598e3ab96abd0fbf51d33388c3fb72c029bf05a2
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.160 2006-04-13 11:14:35 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("bind_address", bind_address, IPv4),
131 CONFIG("peer_address", peer_address, IPv4),
132 CONFIG("send_garp", send_garp, BOOL),
133 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
134 CONFIG("throttle_buckets", num_tbfs, INT),
135 CONFIG("accounting_dir", accounting_dir, STRING),
136 CONFIG("setuid", target_uid, INT),
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 sessiont *session = NULL; // Array of session structures.
178 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
179 radiust *radius = NULL; // Array of radius structures.
180 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
181 ip_filtert *ip_filters = NULL; // Array of named filters.
182 static controlt *controlfree = 0;
183 struct Tstats *_statistics = NULL;
184 #ifdef RINGBUFFER
185 struct Tringbuffer *ringbuffer = NULL;
186 #endif
187
188 static void cache_ipmap(in_addr_t ip, int s);
189 static void uncache_ipmap(in_addr_t ip);
190 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
191 static void free_ip_address(sessionidt s);
192 static void dump_acct_info(int all);
193 static void sighup_handler(int sig);
194 static void shutdown_handler(int sig);
195 static void sigchild_handler(int sig);
196 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
197 static void update_config(void);
198 static void read_config_file(void);
199 static void initplugins(void);
200 static int add_plugin(char *plugin_name);
201 static int remove_plugin(char *plugin_name);
202 static void plugins_done(void);
203 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
204 static tunnelidt new_tunnel(void);
205 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
206
207 // on slaves, alow BGP to withdraw cleanly before exiting
208 #define QUIT_DELAY 5
209
210 // quit actions (master)
211 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
212 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
213
214 // return internal time (10ths since process startup), set f if given
215 // as a side-effect sets time_now, and time_changed
216 static clockt now(double *f)
217 {
218 struct timeval t;
219 gettimeofday(&t, 0);
220 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
221 if (t.tv_sec != time_now)
222 {
223 time_now = t.tv_sec;
224 time_changed++;
225 }
226 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
227 }
228
229 // work out a retry time based on try number
230 // This is a straight bounded exponential backoff.
231 // Maximum re-try time is 32 seconds. (2^5).
232 clockt backoff(uint8_t try)
233 {
234 if (try > 5) try = 5; // max backoff
235 return now(NULL) + 10 * (1 << try);
236 }
237
238
239 //
240 // Log a debug message. Typically called via the LOG macro
241 //
242 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
243 {
244 static char message[65536] = {0};
245 va_list ap;
246
247 #ifdef RINGBUFFER
248 if (ringbuffer)
249 {
250 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
251 ringbuffer->tail = 0;
252 if (ringbuffer->tail == ringbuffer->head)
253 if (++ringbuffer->head >= RINGBUFFER_SIZE)
254 ringbuffer->head = 0;
255
256 ringbuffer->buffer[ringbuffer->tail].level = level;
257 ringbuffer->buffer[ringbuffer->tail].session = s;
258 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
259 va_start(ap, format);
260 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
261 va_end(ap);
262 }
263 #endif
264
265 if (config->debug < level) return;
266
267 va_start(ap, format);
268 vsnprintf(message, sizeof(message), format, ap);
269
270 if (log_stream)
271 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
272 else if (syslog_log)
273 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
274
275 va_end(ap);
276 }
277
278 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
279 {
280 int i, j;
281 const uint8_t *d = data;
282
283 if (config->debug < level) return;
284
285 // No support for _log_hex to syslog
286 if (log_stream)
287 {
288 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
289 setvbuf(log_stream, NULL, _IOFBF, 16384);
290
291 for (i = 0; i < maxsize; )
292 {
293 fprintf(log_stream, "%4X: ", i);
294 for (j = i; j < maxsize && j < (i + 16); j++)
295 {
296 fprintf(log_stream, "%02X ", d[j]);
297 if (j == i + 7)
298 fputs(": ", log_stream);
299 }
300
301 for (; j < i + 16; j++)
302 {
303 fputs(" ", log_stream);
304 if (j == i + 7)
305 fputs(": ", log_stream);
306 }
307
308 fputs(" ", log_stream);
309 for (j = i; j < maxsize && j < (i + 16); j++)
310 {
311 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
312 fputc(d[j], log_stream);
313 else
314 fputc('.', log_stream);
315
316 if (j == i + 7)
317 fputs(" ", log_stream);
318 }
319
320 i = j;
321 fputs("\n", log_stream);
322 }
323
324 fflush(log_stream);
325 setbuf(log_stream, NULL);
326 }
327 }
328
329 // update a counter, accumulating 2^32 wraps
330 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
331 {
332 uint32_t new = *counter + delta;
333 if (new < *counter)
334 (*wrap)++;
335
336 *counter = new;
337 }
338
339 // initialise the random generator
340 static void initrandom(char *source)
341 {
342 static char path[sizeof(config->random_device)] = "*undefined*";
343
344 // reinitialise only if we are forced to do so or if the config has changed
345 if (source && !strncmp(path, source, sizeof(path)))
346 return;
347
348 // close previous source, if any
349 if (rand_fd >= 0)
350 close(rand_fd);
351
352 rand_fd = -1;
353
354 if (source)
355 {
356 // register changes
357 snprintf(path, sizeof(path), "%s", source);
358
359 if (*path == '/')
360 {
361 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
362 if (rand_fd < 0)
363 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
364 path, strerror(errno));
365 }
366 }
367 }
368
369 // fill buffer with random data
370 void random_data(uint8_t *buf, int len)
371 {
372 int n = 0;
373
374 CSTAT(random_data);
375 if (rand_fd >= 0)
376 {
377 n = read(rand_fd, buf, len);
378 if (n >= len) return;
379 if (n < 0)
380 {
381 if (errno != EAGAIN)
382 {
383 LOG(0, 0, 0, "Error reading from random source: %s\n",
384 strerror(errno));
385
386 // fall back to rand()
387 initrandom(NULL);
388 }
389
390 n = 0;
391 }
392 }
393
394 // append missing data
395 while (n < len)
396 // not using the low order bits from the prng stream
397 buf[n++] = (rand() >> 4) & 0xff;
398 }
399
400 // Add a route
401 //
402 // This adds it to the routing table, advertises it
403 // via BGP if enabled, and stuffs it into the
404 // 'sessionbyip' cache.
405 //
406 // 'ip' and 'mask' must be in _host_ order.
407 //
408 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
409 {
410 struct rtentry r;
411 int i;
412
413 if (!mask) mask = 0xffffffff;
414
415 ip &= mask; // Force the ip to be the first one in the route.
416
417 memset(&r, 0, sizeof(r));
418 r.rt_dev = config->tundevice;
419 r.rt_dst.sa_family = AF_INET;
420 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
421 r.rt_gateway.sa_family = AF_INET;
422 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
423 r.rt_genmask.sa_family = AF_INET;
424 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
425 r.rt_flags = (RTF_UP | RTF_STATIC);
426 if (gw)
427 r.rt_flags |= RTF_GATEWAY;
428 else if (mask == 0xffffffff)
429 r.rt_flags |= RTF_HOST;
430
431 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
432 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
433 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
434
435 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
436 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
437
438 #ifdef BGP
439 if (add)
440 bgp_add_route(htonl(ip), htonl(mask));
441 else
442 bgp_del_route(htonl(ip), htonl(mask));
443 #endif /* BGP */
444
445 // Add/Remove the IPs to the 'sessionbyip' cache.
446 // Note that we add the zero address in the case of
447 // a network route. Roll on CIDR.
448
449 // Note that 's == 0' implies this is the address pool.
450 // We still cache it here, because it will pre-fill
451 // the malloc'ed tree.
452
453 if (s)
454 {
455 if (!add) // Are we deleting a route?
456 s = 0; // Caching the session as '0' is the same as uncaching.
457
458 for (i = ip; (i&mask) == (ip&mask) ; ++i)
459 cache_ipmap(i, s);
460 }
461 }
462
463 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
464 {
465 struct in6_rtmsg rt;
466 char ipv6addr[INET6_ADDRSTRLEN];
467
468 if (ifr6fd < 0)
469 {
470 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
471 return;
472 }
473
474 memset(&rt, 0, sizeof(rt));
475
476 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
477 rt.rtmsg_dst_len = prefixlen;
478 rt.rtmsg_metric = 1;
479 rt.rtmsg_flags = RTF_UP;
480 rt.rtmsg_ifindex = tunidx;
481
482 LOG(1, 0, 0, "Route %s %s/%d\n",
483 add ? "add" : "del",
484 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
485 prefixlen);
486
487 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
488 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
489 strerror(errno));
490
491 // FIXME: need to add BGP routing (RFC2858)
492
493 if (s)
494 {
495 if (!add) // Are we deleting a route?
496 s = 0; // Caching the session as '0' is the same as uncaching.
497
498 cache_ipv6map(ip, prefixlen, s);
499 }
500
501 return;
502 }
503
504 // defined in linux/ipv6.h, but tricky to include from user-space
505 // TODO: move routing to use netlink rather than ioctl
506 struct in6_ifreq {
507 struct in6_addr ifr6_addr;
508 __u32 ifr6_prefixlen;
509 unsigned int ifr6_ifindex;
510 };
511
512 //
513 // Set up TUN interface
514 static void inittun(void)
515 {
516 struct ifreq ifr;
517 struct in6_ifreq ifr6;
518 struct sockaddr_in sin = {0};
519 memset(&ifr, 0, sizeof(ifr));
520 ifr.ifr_flags = IFF_TUN;
521
522 tunfd = open(TUNDEVICE, O_RDWR);
523 if (tunfd < 0)
524 { // fatal
525 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
526 exit(1);
527 }
528 {
529 int flags = fcntl(tunfd, F_GETFL, 0);
530 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
531 }
532 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
533 {
534 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
535 exit(1);
536 }
537 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
538 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
539 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
540
541 sin.sin_family = AF_INET;
542 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
543 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
544
545 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
546 {
547 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
548 exit(1);
549 }
550 /* Bump up the qlen to deal with bursts from the network */
551 ifr.ifr_qlen = 1000;
552 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
553 {
554 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
555 exit(1);
556 }
557 /* set MTU to modem MRU */
558 ifr.ifr_mtu = MRU;
559 if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
560 {
561 LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
562 exit(1);
563 }
564 ifr.ifr_flags = IFF_UP;
565 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
566 {
567 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
568 exit(1);
569 }
570 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
571 {
572 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
573 exit(1);
574 }
575 tunidx = ifr.ifr_ifindex;
576
577 // Only setup IPv6 on the tun device if we have a configured prefix
578 if (config->ipv6_prefix.s6_addr[0]) {
579 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
580
581 // Link local address is FE80::1
582 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
583 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
584 ifr6.ifr6_addr.s6_addr[1] = 0x80;
585 ifr6.ifr6_addr.s6_addr[15] = 1;
586 ifr6.ifr6_prefixlen = 64;
587 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
588 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
589 {
590 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
591 " %s\n", strerror(errno));
592 }
593
594 // Global address is prefix::1
595 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
596 ifr6.ifr6_addr = config->ipv6_prefix;
597 ifr6.ifr6_addr.s6_addr[15] = 1;
598 ifr6.ifr6_prefixlen = 64;
599 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
600 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
601 {
602 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
603 strerror(errno));
604 }
605 }
606 }
607
608 // set up UDP ports
609 static void initudp(void)
610 {
611 int on = 1;
612 struct sockaddr_in addr;
613
614 // Tunnel
615 memset(&addr, 0, sizeof(addr));
616 addr.sin_family = AF_INET;
617 addr.sin_port = htons(L2TPPORT);
618 addr.sin_addr.s_addr = config->bind_address;
619 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
620 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
621 {
622 int flags = fcntl(udpfd, F_GETFL, 0);
623 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
624 }
625 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
626 {
627 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
628 exit(1);
629 }
630
631 // Control
632 memset(&addr, 0, sizeof(addr));
633 addr.sin_family = AF_INET;
634 addr.sin_port = htons(NSCTL_PORT);
635 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
636 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
637 setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
638 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
639 {
640 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
641 exit(1);
642 }
643
644 // Dynamic Authorization Extensions to RADIUS
645 memset(&addr, 0, sizeof(addr));
646 addr.sin_family = AF_INET;
647 addr.sin_port = htons(config->radius_dae_port);
648 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
649 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
650 setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
651 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
652 {
653 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
654 exit(1);
655 }
656
657 // Intercept
658 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
659 }
660
661 //
662 // Find session by IP, < 1 for not found
663 //
664 // Confusingly enough, this 'ip' must be
665 // in _network_ order. This being the common
666 // case when looking it up from IP packet headers.
667 //
668 // We actually use this cache for two things.
669 // #1. For used IP addresses, this maps to the
670 // session ID that it's used by.
671 // #2. For un-used IP addresses, this maps to the
672 // index into the pool table that contains that
673 // IP address.
674 //
675
676 static int lookup_ipmap(in_addr_t ip)
677 {
678 uint8_t *a = (uint8_t *) &ip;
679 uint8_t **d = (uint8_t **) ip_hash;
680
681 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
682 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
683 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
684
685 return (int) (intptr_t) d[(size_t) *a];
686 }
687
688 static int lookup_ipv6map(struct in6_addr ip)
689 {
690 struct ipv6radix *curnode;
691 int i;
692 int s;
693 char ipv6addr[INET6_ADDRSTRLEN];
694
695 curnode = &ipv6_hash[ip.s6_addr[0]];
696 i = 1;
697 s = curnode->sess;
698
699 while (s == 0 && i < 15 && curnode->branch != NULL)
700 {
701 curnode = &curnode->branch[ip.s6_addr[i]];
702 s = curnode->sess;
703 i++;
704 }
705
706 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
707 inet_ntop(AF_INET6, &ip, ipv6addr,
708 INET6_ADDRSTRLEN),
709 s);
710
711 return s;
712 }
713
714 sessionidt sessionbyip(in_addr_t ip)
715 {
716 int s = lookup_ipmap(ip);
717 CSTAT(sessionbyip);
718
719 if (s > 0 && s < MAXSESSION && session[s].opened)
720 return (sessionidt) s;
721
722 return 0;
723 }
724
725 sessionidt sessionbyipv6(struct in6_addr ip)
726 {
727 int s;
728 CSTAT(sessionbyipv6);
729
730 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
731 (ip.s6_addr[0] == 0xFE &&
732 ip.s6_addr[1] == 0x80 &&
733 ip.s6_addr16[1] == 0 &&
734 ip.s6_addr16[2] == 0 &&
735 ip.s6_addr16[3] == 0)) {
736 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
737 } else {
738 s = lookup_ipv6map(ip);
739 }
740
741 if (s > 0 && s < MAXSESSION && session[s].opened)
742 return s;
743
744 return 0;
745 }
746
747 //
748 // Take an IP address in HOST byte order and
749 // add it to the sessionid by IP cache.
750 //
751 // (It's actually cached in network order)
752 //
753 static void cache_ipmap(in_addr_t ip, int s)
754 {
755 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
756 uint8_t *a = (uint8_t *) &nip;
757 uint8_t **d = (uint8_t **) ip_hash;
758 int i;
759
760 for (i = 0; i < 3; i++)
761 {
762 if (!d[(size_t) a[i]])
763 {
764 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
765 return;
766 }
767
768 d = (uint8_t **) d[(size_t) a[i]];
769 }
770
771 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
772
773 if (s > 0)
774 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
775
776 else if (s == 0)
777 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
778 // else a map to an ip pool index.
779 }
780
781 static void uncache_ipmap(in_addr_t ip)
782 {
783 cache_ipmap(ip, 0); // Assign it to the NULL session.
784 }
785
786 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
787 {
788 int i;
789 int bytes;
790 struct ipv6radix *curnode;
791 char ipv6addr[INET6_ADDRSTRLEN];
792
793 curnode = &ipv6_hash[ip.s6_addr[0]];
794
795 bytes = prefixlen >> 3;
796 i = 1;
797 while (i < bytes) {
798 if (curnode->branch == NULL)
799 {
800 if (!(curnode->branch = calloc(256,
801 sizeof (struct ipv6radix))))
802 return;
803 }
804 curnode = &curnode->branch[ip.s6_addr[i]];
805 i++;
806 }
807
808 curnode->sess = s;
809
810 if (s > 0)
811 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
812 inet_ntop(AF_INET6, &ip, ipv6addr,
813 INET6_ADDRSTRLEN),
814 prefixlen);
815 else if (s == 0)
816 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
817 inet_ntop(AF_INET6, &ip, ipv6addr,
818 INET6_ADDRSTRLEN),
819 prefixlen);
820 }
821
822 //
823 // CLI list to dump current ipcache.
824 //
825 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
826 {
827 char **d = (char **) ip_hash, **e, **f, **g;
828 int i, j, k, l;
829 int count = 0;
830
831 if (CLI_HELP_REQUESTED)
832 return CLI_HELP_NO_ARGS;
833
834 cli_print(cli, "%7s %s", "Sess#", "IP Address");
835
836 for (i = 0; i < 256; ++i)
837 {
838 if (!d[i])
839 continue;
840 e = (char **) d[i];
841 for (j = 0; j < 256; ++j)
842 {
843 if (!e[j])
844 continue;
845 f = (char **) e[j];
846 for (k = 0; k < 256; ++k)
847 {
848 if (!f[k])
849 continue;
850 g = (char **)f[k];
851 for (l = 0; l < 256; ++l)
852 {
853 if (!g[l])
854 continue;
855 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
856 ++count;
857 }
858 }
859 }
860 }
861 cli_print(cli, "%d entries in cache", count);
862 return CLI_OK;
863 }
864
865
866 // Find session by username, 0 for not found
867 // walled garden users aren't authenticated, so the username is
868 // reasonably useless. Ignore them to avoid incorrect actions
869 //
870 // This is VERY inefficent. Don't call it often. :)
871 //
872 sessionidt sessionbyuser(char *username)
873 {
874 int s;
875 CSTAT(sessionbyuser);
876
877 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
878 {
879 if (!session[s].opened)
880 continue;
881
882 if (session[s].walled_garden)
883 continue; // Skip walled garden users.
884
885 if (!strncmp(session[s].user, username, 128))
886 return s;
887
888 }
889 return 0; // Not found.
890 }
891
892 void send_garp(in_addr_t ip)
893 {
894 int s;
895 struct ifreq ifr;
896 uint8_t mac[6];
897
898 s = socket(PF_INET, SOCK_DGRAM, 0);
899 if (s < 0)
900 {
901 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
902 return;
903 }
904 memset(&ifr, 0, sizeof(ifr));
905 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
906 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
907 {
908 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
909 close(s);
910 return;
911 }
912 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
913 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
914 {
915 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
916 close(s);
917 return;
918 }
919 close(s);
920 sendarp(ifr.ifr_ifindex, mac, ip);
921 }
922
923 static sessiont *sessiontbysessionidt(sessionidt s)
924 {
925 if (!s || s >= MAXSESSION) return NULL;
926 return &session[s];
927 }
928
929 static sessionidt sessionidtbysessiont(sessiont *s)
930 {
931 sessionidt val = s-session;
932 if (s < session || val >= MAXSESSION) return 0;
933 return val;
934 }
935
936 // actually send a control message for a specific tunnel
937 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
938 {
939 struct sockaddr_in addr;
940
941 CSTAT(tunnelsend);
942
943 if (!t)
944 {
945 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
946 STAT(tunnel_tx_errors);
947 return;
948 }
949
950 if (!tunnel[t].ip)
951 {
952 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
953 STAT(tunnel_tx_errors);
954 return;
955 }
956
957 memset(&addr, 0, sizeof(addr));
958 addr.sin_family = AF_INET;
959 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
960 addr.sin_port = htons(tunnel[t].port);
961
962 // sequence expected, if sequence in message
963 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
964
965 // If this is a control message, deal with retries
966 if (*buf & 0x80)
967 {
968 tunnel[t].last = time_now; // control message sent
969 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
970 if (tunnel[t].try)
971 {
972 STAT(tunnel_retries);
973 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
974 }
975 }
976
977 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
978 {
979 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
980 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
981 STAT(tunnel_tx_errors);
982 return;
983 }
984
985 LOG_HEX(5, "Send Tunnel Data", buf, l);
986 STAT(tunnel_tx_packets);
987 INC_STAT(tunnel_tx_bytes, l);
988 }
989
990 //
991 // Tiny helper function to write data to
992 // the 'tun' device.
993 //
994 int tun_write(uint8_t * data, int size)
995 {
996 return write(tunfd, data, size);
997 }
998
999 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
1000 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
1001 {
1002 int d = (tcp[12] >> 4) * 4;
1003 uint8_t *mss = 0;
1004 uint8_t *opts;
1005 uint8_t *data;
1006 uint16_t orig;
1007 uint32_t sum;
1008
1009 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1010 return;
1011
1012 if (tcp + d > buf + len) // short?
1013 return;
1014
1015 opts = tcp + 20;
1016 data = tcp + d;
1017
1018 while (opts < data)
1019 {
1020 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1021 {
1022 mss = opts + 2;
1023 if (mss + 2 > data) return; // short?
1024 break;
1025 }
1026
1027 if (*opts == 0) return; // end of options
1028 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1029 opts++;
1030 else
1031 opts += opts[1]; // skip over option
1032 }
1033
1034 if (!mss) return; // not found
1035 orig = ntohs(*(uint16_t *) mss);
1036
1037 if (orig <= MSS) return; // mss OK
1038
1039 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1040 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1041 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1042 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1043
1044 // set mss
1045 *(int16_t *) mss = htons(MSS);
1046
1047 // adjust checksum (see rfc1141)
1048 sum = orig + (~MSS & 0xffff);
1049 sum += ntohs(*(uint16_t *) (tcp + 16));
1050 sum = (sum & 0xffff) + (sum >> 16);
1051 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1052 }
1053
1054 // process outgoing (to tunnel) IP
1055 //
1056 static void processipout(uint8_t *buf, int len)
1057 {
1058 sessionidt s;
1059 sessiont *sp;
1060 tunnelidt t;
1061 in_addr_t ip;
1062
1063 uint8_t *data = buf; // Keep a copy of the originals.
1064 int size = len;
1065
1066 uint8_t b[MAXETHER + 20];
1067
1068 CSTAT(processipout);
1069
1070 if (len < MIN_IP_SIZE)
1071 {
1072 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1073 STAT(tun_rx_errors);
1074 return;
1075 }
1076 if (len >= MAXETHER)
1077 {
1078 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1079 STAT(tun_rx_errors);
1080 return;
1081 }
1082
1083 // Skip the tun header
1084 buf += 4;
1085 len -= 4;
1086
1087 // Got an IP header now
1088 if (*(uint8_t *)(buf) >> 4 != 4)
1089 {
1090 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1091 return;
1092 }
1093
1094 ip = *(uint32_t *)(buf + 16);
1095 if (!(s = sessionbyip(ip)))
1096 {
1097 // Is this a packet for a session that doesn't exist?
1098 static int rate = 0; // Number of ICMP packets we've sent this second.
1099 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1100
1101 if (last != time_now)
1102 {
1103 last = time_now;
1104 rate = 0;
1105 }
1106
1107 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1108 {
1109 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1110 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1111 config->bind_address ? config->bind_address : my_address, buf, len);
1112 }
1113 return;
1114 }
1115 t = session[s].tunnel;
1116 sp = &session[s];
1117
1118 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1119 if (config->max_packets > 0)
1120 {
1121 if (sess_local[s].last_packet_out == TIME)
1122 {
1123 int max = config->max_packets;
1124
1125 // All packets for throttled sessions are handled by the
1126 // master, so further limit by using the throttle rate.
1127 // A bit of a kludge, since throttle rate is in kbps,
1128 // but should still be generous given our average DSL
1129 // packet size is 200 bytes: a limit of 28kbps equates
1130 // to around 180 packets per second.
1131 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1132 max = sp->throttle_out;
1133
1134 if (++sess_local[s].packets_out > max)
1135 {
1136 sess_local[s].packets_dropped++;
1137 return;
1138 }
1139 }
1140 else
1141 {
1142 if (sess_local[s].packets_dropped)
1143 {
1144 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1145 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1146 sess_local[s].packets_dropped, sess_local[s].packets_out,
1147 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1148 sp->user);
1149 }
1150
1151 sess_local[s].last_packet_out = TIME;
1152 sess_local[s].packets_out = 1;
1153 sess_local[s].packets_dropped = 0;
1154 }
1155 }
1156
1157 // run access-list if any
1158 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1159 return;
1160
1161 // adjust MSS on SYN and SYN,ACK packets with options
1162 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1163 {
1164 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1165 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1166 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1167 }
1168
1169 if (sp->tbf_out)
1170 {
1171 // Are we throttling this session?
1172 if (config->cluster_iam_master)
1173 tbf_queue_packet(sp->tbf_out, data, size);
1174 else
1175 master_throttle_packet(sp->tbf_out, data, size);
1176 return;
1177 }
1178
1179 if (sp->walled_garden && !config->cluster_iam_master)
1180 {
1181 // We are walled-gardening this
1182 master_garden_packet(s, data, size);
1183 return;
1184 }
1185
1186 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1187
1188 // Add on L2TP header
1189 {
1190 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1191 if (!p) return;
1192 tunnelsend(b, len + (p-b), t); // send it...
1193 }
1194
1195 // Snooping this session, send it to intercept box
1196 if (sp->snoop_ip && sp->snoop_port)
1197 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1198
1199 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1200 sp->cout_delta += len;
1201 sp->pout++;
1202 udp_tx += len;
1203
1204 sess_local[s].cout += len; // To send to master..
1205 sess_local[s].pout++;
1206 }
1207
1208 // process outgoing (to tunnel) IPv6
1209 //
1210 static void processipv6out(uint8_t * buf, int len)
1211 {
1212 sessionidt s;
1213 sessiont *sp;
1214 tunnelidt t;
1215 in_addr_t ip;
1216 struct in6_addr ip6;
1217
1218 uint8_t *data = buf; // Keep a copy of the originals.
1219 int size = len;
1220
1221 uint8_t b[MAXETHER + 20];
1222
1223 CSTAT(processipv6out);
1224
1225 if (len < MIN_IP_SIZE)
1226 {
1227 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1228 STAT(tunnel_tx_errors);
1229 return;
1230 }
1231 if (len >= MAXETHER)
1232 {
1233 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1234 STAT(tunnel_tx_errors);
1235 return;
1236 }
1237
1238 // Skip the tun header
1239 buf += 4;
1240 len -= 4;
1241
1242 // Got an IP header now
1243 if (*(uint8_t *)(buf) >> 4 != 6)
1244 {
1245 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1246 return;
1247 }
1248
1249 ip6 = *(struct in6_addr *)(buf+24);
1250 s = sessionbyipv6(ip6);
1251
1252 if (s == 0)
1253 {
1254 ip = *(uint32_t *)(buf + 32);
1255 s = sessionbyip(ip);
1256 }
1257
1258 if (s == 0)
1259 {
1260 // Is this a packet for a session that doesn't exist?
1261 static int rate = 0; // Number of ICMP packets we've sent this second.
1262 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1263
1264 if (last != time_now)
1265 {
1266 last = time_now;
1267 rate = 0;
1268 }
1269
1270 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1271 {
1272 // FIXME: Should send icmp6 host unreachable
1273 }
1274 return;
1275 }
1276 t = session[s].tunnel;
1277 sp = &session[s];
1278
1279 // FIXME: add DoS prevention/filters?
1280
1281 if (sp->tbf_out)
1282 {
1283 // Are we throttling this session?
1284 if (config->cluster_iam_master)
1285 tbf_queue_packet(sp->tbf_out, data, size);
1286 else
1287 master_throttle_packet(sp->tbf_out, data, size);
1288 return;
1289 }
1290 else if (sp->walled_garden && !config->cluster_iam_master)
1291 {
1292 // We are walled-gardening this
1293 master_garden_packet(s, data, size);
1294 return;
1295 }
1296
1297 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1298
1299 // Add on L2TP header
1300 {
1301 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1302 if (!p) return;
1303 tunnelsend(b, len + (p-b), t); // send it...
1304 }
1305
1306 // Snooping this session, send it to intercept box
1307 if (sp->snoop_ip && sp->snoop_port)
1308 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1309
1310 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1311 sp->cout_delta += len;
1312 sp->pout++;
1313 udp_tx += len;
1314
1315 sess_local[s].cout += len; // To send to master..
1316 sess_local[s].pout++;
1317 }
1318
1319 //
1320 // Helper routine for the TBF filters.
1321 // Used to send queued data in to the user!
1322 //
1323 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1324 {
1325 sessiont *sp;
1326 tunnelidt t;
1327 in_addr_t ip;
1328
1329 uint8_t b[MAXETHER + 20];
1330
1331 if (len < 0 || len > MAXETHER)
1332 {
1333 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1334 return;
1335 }
1336
1337 // Skip the tun header
1338 buf += 4;
1339 len -= 4;
1340
1341 ip = *(in_addr_t *)(buf + 16);
1342
1343 if (!session[s].ip)
1344 return;
1345
1346 t = session[s].tunnel;
1347 sp = &session[s];
1348
1349 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1350
1351 // Add on L2TP header
1352 {
1353 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1354 if (!p) return;
1355 tunnelsend(b, len + (p-b), t); // send it...
1356 }
1357
1358 // Snooping this session.
1359 if (sp->snoop_ip && sp->snoop_port)
1360 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1361
1362 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1363 sp->cout_delta += len;
1364 sp->pout++;
1365 udp_tx += len;
1366
1367 sess_local[s].cout += len; // To send to master..
1368 sess_local[s].pout++;
1369 }
1370
1371 // add an AVP (16 bit)
1372 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1373 {
1374 uint16_t l = (m ? 0x8008 : 0x0008);
1375 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1376 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1377 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1378 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1379 c->length += 8;
1380 }
1381
1382 // add an AVP (32 bit)
1383 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1384 {
1385 uint16_t l = (m ? 0x800A : 0x000A);
1386 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1387 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1388 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1389 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1390 c->length += 10;
1391 }
1392
1393 // add an AVP (string)
1394 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1395 {
1396 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1397 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1398 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1399 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1400 memcpy(c->buf + c->length + 6, val, strlen(val));
1401 c->length += 6 + strlen(val);
1402 }
1403
1404 // add a binary AVP
1405 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1406 {
1407 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1408 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1409 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1410 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1411 memcpy(c->buf + c->length + 6, val, len);
1412 c->length += 6 + len;
1413 }
1414
1415 // new control connection
1416 static controlt *controlnew(uint16_t mtype)
1417 {
1418 controlt *c;
1419 if (!controlfree)
1420 c = malloc(sizeof(controlt));
1421 else
1422 {
1423 c = controlfree;
1424 controlfree = c->next;
1425 }
1426 assert(c);
1427 c->next = 0;
1428 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1429 c->length = 12;
1430 control16(c, 0, mtype, 1);
1431 return c;
1432 }
1433
1434 // send zero block if nothing is waiting
1435 // (ZLB send).
1436 static void controlnull(tunnelidt t)
1437 {
1438 uint8_t buf[12];
1439 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1440 return;
1441
1442 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1443 *(uint16_t *) (buf + 2) = htons(12); // length
1444 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1445 *(uint16_t *) (buf + 6) = htons(0); // session
1446 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1447 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1448 tunnelsend(buf, 12, t);
1449 }
1450
1451 // add a control message to a tunnel, and send if within window
1452 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1453 {
1454 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1455 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1456 *(uint16_t *) (c->buf + 6) = htons(far); // session
1457 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1458 tunnel[t].ns++; // advance sequence
1459 // link in message in to queue
1460 if (tunnel[t].controlc)
1461 tunnel[t].controle->next = c;
1462 else
1463 tunnel[t].controls = c;
1464
1465 tunnel[t].controle = c;
1466 tunnel[t].controlc++;
1467
1468 // send now if space in window
1469 if (tunnel[t].controlc <= tunnel[t].window)
1470 {
1471 tunnel[t].try = 0; // first send
1472 tunnelsend(c->buf, c->length, t);
1473 }
1474 }
1475
1476 //
1477 // Throttle or Unthrottle a session
1478 //
1479 // Throttle the data from/to through a session to no more than
1480 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1481 // user).
1482 //
1483 // If either value is -1, the current value is retained for that
1484 // direction.
1485 //
1486 void throttle_session(sessionidt s, int rate_in, int rate_out)
1487 {
1488 if (!session[s].opened)
1489 return; // No-one home.
1490
1491 if (!*session[s].user)
1492 return; // User not logged in
1493
1494 if (rate_in >= 0)
1495 {
1496 int bytes = rate_in * 1024 / 8; // kbits to bytes
1497 if (session[s].tbf_in)
1498 free_tbf(session[s].tbf_in);
1499
1500 if (rate_in > 0)
1501 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1502 else
1503 session[s].tbf_in = 0;
1504
1505 session[s].throttle_in = rate_in;
1506 }
1507
1508 if (rate_out >= 0)
1509 {
1510 int bytes = rate_out * 1024 / 8;
1511 if (session[s].tbf_out)
1512 free_tbf(session[s].tbf_out);
1513
1514 if (rate_out > 0)
1515 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1516 else
1517 session[s].tbf_out = 0;
1518
1519 session[s].throttle_out = rate_out;
1520 }
1521 }
1522
1523 // add/remove filters from session (-1 = no change)
1524 void filter_session(sessionidt s, int filter_in, int filter_out)
1525 {
1526 if (!session[s].opened)
1527 return; // No-one home.
1528
1529 if (!*session[s].user)
1530 return; // User not logged in
1531
1532 // paranoia
1533 if (filter_in > MAXFILTER) filter_in = -1;
1534 if (filter_out > MAXFILTER) filter_out = -1;
1535 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1536 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1537
1538 if (filter_in >= 0)
1539 {
1540 if (session[s].filter_in)
1541 ip_filters[session[s].filter_in - 1].used--;
1542
1543 if (filter_in > 0)
1544 ip_filters[filter_in - 1].used++;
1545
1546 session[s].filter_in = filter_in;
1547 }
1548
1549 if (filter_out >= 0)
1550 {
1551 if (session[s].filter_out)
1552 ip_filters[session[s].filter_out - 1].used--;
1553
1554 if (filter_out > 0)
1555 ip_filters[filter_out - 1].used++;
1556
1557 session[s].filter_out = filter_out;
1558 }
1559 }
1560
1561 // start tidy shutdown of session
1562 void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause)
1563 {
1564 int walled_garden = session[s].walled_garden;
1565
1566
1567 CSTAT(sessionshutdown);
1568
1569 if (!session[s].opened)
1570 {
1571 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1572 return; // not a live session
1573 }
1574
1575 if (!session[s].die)
1576 {
1577 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1578 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1579 run_plugins(PLUGIN_KILL_SESSION, &data);
1580 }
1581
1582 if (session[s].ip && !walled_garden && !session[s].die)
1583 {
1584 // RADIUS Stop message
1585 uint16_t r = radiusnew(s);
1586 if (r)
1587 {
1588 // stop, if not already trying
1589 if (radius[r].state != RADIUSSTOP)
1590 {
1591 radius[r].term_cause = term_cause;
1592 radius[r].term_msg = reason;
1593 radiussend(r, RADIUSSTOP);
1594 }
1595 }
1596 else
1597 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1598
1599 // Save counters to dump to accounting file
1600 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1601 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1602 }
1603
1604 if (session[s].ip)
1605 { // IP allocated, clear and unroute
1606 int r;
1607 int routed = 0;
1608 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1609 {
1610 if ((session[s].ip & session[s].route[r].mask) ==
1611 (session[s].route[r].ip & session[s].route[r].mask))
1612 routed++;
1613
1614 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1615 session[s].route[r].ip = 0;
1616 }
1617
1618 if (session[s].ip_pool_index == -1) // static ip
1619 {
1620 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1621 session[s].ip = 0;
1622 }
1623 else
1624 free_ip_address(s);
1625
1626 // unroute IPv6, if setup
1627 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1628 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1629 }
1630
1631 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1632 throttle_session(s, 0, 0);
1633
1634 if (cdn_result)
1635 { // Send CDN
1636 controlt *c = controlnew(14); // sending CDN
1637 if (cdn_error)
1638 {
1639 uint8_t buf[4];
1640 *(uint16_t *) buf = htons(cdn_result);
1641 *(uint16_t *) (buf+2) = htons(cdn_error);
1642 controlb(c, 1, buf, 4, 1);
1643 }
1644 else
1645 control16(c, 1, cdn_result, 1);
1646
1647 control16(c, 14, s, 1); // assigned session (our end)
1648 controladd(c, session[s].far, session[s].tunnel); // send the message
1649 }
1650
1651 if (!session[s].die)
1652 session[s].die = TIME + 150; // Clean up in 15 seconds
1653
1654 // update filter refcounts
1655 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1656 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1657
1658 // clear PPP state
1659 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1660 sess_local[s].lcp.restart = 0;
1661 sess_local[s].ipcp.restart = 0;
1662 sess_local[s].ipv6cp.restart = 0;
1663 sess_local[s].ccp.restart = 0;
1664
1665 cluster_send_session(s);
1666 }
1667
1668 void sendipcp(sessionidt s, tunnelidt t)
1669 {
1670 uint8_t buf[MAXETHER];
1671 uint8_t *q;
1672
1673 CSTAT(sendipcp);
1674 LOG(3, s, t, "IPCP: send ConfigReq\n");
1675
1676 if (!session[s].unique_id)
1677 {
1678 if (!++last_id) ++last_id; // skip zero
1679 session[s].unique_id = last_id;
1680 }
1681
1682 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP);
1683 if (!q) return;
1684
1685 *q = ConfigReq;
1686 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1687 *(uint16_t *) (q + 2) = htons(10); // packet length
1688 q[4] = 3; // ip address option
1689 q[5] = 6; // option length
1690 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1691 config->bind_address ? config->bind_address :
1692 my_address; // send my IP
1693
1694 tunnelsend(buf, 10 + (q - buf), t); // send it
1695 restart_timer(s, ipcp);
1696 }
1697
1698 void sendipv6cp(sessionidt s, tunnelidt t)
1699 {
1700 uint8_t buf[MAXETHER];
1701 uint8_t *q;
1702
1703 CSTAT(sendipv6cp);
1704 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1705
1706 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1707 if (!q) return;
1708
1709 *q = ConfigReq;
1710 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1711 // only send one type
1712 // of request
1713 *(uint16_t *) (q + 2) = htons(14);
1714 q[4] = 1; // interface identifier option
1715 q[5] = 10; // option length
1716 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1717 *(uint32_t *) (q + 10) = 0;
1718 q[13] = 1;
1719
1720 tunnelsend(buf, 14 + (q - buf), t); // send it
1721 restart_timer(s, ipv6cp);
1722 }
1723
1724 static void sessionclear(sessionidt s)
1725 {
1726 memset(&session[s], 0, sizeof(session[s]));
1727 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1728 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1729
1730 session[s].tunnel = T_FREE; // Mark it as free.
1731 session[s].next = sessionfree;
1732 sessionfree = s;
1733 }
1734
1735 // kill a session now
1736 void sessionkill(sessionidt s, char *reason)
1737 {
1738
1739 CSTAT(sessionkill);
1740
1741 if (!session[s].opened) // not alive
1742 return;
1743
1744 if (session[s].next)
1745 {
1746 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1747 return;
1748 }
1749
1750 session[s].die = TIME;
1751 sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
1752 if (sess_local[s].radius)
1753 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1754
1755 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1756 sessionclear(s);
1757 cluster_send_session(s);
1758 }
1759
1760 static void tunnelclear(tunnelidt t)
1761 {
1762 if (!t) return;
1763 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1764 tunnel[t].state = TUNNELFREE;
1765 }
1766
1767 // kill a tunnel now
1768 static void tunnelkill(tunnelidt t, char *reason)
1769 {
1770 sessionidt s;
1771 controlt *c;
1772
1773 CSTAT(tunnelkill);
1774
1775 tunnel[t].state = TUNNELDIE;
1776
1777 // free control messages
1778 while ((c = tunnel[t].controls))
1779 {
1780 controlt * n = c->next;
1781 tunnel[t].controls = n;
1782 tunnel[t].controlc--;
1783 c->next = controlfree;
1784 controlfree = c;
1785 }
1786 // kill sessions
1787 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1788 if (session[s].tunnel == t)
1789 sessionkill(s, reason);
1790
1791 // free tunnel
1792 tunnelclear(t);
1793 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1794 cli_tunnel_actions[t].action = 0;
1795 cluster_send_tunnel(t);
1796 }
1797
1798 // shut down a tunnel cleanly
1799 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1800 {
1801 sessionidt s;
1802
1803 CSTAT(tunnelshutdown);
1804
1805 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1806 {
1807 // never set up, can immediately kill
1808 tunnelkill(t, reason);
1809 return;
1810 }
1811 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1812
1813 // close session
1814 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1815 if (session[s].tunnel == t)
1816 sessionshutdown(s, reason, CDN_NONE, TERM_ADMIN_RESET);
1817
1818 tunnel[t].state = TUNNELDIE;
1819 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1820 cluster_send_tunnel(t);
1821 // TBA - should we wait for sessions to stop?
1822 if (result)
1823 {
1824 controlt *c = controlnew(4); // sending StopCCN
1825 if (error)
1826 {
1827 uint8_t buf[64];
1828 int l = 4;
1829 *(uint16_t *) buf = htons(result);
1830 *(uint16_t *) (buf+2) = htons(error);
1831 if (msg)
1832 {
1833 int m = strlen(msg);
1834 if (m + 4 > sizeof(buf))
1835 m = sizeof(buf) - 4;
1836
1837 memcpy(buf+4, msg, m);
1838 l += m;
1839 }
1840
1841 controlb(c, 1, buf, l, 1);
1842 }
1843 else
1844 control16(c, 1, result, 1);
1845
1846 control16(c, 9, t, 1); // assigned tunnel (our end)
1847 controladd(c, 0, t); // send the message
1848 }
1849 }
1850
1851 // read and process packet on tunnel (UDP)
1852 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1853 {
1854 uint8_t *chapresponse = NULL;
1855 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1856 uint8_t *p = buf + 2;
1857
1858
1859 CSTAT(processudp);
1860
1861 udp_rx += len;
1862 udp_rx_pkt++;
1863 LOG_HEX(5, "UDP Data", buf, len);
1864 STAT(tunnel_rx_packets);
1865 INC_STAT(tunnel_rx_bytes, len);
1866 if (len < 6)
1867 {
1868 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1869 STAT(tunnel_rx_errors);
1870 return;
1871 }
1872 if ((buf[1] & 0x0F) != 2)
1873 {
1874 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1875 STAT(tunnel_rx_errors);
1876 return;
1877 }
1878 if (*buf & 0x40)
1879 { // length
1880 l = ntohs(*(uint16_t *) p);
1881 p += 2;
1882 }
1883 t = ntohs(*(uint16_t *) p);
1884 p += 2;
1885 s = ntohs(*(uint16_t *) p);
1886 p += 2;
1887 if (s >= MAXSESSION)
1888 {
1889 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1890 STAT(tunnel_rx_errors);
1891 return;
1892 }
1893 if (t >= MAXTUNNEL)
1894 {
1895 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1896 STAT(tunnel_rx_errors);
1897 return;
1898 }
1899 if (*buf & 0x08)
1900 { // ns/nr
1901 ns = ntohs(*(uint16_t *) p);
1902 p += 2;
1903 nr = ntohs(*(uint16_t *) p);
1904 p += 2;
1905 }
1906 if (*buf & 0x02)
1907 { // offset
1908 uint16_t o = ntohs(*(uint16_t *) p);
1909 p += o + 2;
1910 }
1911 if ((p - buf) > l)
1912 {
1913 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1914 STAT(tunnel_rx_errors);
1915 return;
1916 }
1917 l -= (p - buf);
1918
1919 // used to time out old tunnels
1920 if (t && tunnel[t].state == TUNNELOPEN)
1921 tunnel[t].lastrec = time_now;
1922
1923 if (*buf & 0x80)
1924 { // control
1925 uint16_t message = 0xFFFF; // message type
1926 uint8_t fatal = 0;
1927 uint8_t mandatory = 0;
1928 uint16_t asession = 0; // assigned session
1929 uint32_t amagic = 0; // magic number
1930 uint8_t aflags = 0; // flags from last LCF
1931 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1932 char called[MAXTEL] = ""; // called number
1933 char calling[MAXTEL] = ""; // calling number
1934
1935 if (!config->cluster_iam_master)
1936 {
1937 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1938 return;
1939 }
1940
1941 // control messages must have bits 0x80|0x40|0x08
1942 // (type, length and sequence) set, and bits 0x02|0x01
1943 // (offset and priority) clear
1944 if ((*buf & 0xCB) != 0xC8)
1945 {
1946 LOG(1, s, t, "Bad control header %02X\n", *buf);
1947 STAT(tunnel_rx_errors);
1948 return;
1949 }
1950
1951 // check for duplicate tunnel open message
1952 if (!t && ns == 0)
1953 {
1954 int i;
1955
1956 //
1957 // Is this a duplicate of the first packet? (SCCRQ)
1958 //
1959 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1960 {
1961 if (tunnel[i].state != TUNNELOPENING ||
1962 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1963 tunnel[i].port != ntohs(addr->sin_port) )
1964 continue;
1965 t = i;
1966 LOG(3, s, t, "Duplicate SCCRQ?\n");
1967 break;
1968 }
1969 }
1970
1971 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1972 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1973
1974 // if no tunnel specified, assign one
1975 if (!t)
1976 {
1977 if (!(t = new_tunnel()))
1978 {
1979 LOG(1, 0, 0, "No more tunnels\n");
1980 STAT(tunnel_overflow);
1981 return;
1982 }
1983 tunnelclear(t);
1984 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1985 tunnel[t].port = ntohs(addr->sin_port);
1986 tunnel[t].window = 4; // default window
1987 STAT(tunnel_created);
1988 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1989 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1990 }
1991
1992 // If the 'ns' just received is not the 'nr' we're
1993 // expecting, just send an ack and drop it.
1994 //
1995 // if 'ns' is less, then we got a retransmitted packet.
1996 // if 'ns' is greater than missed a packet. Either way
1997 // we should ignore it.
1998 if (ns != tunnel[t].nr)
1999 {
2000 // is this the sequence we were expecting?
2001 STAT(tunnel_rx_errors);
2002 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
2003 t, ns, tunnel[t].nr);
2004
2005 if (l) // Is this not a ZLB?
2006 controlnull(t);
2007 return;
2008 }
2009
2010 // check sequence of this message
2011 {
2012 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2013 // some to clear maybe?
2014 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2015 {
2016 controlt *c = tunnel[t].controls;
2017 tunnel[t].controls = c->next;
2018 tunnel[t].controlc--;
2019 c->next = controlfree;
2020 controlfree = c;
2021 skip--;
2022 tunnel[t].try = 0; // we have progress
2023 }
2024
2025 // receiver advance (do here so quoted correctly in any sends below)
2026 if (l) tunnel[t].nr = (ns + 1);
2027 if (skip < 0) skip = 0;
2028 if (skip < tunnel[t].controlc)
2029 {
2030 // some control packets can now be sent that were previous stuck out of window
2031 int tosend = tunnel[t].window - skip;
2032 controlt *c = tunnel[t].controls;
2033 while (c && skip)
2034 {
2035 c = c->next;
2036 skip--;
2037 }
2038 while (c && tosend)
2039 {
2040 tunnel[t].try = 0; // first send
2041 tunnelsend(c->buf, c->length, t);
2042 c = c->next;
2043 tosend--;
2044 }
2045 }
2046 if (!tunnel[t].controlc)
2047 tunnel[t].retry = 0; // caught up
2048 }
2049 if (l)
2050 { // if not a null message
2051 int result = 0;
2052 int error = 0;
2053 char *msg = 0;
2054
2055 // default disconnect cause/message on receipt
2056 // of CDN (set to more specific value from
2057 // attribute 46 if present below).
2058 int disc_cause = TERM_NAS_REQUEST;
2059 char const *disc_reason = "Closed (Received CDN).";
2060
2061 // process AVPs
2062 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2063 {
2064 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2065 uint8_t *b = p;
2066 uint8_t flags = *p;
2067 uint16_t mtype;
2068
2069 if (n > l)
2070 {
2071 LOG(1, s, t, "Invalid length in AVP\n");
2072 STAT(tunnel_rx_errors);
2073 return;
2074 }
2075 p += n; // next
2076 l -= n;
2077 if (flags & 0x3C) // reserved bits, should be clear
2078 {
2079 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2080 fatal = flags;
2081 result = 2; // general error
2082 error = 3; // reserved field non-zero
2083 msg = 0;
2084 continue; // next
2085 }
2086 b += 2;
2087 if (*(uint16_t *) (b))
2088 {
2089 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
2090 fatal = flags;
2091 result = 2; // general error
2092 error = 6; // generic vendor-specific error
2093 msg = "unsupported vendor-specific";
2094 continue; // next
2095 }
2096 b += 2;
2097 mtype = ntohs(*(uint16_t *) (b));
2098 b += 2;
2099 n -= 6;
2100
2101 if (flags & 0x40)
2102 {
2103 uint16_t orig_len;
2104
2105 // handle hidden AVPs
2106 if (!*config->l2tp_secret)
2107 {
2108 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2109 fatal = flags;
2110 result = 2; // general error
2111 error = 6; // generic vendor-specific error
2112 msg = "secret not specified";
2113 continue;
2114 }
2115 if (!session[s].random_vector_length)
2116 {
2117 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2118 fatal = flags;
2119 result = 2; // general error
2120 error = 6; // generic
2121 msg = "no random vector";
2122 continue;
2123 }
2124 if (n < 8)
2125 {
2126 LOG(2, s, t, "Short hidden AVP.\n");
2127 fatal = flags;
2128 result = 2; // general error
2129 error = 2; // length is wrong
2130 msg = 0;
2131 continue;
2132 }
2133
2134 // Unhide the AVP
2135 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2136
2137 orig_len = ntohs(*(uint16_t *) b);
2138 if (orig_len > n + 2)
2139 {
2140 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2141 orig_len, n);
2142
2143 fatal = flags;
2144 result = 2; // general error
2145 error = 2; // length is wrong
2146 msg = 0;
2147 continue;
2148 }
2149
2150 b += 2;
2151 n = orig_len;
2152 }
2153
2154 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2155 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2156
2157 switch (mtype)
2158 {
2159 case 0: // message type
2160 message = ntohs(*(uint16_t *) b);
2161 mandatory = flags & 0x80;
2162 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2163 break;
2164 case 1: // result code
2165 {
2166 uint16_t rescode = ntohs(*(uint16_t *) b);
2167 const char* resdesc = "(unknown)";
2168 if (message == 4)
2169 { /* StopCCN */
2170 resdesc = l2tp_stopccn_result_code(rescode);
2171 }
2172 else if (message == 14)
2173 { /* CDN */
2174 resdesc = l2tp_cdn_result_code(rescode);
2175 }
2176
2177 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2178 if (n >= 4)
2179 {
2180 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2181 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2182 }
2183 if (n > 4)
2184 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2185
2186 break;
2187 }
2188 break;
2189 case 2: // protocol version
2190 {
2191 version = ntohs(*(uint16_t *) (b));
2192 LOG(4, s, t, " Protocol version = %d\n", version);
2193 if (version && version != 0x0100)
2194 { // allow 0.0 and 1.0
2195 LOG(1, s, t, " Bad protocol version %04X\n", version);
2196 fatal = flags;
2197 result = 5; // unspported protocol version
2198 error = 0x0100; // supported version
2199 msg = 0;
2200 continue; // next
2201 }
2202 }
2203 break;
2204 case 3: // framing capabilities
2205 break;
2206 case 4: // bearer capabilities
2207 break;
2208 case 5: // tie breaker
2209 // We never open tunnels, so we don't care about tie breakers
2210 continue;
2211 case 6: // firmware revision
2212 break;
2213 case 7: // host name
2214 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2215 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2216 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2217 // TBA - to send to RADIUS
2218 break;
2219 case 8: // vendor name
2220 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2221 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2222 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2223 break;
2224 case 9: // assigned tunnel
2225 tunnel[t].far = ntohs(*(uint16_t *) (b));
2226 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2227 break;
2228 case 10: // rx window
2229 tunnel[t].window = ntohs(*(uint16_t *) (b));
2230 if (!tunnel[t].window)
2231 tunnel[t].window = 1; // window of 0 is silly
2232 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2233 break;
2234 case 11: // Challenge
2235 {
2236 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2237 build_chap_response(b, 2, n, &chapresponse);
2238 }
2239 break;
2240 case 13: // Response
2241 // Why did they send a response? We never challenge.
2242 LOG(2, s, t, " received unexpected challenge response\n");
2243 break;
2244
2245 case 14: // assigned session
2246 asession = session[s].far = ntohs(*(uint16_t *) (b));
2247 LOG(4, s, t, " assigned session = %d\n", asession);
2248 break;
2249 case 15: // call serial number
2250 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2251 break;
2252 case 18: // bearer type
2253 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2254 // TBA - for RADIUS
2255 break;
2256 case 19: // framing type
2257 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2258 // TBA
2259 break;
2260 case 21: // called number
2261 memset(called, 0, sizeof(called));
2262 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2263 LOG(4, s, t, " Called <%s>\n", called);
2264 break;
2265 case 22: // calling number
2266 memset(calling, 0, sizeof(calling));
2267 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2268 LOG(4, s, t, " Calling <%s>\n", calling);
2269 break;
2270 case 23: // subtype
2271 break;
2272 case 24: // tx connect speed
2273 if (n == 4)
2274 {
2275 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2276 }
2277 else
2278 {
2279 // AS5300s send connect speed as a string
2280 char tmp[30];
2281 memset(tmp, 0, sizeof(tmp));
2282 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2283 session[s].tx_connect_speed = atol(tmp);
2284 }
2285 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2286 break;
2287 case 38: // rx connect speed
2288 if (n == 4)
2289 {
2290 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2291 }
2292 else
2293 {
2294 // AS5300s send connect speed as a string
2295 char tmp[30];
2296 memset(tmp, 0, sizeof(tmp));
2297 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2298 session[s].rx_connect_speed = atol(tmp);
2299 }
2300 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2301 break;
2302 case 25: // Physical Channel ID
2303 {
2304 uint32_t tmp = ntohl(*(uint32_t *) b);
2305 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2306 break;
2307 }
2308 case 29: // Proxy Authentication Type
2309 {
2310 uint16_t atype = ntohs(*(uint16_t *)b);
2311 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2312 break;
2313 }
2314 case 30: // Proxy Authentication Name
2315 {
2316 char authname[64];
2317 memset(authname, 0, sizeof(authname));
2318 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2319 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2320 authname);
2321 break;
2322 }
2323 case 31: // Proxy Authentication Challenge
2324 {
2325 LOG(4, s, t, " Proxy Auth Challenge\n");
2326 break;
2327 }
2328 case 32: // Proxy Authentication ID
2329 {
2330 uint16_t authid = ntohs(*(uint16_t *)(b));
2331 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2332 break;
2333 }
2334 case 33: // Proxy Authentication Response
2335 LOG(4, s, t, " Proxy Auth Response\n");
2336 break;
2337 case 27: // last sent lcp
2338 { // find magic number
2339 uint8_t *p = b, *e = p + n;
2340 while (p + 1 < e && p[1] && p + p[1] <= e)
2341 {
2342 if (*p == 5 && p[1] == 6) // Magic-Number
2343 amagic = ntohl(*(uint32_t *) (p + 2));
2344 else if (*p == 7) // Protocol-Field-Compression
2345 aflags |= SESSION_PFC;
2346 else if (*p == 8) // Address-and-Control-Field-Compression
2347 aflags |= SESSION_ACFC;
2348 p += p[1];
2349 }
2350 }
2351 break;
2352 case 28: // last recv lcp confreq
2353 break;
2354 case 26: // Initial Received LCP CONFREQ
2355 break;
2356 case 39: // seq required - we control it as an LNS anyway...
2357 break;
2358 case 36: // Random Vector
2359 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2360 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2361 if (n > sizeof(session[s].random_vector))
2362 n = sizeof(session[s].random_vector);
2363 memcpy(session[s].random_vector, b, n);
2364 session[s].random_vector_length = n;
2365 break;
2366 case 46: // ppp disconnect cause
2367 if (n >= 5)
2368 {
2369 uint16_t code = ntohs(*(uint16_t *) b);
2370 uint16_t proto = ntohs(*(uint16_t *) (b + 2));
2371 uint8_t dir = *(b + 4);
2372
2373 LOG(4, s, t, " PPP disconnect cause "
2374 "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
2375 code, proto, dir, n - 5, b + 5);
2376
2377 switch (code)
2378 {
2379 case 1: // admin disconnect
2380 disc_cause = TERM_ADMIN_RESET;
2381 disc_reason = "Administrative disconnect";
2382 break;
2383 case 3: // lcp terminate
2384 if (dir != 1) break; // 1=peer, 2=local
2385 disc_cause = TERM_USER_REQUEST;
2386 disc_reason = "Normal disconnection";
2387 break;
2388 case 4: // compulsory encryption unavailable
2389 if (dir != 2) break; // 1=refused by peer, 2=local
2390 disc_cause = TERM_USER_ERROR;
2391 disc_reason = "Compulsory encryption refused";
2392 break;
2393 case 5: // lcp: fsm timeout
2394 disc_cause = TERM_PORT_ERROR;
2395 disc_reason = "LCP: FSM timeout";
2396 break;
2397 case 6: // lcp: no recognisable lcp packets received
2398 disc_cause = TERM_PORT_ERROR;
2399 disc_reason = "LCP: no recognisable LCP packets";
2400 break;
2401 case 7: // lcp: magic-no error (possibly looped back)
2402 disc_cause = TERM_PORT_ERROR;
2403 disc_reason = "LCP: magic-no error (possible loop)";
2404 break;
2405 case 8: // lcp: echo request timeout
2406 disc_cause = TERM_PORT_ERROR;
2407 disc_reason = "LCP: echo request timeout";
2408 break;
2409 case 13: // auth: fsm timeout
2410 disc_cause = TERM_SERVICE_UNAVAILABLE;
2411 disc_reason = "Authentication: FSM timeout";
2412 break;
2413 case 15: // auth: unacceptable auth protocol
2414 disc_cause = TERM_SERVICE_UNAVAILABLE;
2415 disc_reason = "Unacceptable authentication protocol";
2416 break;
2417 case 16: // auth: authentication failed
2418 disc_cause = TERM_SERVICE_UNAVAILABLE;
2419 disc_reason = "Authentication failed";
2420 break;
2421 case 17: // ncp: fsm timeout
2422 disc_cause = TERM_SERVICE_UNAVAILABLE;
2423 disc_reason = "NCP: FSM timeout";
2424 break;
2425 case 18: // ncp: no ncps available
2426 disc_cause = TERM_SERVICE_UNAVAILABLE;
2427 disc_reason = "NCP: no NCPs available";
2428 break;
2429 case 19: // ncp: failure to converge on acceptable address
2430 disc_cause = TERM_SERVICE_UNAVAILABLE;
2431 disc_reason = (dir == 1)
2432 ? "NCP: too many Configure-Naks received from peer"
2433 : "NCP: too many Configure-Naks sent to peer";
2434 break;
2435 case 20: // ncp: user not permitted to use any address
2436 disc_cause = TERM_SERVICE_UNAVAILABLE;
2437 disc_reason = (dir == 1)
2438 ? "NCP: local link address not acceptable to peer"
2439 : "NCP: remote link address not acceptable";
2440 break;
2441 }
2442 }
2443 break;
2444 default:
2445 {
2446 static char e[] = "unknown AVP 0xXXXX";
2447 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2448 fatal = flags;
2449 result = 2; // general error
2450 error = 8; // unknown mandatory AVP
2451 sprintf((msg = e) + 14, "%04x", mtype);
2452 continue; // next
2453 }
2454 }
2455 }
2456 // process message
2457 if (fatal & 0x80)
2458 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2459 else
2460 switch (message)
2461 {
2462 case 1: // SCCRQ - Start Control Connection Request
2463 tunnel[t].state = TUNNELOPENING;
2464 if (main_quit != QUIT_SHUTDOWN)
2465 {
2466 controlt *c = controlnew(2); // sending SCCRP
2467 control16(c, 2, version, 1); // protocol version
2468 control32(c, 3, 3, 1); // framing
2469 controls(c, 7, hostname, 1); // host name
2470 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2471 control16(c, 9, t, 1); // assigned tunnel
2472 controladd(c, 0, t); // send the resply
2473 }
2474 else
2475 {
2476 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2477 }
2478 break;
2479 case 2: // SCCRP
2480 tunnel[t].state = TUNNELOPEN;
2481 break;
2482 case 3: // SCCN
2483 tunnel[t].state = TUNNELOPEN;
2484 controlnull(t); // ack
2485 break;
2486 case 4: // StopCCN
2487 controlnull(t); // ack
2488 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2489 break;
2490 case 6: // HELLO
2491 controlnull(t); // simply ACK
2492 break;
2493 case 7: // OCRQ
2494 // TBA
2495 break;
2496 case 8: // OCRO
2497 // TBA
2498 break;
2499 case 9: // OCCN
2500 // TBA
2501 break;
2502 case 10: // ICRQ
2503 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2504 {
2505 controlt *c = controlnew(11); // ICRP
2506
2507 s = sessionfree;
2508 sessionfree = session[s].next;
2509 memset(&session[s], 0, sizeof(session[s]));
2510
2511 if (s > config->cluster_highest_sessionid)
2512 config->cluster_highest_sessionid = s;
2513
2514 session[s].opened = time_now;
2515 session[s].tunnel = t;
2516 session[s].far = asession;
2517 session[s].last_packet = time_now;
2518 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2519 control16(c, 14, s, 1); // assigned session
2520 controladd(c, asession, t); // send the reply
2521
2522 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2523 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2524
2525 session[s].ppp.phase = Establish;
2526 session[s].ppp.lcp = Starting;
2527
2528 STAT(session_created);
2529 break;
2530 }
2531
2532 {
2533 controlt *c = controlnew(14); // CDN
2534 if (!sessionfree)
2535 {
2536 STAT(session_overflow);
2537 LOG(1, 0, t, "No free sessions\n");
2538 control16(c, 1, 4, 0); // temporary lack of resources
2539 }
2540 else
2541 control16(c, 1, 2, 7); // shutting down, try another
2542
2543 controladd(c, asession, t); // send the message
2544 }
2545 return;
2546 case 11: // ICRP
2547 // TBA
2548 break;
2549 case 12: // ICCN
2550 if (amagic == 0) amagic = time_now;
2551 session[s].magic = amagic; // set magic number
2552 session[s].flags = aflags; // set flags received
2553 session[s].mru = PPPoE_MRU; // default
2554 controlnull(t); // ack
2555
2556 // start LCP
2557 sess_local[s].lcp_authtype = config->radius_authprefer;
2558 sess_local[s].ppp_mru = MRU;
2559 sendlcp(s, t);
2560 change_state(s, lcp, RequestSent);
2561 break;
2562
2563 case 14: // CDN
2564 controlnull(t); // ack
2565 sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
2566 break;
2567 case 0xFFFF:
2568 LOG(1, s, t, "Missing message type\n");
2569 break;
2570 default:
2571 STAT(tunnel_rx_errors);
2572 if (mandatory)
2573 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2574 else
2575 LOG(1, s, t, "Unknown message type %d\n", message);
2576 break;
2577 }
2578 if (chapresponse) free(chapresponse);
2579 cluster_send_tunnel(t);
2580 }
2581 else
2582 {
2583 LOG(4, s, t, " Got a ZLB ack\n");
2584 }
2585 }
2586 else
2587 { // data
2588 uint16_t proto;
2589
2590 LOG_HEX(5, "Receive Tunnel Data", p, l);
2591 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2592 { // HDLC address header, discard
2593 p += 2;
2594 l -= 2;
2595 }
2596 if (l < 2)
2597 {
2598 LOG(1, s, t, "Short ppp length %d\n", l);
2599 STAT(tunnel_rx_errors);
2600 return;
2601 }
2602 if (*p & 1)
2603 {
2604 proto = *p++;
2605 l--;
2606 }
2607 else
2608 {
2609 proto = ntohs(*(uint16_t *) p);
2610 p += 2;
2611 l -= 2;
2612 }
2613
2614 if (s && !session[s].opened) // Is something wrong??
2615 {
2616 if (!config->cluster_iam_master)
2617 {
2618 // Pass it off to the master to deal with..
2619 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2620 return;
2621 }
2622
2623
2624 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2625 STAT(tunnel_rx_errors);
2626 return;
2627 }
2628
2629 if (proto == PPPPAP)
2630 {
2631 session[s].last_packet = time_now;
2632 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2633 processpap(s, t, p, l);
2634 }
2635 else if (proto == PPPCHAP)
2636 {
2637 session[s].last_packet = time_now;
2638 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2639 processchap(s, t, p, l);
2640 }
2641 else if (proto == PPPLCP)
2642 {
2643 session[s].last_packet = time_now;
2644 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2645 processlcp(s, t, p, l);
2646 }
2647 else if (proto == PPPIPCP)
2648 {
2649 session[s].last_packet = time_now;
2650 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2651 processipcp(s, t, p, l);
2652 }
2653 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2654 {
2655 session[s].last_packet = time_now;
2656 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2657 processipv6cp(s, t, p, l);
2658 }
2659 else if (proto == PPPCCP)
2660 {
2661 session[s].last_packet = time_now;
2662 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2663 processccp(s, t, p, l);
2664 }
2665 else if (proto == PPPIP)
2666 {
2667 if (session[s].die)
2668 {
2669 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2670 return; // closing session, PPP not processed
2671 }
2672
2673 session[s].last_packet = time_now;
2674 if (session[s].walled_garden && !config->cluster_iam_master)
2675 {
2676 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2677 return;
2678 }
2679
2680 processipin(s, t, p, l);
2681 }
2682 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2683 {
2684 if (session[s].die)
2685 {
2686 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2687 return; // closing session, PPP not processed
2688 }
2689
2690 session[s].last_packet = time_now;
2691 if (session[s].walled_garden && !config->cluster_iam_master)
2692 {
2693 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2694 return;
2695 }
2696
2697 processipv6in(s, t, p, l);
2698 }
2699 else if (session[s].ppp.lcp == Opened)
2700 {
2701 session[s].last_packet = time_now;
2702 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2703 protoreject(s, t, p, l, proto);
2704 }
2705 else
2706 {
2707 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2708 proto, ppp_state(session[s].ppp.lcp));
2709 }
2710 }
2711 }
2712
2713 // read and process packet on tun
2714 static void processtun(uint8_t * buf, int len)
2715 {
2716 LOG_HEX(5, "Receive TUN Data", buf, len);
2717 STAT(tun_rx_packets);
2718 INC_STAT(tun_rx_bytes, len);
2719
2720 CSTAT(processtun);
2721
2722 eth_rx_pkt++;
2723 eth_rx += len;
2724 if (len < 22)
2725 {
2726 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2727 STAT(tun_rx_errors);
2728 return;
2729 }
2730
2731 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2732 processipout(buf, len);
2733 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2734 && config->ipv6_prefix.s6_addr[0])
2735 processipv6out(buf, len);
2736
2737 // Else discard.
2738 }
2739
2740 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2741 // that we look at the whole of the tunnel, radius and session tables
2742 // every second
2743 static void regular_cleanups(double period)
2744 {
2745 // Next tunnel, radius and session to check for actions on.
2746 static tunnelidt t = 0;
2747 static int r = 0;
2748 static sessionidt s = 0;
2749
2750 int t_actions = 0;
2751 int r_actions = 0;
2752 int s_actions = 0;
2753
2754 int t_slice;
2755 int r_slice;
2756 int s_slice;
2757
2758 int i;
2759 int a;
2760
2761 // divide up tables into slices based on the last run
2762 t_slice = config->cluster_highest_tunnelid * period;
2763 r_slice = (MAXRADIUS - 1) * period;
2764 s_slice = config->cluster_highest_sessionid * period;
2765
2766 if (t_slice < 1)
2767 t_slice = 1;
2768 else if (t_slice > config->cluster_highest_tunnelid)
2769 t_slice = config->cluster_highest_tunnelid;
2770
2771 if (r_slice < 1)
2772 r_slice = 1;
2773 else if (r_slice > (MAXRADIUS - 1))
2774 r_slice = MAXRADIUS - 1;
2775
2776 if (s_slice < 1)
2777 s_slice = 1;
2778 else if (s_slice > config->cluster_highest_sessionid)
2779 s_slice = config->cluster_highest_sessionid;
2780
2781 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2782
2783 for (i = 0; i < t_slice; i++)
2784 {
2785 t++;
2786 if (t > config->cluster_highest_tunnelid)
2787 t = 1;
2788
2789 // check for expired tunnels
2790 if (tunnel[t].die && tunnel[t].die <= TIME)
2791 {
2792 STAT(tunnel_timeout);
2793 tunnelkill(t, "Expired");
2794 t_actions++;
2795 continue;
2796 }
2797 // check for message resend
2798 if (tunnel[t].retry && tunnel[t].controlc)
2799 {
2800 // resend pending messages as timeout on reply
2801 if (tunnel[t].retry <= TIME)
2802 {
2803 controlt *c = tunnel[t].controls;
2804 uint8_t w = tunnel[t].window;
2805 tunnel[t].try++; // another try
2806 if (tunnel[t].try > 5)
2807 tunnelkill(t, "Timeout on control message"); // game over
2808 else
2809 while (c && w--)
2810 {
2811 tunnelsend(c->buf, c->length, t);
2812 c = c->next;
2813 }
2814
2815 t_actions++;
2816 }
2817 }
2818 // Send hello
2819 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
2820 {
2821 controlt *c = controlnew(6); // sending HELLO
2822 controladd(c, 0, t); // send the message
2823 LOG(3, 0, t, "Sending HELLO message\n");
2824 t_actions++;
2825 }
2826
2827 // Check for tunnel changes requested from the CLI
2828 if ((a = cli_tunnel_actions[t].action))
2829 {
2830 cli_tunnel_actions[t].action = 0;
2831 if (a & CLI_TUN_KILL)
2832 {
2833 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2834 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2835 t_actions++;
2836 }
2837 }
2838 }
2839
2840 for (i = 0; i < r_slice; i++)
2841 {
2842 r++;
2843 if (r >= MAXRADIUS)
2844 r = 1;
2845
2846 if (!radius[r].state)
2847 continue;
2848
2849 if (radius[r].retry <= TIME)
2850 {
2851 radiusretry(r);
2852 r_actions++;
2853 }
2854 }
2855
2856 for (i = 0; i < s_slice; i++)
2857 {
2858 s++;
2859 if (s > config->cluster_highest_sessionid)
2860 s = 1;
2861
2862 if (!session[s].opened) // Session isn't in use
2863 continue;
2864
2865 // check for expired sessions
2866 if (session[s].die)
2867 {
2868 if (session[s].die <= TIME)
2869 {
2870 sessionkill(s, "Expired");
2871 s_actions++;
2872 }
2873 continue;
2874 }
2875
2876 // PPP timeouts
2877 if (sess_local[s].lcp.restart <= time_now)
2878 {
2879 int next_state = session[s].ppp.lcp;
2880 switch (session[s].ppp.lcp)
2881 {
2882 case RequestSent:
2883 case AckReceived:
2884 next_state = RequestSent;
2885
2886 case AckSent:
2887 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2888 {
2889 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2890 sendlcp(s, session[s].tunnel);
2891 change_state(s, lcp, next_state);
2892 }
2893 else
2894 {
2895 sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
2896 STAT(session_timeout);
2897 }
2898
2899 s_actions++;
2900 }
2901
2902 if (session[s].die)
2903 continue;
2904 }
2905
2906 if (sess_local[s].ipcp.restart <= time_now)
2907 {
2908 int next_state = session[s].ppp.ipcp;
2909 switch (session[s].ppp.ipcp)
2910 {
2911 case RequestSent:
2912 case AckReceived:
2913 next_state = RequestSent;
2914
2915 case AckSent:
2916 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2917 {
2918 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2919 sendipcp(s, session[s].tunnel);
2920 change_state(s, ipcp, next_state);
2921 }
2922 else
2923 {
2924 sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
2925 STAT(session_timeout);
2926 }
2927
2928 s_actions++;
2929 }
2930
2931 if (session[s].die)
2932 continue;
2933 }
2934
2935 if (sess_local[s].ipv6cp.restart <= time_now)
2936 {
2937 int next_state = session[s].ppp.ipv6cp;
2938 switch (session[s].ppp.ipv6cp)
2939 {
2940 case RequestSent:
2941 case AckReceived:
2942 next_state = RequestSent;
2943
2944 case AckSent:
2945 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2946 {
2947 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2948 sendipv6cp(s, session[s].tunnel);
2949 change_state(s, ipv6cp, next_state);
2950 }
2951 else
2952 {
2953 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2954 change_state(s, ipv6cp, Stopped);
2955 }
2956
2957 s_actions++;
2958 }
2959 }
2960
2961 if (sess_local[s].ccp.restart <= time_now)
2962 {
2963 int next_state = session[s].ppp.ccp;
2964 switch (session[s].ppp.ccp)
2965 {
2966 case RequestSent:
2967 case AckReceived:
2968 next_state = RequestSent;
2969
2970 case AckSent:
2971 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2972 {
2973 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2974 sendccp(s, session[s].tunnel);
2975 change_state(s, ccp, next_state);
2976 }
2977 else
2978 {
2979 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2980 change_state(s, ccp, Stopped);
2981 }
2982
2983 s_actions++;
2984 }
2985 }
2986
2987 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2988 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2989 {
2990 sessionshutdown(s, "No response to LCP ECHO requests.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
2991 STAT(session_timeout);
2992 s_actions++;
2993 continue;
2994 }
2995
2996 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2997 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
2998 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
2999 {
3000 uint8_t b[MAXETHER];
3001
3002 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
3003 if (!q) continue;
3004
3005 *q = EchoReq;
3006 *(uint8_t *)(q + 1) = (time_now % 255); // ID
3007 *(uint16_t *)(q + 2) = htons(8); // Length
3008 *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
3009
3010 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
3011 (int)(time_now - session[s].last_packet));
3012 tunnelsend(b, 24, session[s].tunnel); // send it
3013 sess_local[s].last_echo = time_now;
3014 s_actions++;
3015 }
3016
3017 // Check for actions requested from the CLI
3018 if ((a = cli_session_actions[s].action))
3019 {
3020 int send = 0;
3021
3022 cli_session_actions[s].action = 0;
3023 if (a & CLI_SESS_KILL)
3024 {
3025 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
3026 sessionshutdown(s, "Requested by administrator.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
3027 a = 0; // dead, no need to check for other actions
3028 s_actions++;
3029 }
3030
3031 if (a & CLI_SESS_NOSNOOP)
3032 {
3033 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
3034 session[s].snoop_ip = 0;
3035 session[s].snoop_port = 0;
3036 s_actions++;
3037 send++;
3038 }
3039 else if (a & CLI_SESS_SNOOP)
3040 {
3041 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
3042 fmtaddr(cli_session_actions[s].snoop_ip, 0),
3043 cli_session_actions[s].snoop_port);
3044
3045 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
3046 session[s].snoop_port = cli_session_actions[s].snoop_port;
3047 s_actions++;
3048 send++;
3049 }
3050
3051 if (a & CLI_SESS_NOTHROTTLE)
3052 {
3053 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
3054 throttle_session(s, 0, 0);
3055 s_actions++;
3056 send++;
3057 }
3058 else if (a & CLI_SESS_THROTTLE)
3059 {
3060 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
3061 cli_session_actions[s].throttle_in,
3062 cli_session_actions[s].throttle_out);
3063
3064 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
3065 s_actions++;
3066 send++;
3067 }
3068
3069 if (a & CLI_SESS_NOFILTER)
3070 {
3071 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3072 filter_session(s, 0, 0);
3073 s_actions++;
3074 send++;
3075 }
3076 else if (a & CLI_SESS_FILTER)
3077 {
3078 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3079 cli_session_actions[s].filter_in,
3080 cli_session_actions[s].filter_out);
3081
3082 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3083 s_actions++;
3084 send++;
3085 }
3086
3087 if (send)
3088 cluster_send_session(s);
3089 }
3090
3091 // RADIUS interim accounting
3092 if (config->radius_accounting && config->radius_interim > 0
3093 && session[s].ip && !session[s].walled_garden
3094 && !sess_local[s].radius // RADIUS already in progress
3095 && time_now - sess_local[s].last_interim >= config->radius_interim)
3096 {
3097 int rad = radiusnew(s);
3098 if (!rad)
3099 {
3100 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3101 STAT(radius_overflow);
3102 continue;
3103 }
3104
3105 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3106 session[s].user, session[s].unique_id);
3107
3108 radiussend(rad, RADIUSINTERIM);
3109 sess_local[s].last_interim = time_now;
3110 s_actions++;
3111 }
3112 }
3113
3114 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3115 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3116 }
3117
3118 //
3119 // Are we in the middle of a tunnel update, or radius
3120 // requests??
3121 //
3122 static int still_busy(void)
3123 {
3124 int i;
3125 static clockt last_talked = 0;
3126 static clockt start_busy_wait = 0;
3127
3128 if (!config->cluster_iam_master)
3129 {
3130 #ifdef BGP
3131 static time_t stopped_bgp = 0;
3132 if (bgp_configured)
3133 {
3134 if (!stopped_bgp)
3135 {
3136 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3137
3138 for (i = 0; i < BGP_NUM_PEERS; i++)
3139 if (bgp_peers[i].state == Established)
3140 bgp_stop(&bgp_peers[i]);
3141
3142 stopped_bgp = time_now;
3143
3144 // we don't want to become master
3145 cluster_send_ping(0);
3146
3147 return 1;
3148 }
3149
3150 if (time_now < (stopped_bgp + QUIT_DELAY))
3151 return 1;
3152 }
3153 #endif /* BGP */
3154
3155 return 0;
3156 }
3157
3158 if (main_quit == QUIT_SHUTDOWN)
3159 {
3160 static int dropped = 0;
3161 if (!dropped)
3162 {
3163 int i;
3164
3165 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3166 for (i = 1; i < MAXTUNNEL; i++)
3167 if (tunnel[i].ip || tunnel[i].state)
3168 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3169
3170 dropped = 1;
3171 }
3172 }
3173
3174 if (start_busy_wait == 0)
3175 start_busy_wait = TIME;
3176
3177 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3178 {
3179 if (!tunnel[i].controlc)
3180 continue;
3181
3182 if (last_talked != TIME)
3183 {
3184 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3185 last_talked = TIME;
3186 }
3187 return 1;
3188 }
3189
3190 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3191 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3192 {
3193 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3194 return 0;
3195 }
3196
3197 for (i = 1; i < MAXRADIUS; i++)
3198 {
3199 if (radius[i].state == RADIUSNULL)
3200 continue;
3201 if (radius[i].state == RADIUSWAIT)
3202 continue;
3203
3204 if (last_talked != TIME)
3205 {
3206 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3207 last_talked = TIME;
3208 }
3209 return 1;
3210 }
3211
3212 return 0;
3213 }
3214
3215 #ifdef HAVE_EPOLL
3216 # include <sys/epoll.h>
3217 #else
3218 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3219 # include "fake_epoll.h"
3220 #endif
3221
3222 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3223 #define BASE_FDS 6
3224
3225 // additional polled fds
3226 #ifdef BGP
3227 # define EXTRA_FDS BGP_NUM_PEERS
3228 #else
3229 # define EXTRA_FDS 0
3230 #endif
3231
3232 // main loop - gets packets on tun or udp and processes them
3233 static void mainloop(void)
3234 {
3235 int i;
3236 uint8_t buf[65536];
3237 clockt next_cluster_ping = 0; // send initial ping immediately
3238 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3239 int maxevent = sizeof(events)/sizeof(*events);
3240
3241 if ((epollfd = epoll_create(maxevent)) < 0)
3242 {
3243 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3244 exit(1);
3245 }
3246
3247 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3248 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3249
3250 /* setup our fds to poll for input */
3251 {
3252 static struct event_data d[BASE_FDS];
3253 struct epoll_event e;
3254
3255 e.events = EPOLLIN;
3256 i = 0;
3257
3258 d[i].type = FD_TYPE_CLI;
3259 e.data.ptr = &d[i++];
3260 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3261
3262 d[i].type = FD_TYPE_CLUSTER;
3263 e.data.ptr = &d[i++];
3264 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3265
3266 d[i].type = FD_TYPE_TUN;
3267 e.data.ptr = &d[i++];
3268 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3269
3270 d[i].type = FD_TYPE_UDP;
3271 e.data.ptr = &d[i++];
3272 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3273
3274 d[i].type = FD_TYPE_CONTROL;
3275 e.data.ptr = &d[i++];
3276 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3277
3278 d[i].type = FD_TYPE_DAE;
3279 e.data.ptr = &d[i++];
3280 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3281 }
3282
3283 #ifdef BGP
3284 signal(SIGPIPE, SIG_IGN);
3285 bgp_setup(config->as_number);
3286 if (config->bind_address)
3287 bgp_add_route(config->bind_address, 0xffffffff);
3288
3289 for (i = 0; i < BGP_NUM_PEERS; i++)
3290 {
3291 if (config->neighbour[i].name[0])
3292 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3293 config->neighbour[i].as, config->neighbour[i].keepalive,
3294 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3295 }
3296 #endif /* BGP */
3297
3298 while (!main_quit || still_busy())
3299 {
3300 int more = 0;
3301 int n;
3302
3303
3304 if (main_reload)
3305 {
3306 main_reload = 0;
3307 read_config_file();
3308 config->reload_config++;
3309 }
3310
3311 if (config->reload_config)
3312 {
3313 config->reload_config = 0;
3314 update_config();
3315 }
3316
3317 #ifdef BGP
3318 bgp_set_poll();
3319 #endif /* BGP */
3320
3321 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3322 STAT(select_called);
3323
3324 TIME = now(NULL);
3325 if (n < 0)
3326 {
3327 if (errno == EINTR ||
3328 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3329 continue;
3330
3331 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3332 break; // exit
3333 }
3334
3335 if (n)
3336 {
3337 struct sockaddr_in addr;
3338 struct in_addr local;
3339 socklen_t alen;
3340 int c, s;
3341 int udp_ready = 0;
3342 int tun_ready = 0;
3343 int cluster_ready = 0;
3344 int udp_pkts = 0;
3345 int tun_pkts = 0;
3346 int cluster_pkts = 0;
3347 #ifdef BGP
3348 uint32_t bgp_events[BGP_NUM_PEERS];
3349 memset(bgp_events, 0, sizeof(bgp_events));
3350 #endif /* BGP */
3351
3352 for (c = n, i = 0; i < c; i++)
3353 {
3354 struct event_data *d = events[i].data.ptr;
3355
3356 switch (d->type)
3357 {
3358 case FD_TYPE_CLI: // CLI connections
3359 {
3360 int cli;
3361
3362 alen = sizeof(addr);
3363 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3364 {
3365 cli_do(cli);
3366 close(cli);
3367 }
3368 else
3369 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3370
3371 n--;
3372 break;
3373 }
3374
3375 // these are handled below, with multiple interleaved reads
3376 case FD_TYPE_CLUSTER: cluster_ready++; break;
3377 case FD_TYPE_TUN: tun_ready++; break;
3378 case FD_TYPE_UDP: udp_ready++; break;
3379
3380 case FD_TYPE_CONTROL: // nsctl commands
3381 alen = sizeof(addr);
3382 s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3383 if (s > 0) processcontrol(buf, s, &addr, alen, &local);
3384 n--;
3385 break;
3386
3387 case FD_TYPE_DAE: // DAE requests
3388 alen = sizeof(addr);
3389 s = recvfromto(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3390 if (s > 0) processdae(buf, s, &addr, alen, &local);
3391 n--;
3392 break;
3393
3394 case FD_TYPE_RADIUS: // RADIUS response
3395 alen = sizeof(addr);
3396 s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
3397 if (s >= 0 && config->cluster_iam_master)
3398 {
3399 if (addr.sin_addr.s_addr == config->radiusserver[0] ||
3400 addr.sin_addr.s_addr == config->radiusserver[1])
3401 processrad(buf, s, d->index);
3402 else
3403 LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
3404 fmtaddr(addr.sin_addr.s_addr, 0));
3405 }
3406
3407 n--;
3408 break;
3409
3410 #ifdef BGP
3411 case FD_TYPE_BGP:
3412 bgp_events[d->index] = events[i].events;
3413 n--;
3414 break;
3415 #endif /* BGP */
3416
3417 default:
3418 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3419 }
3420 }
3421
3422 #ifdef BGP
3423 bgp_process(bgp_events);
3424 #endif /* BGP */
3425
3426 for (c = 0; n && c < config->multi_read_count; c++)
3427 {
3428 // L2TP
3429 if (udp_ready)
3430 {
3431 alen = sizeof(addr);
3432 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3433 {
3434 processudp(buf, s, &addr);
3435 udp_pkts++;
3436 }
3437 else
3438 {
3439 udp_ready = 0;
3440 n--;
3441 }
3442 }
3443
3444 // incoming IP
3445 if (tun_ready)
3446 {
3447 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3448 {
3449 processtun(buf, s);
3450 tun_pkts++;
3451 }
3452 else
3453 {
3454 tun_ready = 0;
3455 n--;
3456 }
3457 }
3458
3459 // cluster
3460 if (cluster_ready)
3461 {
3462 alen = sizeof(addr);
3463 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3464 {
3465 processcluster(buf, s, addr.sin_addr.s_addr);
3466 cluster_pkts++;
3467 }
3468 else
3469 {
3470 cluster_ready = 0;
3471 n--;
3472 }
3473 }
3474 }
3475
3476 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3477 STAT(multi_read_used);
3478
3479 if (c >= config->multi_read_count)
3480 {
3481 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3482 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3483
3484 STAT(multi_read_exceeded);
3485 more++;
3486 }
3487 }
3488
3489 if (time_changed)
3490 {
3491 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
3492
3493 // Log current traffic stats
3494 snprintf(config->bandwidth, sizeof(config->bandwidth),
3495 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3496 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
3497 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
3498 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
3499
3500 udp_tx = udp_rx = 0;
3501 udp_rx_pkt = eth_rx_pkt = 0;
3502 eth_tx = eth_rx = 0;
3503 time_changed = 0;
3504
3505 if (config->dump_speed)
3506 printf("%s\n", config->bandwidth);
3507
3508 // Update the internal time counter
3509 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3510
3511 {
3512 // Run timer hooks
3513 struct param_timer p = { time_now };
3514 run_plugins(PLUGIN_TIMER, &p);
3515 }
3516 }
3517
3518 // Runs on every machine (master and slaves).
3519 if (next_cluster_ping <= TIME)
3520 {
3521 // Check to see which of the cluster is still alive..
3522
3523 cluster_send_ping(basetime); // Only does anything if we're a slave
3524 cluster_check_master(); // ditto.
3525
3526 cluster_heartbeat(); // Only does anything if we're a master.
3527 cluster_check_slaves(); // ditto.
3528
3529 master_update_counts(); // If we're a slave, send our byte counters to our master.
3530
3531 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3532 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3533 else
3534 next_cluster_ping = TIME + config->cluster_hb_interval;
3535 }
3536
3537 if (!config->cluster_iam_master)
3538 continue;
3539
3540 // Run token bucket filtering queue..
3541 // Only run it every 1/10th of a second.
3542 {
3543 static clockt last_run = 0;
3544 if (last_run != TIME)
3545 {
3546 last_run = TIME;
3547 tbf_run_timer();
3548 }
3549 }
3550
3551 // Handle timeouts, retries etc.
3552 {
3553 static double last_clean = 0;
3554 double this_clean;
3555 double diff;
3556
3557 TIME = now(&this_clean);
3558 diff = this_clean - last_clean;
3559
3560 // Run during idle time (after we've handled
3561 // all incoming packets) or every 1/10th sec
3562 if (!more || diff > 0.1)
3563 {
3564 regular_cleanups(diff);
3565 last_clean = this_clean;
3566 }
3567 }
3568
3569 if (*config->accounting_dir)
3570 {
3571 static clockt next_acct = 0;
3572 static clockt next_shut_acct = 0;
3573
3574 if (next_acct <= TIME)
3575 {
3576 // Dump accounting data
3577 next_acct = TIME + ACCT_TIME;
3578 next_shut_acct = TIME + ACCT_SHUT_TIME;
3579 dump_acct_info(1);
3580 }
3581 else if (next_shut_acct <= TIME)
3582 {
3583 // Dump accounting data for shutdown sessions
3584 next_shut_acct = TIME + ACCT_SHUT_TIME;
3585 if (shut_acct_n)
3586 dump_acct_info(0);
3587 }
3588 }
3589 }
3590
3591 // Are we the master and shutting down??
3592 if (config->cluster_iam_master)
3593 cluster_heartbeat(); // Flush any queued changes..
3594
3595 // Ok. Notify everyone we're shutting down. If we're
3596 // the master, this will force an election.
3597 cluster_send_ping(0);
3598
3599 //
3600 // Important!!! We MUST not process any packets past this point!
3601 LOG(1, 0, 0, "Shutdown complete\n");
3602 }
3603
3604 static void stripdomain(char *host)
3605 {
3606 char *p;
3607
3608 if ((p = strchr(host, '.')))
3609 {
3610 char *domain = 0;
3611 char _domain[1024];
3612
3613 // strip off domain
3614 FILE *resolv = fopen("/etc/resolv.conf", "r");
3615 if (resolv)
3616 {
3617 char buf[1024];
3618 char *b;
3619
3620 while (fgets(buf, sizeof(buf), resolv))
3621 {
3622 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3623 continue;
3624
3625 if (!isspace(buf[6]))
3626 continue;
3627
3628 b = buf + 7;
3629 while (isspace(*b)) b++;
3630
3631 if (*b)
3632 {
3633 char *d = b;
3634 while (*b && !isspace(*b)) b++;
3635 *b = 0;
3636 if (buf[0] == 'd') // domain is canonical
3637 {
3638 domain = d;
3639 break;
3640 }
3641
3642 // first search line
3643 if (!domain)
3644 {
3645 // hold, may be subsequent domain line
3646 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3647 domain = _domain;
3648 }
3649 }
3650 }
3651
3652 fclose(resolv);
3653 }
3654
3655 if (domain)
3656 {
3657 int hl = strlen(host);
3658 int dl = strlen(domain);
3659 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3660 host[hl -dl - 1] = 0;
3661 }
3662 else
3663 {
3664 *p = 0; // everything after first dot
3665 }
3666 }
3667 }
3668
3669 // Init data structures
3670 static void initdata(int optdebug, char *optconfig)
3671 {
3672 int i;
3673
3674 if (!(config = shared_malloc(sizeof(configt))))
3675 {
3676 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3677 exit(1);
3678 }
3679
3680 memset(config, 0, sizeof(configt));
3681 time(&config->start_time);
3682 strncpy(config->config_file, optconfig, strlen(optconfig));
3683 config->debug = optdebug;
3684 config->num_tbfs = MAXTBFS;
3685 config->rl_rate = 28; // 28kbps
3686 config->cluster_mcast_ttl = 1;
3687 config->cluster_master_min_adv = 1;
3688 config->ppp_restart_time = 3;
3689 config->ppp_max_configure = 10;
3690 config->ppp_max_failure = 5;
3691 strcpy(config->random_device, RANDOMDEVICE);
3692
3693 log_stream = stderr;
3694
3695 #ifdef RINGBUFFER
3696 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3697 {
3698 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3699 exit(1);
3700 }
3701 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3702 #endif
3703
3704 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3705 {
3706 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3707 exit(1);
3708 }
3709 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3710 {
3711 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3712 exit(1);
3713 }
3714 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3715 {
3716 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3717 exit(1);
3718 }
3719
3720 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3721 {
3722 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3723 exit(1);
3724 }
3725
3726 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3727 {
3728 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3729 exit(1);
3730 }
3731
3732 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3733 {
3734 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3735 exit(1);
3736 }
3737
3738 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3739 {
3740 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3741 exit(1);
3742 }
3743 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3744
3745 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3746 {
3747 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3748 exit(1);
3749 }
3750 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3751
3752 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3753 {
3754 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3755 exit(1);
3756 }
3757 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3758
3759 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3760 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3761 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3762 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3763
3764 // Put all the sessions on the free list marked as undefined.
3765 for (i = 1; i < MAXSESSION; i++)
3766 {
3767 session[i].next = i + 1;
3768 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3769 }
3770 session[MAXSESSION - 1].next = 0;
3771 sessionfree = 1;
3772
3773 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3774 for (i = 1; i < MAXTUNNEL; i++)
3775 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3776
3777 if (!*hostname)
3778 {
3779 // Grab my hostname unless it's been specified
3780 gethostname(hostname, sizeof(hostname));
3781 stripdomain(hostname);
3782 }
3783
3784 _statistics->start_time = _statistics->last_reset = time(NULL);
3785
3786 #ifdef BGP
3787 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3788 {
3789 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3790 exit(1);
3791 }
3792 #endif /* BGP */
3793 }
3794
3795 static int assign_ip_address(sessionidt s)
3796 {
3797 uint32_t i;
3798 int best = -1;
3799 time_t best_time = time_now;
3800 char *u = session[s].user;
3801 char reuse = 0;
3802
3803
3804 CSTAT(assign_ip_address);
3805
3806 for (i = 1; i < ip_pool_size; i++)
3807 {
3808 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3809 continue;
3810
3811 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3812 {
3813 best = i;
3814 reuse = 1;
3815 break;
3816 }
3817
3818 if (ip_address_pool[i].last < best_time)
3819 {
3820 best = i;
3821 if (!(best_time = ip_address_pool[i].last))
3822 break; // never used, grab this one
3823 }
3824 }
3825
3826 if (best < 0)
3827 {
3828 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3829 return 0;
3830 }
3831
3832 session[s].ip = ip_address_pool[best].address;
3833 session[s].ip_pool_index = best;
3834 ip_address_pool[best].assigned = 1;
3835 ip_address_pool[best].last = time_now;
3836 ip_address_pool[best].session = s;
3837 if (session[s].walled_garden)
3838 /* Don't track addresses of users in walled garden (note: this
3839 means that their address isn't "sticky" even if they get
3840 un-gardened). */
3841 ip_address_pool[best].user[0] = 0;
3842 else
3843 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3844
3845 STAT(ip_allocated);
3846 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3847 reuse ? "Reusing" : "Allocating", best);
3848
3849 return 1;
3850 }
3851
3852 static void free_ip_address(sessionidt s)
3853 {
3854 int i = session[s].ip_pool_index;
3855
3856
3857 CSTAT(free_ip_address);
3858
3859 if (!session[s].ip)
3860 return; // what the?
3861
3862 if (i < 0) // Is this actually part of the ip pool?
3863 i = 0;
3864
3865 STAT(ip_freed);
3866 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3867 session[s].ip = 0;
3868 ip_address_pool[i].assigned = 0;
3869 ip_address_pool[i].session = 0;
3870 ip_address_pool[i].last = time_now;
3871 }
3872
3873 //
3874 // Fsck the address pool against the session table.
3875 // Normally only called when we become a master.
3876 //
3877 // This isn't perfect: We aren't keep tracking of which
3878 // users used to have an IP address.
3879 //
3880 void rebuild_address_pool(void)
3881 {
3882 int i;
3883
3884 //
3885 // Zero the IP pool allocation, and build
3886 // a map from IP address to pool index.
3887 for (i = 1; i < MAXIPPOOL; ++i)
3888 {
3889 ip_address_pool[i].assigned = 0;
3890 ip_address_pool[i].session = 0;
3891 if (!ip_address_pool[i].address)
3892 continue;
3893
3894 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3895 }
3896
3897 for (i = 0; i < MAXSESSION; ++i)
3898 {
3899 int ipid;
3900 if (!(session[i].opened && session[i].ip))
3901 continue;
3902
3903 ipid = - lookup_ipmap(htonl(session[i].ip));
3904
3905 if (session[i].ip_pool_index < 0)
3906 {
3907 // Not allocated out of the pool.
3908 if (ipid < 1) // Not found in the pool either? good.
3909 continue;
3910
3911 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3912 i, fmtaddr(session[i].ip, 0), ipid);
3913
3914 // Fall through and process it as part of the pool.
3915 }
3916
3917
3918 if (ipid > MAXIPPOOL || ipid < 0)
3919 {
3920 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3921 ipid = -1;
3922 session[i].ip_pool_index = ipid;
3923 continue;
3924 }
3925
3926 ip_address_pool[ipid].assigned = 1;
3927 ip_address_pool[ipid].session = i;
3928 ip_address_pool[ipid].last = time_now;
3929 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3930 session[i].ip_pool_index = ipid;
3931 cache_ipmap(session[i].ip, i); // Fix the ip map.
3932 }
3933 }
3934
3935 //
3936 // Fix the address pool to match a changed session.
3937 // (usually when the master sends us an update).
3938 static void fix_address_pool(int sid)
3939 {
3940 int ipid;
3941
3942 ipid = session[sid].ip_pool_index;
3943
3944 if (ipid > ip_pool_size)
3945 return; // Ignore it. rebuild_address_pool will fix it up.
3946
3947 if (ip_address_pool[ipid].address != session[sid].ip)
3948 return; // Just ignore it. rebuild_address_pool will take care of it.
3949
3950 ip_address_pool[ipid].assigned = 1;
3951 ip_address_pool[ipid].session = sid;
3952 ip_address_pool[ipid].last = time_now;
3953 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3954 }
3955
3956 //
3957 // Add a block of addresses to the IP pool to hand out.
3958 //
3959 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3960 {
3961 int i;
3962 if (mask == 0)
3963 mask = 0xffffffff; // Host route only.
3964
3965 addr &= mask;
3966
3967 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3968 return ;
3969
3970 for (i = addr ;(i & mask) == addr; ++i)
3971 {
3972 if ((i & 0xff) == 0 || (i&0xff) == 255)
3973 continue; // Skip 0 and broadcast addresses.
3974
3975 ip_address_pool[ip_pool_size].address = i;
3976 ip_address_pool[ip_pool_size].assigned = 0;
3977 ++ip_pool_size;
3978 if (ip_pool_size >= MAXIPPOOL)
3979 {
3980 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3981 return;
3982 }
3983 }
3984 }
3985
3986 // Initialize the IP address pool
3987 static void initippool()
3988 {
3989 FILE *f;
3990 char *p;
3991 char buf[4096];
3992 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3993
3994 if (!(f = fopen(IPPOOLFILE, "r")))
3995 {
3996 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3997 exit(1);
3998 }
3999
4000 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
4001 {
4002 char *pool = buf;
4003 buf[4095] = 0; // Force it to be zero terminated/
4004
4005 if (*buf == '#' || *buf == '\n')
4006 continue; // Skip comments / blank lines
4007 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
4008 if ((p = (char *)strchr(buf, ':')))
4009 {
4010 in_addr_t src;
4011 *p = '\0';
4012 src = inet_addr(buf);
4013 if (src == INADDR_NONE)
4014 {
4015 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
4016 exit(1);
4017 }
4018 // This entry is for a specific IP only
4019 if (src != config->bind_address)
4020 continue;
4021 *p = ':';
4022 pool = p+1;
4023 }
4024 if ((p = (char *)strchr(pool, '/')))
4025 {
4026 // It's a range
4027 int numbits = 0;
4028 in_addr_t start = 0, mask = 0;
4029
4030 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
4031 *p++ = 0;
4032 if (!*p || !(numbits = atoi(p)))
4033 {
4034 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
4035 continue;
4036 }
4037 start = ntohl(inet_addr(pool));
4038 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
4039
4040 // Add a static route for this pool
4041 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
4042 fmtaddr(htonl(start), 0), 32 + mask);
4043
4044 routeset(0, start, mask, 0, 1);
4045
4046 add_to_ip_pool(start, mask);
4047 }
4048 else
4049 {
4050 // It's a single ip address
4051 add_to_ip_pool(ntohl(inet_addr(pool)), 0);
4052 }
4053 }
4054 fclose(f);
4055 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
4056 }
4057
4058 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
4059 {
4060 struct sockaddr_in snoop_addr = {0};
4061 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
4062 return;
4063
4064 snoop_addr.sin_family = AF_INET;
4065 snoop_addr.sin_addr.s_addr = destination;
4066 snoop_addr.sin_port = ntohs(port);
4067
4068 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
4069 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
4070 htons(snoop_addr.sin_port));
4071
4072 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
4073 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
4074
4075 STAT(packets_snooped);
4076 }
4077
4078 static int dump_session(FILE **f, sessiont *s)
4079 {
4080 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
4081 return 1;
4082
4083 if (!*f)
4084 {
4085 char filename[1024];
4086 char timestr[64];
4087 time_t now = time(NULL);
4088
4089 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4090 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4091
4092 if (!(*f = fopen(filename, "w")))
4093 {
4094 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4095 return 0;
4096 }
4097
4098 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4099 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4100 "# host: %s\n"
4101 "# endpoint: %s\n"
4102 "# time: %ld\n"
4103 "# uptime: %ld\n"
4104 "# format: username ip qos uptxoctets downrxoctets\n",
4105 hostname,
4106 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
4107 now,
4108 now - basetime);
4109 }
4110
4111 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4112 fprintf(*f, "%s %s %d %u %u\n",
4113 s->user, // username
4114 fmtaddr(htonl(s->ip), 0), // ip
4115 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4116 (uint32_t) s->cin_delta, // uptxoctets
4117 (uint32_t) s->cout_delta); // downrxoctets
4118
4119 s->cin_delta = s->cout_delta = 0;
4120
4121 return 1;
4122 }
4123
4124 static void dump_acct_info(int all)
4125 {
4126 int i;
4127 FILE *f = NULL;
4128
4129
4130 CSTAT(dump_acct_info);
4131
4132 if (shut_acct_n)
4133 {
4134 for (i = 0; i < shut_acct_n; i++)
4135 dump_session(&f, &shut_acct[i]);
4136
4137 shut_acct_n = 0;
4138 }
4139
4140 if (all)
4141 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4142 dump_session(&f, &session[i]);
4143
4144 if (f)
4145 fclose(f);
4146 }
4147
4148 // Main program
4149 int main(int argc, char *argv[])
4150 {
4151 int i;
4152 int optdebug = 0;
4153 char *optconfig = CONFIGFILE;
4154
4155 time(&basetime); // start clock
4156
4157 // scan args
4158 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4159 {
4160 switch (i)
4161 {
4162 case 'd':
4163 if (fork()) exit(0);
4164 setsid();
4165 freopen("/dev/null", "r", stdin);
4166 freopen("/dev/null", "w", stdout);
4167 freopen("/dev/null", "w", stderr);
4168 break;
4169 case 'v':
4170 optdebug++;
4171 break;
4172 case 'c':
4173 optconfig = optarg;
4174 break;
4175 case 'h':
4176 snprintf(hostname, sizeof(hostname), "%s", optarg);
4177 break;
4178 default:
4179 printf("Args are:\n"
4180 "\t-d\t\tDetach from terminal\n"
4181 "\t-c <file>\tConfig file\n"
4182 "\t-h <hostname>\tForce hostname\n"
4183 "\t-v\t\tDebug\n");
4184
4185 return (0);
4186 break;
4187 }
4188 }
4189
4190 // Start the timer routine off
4191 time(&time_now);
4192 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4193
4194 initplugins();
4195 initdata(optdebug, optconfig);
4196
4197 init_cli(hostname);
4198 read_config_file();
4199 update_config();
4200 init_tbf(config->num_tbfs);
4201
4202 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4203 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4204 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4205 {
4206 struct rlimit rlim;
4207 rlim.rlim_cur = RLIM_INFINITY;
4208 rlim.rlim_max = RLIM_INFINITY;
4209 // Remove the maximum core size
4210 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4211 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4212
4213 // Make core dumps go to /tmp
4214 chdir("/tmp");
4215 }
4216
4217 if (config->scheduler_fifo)
4218 {
4219 int ret;
4220 struct sched_param params = {0};
4221 params.sched_priority = 1;
4222
4223 if (get_nprocs() < 2)
4224 {
4225 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4226 config->scheduler_fifo = 0;
4227 }
4228 else
4229 {
4230 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4231 {
4232 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4233 }
4234 else
4235 {
4236 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4237 config->scheduler_fifo = 0;
4238 }
4239 }
4240 }
4241
4242 /* Set up the cluster communications port. */
4243 if (cluster_init() < 0)
4244 exit(1);
4245
4246 inittun();
4247 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4248
4249 initudp();
4250 initrad();
4251 initippool();
4252
4253 // seed prng
4254 {
4255 unsigned seed = time_now ^ getpid();
4256 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4257 srand(seed);
4258 }
4259
4260 signal(SIGHUP, sighup_handler);
4261 signal(SIGCHLD, sigchild_handler);
4262 signal(SIGTERM, shutdown_handler);
4263 signal(SIGINT, shutdown_handler);
4264 signal(SIGQUIT, shutdown_handler);
4265
4266 // Prevent us from getting paged out
4267 if (config->lock_pages)
4268 {
4269 if (!mlockall(MCL_CURRENT))
4270 LOG(1, 0, 0, "Locking pages into memory\n");
4271 else
4272 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4273 }
4274
4275 // Drop privileges here
4276 if (config->target_uid > 0 && geteuid() == 0)
4277 setuid(config->target_uid);
4278
4279 mainloop();
4280
4281 /* remove plugins (so cleanup code gets run) */
4282 plugins_done();
4283
4284 // Remove the PID file if we wrote it
4285 if (config->wrote_pid && *config->pid_file == '/')
4286 unlink(config->pid_file);
4287
4288 /* kill CLI children */
4289 signal(SIGTERM, SIG_IGN);
4290 kill(0, SIGTERM);
4291 return 0;
4292 }
4293
4294 static void sighup_handler(int sig)
4295 {
4296 main_reload++;
4297 }
4298
4299 static void shutdown_handler(int sig)
4300 {
4301 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4302 }
4303
4304 static void sigchild_handler(int sig)
4305 {
4306 while (waitpid(-1, NULL, WNOHANG) > 0)
4307 ;
4308 }
4309
4310 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4311 {
4312 MD5_CTX ctx;
4313 *challenge_response = NULL;
4314
4315 if (!*config->l2tp_secret)
4316 {
4317 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4318 return;
4319 }
4320
4321 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4322
4323 *challenge_response = calloc(17, 1);
4324
4325 MD5_Init(&ctx);
4326 MD5_Update(&ctx, &id, 1);
4327 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4328 MD5_Update(&ctx, challenge, challenge_length);
4329 MD5_Final(*challenge_response, &ctx);
4330
4331 return;
4332 }
4333
4334 static int facility_value(char *name)
4335 {
4336 int i;
4337 for (i = 0; facilitynames[i].c_name; i++)
4338 {
4339 if (strcmp(facilitynames[i].c_name, name) == 0)
4340 return facilitynames[i].c_val;
4341 }
4342 return 0;
4343 }
4344
4345 static void update_config()
4346 {
4347 int i;
4348 char *p;
4349 static int timeout = 0;
4350 static int interval = 0;
4351
4352 // Update logging
4353 closelog();
4354 syslog_log = 0;
4355 if (log_stream)
4356 {
4357 if (log_stream != stderr)
4358 fclose(log_stream);
4359
4360 log_stream = NULL;
4361 }
4362
4363 if (*config->log_filename)
4364 {
4365 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4366 {
4367 char *p = config->log_filename + 7;
4368 if (*p)
4369 {
4370 openlog("l2tpns", LOG_PID, facility_value(p));
4371 syslog_log = 1;
4372 }
4373 }
4374 else if (strchr(config->log_filename, '/') == config->log_filename)
4375 {
4376 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4377 {
4378 fseek(log_stream, 0, SEEK_END);
4379 setbuf(log_stream, NULL);
4380 }
4381 else
4382 {
4383 log_stream = stderr;
4384 setbuf(log_stream, NULL);
4385 }
4386 }
4387 }
4388 else
4389 {
4390 log_stream = stderr;
4391 setbuf(log_stream, NULL);
4392 }
4393
4394 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4395 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4396
4397 if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
4398 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4399 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4400
4401 // reset MRU/MSS globals
4402 MRU = config->l2tp_mtu - L2TP_HDRS;
4403 if (MRU > PPPoE_MRU)
4404 MRU = PPPoE_MRU;
4405
4406 MSS = MRU - TCP_HDRS;
4407
4408 // Update radius
4409 config->numradiusservers = 0;
4410 for (i = 0; i < MAXRADSERVER; i++)
4411 if (config->radiusserver[i])
4412 {
4413 config->numradiusservers++;
4414 // Set radius port: if not set, take the port from the
4415 // first radius server. For the first radius server,
4416 // take the #defined default value from l2tpns.h
4417
4418 // test twice, In case someone works with
4419 // a secondary radius server without defining
4420 // a primary one, this will work even then.
4421 if (i > 0 && !config->radiusport[i])
4422 config->radiusport[i] = config->radiusport[i-1];
4423 if (!config->radiusport[i])
4424 config->radiusport[i] = RADPORT;
4425 }
4426
4427 if (!config->numradiusservers)
4428 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4429
4430 // parse radius_authtypes_s
4431 config->radius_authtypes = config->radius_authprefer = 0;
4432 p = config->radius_authtypes_s;
4433 while (p && *p)
4434 {
4435 char *s = strpbrk(p, " \t,");
4436 int type = 0;
4437
4438 if (s)
4439 {
4440 *s++ = 0;
4441 while (*s == ' ' || *s == '\t')
4442 s++;
4443
4444 if (!*s)
4445 s = 0;
4446 }
4447
4448 if (!strncasecmp("chap", p, strlen(p)))
4449 type = AUTHCHAP;
4450 else if (!strncasecmp("pap", p, strlen(p)))
4451 type = AUTHPAP;
4452 else
4453 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4454
4455 config->radius_authtypes |= type;
4456 if (!config->radius_authprefer)
4457 config->radius_authprefer = type;
4458
4459 p = s;
4460 }
4461
4462 if (!config->radius_authtypes)
4463 {
4464 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4465 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4466 }
4467
4468 // normalise radius_authtypes_s
4469 if (config->radius_authprefer == AUTHPAP)
4470 {
4471 strcpy(config->radius_authtypes_s, "pap");
4472 if (config->radius_authtypes & AUTHCHAP)
4473 strcat(config->radius_authtypes_s, ", chap");
4474 }
4475 else
4476 {
4477 strcpy(config->radius_authtypes_s, "chap");
4478 if (config->radius_authtypes & AUTHPAP)
4479 strcat(config->radius_authtypes_s, ", pap");
4480 }
4481
4482 if (!config->radius_dae_port)
4483 config->radius_dae_port = DAEPORT;
4484
4485 // re-initialise the random number source
4486 initrandom(config->random_device);
4487
4488 // Update plugins
4489 for (i = 0; i < MAXPLUGINS; i++)
4490 {
4491 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4492 continue;
4493
4494 if (*config->plugins[i])
4495 {
4496 // Plugin added
4497 add_plugin(config->plugins[i]);
4498 }
4499 else if (*config->old_plugins[i])
4500 {
4501 // Plugin removed
4502 remove_plugin(config->old_plugins[i]);
4503 }
4504 }
4505
4506 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4507 if (!config->multi_read_count) config->multi_read_count = 10;
4508 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4509 if (!*config->cluster_interface)
4510 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4511
4512 if (!config->cluster_hb_interval)
4513 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4514
4515 if (!config->cluster_hb_timeout)
4516 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4517
4518 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4519 {
4520 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4521 // late, ensure we're sufficiently larger than that
4522 int t = 4 * config->cluster_hb_interval + 11;
4523
4524 if (config->cluster_hb_timeout < t)
4525 {
4526 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4527 config->cluster_hb_timeout = t;
4528 }
4529
4530 // Push timing changes to the slaves immediately if we're the master
4531 if (config->cluster_iam_master)
4532 cluster_heartbeat();
4533
4534 interval = config->cluster_hb_interval;
4535 timeout = config->cluster_hb_timeout;
4536 }
4537
4538 // Write PID file
4539 if (*config->pid_file == '/' && !config->wrote_pid)
4540 {
4541 FILE *f;
4542 if ((f = fopen(config->pid_file, "w")))
4543 {
4544 fprintf(f, "%d\n", getpid());
4545 fclose(f);
4546 config->wrote_pid = 1;
4547 }
4548 else
4549 {
4550 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4551 }
4552 }
4553 }
4554
4555 static void read_config_file()
4556 {
4557 FILE *f;
4558
4559 if (!config->config_file) return;
4560 if (!(f = fopen(config->config_file, "r")))
4561 {
4562 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4563 return;
4564 }
4565
4566 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4567 cli_do_file(f);
4568 LOG(3, 0, 0, "Done reading config file\n");
4569 fclose(f);
4570 }
4571
4572 int sessionsetup(sessionidt s, tunnelidt t)
4573 {
4574 // A session now exists, set it up
4575 in_addr_t ip;
4576 char *user;
4577 sessionidt i;
4578 int r;
4579
4580 CSTAT(sessionsetup);
4581
4582 LOG(3, s, t, "Doing session setup for session\n");
4583
4584 if (!session[s].ip)
4585 {
4586 assign_ip_address(s);
4587 if (!session[s].ip)
4588 {
4589 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4590 sessionshutdown(s, "No IP addresses available.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
4591 return 0;
4592 }
4593 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4594 fmtaddr(htonl(session[s].ip), 0));
4595 }
4596
4597
4598 // Make sure this is right
4599 session[s].tunnel = t;
4600
4601 // zap old sessions with same IP and/or username
4602 // Don't kill gardened sessions - doing so leads to a DoS
4603 // from someone who doesn't need to know the password
4604 {
4605 ip = session[s].ip;
4606 user = session[s].user;
4607 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4608 {
4609 if (i == s) continue;
4610 if (!session[s].opened) continue;
4611 if (ip == session[i].ip)
4612 {
4613 sessionkill(i, "Duplicate IP address");
4614 continue;
4615 }
4616
4617 if (config->allow_duplicate_users) continue;
4618 if (session[s].walled_garden || session[i].walled_garden) continue;
4619 if (!strcasecmp(user, session[i].user))
4620 sessionkill(i, "Duplicate session for users");
4621 }
4622 }
4623
4624 {
4625 int routed = 0;
4626
4627 // Add the route for this session.
4628 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4629 {
4630 if ((session[s].ip & session[s].route[r].mask) ==
4631 (session[s].route[r].ip & session[s].route[r].mask))
4632 routed++;
4633
4634 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4635 }
4636
4637 // Static IPs need to be routed if not already
4638 // convered by a Framed-Route. Anything else is part
4639 // of the IP address pool and is already routed, it
4640 // just needs to be added to the IP cache.
4641 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4642 if (session[s].ip_pool_index == -1) // static ip
4643 {
4644 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4645 }
4646 else
4647 cache_ipmap(session[s].ip, s);
4648 }
4649
4650 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4651 lcp_open(s, t); // transition to Network phase and send initial IPCP
4652
4653 // Run the plugin's against this new session.
4654 {
4655 struct param_new_session data = { &tunnel[t], &session[s] };
4656 run_plugins(PLUGIN_NEW_SESSION, &data);
4657 }
4658
4659 // Allocate TBFs if throttled
4660 if (session[s].throttle_in || session[s].throttle_out)
4661 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4662
4663 session[s].last_packet = time_now;
4664
4665 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4666 fmtaddr(htonl(session[s].ip), 0),
4667 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4668
4669 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4670
4671 return 1; // RADIUS OK and IP allocated, done...
4672 }
4673
4674 //
4675 // This session just got dropped on us by the master or something.
4676 // Make sure our tables up up to date...
4677 //
4678 int load_session(sessionidt s, sessiont *new)
4679 {
4680 int i;
4681 int newip = 0;
4682
4683 // Sanity checks.
4684 if (new->ip_pool_index >= MAXIPPOOL ||
4685 new->tunnel >= MAXTUNNEL)
4686 {
4687 LOG(0, s, 0, "Strange session update received!\n");
4688 // FIXME! What to do here?
4689 return 0;
4690 }
4691
4692 //
4693 // Ok. All sanity checks passed. Now we're committed to
4694 // loading the new session.
4695 //
4696
4697 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4698
4699 // See if routes/ip cache need updating
4700 if (new->ip != session[s].ip)
4701 newip++;
4702
4703 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4704 if (new->route[i].ip != session[s].route[i].ip ||
4705 new->route[i].mask != session[s].route[i].mask)
4706 newip++;
4707
4708 // needs update
4709 if (newip)
4710 {
4711 int routed = 0;
4712
4713 // remove old routes...
4714 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4715 {
4716 if ((session[s].ip & session[s].route[i].mask) ==
4717 (session[s].route[i].ip & session[s].route[i].mask))
4718 routed++;
4719
4720 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4721 }
4722
4723 // ...ip
4724 if (session[s].ip)
4725 {
4726 if (session[s].ip_pool_index == -1) // static IP
4727 {
4728 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4729 }
4730 else // It's part of the IP pool, remove it manually.
4731 uncache_ipmap(session[s].ip);
4732 }
4733
4734 routed = 0;
4735
4736 // add new routes...
4737 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4738 {
4739 if ((new->ip & new->route[i].mask) ==
4740 (new->route[i].ip & new->route[i].mask))
4741 routed++;
4742
4743 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4744 }
4745
4746 // ...ip
4747 if (new->ip)
4748 {
4749 // If there's a new one, add it.
4750 if (new->ip_pool_index == -1)
4751 {
4752 if (!routed) routeset(s, new->ip, 0, 0, 1);
4753 }
4754 else
4755 cache_ipmap(new->ip, s);
4756 }
4757 }
4758
4759 // check v6 routing
4760 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4761 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4762
4763 // check filters
4764 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4765 {
4766 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4767 new->filter_in = 0;
4768 }
4769
4770 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4771 {
4772 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4773 new->filter_out = 0;
4774 }
4775
4776 if (new->filter_in != session[s].filter_in)
4777 {
4778 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4779 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4780 }
4781
4782 if (new->filter_out != session[s].filter_out)
4783 {
4784 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4785 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4786 }
4787
4788 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4789 // for walking the sessions to forward byte counts to the master.
4790 config->cluster_highest_sessionid = s;
4791
4792 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4793
4794 // Do fixups into address pool.
4795 if (new->ip_pool_index != -1)
4796 fix_address_pool(s);
4797
4798 return 1;
4799 }
4800
4801 static void initplugins()
4802 {
4803 int i;
4804
4805 loaded_plugins = ll_init();
4806 // Initialize the plugins to nothing
4807 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4808 plugins[i] = ll_init();
4809 }
4810
4811 static void *open_plugin(char *plugin_name, int load)
4812 {
4813 char path[256] = "";
4814
4815 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4816 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4817 return dlopen(path, RTLD_NOW);
4818 }
4819
4820 // plugin callback to get a config value
4821 static void *getconfig(char *key, enum config_typet type)
4822 {
4823 int i;
4824
4825 for (i = 0; config_values[i].key; i++)
4826 {
4827 if (!strcmp(config_values[i].key, key))
4828 {
4829 if (config_values[i].type == type)
4830 return ((void *) config) + config_values[i].offset;
4831
4832 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4833 key, type, config_values[i].type);
4834
4835 return 0;
4836 }
4837 }
4838
4839 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4840 return 0;
4841 }
4842
4843 static int add_plugin(char *plugin_name)
4844 {
4845 static struct pluginfuncs funcs = {
4846 _log,
4847 _log_hex,
4848 fmtaddr,
4849 sessionbyuser,
4850 sessiontbysessionidt,
4851 sessionidtbysessiont,
4852 radiusnew,
4853 radiussend,
4854 getconfig,
4855 sessionshutdown,
4856 sessionkill,
4857 throttle_session,
4858 cluster_send_session,
4859 };
4860
4861 void *p = open_plugin(plugin_name, 1);
4862 int (*initfunc)(struct pluginfuncs *);
4863 int i;
4864
4865 if (!p)
4866 {
4867 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4868 return -1;
4869 }
4870
4871 if (ll_contains(loaded_plugins, p))
4872 {
4873 dlclose(p);
4874 return 0; // already loaded
4875 }
4876
4877 {
4878 int *v = dlsym(p, "plugin_api_version");
4879 if (!v || *v != PLUGIN_API_VERSION)
4880 {
4881 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4882 dlclose(p);
4883 return -1;
4884 }
4885 }
4886
4887 if ((initfunc = dlsym(p, "plugin_init")))
4888 {
4889 if (!initfunc(&funcs))
4890 {
4891 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4892 dlclose(p);
4893 return -1;
4894 }
4895 }
4896
4897 ll_push(loaded_plugins, p);
4898
4899 for (i = 0; i < max_plugin_functions; i++)
4900 {
4901 void *x;
4902 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4903 {
4904 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4905 ll_push(plugins[i], x);
4906 }
4907 }
4908
4909 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4910 return 1;
4911 }
4912
4913 static void run_plugin_done(void *plugin)
4914 {
4915 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4916
4917 if (donefunc)
4918 donefunc();
4919 }
4920
4921 static int remove_plugin(char *plugin_name)
4922 {
4923 void *p = open_plugin(plugin_name, 0);
4924 int loaded = 0;
4925
4926 if (!p)
4927 return -1;
4928
4929 if (ll_contains(loaded_plugins, p))
4930 {
4931 int i;
4932 for (i = 0; i < max_plugin_functions; i++)
4933 {
4934 void *x;
4935 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4936 ll_delete(plugins[i], x);
4937 }
4938
4939 ll_delete(loaded_plugins, p);
4940 run_plugin_done(p);
4941 loaded = 1;
4942 }
4943
4944 dlclose(p);
4945 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4946 return loaded;
4947 }
4948
4949 int run_plugins(int plugin_type, void *data)
4950 {
4951 int (*func)(void *data);
4952
4953 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4954 return PLUGIN_RET_ERROR;
4955
4956 ll_reset(plugins[plugin_type]);
4957 while ((func = ll_next(plugins[plugin_type])))
4958 {
4959 int r = func(data);
4960
4961 if (r != PLUGIN_RET_OK)
4962 return r; // stop here
4963 }
4964
4965 return PLUGIN_RET_OK;
4966 }
4967
4968 static void plugins_done()
4969 {
4970 void *p;
4971
4972 ll_reset(loaded_plugins);
4973 while ((p = ll_next(loaded_plugins)))
4974 run_plugin_done(p);
4975 }
4976
4977 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
4978 {
4979 struct nsctl request;
4980 struct nsctl response;
4981 int type = unpack_control(&request, buf, len);
4982 int r;
4983 void *p;
4984
4985 if (log_stream && config->debug >= 4)
4986 {
4987 if (type < 0)
4988 {
4989 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4990 fmtaddr(addr->sin_addr.s_addr, 0), type);
4991 }
4992 else
4993 {
4994 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4995 dump_control(&request, log_stream);
4996 }
4997 }
4998
4999 switch (type)
5000 {
5001 case NSCTL_REQ_LOAD:
5002 if (request.argc != 1)
5003 {
5004 response.type = NSCTL_RES_ERR;
5005 response.argc = 1;
5006 response.argv[0] = "name of plugin required";
5007 }
5008 else if ((r = add_plugin(request.argv[0])) < 1)
5009 {
5010 response.type = NSCTL_RES_ERR;
5011 response.argc = 1;
5012 response.argv[0] = !r
5013 ? "plugin already loaded"
5014 : "error loading plugin";
5015 }
5016 else
5017 {
5018 response.type = NSCTL_RES_OK;
5019 response.argc = 0;
5020 }
5021
5022 break;
5023
5024 case NSCTL_REQ_UNLOAD:
5025 if (request.argc != 1)
5026 {
5027 response.type = NSCTL_RES_ERR;
5028 response.argc = 1;
5029 response.argv[0] = "name of plugin required";
5030 }
5031 else if ((r = remove_plugin(request.argv[0])) < 1)
5032 {
5033 response.type = NSCTL_RES_ERR;
5034 response.argc = 1;
5035 response.argv[0] = !r
5036 ? "plugin not loaded"
5037 : "plugin not found";
5038 }
5039 else
5040 {
5041 response.type = NSCTL_RES_OK;
5042 response.argc = 0;
5043 }
5044
5045 break;
5046
5047 case NSCTL_REQ_HELP:
5048 response.type = NSCTL_RES_OK;
5049 response.argc = 0;
5050
5051 ll_reset(loaded_plugins);
5052 while ((p = ll_next(loaded_plugins)))
5053 {
5054 char **help = dlsym(p, "plugin_control_help");
5055 while (response.argc < 0xff && help && *help)
5056 response.argv[response.argc++] = *help++;
5057 }
5058
5059 break;
5060
5061 case NSCTL_REQ_CONTROL:
5062 {
5063 struct param_control param = {
5064 config->cluster_iam_master,
5065 request.argc,
5066 request.argv,
5067 0,
5068 NULL,
5069 };
5070
5071 int r = run_plugins(PLUGIN_CONTROL, &param);
5072
5073 if (r == PLUGIN_RET_ERROR)
5074 {
5075 response.type = NSCTL_RES_ERR;
5076 response.argc = 1;
5077 response.argv[0] = param.additional
5078 ? param.additional
5079 : "error returned by plugin";
5080 }
5081 else if (r == PLUGIN_RET_NOTMASTER)
5082 {
5083 static char msg[] = "must be run on master: 000.000.000.000";
5084
5085 response.type = NSCTL_RES_ERR;
5086 response.argc = 1;
5087 if (config->cluster_master_address)
5088 {
5089 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5090 response.argv[0] = msg;
5091 }
5092 else
5093 {
5094 response.argv[0] = "must be run on master: none elected";
5095 }
5096 }
5097 else if (!(param.response & NSCTL_RESPONSE))
5098 {
5099 response.type = NSCTL_RES_ERR;
5100 response.argc = 1;
5101 response.argv[0] = param.response
5102 ? "unrecognised response value from plugin"
5103 : "unhandled action";
5104 }
5105 else
5106 {
5107 response.type = param.response;
5108 response.argc = 0;
5109 if (param.additional)
5110 {
5111 response.argc = 1;
5112 response.argv[0] = param.additional;
5113 }
5114 }
5115 }
5116
5117 break;
5118
5119 default:
5120 response.type = NSCTL_RES_ERR;
5121 response.argc = 1;
5122 response.argv[0] = "error unpacking control packet";
5123 }
5124
5125 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5126 if (!buf)
5127 {
5128 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5129 return;
5130 }
5131
5132 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5133 if (r > 0)
5134 {
5135 sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
5136 if (log_stream && config->debug >= 4)
5137 {
5138 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5139 dump_control(&response, log_stream);
5140 }
5141 }
5142 else
5143 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5144 fmtaddr(addr->sin_addr.s_addr, 0), r);
5145
5146 free(buf);
5147 }
5148
5149 static tunnelidt new_tunnel()
5150 {
5151 tunnelidt i;
5152 for (i = 1; i < MAXTUNNEL; i++)
5153 {
5154 if (tunnel[i].state == TUNNELFREE)
5155 {
5156 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
5157 if (i > config->cluster_highest_tunnelid)
5158 config->cluster_highest_tunnelid = i;
5159 return i;
5160 }
5161 }
5162 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5163 return 0;
5164 }
5165
5166 //
5167 // We're becoming the master. Do any required setup..
5168 //
5169 // This is principally telling all the plugins that we're
5170 // now a master, and telling them about all the sessions
5171 // that are active too..
5172 //
5173 void become_master(void)
5174 {
5175 int s, i;
5176 static struct event_data d[RADIUS_FDS];
5177 struct epoll_event e;
5178
5179 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5180
5181 // running a bunch of iptables commands is slow and can cause
5182 // the master to drop tunnels on takeover--kludge around the
5183 // problem by forking for the moment (note: race)
5184 if (!fork_and_close())
5185 {
5186 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5187 {
5188 if (!session[s].opened) // Not an in-use session.
5189 continue;
5190
5191 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5192 }
5193 exit(0);
5194 }
5195
5196 // add radius fds
5197 e.events = EPOLLIN;
5198 for (i = 0; i < RADIUS_FDS; i++)
5199 {
5200 d[i].type = FD_TYPE_RADIUS;
5201 d[i].index = i;
5202 e.data.ptr = &d[i];
5203
5204 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5205 }
5206 }
5207
5208 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5209 {
5210 int s, i;
5211 int count = 0;
5212 int buckets[64];
5213
5214 if (CLI_HELP_REQUESTED)
5215 return CLI_HELP_NO_ARGS;
5216
5217 time(&time_now);
5218 for (i = 0; i < 64;++i) buckets[i] = 0;
5219
5220 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5221 {
5222 int idle;
5223 if (!session[s].opened)
5224 continue;
5225
5226 idle = time_now - session[s].last_packet;
5227 idle /= 5 ; // In multiples of 5 seconds.
5228 if (idle < 0)
5229 idle = 0;
5230 if (idle > 63)
5231 idle = 63;
5232
5233 ++count;
5234 ++buckets[idle];
5235 }
5236
5237 for (i = 0; i < 63; ++i)
5238 {
5239 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5240 }
5241 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5242 cli_print(cli, "%d total sessions open.", count);
5243 return CLI_OK;
5244 }
5245
5246 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5247 {
5248 int s, i;
5249 int count = 0;
5250 int buckets[64];
5251
5252 if (CLI_HELP_REQUESTED)
5253 return CLI_HELP_NO_ARGS;
5254
5255 time(&time_now);
5256 for (i = 0; i < 64;++i) buckets[i] = 0;
5257
5258 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5259 {
5260 int open = 0, d;
5261 if (!session[s].opened)
5262 continue;
5263
5264 d = time_now - session[s].opened;
5265 if (d < 0)
5266 d = 0;
5267 while (d > 1 && open < 32)
5268 {
5269 ++open;
5270 d >>= 1; // half.
5271 }
5272 ++count;
5273 ++buckets[open];
5274 }
5275
5276 s = 1;
5277 for (i = 0; i < 30; ++i)
5278 {
5279 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5280 s <<= 1;
5281 }
5282 cli_print(cli, "%d total sessions open.", count);
5283 return CLI_OK;
5284 }
5285
5286 /* Unhide an avp.
5287 *
5288 * This unencodes the AVP using the L2TP secret and the previously
5289 * stored random vector. It overwrites the hidden data with the
5290 * unhidden AVP subformat.
5291 */
5292 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5293 {
5294 MD5_CTX ctx;
5295 uint8_t digest[16];
5296 uint8_t *last;
5297 size_t d = 0;
5298 uint16_t m = htons(type);
5299
5300 // Compute initial pad
5301 MD5_Init(&ctx);
5302 MD5_Update(&ctx, (unsigned char *) &m, 2);
5303 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5304 MD5_Update(&ctx, vector, vec_len);
5305 MD5_Final(digest, &ctx);
5306
5307 // pointer to last decoded 16 octets
5308 last = value;
5309
5310 while (len > 0)
5311 {
5312 // calculate a new pad based on the last decoded block
5313 if (d >= sizeof(digest))
5314 {
5315 MD5_Init(&ctx);
5316 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5317 MD5_Update(&ctx, last, sizeof(digest));
5318 MD5_Final(digest, &ctx);
5319
5320 d = 0;
5321 last = value;
5322 }
5323
5324 *value++ ^= digest[d++];
5325 len--;
5326 }
5327 }
5328
5329 int find_filter(char const *name, size_t len)
5330 {
5331 int free = -1;
5332 int i;
5333
5334 for (i = 0; i < MAXFILTER; i++)
5335 {
5336 if (!*ip_filters[i].name)
5337 {
5338 if (free < 0)
5339 free = i;
5340
5341 continue;
5342 }
5343
5344 if (strlen(ip_filters[i].name) != len)
5345 continue;
5346
5347 if (!strncmp(ip_filters[i].name, name, len))
5348 return i;
5349 }
5350
5351 return free;
5352 }
5353
5354 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5355 {
5356 switch (p->op)
5357 {
5358 case FILTER_PORT_OP_EQ: return port == p->port;
5359 case FILTER_PORT_OP_NEQ: return port != p->port;
5360 case FILTER_PORT_OP_GT: return port > p->port;
5361 case FILTER_PORT_OP_LT: return port < p->port;
5362 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5363 }
5364
5365 return 0;
5366 }
5367
5368 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5369 {
5370 switch (op)
5371 {
5372 case FILTER_FLAG_OP_ANY:
5373 return (flags & sflags) || (~flags & cflags);
5374
5375 case FILTER_FLAG_OP_ALL:
5376 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5377
5378 case FILTER_FLAG_OP_EST:
5379 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5380 }
5381
5382 return 0;
5383 }
5384
5385 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5386 {
5387 uint16_t frag_offset;
5388 uint8_t proto;
5389 in_addr_t src_ip;
5390 in_addr_t dst_ip;
5391 uint16_t src_port = 0;
5392 uint16_t dst_port = 0;
5393 uint8_t flags = 0;
5394 ip_filter_rulet *rule;
5395
5396 if (len < 20) // up to end of destination address
5397 return 0;
5398
5399 if ((*buf >> 4) != 4) // IPv4
5400 return 0;
5401
5402 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5403 proto = buf[9];
5404 src_ip = *(in_addr_t *) (buf + 12);
5405 dst_ip = *(in_addr_t *) (buf + 16);
5406
5407 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5408 {
5409 int l = (buf[0] & 0xf) * 4; // length of IP header
5410 if (len < l + 4) // ports
5411 return 0;
5412
5413 src_port = ntohs(*(uint16_t *) (buf + l));
5414 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5415 if (proto == IPPROTO_TCP)
5416 {
5417 if (len < l + 14) // flags
5418 return 0;
5419
5420 flags = buf[l + 13] & 0x3f;
5421 }
5422 }
5423
5424 for (rule = ip_filters[filter].rules; rule->action; rule++)
5425 {
5426 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5427 continue;
5428
5429 if (rule->src_wild != INADDR_BROADCAST &&
5430 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5431 continue;
5432
5433 if (rule->dst_wild != INADDR_BROADCAST &&
5434 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5435 continue;
5436
5437 if (frag_offset)
5438 {
5439 // layer 4 deny rules are skipped
5440 if (rule->action == FILTER_ACTION_DENY &&
5441 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
5442 continue;
5443 }
5444 else
5445 {
5446 if (rule->frag)
5447 continue;
5448
5449 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5450 {
5451 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5452 continue;
5453
5454 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5455 continue;
5456
5457 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5458 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5459 continue;
5460 }
5461 }
5462
5463 // matched
5464 rule->counter++;
5465 return rule->action == FILTER_ACTION_PERMIT;
5466 }
5467
5468 // default deny
5469 return 0;
5470 }