster_send_bundle(session[s].bundle);
4802 }
4803
4804 // zap old sessions with same IP and/or username
4805 // Don't kill gardened sessions - doing so leads to a DoS
4806 // from someone who doesn't need to know the password
4807 {
4808 ip = session[s].ip;
4809 user = session[s].user;
4810 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4811 {
4812 if (i == s) continue;
4813 if (!session[s].opened) continue;
4814 if (ip == session[i].ip)
4815 {
4816 sessionkill(i, "Duplicate IP address");
4817 continue;
4818 }
4819
4820 if (config->allow_duplicate_users)
4821 continue;
4822
4823 if (session[s].walled_garden || session[i].walled_garden)
4824 continue;
4825
4826 // Allow duplicate sessions for guest account.
4827 if (*config->guest_user && !strcasecmp(user, config->guest_user))
4828 continue;
4829
4830 // Allow duplicate sessions for multilink ones of the same bundle.
4831 if (session[s].bundle && session[i].bundle && session[s].bundle == session[i].bundle)
4832 continue;
4833
4834 // Drop the new session in case of duplicate sessionss, not the old one.
4835 if (!strcasecmp(user, session[i].user))
4836 sessionkill(i, "Duplicate session for users");
4837 }
4838 }
4839
4840 {
4841 int routed = 0;
4842
4843 // Add the route for this session.
4844 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4845 {
4846 if ((session[s].ip & session[s].route[r].mask) ==
4847 (session[s].route[r].ip & session[s].route[r].mask))
4848 routed++;
4849
4850 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4851 }
4852
4853 // Static IPs need to be routed if not already
4854 // convered by a Framed-Route. Anything else is part
4855 // of the IP address pool and is already routed, it
4856 // just needs to be added to the IP cache.
4857 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4858 if (session[s].ip_pool_index == -1) // static ip
4859 {
4860 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4861 }
4862 else
4863 cache_ipmap(session[s].ip, s);
4864 }
4865
4866 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4867 lcp_open(s, t); // transition to Network phase and send initial IPCP
4868
4869 // Run the plugin's against this new session.
4870 {
4871 struct param_new_session data = { &tunnel[t], &session[s] };
4872 run_plugins(PLUGIN_NEW_SESSION, &data);
4873 }
4874
4875 // Allocate TBFs if throttled
4876 if (session[s].throttle_in || session[s].throttle_out)
4877 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4878
4879 session[s].last_packet = time_now;
4880
4881 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4882 fmtaddr(htonl(session[s].ip), 0),
4883 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4884
4885 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4886
4887 return 1; // RADIUS OK and IP allocated, done...
4888 }
4889
4890 //
4891 // This session just got dropped on us by the master or something.
4892 // Make sure our tables up up to date...
4893 //
4894 int load_session(sessionidt s, sessiont *new)
4895 {
4896 int i;
4897 int newip = 0;
4898
4899 // Sanity checks.
4900 if (new->ip_pool_index >= MAXIPPOOL ||
4901 new->tunnel >= MAXTUNNEL)
4902 {
4903 LOG(0, s, 0, "Strange session update received!\n");
4904 // FIXME! What to do here?
4905 return 0;
4906 }
4907
4908 //
4909 // Ok. All sanity checks passed. Now we're committed to
4910 // loading the new session.
4911 //
4912
4913 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4914
4915 // See if routes/ip cache need updating
4916 if (new->ip != session[s].ip)
4917 newip++;
4918
4919 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4920 if (new->route[i].ip != session[s].route[i].ip ||
4921 new->route[i].mask != session[s].route[i].mask)
4922 newip++;
4923
4924 // needs update
4925 if (newip)
4926 {
4927 int routed = 0;
4928
4929 // remove old routes...
4930 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4931 {
4932 if ((session[s].ip & session[s].route[i].mask) ==
4933 (session[s].route[i].ip & session[s].route[i].mask))
4934 routed++;
4935
4936 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4937 }
4938
4939 // ...ip
4940 if (session[s].ip)
4941 {
4942 if (session[s].ip_pool_index == -1) // static IP
4943 {
4944 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4945 }
4946 else // It's part of the IP pool, remove it manually.
4947 uncache_ipmap(session[s].ip);
4948 }
4949
4950 routed = 0;
4951
4952 // add new routes...
4953 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4954 {
4955 if ((new->ip & new->route[i].mask) ==
4956 (new->route[i].ip & new->route[i].mask))
4957 routed++;
4958
4959 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4960 }
4961
4962 // ...ip
4963 if (new->ip)
4964 {
4965 // If there's a new one, add it.
4966 if (new->ip_pool_index == -1)
4967 {
4968 if (!routed) routeset(s, new->ip, 0, 0, 1);
4969 }
4970 else
4971 cache_ipmap(new->ip, s);
4972 }
4973 }
4974
4975 // check v6 routing
4976 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4977 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4978
4979 // check filters
4980 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4981 {
4982 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %u\n", (int) new->filter_in);
4983 new->filter_in = 0;
4984 }
4985
4986 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4987 {
4988 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %u\n", (int) new->filter_out);
4989 new->filter_out = 0;
4990 }
4991
4992 if (new->filter_in != session[s].filter_in)
4993 {
4994 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4995 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4996 }
4997
4998 if (new->filter_out != session[s].filter_out)
4999 {
5000 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
5001 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
5002 }
5003
5004 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
5005 // for walking the sessions to forward byte counts to the master.
5006 config->cluster_highest_sessionid = s;
5007
5008 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
5009
5010 // Do fixups into address pool.
5011 if (new->ip_pool_index != -1)
5012 fix_address_pool(s);
5013
5014 return 1;
5015 }
5016
5017 static void initplugins()
5018 {
5019 int i;
5020
5021 loaded_plugins = ll_init();
5022 // Initialize the plugins to nothing
5023 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
5024 plugins[i] = ll_init();
5025 }
5026
5027 static void *open_plugin(char *plugin_name, int load)
5028 {
5029 char path[256] = "";
5030
5031 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
5032 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
5033 return dlopen(path, RTLD_NOW);
5034 }
5035
5036 // plugin callback to get a config value
5037 static void *getconfig(char *key, enum config_typet type)
5038 {
5039 int i;
5040
5041 for (i = 0; config_values[i].key; i++)
5042 {
5043 if (!strcmp(config_values[i].key, key))
5044 {
5045 if (config_values[i].type == type)
5046 return ((void *) config) + config_values[i].offset;
5047
5048 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
5049 key, type, config_values[i].type);
5050
5051 return 0;
5052 }
5053 }
5054
5055 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
5056 return 0;
5057 }
5058
5059 static int add_plugin(char *plugin_name)
5060 {
5061 static struct pluginfuncs funcs = {
5062 _log,
5063 _log_hex,
5064 fmtaddr,
5065 sessionbyuser,
5066 sessiontbysessionidt,
5067 sessionidtbysessiont,
5068 radiusnew,
5069 radiussend,
5070 getconfig,
5071 sessionshutdown,
5072 sessionkill,
5073 throttle_session,
5074 cluster_send_session,
5075 };
5076
5077 void *p = open_plugin(plugin_name, 1);
5078 int (*initfunc)(struct pluginfuncs *);
5079 int i;
5080
5081 if (!p)
5082 {
5083 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
5084 return -1;
5085 }
5086
5087 if (ll_contains(loaded_plugins, p))
5088 {
5089 dlclose(p);
5090 return 0; // already loaded
5091 }
5092
5093 {
5094 int *v = dlsym(p, "plugin_api_version");
5095 if (!v || *v != PLUGIN_API_VERSION)
5096 {
5097 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
5098 dlclose(p);
5099 return -1;
5100 }
5101 }
5102
5103 if ((initfunc = dlsym(p, "plugin_init")))
5104 {
5105 if (!initfunc(&funcs))
5106 {
5107 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
5108 dlclose(p);
5109 return -1;
5110 }
5111 }
5112
5113 ll_push(loaded_plugins, p);
5114
5115 for (i = 0; i < max_plugin_functions; i++)
5116 {
5117 void *x;
5118 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5119 {
5120 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
5121 ll_push(plugins[i], x);
5122 }
5123 }
5124
5125 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
5126 return 1;
5127 }
5128
5129 static void run_plugin_done(void *plugin)
5130 {
5131 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
5132
5133 if (donefunc)
5134 donefunc();
5135 }
5136
5137 static int remove_plugin(char *plugin_name)
5138 {
5139 void *p = open_plugin(plugin_name, 0);
5140 int loaded = 0;
5141
5142 if (!p)
5143 return -1;
5144
5145 if (ll_contains(loaded_plugins, p))
5146 {
5147 int i;
5148 for (i = 0; i < max_plugin_functions; i++)
5149 {
5150 void *x;
5151 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5152 ll_delete(plugins[i], x);
5153 }
5154
5155 ll_delete(loaded_plugins, p);
5156 run_plugin_done(p);
5157 loaded = 1;
5158 }
5159
5160 dlclose(p);
5161 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
5162 return loaded;
5163 }
5164
5165 int run_plugins(int plugin_type, void *data)
5166 {
5167 int (*func)(void *data);
5168
5169 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
5170 return PLUGIN_RET_ERROR;
5171
5172 ll_reset(plugins[plugin_type]);
5173 while ((func = ll_next(plugins[plugin_type])))
5174 {
5175 int r = func(data);
5176
5177 if (r != PLUGIN_RET_OK)
5178 return r; // stop here
5179 }
5180
5181 return PLUGIN_RET_OK;
5182 }
5183
5184 static void plugins_done()
5185 {
5186 void *p;
5187
5188 ll_reset(loaded_plugins);
5189 while ((p = ll_next(loaded_plugins)))
5190 run_plugin_done(p);
5191 }
5192
5193 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
5194 {
5195 struct nsctl request;
5196 struct nsctl response;
5197 int type = unpack_control(&request, buf, len);
5198 int r;
5199 void *p;
5200
5201 if (log_stream && config->debug >= 4)
5202 {
5203 if (type < 0)
5204 {
5205 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
5206 fmtaddr(addr->sin_addr.s_addr, 0), type);
5207 }
5208 else
5209 {
5210 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5211 dump_control(&request, log_stream);
5212 }
5213 }
5214
5215 switch (type)
5216 {
5217 case NSCTL_REQ_LOAD:
5218 if (request.argc != 1)
5219 {
5220 response.type = NSCTL_RES_ERR;
5221 response.argc = 1;
5222 response.argv[0] = "name of plugin required";
5223 }
5224 else if ((r = add_plugin(request.argv[0])) < 1)
5225 {
5226 response.type = NSCTL_RES_ERR;
5227 response.argc = 1;
5228 response.argv[0] = !r
5229 ? "plugin already loaded"
5230 : "error loading plugin";
5231 }
5232 else
5233 {
5234 response.type = NSCTL_RES_OK;
5235 response.argc = 0;
5236 }
5237
5238 break;
5239
5240 case NSCTL_REQ_UNLOAD:
5241 if (request.argc != 1)
5242 {
5243 response.type = NSCTL_RES_ERR;
5244 response.argc = 1;
5245 response.argv[0] = "name of plugin required";
5246 }
5247 else if ((r = remove_plugin(request.argv[0])) < 1)
5248 {
5249 response.type = NSCTL_RES_ERR;
5250 response.argc = 1;
5251 response.argv[0] = !r
5252 ? "plugin not loaded"
5253 : "plugin not found";
5254 }
5255 else
5256 {
5257 response.type = NSCTL_RES_OK;
5258 response.argc = 0;
5259 }
5260
5261 break;
5262
5263 case NSCTL_REQ_HELP:
5264 response.type = NSCTL_RES_OK;
5265 response.argc = 0;
5266
5267 ll_reset(loaded_plugins);
5268 while ((p = ll_next(loaded_plugins)))
5269 {
5270 char **help = dlsym(p, "plugin_control_help");
5271 while (response.argc < 0xff && help && *help)
5272 response.argv[response.argc++] = *help++;
5273 }
5274
5275 break;
5276
5277 case NSCTL_REQ_CONTROL:
5278 {
5279 struct param_control param = {
5280 config->cluster_iam_master,
5281 request.argc,
5282 request.argv,
5283 0,
5284 NULL,
5285 };
5286
5287 int r = run_plugins(PLUGIN_CONTROL, &param);
5288
5289 if (r == PLUGIN_RET_ERROR)
5290 {
5291 response.type = NSCTL_RES_ERR;
5292 response.argc = 1;
5293 response.argv[0] = param.additional
5294 ? param.additional
5295 : "error returned by plugin";
5296 }
5297 else if (r == PLUGIN_RET_NOTMASTER)
5298 {
5299 static char msg[] = "must be run on master: 000.000.000.000";
5300
5301 response.type = NSCTL_RES_ERR;
5302 response.argc = 1;
5303 if (config->cluster_master_address)
5304 {
5305 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5306 response.argv[0] = msg;
5307 }
5308 else
5309 {
5310 response.argv[0] = "must be run on master: none elected";
5311 }
5312 }
5313 else if (!(param.response & NSCTL_RESPONSE))
5314 {
5315 response.type = NSCTL_RES_ERR;
5316 response.argc = 1;
5317 response.argv[0] = param.response
5318 ? "unrecognised response value from plugin"
5319 : "unhandled action";
5320 }
5321 else
5322 {
5323 response.type = param.response;
5324 response.argc = 0;
5325 if (param.additional)
5326 {
5327 response.argc = 1;
5328 response.argv[0] = param.additional;
5329 }
5330 }
5331 }
5332
5333 break;
5334
5335 default:
5336 response.type = NSCTL_RES_ERR;
5337 response.argc = 1;
5338 response.argv[0] = "error unpacking control packet";
5339 }
5340
5341 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5342 if (!buf)
5343 {
5344 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5345 return;
5346 }
5347
5348 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5349 if (r > 0)
5350 {
5351 sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
5352 if (log_stream && config->debug >= 4)
5353 {
5354 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5355 dump_control(&response, log_stream);
5356 }
5357 }
5358 else
5359 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5360 fmtaddr(addr->sin_addr.s_addr, 0), r);
5361
5362 free(buf);
5363 }
5364
5365 static tunnelidt new_tunnel()
5366 {
5367 tunnelidt i;
5368 for (i = 1; i < MAXTUNNEL; i++)
5369 {
5370 if (tunnel[i].state == TUNNELFREE)
5371 {
5372 LOG(4, 0, i, "Assigning tunnel ID %u\n", i);
5373 if (i > config->cluster_highest_tunnelid)
5374 config->cluster_highest_tunnelid = i;
5375 return i;
5376 }
5377 }
5378 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5379 return 0;
5380 }
5381
5382 //
5383 // We're becoming the master. Do any required setup..
5384 //
5385 // This is principally telling all the plugins that we're
5386 // now a master, and telling them about all the sessions
5387 // that are active too..
5388 //
5389 void become_master(void)
5390 {
5391 int s, i;
5392 static struct event_data d[RADIUS_FDS];
5393 struct epoll_event e;
5394
5395 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5396
5397 // running a bunch of iptables commands is slow and can cause
5398 // the master to drop tunnels on takeover--kludge around the
5399 // problem by forking for the moment (note: race)
5400 if (!fork_and_close())
5401 {
5402 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5403 {
5404 if (!session[s].opened) // Not an in-use session.
5405 continue;
5406
5407 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5408 }
5409 exit(0);
5410 }
5411
5412 // add radius fds
5413 e.events = EPOLLIN;
5414 for (i = 0; i < RADIUS_FDS; i++)
5415 {
5416 d[i].type = FD_TYPE_RADIUS;
5417 d[i].index = i;
5418 e.data.ptr = &d[i];
5419
5420 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5421 }
5422 }
5423
5424 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5425 {
5426 int s, i;
5427 int count = 0;
5428 int buckets[64];
5429
5430 if (CLI_HELP_REQUESTED)
5431 return CLI_HELP_NO_ARGS;
5432
5433 time(&time_now);
5434 for (i = 0; i < 64;++i) buckets[i] = 0;
5435
5436 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5437 {
5438 int idle;
5439 if (!session[s].opened)
5440 continue;
5441
5442 idle = time_now - session[s].last_packet;
5443 idle /= 5 ; // In multiples of 5 seconds.
5444 if (idle < 0)
5445 idle = 0;
5446 if (idle > 63)
5447 idle = 63;
5448
5449 ++count;
5450 ++buckets[idle];
5451 }
5452
5453 for (i = 0; i < 63; ++i)
5454 {
5455 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5456 }
5457 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5458 cli_print(cli, "%d total sessions open.", count);
5459 return CLI_OK;
5460 }
5461
5462 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5463 {
5464 int s, i;
5465 int count = 0;
5466 int buckets[64];
5467
5468 if (CLI_HELP_REQUESTED)
5469 return CLI_HELP_NO_ARGS;
5470
5471 time(&time_now);
5472 for (i = 0; i < 64;++i) buckets[i] = 0;
5473
5474 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5475 {
5476 int open = 0, d;
5477 if (!session[s].opened)
5478 continue;
5479
5480 d = time_now - session[s].opened;
5481 if (d < 0)
5482 d = 0;
5483 while (d > 1 && open < 32)
5484 {
5485 ++open;
5486 d >>= 1; // half.
5487 }
5488 ++count;
5489 ++buckets[open];
5490 }
5491
5492 s = 1;
5493 for (i = 0; i < 30; ++i)
5494 {
5495 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5496 s <<= 1;
5497 }
5498 cli_print(cli, "%d total sessions open.", count);
5499 return CLI_OK;
5500 }
5501
5502 /* Unhide an avp.
5503 *
5504 * This unencodes the AVP using the L2TP secret and the previously
5505 * stored random vector. It overwrites the hidden data with the
5506 * unhidden AVP subformat.
5507 */
5508 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5509 {
5510 MD5_CTX ctx;
5511 uint8_t digest[16];
5512 uint8_t *last;
5513 size_t d = 0;
5514 uint16_t m = htons(type);
5515
5516 // Compute initial pad
5517 MD5_Init(&ctx);
5518 MD5_Update(&ctx, (unsigned char *) &m, 2);
5519 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5520 MD5_Update(&ctx, vector, vec_len);
5521 MD5_Final(digest, &ctx);
5522
5523 // pointer to last decoded 16 octets
5524 last = value;
5525
5526 while (len > 0)
5527 {
5528 // calculate a new pad based on the last decoded block
5529 if (d >= sizeof(digest))
5530 {
5531 MD5_Init(&ctx);
5532 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5533 MD5_Update(&ctx, last, sizeof(digest));
5534 MD5_Final(digest, &ctx);
5535
5536 d = 0;
5537 last = value;
5538 }
5539
5540 *value++ ^= digest[d++];
5541 len--;
5542 }
5543 }
5544
5545 int find_filter(char const *name, size_t len)
5546 {
5547 int free = -1;
5548 int i;
5549
5550 for (i = 0; i < MAXFILTER; i++)
5551 {
5552 if (!*ip_filters[i].name)
5553 {
5554 if (free < 0)
5555 free = i;
5556
5557 continue;
5558 }
5559
5560 if (strlen(ip_filters[i].name) != len)
5561 continue;
5562
5563 if (!strncmp(ip_filters[i].name, name, len))
5564 return i;
5565 }
5566
5567 return free;
5568 }
5569
5570 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5571 {
5572 switch (p->op)
5573 {
5574 case FILTER_PORT_OP_EQ: return port == p->port;
5575 case FILTER_PORT_OP_NEQ: return port != p->port;
5576 case FILTER_PORT_OP_GT: return port > p->port;
5577 case FILTER_PORT_OP_LT: return port < p->port;
5578 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5579 }
5580
5581 return 0;
5582 }
5583
5584 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5585 {
5586 switch (op)
5587 {
5588 case FILTER_FLAG_OP_ANY:
5589 return (flags & sflags) || (~flags & cflags);
5590
5591 case FILTER_FLAG_OP_ALL:
5592 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5593
5594 case FILTER_FLAG_OP_EST:
5595 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5596 }
5597
5598 return 0;
5599 }
5600
5601 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5602 {
5603 uint16_t frag_offset;
5604 uint8_t proto;
5605 in_addr_t src_ip;
5606 in_addr_t dst_ip;
5607 uint16_t src_port = 0;
5608 uint16_t dst_port = 0;
5609 uint8_t flags = 0;
5610 ip_filter_rulet *rule;
5611
5612 if (len < 20) // up to end of destination address
5613 return 0;
5614
5615 if ((*buf >> 4) != 4) // IPv4
5616 return 0;
5617
5618 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5619 proto = buf[9];
5620 src_ip = *(in_addr_t *) (buf + 12);
5621 dst_ip = *(in_addr_t *) (buf + 16);
5622
5623 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5624 {
5625 int l = (buf[0] & 0xf) * 4; // length of IP header
5626 if (len < l + 4) // ports
5627 return 0;
5628
5629 src_port = ntohs(*(uint16_t *) (buf + l));
5630 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5631 if (proto == IPPROTO_TCP)
5632 {
5633 if (len < l + 14) // flags
5634 return 0;
5635
5636 flags = buf[l + 13] & 0x3f;
5637 }
5638 }
5639
5640 for (rule = ip_filters[filter].rules; rule->action; rule++)
5641 {
5642 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5643 continue;
5644
5645 if (rule->src_wild != INADDR_BROADCAST &&
5646 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5647 continue;
5648
5649 if (rule->dst_wild != INADDR_BROADCAST &&
5650 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5651 continue;
5652
5653 if (frag_offset)
5654 {
5655 // layer 4 deny rules are skipped
5656 if (rule->action == FILTER_ACTION_DENY &&
5657 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
5658 continue;
5659 }
5660 else
5661 {
5662 if (rule->frag)
5663 continue;
5664
5665 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5666 {
5667 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5668 continue;
5669
5670 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5671 continue;
5672
5673 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5674 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5675 continue;
5676 }
5677 }
5678
5679 // matched
5680 rule->counter++;
5681 return rule->action == FILTER_ACTION_PERMIT;
5682 }
5683
5684 // default deny
5685 return 0;
5686 }