03e780cd1b0e887cb9545ac0363db9fea1a4be86
[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 1.168 2006-06-22 15:30:29 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 // calculated from config->l2tp_mtu
79 uint16_t MRU = 0; // PPP MRU
80 uint16_t MSS = 0; // TCP MSS
81
82 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
83 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
84
85 static void *ip_hash[256]; // Mapping from IP address to session structures.
86 struct ipv6radix {
87 int sess;
88 struct ipv6radix *branch;
89 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
90
91 // Traffic counters.
92 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
93 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
94 uint32_t eth_tx = 0;
95
96 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
97 time_t time_now = 0; // Current time in seconds since epoch.
98 static char time_now_string[64] = {0}; // Current time as a string.
99 static int time_changed = 0; // time_now changed
100 char main_quit = 0; // True if we're in the process of exiting.
101 static char main_reload = 0; // Re-load pending
102 linked_list *loaded_plugins;
103 linked_list *plugins[MAX_PLUGIN_TYPES];
104
105 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
106 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
107
108 config_descriptt config_values[] = {
109 CONFIG("debug", debug, INT),
110 CONFIG("log_file", log_filename, STRING),
111 CONFIG("pid_file", pid_file, STRING),
112 CONFIG("random_device", random_device, STRING),
113 CONFIG("l2tp_secret", l2tp_secret, STRING),
114 CONFIG("l2tp_mtu", l2tp_mtu, INT),
115 CONFIG("ppp_restart_time", ppp_restart_time, INT),
116 CONFIG("ppp_max_configure", ppp_max_configure, INT),
117 CONFIG("ppp_max_failure", ppp_max_failure, INT),
118 CONFIG("primary_dns", default_dns1, IPv4),
119 CONFIG("secondary_dns", default_dns2, IPv4),
120 CONFIG("primary_radius", radiusserver[0], IPv4),
121 CONFIG("secondary_radius", radiusserver[1], IPv4),
122 CONFIG("primary_radius_port", radiusport[0], SHORT),
123 CONFIG("secondary_radius_port", radiusport[1], SHORT),
124 CONFIG("radius_accounting", radius_accounting, BOOL),
125 CONFIG("radius_interim", radius_interim, INT),
126 CONFIG("radius_secret", radiussecret, STRING),
127 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
128 CONFIG("radius_dae_port", radius_dae_port, SHORT),
129 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
130 CONFIG("guest_account", guest_user, STRING),
131 CONFIG("bind_address", bind_address, IPv4),
132 CONFIG("peer_address", peer_address, IPv4),
133 CONFIG("send_garp", send_garp, BOOL),
134 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
135 CONFIG("throttle_buckets", num_tbfs, INT),
136 CONFIG("accounting_dir", accounting_dir, STRING),
137 CONFIG("dump_speed", dump_speed, BOOL),
138 CONFIG("multi_read_count", multi_read_count, INT),
139 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
140 CONFIG("lock_pages", lock_pages, BOOL),
141 CONFIG("icmp_rate", icmp_rate, INT),
142 CONFIG("packet_limit", max_packets, INT),
143 CONFIG("cluster_address", cluster_address, IPv4),
144 CONFIG("cluster_interface", cluster_interface, STRING),
145 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
146 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
147 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
148 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
149 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
150 { NULL, 0, 0, 0 },
151 };
152
153 static char *plugin_functions[] = {
154 NULL,
155 "plugin_pre_auth",
156 "plugin_post_auth",
157 "plugin_packet_rx",
158 "plugin_packet_tx",
159 "plugin_timer",
160 "plugin_new_session",
161 "plugin_kill_session",
162 "plugin_control",
163 "plugin_radius_response",
164 "plugin_radius_reset",
165 "plugin_radius_account",
166 "plugin_become_master",
167 "plugin_new_session_master",
168 };
169
170 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
171
172 // Counters for shutdown sessions
173 static sessiont shut_acct[8192];
174 static sessionidt shut_acct_n = 0;
175
176 tunnelt *tunnel = NULL; // Array of tunnel structures.
177 bundlet *bundle = NULL; // Array of bundle structures.
178 fragmentationt *frag = NULL; // Array of fragmentation structures.
179 sessiont *session = NULL; // Array of session structures.
180 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
181 radiust *radius = NULL; // Array of radius structures.
182 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
183 ip_filtert *ip_filters = NULL; // Array of named filters.
184 static controlt *controlfree = 0;
185 struct Tstats *_statistics = NULL;
186 #ifdef RINGBUFFER
187 struct Tringbuffer *ringbuffer = NULL;
188 #endif
189
190 static void cache_ipmap(in_addr_t ip, int s);
191 static void uncache_ipmap(in_addr_t ip);
192 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
193 static void free_ip_address(sessionidt s);
194 static void dump_acct_info(int all);
195 static void sighup_handler(int sig);
196 static void shutdown_handler(int sig);
197 static void sigchild_handler(int sig);
198 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
199 static void update_config(void);
200 static void read_config_file(void);
201 static void initplugins(void);
202 static int add_plugin(char *plugin_name);
203 static int remove_plugin(char *plugin_name);
204 static void plugins_done(void);
205 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
206 static tunnelidt new_tunnel(void);
207 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
208 static void bundleclear(bundleidt b);
209
210 // on slaves, alow BGP to withdraw cleanly before exiting
211 #define QUIT_DELAY 5
212
213 // quit actions (master)
214 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
215 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
216
217 // return internal time (10ths since process startup), set f if given
218 // as a side-effect sets time_now, and time_changed
219 static clockt now(double *f)
220 {
221 struct timeval t;
222 gettimeofday(&t, 0);
223 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
224 if (t.tv_sec != time_now)
225 {
226 time_now = t.tv_sec;
227 time_changed++;
228 }
229 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
230 }
231
232 // work out a retry time based on try number
233 // This is a straight bounded exponential backoff.
234 // Maximum re-try time is 32 seconds. (2^5).
235 clockt backoff(uint8_t try)
236 {
237 if (try > 5) try = 5; // max backoff
238 return now(NULL) + 10 * (1 << try);
239 }
240
241
242 //
243 // Log a debug message. Typically called via the LOG macro
244 //
245 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
246 {
247 static char message[65536] = {0};
248 va_list ap;
249
250 #ifdef RINGBUFFER
251 if (ringbuffer)
252 {
253 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
254 ringbuffer->tail = 0;
255 if (ringbuffer->tail == ringbuffer->head)
256 if (++ringbuffer->head >= RINGBUFFER_SIZE)
257 ringbuffer->head = 0;
258
259 ringbuffer->buffer[ringbuffer->tail].level = level;
260 ringbuffer->buffer[ringbuffer->tail].session = s;
261 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
262 va_start(ap, format);
263 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
264 va_end(ap);
265 }
266 #endif
267
268 if (config->debug < level) return;
269
270 va_start(ap, format);
271 vsnprintf(message, sizeof(message), format, ap);
272
273 if (log_stream)
274 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
275 else if (syslog_log)
276 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
277
278 va_end(ap);
279 }
280
281 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
282 {
283 int i, j;
284 const uint8_t *d = data;
285
286 if (config->debug < level) return;
287
288 // No support for _log_hex to syslog
289 if (log_stream)
290 {
291 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
292 setvbuf(log_stream, NULL, _IOFBF, 16384);
293
294 for (i = 0; i < maxsize; )
295 {
296 fprintf(log_stream, "%4X: ", i);
297 for (j = i; j < maxsize && j < (i + 16); j++)
298 {
299 fprintf(log_stream, "%02X ", d[j]);
300 if (j == i + 7)
301 fputs(": ", log_stream);
302 }
303
304 for (; j < i + 16; j++)
305 {
306 fputs(" ", log_stream);
307 if (j == i + 7)
308 fputs(": ", log_stream);
309 }
310
311 fputs(" ", log_stream);
312 for (j = i; j < maxsize && j < (i + 16); j++)
313 {
314 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
315 fputc(d[j], log_stream);
316 else
317 fputc('.', log_stream);
318
319 if (j == i + 7)
320 fputs(" ", log_stream);
321 }
322
323 i = j;
324 fputs("\n", log_stream);
325 }
326
327 fflush(log_stream);
328 setbuf(log_stream, NULL);
329 }
330 }
331
332 // update a counter, accumulating 2^32 wraps
333 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
334 {
335 uint32_t new = *counter + delta;
336 if (new < *counter)
337 (*wrap)++;
338
339 *counter = new;
340 }
341
342 // initialise the random generator
343 static void initrandom(char *source)
344 {
345 static char path[sizeof(config->random_device)] = "*undefined*";
346
347 // reinitialise only if we are forced to do so or if the config has changed
348 if (source && !strncmp(path, source, sizeof(path)))
349 return;
350
351 // close previous source, if any
352 if (rand_fd >= 0)
353 close(rand_fd);
354
355 rand_fd = -1;
356
357 if (source)
358 {
359 // register changes
360 snprintf(path, sizeof(path), "%s", source);
361
362 if (*path == '/')
363 {
364 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
365 if (rand_fd < 0)
366 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
367 path, strerror(errno));
368 }
369 }
370 }
371
372 // fill buffer with random data
373 void random_data(uint8_t *buf, int len)
374 {
375 int n = 0;
376
377 CSTAT(random_data);
378 if (rand_fd >= 0)
379 {
380 n = read(rand_fd, buf, len);
381 if (n >= len) return;
382 if (n < 0)
383 {
384 if (errno != EAGAIN)
385 {
386 LOG(0, 0, 0, "Error reading from random source: %s\n",
387 strerror(errno));
388
389 // fall back to rand()
390 initrandom(NULL);
391 }
392
393 n = 0;
394 }
395 }
396
397 // append missing data
398 while (n < len)
399 // not using the low order bits from the prng stream
400 buf[n++] = (rand() >> 4) & 0xff;
401 }
402
403 // Add a route
404 //
405 // This adds it to the routing table, advertises it
406 // via BGP if enabled, and stuffs it into the
407 // 'sessionbyip' cache.
408 //
409 // 'ip' and 'mask' must be in _host_ order.
410 //
411 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
412 {
413 struct rtentry r;
414 int i;
415
416 if (!mask) mask = 0xffffffff;
417
418 ip &= mask; // Force the ip to be the first one in the route.
419
420 memset(&r, 0, sizeof(r));
421 r.rt_dev = config->tundevice;
422 r.rt_dst.sa_family = AF_INET;
423 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
424 r.rt_gateway.sa_family = AF_INET;
425 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
426 r.rt_genmask.sa_family = AF_INET;
427 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
428 r.rt_flags = (RTF_UP | RTF_STATIC);
429 if (gw)
430 r.rt_flags |= RTF_GATEWAY;
431 else if (mask == 0xffffffff)
432 r.rt_flags |= RTF_HOST;
433
434 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
435 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
436 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
437
438 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
439 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
440
441 #ifdef BGP
442 if (add)
443 bgp_add_route(htonl(ip), htonl(mask));
444 else
445 bgp_del_route(htonl(ip), htonl(mask));
446 #endif /* BGP */
447
448 // Add/Remove the IPs to the 'sessionbyip' cache.
449 // Note that we add the zero address in the case of
450 // a network route. Roll on CIDR.
451
452 // Note that 's == 0' implies this is the address pool.
453 // We still cache it here, because it will pre-fill
454 // the malloc'ed tree.
455
456 if (s)
457 {
458 if (!add) // Are we deleting a route?
459 s = 0; // Caching the session as '0' is the same as uncaching.
460
461 for (i = ip; (i&mask) == (ip&mask) ; ++i)
462 cache_ipmap(i, s);
463 }
464 }
465
466 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
467 {
468 struct in6_rtmsg rt;
469 char ipv6addr[INET6_ADDRSTRLEN];
470
471 if (ifr6fd < 0)
472 {
473 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
474 return;
475 }
476
477 memset(&rt, 0, sizeof(rt));
478
479 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
480 rt.rtmsg_dst_len = prefixlen;
481 rt.rtmsg_metric = 1;
482 rt.rtmsg_flags = RTF_UP;
483 rt.rtmsg_ifindex = tunidx;
484
485 LOG(1, 0, 0, "Route %s %s/%d\n",
486 add ? "add" : "del",
487 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
488 prefixlen);
489
490 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
491 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
492 strerror(errno));
493
494 // FIXME: need to add BGP routing (RFC2858)
495
496 if (s)
497 {
498 if (!add) // Are we deleting a route?
499 s = 0; // Caching the session as '0' is the same as uncaching.
500
501 cache_ipv6map(ip, prefixlen, s);
502 }
503
504 return;
505 }
506
507 // defined in linux/ipv6.h, but tricky to include from user-space
508 // TODO: move routing to use netlink rather than ioctl
509 struct in6_ifreq {
510 struct in6_addr ifr6_addr;
511 __u32 ifr6_prefixlen;
512 unsigned int ifr6_ifindex;
513 };
514
515 //
516 // Set up TUN interface
517 static void inittun(void)
518 {
519 struct ifreq ifr;
520 struct in6_ifreq ifr6;
521 struct sockaddr_in sin = {0};
522 memset(&ifr, 0, sizeof(ifr));
523 ifr.ifr_flags = IFF_TUN;
524
525 tunfd = open(TUNDEVICE, O_RDWR);
526 if (tunfd < 0)
527 { // fatal
528 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
529 exit(1);
530 }
531 {
532 int flags = fcntl(tunfd, F_GETFL, 0);
533 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
534 }
535 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
536 {
537 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
538 exit(1);
539 }
540 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
541 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
542 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
543
544 sin.sin_family = AF_INET;
545 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
546 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
547
548 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
549 {
550 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
551 exit(1);
552 }
553 /* Bump up the qlen to deal with bursts from the network */
554 ifr.ifr_qlen = 1000;
555 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
556 {
557 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
558 exit(1);
559 }
560 /* set MTU to modem MRU */
561 ifr.ifr_mtu = MRU;
562 if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
563 {
564 LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
565 exit(1);
566 }
567 ifr.ifr_flags = IFF_UP;
568 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
569 {
570 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
571 exit(1);
572 }
573 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
574 {
575 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
576 exit(1);
577 }
578 tunidx = ifr.ifr_ifindex;
579
580 // Only setup IPv6 on the tun device if we have a configured prefix
581 if (config->ipv6_prefix.s6_addr[0]) {
582 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
583
584 // Link local address is FE80::1
585 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
586 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
587 ifr6.ifr6_addr.s6_addr[1] = 0x80;
588 ifr6.ifr6_addr.s6_addr[15] = 1;
589 ifr6.ifr6_prefixlen = 64;
590 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
591 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
592 {
593 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
594 " %s\n", strerror(errno));
595 }
596
597 // Global address is prefix::1
598 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
599 ifr6.ifr6_addr = config->ipv6_prefix;
600 ifr6.ifr6_addr.s6_addr[15] = 1;
601 ifr6.ifr6_prefixlen = 64;
602 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
603 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
604 {
605 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
606 strerror(errno));
607 }
608 }
609 }
610
611 // set up UDP ports
612 static void initudp(void)
613 {
614 int on = 1;
615 struct sockaddr_in addr;
616
617 // Tunnel
618 memset(&addr, 0, sizeof(addr));
619 addr.sin_family = AF_INET;
620 addr.sin_port = htons(L2TPPORT);
621 addr.sin_addr.s_addr = config->bind_address;
622 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
623 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
624 {
625 int flags = fcntl(udpfd, F_GETFL, 0);
626 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
627 }
628 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
629 {
630 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
631 exit(1);
632 }
633
634 // Control
635 memset(&addr, 0, sizeof(addr));
636 addr.sin_family = AF_INET;
637 addr.sin_port = htons(NSCTL_PORT);
638 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
639 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
640 setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
641 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
642 {
643 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
644 exit(1);
645 }
646
647 // Dynamic Authorization Extensions to RADIUS
648 memset(&addr, 0, sizeof(addr));
649 addr.sin_family = AF_INET;
650 addr.sin_port = htons(config->radius_dae_port);
651 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
652 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
653 setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
654 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
655 {
656 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
657 exit(1);
658 }
659
660 // Intercept
661 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
662 }
663
664 //
665 // Find session by IP, < 1 for not found
666 //
667 // Confusingly enough, this 'ip' must be
668 // in _network_ order. This being the common
669 // case when looking it up from IP packet headers.
670 //
671 // We actually use this cache for two things.
672 // #1. For used IP addresses, this maps to the
673 // session ID that it's used by.
674 // #2. For un-used IP addresses, this maps to the
675 // index into the pool table that contains that
676 // IP address.
677 //
678
679 static int lookup_ipmap(in_addr_t ip)
680 {
681 uint8_t *a = (uint8_t *) &ip;
682 uint8_t **d = (uint8_t **) ip_hash;
683
684 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
685 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
686 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
687
688 return (int) (intptr_t) d[(size_t) *a];
689 }
690
691 static int lookup_ipv6map(struct in6_addr ip)
692 {
693 struct ipv6radix *curnode;
694 int i;
695 int s;
696 char ipv6addr[INET6_ADDRSTRLEN];
697
698 curnode = &ipv6_hash[ip.s6_addr[0]];
699 i = 1;
700 s = curnode->sess;
701
702 while (s == 0 && i < 15 && curnode->branch != NULL)
703 {
704 curnode = &curnode->branch[ip.s6_addr[i]];
705 s = curnode->sess;
706 i++;
707 }
708
709 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
710 inet_ntop(AF_INET6, &ip, ipv6addr,
711 INET6_ADDRSTRLEN),
712 s);
713
714 return s;
715 }
716
717 sessionidt sessionbyip(in_addr_t ip)
718 {
719 int s = lookup_ipmap(ip);
720 CSTAT(sessionbyip);
721
722 if (s > 0 && s < MAXSESSION && session[s].opened)
723 return (sessionidt) s;
724
725 return 0;
726 }
727
728 sessionidt sessionbyipv6(struct in6_addr ip)
729 {
730 int s;
731 CSTAT(sessionbyipv6);
732
733 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
734 (ip.s6_addr[0] == 0xFE &&
735 ip.s6_addr[1] == 0x80 &&
736 ip.s6_addr16[1] == 0 &&
737 ip.s6_addr16[2] == 0 &&
738 ip.s6_addr16[3] == 0)) {
739 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
740 } else {
741 s = lookup_ipv6map(ip);
742 }
743
744 if (s > 0 && s < MAXSESSION && session[s].opened)
745 return s;
746
747 return 0;
748 }
749
750 //
751 // Take an IP address in HOST byte order and
752 // add it to the sessionid by IP cache.
753 //
754 // (It's actually cached in network order)
755 //
756 static void cache_ipmap(in_addr_t ip, int s)
757 {
758 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
759 uint8_t *a = (uint8_t *) &nip;
760 uint8_t **d = (uint8_t **) ip_hash;
761 int i;
762
763 for (i = 0; i < 3; i++)
764 {
765 if (!d[(size_t) a[i]])
766 {
767 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
768 return;
769 }
770
771 d = (uint8_t **) d[(size_t) a[i]];
772 }
773
774 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
775
776 if (s > 0)
777 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
778
779 else if (s == 0)
780 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
781 // else a map to an ip pool index.
782 }
783
784 static void uncache_ipmap(in_addr_t ip)
785 {
786 cache_ipmap(ip, 0); // Assign it to the NULL session.
787 }
788
789 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
790 {
791 int i;
792 int bytes;
793 struct ipv6radix *curnode;
794 char ipv6addr[INET6_ADDRSTRLEN];
795
796 curnode = &ipv6_hash[ip.s6_addr[0]];
797
798 bytes = prefixlen >> 3;
799 i = 1;
800 while (i < bytes) {
801 if (curnode->branch == NULL)
802 {
803 if (!(curnode->branch = calloc(256,
804 sizeof (struct ipv6radix))))
805 return;
806 }
807 curnode = &curnode->branch[ip.s6_addr[i]];
808 i++;
809 }
810
811 curnode->sess = s;
812
813 if (s > 0)
814 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
815 inet_ntop(AF_INET6, &ip, ipv6addr,
816 INET6_ADDRSTRLEN),
817 prefixlen);
818 else if (s == 0)
819 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
820 inet_ntop(AF_INET6, &ip, ipv6addr,
821 INET6_ADDRSTRLEN),
822 prefixlen);
823 }
824
825 //
826 // CLI list to dump current ipcache.
827 //
828 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
829 {
830 char **d = (char **) ip_hash, **e, **f, **g;
831 int i, j, k, l;
832 int count = 0;
833
834 if (CLI_HELP_REQUESTED)
835 return CLI_HELP_NO_ARGS;
836
837 cli_print(cli, "%7s %s", "Sess#", "IP Address");
838
839 for (i = 0; i < 256; ++i)
840 {
841 if (!d[i])
842 continue;
843 e = (char **) d[i];
844 for (j = 0; j < 256; ++j)
845 {
846 if (!e[j])
847 continue;
848 f = (char **) e[j];
849 for (k = 0; k < 256; ++k)
850 {
851 if (!f[k])
852 continue;
853 g = (char **)f[k];
854 for (l = 0; l < 256; ++l)
855 {
856 if (!g[l])
857 continue;
858 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
859 ++count;
860 }
861 }
862 }
863 }
864 cli_print(cli, "%d entries in cache", count);
865 return CLI_OK;
866 }
867
868
869 // Find session by username, 0 for not found
870 // walled garden users aren't authenticated, so the username is
871 // reasonably useless. Ignore them to avoid incorrect actions
872 //
873 // This is VERY inefficent. Don't call it often. :)
874 //
875 sessionidt sessionbyuser(char *username)
876 {
877 int s;
878 CSTAT(sessionbyuser);
879
880 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
881 {
882 if (!session[s].opened)
883 continue;
884
885 if (session[s].walled_garden)
886 continue; // Skip walled garden users.
887
888 if (!strncmp(session[s].user, username, 128))
889 return s;
890
891 }
892 return 0; // Not found.
893 }
894
895 void send_garp(in_addr_t ip)
896 {
897 int s;
898 struct ifreq ifr;
899 uint8_t mac[6];
900
901 s = socket(PF_INET, SOCK_DGRAM, 0);
902 if (s < 0)
903 {
904 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
905 return;
906 }
907 memset(&ifr, 0, sizeof(ifr));
908 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
909 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
910 {
911 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
912 close(s);
913 return;
914 }
915 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
916 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
917 {
918 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
919 close(s);
920 return;
921 }
922 close(s);
923 sendarp(ifr.ifr_ifindex, mac, ip);
924 }
925
926 static sessiont *sessiontbysessionidt(sessionidt s)
927 {
928 if (!s || s >= MAXSESSION) return NULL;
929 return &session[s];
930 }
931
932 static sessionidt sessionidtbysessiont(sessiont *s)
933 {
934 sessionidt val = s-session;
935 if (s < session || val >= MAXSESSION) return 0;
936 return val;
937 }
938
939 // actually send a control message for a specific tunnel
940 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
941 {
942 struct sockaddr_in addr;
943
944 CSTAT(tunnelsend);
945
946 if (!t)
947 {
948 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
949 STAT(tunnel_tx_errors);
950 return;
951 }
952
953 if (!tunnel[t].ip)
954 {
955 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
956 STAT(tunnel_tx_errors);
957 return;
958 }
959
960 memset(&addr, 0, sizeof(addr));
961 addr.sin_family = AF_INET;
962 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
963 addr.sin_port = htons(tunnel[t].port);
964
965 // sequence expected, if sequence in message
966 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
967
968 // If this is a control message, deal with retries
969 if (*buf & 0x80)
970 {
971 tunnel[t].last = time_now; // control message sent
972 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
973 if (tunnel[t].try)
974 {
975 STAT(tunnel_retries);
976 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
977 }
978 }
979
980 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
981 {
982 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
983 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
984 STAT(tunnel_tx_errors);
985 return;
986 }
987
988 LOG_HEX(5, "Send Tunnel Data", buf, l);
989 STAT(tunnel_tx_packets);
990 INC_STAT(tunnel_tx_bytes, l);
991 }
992
993 //
994 // Tiny helper function to write data to
995 // the 'tun' device.
996 //
997 int tun_write(uint8_t * data, int size)
998 {
999 return write(tunfd, data, size);
1000 }
1001
1002 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
1003 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
1004 {
1005 int d = (tcp[12] >> 4) * 4;
1006 uint8_t *mss = 0;
1007 uint8_t *opts;
1008 uint8_t *data;
1009 uint16_t orig;
1010 uint32_t sum;
1011
1012 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1013 return;
1014
1015 if (tcp + d > buf + len) // short?
1016 return;
1017
1018 opts = tcp + 20;
1019 data = tcp + d;
1020
1021 while (opts < data)
1022 {
1023 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1024 {
1025 mss = opts + 2;
1026 if (mss + 2 > data) return; // short?
1027 break;
1028 }
1029
1030 if (*opts == 0) return; // end of options
1031 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1032 opts++;
1033 else
1034 opts += opts[1]; // skip over option
1035 }
1036
1037 if (!mss) return; // not found
1038 orig = ntohs(*(uint16_t *) mss);
1039
1040 if (orig <= MSS) return; // mss OK
1041
1042 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1043 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1044 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1045 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1046
1047 // set mss
1048 *(int16_t *) mss = htons(MSS);
1049
1050 // adjust checksum (see rfc1141)
1051 sum = orig + (~MSS & 0xffff);
1052 sum += ntohs(*(uint16_t *) (tcp + 16));
1053 sum = (sum & 0xffff) + (sum >> 16);
1054 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1055 }
1056
1057 void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra)
1058 {
1059 uint16_t proto;
1060 if (extra) {
1061 // Skip the four extra bytes
1062 p += 4;
1063 l -= 4;
1064 }
1065
1066 // Process this frame
1067 if (*p & 1)
1068 {
1069 proto = *p++;
1070 l--;
1071 }
1072 else
1073 {
1074 proto = ntohs(*(uint16_t *) p);
1075 p += 2;
1076 l -= 2;
1077 }
1078
1079 if (proto == PPPIP)
1080 {
1081 if (session[s].die)
1082 {
1083 LOG(4, s, t, "MPPP: Session %u is closing. Don't process PPP packets\n", s);
1084 return; // closing session, PPP not processed
1085 }
1086
1087 session[s].last_packet = session[s].last_data = time_now;
1088 processipin(s, t, p, l);
1089 }
1090 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
1091 {
1092 if (session[s].die)
1093 {
1094 LOG(4, s, t, "MPPP: Session %u is closing. Don't process PPP packets\n", s);
1095 return; // closing session, PPP not processed
1096 }
1097
1098 session[s].last_packet = session[s].last_data = time_now;
1099 processipv6in(s, t, p, l);
1100 }
1101 else
1102 {
1103 LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto);
1104 }
1105 }
1106
1107 // process outgoing (to tunnel) IP
1108 //
1109 static void processipout(uint8_t *buf, int len)
1110 {
1111 sessionidt s;
1112 sessiont *sp;
1113 tunnelidt t;
1114 in_addr_t ip;
1115
1116 uint8_t *data = buf; // Keep a copy of the originals.
1117 int size = len;
1118
1119 uint8_t b1[MAXETHER + 20];
1120 uint8_t b2[MAXETHER + 20];
1121
1122 CSTAT(processipout);
1123
1124 if (len < MIN_IP_SIZE)
1125 {
1126 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1127 STAT(tun_rx_errors);
1128 return;
1129 }
1130 if (len >= MAXETHER)
1131 {
1132 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1133 STAT(tun_rx_errors);
1134 return;
1135 }
1136
1137 // Skip the tun header
1138 buf += 4;
1139 len -= 4;
1140
1141 // Got an IP header now
1142 if (*(uint8_t *)(buf) >> 4 != 4)
1143 {
1144 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1145 return;
1146 }
1147
1148 ip = *(uint32_t *)(buf + 16);
1149 if (!(s = sessionbyip(ip)))
1150 {
1151 // Is this a packet for a session that doesn't exist?
1152 static int rate = 0; // Number of ICMP packets we've sent this second.
1153 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1154
1155 if (last != time_now)
1156 {
1157 last = time_now;
1158 rate = 0;
1159 }
1160
1161 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1162 {
1163 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1164 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1165 config->bind_address ? config->bind_address : my_address, buf, len);
1166 }
1167 return;
1168 }
1169 t = session[s].tunnel;
1170 sp = &session[s];
1171 sp->last_data = time_now;
1172
1173 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1174 if (config->max_packets > 0)
1175 {
1176 if (sess_local[s].last_packet_out == TIME)
1177 {
1178 int max = config->max_packets;
1179
1180 // All packets for throttled sessions are handled by the
1181 // master, so further limit by using the throttle rate.
1182 // A bit of a kludge, since throttle rate is in kbps,
1183 // but should still be generous given our average DSL
1184 // packet size is 200 bytes: a limit of 28kbps equates
1185 // to around 180 packets per second.
1186 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1187 max = sp->throttle_out;
1188
1189 if (++sess_local[s].packets_out > max)
1190 {
1191 sess_local[s].packets_dropped++;
1192 return;
1193 }
1194 }
1195 else
1196 {
1197 if (sess_local[s].packets_dropped)
1198 {
1199 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1200 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1201 sess_local[s].packets_dropped, sess_local[s].packets_out,
1202 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1203 sp->user);
1204 }
1205
1206 sess_local[s].last_packet_out = TIME;
1207 sess_local[s].packets_out = 1;
1208 sess_local[s].packets_dropped = 0;
1209 }
1210 }
1211
1212 // run access-list if any
1213 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1214 return;
1215
1216 // adjust MSS on SYN and SYN,ACK packets with options
1217 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1218 {
1219 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1220 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1221 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1222 }
1223
1224 if (sp->tbf_out)
1225 {
1226 // Are we throttling this session?
1227 if (config->cluster_iam_master)
1228 tbf_queue_packet(sp->tbf_out, data, size);
1229 else
1230 master_throttle_packet(sp->tbf_out, data, size);
1231 return;
1232 }
1233
1234 if (sp->walled_garden && !config->cluster_iam_master)
1235 {
1236 // We are walled-gardening this
1237 master_garden_packet(s, data, size);
1238 return;
1239 }
1240
1241 // Add on L2TP header
1242 {
1243 bundleidt bid = 0;
1244 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1245 {
1246 bid = session[s].bundle;
1247 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1248 LOG(4, s, t, "MPPP: (1)Session number becomes: %u\n", s);
1249 if (len > 256)
1250 {
1251 // Partition the packet to 2 fragments
1252 uint32_t frag1len = len / 2;
1253 uint32_t frag2len = len - frag1len;
1254 uint8_t *p = makeppp(b1, sizeof(b1), buf, frag1len, s, t, PPPIP, 0, bid, MP_BEGIN);
1255 uint8_t *q;
1256
1257 if (!p) return;
1258 tunnelsend(b1, frag1len + (p-b1), t); // send it...
1259 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1260 LOG(4, s, t, "MPPP: (2)Session number becomes: %u\n", s);
1261 q = makeppp(b2, sizeof(b2), buf+frag1len, frag2len, s, t, PPPIP, 0, bid, MP_END);
1262 if (!q) return;
1263 tunnelsend(b2, frag2len + (q-b2), t); // send it...
1264 }
1265 else {
1266 // Send it as one frame
1267 uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS);
1268 if (!p) return;
1269 tunnelsend(b1, len + (p-b1), t); // send it...
1270 }
1271 }
1272 else
1273 {
1274 uint8_t *p = makeppp(b1, sizeof(b1), buf, len, s, t, PPPIP, 0, 0, 0);
1275 if (!p) return;
1276 tunnelsend(b1, len + (p-b1), t); // send it...
1277 }
1278 }
1279
1280 // Snooping this session, send it to intercept box
1281 if (sp->snoop_ip && sp->snoop_port)
1282 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1283
1284 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1285 sp->cout_delta += len;
1286 sp->pout++;
1287 udp_tx += len;
1288
1289 sess_local[s].cout += len; // To send to master..
1290 sess_local[s].pout++;
1291 }
1292
1293 // process outgoing (to tunnel) IPv6
1294 //
1295 static void processipv6out(uint8_t * buf, int len)
1296 {
1297 sessionidt s;
1298 sessiont *sp;
1299 tunnelidt t;
1300 in_addr_t ip;
1301 struct in6_addr ip6;
1302
1303 uint8_t *data = buf; // Keep a copy of the originals.
1304 int size = len;
1305
1306 uint8_t b[MAXETHER + 20];
1307
1308 CSTAT(processipv6out);
1309
1310 if (len < MIN_IP_SIZE)
1311 {
1312 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1313 STAT(tunnel_tx_errors);
1314 return;
1315 }
1316 if (len >= MAXETHER)
1317 {
1318 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1319 STAT(tunnel_tx_errors);
1320 return;
1321 }
1322
1323 // Skip the tun header
1324 buf += 4;
1325 len -= 4;
1326
1327 // Got an IP header now
1328 if (*(uint8_t *)(buf) >> 4 != 6)
1329 {
1330 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1331 return;
1332 }
1333
1334 ip6 = *(struct in6_addr *)(buf+24);
1335 s = sessionbyipv6(ip6);
1336
1337 if (s == 0)
1338 {
1339 ip = *(uint32_t *)(buf + 32);
1340 s = sessionbyip(ip);
1341 }
1342
1343 if (s == 0)
1344 {
1345 // Is this a packet for a session that doesn't exist?
1346 static int rate = 0; // Number of ICMP packets we've sent this second.
1347 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1348
1349 if (last != time_now)
1350 {
1351 last = time_now;
1352 rate = 0;
1353 }
1354
1355 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1356 {
1357 // FIXME: Should send icmp6 host unreachable
1358 }
1359 return;
1360 }
1361 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1362 {
1363 bundleidt bid = session[s].bundle;
1364 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1365 LOG(3, s, session[s].tunnel, "MPPP: Session number becomes: %u\n", s);
1366 }
1367 t = session[s].tunnel;
1368 sp = &session[s];
1369 sp->last_data = time_now;
1370
1371 // FIXME: add DoS prevention/filters?
1372
1373 if (sp->tbf_out)
1374 {
1375 // Are we throttling this session?
1376 if (config->cluster_iam_master)
1377 tbf_queue_packet(sp->tbf_out, data, size);
1378 else
1379 master_throttle_packet(sp->tbf_out, data, size);
1380 return;
1381 }
1382 else if (sp->walled_garden && !config->cluster_iam_master)
1383 {
1384 // We are walled-gardening this
1385 master_garden_packet(s, data, size);
1386 return;
1387 }
1388
1389 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1390
1391 // Add on L2TP header
1392 {
1393 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6, 0, 0, 0);
1394 if (!p) return;
1395 tunnelsend(b, len + (p-b), t); // send it...
1396 }
1397
1398 // Snooping this session, send it to intercept box
1399 if (sp->snoop_ip && sp->snoop_port)
1400 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1401
1402 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1403 sp->cout_delta += len;
1404 sp->pout++;
1405 udp_tx += len;
1406
1407 sess_local[s].cout += len; // To send to master..
1408 sess_local[s].pout++;
1409 }
1410
1411 //
1412 // Helper routine for the TBF filters.
1413 // Used to send queued data in to the user!
1414 //
1415 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1416 {
1417 sessiont *sp;
1418 tunnelidt t;
1419 in_addr_t ip;
1420
1421 uint8_t b[MAXETHER + 20];
1422
1423 if (len < 0 || len > MAXETHER)
1424 {
1425 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1426 return;
1427 }
1428
1429 // Skip the tun header
1430 buf += 4;
1431 len -= 4;
1432
1433 ip = *(in_addr_t *)(buf + 16);
1434
1435 if (!session[s].ip)
1436 return;
1437
1438 t = session[s].tunnel;
1439 sp = &session[s];
1440
1441 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1442
1443 // Add on L2TP header
1444 {
1445 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP, 0, 0, 0);
1446 if (!p) return;
1447 tunnelsend(b, len + (p-b), t); // send it...
1448 }
1449
1450 // Snooping this session.
1451 if (sp->snoop_ip && sp->snoop_port)
1452 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1453
1454 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1455 sp->cout_delta += len;
1456 sp->pout++;
1457 udp_tx += len;
1458
1459 sess_local[s].cout += len; // To send to master..
1460 sess_local[s].pout++;
1461 }
1462
1463 // add an AVP (16 bit)
1464 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1465 {
1466 uint16_t l = (m ? 0x8008 : 0x0008);
1467 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1468 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1469 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1470 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1471 c->length += 8;
1472 }
1473
1474 // add an AVP (32 bit)
1475 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1476 {
1477 uint16_t l = (m ? 0x800A : 0x000A);
1478 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1479 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1480 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1481 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1482 c->length += 10;
1483 }
1484
1485 // add an AVP (string)
1486 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1487 {
1488 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1489 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1490 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1491 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1492 memcpy(c->buf + c->length + 6, val, strlen(val));
1493 c->length += 6 + strlen(val);
1494 }
1495
1496 // add a binary AVP
1497 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1498 {
1499 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1500 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1501 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1502 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1503 memcpy(c->buf + c->length + 6, val, len);
1504 c->length += 6 + len;
1505 }
1506
1507 // new control connection
1508 static controlt *controlnew(uint16_t mtype)
1509 {
1510 controlt *c;
1511 if (!controlfree)
1512 c = malloc(sizeof(controlt));
1513 else
1514 {
1515 c = controlfree;
1516 controlfree = c->next;
1517 }
1518 assert(c);
1519 c->next = 0;
1520 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1521 c->length = 12;
1522 control16(c, 0, mtype, 1);
1523 return c;
1524 }
1525
1526 // send zero block if nothing is waiting
1527 // (ZLB send).
1528 static void controlnull(tunnelidt t)
1529 {
1530 uint8_t buf[12];
1531 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1532 return;
1533
1534 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1535 *(uint16_t *) (buf + 2) = htons(12); // length
1536 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1537 *(uint16_t *) (buf + 6) = htons(0); // session
1538 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1539 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1540 tunnelsend(buf, 12, t);
1541 }
1542
1543 // add a control message to a tunnel, and send if within window
1544 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1545 {
1546 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1547 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1548 *(uint16_t *) (c->buf + 6) = htons(far); // session
1549 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1550 tunnel[t].ns++; // advance sequence
1551 // link in message in to queue
1552 if (tunnel[t].controlc)
1553 tunnel[t].controle->next = c;
1554 else
1555 tunnel[t].controls = c;
1556
1557 tunnel[t].controle = c;
1558 tunnel[t].controlc++;
1559
1560 // send now if space in window
1561 if (tunnel[t].controlc <= tunnel[t].window)
1562 {
1563 tunnel[t].try = 0; // first send
1564 tunnelsend(c->buf, c->length, t);
1565 }
1566 }
1567
1568 //
1569 // Throttle or Unthrottle a session
1570 //
1571 // Throttle the data from/to through a session to no more than
1572 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1573 // user).
1574 //
1575 // If either value is -1, the current value is retained for that
1576 // direction.
1577 //
1578 void throttle_session(sessionidt s, int rate_in, int rate_out)
1579 {
1580 if (!session[s].opened)
1581 return; // No-one home.
1582
1583 if (!*session[s].user)
1584 return; // User not logged in
1585
1586 if (rate_in >= 0)
1587 {
1588 int bytes = rate_in * 1024 / 8; // kbits to bytes
1589 if (session[s].tbf_in)
1590 free_tbf(session[s].tbf_in);
1591
1592 if (rate_in > 0)
1593 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1594 else
1595 session[s].tbf_in = 0;
1596
1597 session[s].throttle_in = rate_in;
1598 }
1599
1600 if (rate_out >= 0)
1601 {
1602 int bytes = rate_out * 1024 / 8;
1603 if (session[s].tbf_out)
1604 free_tbf(session[s].tbf_out);
1605
1606 if (rate_out > 0)
1607 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1608 else
1609 session[s].tbf_out = 0;
1610
1611 session[s].throttle_out = rate_out;
1612 }
1613 }
1614
1615 // add/remove filters from session (-1 = no change)
1616 void filter_session(sessionidt s, int filter_in, int filter_out)
1617 {
1618 if (!session[s].opened)
1619 return; // No-one home.
1620
1621 if (!*session[s].user)
1622 return; // User not logged in
1623
1624 // paranoia
1625 if (filter_in > MAXFILTER) filter_in = -1;
1626 if (filter_out > MAXFILTER) filter_out = -1;
1627 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1628 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1629
1630 if (filter_in >= 0)
1631 {
1632 if (session[s].filter_in)
1633 ip_filters[session[s].filter_in - 1].used--;
1634
1635 if (filter_in > 0)
1636 ip_filters[filter_in - 1].used++;
1637
1638 session[s].filter_in = filter_in;
1639 }
1640
1641 if (filter_out >= 0)
1642 {
1643 if (session[s].filter_out)
1644 ip_filters[session[s].filter_out - 1].used--;
1645
1646 if (filter_out > 0)
1647 ip_filters[filter_out - 1].used++;
1648
1649 session[s].filter_out = filter_out;
1650 }
1651 }
1652
1653 // start tidy shutdown of session
1654 void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause)
1655 {
1656 int walled_garden = session[s].walled_garden;
1657
1658
1659 CSTAT(sessionshutdown);
1660
1661 if (!session[s].opened)
1662 {
1663 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1664 return; // not a live session
1665 }
1666
1667 if (!session[s].die)
1668 {
1669 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1670 LOG(2, s, session[s].tunnel, "Shutting down session %u: %s\n", s, reason);
1671 run_plugins(PLUGIN_KILL_SESSION, &data);
1672 }
1673
1674 if (session[s].ip && !walled_garden && !session[s].die)
1675 {
1676 // RADIUS Stop message
1677 uint16_t r = radiusnew(s);
1678 if (r)
1679 {
1680 // stop, if not already trying
1681 if (radius[r].state != RADIUSSTOP)
1682 {
1683 radius[r].term_cause = term_cause;
1684 radius[r].term_msg = reason;
1685 radiussend(r, RADIUSSTOP);
1686 }
1687 }
1688 else
1689 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1690
1691 // Save counters to dump to accounting file
1692 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1693 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1694 }
1695
1696 if (session[s].ip)
1697 { // IP allocated, clear and unroute
1698 int r;
1699 int routed = 0;
1700 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1701 {
1702 if ((session[s].ip & session[s].route[r].mask) ==
1703 (session[s].route[r].ip & session[s].route[r].mask))
1704 routed++;
1705
1706 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1707 session[s].route[r].ip = 0;
1708 }
1709
1710 if (session[s].ip_pool_index == -1) // static ip
1711 {
1712 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1713 session[s].ip = 0;
1714 }
1715 else
1716 free_ip_address(s);
1717
1718 // unroute IPv6, if setup
1719 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1720 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1721 }
1722
1723 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1724 throttle_session(s, 0, 0);
1725
1726 if (cdn_result)
1727 { // Send CDN
1728 controlt *c = controlnew(14); // sending CDN
1729 if (cdn_error)
1730 {
1731 uint8_t buf[4];
1732 *(uint16_t *) buf = htons(cdn_result);
1733 *(uint16_t *) (buf+2) = htons(cdn_error);
1734 controlb(c, 1, buf, 4, 1);
1735 }
1736 else
1737 control16(c, 1, cdn_result, 1);
1738
1739 control16(c, 14, s, 1); // assigned session (our end)
1740 controladd(c, session[s].far, session[s].tunnel); // send the message
1741 }
1742
1743 if (!session[s].die)
1744 session[s].die = TIME + 150; // Clean up in 15 seconds
1745
1746 // update filter refcounts
1747 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1748 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1749
1750 // clear PPP state
1751 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1752 sess_local[s].lcp.restart = 0;
1753 sess_local[s].ipcp.restart = 0;
1754 sess_local[s].ipv6cp.restart = 0;
1755 sess_local[s].ccp.restart = 0;
1756
1757 cluster_send_session(s);
1758 }
1759
1760 void sendipcp(sessionidt s, tunnelidt t)
1761 {
1762 uint8_t buf[MAXETHER];
1763 uint8_t *q;
1764
1765 CSTAT(sendipcp);
1766 LOG(3, s, t, "IPCP: send ConfigReq\n");
1767
1768 if (!session[s].unique_id)
1769 {
1770 if (!++last_id) ++last_id; // skip zero
1771 session[s].unique_id = last_id;
1772 }
1773
1774 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP, 0, 0, 0);
1775 if (!q) return;
1776
1777 *q = ConfigReq;
1778 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1779 *(uint16_t *) (q + 2) = htons(10); // packet length
1780 q[4] = 3; // ip address option
1781 q[5] = 6; // option length
1782 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1783 config->bind_address ? config->bind_address :
1784 my_address; // send my IP
1785
1786 tunnelsend(buf, 10 + (q - buf), t); // send it
1787 restart_timer(s, ipcp);
1788 }
1789
1790 void sendipv6cp(sessionidt s, tunnelidt t)
1791 {
1792 uint8_t buf[MAXETHER];
1793 uint8_t *q;
1794
1795 CSTAT(sendipv6cp);
1796 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1797
1798 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP, 0, 0, 0);
1799 if (!q) return;
1800
1801 *q = ConfigReq;
1802 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1803 // only send one type
1804 // of request
1805 *(uint16_t *) (q + 2) = htons(14);
1806 q[4] = 1; // interface identifier option
1807 q[5] = 10; // option length
1808 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1809 *(uint32_t *) (q + 10) = 0;
1810 q[13] = 1;
1811
1812 tunnelsend(buf, 14 + (q - buf), t); // send it
1813 restart_timer(s, ipv6cp);
1814 }
1815
1816 static void sessionclear(sessionidt s)
1817 {
1818 memset(&session[s], 0, sizeof(session[s]));
1819 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1820 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1821
1822 session[s].tunnel = T_FREE; // Mark it as free.
1823 session[s].next = sessionfree;
1824 sessionfree = s;
1825 }
1826
1827 // kill a session now
1828 void sessionkill(sessionidt s, char *reason)
1829 {
1830 bundleidt b;
1831
1832 CSTAT(sessionkill);
1833
1834 if (!session[s].opened) // not alive
1835 return;
1836
1837 if (session[s].next)
1838 {
1839 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%u)\n", session[s].next);
1840 return;
1841 }
1842
1843 session[s].die = TIME;
1844 sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
1845 if (sess_local[s].radius)
1846 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1847
1848 LOG(2, s, session[s].tunnel, "Kill session %u (%s): %s\n", s, session[s].user, reason);
1849 if ((b = session[s].bundle))
1850 {
1851 // This session was part of a bundle
1852 bundle[b].num_of_links--;
1853 LOG(3, s, 0, "MPPP: Dropping member link: %u from bundle %u\n", s, b);
1854 if (bundle[b].num_of_links == 0)
1855 {
1856 bundleclear(b);
1857 LOG(3, s, 0, "MPPP: Kill bundle: %u (No remaing member links)\n", b);
1858 }
1859 else
1860 {
1861 // Adjust the members array to accomodate the new change
1862 uint8_t mem_num = 0;
1863 // It should be here num_of_links instead of num_of_links-1 (previous instruction "num_of_links--")
1864 if (bundle[b].members[bundle[b].num_of_links] != s)
1865 {
1866 uint8_t ml;
1867 for (ml = 0; ml<bundle[b].num_of_links; ml++)
1868 {
1869 if (bundle[b].members[ml] == s)
1870 {
1871 mem_num = ml;
1872 break;
1873 }
1874 }
1875 bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
1876 LOG(3, s, 0, "MPPP: Adjusted member links array\n");
1877 }
1878 }
1879 cluster_send_bundle(b);
1880 }
1881 sessionclear(s);
1882 cluster_send_session(s);
1883 }
1884
1885 static void tunnelclear(tunnelidt t)
1886 {
1887 if (!t) return;
1888 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1889 tunnel[t].state = TUNNELFREE;
1890 }
1891
1892 static void bundleclear(bundleidt b)
1893 {
1894 if (!b) return;
1895 memset(&bundle[b], 0, sizeof(bundle[b]));
1896 bundle[b].state = BUNDLEFREE;
1897 }
1898
1899 // kill a tunnel now
1900 static void tunnelkill(tunnelidt t, char *reason)
1901 {
1902 sessionidt s;
1903 controlt *c;
1904
1905 CSTAT(tunnelkill);
1906
1907 tunnel[t].state = TUNNELDIE;
1908
1909 // free control messages
1910 while ((c = tunnel[t].controls))
1911 {
1912 controlt * n = c->next;
1913 tunnel[t].controls = n;
1914 tunnel[t].controlc--;
1915 c->next = controlfree;
1916 controlfree = c;
1917 }
1918 // kill sessions
1919 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1920 if (session[s].tunnel == t)
1921 sessionkill(s, reason);
1922
1923 // free tunnel
1924 tunnelclear(t);
1925 LOG(1, 0, t, "Kill tunnel %u: %s\n", t, reason);
1926 cli_tunnel_actions[t].action = 0;
1927 cluster_send_tunnel(t);
1928 }
1929
1930 // shut down a tunnel cleanly
1931 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1932 {
1933 sessionidt s;
1934
1935 CSTAT(tunnelshutdown);
1936
1937 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1938 {
1939 // never set up, can immediately kill
1940 tunnelkill(t, reason);
1941 return;
1942 }
1943 LOG(1, 0, t, "Shutting down tunnel %u (%s)\n", t, reason);
1944
1945 // close session
1946 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1947 if (session[s].tunnel == t)
1948 sessionshutdown(s, reason, CDN_NONE, TERM_ADMIN_RESET);
1949
1950 tunnel[t].state = TUNNELDIE;
1951 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1952 cluster_send_tunnel(t);
1953 // TBA - should we wait for sessions to stop?
1954 if (result)
1955 {
1956 controlt *c = controlnew(4); // sending StopCCN
1957 if (error)
1958 {
1959 uint8_t buf[64];
1960 int l = 4;
1961 *(uint16_t *) buf = htons(result);
1962 *(uint16_t *) (buf+2) = htons(error);
1963 if (msg)
1964 {
1965 int m = strlen(msg);
1966 if (m + 4 > sizeof(buf))
1967 m = sizeof(buf) - 4;
1968
1969 memcpy(buf+4, msg, m);
1970 l += m;
1971 }
1972
1973 controlb(c, 1, buf, l, 1);
1974 }
1975 else
1976 control16(c, 1, result, 1);
1977
1978 control16(c, 9, t, 1); // assigned tunnel (our end)
1979 controladd(c, 0, t); // send the message
1980 }
1981 }
1982
1983 // read and process packet on tunnel (UDP)
1984 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1985 {
1986 uint8_t *chapresponse = NULL;
1987 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1988 uint8_t *p = buf + 2;
1989
1990
1991 CSTAT(processudp);
1992
1993 udp_rx += len;
1994 udp_rx_pkt++;
1995 LOG_HEX(5, "UDP Data", buf, len);
1996 STAT(tunnel_rx_packets);
1997 INC_STAT(tunnel_rx_bytes, len);
1998 if (len < 6)
1999 {
2000 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
2001 STAT(tunnel_rx_errors);
2002 return;
2003 }
2004 if ((buf[1] & 0x0F) != 2)
2005 {
2006 LOG(1, 0, 0, "Bad L2TP ver %d\n", buf[1] & 0x0F);
2007 STAT(tunnel_rx_errors);
2008 return;
2009 }
2010 if (*buf & 0x40)
2011 { // length
2012 l = ntohs(*(uint16_t *) p);
2013 p += 2;
2014 }
2015 t = ntohs(*(uint16_t *) p);
2016 p += 2;
2017 s = ntohs(*(uint16_t *) p);
2018 p += 2;
2019 if (s >= MAXSESSION)
2020 {
2021 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
2022 STAT(tunnel_rx_errors);
2023 return;
2024 }
2025 if (t >= MAXTUNNEL)
2026 {
2027 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
2028 STAT(tunnel_rx_errors);
2029 return;
2030 }
2031 if (*buf & 0x08)
2032 { // ns/nr
2033 ns = ntohs(*(uint16_t *) p);
2034 p += 2;
2035 nr = ntohs(*(uint16_t *) p);
2036 p += 2;
2037 }
2038 if (*buf & 0x02)
2039 { // offset
2040 uint16_t o = ntohs(*(uint16_t *) p);
2041 p += o + 2;
2042 }
2043 if ((p - buf) > l)
2044 {
2045 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
2046 STAT(tunnel_rx_errors);
2047 return;
2048 }
2049 l -= (p - buf);
2050
2051 // used to time out old tunnels
2052 if (t && tunnel[t].state == TUNNELOPEN)
2053 tunnel[t].lastrec = time_now;
2054
2055 if (*buf & 0x80)
2056 { // control
2057 uint16_t message = 0xFFFF; // message type
2058 uint8_t fatal = 0;
2059 uint8_t mandatory = 0;
2060 uint16_t asession = 0; // assigned session
2061 uint32_t amagic = 0; // magic number
2062 uint8_t aflags = 0; // flags from last LCF
2063 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
2064 char called[MAXTEL] = ""; // called number
2065 char calling[MAXTEL] = ""; // calling number
2066
2067 if (!config->cluster_iam_master)
2068 {
2069 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2070 return;
2071 }
2072
2073 // control messages must have bits 0x80|0x40|0x08
2074 // (type, length and sequence) set, and bits 0x02|0x01
2075 // (offset and priority) clear
2076 if ((*buf & 0xCB) != 0xC8)
2077 {
2078 LOG(1, s, t, "Bad control header %02X\n", *buf);
2079 STAT(tunnel_rx_errors);
2080 return;
2081 }
2082
2083 // check for duplicate tunnel open message
2084 if (!t && ns == 0)
2085 {
2086 int i;
2087
2088 //
2089 // Is this a duplicate of the first packet? (SCCRQ)
2090 //
2091 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
2092 {
2093 if (tunnel[i].state != TUNNELOPENING ||
2094 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
2095 tunnel[i].port != ntohs(addr->sin_port) )
2096 continue;
2097 t = i;
2098 LOG(3, s, t, "Duplicate SCCRQ?\n");
2099 break;
2100 }
2101 }
2102
2103 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %u l-nr %u r-ns %u r-nr %u\n",
2104 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
2105
2106 // if no tunnel specified, assign one
2107 if (!t)
2108 {
2109 if (!(t = new_tunnel()))
2110 {
2111 LOG(1, 0, 0, "No more tunnels\n");
2112 STAT(tunnel_overflow);
2113 return;
2114 }
2115 tunnelclear(t);
2116 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
2117 tunnel[t].port = ntohs(addr->sin_port);
2118 tunnel[t].window = 4; // default window
2119 STAT(tunnel_created);
2120 LOG(1, 0, t, " New tunnel from %s:%u ID %u\n",
2121 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
2122 }
2123
2124 // If the 'ns' just received is not the 'nr' we're
2125 // expecting, just send an ack and drop it.
2126 //
2127 // if 'ns' is less, then we got a retransmitted packet.
2128 // if 'ns' is greater than missed a packet. Either way
2129 // we should ignore it.
2130 if (ns != tunnel[t].nr)
2131 {
2132 // is this the sequence we were expecting?
2133 STAT(tunnel_rx_errors);
2134 LOG(1, 0, t, " Out of sequence tunnel %u, (%u is not the expected %u)\n",
2135 t, ns, tunnel[t].nr);
2136
2137 if (l) // Is this not a ZLB?
2138 controlnull(t);
2139 return;
2140 }
2141
2142 // check sequence of this message
2143 {
2144 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2145 // some to clear maybe?
2146 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2147 {
2148 controlt *c = tunnel[t].controls;
2149 tunnel[t].controls = c->next;
2150 tunnel[t].controlc--;
2151 c->next = controlfree;
2152 controlfree = c;
2153 skip--;
2154 tunnel[t].try = 0; // we have progress
2155 }
2156
2157 // receiver advance (do here so quoted correctly in any sends below)
2158 if (l) tunnel[t].nr = (ns + 1);
2159 if (skip < 0) skip = 0;
2160 if (skip < tunnel[t].controlc)
2161 {
2162 // some control packets can now be sent that were previous stuck out of window
2163 int tosend = tunnel[t].window - skip;
2164 controlt *c = tunnel[t].controls;
2165 while (c && skip)
2166 {
2167 c = c->next;
2168 skip--;
2169 }
2170 while (c && tosend)
2171 {
2172 tunnel[t].try = 0; // first send
2173 tunnelsend(c->buf, c->length, t);
2174 c = c->next;
2175 tosend--;
2176 }
2177 }
2178 if (!tunnel[t].controlc)
2179 tunnel[t].retry = 0; // caught up
2180 }
2181 if (l)
2182 { // if not a null message
2183 int result = 0;
2184 int error = 0;
2185 char *msg = 0;
2186
2187 // Default disconnect cause/message on receipt of CDN. Set to
2188 // more specific value from attribute 1 (result code) or 46
2189 // (disconnect cause) if present below.
2190 int disc_cause_set = 0;
2191 int disc_cause = TERM_NAS_REQUEST;
2192 char const *disc_reason = "Closed (Received CDN).";
2193
2194 // process AVPs
2195 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2196 {
2197 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2198 uint8_t *b = p;
2199 uint8_t flags = *p;
2200 uint16_t mtype;
2201
2202 if (n > l)
2203 {
2204 LOG(1, s, t, "Invalid length in AVP\n");
2205 STAT(tunnel_rx_errors);
2206 return;
2207 }
2208 p += n; // next
2209 l -= n;
2210 if (flags & 0x3C) // reserved bits, should be clear
2211 {
2212 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2213 fatal = flags;
2214 result = 2; // general error
2215 error = 3; // reserved field non-zero
2216 msg = 0;
2217 continue; // next
2218 }
2219 b += 2;
2220 if (*(uint16_t *) (b))
2221 {
2222 LOG(2, s, t, "Unknown AVP vendor %u\n", ntohs(*(uint16_t *) (b)));
2223 fatal = flags;
2224 result = 2; // general error
2225 error = 6; // generic vendor-specific error
2226 msg = "unsupported vendor-specific";
2227 continue; // next
2228 }
2229 b += 2;
2230 mtype = ntohs(*(uint16_t *) (b));
2231 b += 2;
2232 n -= 6;
2233
2234 if (flags & 0x40)
2235 {
2236 uint16_t orig_len;
2237
2238 // handle hidden AVPs
2239 if (!*config->l2tp_secret)
2240 {
2241 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2242 fatal = flags;
2243 result = 2; // general error
2244 error = 6; // generic vendor-specific error
2245 msg = "secret not specified";
2246 continue;
2247 }
2248 if (!session[s].random_vector_length)
2249 {
2250 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2251 fatal = flags;
2252 result = 2; // general error
2253 error = 6; // generic
2254 msg = "no random vector";
2255 continue;
2256 }
2257 if (n < 8)
2258 {
2259 LOG(2, s, t, "Short hidden AVP.\n");
2260 fatal = flags;
2261 result = 2; // general error
2262 error = 2; // length is wrong
2263 msg = 0;
2264 continue;
2265 }
2266
2267 // Unhide the AVP
2268 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2269
2270 orig_len = ntohs(*(uint16_t *) b);
2271 if (orig_len > n + 2)
2272 {
2273 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2274 orig_len, n);
2275
2276 fatal = flags;
2277 result = 2; // general error
2278 error = 2; // length is wrong
2279 msg = 0;
2280 continue;
2281 }
2282
2283 b += 2;
2284 n = orig_len;
2285 }
2286
2287 LOG(4, s, t, " AVP %u (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2288 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2289
2290 switch (mtype)
2291 {
2292 case 0: // message type
2293 message = ntohs(*(uint16_t *) b);
2294 mandatory = flags & 0x80;
2295 LOG(4, s, t, " Message type = %u (%s)\n", *b, l2tp_code(message));
2296 break;
2297 case 1: // result code
2298 {
2299 uint16_t rescode = ntohs(*(uint16_t *) b);
2300 char const *resdesc = "(unknown)";
2301 char const *errdesc = NULL;
2302 int cause = 0;
2303
2304 if (message == 4)
2305 { /* StopCCN */
2306 resdesc = l2tp_stopccn_result_code(rescode);
2307 cause = TERM_LOST_SERVICE;
2308 }
2309 else if (message == 14)
2310 { /* CDN */
2311 resdesc = l2tp_cdn_result_code(rescode);
2312 if (rescode == 1)
2313 cause = TERM_LOST_CARRIER;
2314 else
2315 cause = TERM_ADMIN_RESET;
2316 }
2317
2318 LOG(4, s, t, " Result Code %u: %s\n", rescode, resdesc);
2319 if (n >= 4)
2320 {
2321 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2322 errdesc = l2tp_error_code(errcode);
2323 LOG(4, s, t, " Error Code %u: %s\n", errcode, errdesc);
2324 }
2325 if (n > 4)
2326 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2327
2328 if (cause && disc_cause_set < mtype) // take cause from attrib 46 in preference
2329 {
2330 disc_cause_set = mtype;
2331 disc_reason = errdesc ? errdesc : resdesc;
2332 disc_cause = cause;
2333 }
2334
2335 break;
2336 }
2337 break;
2338 case 2: // protocol version
2339 {
2340 version = ntohs(*(uint16_t *) (b));
2341 LOG(4, s, t, " Protocol version = %u\n", version);
2342 if (version && version != 0x0100)
2343 { // allow 0.0 and 1.0
2344 LOG(1, s, t, " Bad protocol version %04X\n", version);
2345 fatal = flags;
2346 result = 5; // unspported protocol version
2347 error = 0x0100; // supported version
2348 msg = 0;
2349 continue; // next
2350 }
2351 }
2352 break;
2353 case 3: // framing capabilities
2354 break;
2355 case 4: // bearer capabilities
2356 break;
2357 case 5: // tie breaker
2358 // We never open tunnels, so we don't care about tie breakers
2359 continue;
2360 case 6: // firmware revision
2361 break;
2362 case 7: // host name
2363 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2364 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2365 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2366 // TBA - to send to RADIUS
2367 break;
2368 case 8: // vendor name
2369 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2370 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2371 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2372 break;
2373 case 9: // assigned tunnel
2374 tunnel[t].far = ntohs(*(uint16_t *) (b));
2375 LOG(4, s, t, " Remote tunnel id = %u\n", tunnel[t].far);
2376 break;
2377 case 10: // rx window
2378 tunnel[t].window = ntohs(*(uint16_t *) (b));
2379 if (!tunnel[t].window)
2380 tunnel[t].window = 1; // window of 0 is silly
2381 LOG(4, s, t, " rx window = %u\n", tunnel[t].window);
2382 break;
2383 case 11: // Challenge
2384 {
2385 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2386 build_chap_response(b, 2, n, &chapresponse);
2387 }
2388 break;
2389 case 13: // Response
2390 // Why did they send a response? We never challenge.
2391 LOG(2, s, t, " received unexpected challenge response\n");
2392 break;
2393
2394 case 14: // assigned session
2395 asession = session[s].far = ntohs(*(uint16_t *) (b));
2396 LOG(4, s, t, " assigned session = %u\n", asession);
2397 break;
2398 case 15: // call serial number
2399 LOG(4, s, t, " call serial number = %u\n", ntohl(*(uint32_t *)b));
2400 break;
2401 case 18: // bearer type
2402 LOG(4, s, t, " bearer type = %u\n", ntohl(*(uint32_t *)b));
2403 // TBA - for RADIUS
2404 break;
2405 case 19: // framing type
2406 LOG(4, s, t, " framing type = %u\n", ntohl(*(uint32_t *)b));
2407 // TBA
2408 break;
2409 case 21: // called number
2410 memset(called, 0, sizeof(called));
2411 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2412 LOG(4, s, t, " Called <%s>\n", called);
2413 break;
2414 case 22: // calling number
2415 memset(calling, 0, sizeof(calling));
2416 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2417 LOG(4, s, t, " Calling <%s>\n", calling);
2418 break;
2419 case 23: // subtype
2420 break;
2421 case 24: // tx connect speed
2422 if (n == 4)
2423 {
2424 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2425 }
2426 else
2427 {
2428 // AS5300s send connect speed as a string
2429 char tmp[30];
2430 memset(tmp, 0, sizeof(tmp));
2431 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2432 session[s].tx_connect_speed = atol(tmp);
2433 }
2434 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2435 break;
2436 case 38: // rx connect speed
2437 if (n == 4)
2438 {
2439 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2440 }
2441 else
2442 {
2443 // AS5300s send connect speed as a string
2444 char tmp[30];
2445 memset(tmp, 0, sizeof(tmp));
2446 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2447 session[s].rx_connect_speed = atol(tmp);
2448 }
2449 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2450 break;
2451 case 25: // Physical Channel ID
2452 {
2453 uint32_t tmp = ntohl(*(uint32_t *) b);
2454 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2455 break;
2456 }
2457 case 29: // Proxy Authentication Type
2458 {
2459 uint16_t atype = ntohs(*(uint16_t *)b);
2460 LOG(4, s, t, " Proxy Auth Type %u (%s)\n", atype, ppp_auth_type(atype));
2461 break;
2462 }
2463 case 30: // Proxy Authentication Name
2464 {
2465 char authname[64];
2466 memset(authname, 0, sizeof(authname));
2467 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2468 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2469 authname);
2470 break;
2471 }
2472 case 31: // Proxy Authentication Challenge
2473 {
2474 LOG(4, s, t, " Proxy Auth Challenge\n");
2475 break;
2476 }
2477 case 32: // Proxy Authentication ID
2478 {
2479 uint16_t authid = ntohs(*(uint16_t *)(b));
2480 LOG(4, s, t, " Proxy Auth ID (%u)\n", authid);
2481 break;
2482 }
2483 case 33: // Proxy Authentication Response
2484 LOG(4, s, t, " Proxy Auth Response\n");
2485 break;
2486 case 27: // last sent lcp
2487 { // find magic number
2488 uint8_t *p = b, *e = p + n;
2489 while (p + 1 < e && p[1] && p + p[1] <= e)
2490 {
2491 if (*p == 5 && p[1] == 6) // Magic-Number
2492 amagic = ntohl(*(uint32_t *) (p + 2));
2493 else if (*p == 7) // Protocol-Field-Compression
2494 aflags |= SESSION_PFC;
2495 else if (*p == 8) // Address-and-Control-Field-Compression
2496 aflags |= SESSION_ACFC;
2497 p += p[1];
2498 }
2499 }
2500 break;
2501 case 28: // last recv lcp confreq
2502 break;
2503 case 26: // Initial Received LCP CONFREQ
2504 break;
2505 case 39: // seq required - we control it as an LNS anyway...
2506 break;
2507 case 36: // Random Vector
2508 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2509 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2510 if (n > sizeof(session[s].random_vector))
2511 n = sizeof(session[s].random_vector);
2512 memcpy(session[s].random_vector, b, n);
2513 session[s].random_vector_length = n;
2514 break;
2515 case 46: // ppp disconnect cause
2516 if (n >= 5)
2517 {
2518 uint16_t code = ntohs(*(uint16_t *) b);
2519 uint16_t proto = ntohs(*(uint16_t *) (b + 2));
2520 uint8_t dir = *(b + 4);
2521
2522 LOG(4, s, t, " PPP disconnect cause "
2523 "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
2524 code, proto, dir, n - 5, b + 5);
2525
2526 disc_cause_set = mtype;
2527
2528 switch (code)
2529 {
2530 case 1: // admin disconnect
2531 disc_cause = TERM_ADMIN_RESET;
2532 disc_reason = "Administrative disconnect";
2533 break;
2534 case 3: // lcp terminate
2535 if (dir != 2) break; // 1=peer (LNS), 2=local (LAC)
2536 disc_cause = TERM_USER_REQUEST;
2537 disc_reason = "Normal disconnection";
2538 break;
2539 case 4: // compulsory encryption unavailable
2540 if (dir != 1) break; // 1=refused by peer, 2=local
2541 disc_cause = TERM_USER_ERROR;
2542 disc_reason = "Compulsory encryption refused";
2543 break;
2544 case 5: // lcp: fsm timeout
2545 disc_cause = TERM_PORT_ERROR;
2546 disc_reason = "LCP: FSM timeout";
2547 break;
2548 case 6: // lcp: no recognisable lcp packets received
2549 disc_cause = TERM_PORT_ERROR;
2550 disc_reason = "LCP: no recognisable LCP packets";
2551 break;
2552 case 7: // lcp: magic-no error (possibly looped back)
2553 disc_cause = TERM_PORT_ERROR;
2554 disc_reason = "LCP: magic-no error (possible loop)";
2555 break;
2556 case 8: // lcp: echo request timeout
2557 disc_cause = TERM_PORT_ERROR;
2558 disc_reason = "LCP: echo request timeout";
2559 break;
2560 case 13: // auth: fsm timeout
2561 disc_cause = TERM_SERVICE_UNAVAILABLE;
2562 disc_reason = "Authentication: FSM timeout";
2563 break;
2564 case 15: // auth: unacceptable auth protocol
2565 disc_cause = TERM_SERVICE_UNAVAILABLE;
2566 disc_reason = "Unacceptable authentication protocol";
2567 break;
2568 case 16: // auth: authentication failed
2569 disc_cause = TERM_SERVICE_UNAVAILABLE;
2570 disc_reason = "Authentication failed";
2571 break;
2572 case 17: // ncp: fsm timeout
2573 disc_cause = TERM_SERVICE_UNAVAILABLE;
2574 disc_reason = "NCP: FSM timeout";
2575 break;
2576 case 18: // ncp: no ncps available
2577 disc_cause = TERM_SERVICE_UNAVAILABLE;
2578 disc_reason = "NCP: no NCPs available";
2579 break;
2580 case 19: // ncp: failure to converge on acceptable address
2581 disc_cause = TERM_SERVICE_UNAVAILABLE;
2582 disc_reason = (dir == 1)
2583 ? "NCP: too many Configure-Naks received from peer"
2584 : "NCP: too many Configure-Naks sent to peer";
2585 break;
2586 case 20: // ncp: user not permitted to use any address
2587 disc_cause = TERM_SERVICE_UNAVAILABLE;
2588 disc_reason = (dir == 1)
2589 ? "NCP: local link address not acceptable to peer"
2590 : "NCP: remote link address not acceptable";
2591 break;
2592 }
2593 }
2594 break;
2595 default:
2596 {
2597 static char e[] = "unknown AVP 0xXXXX";
2598 LOG(2, s, t, " Unknown AVP type %u\n", mtype);
2599 fatal = flags;
2600 result = 2; // general error
2601 error = 8; // unknown mandatory AVP
2602 sprintf((msg = e) + 14, "%04x", mtype);
2603 continue; // next
2604 }
2605 }
2606 }
2607 // process message
2608 if (fatal & 0x80)
2609 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2610 else
2611 switch (message)
2612 {
2613 case 1: // SCCRQ - Start Control Connection Request
2614 tunnel[t].state = TUNNELOPENING;
2615 if (main_quit != QUIT_SHUTDOWN)
2616 {
2617 controlt *c = controlnew(2); // sending SCCRP
2618 control16(c, 2, version, 1); // protocol version
2619 control32(c, 3, 3, 1); // framing
2620 controls(c, 7, hostname, 1); // host name
2621 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2622 control16(c, 9, t, 1); // assigned tunnel
2623 controladd(c, 0, t); // send the resply
2624 }
2625 else
2626 {
2627 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2628 }
2629 break;
2630 case 2: // SCCRP
2631 tunnel[t].state = TUNNELOPEN;
2632 break;
2633 case 3: // SCCN
2634 tunnel[t].state = TUNNELOPEN;
2635 controlnull(t); // ack
2636 break;
2637 case 4: // StopCCN
2638 controlnull(t); // ack
2639 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2640 break;
2641 case 6: // HELLO
2642 controlnull(t); // simply ACK
2643 break;
2644 case 7: // OCRQ
2645 // TBA
2646 break;
2647 case 8: // OCRO
2648 // TBA
2649 break;
2650 case 9: // OCCN
2651 // TBA
2652 break;
2653 case 10: // ICRQ
2654 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2655 {
2656 controlt *c = controlnew(11); // ICRP
2657
2658 s = sessionfree;
2659 sessionfree = session[s].next;
2660 memset(&session[s], 0, sizeof(session[s]));
2661
2662 if (s > config->cluster_highest_sessionid)
2663 config->cluster_highest_sessionid = s;
2664
2665 session[s].opened = time_now;
2666 session[s].tunnel = t;
2667 session[s].far = asession;
2668 session[s].last_packet = session[s].last_data = time_now;
2669 LOG(3, s, t, "New session (%u/%u)\n", tunnel[t].far, session[s].far);
2670 control16(c, 14, s, 1); // assigned session
2671 controladd(c, asession, t); // send the reply
2672
2673 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2674 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2675
2676 session[s].ppp.phase = Establish;
2677 session[s].ppp.lcp = Starting;
2678
2679 STAT(session_created);
2680 break;
2681 }
2682
2683 {
2684 controlt *c = controlnew(14); // CDN
2685 if (!sessionfree)
2686 {
2687 STAT(session_overflow);
2688 LOG(1, 0, t, "No free sessions\n");
2689 control16(c, 1, 4, 0); // temporary lack of resources
2690 }
2691 else
2692 control16(c, 1, 2, 7); // shutting down, try another
2693
2694 controladd(c, asession, t); // send the message
2695 }
2696 return;
2697 case 11: // ICRP
2698 // TBA
2699 break;
2700 case 12: // ICCN
2701 if (amagic == 0) amagic = time_now;
2702 session[s].magic = amagic; // set magic number
2703 session[s].flags = aflags; // set flags received
2704 session[s].mru = PPPoE_MRU; // default
2705 controlnull(t); // ack
2706
2707 // start LCP
2708 sess_local[s].lcp_authtype = config->radius_authprefer;
2709 sess_local[s].ppp_mru = MRU;
2710
2711 // Set multilink options before sending initial LCP packet
2712 sess_local[s].mp_mrru = 1614;
2713 sess_local[s].mp_epdis = config->bind_address ? config->bind_address : my_address;
2714
2715 sendlcp(s, t);
2716 change_state(s, lcp, RequestSent);
2717 break;
2718
2719 case 14: // CDN
2720 controlnull(t); // ack
2721 sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
2722 break;
2723 case 0xFFFF:
2724 LOG(1, s, t, "Missing message type\n");
2725 break;
2726 default:
2727 STAT(tunnel_rx_errors);
2728 if (mandatory)
2729 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2730 else
2731 LOG(1, s, t, "Unknown message type %u\n", message);
2732 break;
2733 }
2734 if (chapresponse) free(chapresponse);
2735 cluster_send_tunnel(t);
2736 }
2737 else
2738 {
2739 LOG(4, s, t, " Got a ZLB ack\n");
2740 }
2741 }
2742 else
2743 { // data
2744 uint16_t proto;
2745
2746 LOG_HEX(5, "Receive Tunnel Data", p, l);
2747 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2748 { // HDLC address header, discard
2749 p += 2;
2750 l -= 2;
2751 }
2752 if (l < 2)
2753 {
2754 LOG(1, s, t, "Short ppp length %d\n", l);
2755 STAT(tunnel_rx_errors);
2756 return;
2757 }
2758 if (*p & 1)
2759 {
2760 proto = *p++;
2761 l--;
2762 }
2763 else
2764 {
2765 proto = ntohs(*(uint16_t *) p);
2766 p += 2;
2767 l -= 2;
2768 }
2769
2770 if (s && !session[s].opened) // Is something wrong??
2771 {
2772 if (!config->cluster_iam_master)
2773 {
2774 // Pass it off to the master to deal with..
2775 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2776 return;
2777 }
2778
2779
2780 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2781 STAT(tunnel_rx_errors);
2782 return;
2783 }
2784
2785 if (proto == PPPPAP)
2786 {
2787 session[s].last_packet = time_now;
2788 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2789 processpap(s, t, p, l);
2790 }
2791 else if (proto == PPPCHAP)
2792 {
2793 session[s].last_packet = time_now;
2794 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2795 processchap(s, t, p, l);
2796 }
2797 else if (proto == PPPLCP)
2798 {
2799 session[s].last_packet = time_now;
2800 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2801 processlcp(s, t, p, l);
2802 }
2803 else if (proto == PPPIPCP)
2804 {
2805 session[s].last_packet = time_now;
2806 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2807 processipcp(s, t, p, l);
2808 }
2809 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2810 {
2811 session[s].last_packet = time_now;
2812 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2813 processipv6cp(s, t, p, l);
2814 }
2815 else if (proto == PPPCCP)
2816 {
2817 session[s].last_packet = time_now;
2818 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2819 processccp(s, t, p, l);
2820 }
2821 else if (proto == PPPIP)
2822 {
2823 if (session[s].die)
2824 {
2825 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2826 return; // closing session, PPP not processed
2827 }
2828
2829 session[s].last_packet = session[s].last_data = time_now;
2830 if (session[s].walled_garden && !config->cluster_iam_master)
2831 {
2832 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2833 return;
2834 }
2835
2836 processipin(s, t, p, l);
2837 }
2838 else if (proto == PPPMP)
2839 {
2840 if (session[s].die)
2841 {
2842 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2843 return; // closing session, PPP not processed
2844 }
2845
2846 session[s].last_packet = session[s].last_data = time_now;
2847 if (session[s].walled_garden && !config->cluster_iam_master)
2848 {
2849 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2850 return;
2851 }
2852
2853 processmpin(s, t, p, l);
2854 }
2855 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2856 {
2857 if (session[s].die)
2858 {
2859 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2860 return; // closing session, PPP not processed
2861 }
2862
2863 session[s].last_packet = session[s].last_data = time_now;
2864 if (session[s].walled_garden && !config->cluster_iam_master)
2865 {
2866 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2867 return;
2868 }
2869
2870 processipv6in(s, t, p, l);
2871 }
2872 else if (session[s].ppp.lcp == Opened)
2873 {
2874 session[s].last_packet = time_now;
2875 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2876 protoreject(s, t, p, l, proto);
2877 }
2878 else
2879 {
2880 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2881 proto, ppp_state(session[s].ppp.lcp));
2882 }
2883 }
2884 }
2885
2886 // read and process packet on tun
2887 static void processtun(uint8_t * buf, int len)
2888 {
2889 LOG_HEX(5, "Receive TUN Data", buf, len);
2890 STAT(tun_rx_packets);
2891 INC_STAT(tun_rx_bytes, len);
2892
2893 CSTAT(processtun);
2894
2895 eth_rx_pkt++;
2896 eth_rx += len;
2897 if (len < 22)
2898 {
2899 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2900 STAT(tun_rx_errors);
2901 return;
2902 }
2903
2904 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2905 processipout(buf, len);
2906 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2907 && config->ipv6_prefix.s6_addr[0])
2908 processipv6out(buf, len);
2909
2910 // Else discard.
2911 }
2912
2913 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2914 // that we look at the whole of the tunnel, radius and session tables
2915 // every second
2916 static void regular_cleanups(double period)
2917 {
2918 // Next tunnel, radius and session to check for actions on.
2919 static tunnelidt t = 0;
2920 static int r = 0;
2921 static sessionidt s = 0;
2922
2923 int t_actions = 0;
2924 int r_actions = 0;
2925 int s_actions = 0;
2926
2927 int t_slice;
2928 int r_slice;
2929 int s_slice;
2930
2931 int i;
2932 int a;
2933
2934 // divide up tables into slices based on the last run
2935 t_slice = config->cluster_highest_tunnelid * period;
2936 r_slice = (MAXRADIUS - 1) * period;
2937 s_slice = config->cluster_highest_sessionid * period;
2938
2939 if (t_slice < 1)
2940 t_slice = 1;
2941 else if (t_slice > config->cluster_highest_tunnelid)
2942 t_slice = config->cluster_highest_tunnelid;
2943
2944 if (r_slice < 1)
2945 r_slice = 1;
2946 else if (r_slice > (MAXRADIUS - 1))
2947 r_slice = MAXRADIUS - 1;
2948
2949 if (s_slice < 1)
2950 s_slice = 1;
2951 else if (s_slice > config->cluster_highest_sessionid)
2952 s_slice = config->cluster_highest_sessionid;
2953
2954 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2955
2956 for (i = 0; i < t_slice; i++)
2957 {
2958 t++;
2959 if (t > config->cluster_highest_tunnelid)
2960 t = 1;
2961
2962 // check for expired tunnels
2963 if (tunnel[t].die && tunnel[t].die <= TIME)
2964 {
2965 STAT(tunnel_timeout);
2966 tunnelkill(t, "Expired");
2967 t_actions++;
2968 continue;
2969 }
2970 // check for message resend
2971 if (tunnel[t].retry && tunnel[t].controlc)
2972 {
2973 // resend pending messages as timeout on reply
2974 if (tunnel[t].retry <= TIME)
2975 {
2976 controlt *c = tunnel[t].controls;
2977 uint8_t w = tunnel[t].window;
2978 tunnel[t].try++; // another try
2979 if (tunnel[t].try > 5)
2980 tunnelkill(t, "Timeout on control message"); // game over
2981 else
2982 while (c && w--)
2983 {
2984 tunnelsend(c->buf, c->length, t);
2985 c = c->next;
2986 }
2987
2988 t_actions++;
2989 }
2990 }
2991 // Send hello
2992 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
2993 {
2994 controlt *c = controlnew(6); // sending HELLO
2995 controladd(c, 0, t); // send the message
2996 LOG(3, 0, t, "Sending HELLO message\n");
2997 t_actions++;
2998 }
2999
3000 // Check for tunnel changes requested from the CLI
3001 if ((a = cli_tunnel_actions[t].action))
3002 {
3003 cli_tunnel_actions[t].action = 0;
3004 if (a & CLI_TUN_KILL)
3005 {
3006 LOG(2, 0, t, "Dropping tunnel by CLI\n");
3007 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
3008 t_actions++;
3009 }
3010 }
3011 }
3012
3013 for (i = 0; i < r_slice; i++)
3014 {
3015 r++;
3016 if (r >= MAXRADIUS)
3017 r = 1;
3018
3019 if (!radius[r].state)
3020 continue;
3021
3022 if (radius[r].retry <= TIME)
3023 {
3024 radiusretry(r);
3025 r_actions++;
3026 }
3027 }
3028
3029 for (i = 0; i < s_slice; i++)
3030 {
3031 s++;
3032 if (s > config->cluster_highest_sessionid)
3033 s = 1;
3034
3035 if (!session[s].opened) // Session isn't in use
3036 continue;
3037
3038 // check for expired sessions
3039 if (session[s].die)
3040 {
3041 if (session[s].die <= TIME)
3042 {
3043 sessionkill(s, "Expired");
3044 s_actions++;
3045 }
3046 continue;
3047 }
3048
3049 // check for timed out sessions
3050 if (session[s].timeout)
3051 {
3052 bundleidt bid = session[s].bundle;
3053 if (bid)
3054 {
3055 clockt curr_time = time_now;
3056 if (curr_time - bundle[bid].last_check >= 1)
3057 {
3058 bundle[bid].online_time += (curr_time-bundle[bid].last_check)*bundle[bid].num_of_links;
3059 bundle[bid].last_check = curr_time;
3060 if (bundle[bid].online_time >= session[s].timeout)
3061 {
3062 int ses;
3063 for (ses = bundle[bid].num_of_links - 1; ses >= 0; ses--)
3064 {
3065 sessionshutdown(bundle[bid].members[ses], "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3066 s_actions++;
3067 continue;
3068 }
3069 }
3070 }
3071 }
3072 else if (session[s].timeout <= time_now - session[s].opened)
3073 {
3074 sessionshutdown(s, "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3075 s_actions++;
3076 continue;
3077 }
3078 }
3079
3080 // PPP timeouts
3081 if (sess_local[s].lcp.restart <= time_now)
3082 {
3083 int next_state = session[s].ppp.lcp;
3084 switch (session[s].ppp.lcp)
3085 {
3086 case RequestSent:
3087 case AckReceived:
3088 next_state = RequestSent;
3089
3090 case AckSent:
3091 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
3092 {
3093 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
3094 sendlcp(s, session[s].tunnel);
3095 change_state(s, lcp, next_state);
3096 }
3097 else
3098 {
3099 sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3100 STAT(session_timeout);
3101 }
3102
3103 s_actions++;
3104 }
3105
3106 if (session[s].die)
3107 continue;
3108 }
3109
3110 if (sess_local[s].ipcp.restart <= time_now)
3111 {
3112 int next_state = session[s].ppp.ipcp;
3113 switch (session[s].ppp.ipcp)
3114 {
3115 case RequestSent:
3116 case AckReceived:
3117 next_state = RequestSent;
3118
3119 case AckSent:
3120 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
3121 {
3122 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
3123 sendipcp(s, session[s].tunnel);
3124 change_state(s, ipcp, next_state);
3125 }
3126 else
3127 {
3128 sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3129 STAT(session_timeout);
3130 }
3131
3132 s_actions++;
3133 }
3134
3135 if (session[s].die)
3136 continue;
3137 }
3138
3139 if (sess_local[s].ipv6cp.restart <= time_now)
3140 {
3141 int next_state = session[s].ppp.ipv6cp;
3142 switch (session[s].ppp.ipv6cp)
3143 {
3144 case RequestSent:
3145 case AckReceived:
3146 next_state = RequestSent;
3147
3148 case AckSent:
3149 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
3150 {
3151 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
3152 sendipv6cp(s, session[s].tunnel);
3153 change_state(s, ipv6cp, next_state);
3154 }
3155 else
3156 {
3157 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
3158 change_state(s, ipv6cp, Stopped);
3159 }
3160
3161 s_actions++;
3162 }
3163 }
3164
3165 if (sess_local[s].ccp.restart <= time_now)
3166 {
3167 int next_state = session[s].ppp.ccp;
3168 switch (session[s].ppp.ccp)
3169 {
3170 case RequestSent:
3171 case AckReceived:
3172 next_state = RequestSent;
3173
3174 case AckSent:
3175 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
3176 {
3177 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
3178 sendccp(s, session[s].tunnel);
3179 change_state(s, ccp, next_state);
3180 }
3181 else
3182 {
3183 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
3184 change_state(s, ccp, Stopped);
3185 }
3186
3187 s_actions++;
3188 }
3189 }
3190
3191 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
3192 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
3193 {
3194 sessionshutdown(s, "No response to LCP ECHO requests.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3195 STAT(session_timeout);
3196 s_actions++;
3197 continue;
3198 }
3199
3200 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
3201 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
3202 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
3203 {
3204 uint8_t b[MAXETHER];
3205
3206 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP, 1, 0, 0);
3207 if (!q) continue;
3208
3209 *q = EchoReq;
3210 *(uint8_t *)(q + 1) = (time_now % 255); // ID
3211 *(uint16_t *)(q + 2) = htons(8); // Length
3212 *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
3213
3214 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
3215 (int)(time_now - session[s].last_packet));
3216 tunnelsend(b, 24, session[s].tunnel); // send it
3217 sess_local[s].last_echo = time_now;
3218 s_actions++;
3219 }
3220
3221 // Drop sessions who have reached session_timeout seconds
3222 if (session[s].session_timeout && (time_now - session[s].opened >= session[s].session_timeout))
3223 {
3224 sessionshutdown(s, "Session Timeout Reached", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3225 STAT(session_timeout);
3226 s_actions++;
3227 continue;
3228 }
3229
3230 // Drop sessions who have reached idle_timeout seconds
3231 if (session[s].last_data && session[s].idle_timeout && (time_now - session[s].last_data >= session[s].idle_timeout))
3232 {
3233 sessionshutdown(s, "Idle Timeout Reached", CDN_ADMIN_DISC, TERM_IDLE_TIMEOUT);
3234 STAT(session_timeout);
3235 s_actions++;
3236 continue;
3237 }
3238
3239 // Check for actions requested from the CLI
3240 if ((a = cli_session_actions[s].action))
3241 {
3242 int send = 0;
3243
3244 cli_session_actions[s].action = 0;
3245 if (a & CLI_SESS_KILL)
3246 {
3247 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
3248 sessionshutdown(s, "Requested by administrator.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
3249 a = 0; // dead, no need to check for other actions
3250 s_actions++;
3251 }
3252
3253 if (a & CLI_SESS_NOSNOOP)
3254 {
3255 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
3256 session[s].snoop_ip = 0;
3257 session[s].snoop_port = 0;
3258 s_actions++;
3259 send++;
3260 }
3261 else if (a & CLI_SESS_SNOOP)
3262 {
3263 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%u)\n",
3264 fmtaddr(cli_session_actions[s].snoop_ip, 0),
3265 cli_session_actions[s].snoop_port);
3266
3267 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
3268 session[s].snoop_port = cli_session_actions[s].snoop_port;
3269 s_actions++;
3270 send++;
3271 }
3272
3273 if (a & CLI_SESS_NOTHROTTLE)
3274 {
3275 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
3276 throttle_session(s, 0, 0);
3277 s_actions++;
3278 send++;
3279 }
3280 else if (a & CLI_SESS_THROTTLE)
3281 {
3282 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
3283 cli_session_actions[s].throttle_in,
3284 cli_session_actions[s].throttle_out);
3285
3286 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
3287 s_actions++;
3288 send++;
3289 }
3290
3291 if (a & CLI_SESS_NOFILTER)
3292 {
3293 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3294 filter_session(s, 0, 0);
3295 s_actions++;
3296 send++;
3297 }
3298 else if (a & CLI_SESS_FILTER)
3299 {
3300 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3301 cli_session_actions[s].filter_in,
3302 cli_session_actions[s].filter_out);
3303
3304 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3305 s_actions++;
3306 send++;
3307 }
3308
3309 if (send)
3310 cluster_send_session(s);
3311 }
3312
3313 // RADIUS interim accounting
3314 if (config->radius_accounting && config->radius_interim > 0
3315 && session[s].ip && !session[s].walled_garden
3316 && !sess_local[s].radius // RADIUS already in progress
3317 && time_now - sess_local[s].last_interim >= config->radius_interim)
3318 {
3319 int rad = radiusnew(s);
3320 if (!rad)
3321 {
3322 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3323 STAT(radius_overflow);
3324 continue;
3325 }
3326
3327 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3328 session[s].user, session[s].unique_id);
3329
3330 radiussend(rad, RADIUSINTERIM);
3331 sess_local[s].last_interim = time_now;
3332 s_actions++;
3333 }
3334 }
3335
3336 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3337 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3338 }
3339
3340 //
3341 // Are we in the middle of a tunnel update, or radius
3342 // requests??
3343 //
3344 static int still_busy(void)
3345 {
3346 int i;
3347 static clockt last_talked = 0;
3348 static clockt start_busy_wait = 0;
3349
3350 if (!config->cluster_iam_master)
3351 {
3352 #ifdef BGP
3353 static time_t stopped_bgp = 0;
3354 if (bgp_configured)
3355 {
3356 if (!stopped_bgp)
3357 {
3358 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3359
3360 for (i = 0; i < BGP_NUM_PEERS; i++)
3361 if (bgp_peers[i].state == Established)
3362 bgp_stop(&bgp_peers[i]);
3363
3364 stopped_bgp = time_now;
3365
3366 // we don't want to become master
3367 cluster_send_ping(0);
3368
3369 return 1;
3370 }
3371
3372 if (time_now < (stopped_bgp + QUIT_DELAY))
3373 return 1;
3374 }
3375 #endif /* BGP */
3376
3377 return 0;
3378 }
3379
3380 if (main_quit == QUIT_SHUTDOWN)
3381 {
3382 static int dropped = 0;
3383 if (!dropped)
3384 {
3385 int i;
3386
3387 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3388 for (i = 1; i < MAXTUNNEL; i++)
3389 if (tunnel[i].ip || tunnel[i].state)
3390 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3391
3392 dropped = 1;
3393 }
3394 }
3395
3396 if (start_busy_wait == 0)
3397 start_busy_wait = TIME;
3398
3399 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3400 {
3401 if (!tunnel[i].controlc)
3402 continue;
3403
3404 if (last_talked != TIME)
3405 {
3406 LOG(2, 0, 0, "Tunnel %u still has un-acked control messages.\n", i);
3407 last_talked = TIME;
3408 }
3409 return 1;
3410 }
3411
3412 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3413 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3414 {
3415 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3416 return 0;
3417 }
3418
3419 for (i = 1; i < MAXRADIUS; i++)
3420 {
3421 if (radius[i].state == RADIUSNULL)
3422 continue;
3423 if (radius[i].state == RADIUSWAIT)
3424 continue;
3425
3426 if (last_talked != TIME)
3427 {
3428 LOG(2, 0, 0, "Radius session %u is still busy (sid %u)\n", i, radius[i].session);
3429 last_talked = TIME;
3430 }
3431 return 1;
3432 }
3433
3434 return 0;
3435 }
3436
3437 #ifdef HAVE_EPOLL
3438 # include <sys/epoll.h>
3439 #else
3440 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3441 # include "fake_epoll.h"
3442 #endif
3443
3444 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3445 #define BASE_FDS 6
3446
3447 // additional polled fds
3448 #ifdef BGP
3449 # define EXTRA_FDS BGP_NUM_PEERS
3450 #else
3451 # define EXTRA_FDS 0
3452 #endif
3453
3454 // main loop - gets packets on tun or udp and processes them
3455 static void mainloop(void)
3456 {
3457 int i;
3458 uint8_t buf[65536];
3459 clockt next_cluster_ping = 0; // send initial ping immediately
3460 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3461 int maxevent = sizeof(events)/sizeof(*events);
3462
3463 if ((epollfd = epoll_create(maxevent)) < 0)
3464 {
3465 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3466 exit(1);
3467 }
3468
3469 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3470 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3471
3472 /* setup our fds to poll for input */
3473 {
3474 static struct event_data d[BASE_FDS];
3475 struct epoll_event e;
3476
3477 e.events = EPOLLIN;
3478 i = 0;
3479
3480 if (clifd >= 0)
3481 {
3482 d[i].type = FD_TYPE_CLI;
3483 e.data.ptr = &d[i++];
3484 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3485 }
3486
3487 d[i].type = FD_TYPE_CLUSTER;
3488 e.data.ptr = &d[i++];
3489 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3490
3491 d[i].type = FD_TYPE_TUN;
3492 e.data.ptr = &d[i++];
3493 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3494
3495 d[i].type = FD_TYPE_UDP;
3496 e.data.ptr = &d[i++];
3497 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3498
3499 d[i].type = FD_TYPE_CONTROL;
3500 e.data.ptr = &d[i++];
3501 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3502
3503 d[i].type = FD_TYPE_DAE;
3504 e.data.ptr = &d[i++];
3505 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3506 }
3507
3508 #ifdef BGP
3509 signal(SIGPIPE, SIG_IGN);
3510 bgp_setup(config->as_number);
3511 if (config->bind_address)
3512 bgp_add_route(config->bind_address, 0xffffffff);
3513
3514 for (i = 0; i < BGP_NUM_PEERS; i++)
3515 {
3516 if (config->neighbour[i].name[0])
3517 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3518 config->neighbour[i].as, config->neighbour[i].keepalive,
3519 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3520 }
3521 #endif /* BGP */
3522
3523 while (!main_quit || still_busy())
3524 {
3525 int more = 0;
3526 int n;
3527
3528
3529 if (main_reload)
3530 {
3531 main_reload = 0;
3532 read_config_file();
3533 config->reload_config++;
3534 }
3535
3536 if (config->reload_config)
3537 {
3538 config->reload_config = 0;
3539 update_config();
3540 }
3541
3542 #ifdef BGP
3543 bgp_set_poll();
3544 #endif /* BGP */
3545
3546 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3547 STAT(select_called);
3548
3549 TIME = now(NULL);
3550 if (n < 0)
3551 {
3552 if (errno == EINTR ||
3553 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3554 continue;
3555
3556 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3557 break; // exit
3558 }
3559
3560 if (n)
3561 {
3562 struct sockaddr_in addr;
3563 struct in_addr local;
3564 socklen_t alen;
3565 int c, s;
3566 int udp_ready = 0;
3567 int tun_ready = 0;
3568 int cluster_ready = 0;
3569 int udp_pkts = 0;
3570 int tun_pkts = 0;
3571 int cluster_pkts = 0;
3572 #ifdef BGP
3573 uint32_t bgp_events[BGP_NUM_PEERS];
3574 memset(bgp_events, 0, sizeof(bgp_events));
3575 #endif /* BGP */
3576
3577 for (c = n, i = 0; i < c; i++)
3578 {
3579 struct event_data *d = events[i].data.ptr;
3580
3581 switch (d->type)
3582 {
3583 case FD_TYPE_CLI: // CLI connections
3584 {
3585 int cli;
3586
3587 alen = sizeof(addr);
3588 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3589 {
3590 cli_do(cli);
3591 close(cli);
3592 }
3593 else
3594 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3595
3596 n--;
3597 break;
3598 }
3599
3600 // these are handled below, with multiple interleaved reads
3601 case FD_TYPE_CLUSTER: cluster_ready++; break;
3602 case FD_TYPE_TUN: tun_ready++; break;
3603 case FD_TYPE_UDP: udp_ready++; break;
3604
3605 case FD_TYPE_CONTROL: // nsctl commands
3606 alen = sizeof(addr);
3607 s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3608 if (s > 0) processcontrol(buf, s, &addr, alen, &local);
3609 n--;
3610 break;
3611
3612 case FD_TYPE_DAE: // DAE requests
3613 alen = sizeof(addr);
3614 s = recvfromto(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3615 if (s > 0) processdae(buf, s, &addr, alen, &local);
3616 n--;
3617 break;
3618
3619 case FD_TYPE_RADIUS: // RADIUS response
3620 alen = sizeof(addr);
3621 s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
3622 if (s >= 0 && config->cluster_iam_master)
3623 {
3624 if (addr.sin_addr.s_addr == config->radiusserver[0] ||
3625 addr.sin_addr.s_addr == config->radiusserver[1])
3626 processrad(buf, s, d->index);
3627 else
3628 LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
3629 fmtaddr(addr.sin_addr.s_addr, 0));
3630 }
3631
3632 n--;
3633 break;
3634
3635 #ifdef BGP
3636 case FD_TYPE_BGP:
3637 bgp_events[d->index] = events[i].events;
3638 n--;
3639 break;
3640 #endif /* BGP */
3641
3642 default:
3643 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3644 }
3645 }
3646
3647 #ifdef BGP
3648 bgp_process(bgp_events);
3649 #endif /* BGP */
3650
3651 for (c = 0; n && c < config->multi_read_count; c++)
3652 {
3653 // L2TP
3654 if (udp_ready)
3655 {
3656 alen = sizeof(addr);
3657 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3658 {
3659 processudp(buf, s, &addr);
3660 udp_pkts++;
3661 }
3662 else
3663 {
3664 udp_ready = 0;
3665 n--;
3666 }
3667 }
3668
3669 // incoming IP
3670 if (tun_ready)
3671 {
3672 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3673 {
3674 processtun(buf, s);
3675 tun_pkts++;
3676 }
3677 else
3678 {
3679 tun_ready = 0;
3680 n--;
3681 }
3682 }
3683
3684 // cluster
3685 if (cluster_ready)
3686 {
3687 alen = sizeof(addr);
3688 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3689 {
3690 processcluster(buf, s, addr.sin_addr.s_addr);
3691 cluster_pkts++;
3692 }
3693 else
3694 {
3695 cluster_ready = 0;
3696 n--;
3697 }
3698 }
3699 }
3700
3701 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3702 STAT(multi_read_used);
3703
3704 if (c >= config->multi_read_count)
3705 {
3706 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3707 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3708
3709 STAT(multi_read_exceeded);
3710 more++;
3711 }
3712 }
3713
3714 if (time_changed)
3715 {
3716 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
3717
3718 // Log current traffic stats
3719 snprintf(config->bandwidth, sizeof(config->bandwidth),
3720 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3721 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
3722 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
3723 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
3724
3725 udp_tx = udp_rx = 0;
3726 udp_rx_pkt = eth_rx_pkt = 0;
3727 eth_tx = eth_rx = 0;
3728 time_changed = 0;
3729
3730 if (config->dump_speed)
3731 printf("%s\n", config->bandwidth);
3732
3733 // Update the internal time counter
3734 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3735
3736 {
3737 // Run timer hooks
3738 struct param_timer p = { time_now };
3739 run_plugins(PLUGIN_TIMER, &p);
3740 }
3741 }
3742
3743 // Runs on every machine (master and slaves).
3744 if (next_cluster_ping <= TIME)
3745 {
3746 // Check to see which of the cluster is still alive..
3747
3748 cluster_send_ping(basetime); // Only does anything if we're a slave
3749 cluster_check_master(); // ditto.
3750
3751 cluster_heartbeat(); // Only does anything if we're a master.
3752 cluster_check_slaves(); // ditto.
3753
3754 master_update_counts(); // If we're a slave, send our byte counters to our master.
3755
3756 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3757 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3758 else
3759 next_cluster_ping = TIME + config->cluster_hb_interval;
3760 }
3761
3762 if (!config->cluster_iam_master)
3763 continue;
3764
3765 // Run token bucket filtering queue..
3766 // Only run it every 1/10th of a second.
3767 {
3768 static clockt last_run = 0;
3769 if (last_run != TIME)
3770 {
3771 last_run = TIME;
3772 tbf_run_timer();
3773 }
3774 }
3775
3776 // Handle timeouts, retries etc.
3777 {
3778 static double last_clean = 0;
3779 double this_clean;
3780 double diff;
3781
3782 TIME = now(&this_clean);
3783 diff = this_clean - last_clean;
3784
3785 // Run during idle time (after we've handled
3786 // all incoming packets) or every 1/10th sec
3787 if (!more || diff > 0.1)
3788 {
3789 regular_cleanups(diff);
3790 last_clean = this_clean;
3791 }
3792 }
3793
3794 if (*config->accounting_dir)
3795 {
3796 static clockt next_acct = 0;
3797 static clockt next_shut_acct = 0;
3798
3799 if (next_acct <= TIME)
3800 {
3801 // Dump accounting data
3802 next_acct = TIME + ACCT_TIME;
3803 next_shut_acct = TIME + ACCT_SHUT_TIME;
3804 dump_acct_info(1);
3805 }
3806 else if (next_shut_acct <= TIME)
3807 {
3808 // Dump accounting data for shutdown sessions
3809 next_shut_acct = TIME + ACCT_SHUT_TIME;
3810 if (shut_acct_n)
3811 dump_acct_info(0);
3812 }
3813 }
3814 }
3815
3816 // Are we the master and shutting down??
3817 if (config->cluster_iam_master)
3818 cluster_heartbeat(); // Flush any queued changes..
3819
3820 // Ok. Notify everyone we're shutting down. If we're
3821 // the master, this will force an election.
3822 cluster_send_ping(0);
3823
3824 //
3825 // Important!!! We MUST not process any packets past this point!
3826 LOG(1, 0, 0, "Shutdown complete\n");
3827 }
3828
3829 static void stripdomain(char *host)
3830 {
3831 char *p;
3832
3833 if ((p = strchr(host, '.')))
3834 {
3835 char *domain = 0;
3836 char _domain[1024];
3837
3838 // strip off domain
3839 FILE *resolv = fopen("/etc/resolv.conf", "r");
3840 if (resolv)
3841 {
3842 char buf[1024];
3843 char *b;
3844
3845 while (fgets(buf, sizeof(buf), resolv))
3846 {
3847 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3848 continue;
3849
3850 if (!isspace(buf[6]))
3851 continue;
3852
3853 b = buf + 7;
3854 while (isspace(*b)) b++;
3855
3856 if (*b)
3857 {
3858 char *d = b;
3859 while (*b && !isspace(*b)) b++;
3860 *b = 0;
3861 if (buf[0] == 'd') // domain is canonical
3862 {
3863 domain = d;
3864 break;
3865 }
3866
3867 // first search line
3868 if (!domain)
3869 {
3870 // hold, may be subsequent domain line
3871 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3872 domain = _domain;
3873 }
3874 }
3875 }
3876
3877 fclose(resolv);
3878 }
3879
3880 if (domain)
3881 {
3882 int hl = strlen(host);
3883 int dl = strlen(domain);
3884 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3885 host[hl -dl - 1] = 0;
3886 }
3887 else
3888 {
3889 *p = 0; // everything after first dot
3890 }
3891 }
3892 }
3893
3894 // Init data structures
3895 static void initdata(int optdebug, char *optconfig)
3896 {
3897 int i;
3898
3899 if (!(config = shared_malloc(sizeof(configt))))
3900 {
3901 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3902 exit(1);
3903 }
3904
3905 memset(config, 0, sizeof(configt));
3906 time(&config->start_time);
3907 strncpy(config->config_file, optconfig, strlen(optconfig));
3908 config->debug = optdebug;
3909 config->num_tbfs = MAXTBFS;
3910 config->rl_rate = 28; // 28kbps
3911 config->cluster_mcast_ttl = 1;
3912 config->cluster_master_min_adv = 1;
3913 config->ppp_restart_time = 3;
3914 config->ppp_max_configure = 10;
3915 config->ppp_max_failure = 5;
3916 strcpy(config->random_device, RANDOMDEVICE);
3917
3918 log_stream = stderr;
3919
3920 #ifdef RINGBUFFER
3921 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3922 {
3923 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3924 exit(1);
3925 }
3926 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3927 #endif
3928
3929 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3930 {
3931 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3932 exit(1);
3933 }
3934 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3935 {
3936 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3937 exit(1);
3938 }
3939 if (!(bundle = shared_malloc(sizeof(bundlet) * MAXBUNDLE)))
3940 {
3941 LOG(0, 0, 0, "Error doing malloc for bundles: %s\n", strerror(errno));
3942 exit(1);
3943 }
3944 if (!(frag = shared_malloc(sizeof(fragmentationt) * MAXBUNDLE)))
3945 {
3946 LOG(0, 0, 0, "Error doing malloc for fragmentations: %s\n", strerror(errno));
3947 exit(1);
3948 }
3949 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3950 {
3951 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3952 exit(1);
3953 }
3954
3955 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3956 {
3957 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3958 exit(1);
3959 }
3960
3961 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3962 {
3963 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3964 exit(1);
3965 }
3966
3967 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3968 {
3969 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3970 exit(1);
3971 }
3972
3973 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3974 {
3975 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3976 exit(1);
3977 }
3978 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3979
3980 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3981 {
3982 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3983 exit(1);
3984 }
3985 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3986
3987 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3988 {
3989 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3990 exit(1);
3991 }
3992 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3993
3994 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3995 memset(bundle, 0, sizeof(bundlet) * MAXBUNDLE);
3996 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3997 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3998 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3999
4000 // Put all the sessions on the free list marked as undefined.
4001 for (i = 1; i < MAXSESSION; i++)
4002 {
4003 session[i].next = i + 1;
4004 session[i].tunnel = T_UNDEF; // mark it as not filled in.
4005 }
4006 session[MAXSESSION - 1].next = 0;
4007 sessionfree = 1;
4008
4009 // Mark all the tunnels as undefined (waiting to be filled in by a download).
4010 for (i = 1; i < MAXTUNNEL; i++)
4011 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
4012
4013 for (i = 1; i < MAXBUNDLE; i++) {
4014 bundle[i].state = BUNDLEUNDEF;
4015 }
4016
4017 if (!*hostname)
4018 {
4019 // Grab my hostname unless it's been specified
4020 gethostname(hostname, sizeof(hostname));
4021 stripdomain(hostname);
4022 }
4023
4024 _statistics->start_time = _statistics->last_reset = time(NULL);
4025
4026 #ifdef BGP
4027 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
4028 {
4029 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
4030 exit(1);
4031 }
4032 #endif /* BGP */
4033 }
4034
4035 static int assign_ip_address(sessionidt s)
4036 {
4037 uint32_t i;
4038 int best = -1;
4039 time_t best_time = time_now;
4040 char *u = session[s].user;
4041 char reuse = 0;
4042
4043
4044 CSTAT(assign_ip_address);
4045
4046 for (i = 1; i < ip_pool_size; i++)
4047 {
4048 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
4049 continue;
4050
4051 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
4052 {
4053 best = i;
4054 reuse = 1;
4055 break;
4056 }
4057
4058 if (ip_address_pool[i].last < best_time)
4059 {
4060 best = i;
4061 if (!(best_time = ip_address_pool[i].last))
4062 break; // never used, grab this one
4063 }
4064 }
4065
4066 if (best < 0)
4067 {
4068 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
4069 return 0;
4070 }
4071
4072 session[s].ip = ip_address_pool[best].address;
4073 session[s].ip_pool_index = best;
4074 ip_address_pool[best].assigned = 1;
4075 ip_address_pool[best].last = time_now;
4076 ip_address_pool[best].session = s;
4077 if (session[s].walled_garden)
4078 /* Don't track addresses of users in walled garden (note: this
4079 means that their address isn't "sticky" even if they get
4080 un-gardened). */
4081 ip_address_pool[best].user[0] = 0;
4082 else
4083 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
4084
4085 STAT(ip_allocated);
4086 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
4087 reuse ? "Reusing" : "Allocating", best);
4088
4089 return 1;
4090 }
4091
4092 static void free_ip_address(sessionidt s)
4093 {
4094 int i = session[s].ip_pool_index;
4095
4096
4097 CSTAT(free_ip_address);
4098
4099 if (!session[s].ip)
4100 return; // what the?
4101
4102 if (i < 0) // Is this actually part of the ip pool?
4103 i = 0;
4104
4105 STAT(ip_freed);
4106 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
4107 session[s].ip = 0;
4108 ip_address_pool[i].assigned = 0;
4109 ip_address_pool[i].session = 0;
4110 ip_address_pool[i].last = time_now;
4111 }
4112
4113 //
4114 // Fsck the address pool against the session table.
4115 // Normally only called when we become a master.
4116 //
4117 // This isn't perfect: We aren't keep tracking of which
4118 // users used to have an IP address.
4119 //
4120 void rebuild_address_pool(void)
4121 {
4122 int i;
4123
4124 //
4125 // Zero the IP pool allocation, and build
4126 // a map from IP address to pool index.
4127 for (i = 1; i < MAXIPPOOL; ++i)
4128 {
4129 ip_address_pool[i].assigned = 0;
4130 ip_address_pool[i].session = 0;
4131 if (!ip_address_pool[i].address)
4132 continue;
4133
4134 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
4135 }
4136
4137 for (i = 0; i < MAXSESSION; ++i)
4138 {
4139 int ipid;
4140 if (!(session[i].opened && session[i].ip))
4141 continue;
4142
4143 ipid = - lookup_ipmap(htonl(session[i].ip));
4144
4145 if (session[i].ip_pool_index < 0)
4146 {
4147 // Not allocated out of the pool.
4148 if (ipid < 1) // Not found in the pool either? good.
4149 continue;
4150
4151 LOG(0, i, 0, "Session %u has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
4152 i, fmtaddr(session[i].ip, 0), ipid);
4153
4154 // Fall through and process it as part of the pool.
4155 }
4156
4157
4158 if (ipid > MAXIPPOOL || ipid < 0)
4159 {
4160 LOG(0, i, 0, "Session %u has a pool IP that's not found in the pool! (%d)\n", i, ipid);
4161 ipid = -1;
4162 session[i].ip_pool_index = ipid;
4163 continue;
4164 }
4165
4166 ip_address_pool[ipid].assigned = 1;
4167 ip_address_pool[ipid].session = i;
4168 ip_address_pool[ipid].last = time_now;
4169 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
4170 session[i].ip_pool_index = ipid;
4171 cache_ipmap(session[i].ip, i); // Fix the ip map.
4172 }
4173 }
4174
4175 //
4176 // Fix the address pool to match a changed session.
4177 // (usually when the master sends us an update).
4178 static void fix_address_pool(int sid)
4179 {
4180 int ipid;
4181
4182 ipid = session[sid].ip_pool_index;
4183
4184 if (ipid > ip_pool_size)
4185 return; // Ignore it. rebuild_address_pool will fix it up.
4186
4187 if (ip_address_pool[ipid].address != session[sid].ip)
4188 return; // Just ignore it. rebuild_address_pool will take care of it.
4189
4190 ip_address_pool[ipid].assigned = 1;
4191 ip_address_pool[ipid].session = sid;
4192 ip_address_pool[ipid].last = time_now;
4193 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
4194 }
4195
4196 //
4197 // Add a block of addresses to the IP pool to hand out.
4198 //
4199 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
4200 {
4201 int i;
4202 if (mask == 0)
4203 mask = 0xffffffff; // Host route only.
4204
4205 addr &= mask;
4206
4207 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
4208 return ;
4209
4210 for (i = addr ;(i & mask) == addr; ++i)
4211 {
4212 if ((i & 0xff) == 0 || (i&0xff) == 255)
4213 continue; // Skip 0 and broadcast addresses.
4214
4215 ip_address_pool[ip_pool_size].address = i;
4216 ip_address_pool[ip_pool_size].assigned = 0;
4217 ++ip_pool_size;
4218 if (ip_pool_size >= MAXIPPOOL)
4219 {
4220 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
4221 return;
4222 }
4223 }
4224 }
4225
4226 // Initialize the IP address pool
4227 static void initippool()
4228 {
4229 FILE *f;
4230 char *p;
4231 char buf[4096];
4232 memset(ip_address_pool, 0, sizeof(ip_address_pool));
4233
4234 if (!(f = fopen(IPPOOLFILE, "r")))
4235 {
4236 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
4237 exit(1);
4238 }
4239
4240 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
4241 {
4242 char *pool = buf;
4243 buf[4095] = 0; // Force it to be zero terminated/
4244
4245 if (*buf == '#' || *buf == '\n')
4246 continue; // Skip comments / blank lines
4247 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
4248 if ((p = (char *)strchr(buf, ':')))
4249 {
4250 in_addr_t src;
4251 *p = '\0';
4252 src = inet_addr(buf);
4253 if (src == INADDR_NONE)
4254 {
4255 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
4256 exit(1);
4257 }
4258 // This entry is for a specific IP only
4259 if (src != config->bind_address)
4260 continue;
4261 *p = ':';
4262 pool = p+1;
4263 }
4264 if ((p = (char *)strchr(pool, '/')))
4265 {
4266 // It's a range
4267 int numbits = 0;
4268 in_addr_t start = 0, mask = 0;
4269
4270 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
4271 *p++ = 0;
4272 if (!*p || !(numbits = atoi(p)))
4273 {
4274 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
4275 continue;
4276 }
4277 start = ntohl(inet_addr(pool));
4278 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
4279
4280 // Add a static route for this pool
4281 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
4282 fmtaddr(htonl(start), 0), 32 + mask);
4283
4284 routeset(0, start, mask, 0, 1);
4285
4286 add_to_ip_pool(start, mask);
4287 }
4288 else
4289 {
4290 // It's a single ip address
4291 add_to_ip_pool(ntohl(inet_addr(pool)), 0);
4292 }
4293 }
4294 fclose(f);
4295 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
4296 }
4297
4298 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
4299 {
4300 struct sockaddr_in snoop_addr = {0};
4301 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
4302 return;
4303
4304 snoop_addr.sin_family = AF_INET;
4305 snoop_addr.sin_addr.s_addr = destination;
4306 snoop_addr.sin_port = ntohs(port);
4307
4308 LOG(5, 0, 0, "Snooping %d byte packet to %s:%u\n", size,
4309 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
4310 htons(snoop_addr.sin_port));
4311
4312 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
4313 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
4314
4315 STAT(packets_snooped);
4316 }
4317
4318 static int dump_session(FILE **f, sessiont *s)
4319 {
4320 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
4321 return 1;
4322
4323 if (!*f)
4324 {
4325 char filename[1024];
4326 char timestr[64];
4327 time_t now = time(NULL);
4328
4329 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4330 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4331
4332 if (!(*f = fopen(filename, "w")))
4333 {
4334 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4335 return 0;
4336 }
4337
4338 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4339 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4340 "# host: %s\n"
4341 "# endpoint: %s\n"
4342 "# time: %ld\n"
4343 "# uptime: %ld\n"
4344 "# format: username ip qos uptxoctets downrxoctets\n",
4345 hostname,
4346 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
4347 now,
4348 now - basetime);
4349 }
4350
4351 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4352 fprintf(*f, "%s %s %d %u %u\n",
4353 s->user, // username
4354 fmtaddr(htonl(s->ip), 0), // ip
4355 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4356 (uint32_t) s->cin_delta, // uptxoctets
4357 (uint32_t) s->cout_delta); // downrxoctets
4358
4359 s->cin_delta = s->cout_delta = 0;
4360
4361 return 1;
4362 }
4363
4364 static void dump_acct_info(int all)
4365 {
4366 int i;
4367 FILE *f = NULL;
4368
4369
4370 CSTAT(dump_acct_info);
4371
4372 if (shut_acct_n)
4373 {
4374 for (i = 0; i < shut_acct_n; i++)
4375 dump_session(&f, &shut_acct[i]);
4376
4377 shut_acct_n = 0;
4378 }
4379
4380 if (all)
4381 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4382 dump_session(&f, &session[i]);
4383
4384 if (f)
4385 fclose(f);
4386 }
4387
4388 // Main program
4389 int main(int argc, char *argv[])
4390 {
4391 int i;
4392 int optdebug = 0;
4393 char *optconfig = CONFIGFILE;
4394
4395 time(&basetime); // start clock
4396
4397 // scan args
4398 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4399 {
4400 switch (i)
4401 {
4402 case 'd':
4403 if (fork()) exit(0);
4404 setsid();
4405 freopen("/dev/null", "r", stdin);
4406 freopen("/dev/null", "w", stdout);
4407 freopen("/dev/null", "w", stderr);
4408 break;
4409 case 'v':
4410 optdebug++;
4411 break;
4412 case 'c':
4413 optconfig = optarg;
4414 break;
4415 case 'h':
4416 snprintf(hostname, sizeof(hostname), "%s", optarg);
4417 break;
4418 default:
4419 printf("Args are:\n"
4420 "\t-d\t\tDetach from terminal\n"
4421 "\t-c <file>\tConfig file\n"
4422 "\t-h <hostname>\tForce hostname\n"
4423 "\t-v\t\tDebug\n");
4424
4425 return (0);
4426 break;
4427 }
4428 }
4429
4430 // Start the timer routine off
4431 time(&time_now);
4432 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4433
4434 initplugins();
4435 initdata(optdebug, optconfig);
4436
4437 init_cli(hostname);
4438 read_config_file();
4439 update_config();
4440 init_tbf(config->num_tbfs);
4441
4442 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4443 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005, 2006 Optus Internet Engineering\n");
4444 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4445 {
4446 struct rlimit rlim;
4447 rlim.rlim_cur = RLIM_INFINITY;
4448 rlim.rlim_max = RLIM_INFINITY;
4449 // Remove the maximum core size
4450 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4451 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4452
4453 // Make core dumps go to /tmp
4454 chdir("/tmp");
4455 }
4456
4457 if (config->scheduler_fifo)
4458 {
4459 int ret;
4460 struct sched_param params = {0};
4461 params.sched_priority = 1;
4462
4463 if (get_nprocs() < 2)
4464 {
4465 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4466 config->scheduler_fifo = 0;
4467 }
4468 else
4469 {
4470 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4471 {
4472 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4473 }
4474 else
4475 {
4476 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4477 config->scheduler_fifo = 0;
4478 }
4479 }
4480 }
4481
4482 /* Set up the cluster communications port. */
4483 if (cluster_init() < 0)
4484 exit(1);
4485
4486 inittun();
4487 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4488
4489 initudp();
4490 initrad();
4491 initippool();
4492
4493 // seed prng
4494 {
4495 unsigned seed = time_now ^ getpid();
4496 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4497 srand(seed);
4498 }
4499
4500 signal(SIGHUP, sighup_handler);
4501 signal(SIGCHLD, sigchild_handler);
4502 signal(SIGTERM, shutdown_handler);
4503 signal(SIGINT, shutdown_handler);
4504 signal(SIGQUIT, shutdown_handler);
4505
4506 // Prevent us from getting paged out
4507 if (config->lock_pages)
4508 {
4509 if (!mlockall(MCL_CURRENT))
4510 LOG(1, 0, 0, "Locking pages into memory\n");
4511 else
4512 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4513 }
4514
4515 mainloop();
4516
4517 /* remove plugins (so cleanup code gets run) */
4518 plugins_done();
4519
4520 // Remove the PID file if we wrote it
4521 if (config->wrote_pid && *config->pid_file == '/')
4522 unlink(config->pid_file);
4523
4524 /* kill CLI children */
4525 signal(SIGTERM, SIG_IGN);
4526 kill(0, SIGTERM);
4527 return 0;
4528 }
4529
4530 static void sighup_handler(int sig)
4531 {
4532 main_reload++;
4533 }
4534
4535 static void shutdown_handler(int sig)
4536 {
4537 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4538 }
4539
4540 static void sigchild_handler(int sig)
4541 {
4542 while (waitpid(-1, NULL, WNOHANG) > 0)
4543 ;
4544 }
4545
4546 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4547 {
4548 MD5_CTX ctx;
4549 *challenge_response = NULL;
4550
4551 if (!*config->l2tp_secret)
4552 {
4553 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4554 return;
4555 }
4556
4557 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4558
4559 *challenge_response = calloc(17, 1);
4560
4561 MD5_Init(&ctx);
4562 MD5_Update(&ctx, &id, 1);
4563 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4564 MD5_Update(&ctx, challenge, challenge_length);
4565 MD5_Final(*challenge_response, &ctx);
4566
4567 return;
4568 }
4569
4570 static int facility_value(char *name)
4571 {
4572 int i;
4573 for (i = 0; facilitynames[i].c_name; i++)
4574 {
4575 if (strcmp(facilitynames[i].c_name, name) == 0)
4576 return facilitynames[i].c_val;
4577 }
4578 return 0;
4579 }
4580
4581 static void update_config()
4582 {
4583 int i;
4584 char *p;
4585 static int timeout = 0;
4586 static int interval = 0;
4587
4588 // Update logging
4589 closelog();
4590 syslog_log = 0;
4591 if (log_stream)
4592 {
4593 if (log_stream != stderr)
4594 fclose(log_stream);
4595
4596 log_stream = NULL;
4597 }
4598
4599 if (*config->log_filename)
4600 {
4601 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4602 {
4603 char *p = config->log_filename + 7;
4604 if (*p)
4605 {
4606 openlog("l2tpns", LOG_PID, facility_value(p));
4607 syslog_log = 1;
4608 }
4609 }
4610 else if (strchr(config->log_filename, '/') == config->log_filename)
4611 {
4612 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4613 {
4614 fseek(log_stream, 0, SEEK_END);
4615 setbuf(log_stream, NULL);
4616 }
4617 else
4618 {
4619 log_stream = stderr;
4620 setbuf(log_stream, NULL);
4621 }
4622 }
4623 }
4624 else
4625 {
4626 log_stream = stderr;
4627 setbuf(log_stream, NULL);
4628 }
4629
4630 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4631 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4632
4633 if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
4634 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4635 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4636
4637 // reset MRU/MSS globals
4638 MRU = config->l2tp_mtu - L2TP_HDRS;
4639 if (MRU > PPPoE_MRU)
4640 MRU = PPPoE_MRU;
4641
4642 MSS = MRU - TCP_HDRS;
4643
4644 // Update radius
4645 config->numradiusservers = 0;
4646 for (i = 0; i < MAXRADSERVER; i++)
4647 if (config->radiusserver[i])
4648 {
4649 config->numradiusservers++;
4650 // Set radius port: if not set, take the port from the
4651 // first radius server. For the first radius server,
4652 // take the #defined default value from l2tpns.h
4653
4654 // test twice, In case someone works with
4655 // a secondary radius server without defining
4656 // a primary one, this will work even then.
4657 if (i > 0 && !config->radiusport[i])
4658 config->radiusport[i] = config->radiusport[i-1];
4659 if (!config->radiusport[i])
4660 config->radiusport[i] = RADPORT;
4661 }
4662
4663 if (!config->numradiusservers)
4664 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4665
4666 // parse radius_authtypes_s
4667 config->radius_authtypes = config->radius_authprefer = 0;
4668 p = config->radius_authtypes_s;
4669 while (p && *p)
4670 {
4671 char *s = strpbrk(p, " \t,");
4672 int type = 0;
4673
4674 if (s)
4675 {
4676 *s++ = 0;
4677 while (*s == ' ' || *s == '\t')
4678 s++;
4679
4680 if (!*s)
4681 s = 0;
4682 }
4683
4684 if (!strncasecmp("chap", p, strlen(p)))
4685 type = AUTHCHAP;
4686 else if (!strncasecmp("pap", p, strlen(p)))
4687 type = AUTHPAP;
4688 else
4689 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4690
4691 config->radius_authtypes |= type;
4692 if (!config->radius_authprefer)
4693 config->radius_authprefer = type;
4694
4695 p = s;
4696 }
4697
4698 if (!config->radius_authtypes)
4699 {
4700 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4701 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4702 }
4703
4704 // normalise radius_authtypes_s
4705 if (config->radius_authprefer == AUTHPAP)
4706 {
4707 strcpy(config->radius_authtypes_s, "pap");
4708 if (config->radius_authtypes & AUTHCHAP)
4709 strcat(config->radius_authtypes_s, ", chap");
4710 }
4711 else
4712 {
4713 strcpy(config->radius_authtypes_s, "chap");
4714 if (config->radius_authtypes & AUTHPAP)
4715 strcat(config->radius_authtypes_s, ", pap");
4716 }
4717
4718 if (!config->radius_dae_port)
4719 config->radius_dae_port = DAEPORT;
4720
4721 // re-initialise the random number source
4722 initrandom(config->random_device);
4723
4724 // Update plugins
4725 for (i = 0; i < MAXPLUGINS; i++)
4726 {
4727 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4728 continue;
4729
4730 if (*config->plugins[i])
4731 {
4732 // Plugin added
4733 add_plugin(config->plugins[i]);
4734 }
4735 else if (*config->old_plugins[i])
4736 {
4737 // Plugin removed
4738 remove_plugin(config->old_plugins[i]);
4739 }
4740 }
4741
4742 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4743 if (!config->multi_read_count) config->multi_read_count = 10;
4744 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4745 if (!*config->cluster_interface)
4746 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4747
4748 if (!config->cluster_hb_interval)
4749 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4750
4751 if (!config->cluster_hb_timeout)
4752 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4753
4754 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4755 {
4756 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4757 // late, ensure we're sufficiently larger than that
4758 int t = 4 * config->cluster_hb_interval + 11;
4759
4760 if (config->cluster_hb_timeout < t)
4761 {
4762 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4763 config->cluster_hb_timeout = t;
4764 }
4765
4766 // Push timing changes to the slaves immediately if we're the master
4767 if (config->cluster_iam_master)
4768 cluster_heartbeat();
4769
4770 interval = config->cluster_hb_interval;
4771 timeout = config->cluster_hb_timeout;
4772 }
4773
4774 // Write PID file
4775 if (*config->pid_file == '/' && !config->wrote_pid)
4776 {
4777 FILE *f;
4778 if ((f = fopen(config->pid_file, "w")))
4779 {
4780 fprintf(f, "%d\n", getpid());
4781 fclose(f);
4782 config->wrote_pid = 1;
4783 }
4784 else
4785 {
4786 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4787 }
4788 }
4789 }
4790
4791 static void read_config_file()
4792 {
4793 FILE *f;
4794
4795 if (!config->config_file) return;
4796 if (!(f = fopen(config->config_file, "r")))
4797 {
4798 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4799 return;
4800 }
4801
4802 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4803 cli_do_file(f);
4804 LOG(3, 0, 0, "Done reading config file\n");
4805 fclose(f);
4806 }
4807
4808 int sessionsetup(sessionidt s, tunnelidt t)
4809 {
4810 // A session now exists, set it up
4811 in_addr_t ip;
4812 char *user;
4813 sessionidt i;
4814 int r;
4815
4816 CSTAT(sessionsetup);
4817
4818 LOG(3, s, t, "Doing session setup for session\n");
4819
4820 if (!session[s].ip)
4821 {
4822 assign_ip_address(s);
4823 if (!session[s].ip)
4824 {
4825 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4826 sessionshutdown(s, "No IP addresses available.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
4827 return 0;
4828 }
4829 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4830 fmtaddr(htonl(session[s].ip), 0));
4831 }
4832
4833
4834 // Make sure this is right
4835 session[s].tunnel = t;
4836
4837 // Join a bundle if the MRRU option is accepted
4838 if (session[s].mrru > 0 && !session[s].bundle)
4839 {
4840 LOG(3, s, t, "This session can be part of multilink bundle\n");
4841 if (join_bundle(s))
4842 cluster_send_bundle(session[s].bundle);
4843 }
4844
4845 // zap old sessions with same IP and/or username
4846 // Don't kill gardened sessions - doing so leads to a DoS
4847 // from someone who doesn't need to know the password
4848 {
4849 ip = session[s].ip;
4850 user = session[s].user;
4851 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4852 {
4853 if (i == s) continue;
4854 if (!session[s].opened) continue;
4855 if (ip == session[i].ip)
4856 {
4857 sessionkill(i, "Duplicate IP address");
4858 continue;
4859 }
4860
4861 if (config->allow_duplicate_users)
4862 continue;
4863
4864 if (session[s].walled_garden || session[i].walled_garden)
4865 continue;
4866
4867 // Allow duplicate sessions for guest account.
4868 if (*config->guest_user && !strcasecmp(user, config->guest_user))
4869 continue;
4870
4871 // Allow duplicate sessions for multilink ones of the same bundle.
4872 if (session[s].bundle && session[i].bundle && session[s].bundle == session[i].bundle)
4873 continue;
4874
4875 // Drop the new session in case of duplicate sessionss, not the old one.
4876 if (!strcasecmp(user, session[i].user))
4877 sessionkill(i, "Duplicate session for users");
4878 }
4879 }
4880
4881 {
4882 int routed = 0;
4883
4884 // Add the route for this session.
4885 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4886 {
4887 if ((session[s].ip & session[s].route[r].mask) ==
4888 (session[s].route[r].ip & session[s].route[r].mask))
4889 routed++;
4890
4891 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4892 }
4893
4894 // Static IPs need to be routed if not already
4895 // convered by a Framed-Route. Anything else is part
4896 // of the IP address pool and is already routed, it
4897 // just needs to be added to the IP cache.
4898 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4899 if (session[s].ip_pool_index == -1) // static ip
4900 {
4901 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4902 }
4903 else
4904 cache_ipmap(session[s].ip, s);
4905 }
4906
4907 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4908 lcp_open(s, t); // transition to Network phase and send initial IPCP
4909
4910 // Run the plugin's against this new session.
4911 {
4912 struct param_new_session data = { &tunnel[t], &session[s] };
4913 run_plugins(PLUGIN_NEW_SESSION, &data);
4914 }
4915
4916 // Allocate TBFs if throttled
4917 if (session[s].throttle_in || session[s].throttle_out)
4918 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4919
4920 session[s].last_packet = session[s].last_data = time_now;
4921
4922 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4923 fmtaddr(htonl(session[s].ip), 0),
4924 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4925
4926 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4927
4928 return 1; // RADIUS OK and IP allocated, done...
4929 }
4930
4931 //
4932 // This session just got dropped on us by the master or something.
4933 // Make sure our tables up up to date...
4934 //
4935 int load_session(sessionidt s, sessiont *new)
4936 {
4937 int i;
4938 int newip = 0;
4939
4940 // Sanity checks.
4941 if (new->ip_pool_index >= MAXIPPOOL ||
4942 new->tunnel >= MAXTUNNEL)
4943 {
4944 LOG(0, s, 0, "Strange session update received!\n");
4945 // FIXME! What to do here?
4946 return 0;
4947 }
4948
4949 //
4950 // Ok. All sanity checks passed. Now we're committed to
4951 // loading the new session.
4952 //
4953
4954 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4955
4956 // See if routes/ip cache need updating
4957 if (new->ip != session[s].ip)
4958 newip++;
4959
4960 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4961 if (new->route[i].ip != session[s].route[i].ip ||
4962 new->route[i].mask != session[s].route[i].mask)
4963 newip++;
4964
4965 // needs update
4966 if (newip)
4967 {
4968 int routed = 0;
4969
4970 // remove old routes...
4971 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4972 {
4973 if ((session[s].ip & session[s].route[i].mask) ==
4974 (session[s].route[i].ip & session[s].route[i].mask))
4975 routed++;
4976
4977 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4978 }
4979
4980 // ...ip
4981 if (session[s].ip)
4982 {
4983 if (session[s].ip_pool_index == -1) // static IP
4984 {
4985 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4986 }
4987 else // It's part of the IP pool, remove it manually.
4988 uncache_ipmap(session[s].ip);
4989 }
4990
4991 routed = 0;
4992
4993 // add new routes...
4994 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4995 {
4996 if ((new->ip & new->route[i].mask) ==
4997 (new->route[i].ip & new->route[i].mask))
4998 routed++;
4999
5000 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
5001 }
5002
5003 // ...ip
5004 if (new->ip)
5005 {
5006 // If there's a new one, add it.
5007 if (new->ip_pool_index == -1)
5008 {
5009 if (!routed) routeset(s, new->ip, 0, 0, 1);
5010 }
5011 else
5012 cache_ipmap(new->ip, s);
5013 }
5014 }
5015
5016 // check v6 routing
5017 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
5018 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
5019
5020 // check filters
5021 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
5022 {
5023 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %u\n", (int) new->filter_in);
5024 new->filter_in = 0;
5025 }
5026
5027 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
5028 {
5029 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %u\n", (int) new->filter_out);
5030 new->filter_out = 0;
5031 }
5032
5033 if (new->filter_in != session[s].filter_in)
5034 {
5035 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
5036 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
5037 }
5038
5039 if (new->filter_out != session[s].filter_out)
5040 {
5041 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
5042 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
5043 }
5044
5045 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
5046 // for walking the sessions to forward byte counts to the master.
5047 config->cluster_highest_sessionid = s;
5048
5049 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
5050
5051 // Do fixups into address pool.
5052 if (new->ip_pool_index != -1)
5053 fix_address_pool(s);
5054
5055 return 1;
5056 }
5057
5058 static void initplugins()
5059 {
5060 int i;
5061
5062 loaded_plugins = ll_init();
5063 // Initialize the plugins to nothing
5064 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
5065 plugins[i] = ll_init();
5066 }
5067
5068 static void *open_plugin(char *plugin_name, int load)
5069 {
5070 char path[256] = "";
5071
5072 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
5073 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
5074 return dlopen(path, RTLD_NOW);
5075 }
5076
5077 // plugin callback to get a config value
5078 static void *getconfig(char *key, enum config_typet type)
5079 {
5080 int i;
5081
5082 for (i = 0; config_values[i].key; i++)
5083 {
5084 if (!strcmp(config_values[i].key, key))
5085 {
5086 if (config_values[i].type == type)
5087 return ((void *) config) + config_values[i].offset;
5088
5089 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
5090 key, type, config_values[i].type);
5091
5092 return 0;
5093 }
5094 }
5095
5096 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
5097 return 0;
5098 }
5099
5100 static int add_plugin(char *plugin_name)
5101 {
5102 static struct pluginfuncs funcs = {
5103 _log,
5104 _log_hex,
5105 fmtaddr,
5106 sessionbyuser,
5107 sessiontbysessionidt,
5108 sessionidtbysessiont,
5109 radiusnew,
5110 radiussend,
5111 getconfig,
5112 sessionshutdown,
5113 sessionkill,
5114 throttle_session,
5115 cluster_send_session,
5116 };
5117
5118 void *p = open_plugin(plugin_name, 1);
5119 int (*initfunc)(struct pluginfuncs *);
5120 int i;
5121
5122 if (!p)
5123 {
5124 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
5125 return -1;
5126 }
5127
5128 if (ll_contains(loaded_plugins, p))
5129 {
5130 dlclose(p);
5131 return 0; // already loaded
5132 }
5133
5134 {
5135 int *v = dlsym(p, "plugin_api_version");
5136 if (!v || *v != PLUGIN_API_VERSION)
5137 {
5138 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
5139 dlclose(p);
5140 return -1;
5141 }
5142 }
5143
5144 if ((initfunc = dlsym(p, "plugin_init")))
5145 {
5146 if (!initfunc(&funcs))
5147 {
5148 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
5149 dlclose(p);
5150 return -1;
5151 }
5152 }
5153
5154 ll_push(loaded_plugins, p);
5155
5156 for (i = 0; i < max_plugin_functions; i++)
5157 {
5158 void *x;
5159 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5160 {
5161 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
5162 ll_push(plugins[i], x);
5163 }
5164 }
5165
5166 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
5167 return 1;
5168 }
5169
5170 static void run_plugin_done(void *plugin)
5171 {
5172 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
5173
5174 if (donefunc)
5175 donefunc();
5176 }
5177
5178 static int remove_plugin(char *plugin_name)
5179 {
5180 void *p = open_plugin(plugin_name, 0);
5181 int loaded = 0;
5182
5183 if (!p)
5184 return -1;
5185
5186 if (ll_contains(loaded_plugins, p))
5187 {
5188 int i;
5189 for (i = 0; i < max_plugin_functions; i++)
5190 {
5191 void *x;
5192 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5193 ll_delete(plugins[i], x);
5194 }
5195
5196 ll_delete(loaded_plugins, p);
5197 run_plugin_done(p);
5198 loaded = 1;
5199 }
5200
5201 dlclose(p);
5202 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
5203 return loaded;
5204 }
5205
5206 int run_plugins(int plugin_type, void *data)
5207 {
5208 int (*func)(void *data);
5209
5210 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
5211 return PLUGIN_RET_ERROR;
5212
5213 ll_reset(plugins[plugin_type]);
5214 while ((func = ll_next(plugins[plugin_type])))
5215 {
5216 int r = func(data);
5217
5218 if (r != PLUGIN_RET_OK)
5219 return r; // stop here
5220 }
5221
5222 return PLUGIN_RET_OK;
5223 }
5224
5225 static void plugins_done()
5226 {
5227 void *p;
5228
5229 ll_reset(loaded_plugins);
5230 while ((p = ll_next(loaded_plugins)))
5231 run_plugin_done(p);
5232 }
5233
5234 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
5235 {
5236 struct nsctl request;
5237 struct nsctl response;
5238 int type = unpack_control(&request, buf, len);
5239 int r;
5240 void *p;
5241
5242 if (log_stream && config->debug >= 4)
5243 {
5244 if (type < 0)
5245 {
5246 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
5247 fmtaddr(addr->sin_addr.s_addr, 0), type);
5248 }
5249 else
5250 {
5251 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5252 dump_control(&request, log_stream);
5253 }
5254 }
5255
5256 switch (type)
5257 {
5258 case NSCTL_REQ_LOAD:
5259 if (request.argc != 1)
5260 {
5261 response.type = NSCTL_RES_ERR;
5262 response.argc = 1;
5263 response.argv[0] = "name of plugin required";
5264 }
5265 else if ((r = add_plugin(request.argv[0])) < 1)
5266 {
5267 response.type = NSCTL_RES_ERR;
5268 response.argc = 1;
5269 response.argv[0] = !r
5270 ? "plugin already loaded"
5271 : "error loading plugin";
5272 }
5273 else
5274 {
5275 response.type = NSCTL_RES_OK;
5276 response.argc = 0;
5277 }
5278
5279 break;
5280
5281 case NSCTL_REQ_UNLOAD:
5282 if (request.argc != 1)
5283 {
5284 response.type = NSCTL_RES_ERR;
5285 response.argc = 1;
5286 response.argv[0] = "name of plugin required";
5287 }
5288 else if ((r = remove_plugin(request.argv[0])) < 1)
5289 {
5290 response.type = NSCTL_RES_ERR;
5291 response.argc = 1;
5292 response.argv[0] = !r
5293 ? "plugin not loaded"
5294 : "plugin not found";
5295 }
5296 else
5297 {
5298 response.type = NSCTL_RES_OK;
5299 response.argc = 0;
5300 }
5301
5302 break;
5303
5304 case NSCTL_REQ_HELP:
5305 response.type = NSCTL_RES_OK;
5306 response.argc = 0;
5307
5308 ll_reset(loaded_plugins);
5309 while ((p = ll_next(loaded_plugins)))
5310 {
5311 char **help = dlsym(p, "plugin_control_help");
5312 while (response.argc < 0xff && help && *help)
5313 response.argv[response.argc++] = *help++;
5314 }
5315
5316 break;
5317
5318 case NSCTL_REQ_CONTROL:
5319 {
5320 struct param_control param = {
5321 config->cluster_iam_master,
5322 request.argc,
5323 request.argv,
5324 0,
5325 NULL,
5326 };
5327
5328 int r = run_plugins(PLUGIN_CONTROL, &param);
5329
5330 if (r == PLUGIN_RET_ERROR)
5331 {
5332 response.type = NSCTL_RES_ERR;
5333 response.argc = 1;
5334 response.argv[0] = param.additional
5335 ? param.additional
5336 : "error returned by plugin";
5337 }
5338 else if (r == PLUGIN_RET_NOTMASTER)
5339 {
5340 static char msg[] = "must be run on master: 000.000.000.000";
5341
5342 response.type = NSCTL_RES_ERR;
5343 response.argc = 1;
5344 if (config->cluster_master_address)
5345 {
5346 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5347 response.argv[0] = msg;
5348 }
5349 else
5350 {
5351 response.argv[0] = "must be run on master: none elected";
5352 }
5353 }
5354 else if (!(param.response & NSCTL_RESPONSE))
5355 {
5356 response.type = NSCTL_RES_ERR;
5357 response.argc = 1;
5358 response.argv[0] = param.response
5359 ? "unrecognised response value from plugin"
5360 : "unhandled action";
5361 }
5362 else
5363 {
5364 response.type = param.response;
5365 response.argc = 0;
5366 if (param.additional)
5367 {
5368 response.argc = 1;
5369 response.argv[0] = param.additional;
5370 }
5371 }
5372 }
5373
5374 break;
5375
5376 default:
5377 response.type = NSCTL_RES_ERR;
5378 response.argc = 1;
5379 response.argv[0] = "error unpacking control packet";
5380 }
5381
5382 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5383 if (!buf)
5384 {
5385 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5386 return;
5387 }
5388
5389 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5390 if (r > 0)
5391 {
5392 sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
5393 if (log_stream && config->debug >= 4)
5394 {
5395 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5396 dump_control(&response, log_stream);
5397 }
5398 }
5399 else
5400 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5401 fmtaddr(addr->sin_addr.s_addr, 0), r);
5402
5403 free(buf);
5404 }
5405
5406 static tunnelidt new_tunnel()
5407 {
5408 tunnelidt i;
5409 for (i = 1; i < MAXTUNNEL; i++)
5410 {
5411 if (tunnel[i].state == TUNNELFREE)
5412 {
5413 LOG(4, 0, i, "Assigning tunnel ID %u\n", i);
5414 if (i > config->cluster_highest_tunnelid)
5415 config->cluster_highest_tunnelid = i;
5416 return i;
5417 }
5418 }
5419 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5420 return 0;
5421 }
5422
5423 //
5424 // We're becoming the master. Do any required setup..
5425 //
5426 // This is principally telling all the plugins that we're
5427 // now a master, and telling them about all the sessions
5428 // that are active too..
5429 //
5430 void become_master(void)
5431 {
5432 int s, i;
5433 static struct event_data d[RADIUS_FDS];
5434 struct epoll_event e;
5435
5436 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5437
5438 // running a bunch of iptables commands is slow and can cause
5439 // the master to drop tunnels on takeover--kludge around the
5440 // problem by forking for the moment (note: race)
5441 if (!fork_and_close())
5442 {
5443 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5444 {
5445 if (!session[s].opened) // Not an in-use session.
5446 continue;
5447
5448 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5449 }
5450 exit(0);
5451 }
5452
5453 // add radius fds
5454 e.events = EPOLLIN;
5455 for (i = 0; i < RADIUS_FDS; i++)
5456 {
5457 d[i].type = FD_TYPE_RADIUS;
5458 d[i].index = i;
5459 e.data.ptr = &d[i];
5460
5461 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5462 }
5463 }
5464
5465 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5466 {
5467 int s, i;
5468 int count = 0;
5469 int buckets[64];
5470
5471 if (CLI_HELP_REQUESTED)
5472 return CLI_HELP_NO_ARGS;
5473
5474 time(&time_now);
5475 for (i = 0; i < 64;++i) buckets[i] = 0;
5476
5477 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5478 {
5479 int idle;
5480 if (!session[s].opened)
5481 continue;
5482
5483 idle = time_now - session[s].last_data;
5484 idle /= 5 ; // In multiples of 5 seconds.
5485 if (idle < 0)
5486 idle = 0;
5487 if (idle > 63)
5488 idle = 63;
5489
5490 ++count;
5491 ++buckets[idle];
5492 }
5493
5494 for (i = 0; i < 63; ++i)
5495 {
5496 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5497 }
5498 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5499 cli_print(cli, "%d total sessions open.", count);
5500 return CLI_OK;
5501 }
5502
5503 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5504 {
5505 int s, i;
5506 int count = 0;
5507 int buckets[64];
5508
5509 if (CLI_HELP_REQUESTED)
5510 return CLI_HELP_NO_ARGS;
5511
5512 time(&time_now);
5513 for (i = 0; i < 64;++i) buckets[i] = 0;
5514
5515 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5516 {
5517 int open = 0, d;
5518 if (!session[s].opened)
5519 continue;
5520
5521 d = time_now - session[s].opened;
5522 if (d < 0)
5523 d = 0;
5524 while (d > 1 && open < 32)
5525 {
5526 ++open;
5527 d >>= 1; // half.
5528 }
5529 ++count;
5530 ++buckets[open];
5531 }
5532
5533 s = 1;
5534 for (i = 0; i < 30; ++i)
5535 {
5536 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5537 s <<= 1;
5538 }
5539 cli_print(cli, "%d total sessions open.", count);
5540 return CLI_OK;
5541 }
5542
5543 /* Unhide an avp.
5544 *
5545 * This unencodes the AVP using the L2TP secret and the previously
5546 * stored random vector. It overwrites the hidden data with the
5547 * unhidden AVP subformat.
5548 */
5549 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5550 {
5551 MD5_CTX ctx;
5552 uint8_t digest[16];
5553 uint8_t *last;
5554 size_t d = 0;
5555 uint16_t m = htons(type);
5556
5557 // Compute initial pad
5558 MD5_Init(&ctx);
5559 MD5_Update(&ctx, (unsigned char *) &m, 2);
5560 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5561 MD5_Update(&ctx, vector, vec_len);
5562 MD5_Final(digest, &ctx);
5563
5564 // pointer to last decoded 16 octets
5565 last = value;
5566
5567 while (len > 0)
5568 {
5569 // calculate a new pad based on the last decoded block
5570 if (d >= sizeof(digest))
5571 {
5572 MD5_Init(&ctx);
5573 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5574 MD5_Update(&ctx, last, sizeof(digest));
5575 MD5_Final(digest, &ctx);
5576
5577 d = 0;
5578 last = value;
5579 }
5580
5581 *value++ ^= digest[d++];
5582 len--;
5583 }
5584 }
5585
5586 int find_filter(char const *name, size_t len)
5587 {
5588 int free = -1;
5589 int i;
5590
5591 for (i = 0; i < MAXFILTER; i++)
5592 {
5593 if (!*ip_filters[i].name)
5594 {
5595 if (free < 0)
5596 free = i;
5597
5598 continue;
5599 }
5600
5601 if (strlen(ip_filters[i].name) != len)
5602 continue;
5603
5604 if (!strncmp(ip_filters[i].name, name, len))
5605 return i;
5606 }
5607
5608 return free;
5609 }
5610
5611 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5612 {
5613 switch (p->op)
5614 {
5615 case FILTER_PORT_OP_EQ: return port == p->port;
5616 case FILTER_PORT_OP_NEQ: return port != p->port;
5617 case FILTER_PORT_OP_GT: return port > p->port;
5618 case FILTER_PORT_OP_LT: return port < p->port;
5619 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5620 }
5621
5622 return 0;
5623 }
5624
5625 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5626 {
5627 switch (op)
5628 {
5629 case FILTER_FLAG_OP_ANY:
5630 return (flags & sflags) || (~flags & cflags);
5631
5632 case FILTER_FLAG_OP_ALL:
5633 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5634
5635 case FILTER_FLAG_OP_EST:
5636 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5637 }
5638
5639 return 0;
5640 }
5641
5642 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5643 {
5644 uint16_t frag_offset;
5645 uint8_t proto;
5646 in_addr_t src_ip;
5647 in_addr_t dst_ip;
5648 uint16_t src_port = 0;
5649 uint16_t dst_port = 0;
5650 uint8_t flags = 0;
5651 ip_filter_rulet *rule;
5652
5653 if (len < 20) // up to end of destination address
5654 return 0;
5655
5656 if ((*buf >> 4) != 4) // IPv4
5657 return 0;
5658
5659 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5660 proto = buf[9];
5661 src_ip = *(in_addr_t *) (buf + 12);
5662 dst_ip = *(in_addr_t *) (buf + 16);
5663
5664 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5665 {
5666 int l = (buf[0] & 0xf) * 4; // length of IP header
5667 if (len < l + 4) // ports
5668 return 0;
5669
5670 src_port = ntohs(*(uint16_t *) (buf + l));
5671 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5672 if (proto == IPPROTO_TCP)
5673 {
5674 if (len < l + 14) // flags
5675 return 0;
5676
5677 flags = buf[l + 13] & 0x3f;
5678 }
5679 }
5680
5681 for (rule = ip_filters[filter].rules; rule->action; rule++)
5682 {
5683 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5684 continue;
5685
5686 if (rule->src_wild != INADDR_BROADCAST &&
5687 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5688 continue;
5689
5690 if (rule->dst_wild != INADDR_BROADCAST &&
5691 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5692 continue;
5693
5694 if (frag_offset)
5695 {
5696 // layer 4 deny rules are skipped
5697 if (rule->action == FILTER_ACTION_DENY &&
5698 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
5699 continue;
5700 }
5701 else
5702 {
5703 if (rule->frag)
5704 continue;
5705
5706 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5707 {
5708 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5709 continue;
5710
5711 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5712 continue;
5713
5714 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5715 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5716 continue;
5717 }
5718 }
5719
5720 // matched
5721 rule->counter++;
5722 return rule->action == FILTER_ACTION_PERMIT;
5723 }
5724
5725 // default deny
5726 return 0;
5727 }