93fcc29af7e83eae0bbe6a5c3d46fdbdd4b07d88
[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 1.121 2005-08-11 05:50:24 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 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
79 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
80
81 static void *ip_hash[256]; // Mapping from IP address to session structures.
82 struct ipv6radix {
83 int sess;
84 struct ipv6radix *branch;
85 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
86
87 // Traffic counters.
88 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
89 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
90 uint32_t eth_tx = 0;
91
92 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
93 time_t time_now = 0; // Current time in seconds since epoch.
94 static char time_now_string[64] = {0}; // Current time as a string.
95 char main_quit = 0; // True if we're in the process of exiting.
96 linked_list *loaded_plugins;
97 linked_list *plugins[MAX_PLUGIN_TYPES];
98
99 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
100 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
101
102 config_descriptt config_values[] = {
103 CONFIG("debug", debug, INT),
104 CONFIG("log_file", log_filename, STRING),
105 CONFIG("pid_file", pid_file, STRING),
106 CONFIG("random_device", random_device, STRING),
107 CONFIG("l2tp_secret", l2tpsecret, STRING),
108 CONFIG("ppp_restart_time", ppp_restart_time, INT),
109 CONFIG("ppp_max_configure", ppp_max_configure, INT),
110 CONFIG("ppp_max_failure", ppp_max_failure, INT),
111 CONFIG("primary_dns", default_dns1, IPv4),
112 CONFIG("secondary_dns", default_dns2, IPv4),
113 CONFIG("primary_radius", radiusserver[0], IPv4),
114 CONFIG("secondary_radius", radiusserver[1], IPv4),
115 CONFIG("primary_radius_port", radiusport[0], SHORT),
116 CONFIG("secondary_radius_port", radiusport[1], SHORT),
117 CONFIG("radius_accounting", radius_accounting, BOOL),
118 CONFIG("radius_interim", radius_interim, INT),
119 CONFIG("radius_secret", radiussecret, STRING),
120 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
121 CONFIG("radius_dae_port", radius_dae_port, SHORT),
122 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
123 CONFIG("bind_address", bind_address, IPv4),
124 CONFIG("peer_address", peer_address, IPv4),
125 CONFIG("send_garp", send_garp, BOOL),
126 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
127 CONFIG("throttle_buckets", num_tbfs, INT),
128 CONFIG("accounting_dir", accounting_dir, STRING),
129 CONFIG("setuid", target_uid, INT),
130 CONFIG("dump_speed", dump_speed, BOOL),
131 CONFIG("multi_read_count", multi_read_count, INT),
132 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
133 CONFIG("lock_pages", lock_pages, BOOL),
134 CONFIG("icmp_rate", icmp_rate, INT),
135 CONFIG("packet_limit", max_packets, INT),
136 CONFIG("cluster_address", cluster_address, IPv4),
137 CONFIG("cluster_interface", cluster_interface, STRING),
138 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
139 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
140 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
141 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
142 { NULL, 0, 0, 0 },
143 };
144
145 static char *plugin_functions[] = {
146 NULL,
147 "plugin_pre_auth",
148 "plugin_post_auth",
149 "plugin_packet_rx",
150 "plugin_packet_tx",
151 "plugin_timer",
152 "plugin_new_session",
153 "plugin_kill_session",
154 "plugin_control",
155 "plugin_radius_response",
156 "plugin_radius_reset",
157 "plugin_become_master",
158 "plugin_new_session_master",
159 };
160
161 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
162
163 // Counters for shutdown sessions
164 static sessiont shut_acct[8192];
165 static sessionidt shut_acct_n = 0;
166
167 tunnelt *tunnel = NULL; // Array of tunnel structures.
168 sessiont *session = NULL; // Array of session structures.
169 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
170 radiust *radius = NULL; // Array of radius structures.
171 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
172 ip_filtert *ip_filters = NULL; // Array of named filters.
173 static controlt *controlfree = 0;
174 struct Tstats *_statistics = NULL;
175 #ifdef RINGBUFFER
176 struct Tringbuffer *ringbuffer = NULL;
177 #endif
178
179 static void cache_ipmap(in_addr_t ip, int s);
180 static void uncache_ipmap(in_addr_t ip);
181 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
182 static void free_ip_address(sessionidt s);
183 static void dump_acct_info(int all);
184 static void sighup_handler(int sig);
185 static void sigalrm_handler(int sig);
186 static void shutdown_handler(int sig);
187 static void sigchild_handler(int sig);
188 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
189 static void update_config(void);
190 static void read_config_file(void);
191 static void initplugins(void);
192 static int add_plugin(char *plugin_name);
193 static int remove_plugin(char *plugin_name);
194 static void plugins_done(void);
195 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
196 static tunnelidt new_tunnel(void);
197 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
198
199 // on slaves, alow BGP to withdraw cleanly before exiting
200 #define QUIT_DELAY 5
201
202 // quit actions (master)
203 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
204 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
205
206 // return internal time (10ths since process startup), set f if given
207 static clockt now(double *f)
208 {
209 struct timeval t;
210 gettimeofday(&t, 0);
211 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
212 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
213 }
214
215 // work out a retry time based on try number
216 // This is a straight bounded exponential backoff.
217 // Maximum re-try time is 32 seconds. (2^5).
218 clockt backoff(uint8_t try)
219 {
220 if (try > 5) try = 5; // max backoff
221 return now(NULL) + 10 * (1 << try);
222 }
223
224
225 //
226 // Log a debug message. Typically called via the LOG macro
227 //
228 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
229 {
230 static char message[65536] = {0};
231 va_list ap;
232
233 #ifdef RINGBUFFER
234 if (ringbuffer)
235 {
236 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
237 ringbuffer->tail = 0;
238 if (ringbuffer->tail == ringbuffer->head)
239 if (++ringbuffer->head >= RINGBUFFER_SIZE)
240 ringbuffer->head = 0;
241
242 ringbuffer->buffer[ringbuffer->tail].level = level;
243 ringbuffer->buffer[ringbuffer->tail].session = s;
244 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
245 va_start(ap, format);
246 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
247 va_end(ap);
248 }
249 #endif
250
251 if (config->debug < level) return;
252
253 va_start(ap, format);
254 vsnprintf(message, sizeof(message), format, ap);
255
256 if (log_stream)
257 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
258 else if (syslog_log)
259 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
260
261 va_end(ap);
262 }
263
264 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
265 {
266 int i, j;
267 const uint8_t *d = data;
268
269 if (config->debug < level) return;
270
271 // No support for _log_hex to syslog
272 if (log_stream)
273 {
274 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
275 setvbuf(log_stream, NULL, _IOFBF, 16384);
276
277 for (i = 0; i < maxsize; )
278 {
279 fprintf(log_stream, "%4X: ", i);
280 for (j = i; j < maxsize && j < (i + 16); j++)
281 {
282 fprintf(log_stream, "%02X ", d[j]);
283 if (j == i + 7)
284 fputs(": ", log_stream);
285 }
286
287 for (; j < i + 16; j++)
288 {
289 fputs(" ", log_stream);
290 if (j == i + 7)
291 fputs(": ", log_stream);
292 }
293
294 fputs(" ", log_stream);
295 for (j = i; j < maxsize && j < (i + 16); j++)
296 {
297 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
298 fputc(d[j], log_stream);
299 else
300 fputc('.', log_stream);
301
302 if (j == i + 7)
303 fputs(" ", log_stream);
304 }
305
306 i = j;
307 fputs("\n", log_stream);
308 }
309
310 fflush(log_stream);
311 setbuf(log_stream, NULL);
312 }
313 }
314
315 // update a counter, accumulating 2^32 wraps
316 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
317 {
318 uint32_t new = *counter + delta;
319 if (new < *counter)
320 (*wrap)++;
321
322 *counter = new;
323 }
324
325 // initialise the random generator
326 static void initrandom(char *source)
327 {
328 static char path[sizeof(config->random_device)] = "*undefined*";
329
330 // reinitialise only if we are forced to do so or if the config has changed
331 if (source && !strncmp(path, source, sizeof(path)))
332 return;
333
334 // close previous source, if any
335 if (rand_fd >= 0)
336 close(rand_fd);
337
338 rand_fd = -1;
339
340 if (source)
341 {
342 // register changes
343 snprintf(path, sizeof(path), "%s", source);
344
345 if (*path == '/')
346 {
347 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
348 if (rand_fd < 0)
349 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
350 path, strerror(errno));
351 }
352 }
353 }
354
355 // fill buffer with random data
356 void random_data(uint8_t *buf, int len)
357 {
358 int n = 0;
359
360 CSTAT(random_data);
361 if (rand_fd >= 0)
362 {
363 n = read(rand_fd, buf, len);
364 if (n >= len) return;
365 if (n < 0)
366 {
367 if (errno != EAGAIN)
368 {
369 LOG(0, 0, 0, "Error reading from random source: %s\n",
370 strerror(errno));
371
372 // fall back to rand()
373 initrandom(NULL);
374 }
375
376 n = 0;
377 }
378 }
379
380 // append missing data
381 while (n < len)
382 // not using the low order bits from the prng stream
383 buf[n++] = (rand() >> 4) & 0xff;
384 }
385
386 // Add a route
387 //
388 // This adds it to the routing table, advertises it
389 // via BGP if enabled, and stuffs it into the
390 // 'sessionbyip' cache.
391 //
392 // 'ip' and 'mask' must be in _host_ order.
393 //
394 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
395 {
396 struct rtentry r;
397 int i;
398
399 if (!mask) mask = 0xffffffff;
400
401 ip &= mask; // Force the ip to be the first one in the route.
402
403 memset(&r, 0, sizeof(r));
404 r.rt_dev = config->tundevice;
405 r.rt_dst.sa_family = AF_INET;
406 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
407 r.rt_gateway.sa_family = AF_INET;
408 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
409 r.rt_genmask.sa_family = AF_INET;
410 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
411 r.rt_flags = (RTF_UP | RTF_STATIC);
412 if (gw)
413 r.rt_flags |= RTF_GATEWAY;
414 else if (mask == 0xffffffff)
415 r.rt_flags |= RTF_HOST;
416
417 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
418 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
419 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
420
421 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
422 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
423
424 #ifdef BGP
425 if (add)
426 bgp_add_route(htonl(ip), htonl(mask));
427 else
428 bgp_del_route(htonl(ip), htonl(mask));
429 #endif /* BGP */
430
431 // Add/Remove the IPs to the 'sessionbyip' cache.
432 // Note that we add the zero address in the case of
433 // a network route. Roll on CIDR.
434
435 // Note that 's == 0' implies this is the address pool.
436 // We still cache it here, because it will pre-fill
437 // the malloc'ed tree.
438
439 if (s)
440 {
441 if (!add) // Are we deleting a route?
442 s = 0; // Caching the session as '0' is the same as uncaching.
443
444 for (i = ip; (i&mask) == (ip&mask) ; ++i)
445 cache_ipmap(i, s);
446 }
447 }
448
449 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
450 {
451 struct in6_rtmsg rt;
452 char ipv6addr[INET6_ADDRSTRLEN];
453
454 if (ifr6fd < 0)
455 {
456 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
457 return;
458 }
459
460 memset(&rt, 0, sizeof(rt));
461
462 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
463 rt.rtmsg_dst_len = prefixlen;
464 rt.rtmsg_metric = 1;
465 rt.rtmsg_flags = RTF_UP;
466 rt.rtmsg_ifindex = tunidx;
467
468 LOG(1, 0, 0, "Route %s %s/%d\n",
469 add ? "add" : "del",
470 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
471 prefixlen);
472
473 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
474 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
475 strerror(errno));
476
477 // FIXME: need to add BGP routing (RFC2858)
478
479 if (s)
480 {
481 if (!add) // Are we deleting a route?
482 s = 0; // Caching the session as '0' is the same as uncaching.
483
484 cache_ipv6map(ip, prefixlen, s);
485 }
486
487 return;
488 }
489
490 // defined in linux/ipv6.h, but tricky to include from user-space
491 // TODO: move routing to use netlink rather than ioctl
492 struct in6_ifreq {
493 struct in6_addr ifr6_addr;
494 __u32 ifr6_prefixlen;
495 unsigned int ifr6_ifindex;
496 };
497
498 //
499 // Set up TUN interface
500 static void inittun(void)
501 {
502 struct ifreq ifr;
503 struct in6_ifreq ifr6;
504 struct sockaddr_in sin = {0};
505 memset(&ifr, 0, sizeof(ifr));
506 ifr.ifr_flags = IFF_TUN;
507
508 tunfd = open(TUNDEVICE, O_RDWR);
509 if (tunfd < 0)
510 { // fatal
511 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
512 exit(1);
513 }
514 {
515 int flags = fcntl(tunfd, F_GETFL, 0);
516 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
517 }
518 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
519 {
520 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
521 exit(1);
522 }
523 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
524 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
525 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
526
527 sin.sin_family = AF_INET;
528 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
529 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
530
531 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
532 {
533 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
534 exit(1);
535 }
536 /* Bump up the qlen to deal with bursts from the network */
537 ifr.ifr_qlen = 1000;
538 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
539 {
540 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
541 exit(1);
542 }
543 ifr.ifr_flags = IFF_UP;
544 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
545 {
546 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
547 exit(1);
548 }
549 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
550 {
551 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
552 exit(1);
553 }
554 tunidx = ifr.ifr_ifindex;
555
556 // Only setup IPv6 on the tun device if we have a configured prefix
557 if (config->ipv6_prefix.s6_addr[0]) {
558 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
559
560 // Link local address is FE80::1
561 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
562 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
563 ifr6.ifr6_addr.s6_addr[1] = 0x80;
564 ifr6.ifr6_addr.s6_addr[15] = 1;
565 ifr6.ifr6_prefixlen = 64;
566 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
567 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
568 {
569 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
570 " %s\n", strerror(errno));
571 }
572
573 // Global address is prefix::1
574 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
575 ifr6.ifr6_addr = config->ipv6_prefix;
576 ifr6.ifr6_addr.s6_addr[15] = 1;
577 ifr6.ifr6_prefixlen = 64;
578 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
579 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
580 {
581 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
582 strerror(errno));
583 }
584 }
585 }
586
587 // set up UDP ports
588 static void initudp(void)
589 {
590 int on = 1;
591 struct sockaddr_in addr;
592
593 // Tunnel
594 memset(&addr, 0, sizeof(addr));
595 addr.sin_family = AF_INET;
596 addr.sin_port = htons(L2TPPORT);
597 addr.sin_addr.s_addr = config->bind_address;
598 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
599 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
600 {
601 int flags = fcntl(udpfd, F_GETFL, 0);
602 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
603 }
604 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
605 {
606 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
607 exit(1);
608 }
609
610 // Control
611 memset(&addr, 0, sizeof(addr));
612 addr.sin_family = AF_INET;
613 addr.sin_port = htons(NSCTL_PORT);
614 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
615 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
616 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
617 {
618 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
619 exit(1);
620 }
621
622 // Dynamic Authorization Extensions to RADIUS
623 memset(&addr, 0, sizeof(addr));
624 addr.sin_family = AF_INET;
625 addr.sin_port = htons(config->radius_dae_port);
626 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
627 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
628 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
629 {
630 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
631 exit(1);
632 }
633
634 // Intercept
635 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
636 }
637
638 //
639 // Find session by IP, < 1 for not found
640 //
641 // Confusingly enough, this 'ip' must be
642 // in _network_ order. This being the common
643 // case when looking it up from IP packet headers.
644 //
645 // We actually use this cache for two things.
646 // #1. For used IP addresses, this maps to the
647 // session ID that it's used by.
648 // #2. For un-used IP addresses, this maps to the
649 // index into the pool table that contains that
650 // IP address.
651 //
652
653 static int lookup_ipmap(in_addr_t ip)
654 {
655 uint8_t *a = (uint8_t *) &ip;
656 uint8_t **d = (uint8_t **) ip_hash;
657
658 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
659 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
660 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
661
662 return (int) (intptr_t) d[(size_t) *a];
663 }
664
665 static int lookup_ipv6map(struct in6_addr ip)
666 {
667 struct ipv6radix *curnode;
668 int i;
669 int s;
670 char ipv6addr[INET6_ADDRSTRLEN];
671
672 curnode = &ipv6_hash[ip.s6_addr[0]];
673 i = 1;
674 s = curnode->sess;
675
676 while (s == 0 && i < 15 && curnode->branch != NULL)
677 {
678 curnode = &curnode->branch[ip.s6_addr[i]];
679 s = curnode->sess;
680 i++;
681 }
682
683 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
684 inet_ntop(AF_INET6, &ip, ipv6addr,
685 INET6_ADDRSTRLEN),
686 s);
687
688 return s;
689 }
690
691 sessionidt sessionbyip(in_addr_t ip)
692 {
693 int s = lookup_ipmap(ip);
694 CSTAT(sessionbyip);
695
696 if (s > 0 && s < MAXSESSION && session[s].opened)
697 return (sessionidt) s;
698
699 return 0;
700 }
701
702 sessionidt sessionbyipv6(struct in6_addr ip)
703 {
704 int s;
705 CSTAT(sessionbyipv6);
706
707 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
708 (ip.s6_addr[0] == 0xFE &&
709 ip.s6_addr[1] == 0x80 &&
710 ip.s6_addr16[1] == 0 &&
711 ip.s6_addr16[2] == 0 &&
712 ip.s6_addr16[3] == 0)) {
713 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
714 } else {
715 s = lookup_ipv6map(ip);
716 }
717
718 if (s > 0 && s < MAXSESSION && session[s].opened)
719 return s;
720
721 return 0;
722 }
723
724 //
725 // Take an IP address in HOST byte order and
726 // add it to the sessionid by IP cache.
727 //
728 // (It's actually cached in network order)
729 //
730 static void cache_ipmap(in_addr_t ip, int s)
731 {
732 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
733 uint8_t *a = (uint8_t *) &nip;
734 uint8_t **d = (uint8_t **) ip_hash;
735 int i;
736
737 for (i = 0; i < 3; i++)
738 {
739 if (!d[(size_t) a[i]])
740 {
741 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
742 return;
743 }
744
745 d = (uint8_t **) d[(size_t) a[i]];
746 }
747
748 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
749
750 if (s > 0)
751 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
752
753 else if (s == 0)
754 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
755 // else a map to an ip pool index.
756 }
757
758 static void uncache_ipmap(in_addr_t ip)
759 {
760 cache_ipmap(ip, 0); // Assign it to the NULL session.
761 }
762
763 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
764 {
765 int i;
766 int bytes;
767 struct ipv6radix *curnode;
768 char ipv6addr[INET6_ADDRSTRLEN];
769
770 curnode = &ipv6_hash[ip.s6_addr[0]];
771
772 bytes = prefixlen >> 3;
773 i = 1;
774 while (i < bytes) {
775 if (curnode->branch == NULL)
776 {
777 if (!(curnode->branch = calloc(256,
778 sizeof (struct ipv6radix))))
779 return;
780 }
781 curnode = &curnode->branch[ip.s6_addr[i]];
782 i++;
783 }
784
785 curnode->sess = s;
786
787 if (s > 0)
788 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
789 inet_ntop(AF_INET6, &ip, ipv6addr,
790 INET6_ADDRSTRLEN),
791 prefixlen);
792 else if (s == 0)
793 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
794 inet_ntop(AF_INET6, &ip, ipv6addr,
795 INET6_ADDRSTRLEN),
796 prefixlen);
797 }
798
799 //
800 // CLI list to dump current ipcache.
801 //
802 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
803 {
804 char **d = (char **) ip_hash, **e, **f, **g;
805 int i, j, k, l;
806 int count = 0;
807
808 if (CLI_HELP_REQUESTED)
809 return CLI_HELP_NO_ARGS;
810
811 cli_print(cli, "%7s %s", "Sess#", "IP Address");
812
813 for (i = 0; i < 256; ++i)
814 {
815 if (!d[i])
816 continue;
817 e = (char **) d[i];
818 for (j = 0; j < 256; ++j)
819 {
820 if (!e[j])
821 continue;
822 f = (char **) e[j];
823 for (k = 0; k < 256; ++k)
824 {
825 if (!f[k])
826 continue;
827 g = (char **)f[k];
828 for (l = 0; l < 256; ++l)
829 {
830 if (!g[l])
831 continue;
832 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
833 ++count;
834 }
835 }
836 }
837 }
838 cli_print(cli, "%d entries in cache", count);
839 return CLI_OK;
840 }
841
842
843 // Find session by username, 0 for not found
844 // walled garden users aren't authenticated, so the username is
845 // reasonably useless. Ignore them to avoid incorrect actions
846 //
847 // This is VERY inefficent. Don't call it often. :)
848 //
849 sessionidt sessionbyuser(char *username)
850 {
851 int s;
852 CSTAT(sessionbyuser);
853
854 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
855 {
856 if (!session[s].opened)
857 continue;
858
859 if (session[s].walled_garden)
860 continue; // Skip walled garden users.
861
862 if (!strncmp(session[s].user, username, 128))
863 return s;
864
865 }
866 return 0; // Not found.
867 }
868
869 void send_garp(in_addr_t ip)
870 {
871 int s;
872 struct ifreq ifr;
873 uint8_t mac[6];
874
875 s = socket(PF_INET, SOCK_DGRAM, 0);
876 if (s < 0)
877 {
878 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
879 return;
880 }
881 memset(&ifr, 0, sizeof(ifr));
882 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
883 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
884 {
885 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
886 close(s);
887 return;
888 }
889 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
890 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
891 {
892 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
893 close(s);
894 return;
895 }
896 close(s);
897 sendarp(ifr.ifr_ifindex, mac, ip);
898 }
899
900 static sessiont *sessiontbysessionidt(sessionidt s)
901 {
902 if (!s || s >= MAXSESSION) return NULL;
903 return &session[s];
904 }
905
906 static sessionidt sessionidtbysessiont(sessiont *s)
907 {
908 sessionidt val = s-session;
909 if (s < session || val >= MAXSESSION) return 0;
910 return val;
911 }
912
913 // actually send a control message for a specific tunnel
914 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
915 {
916 struct sockaddr_in addr;
917
918 CSTAT(tunnelsend);
919
920 if (!t)
921 {
922 static int backtrace_count = 0;
923 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
924 STAT(tunnel_tx_errors);
925 log_backtrace(backtrace_count, 5)
926 return;
927 }
928
929 if (!tunnel[t].ip)
930 {
931 static int backtrace_count = 0;
932 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
933 log_backtrace(backtrace_count, 5)
934 STAT(tunnel_tx_errors);
935 return;
936 }
937
938 memset(&addr, 0, sizeof(addr));
939 addr.sin_family = AF_INET;
940 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
941 addr.sin_port = htons(tunnel[t].port);
942
943 // sequence expected, if sequence in message
944 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
945
946 // If this is a control message, deal with retries
947 if (*buf & 0x80)
948 {
949 tunnel[t].last = time_now; // control message sent
950 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
951 if (tunnel[t].try > 1)
952 {
953 STAT(tunnel_retries);
954 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
955 }
956 }
957
958 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
959 {
960 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
961 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
962 STAT(tunnel_tx_errors);
963 return;
964 }
965
966 LOG_HEX(5, "Send Tunnel Data", buf, l);
967 STAT(tunnel_tx_packets);
968 INC_STAT(tunnel_tx_bytes, l);
969 }
970
971 //
972 // Tiny helper function to write data to
973 // the 'tun' device.
974 //
975 int tun_write(uint8_t * data, int size)
976 {
977 return write(tunfd, data, size);
978 }
979
980 // process outgoing (to tunnel) IP
981 //
982 static void processipout(uint8_t *buf, int len)
983 {
984 sessionidt s;
985 sessiont *sp;
986 tunnelidt t;
987 in_addr_t ip;
988
989 uint8_t *data = buf; // Keep a copy of the originals.
990 int size = len;
991
992 uint8_t b[MAXETHER + 20];
993
994 CSTAT(processipout);
995
996 if (len < MIN_IP_SIZE)
997 {
998 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
999 STAT(tun_rx_errors);
1000 return;
1001 }
1002 if (len >= MAXETHER)
1003 {
1004 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1005 STAT(tun_rx_errors);
1006 return;
1007 }
1008
1009 // Skip the tun header
1010 buf += 4;
1011 len -= 4;
1012
1013 // Got an IP header now
1014 if (*(uint8_t *)(buf) >> 4 != 4)
1015 {
1016 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1017 return;
1018 }
1019
1020 ip = *(uint32_t *)(buf + 16);
1021 if (!(s = sessionbyip(ip)))
1022 {
1023 // Is this a packet for a session that doesn't exist?
1024 static int rate = 0; // Number of ICMP packets we've sent this second.
1025 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1026
1027 if (last != time_now)
1028 {
1029 last = time_now;
1030 rate = 0;
1031 }
1032
1033 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1034 {
1035 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1036 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1037 config->bind_address ? config->bind_address : my_address, buf, len);
1038 }
1039 return;
1040 }
1041 t = session[s].tunnel;
1042 sp = &session[s];
1043
1044 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1045 if (config->max_packets > 0)
1046 {
1047 if (sess_local[s].last_packet_out == TIME)
1048 {
1049 int max = config->max_packets;
1050
1051 // All packets for throttled sessions are handled by the
1052 // master, so further limit by using the throttle rate.
1053 // A bit of a kludge, since throttle rate is in kbps,
1054 // but should still be generous given our average DSL
1055 // packet size is 200 bytes: a limit of 28kbps equates
1056 // to around 180 packets per second.
1057 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1058 max = sp->throttle_out;
1059
1060 if (++sess_local[s].packets_out > max)
1061 {
1062 sess_local[s].packets_dropped++;
1063 return;
1064 }
1065 }
1066 else
1067 {
1068 if (sess_local[s].packets_dropped)
1069 {
1070 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1071 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1072 sess_local[s].packets_dropped, sess_local[s].packets_out,
1073 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1074 sp->user);
1075 }
1076
1077 sess_local[s].last_packet_out = TIME;
1078 sess_local[s].packets_out = 1;
1079 sess_local[s].packets_dropped = 0;
1080 }
1081 }
1082
1083 // run access-list if any
1084 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1085 return;
1086
1087 if (sp->tbf_out)
1088 {
1089 // Are we throttling this session?
1090 if (config->cluster_iam_master)
1091 tbf_queue_packet(sp->tbf_out, data, size);
1092 else
1093 master_throttle_packet(sp->tbf_out, data, size);
1094 return;
1095 }
1096 else if (sp->walled_garden && !config->cluster_iam_master)
1097 {
1098 // We are walled-gardening this
1099 master_garden_packet(s, data, size);
1100 return;
1101 }
1102
1103 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1104
1105 // Add on L2TP header
1106 {
1107 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1108 if (!p) return;
1109 tunnelsend(b, len + (p-b), t); // send it...
1110 }
1111
1112 // Snooping this session, send it to intercept box
1113 if (sp->snoop_ip && sp->snoop_port)
1114 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1115
1116 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1117 sp->cout_delta += len;
1118 sp->pout++;
1119 udp_tx += len;
1120
1121 sess_local[s].cout += len; // To send to master..
1122 sess_local[s].pout++;
1123 }
1124
1125 // process outgoing (to tunnel) IPv6
1126 //
1127 static void processipv6out(uint8_t * buf, int len)
1128 {
1129 sessionidt s;
1130 sessiont *sp;
1131 tunnelidt t;
1132 in_addr_t ip;
1133 struct in6_addr ip6;
1134
1135 uint8_t *data = buf; // Keep a copy of the originals.
1136 int size = len;
1137
1138 uint8_t b[MAXETHER + 20];
1139
1140 CSTAT(processipv6out);
1141
1142 if (len < MIN_IP_SIZE)
1143 {
1144 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1145 STAT(tunnel_tx_errors);
1146 return;
1147 }
1148 if (len >= MAXETHER)
1149 {
1150 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1151 STAT(tunnel_tx_errors);
1152 return;
1153 }
1154
1155 // Skip the tun header
1156 buf += 4;
1157 len -= 4;
1158
1159 // Got an IP header now
1160 if (*(uint8_t *)(buf) >> 4 != 6)
1161 {
1162 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1163 return;
1164 }
1165
1166 ip6 = *(struct in6_addr *)(buf+24);
1167 s = sessionbyipv6(ip6);
1168
1169 if (s == 0)
1170 {
1171 ip = *(uint32_t *)(buf + 32);
1172 s = sessionbyip(ip);
1173 }
1174
1175 if (s == 0)
1176 {
1177 // Is this a packet for a session that doesn't exist?
1178 static int rate = 0; // Number of ICMP packets we've sent this second.
1179 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1180
1181 if (last != time_now)
1182 {
1183 last = time_now;
1184 rate = 0;
1185 }
1186
1187 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1188 {
1189 // FIXME: Should send icmp6 host unreachable
1190 }
1191 return;
1192 }
1193 t = session[s].tunnel;
1194 sp = &session[s];
1195
1196 // FIXME: add DoS prevention/filters?
1197
1198 if (sp->tbf_out)
1199 {
1200 // Are we throttling this session?
1201 if (config->cluster_iam_master)
1202 tbf_queue_packet(sp->tbf_out, data, size);
1203 else
1204 master_throttle_packet(sp->tbf_out, data, size);
1205 return;
1206 }
1207 else if (sp->walled_garden && !config->cluster_iam_master)
1208 {
1209 // We are walled-gardening this
1210 master_garden_packet(s, data, size);
1211 return;
1212 }
1213
1214 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1215
1216 // Add on L2TP header
1217 {
1218 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1219 if (!p) return;
1220 tunnelsend(b, len + (p-b), t); // send it...
1221 }
1222
1223 // Snooping this session, send it to intercept box
1224 if (sp->snoop_ip && sp->snoop_port)
1225 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1226
1227 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1228 sp->cout_delta += len;
1229 sp->pout++;
1230 udp_tx += len;
1231
1232 sess_local[s].cout += len; // To send to master..
1233 sess_local[s].pout++;
1234 }
1235
1236 //
1237 // Helper routine for the TBF filters.
1238 // Used to send queued data in to the user!
1239 //
1240 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1241 {
1242 sessiont *sp;
1243 tunnelidt t;
1244 in_addr_t ip;
1245
1246 uint8_t b[MAXETHER + 20];
1247
1248 if (len < 0 || len > MAXETHER)
1249 {
1250 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1251 return;
1252 }
1253
1254 // Skip the tun header
1255 buf += 4;
1256 len -= 4;
1257
1258 ip = *(in_addr_t *)(buf + 16);
1259
1260 if (!session[s].ip)
1261 return;
1262
1263 t = session[s].tunnel;
1264 sp = &session[s];
1265
1266 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1267
1268 // Add on L2TP header
1269 {
1270 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1271 if (!p) return;
1272 tunnelsend(b, len + (p-b), t); // send it...
1273 }
1274
1275 // Snooping this session.
1276 if (sp->snoop_ip && sp->snoop_port)
1277 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1278
1279 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1280 sp->cout_delta += len;
1281 sp->pout++;
1282 udp_tx += len;
1283
1284 sess_local[s].cout += len; // To send to master..
1285 sess_local[s].pout++;
1286 }
1287
1288 // add an AVP (16 bit)
1289 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1290 {
1291 uint16_t l = (m ? 0x8008 : 0x0008);
1292 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1293 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1294 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1295 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1296 c->length += 8;
1297 }
1298
1299 // add an AVP (32 bit)
1300 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1301 {
1302 uint16_t l = (m ? 0x800A : 0x000A);
1303 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1304 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1305 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1306 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1307 c->length += 10;
1308 }
1309
1310 // add an AVP (string)
1311 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1312 {
1313 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1314 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1315 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1316 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1317 memcpy(c->buf + c->length + 6, val, strlen(val));
1318 c->length += 6 + strlen(val);
1319 }
1320
1321 // add a binary AVP
1322 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1323 {
1324 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1325 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1326 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1327 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1328 memcpy(c->buf + c->length + 6, val, len);
1329 c->length += 6 + len;
1330 }
1331
1332 // new control connection
1333 static controlt *controlnew(uint16_t mtype)
1334 {
1335 controlt *c;
1336 if (!controlfree)
1337 c = malloc(sizeof(controlt));
1338 else
1339 {
1340 c = controlfree;
1341 controlfree = c->next;
1342 }
1343 assert(c);
1344 c->next = 0;
1345 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1346 c->length = 12;
1347 control16(c, 0, mtype, 1);
1348 return c;
1349 }
1350
1351 // send zero block if nothing is waiting
1352 // (ZLB send).
1353 static void controlnull(tunnelidt t)
1354 {
1355 uint8_t buf[12];
1356 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1357 return;
1358
1359 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1360 *(uint16_t *) (buf + 2) = htons(12); // length
1361 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1362 *(uint16_t *) (buf + 6) = htons(0); // session
1363 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1364 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1365 tunnelsend(buf, 12, t);
1366 }
1367
1368 // add a control message to a tunnel, and send if within window
1369 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1370 {
1371 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1372 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1373 *(uint16_t *) (c->buf + 6) = htons(far); // session
1374 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1375 tunnel[t].ns++; // advance sequence
1376 // link in message in to queue
1377 if (tunnel[t].controlc)
1378 tunnel[t].controle->next = c;
1379 else
1380 tunnel[t].controls = c;
1381
1382 tunnel[t].controle = c;
1383 tunnel[t].controlc++;
1384
1385 // send now if space in window
1386 if (tunnel[t].controlc <= tunnel[t].window)
1387 {
1388 tunnel[t].try = 0; // first send
1389 tunnelsend(c->buf, c->length, t);
1390 }
1391 }
1392
1393 //
1394 // Throttle or Unthrottle a session
1395 //
1396 // Throttle the data from/to through a session to no more than
1397 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1398 // user).
1399 //
1400 // If either value is -1, the current value is retained for that
1401 // direction.
1402 //
1403 void throttle_session(sessionidt s, int rate_in, int rate_out)
1404 {
1405 if (!session[s].opened)
1406 return; // No-one home.
1407
1408 if (!*session[s].user)
1409 return; // User not logged in
1410
1411 if (rate_in >= 0)
1412 {
1413 int bytes = rate_in * 1024 / 8; // kbits to bytes
1414 if (session[s].tbf_in)
1415 free_tbf(session[s].tbf_in);
1416
1417 if (rate_in > 0)
1418 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1419 else
1420 session[s].tbf_in = 0;
1421
1422 session[s].throttle_in = rate_in;
1423 }
1424
1425 if (rate_out >= 0)
1426 {
1427 int bytes = rate_out * 1024 / 8;
1428 if (session[s].tbf_out)
1429 free_tbf(session[s].tbf_out);
1430
1431 if (rate_out > 0)
1432 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1433 else
1434 session[s].tbf_out = 0;
1435
1436 session[s].throttle_out = rate_out;
1437 }
1438 }
1439
1440 // add/remove filters from session (-1 = no change)
1441 void filter_session(sessionidt s, int filter_in, int filter_out)
1442 {
1443 if (!session[s].opened)
1444 return; // No-one home.
1445
1446 if (!*session[s].user)
1447 return; // User not logged in
1448
1449 // paranoia
1450 if (filter_in > MAXFILTER) filter_in = -1;
1451 if (filter_out > MAXFILTER) filter_out = -1;
1452 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1453 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1454
1455 if (filter_in >= 0)
1456 {
1457 if (session[s].filter_in)
1458 ip_filters[session[s].filter_in - 1].used--;
1459
1460 if (filter_in > 0)
1461 ip_filters[filter_in - 1].used++;
1462
1463 session[s].filter_in = filter_in;
1464 }
1465
1466 if (filter_out >= 0)
1467 {
1468 if (session[s].filter_out)
1469 ip_filters[session[s].filter_out - 1].used--;
1470
1471 if (filter_out > 0)
1472 ip_filters[filter_out - 1].used++;
1473
1474 session[s].filter_out = filter_out;
1475 }
1476 }
1477
1478 // start tidy shutdown of session
1479 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1480 {
1481 int walled_garden = session[s].walled_garden;
1482
1483
1484 CSTAT(sessionshutdown);
1485
1486 if (!session[s].opened)
1487 {
1488 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1489 return; // not a live session
1490 }
1491
1492 if (!session[s].die)
1493 {
1494 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1495 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1496 run_plugins(PLUGIN_KILL_SESSION, &data);
1497 }
1498
1499 if (session[s].ip && !walled_garden && !session[s].die)
1500 {
1501 // RADIUS Stop message
1502 uint16_t r = radiusnew(s);
1503 if (r)
1504 {
1505 // stop, if not already trying
1506 if (radius[r].state != RADIUSSTOP)
1507 radiussend(r, RADIUSSTOP);
1508 }
1509 else
1510 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1511
1512 // Save counters to dump to accounting file
1513 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1514 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1515 }
1516
1517 if (session[s].ip)
1518 { // IP allocated, clear and unroute
1519 int r;
1520 int routed = 0;
1521 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1522 {
1523 if ((session[s].ip & session[s].route[r].mask) ==
1524 (session[s].route[r].ip & session[s].route[r].mask))
1525 routed++;
1526
1527 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1528 session[s].route[r].ip = 0;
1529 }
1530
1531 if (session[s].ip_pool_index == -1) // static ip
1532 {
1533 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1534 session[s].ip = 0;
1535 }
1536 else
1537 free_ip_address(s);
1538
1539 // unroute IPv6, if setup
1540 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1541 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1542 }
1543
1544 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1545 throttle_session(s, 0, 0);
1546
1547 if (result)
1548 { // Send CDN
1549 controlt *c = controlnew(14); // sending CDN
1550 if (error)
1551 {
1552 uint8_t buf[4];
1553 *(uint16_t *) buf = htons(result);
1554 *(uint16_t *) (buf+2) = htons(error);
1555 controlb(c, 1, buf, 4, 1);
1556 }
1557 else
1558 control16(c, 1, result, 1);
1559
1560 control16(c, 14, s, 1); // assigned session (our end)
1561 controladd(c, session[s].far, session[s].tunnel); // send the message
1562 }
1563
1564 if (!session[s].die)
1565 session[s].die = TIME + 150; // Clean up in 15 seconds
1566
1567 // update filter refcounts
1568 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1569 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1570
1571 // clear PPP state
1572 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1573 sess_local[s].lcp.restart = 0;
1574 sess_local[s].ipcp.restart = 0;
1575 sess_local[s].ipv6cp.restart = 0;
1576 sess_local[s].ccp.restart = 0;
1577
1578 cluster_send_session(s);
1579 }
1580
1581 void sendipcp(sessionidt s, tunnelidt t)
1582 {
1583 uint8_t buf[MAXCONTROL];
1584 uint8_t *q;
1585
1586 CSTAT(sendipcp);
1587
1588 if (!session[s].unique_id)
1589 {
1590 if (!++last_id) ++last_id; // skip zero
1591 session[s].unique_id = last_id;
1592 }
1593
1594 q = makeppp(buf,sizeof(buf), 0, 0, s, t, PPPIPCP);
1595 if (!q) return;
1596
1597 *q = ConfigReq;
1598 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1599 *(uint16_t *) (q + 2) = htons(10); // packet length
1600 q[4] = 3; // ip address option
1601 q[5] = 6; // option length
1602 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1603 config->bind_address ? config->bind_address :
1604 my_address; // send my IP
1605
1606 tunnelsend(buf, 10 + (q - buf), t); // send it
1607 }
1608
1609 void sendipv6cp(sessionidt s, tunnelidt t)
1610 {
1611 uint8_t buf[MAXCONTROL];
1612 uint8_t *q;
1613
1614 CSTAT(sendipv6cp);
1615
1616 q = makeppp(buf,sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1617 if (!q) return;
1618
1619 *q = ConfigReq;
1620 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1621 // only send one type
1622 // of request
1623 *(uint16_t *) (q + 2) = htons(14);
1624 q[4] = 1; // interface identifier option
1625 q[5] = 10; // option length
1626 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1627 *(uint32_t *) (q + 10) = 0;
1628 q[13] = 1;
1629
1630 tunnelsend(buf, 14 + (q - buf), t); // send it
1631 }
1632
1633 static void sessionclear(sessionidt s)
1634 {
1635 memset(&session[s], 0, sizeof(session[s]));
1636 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1637 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1638
1639 session[s].tunnel = T_FREE; // Mark it as free.
1640 session[s].next = sessionfree;
1641 sessionfree = s;
1642 }
1643
1644 // kill a session now
1645 void sessionkill(sessionidt s, char *reason)
1646 {
1647
1648 CSTAT(sessionkill);
1649
1650 if (!session[s].opened) // not alive
1651 return;
1652
1653 if (session[s].next)
1654 {
1655 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1656 return;
1657 }
1658
1659 session[s].die = TIME;
1660 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1661 if (sess_local[s].radius)
1662 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1663
1664 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1665 sessionclear(s);
1666 cluster_send_session(s);
1667 }
1668
1669 static void tunnelclear(tunnelidt t)
1670 {
1671 if (!t) return;
1672 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1673 tunnel[t].state = TUNNELFREE;
1674 }
1675
1676 // kill a tunnel now
1677 static void tunnelkill(tunnelidt t, char *reason)
1678 {
1679 sessionidt s;
1680 controlt *c;
1681
1682 CSTAT(tunnelkill);
1683
1684 tunnel[t].state = TUNNELDIE;
1685
1686 // free control messages
1687 while ((c = tunnel[t].controls))
1688 {
1689 controlt * n = c->next;
1690 tunnel[t].controls = n;
1691 tunnel[t].controlc--;
1692 c->next = controlfree;
1693 controlfree = c;
1694 }
1695 // kill sessions
1696 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1697 if (session[s].tunnel == t)
1698 sessionkill(s, reason);
1699
1700 // free tunnel
1701 tunnelclear(t);
1702 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1703 cli_tunnel_actions[t].action = 0;
1704 cluster_send_tunnel(t);
1705 }
1706
1707 // shut down a tunnel cleanly
1708 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1709 {
1710 sessionidt s;
1711
1712 CSTAT(tunnelshutdown);
1713
1714 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1715 {
1716 // never set up, can immediately kill
1717 tunnelkill(t, reason);
1718 return;
1719 }
1720 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1721
1722 // close session
1723 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1724 if (session[s].tunnel == t)
1725 sessionshutdown(s, reason, 0, 0);
1726
1727 tunnel[t].state = TUNNELDIE;
1728 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1729 cluster_send_tunnel(t);
1730 // TBA - should we wait for sessions to stop?
1731 if (result)
1732 {
1733 controlt *c = controlnew(4); // sending StopCCN
1734 if (error)
1735 {
1736 uint8_t buf[64];
1737 int l = 4;
1738 *(uint16_t *) buf = htons(result);
1739 *(uint16_t *) (buf+2) = htons(error);
1740 if (msg)
1741 {
1742 int m = strlen(msg);
1743 if (m + 4 > sizeof(buf))
1744 m = sizeof(buf) - 4;
1745
1746 memcpy(buf+4, msg, m);
1747 l += m;
1748 }
1749
1750 controlb(c, 1, buf, l, 1);
1751 }
1752 else
1753 control16(c, 1, result, 1);
1754
1755 control16(c, 9, t, 1); // assigned tunnel (our end)
1756 controladd(c, 0, t); // send the message
1757 }
1758 }
1759
1760 // read and process packet on tunnel (UDP)
1761 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1762 {
1763 uint8_t *chapresponse = NULL;
1764 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1765 uint8_t *p = buf + 2;
1766
1767
1768 CSTAT(processudp);
1769
1770 udp_rx += len;
1771 udp_rx_pkt++;
1772 LOG_HEX(5, "UDP Data", buf, len);
1773 STAT(tunnel_rx_packets);
1774 INC_STAT(tunnel_rx_bytes, len);
1775 if (len < 6)
1776 {
1777 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1778 STAT(tunnel_rx_errors);
1779 return;
1780 }
1781 if ((buf[1] & 0x0F) != 2)
1782 {
1783 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1784 STAT(tunnel_rx_errors);
1785 return;
1786 }
1787 if (*buf & 0x40)
1788 { // length
1789 l = ntohs(*(uint16_t *) p);
1790 p += 2;
1791 }
1792 t = ntohs(*(uint16_t *) p);
1793 p += 2;
1794 s = ntohs(*(uint16_t *) p);
1795 p += 2;
1796 if (s >= MAXSESSION)
1797 {
1798 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1799 STAT(tunnel_rx_errors);
1800 return;
1801 }
1802 if (t >= MAXTUNNEL)
1803 {
1804 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1805 STAT(tunnel_rx_errors);
1806 return;
1807 }
1808 if (*buf & 0x08)
1809 { // ns/nr
1810 ns = ntohs(*(uint16_t *) p);
1811 p += 2;
1812 nr = ntohs(*(uint16_t *) p);
1813 p += 2;
1814 }
1815 if (*buf & 0x02)
1816 { // offset
1817 uint16_t o = ntohs(*(uint16_t *) p);
1818 p += o + 2;
1819 }
1820 if ((p - buf) > l)
1821 {
1822 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1823 STAT(tunnel_rx_errors);
1824 return;
1825 }
1826 l -= (p - buf);
1827 if (*buf & 0x80)
1828 { // control
1829 uint16_t message = 0xFFFF; // message type
1830 uint8_t fatal = 0;
1831 uint8_t mandatory = 0;
1832 uint16_t asession = 0; // assigned session
1833 uint32_t amagic = 0; // magic number
1834 uint8_t aflags = 0; // flags from last LCF
1835 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1836 char called[MAXTEL] = ""; // called number
1837 char calling[MAXTEL] = ""; // calling number
1838
1839 if (!config->cluster_iam_master)
1840 {
1841 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1842 return;
1843 }
1844
1845 // control messages must have bits 0x80|0x40|0x08
1846 // (type, length and sequence) set, and bits 0x02|0x01
1847 // (offset and priority) clear
1848 if ((*buf & 0xCB) != 0xC8)
1849 {
1850 LOG(1, s, t, "Bad control header %02X\n", *buf);
1851 STAT(tunnel_rx_errors);
1852 return;
1853 }
1854
1855 // check for duplicate tunnel open message
1856 if (!t && ns == 0)
1857 {
1858 int i;
1859
1860 //
1861 // Is this a duplicate of the first packet? (SCCRQ)
1862 //
1863 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1864 {
1865 if (tunnel[i].state != TUNNELOPENING ||
1866 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1867 tunnel[i].port != ntohs(addr->sin_port) )
1868 continue;
1869 t = i;
1870 LOG(3, s, t, "Duplicate SCCRQ?\n");
1871 break;
1872 }
1873 }
1874
1875 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1876 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1877
1878 // if no tunnel specified, assign one
1879 if (!t)
1880 {
1881 if (!(t = new_tunnel()))
1882 {
1883 LOG(1, 0, 0, "No more tunnels\n");
1884 STAT(tunnel_overflow);
1885 return;
1886 }
1887 tunnelclear(t);
1888 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1889 tunnel[t].port = ntohs(addr->sin_port);
1890 tunnel[t].window = 4; // default window
1891 STAT(tunnel_created);
1892 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1893 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1894 }
1895
1896 // If the 'ns' just received is not the 'nr' we're
1897 // expecting, just send an ack and drop it.
1898 //
1899 // if 'ns' is less, then we got a retransmitted packet.
1900 // if 'ns' is greater than missed a packet. Either way
1901 // we should ignore it.
1902 if (ns != tunnel[t].nr)
1903 {
1904 // is this the sequence we were expecting?
1905 STAT(tunnel_rx_errors);
1906 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1907 t, ns, tunnel[t].nr);
1908
1909 if (l) // Is this not a ZLB?
1910 controlnull(t);
1911 return;
1912 }
1913
1914 // This is used to time out old tunnels
1915 tunnel[t].lastrec = time_now;
1916
1917 // check sequence of this message
1918 {
1919 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1920 // some to clear maybe?
1921 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1922 {
1923 controlt *c = tunnel[t].controls;
1924 tunnel[t].controls = c->next;
1925 tunnel[t].controlc--;
1926 c->next = controlfree;
1927 controlfree = c;
1928 skip--;
1929 tunnel[t].try = 0; // we have progress
1930 }
1931
1932 // receiver advance (do here so quoted correctly in any sends below)
1933 if (l) tunnel[t].nr = (ns + 1);
1934 if (skip < 0) skip = 0;
1935 if (skip < tunnel[t].controlc)
1936 {
1937 // some control packets can now be sent that were previous stuck out of window
1938 int tosend = tunnel[t].window - skip;
1939 controlt *c = tunnel[t].controls;
1940 while (c && skip)
1941 {
1942 c = c->next;
1943 skip--;
1944 }
1945 while (c && tosend)
1946 {
1947 tunnel[t].try = 0; // first send
1948 tunnelsend(c->buf, c->length, t);
1949 c = c->next;
1950 tosend--;
1951 }
1952 }
1953 if (!tunnel[t].controlc)
1954 tunnel[t].retry = 0; // caught up
1955 }
1956 if (l)
1957 { // if not a null message
1958 int result = 0;
1959 int error = 0;
1960 char *msg = 0;
1961
1962 // process AVPs
1963 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1964 {
1965 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1966 uint8_t *b = p;
1967 uint8_t flags = *p;
1968 uint16_t mtype;
1969 if (n > l)
1970 {
1971 LOG(1, s, t, "Invalid length in AVP\n");
1972 STAT(tunnel_rx_errors);
1973 return;
1974 }
1975 p += n; // next
1976 l -= n;
1977 if (flags & 0x3C) // reserved bits, should be clear
1978 {
1979 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1980 fatal = flags;
1981 result = 2; // general error
1982 error = 3; // reserved field non-zero
1983 msg = 0;
1984 continue; // next
1985 }
1986 b += 2;
1987 if (*(uint16_t *) (b))
1988 {
1989 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1990 fatal = flags;
1991 result = 2; // general error
1992 error = 6; // generic vendor-specific error
1993 msg = "unsupported vendor-specific";
1994 continue; // next
1995 }
1996 b += 2;
1997 mtype = ntohs(*(uint16_t *) (b));
1998 b += 2;
1999 n -= 6;
2000
2001 if (flags & 0x40)
2002 {
2003 uint16_t orig_len;
2004
2005 // handle hidden AVPs
2006 if (!*config->l2tpsecret)
2007 {
2008 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2009 fatal = flags;
2010 result = 2; // general error
2011 error = 6; // generic vendor-specific error
2012 msg = "secret not specified";
2013 continue;
2014 }
2015 if (!session[s].random_vector_length)
2016 {
2017 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2018 fatal = flags;
2019 result = 2; // general error
2020 error = 6; // generic
2021 msg = "no random vector";
2022 continue;
2023 }
2024 if (n < 8)
2025 {
2026 LOG(2, s, t, "Short hidden AVP.\n");
2027 fatal = flags;
2028 result = 2; // general error
2029 error = 2; // length is wrong
2030 msg = 0;
2031 continue;
2032 }
2033
2034 // Unhide the AVP
2035 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2036
2037 orig_len = ntohs(*(uint16_t *) b);
2038 if (orig_len > n + 2)
2039 {
2040 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2041 orig_len, n);
2042
2043 fatal = flags;
2044 result = 2; // general error
2045 error = 2; // length is wrong
2046 msg = 0;
2047 continue;
2048 }
2049
2050 b += 2;
2051 n = orig_len;
2052 }
2053
2054 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2055 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2056
2057 switch (mtype)
2058 {
2059 case 0: // message type
2060 message = ntohs(*(uint16_t *) b);
2061 mandatory = flags & 0x80;
2062 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2063 break;
2064 case 1: // result code
2065 {
2066 uint16_t rescode = ntohs(*(uint16_t *) b);
2067 const char* resdesc = "(unknown)";
2068 if (message == 4)
2069 { /* StopCCN */
2070 resdesc = l2tp_stopccn_result_code(rescode);
2071 }
2072 else if (message == 14)
2073 { /* CDN */
2074 resdesc = l2tp_cdn_result_code(rescode);
2075 }
2076
2077 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2078 if (n >= 4)
2079 {
2080 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2081 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2082 }
2083 if (n > 4)
2084 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2085
2086 break;
2087 }
2088 break;
2089 case 2: // protocol version
2090 {
2091 version = ntohs(*(uint16_t *) (b));
2092 LOG(4, s, t, " Protocol version = %d\n", version);
2093 if (version && version != 0x0100)
2094 { // allow 0.0 and 1.0
2095 LOG(1, s, t, " Bad protocol version %04X\n", version);
2096 fatal = flags;
2097 result = 5; // unspported protocol version
2098 error = 0x0100; // supported version
2099 msg = 0;
2100 continue; // next
2101 }
2102 }
2103 break;
2104 case 3: // framing capabilities
2105 // LOG(4, s, t, "Framing capabilities\n");
2106 break;
2107 case 4: // bearer capabilities
2108 // LOG(4, s, t, "Bearer capabilities\n");
2109 break;
2110 case 5: // tie breaker
2111 // We never open tunnels, so we don't care about tie breakers
2112 // LOG(4, s, t, "Tie breaker\n");
2113 continue;
2114 case 6: // firmware revision
2115 // LOG(4, s, t, "Firmware revision\n");
2116 break;
2117 case 7: // host name
2118 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2119 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2120 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2121 // TBA - to send to RADIUS
2122 break;
2123 case 8: // vendor name
2124 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2125 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2126 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2127 break;
2128 case 9: // assigned tunnel
2129 tunnel[t].far = ntohs(*(uint16_t *) (b));
2130 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2131 break;
2132 case 10: // rx window
2133 tunnel[t].window = ntohs(*(uint16_t *) (b));
2134 if (!tunnel[t].window)
2135 tunnel[t].window = 1; // window of 0 is silly
2136 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2137 break;
2138 case 11: // Challenge
2139 {
2140 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2141 build_chap_response(b, 2, n, &chapresponse);
2142 }
2143 break;
2144 case 13: // Response
2145 // Why did they send a response? We never challenge.
2146 LOG(2, s, t, " received unexpected challenge response\n");
2147 break;
2148
2149 case 14: // assigned session
2150 asession = session[s].far = ntohs(*(uint16_t *) (b));
2151 LOG(4, s, t, " assigned session = %d\n", asession);
2152 break;
2153 case 15: // call serial number
2154 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2155 break;
2156 case 18: // bearer type
2157 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2158 // TBA - for RADIUS
2159 break;
2160 case 19: // framing type
2161 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2162 // TBA
2163 break;
2164 case 21: // called number
2165 memset(called, 0, sizeof(called));
2166 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2167 LOG(4, s, t, " Called <%s>\n", called);
2168 break;
2169 case 22: // calling number
2170 memset(calling, 0, sizeof(calling));
2171 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2172 LOG(4, s, t, " Calling <%s>\n", calling);
2173 break;
2174 case 23: // subtype
2175 break;
2176 case 24: // tx connect speed
2177 if (n == 4)
2178 {
2179 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2180 }
2181 else
2182 {
2183 // AS5300s send connect speed as a string
2184 char tmp[30];
2185 memset(tmp, 0, sizeof(tmp));
2186 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2187 session[s].tx_connect_speed = atol(tmp);
2188 }
2189 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2190 break;
2191 case 38: // rx connect speed
2192 if (n == 4)
2193 {
2194 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2195 }
2196 else
2197 {
2198 // AS5300s send connect speed as a string
2199 char tmp[30];
2200 memset(tmp, 0, sizeof(tmp));
2201 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2202 session[s].rx_connect_speed = atol(tmp);
2203 }
2204 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2205 break;
2206 case 25: // Physical Channel ID
2207 {
2208 uint32_t tmp = ntohl(*(uint32_t *) b);
2209 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2210 break;
2211 }
2212 case 29: // Proxy Authentication Type
2213 {
2214 uint16_t atype = ntohs(*(uint16_t *)b);
2215 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2216 break;
2217 }
2218 case 30: // Proxy Authentication Name
2219 {
2220 char authname[64];
2221 memset(authname, 0, sizeof(authname));
2222 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2223 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2224 authname);
2225 break;
2226 }
2227 case 31: // Proxy Authentication Challenge
2228 {
2229 LOG(4, s, t, " Proxy Auth Challenge\n");
2230 break;
2231 }
2232 case 32: // Proxy Authentication ID
2233 {
2234 uint16_t authid = ntohs(*(uint16_t *)(b));
2235 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2236 break;
2237 }
2238 case 33: // Proxy Authentication Response
2239 LOG(4, s, t, " Proxy Auth Response\n");
2240 break;
2241 case 27: // last sent lcp
2242 { // find magic number
2243 uint8_t *p = b, *e = p + n;
2244 while (p + 1 < e && p[1] && p + p[1] <= e)
2245 {
2246 if (*p == 5 && p[1] == 6) // Magic-Number
2247 amagic = ntohl(*(uint32_t *) (p + 2));
2248 else if (*p == 7) // Protocol-Field-Compression
2249 aflags |= SESSIONPFC;
2250 else if (*p == 8) // Address-and-Control-Field-Compression
2251 aflags |= SESSIONACFC;
2252 p += p[1];
2253 }
2254 }
2255 break;
2256 case 28: // last recv lcp confreq
2257 break;
2258 case 26: // Initial Received LCP CONFREQ
2259 break;
2260 case 39: // seq required - we control it as an LNS anyway...
2261 break;
2262 case 36: // Random Vector
2263 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2264 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2265 if (n > sizeof(session[s].random_vector))
2266 n = sizeof(session[s].random_vector);
2267 memcpy(session[s].random_vector, b, n);
2268 session[s].random_vector_length = n;
2269 break;
2270 default:
2271 {
2272 static char e[] = "unknown AVP 0xXXXX";
2273 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2274 fatal = flags;
2275 result = 2; // general error
2276 error = 8; // unknown mandatory AVP
2277 sprintf((msg = e) + 14, "%04x", mtype);
2278 continue; // next
2279 }
2280 }
2281 }
2282 // process message
2283 if (fatal & 0x80)
2284 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2285 else
2286 switch (message)
2287 {
2288 case 1: // SCCRQ - Start Control Connection Request
2289 tunnel[t].state = TUNNELOPENING;
2290 if (main_quit != QUIT_SHUTDOWN)
2291 {
2292 controlt *c = controlnew(2); // sending SCCRP
2293 control16(c, 2, version, 1); // protocol version
2294 control32(c, 3, 3, 1); // framing
2295 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2296 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2297 control16(c, 9, t, 1); // assigned tunnel
2298 controladd(c, 0, t); // send the resply
2299 }
2300 else
2301 {
2302 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2303 }
2304 break;
2305 case 2: // SCCRP
2306 tunnel[t].state = TUNNELOPEN;
2307 break;
2308 case 3: // SCCN
2309 tunnel[t].state = TUNNELOPEN;
2310 controlnull(t); // ack
2311 break;
2312 case 4: // StopCCN
2313 controlnull(t); // ack
2314 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2315 break;
2316 case 6: // HELLO
2317 controlnull(t); // simply ACK
2318 break;
2319 case 7: // OCRQ
2320 // TBA
2321 break;
2322 case 8: // OCRO
2323 // TBA
2324 break;
2325 case 9: // OCCN
2326 // TBA
2327 break;
2328 case 10: // ICRQ
2329 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2330 {
2331 controlt *c = controlnew(11); // ICRP
2332
2333 s = sessionfree;
2334 sessionfree = session[s].next;
2335 memset(&session[s], 0, sizeof(session[s]));
2336
2337 if (s > config->cluster_highest_sessionid)
2338 config->cluster_highest_sessionid = s;
2339
2340 session[s].opened = time_now;
2341 session[s].tunnel = t;
2342 session[s].far = asession;
2343 session[s].last_packet = time_now;
2344 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2345 control16(c, 14, s, 1); // assigned session
2346 controladd(c, asession, t); // send the reply
2347
2348 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2349 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2350
2351 session[s].ppp.phase = Establish;
2352 session[s].ppp.lcp = Starting;
2353
2354 STAT(session_created);
2355 break;
2356 }
2357
2358 {
2359 controlt *c = controlnew(14); // CDN
2360 if (!sessionfree)
2361 {
2362 STAT(session_overflow);
2363 LOG(1, 0, t, "No free sessions\n");
2364 control16(c, 1, 4, 0); // temporary lack of resources
2365 }
2366 else
2367 control16(c, 1, 2, 7); // shutting down, try another
2368
2369 controladd(c, asession, t); // send the message
2370 }
2371 return;
2372 case 11: // ICRP
2373 // TBA
2374 break;
2375 case 12: // ICCN
2376 if (amagic == 0) amagic = time_now;
2377 session[s].magic = amagic; // set magic number
2378 session[s].l2tp_flags = aflags; // set flags received
2379 controlnull(t); // ack
2380
2381 // start LCP
2382 sendlcp(s, t, config->radius_authprefer);
2383 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2384 sess_local[s].lcp.conf_sent = 1;
2385 sess_local[s].lcp.nak_sent = 0;
2386 sess_local[s].lcp_authtype = config->radius_authprefer;
2387 session[s].ppp.lcp = RequestSent;
2388
2389 break;
2390 case 14: // CDN
2391 controlnull(t); // ack
2392 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2393 break;
2394 case 0xFFFF:
2395 LOG(1, s, t, "Missing message type\n");
2396 break;
2397 default:
2398 STAT(tunnel_rx_errors);
2399 if (mandatory)
2400 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2401 else
2402 LOG(1, s, t, "Unknown message type %d\n", message);
2403 break;
2404 }
2405 if (chapresponse) free(chapresponse);
2406 cluster_send_tunnel(t);
2407 }
2408 else
2409 {
2410 LOG(4, s, t, " Got a ZLB ack\n");
2411 }
2412 }
2413 else
2414 { // data
2415 uint16_t prot;
2416
2417 LOG_HEX(5, "Receive Tunnel Data", p, l);
2418 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2419 { // HDLC address header, discard
2420 p += 2;
2421 l -= 2;
2422 }
2423 if (l < 2)
2424 {
2425 LOG(1, s, t, "Short ppp length %d\n", l);
2426 STAT(tunnel_rx_errors);
2427 return;
2428 }
2429 if (*p & 1)
2430 {
2431 prot = *p++;
2432 l--;
2433 }
2434 else
2435 {
2436 prot = ntohs(*(uint16_t *) p);
2437 p += 2;
2438 l -= 2;
2439 }
2440
2441 if (s && !session[s].opened) // Is something wrong??
2442 {
2443 if (!config->cluster_iam_master)
2444 {
2445 // Pass it off to the master to deal with..
2446 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2447 return;
2448 }
2449
2450
2451 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2452 STAT(tunnel_rx_errors);
2453 return;
2454 }
2455
2456 if (prot == PPPPAP)
2457 {
2458 session[s].last_packet = time_now;
2459 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2460 processpap(s, t, p, l);
2461 }
2462 else if (prot == PPPCHAP)
2463 {
2464 session[s].last_packet = time_now;
2465 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2466 processchap(s, t, p, l);
2467 }
2468 else if (prot == PPPLCP)
2469 {
2470 session[s].last_packet = time_now;
2471 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2472 processlcp(s, t, p, l);
2473 }
2474 else if (prot == PPPIPCP)
2475 {
2476 session[s].last_packet = time_now;
2477 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2478 processipcp(s, t, p, l);
2479 }
2480 else if (prot == PPPIPV6CP)
2481 {
2482 session[s].last_packet = time_now;
2483 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2484 processipv6cp(s, t, p, l);
2485 }
2486 else if (prot == PPPCCP)
2487 {
2488 session[s].last_packet = time_now;
2489 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2490 processccp(s, t, p, l);
2491 }
2492 else if (prot == PPPIP)
2493 {
2494 if (session[s].die)
2495 {
2496 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2497 return; // closing session, PPP not processed
2498 }
2499
2500 session[s].last_packet = time_now;
2501 if (session[s].walled_garden && !config->cluster_iam_master)
2502 {
2503 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2504 return;
2505 }
2506
2507 processipin(s, t, p, l);
2508 }
2509 else if (prot == PPPIPV6)
2510 {
2511 if (!config->ipv6_prefix.s6_addr[0])
2512 {
2513 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2514 return;
2515 }
2516 if (session[s].die)
2517 {
2518 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2519 return; // closing session, PPP not processed
2520 }
2521
2522 session[s].last_packet = time_now;
2523 if (session[s].walled_garden && !config->cluster_iam_master)
2524 {
2525 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2526 return;
2527 }
2528
2529 processipv6in(s, t, p, l);
2530 }
2531 else
2532 {
2533 STAT(tunnel_rx_errors);
2534 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2535 }
2536 }
2537 }
2538
2539 // read and process packet on tun
2540 static void processtun(uint8_t * buf, int len)
2541 {
2542 LOG_HEX(5, "Receive TUN Data", buf, len);
2543 STAT(tun_rx_packets);
2544 INC_STAT(tun_rx_bytes, len);
2545
2546 CSTAT(processtun);
2547
2548 eth_rx_pkt++;
2549 eth_rx += len;
2550 if (len < 22)
2551 {
2552 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2553 STAT(tun_rx_errors);
2554 return;
2555 }
2556
2557 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2558 processipout(buf, len);
2559 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2560 && config->ipv6_prefix.s6_addr[0])
2561 processipv6out(buf, len);
2562
2563 // Else discard.
2564 }
2565
2566 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2567 // that we look at the whole of the tunnel, radius and session tables
2568 // every second
2569 static void regular_cleanups(double period)
2570 {
2571 // Next tunnel, radius and session to check for actions on.
2572 static tunnelidt t = 0;
2573 static int r = 0;
2574 static sessionidt s = 0;
2575
2576 int t_actions = 0;
2577 int r_actions = 0;
2578 int s_actions = 0;
2579
2580 int t_slice;
2581 int r_slice;
2582 int s_slice;
2583
2584 int i;
2585 int a;
2586
2587 // divide up tables into slices based on the last run
2588 t_slice = config->cluster_highest_tunnelid * period;
2589 r_slice = (MAXRADIUS - 1) * period;
2590 s_slice = config->cluster_highest_sessionid * period;
2591
2592 if (t_slice < 1)
2593 t_slice = 1;
2594 else if (t_slice > config->cluster_highest_tunnelid)
2595 t_slice = config->cluster_highest_tunnelid;
2596
2597 if (r_slice < 1)
2598 r_slice = 1;
2599 else if (r_slice > (MAXRADIUS - 1))
2600 r_slice = MAXRADIUS - 1;
2601
2602 if (s_slice < 1)
2603 s_slice = 1;
2604 else if (s_slice > config->cluster_highest_sessionid)
2605 s_slice = config->cluster_highest_sessionid;
2606
2607 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2608
2609 for (i = 0; i < t_slice; i++)
2610 {
2611 t++;
2612 if (t > config->cluster_highest_tunnelid)
2613 t = 1;
2614
2615 // check for expired tunnels
2616 if (tunnel[t].die && tunnel[t].die <= TIME)
2617 {
2618 STAT(tunnel_timeout);
2619 tunnelkill(t, "Expired");
2620 t_actions++;
2621 continue;
2622 }
2623 // check for message resend
2624 if (tunnel[t].retry && tunnel[t].controlc)
2625 {
2626 // resend pending messages as timeout on reply
2627 if (tunnel[t].retry <= TIME)
2628 {
2629 controlt *c = tunnel[t].controls;
2630 uint8_t w = tunnel[t].window;
2631 tunnel[t].try++; // another try
2632 if (tunnel[t].try > 5)
2633 tunnelkill(t, "Timeout on control message"); // game over
2634 else
2635 while (c && w--)
2636 {
2637 tunnelsend(c->buf, c->length, t);
2638 c = c->next;
2639 }
2640
2641 t_actions++;
2642 }
2643 }
2644 // Send hello
2645 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2646 {
2647 controlt *c = controlnew(6); // sending HELLO
2648 controladd(c, 0, t); // send the message
2649 LOG(3, 0, t, "Sending HELLO message\n");
2650 t_actions++;
2651 }
2652
2653 // Check for tunnel changes requested from the CLI
2654 if ((a = cli_tunnel_actions[t].action))
2655 {
2656 cli_tunnel_actions[t].action = 0;
2657 if (a & CLI_TUN_KILL)
2658 {
2659 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2660 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2661 t_actions++;
2662 }
2663 }
2664 }
2665
2666 for (i = 0; i < r_slice; i++)
2667 {
2668 r++;
2669 if (r >= MAXRADIUS)
2670 r = 1;
2671
2672 if (!radius[r].state)
2673 continue;
2674
2675 if (radius[r].retry <= TIME)
2676 {
2677 radiusretry(r);
2678 r_actions++;
2679 }
2680 }
2681
2682 for (i = 0; i < s_slice; i++)
2683 {
2684 s++;
2685 if (s > config->cluster_highest_sessionid)
2686 s = 1;
2687
2688 if (!session[s].opened) // Session isn't in use
2689 continue;
2690
2691 // check for expired sessions
2692 if (session[s].die)
2693 {
2694 if (session[s].die <= TIME)
2695 {
2696 sessionkill(s, "Expired");
2697 s_actions++;
2698 }
2699 continue;
2700 }
2701
2702 // PPP timeouts
2703 if (sess_local[s].lcp.restart <= time_now)
2704 {
2705 int next_state = session[s].ppp.lcp;
2706 switch (session[s].ppp.lcp)
2707 {
2708 case RequestSent:
2709 case AckReceived:
2710 next_state = RequestSent;
2711
2712 case AckSent:
2713 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2714 {
2715 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2716 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2717 sess_local[s].lcp.conf_sent++;
2718 sendlcp(s, t, sess_local[s].lcp_authtype);
2719 change_state(s, lcp, next_state);
2720 }
2721 else
2722 {
2723 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2724 STAT(session_timeout);
2725 }
2726
2727 s_actions++;
2728 }
2729
2730 if (session[s].die)
2731 continue;
2732 }
2733
2734 if (sess_local[s].ipcp.restart <= time_now)
2735 {
2736 int next_state = session[s].ppp.ipcp;
2737 switch (session[s].ppp.ipcp)
2738 {
2739 case RequestSent:
2740 case AckReceived:
2741 next_state = RequestSent;
2742
2743 case AckSent:
2744 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2745 {
2746 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2747 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2748 sess_local[s].ipcp.conf_sent++;
2749 sendipcp(s, t);
2750 change_state(s, ipcp, next_state);
2751 }
2752 else
2753 {
2754 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2755 STAT(session_timeout);
2756 }
2757
2758 s_actions++;
2759 }
2760
2761 if (session[s].die)
2762 continue;
2763 }
2764
2765 if (sess_local[s].ipv6cp.restart <= time_now)
2766 {
2767 int next_state = session[s].ppp.ipv6cp;
2768 switch (session[s].ppp.ipv6cp)
2769 {
2770 case RequestSent:
2771 case AckReceived:
2772 next_state = RequestSent;
2773
2774 case AckSent:
2775 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2776 {
2777 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2778 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2779 sess_local[s].ipv6cp.conf_sent++;
2780 sendipv6cp(s, t);
2781 change_state(s, ipv6cp, next_state);
2782 }
2783 else
2784 {
2785 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2786 change_state(s, ipv6cp, Stopped);
2787 }
2788
2789 s_actions++;
2790 }
2791 }
2792
2793 if (sess_local[s].ccp.restart <= time_now)
2794 {
2795 int next_state = session[s].ppp.ccp;
2796 switch (session[s].ppp.ccp)
2797 {
2798 case RequestSent:
2799 case AckReceived:
2800 next_state = RequestSent;
2801
2802 case AckSent:
2803 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2804 {
2805 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2806 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2807 sess_local[s].ccp.conf_sent++;
2808 sendccp(s, t);
2809 change_state(s, ccp, next_state);
2810 }
2811 else
2812 {
2813 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2814 change_state(s, ccp, Stopped);
2815 }
2816
2817 s_actions++;
2818 }
2819 }
2820
2821 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2822 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2823 {
2824 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2825 STAT(session_timeout);
2826 s_actions++;
2827 continue;
2828 }
2829
2830 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2831 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2832 {
2833 uint8_t b[MAXCONTROL] = {0};
2834
2835 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2836 if (!q) continue;
2837
2838 *q = EchoReq;
2839 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2840 *(uint16_t *)(q + 2) = htons(8); // Length
2841 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2842
2843 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2844 (int)(time_now - session[s].last_packet));
2845 tunnelsend(b, 24, session[s].tunnel); // send it
2846 s_actions++;
2847 }
2848
2849 // Check for actions requested from the CLI
2850 if ((a = cli_session_actions[s].action))
2851 {
2852 int send = 0;
2853
2854 cli_session_actions[s].action = 0;
2855 if (a & CLI_SESS_KILL)
2856 {
2857 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2858 sessionshutdown(s, "Requested by administrator.", 3, 0);
2859 a = 0; // dead, no need to check for other actions
2860 s_actions++;
2861 }
2862
2863 if (a & CLI_SESS_NOSNOOP)
2864 {
2865 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2866 session[s].snoop_ip = 0;
2867 session[s].snoop_port = 0;
2868 s_actions++;
2869 send++;
2870 }
2871 else if (a & CLI_SESS_SNOOP)
2872 {
2873 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2874 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2875 cli_session_actions[s].snoop_port);
2876
2877 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2878 session[s].snoop_port = cli_session_actions[s].snoop_port;
2879 s_actions++;
2880 send++;
2881 }
2882
2883 if (a & CLI_SESS_NOTHROTTLE)
2884 {
2885 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2886 throttle_session(s, 0, 0);
2887 s_actions++;
2888 send++;
2889 }
2890 else if (a & CLI_SESS_THROTTLE)
2891 {
2892 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2893 cli_session_actions[s].throttle_in,
2894 cli_session_actions[s].throttle_out);
2895
2896 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2897 s_actions++;
2898 send++;
2899 }
2900
2901 if (a & CLI_SESS_NOFILTER)
2902 {
2903 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2904 filter_session(s, 0, 0);
2905 s_actions++;
2906 send++;
2907 }
2908 else if (a & CLI_SESS_FILTER)
2909 {
2910 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2911 cli_session_actions[s].filter_in,
2912 cli_session_actions[s].filter_out);
2913
2914 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2915 s_actions++;
2916 send++;
2917 }
2918
2919 if (send)
2920 cluster_send_session(s);
2921 }
2922
2923 // RADIUS interim accounting
2924 if (config->radius_accounting && config->radius_interim > 0
2925 && session[s].ip && !session[s].walled_garden
2926 && !sess_local[s].radius // RADIUS already in progress
2927 && time_now - sess_local[s].last_interim >= config->radius_interim)
2928 {
2929 int rad = radiusnew(s);
2930 if (!rad)
2931 {
2932 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2933 STAT(radius_overflow);
2934 continue;
2935 }
2936
2937 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2938 session[s].user, session[s].unique_id);
2939
2940 radiussend(rad, RADIUSINTERIM);
2941 sess_local[s].last_interim = time_now;
2942 s_actions++;
2943 }
2944 }
2945
2946 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2947 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2948 }
2949
2950 //
2951 // Are we in the middle of a tunnel update, or radius
2952 // requests??
2953 //
2954 static int still_busy(void)
2955 {
2956 int i;
2957 static clockt last_talked = 0;
2958 static clockt start_busy_wait = 0;
2959
2960 if (!config->cluster_iam_master)
2961 {
2962 #ifdef BGP
2963 static time_t stopped_bgp = 0;
2964 if (bgp_configured)
2965 {
2966 if (!stopped_bgp)
2967 {
2968 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2969
2970 for (i = 0; i < BGP_NUM_PEERS; i++)
2971 if (bgp_peers[i].state == Established)
2972 bgp_stop(&bgp_peers[i]);
2973
2974 stopped_bgp = time_now;
2975
2976 // we don't want to become master
2977 cluster_send_ping(0);
2978
2979 return 1;
2980 }
2981
2982 if (time_now < (stopped_bgp + QUIT_DELAY))
2983 return 1;
2984 }
2985 #endif /* BGP */
2986
2987 return 0;
2988 }
2989
2990 if (main_quit == QUIT_SHUTDOWN)
2991 {
2992 static int dropped = 0;
2993 if (!dropped)
2994 {
2995 int i;
2996
2997 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
2998 for (i = 1; i < MAXTUNNEL; i++)
2999 if (tunnel[i].ip || tunnel[i].state)
3000 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3001
3002 dropped = 1;
3003 }
3004 }
3005
3006 if (start_busy_wait == 0)
3007 start_busy_wait = TIME;
3008
3009 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3010 {
3011 if (!tunnel[i].controlc)
3012 continue;
3013
3014 if (last_talked != TIME)
3015 {
3016 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3017 last_talked = TIME;
3018 }
3019 return 1;
3020 }
3021
3022 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3023 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3024 {
3025 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3026 return 0;
3027 }
3028
3029 for (i = 1; i < MAXRADIUS; i++)
3030 {
3031 if (radius[i].state == RADIUSNULL)
3032 continue;
3033 if (radius[i].state == RADIUSWAIT)
3034 continue;
3035
3036 if (last_talked != TIME)
3037 {
3038 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3039 last_talked = TIME;
3040 }
3041 return 1;
3042 }
3043
3044 return 0;
3045 }
3046
3047 #ifdef HAVE_EPOLL
3048 # include <sys/epoll.h>
3049 #else
3050 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3051 # include "fake_epoll.h"
3052 #endif
3053
3054 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3055 #define BASE_FDS 6
3056
3057 // additional polled fds
3058 #ifdef BGP
3059 # define EXTRA_FDS BGP_NUM_PEERS
3060 #else
3061 # define EXTRA_FDS 0
3062 #endif
3063
3064 // main loop - gets packets on tun or udp and processes them
3065 static void mainloop(void)
3066 {
3067 int i;
3068 uint8_t buf[65536];
3069 clockt next_cluster_ping = 0; // send initial ping immediately
3070 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3071 int maxevent = sizeof(events)/sizeof(*events);
3072
3073 if ((epollfd = epoll_create(maxevent)) < 0)
3074 {
3075 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3076 exit(1);
3077 }
3078
3079 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3080 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3081
3082 /* setup our fds to poll for input */
3083 {
3084 static struct event_data d[BASE_FDS];
3085 struct epoll_event e;
3086
3087 e.events = EPOLLIN;
3088 i = 0;
3089
3090 d[i].type = FD_TYPE_CLI;
3091 e.data.ptr = &d[i++];
3092 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3093
3094 d[i].type = FD_TYPE_CLUSTER;
3095 e.data.ptr = &d[i++];
3096 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3097
3098 d[i].type = FD_TYPE_TUN;
3099 e.data.ptr = &d[i++];
3100 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3101
3102 d[i].type = FD_TYPE_UDP;
3103 e.data.ptr = &d[i++];
3104 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3105
3106 d[i].type = FD_TYPE_CONTROL;
3107 e.data.ptr = &d[i++];
3108 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3109
3110 d[i].type = FD_TYPE_DAE;
3111 e.data.ptr = &d[i++];
3112 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3113 }
3114
3115 #ifdef BGP
3116 signal(SIGPIPE, SIG_IGN);
3117 bgp_setup(config->as_number);
3118 if (config->bind_address)
3119 bgp_add_route(config->bind_address, 0xffffffff);
3120
3121 for (i = 0; i < BGP_NUM_PEERS; i++)
3122 {
3123 if (config->neighbour[i].name[0])
3124 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3125 config->neighbour[i].as, config->neighbour[i].keepalive,
3126 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3127 }
3128 #endif /* BGP */
3129
3130 while (!main_quit || still_busy())
3131 {
3132 int more = 0;
3133 int n;
3134
3135 if (config->reload_config)
3136 {
3137 // Update the config state based on config settings
3138 update_config();
3139 }
3140
3141 #ifdef BGP
3142 bgp_set_poll();
3143 #endif /* BGP */
3144
3145 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3146 STAT(select_called);
3147
3148 TIME = now(NULL);
3149 if (n < 0)
3150 {
3151 if (errno == EINTR ||
3152 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3153 continue;
3154
3155 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3156 break; // exit
3157 }
3158
3159 if (n)
3160 {
3161 struct sockaddr_in addr;
3162 socklen_t alen;
3163 int c, s;
3164 int udp_ready = 0;
3165 int tun_ready = 0;
3166 int cluster_ready = 0;
3167 int udp_pkts = 0;
3168 int tun_pkts = 0;
3169 int cluster_pkts = 0;
3170 #ifdef BGP
3171 uint32_t bgp_events[BGP_NUM_PEERS];
3172 memset(bgp_events, 0, sizeof(bgp_events));
3173 #endif /* BGP */
3174
3175 for (c = n, i = 0; i < c; i++)
3176 {
3177 struct event_data *d = events[i].data.ptr;
3178 switch (d->type)
3179 {
3180 case FD_TYPE_CLI: // CLI connections
3181 {
3182 int cli;
3183
3184 alen = sizeof(addr);
3185 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3186 {
3187 cli_do(cli);
3188 close(cli);
3189 }
3190 else
3191 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3192
3193 n--;
3194 break;
3195 }
3196
3197 // these are handled below, with multiple interleaved reads
3198 case FD_TYPE_CLUSTER: cluster_ready++; break;
3199 case FD_TYPE_TUN: tun_ready++; break;
3200 case FD_TYPE_UDP: udp_ready++; break;
3201
3202 case FD_TYPE_CONTROL: // nsctl commands
3203 alen = sizeof(addr);
3204 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3205 n--;
3206 break;
3207
3208 case FD_TYPE_DAE: // DAE requests
3209 alen = sizeof(addr);
3210 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3211 n--;
3212 break;
3213
3214 case FD_TYPE_RADIUS: // RADIUS response
3215 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3216 if (s >= 0 && config->cluster_iam_master)
3217 processrad(buf, s, d->index);
3218
3219 n--;
3220 break;
3221
3222 #ifdef BGP
3223 case FD_TYPE_BGP:
3224 bgp_events[d->index] = events[i].events;
3225 n--;
3226 break;
3227 #endif /* BGP */
3228
3229 default:
3230 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3231 }
3232 }
3233
3234 #ifdef BGP
3235 bgp_process(bgp_events);
3236 #endif /* BGP */
3237
3238 for (c = 0; n && c < config->multi_read_count; c++)
3239 {
3240 // L2TP
3241 if (udp_ready)
3242 {
3243 alen = sizeof(addr);
3244 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3245 {
3246 processudp(buf, s, &addr);
3247 udp_pkts++;
3248 }
3249 else
3250 {
3251 udp_ready = 0;
3252 n--;
3253 }
3254 }
3255
3256 // incoming IP
3257 if (tun_ready)
3258 {
3259 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3260 {
3261 processtun(buf, s);
3262 tun_pkts++;
3263 }
3264 else
3265 {
3266 tun_ready = 0;
3267 n--;
3268 }
3269 }
3270
3271 // cluster
3272 if (cluster_ready)
3273 {
3274 alen = sizeof(addr);
3275 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3276 {
3277 processcluster(buf, s, addr.sin_addr.s_addr);
3278 cluster_pkts++;
3279 }
3280 else
3281 {
3282 cluster_ready = 0;
3283 n--;
3284 }
3285 }
3286 }
3287
3288 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3289 STAT(multi_read_used);
3290
3291 if (c >= config->multi_read_count)
3292 {
3293 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3294 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3295
3296 STAT(multi_read_exceeded);
3297 more++;
3298 }
3299 }
3300
3301 // Runs on every machine (master and slaves).
3302 if (next_cluster_ping <= TIME)
3303 {
3304 // Check to see which of the cluster is still alive..
3305
3306 cluster_send_ping(basetime); // Only does anything if we're a slave
3307 cluster_check_master(); // ditto.
3308
3309 cluster_heartbeat(); // Only does anything if we're a master.
3310 cluster_check_slaves(); // ditto.
3311
3312 master_update_counts(); // If we're a slave, send our byte counters to our master.
3313
3314 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3315 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3316 else
3317 next_cluster_ping = TIME + config->cluster_hb_interval;
3318 }
3319
3320 if (!config->cluster_iam_master)
3321 continue;
3322
3323 // Run token bucket filtering queue..
3324 // Only run it every 1/10th of a second.
3325 {
3326 static clockt last_run = 0;
3327 if (last_run != TIME)
3328 {
3329 last_run = TIME;
3330 tbf_run_timer();
3331 }
3332 }
3333
3334 // Handle timeouts, retries etc.
3335 {
3336 static double last_clean = 0;
3337 double this_clean;
3338 double diff;
3339
3340 TIME = now(&this_clean);
3341 diff = this_clean - last_clean;
3342
3343 // Run during idle time (after we've handled
3344 // all incoming packets) or every 1/10th sec
3345 if (!more || diff > 0.1)
3346 {
3347 regular_cleanups(diff);
3348 last_clean = this_clean;
3349 }
3350 }
3351
3352 if (*config->accounting_dir)
3353 {
3354 static clockt next_acct = 0;
3355 static clockt next_shut_acct = 0;
3356
3357 if (next_acct <= TIME)
3358 {
3359 // Dump accounting data
3360 next_acct = TIME + ACCT_TIME;
3361 next_shut_acct = TIME + ACCT_SHUT_TIME;
3362 dump_acct_info(1);
3363 }
3364 else if (next_shut_acct <= TIME)
3365 {
3366 // Dump accounting data for shutdown sessions
3367 next_shut_acct = TIME + ACCT_SHUT_TIME;
3368 if (shut_acct_n)
3369 dump_acct_info(0);
3370 }
3371 }
3372 }
3373
3374 // Are we the master and shutting down??
3375 if (config->cluster_iam_master)
3376 cluster_heartbeat(); // Flush any queued changes..
3377
3378 // Ok. Notify everyone we're shutting down. If we're
3379 // the master, this will force an election.
3380 cluster_send_ping(0);
3381
3382 //
3383 // Important!!! We MUST not process any packets past this point!
3384 LOG(1, 0, 0, "Shutdown complete\n");
3385 }
3386
3387 static void stripdomain(char *host)
3388 {
3389 char *p;
3390
3391 if ((p = strchr(host, '.')))
3392 {
3393 char *domain = 0;
3394 char _domain[1024];
3395
3396 // strip off domain
3397 FILE *resolv = fopen("/etc/resolv.conf", "r");
3398 if (resolv)
3399 {
3400 char buf[1024];
3401 char *b;
3402
3403 while (fgets(buf, sizeof(buf), resolv))
3404 {
3405 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3406 continue;
3407
3408 if (!isspace(buf[6]))
3409 continue;
3410
3411 b = buf + 7;
3412 while (isspace(*b)) b++;
3413
3414 if (*b)
3415 {
3416 char *d = b;
3417 while (*b && !isspace(*b)) b++;
3418 *b = 0;
3419 if (buf[0] == 'd') // domain is canonical
3420 {
3421 domain = d;
3422 break;
3423 }
3424
3425 // first search line
3426 if (!domain)
3427 {
3428 // hold, may be subsequent domain line
3429 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3430 domain = _domain;
3431 }
3432 }
3433 }
3434
3435 fclose(resolv);
3436 }
3437
3438 if (domain)
3439 {
3440 int hl = strlen(host);
3441 int dl = strlen(domain);
3442 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3443 host[hl -dl - 1] = 0;
3444 }
3445 else
3446 {
3447 *p = 0; // everything after first dot
3448 }
3449 }
3450 }
3451
3452 // Init data structures
3453 static void initdata(int optdebug, char *optconfig)
3454 {
3455 int i;
3456
3457 if (!(config = shared_malloc(sizeof(configt))))
3458 {
3459 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3460 exit(1);
3461 }
3462
3463 memset(config, 0, sizeof(configt));
3464 time(&config->start_time);
3465 strncpy(config->config_file, optconfig, strlen(optconfig));
3466 config->debug = optdebug;
3467 config->num_tbfs = MAXTBFS;
3468 config->rl_rate = 28; // 28kbps
3469 config->cluster_master_min_adv = 1;
3470 config->ppp_restart_time = 3;
3471 config->ppp_max_configure = 10;
3472 config->ppp_max_failure = 5;
3473 strcpy(config->random_device, RANDOMDEVICE);
3474
3475 log_stream = stderr;
3476
3477 #ifdef RINGBUFFER
3478 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3479 {
3480 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3481 exit(1);
3482 }
3483 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3484 #endif
3485
3486 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3487 {
3488 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3489 exit(1);
3490 }
3491 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3492 {
3493 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3494 exit(1);
3495 }
3496 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3497 {
3498 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3499 exit(1);
3500 }
3501
3502 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3503 {
3504 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3505 exit(1);
3506 }
3507
3508 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3509 {
3510 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3511 exit(1);
3512 }
3513
3514 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3515 {
3516 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3517 exit(1);
3518 }
3519
3520 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3521 {
3522 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3523 exit(1);
3524 }
3525 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3526
3527 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3528 {
3529 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3530 exit(1);
3531 }
3532 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3533
3534 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3535 {
3536 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3537 exit(1);
3538 }
3539 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3540
3541 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3542 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3543 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3544 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3545
3546 // Put all the sessions on the free list marked as undefined.
3547 for (i = 1; i < MAXSESSION; i++)
3548 {
3549 session[i].next = i + 1;
3550 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3551 }
3552 session[MAXSESSION - 1].next = 0;
3553 sessionfree = 1;
3554
3555 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3556 for (i = 1; i < MAXTUNNEL; i++)
3557 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3558
3559 if (!*hostname)
3560 {
3561 // Grab my hostname unless it's been specified
3562 gethostname(hostname, sizeof(hostname));
3563 stripdomain(hostname);
3564 }
3565
3566 _statistics->start_time = _statistics->last_reset = time(NULL);
3567
3568 #ifdef BGP
3569 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3570 {
3571 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3572 exit(1);
3573 }
3574 #endif /* BGP */
3575 }
3576
3577 static int assign_ip_address(sessionidt s)
3578 {
3579 uint32_t i;
3580 int best = -1;
3581 time_t best_time = time_now;
3582 char *u = session[s].user;
3583 char reuse = 0;
3584
3585
3586 CSTAT(assign_ip_address);
3587
3588 for (i = 1; i < ip_pool_size; i++)
3589 {
3590 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3591 continue;
3592
3593 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3594 {
3595 best = i;
3596 reuse = 1;
3597 break;
3598 }
3599
3600 if (ip_address_pool[i].last < best_time)
3601 {
3602 best = i;
3603 if (!(best_time = ip_address_pool[i].last))
3604 break; // never used, grab this one
3605 }
3606 }
3607
3608 if (best < 0)
3609 {
3610 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3611 return 0;
3612 }
3613
3614 session[s].ip = ip_address_pool[best].address;
3615 session[s].ip_pool_index = best;
3616 ip_address_pool[best].assigned = 1;
3617 ip_address_pool[best].last = time_now;
3618 ip_address_pool[best].session = s;
3619 if (session[s].walled_garden)
3620 /* Don't track addresses of users in walled garden (note: this
3621 means that their address isn't "sticky" even if they get
3622 un-gardened). */
3623 ip_address_pool[best].user[0] = 0;
3624 else
3625 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3626
3627 STAT(ip_allocated);
3628 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3629 reuse ? "Reusing" : "Allocating", best);
3630
3631 return 1;
3632 }
3633
3634 static void free_ip_address(sessionidt s)
3635 {
3636 int i = session[s].ip_pool_index;
3637
3638
3639 CSTAT(free_ip_address);
3640
3641 if (!session[s].ip)
3642 return; // what the?
3643
3644 if (i < 0) // Is this actually part of the ip pool?
3645 i = 0;
3646
3647 STAT(ip_freed);
3648 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3649 session[s].ip = 0;
3650 ip_address_pool[i].assigned = 0;
3651 ip_address_pool[i].session = 0;
3652 ip_address_pool[i].last = time_now;
3653 }
3654
3655 //
3656 // Fsck the address pool against the session table.
3657 // Normally only called when we become a master.
3658 //
3659 // This isn't perfect: We aren't keep tracking of which
3660 // users used to have an IP address.
3661 //
3662 void rebuild_address_pool(void)
3663 {
3664 int i;
3665
3666 //
3667 // Zero the IP pool allocation, and build
3668 // a map from IP address to pool index.
3669 for (i = 1; i < MAXIPPOOL; ++i)
3670 {
3671 ip_address_pool[i].assigned = 0;
3672 ip_address_pool[i].session = 0;
3673 if (!ip_address_pool[i].address)
3674 continue;
3675
3676 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3677 }
3678
3679 for (i = 0; i < MAXSESSION; ++i)
3680 {
3681 int ipid;
3682 if (!(session[i].opened && session[i].ip))
3683 continue;
3684
3685 ipid = - lookup_ipmap(htonl(session[i].ip));
3686
3687 if (session[i].ip_pool_index < 0)
3688 {
3689 // Not allocated out of the pool.
3690 if (ipid < 1) // Not found in the pool either? good.
3691 continue;
3692
3693 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3694 i, fmtaddr(session[i].ip, 0), ipid);
3695
3696 // Fall through and process it as part of the pool.
3697 }
3698
3699
3700 if (ipid > MAXIPPOOL || ipid < 0)
3701 {
3702 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3703 ipid = -1;
3704 session[i].ip_pool_index = ipid;
3705 continue;
3706 }
3707
3708 ip_address_pool[ipid].assigned = 1;
3709 ip_address_pool[ipid].session = i;
3710 ip_address_pool[ipid].last = time_now;
3711 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3712 session[i].ip_pool_index = ipid;
3713 cache_ipmap(session[i].ip, i); // Fix the ip map.
3714 }
3715 }
3716
3717 //
3718 // Fix the address pool to match a changed session.
3719 // (usually when the master sends us an update).
3720 static void fix_address_pool(int sid)
3721 {
3722 int ipid;
3723
3724 ipid = session[sid].ip_pool_index;
3725
3726 if (ipid > ip_pool_size)
3727 return; // Ignore it. rebuild_address_pool will fix it up.
3728
3729 if (ip_address_pool[ipid].address != session[sid].ip)
3730 return; // Just ignore it. rebuild_address_pool will take care of it.
3731
3732 ip_address_pool[ipid].assigned = 1;
3733 ip_address_pool[ipid].session = sid;
3734 ip_address_pool[ipid].last = time_now;
3735 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3736 }
3737
3738 //
3739 // Add a block of addresses to the IP pool to hand out.
3740 //
3741 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3742 {
3743 int i;
3744 if (mask == 0)
3745 mask = 0xffffffff; // Host route only.
3746
3747 addr &= mask;
3748
3749 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3750 return ;
3751
3752 for (i = addr ;(i & mask) == addr; ++i)
3753 {
3754 if ((i & 0xff) == 0 || (i&0xff) == 255)
3755 continue; // Skip 0 and broadcast addresses.
3756
3757 ip_address_pool[ip_pool_size].address = i;
3758 ip_address_pool[ip_pool_size].assigned = 0;
3759 ++ip_pool_size;
3760 if (ip_pool_size >= MAXIPPOOL)
3761 {
3762 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3763 return;
3764 }
3765 }
3766 }
3767
3768 // Initialize the IP address pool
3769 static void initippool()
3770 {
3771 FILE *f;
3772 char *p;
3773 char buf[4096];
3774 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3775
3776 if (!(f = fopen(IPPOOLFILE, "r")))
3777 {
3778 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3779 exit(1);
3780 }
3781
3782 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3783 {
3784 char *pool = buf;
3785 buf[4095] = 0; // Force it to be zero terminated/
3786
3787 if (*buf == '#' || *buf == '\n')
3788 continue; // Skip comments / blank lines
3789 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3790 if ((p = (char *)strchr(buf, ':')))
3791 {
3792 in_addr_t src;
3793 *p = '\0';
3794 src = inet_addr(buf);
3795 if (src == INADDR_NONE)
3796 {
3797 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3798 exit(1);
3799 }
3800 // This entry is for a specific IP only
3801 if (src != config->bind_address)
3802 continue;
3803 *p = ':';
3804 pool = p+1;
3805 }
3806 if ((p = (char *)strchr(pool, '/')))
3807 {
3808 // It's a range
3809 int numbits = 0;
3810 in_addr_t start = 0, mask = 0;
3811
3812 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3813 *p++ = 0;
3814 if (!*p || !(numbits = atoi(p)))
3815 {
3816 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3817 continue;
3818 }
3819 start = ntohl(inet_addr(pool));
3820 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3821
3822 // Add a static route for this pool
3823 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3824 fmtaddr(htonl(start), 0), 32 + mask);
3825
3826 routeset(0, start, mask, 0, 1);
3827
3828 add_to_ip_pool(start, mask);
3829 }
3830 else
3831 {
3832 // It's a single ip address
3833 add_to_ip_pool(inet_addr(pool), 0);
3834 }
3835 }
3836 fclose(f);
3837 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3838 }
3839
3840 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3841 {
3842 struct sockaddr_in snoop_addr = {0};
3843 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3844 return;
3845
3846 snoop_addr.sin_family = AF_INET;
3847 snoop_addr.sin_addr.s_addr = destination;
3848 snoop_addr.sin_port = ntohs(port);
3849
3850 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3851 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3852 htons(snoop_addr.sin_port));
3853
3854 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3855 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3856
3857 STAT(packets_snooped);
3858 }
3859
3860 static int dump_session(FILE **f, sessiont *s)
3861 {
3862 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3863 return 1;
3864
3865 if (!*f)
3866 {
3867 char filename[1024];
3868 char timestr[64];
3869 time_t now = time(NULL);
3870
3871 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3872 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3873
3874 if (!(*f = fopen(filename, "w")))
3875 {
3876 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3877 return 0;
3878 }
3879
3880 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3881 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3882 "# host: %s\n"
3883 "# endpoint: %s\n"
3884 "# time: %ld\n"
3885 "# uptime: %ld\n"
3886 "# format: username ip qos uptxoctets downrxoctets\n",
3887 hostname,
3888 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3889 now,
3890 now - basetime);
3891 }
3892
3893 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3894 fprintf(*f, "%s %s %d %u %u\n",
3895 s->user, // username
3896 fmtaddr(htonl(s->ip), 0), // ip
3897 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3898 (uint32_t) s->cin_delta, // uptxoctets
3899 (uint32_t) s->cout_delta); // downrxoctets
3900
3901 s->cin_delta = s->cout_delta = 0;
3902
3903 return 1;
3904 }
3905
3906 static void dump_acct_info(int all)
3907 {
3908 int i;
3909 FILE *f = NULL;
3910
3911
3912 CSTAT(dump_acct_info);
3913
3914 if (shut_acct_n)
3915 {
3916 for (i = 0; i < shut_acct_n; i++)
3917 dump_session(&f, &shut_acct[i]);
3918
3919 shut_acct_n = 0;
3920 }
3921
3922 if (all)
3923 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3924 dump_session(&f, &session[i]);
3925
3926 if (f)
3927 fclose(f);
3928 }
3929
3930 // Main program
3931 int main(int argc, char *argv[])
3932 {
3933 int i;
3934 int optdebug = 0;
3935 char *optconfig = CONFIGFILE;
3936
3937 time(&basetime); // start clock
3938
3939 // scan args
3940 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3941 {
3942 switch (i)
3943 {
3944 case 'd':
3945 if (fork()) exit(0);
3946 setsid();
3947 freopen("/dev/null", "r", stdin);
3948 freopen("/dev/null", "w", stdout);
3949 freopen("/dev/null", "w", stderr);
3950 break;
3951 case 'v':
3952 optdebug++;
3953 break;
3954 case 'c':
3955 optconfig = optarg;
3956 break;
3957 case 'h':
3958 snprintf(hostname, sizeof(hostname), "%s", optarg);
3959 break;
3960 default:
3961 printf("Args are:\n"
3962 "\t-d\t\tDetach from terminal\n"
3963 "\t-c <file>\tConfig file\n"
3964 "\t-h <hostname>\tForce hostname\n"
3965 "\t-v\t\tDebug\n");
3966
3967 return (0);
3968 break;
3969 }
3970 }
3971
3972 // Start the timer routine off
3973 time(&time_now);
3974 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3975 signal(SIGALRM, sigalrm_handler);
3976 siginterrupt(SIGALRM, 0);
3977
3978 initplugins();
3979 initdata(optdebug, optconfig);
3980
3981 init_cli(hostname);
3982 read_config_file();
3983 init_tbf(config->num_tbfs);
3984
3985 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3986 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3987 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3988 {
3989 struct rlimit rlim;
3990 rlim.rlim_cur = RLIM_INFINITY;
3991 rlim.rlim_max = RLIM_INFINITY;
3992 // Remove the maximum core size
3993 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3994 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3995
3996 // Make core dumps go to /tmp
3997 chdir("/tmp");
3998 }
3999
4000 if (config->scheduler_fifo)
4001 {
4002 int ret;
4003 struct sched_param params = {0};
4004 params.sched_priority = 1;
4005
4006 if (get_nprocs() < 2)
4007 {
4008 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4009 config->scheduler_fifo = 0;
4010 }
4011 else
4012 {
4013 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4014 {
4015 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4016 }
4017 else
4018 {
4019 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4020 config->scheduler_fifo = 0;
4021 }
4022 }
4023 }
4024
4025 /* Set up the cluster communications port. */
4026 if (cluster_init() < 0)
4027 exit(1);
4028
4029 inittun();
4030 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4031
4032 initudp();
4033 initrad();
4034 initippool();
4035
4036 // seed prng
4037 {
4038 unsigned seed = time_now ^ getpid();
4039 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4040 srand(seed);
4041 }
4042
4043 signal(SIGHUP, sighup_handler);
4044 signal(SIGCHLD, sigchild_handler);
4045 signal(SIGTERM, shutdown_handler);
4046 signal(SIGINT, shutdown_handler);
4047 signal(SIGQUIT, shutdown_handler);
4048
4049 // Prevent us from getting paged out
4050 if (config->lock_pages)
4051 {
4052 if (!mlockall(MCL_CURRENT))
4053 LOG(1, 0, 0, "Locking pages into memory\n");
4054 else
4055 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4056 }
4057
4058 alarm(1);
4059
4060 // Drop privileges here
4061 if (config->target_uid > 0 && geteuid() == 0)
4062 setuid(config->target_uid);
4063
4064 mainloop();
4065
4066 /* remove plugins (so cleanup code gets run) */
4067 plugins_done();
4068
4069 // Remove the PID file if we wrote it
4070 if (config->wrote_pid && *config->pid_file == '/')
4071 unlink(config->pid_file);
4072
4073 /* kill CLI children */
4074 signal(SIGTERM, SIG_IGN);
4075 kill(0, SIGTERM);
4076 return 0;
4077 }
4078
4079 static void sighup_handler(int sig)
4080 {
4081 if (log_stream)
4082 {
4083 if (log_stream != stderr)
4084 fclose(log_stream);
4085
4086 log_stream = NULL;
4087 }
4088
4089 read_config_file();
4090 }
4091
4092 static void sigalrm_handler(int sig)
4093 {
4094 // Log current traffic stats
4095
4096 snprintf(config->bandwidth, sizeof(config->bandwidth),
4097 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4098 (udp_rx / 1024.0 / 1024.0 * 8),
4099 (eth_tx / 1024.0 / 1024.0 * 8),
4100 (eth_rx / 1024.0 / 1024.0 * 8),
4101 (udp_tx / 1024.0 / 1024.0 * 8),
4102 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4103 udp_rx_pkt, eth_rx_pkt);
4104
4105 udp_tx = udp_rx = 0;
4106 udp_rx_pkt = eth_rx_pkt = 0;
4107 eth_tx = eth_rx = 0;
4108
4109 if (config->dump_speed)
4110 printf("%s\n", config->bandwidth);
4111
4112 // Update the internal time counter
4113 time(&time_now);
4114 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4115 alarm(1);
4116
4117 {
4118 // Run timer hooks
4119 struct param_timer p = { time_now };
4120 run_plugins(PLUGIN_TIMER, &p);
4121 }
4122
4123 }
4124
4125 static void shutdown_handler(int sig)
4126 {
4127 LOG(1, 0, 0, "Shutting down\n");
4128 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4129 }
4130
4131 static void sigchild_handler(int sig)
4132 {
4133 while (waitpid(-1, NULL, WNOHANG) > 0)
4134 ;
4135 }
4136
4137 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4138 {
4139 MD5_CTX ctx;
4140 *challenge_response = NULL;
4141
4142 if (!*config->l2tpsecret)
4143 {
4144 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4145 return;
4146 }
4147
4148 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4149
4150 *challenge_response = calloc(17, 1);
4151
4152 MD5_Init(&ctx);
4153 MD5_Update(&ctx, &id, 1);
4154 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4155 MD5_Update(&ctx, challenge, challenge_length);
4156 MD5_Final(*challenge_response, &ctx);
4157
4158 return;
4159 }
4160
4161 static int facility_value(char *name)
4162 {
4163 int i;
4164 for (i = 0; facilitynames[i].c_name; i++)
4165 {
4166 if (strcmp(facilitynames[i].c_name, name) == 0)
4167 return facilitynames[i].c_val;
4168 }
4169 return 0;
4170 }
4171
4172 static void update_config()
4173 {
4174 int i;
4175 char *p;
4176 static int timeout = 0;
4177 static int interval = 0;
4178
4179 // Update logging
4180 closelog();
4181 syslog_log = 0;
4182 if (log_stream)
4183 {
4184 if (log_stream != stderr)
4185 fclose(log_stream);
4186
4187 log_stream = NULL;
4188 }
4189
4190 if (*config->log_filename)
4191 {
4192 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4193 {
4194 char *p = config->log_filename + 7;
4195 if (*p)
4196 {
4197 openlog("l2tpns", LOG_PID, facility_value(p));
4198 syslog_log = 1;
4199 }
4200 }
4201 else if (strchr(config->log_filename, '/') == config->log_filename)
4202 {
4203 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4204 {
4205 fseek(log_stream, 0, SEEK_END);
4206 setbuf(log_stream, NULL);
4207 }
4208 else
4209 {
4210 log_stream = stderr;
4211 setbuf(log_stream, NULL);
4212 }
4213 }
4214 }
4215 else
4216 {
4217 log_stream = stderr;
4218 setbuf(log_stream, NULL);
4219 }
4220
4221 // Update radius
4222 config->numradiusservers = 0;
4223 for (i = 0; i < MAXRADSERVER; i++)
4224 if (config->radiusserver[i])
4225 {
4226 config->numradiusservers++;
4227 // Set radius port: if not set, take the port from the
4228 // first radius server. For the first radius server,
4229 // take the #defined default value from l2tpns.h
4230
4231 // test twice, In case someone works with
4232 // a secondary radius server without defining
4233 // a primary one, this will work even then.
4234 if (i > 0 && !config->radiusport[i])
4235 config->radiusport[i] = config->radiusport[i-1];
4236 if (!config->radiusport[i])
4237 config->radiusport[i] = RADPORT;
4238 }
4239
4240 if (!config->numradiusservers)
4241 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4242
4243 // parse radius_authtypes_s
4244 config->radius_authtypes = config->radius_authprefer = 0;
4245 p = config->radius_authtypes_s;
4246 while (p && *p)
4247 {
4248 char *s = strpbrk(p, " \t,");
4249 int type = 0;
4250
4251 if (s)
4252 {
4253 *s++ = 0;
4254 while (*s == ' ' || *s == '\t')
4255 s++;
4256
4257 if (!*s)
4258 s = 0;
4259 }
4260
4261 if (!strncasecmp("chap", p, strlen(p)))
4262 type = AUTHCHAP;
4263 else if (!strncasecmp("pap", p, strlen(p)))
4264 type = AUTHPAP;
4265 else
4266 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4267
4268 config->radius_authtypes |= type;
4269 if (!config->radius_authprefer)
4270 config->radius_authprefer = type;
4271
4272 p = s;
4273 }
4274
4275 if (!config->radius_authtypes)
4276 {
4277 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4278 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4279 }
4280
4281 // normalise radius_authtypes_s
4282 if (config->radius_authprefer == AUTHPAP)
4283 {
4284 strcpy(config->radius_authtypes_s, "pap");
4285 if (config->radius_authtypes & AUTHCHAP)
4286 strcat(config->radius_authtypes_s, ", chap");
4287 }
4288 else
4289 {
4290 strcpy(config->radius_authtypes_s, "chap");
4291 if (config->radius_authtypes & AUTHPAP)
4292 strcat(config->radius_authtypes_s, ", pap");
4293 }
4294
4295 if (!config->radius_dae_port)
4296 config->radius_dae_port = DAEPORT;
4297
4298 // re-initialise the random number source
4299 initrandom(config->random_device);
4300
4301 // Update plugins
4302 for (i = 0; i < MAXPLUGINS; i++)
4303 {
4304 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4305 continue;
4306
4307 if (*config->plugins[i])
4308 {
4309 // Plugin added
4310 add_plugin(config->plugins[i]);
4311 }
4312 else if (*config->old_plugins[i])
4313 {
4314 // Plugin removed
4315 remove_plugin(config->old_plugins[i]);
4316 }
4317 }
4318
4319 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4320 if (!config->multi_read_count) config->multi_read_count = 10;
4321 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4322 if (!*config->cluster_interface)
4323 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4324
4325 if (!config->cluster_hb_interval)
4326 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4327
4328 if (!config->cluster_hb_timeout)
4329 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4330
4331 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4332 {
4333 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4334 // late, ensure we're sufficiently larger than that
4335 int t = 4 * config->cluster_hb_interval + 11;
4336
4337 if (config->cluster_hb_timeout < t)
4338 {
4339 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4340 config->cluster_hb_timeout = t;
4341 }
4342
4343 // Push timing changes to the slaves immediately if we're the master
4344 if (config->cluster_iam_master)
4345 cluster_heartbeat();
4346
4347 interval = config->cluster_hb_interval;
4348 timeout = config->cluster_hb_timeout;
4349 }
4350
4351 // Write PID file
4352 if (*config->pid_file == '/' && !config->wrote_pid)
4353 {
4354 FILE *f;
4355 if ((f = fopen(config->pid_file, "w")))
4356 {
4357 fprintf(f, "%d\n", getpid());
4358 fclose(f);
4359 config->wrote_pid = 1;
4360 }
4361 else
4362 {
4363 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4364 }
4365 }
4366
4367 config->reload_config = 0;
4368 }
4369
4370 static void read_config_file()
4371 {
4372 FILE *f;
4373
4374 if (!config->config_file) return;
4375 if (!(f = fopen(config->config_file, "r")))
4376 {
4377 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4378 return;
4379 }
4380
4381 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4382 cli_do_file(f);
4383 LOG(3, 0, 0, "Done reading config file\n");
4384 fclose(f);
4385 update_config();
4386 }
4387
4388 int sessionsetup(sessionidt s, tunnelidt t)
4389 {
4390 // A session now exists, set it up
4391 in_addr_t ip;
4392 char *user;
4393 sessionidt i;
4394 int r;
4395
4396 CSTAT(sessionsetup);
4397
4398 LOG(3, s, t, "Doing session setup for session\n");
4399
4400 if (!session[s].ip)
4401 {
4402 assign_ip_address(s);
4403 if (!session[s].ip)
4404 {
4405 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4406 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4407 return 0;
4408 }
4409 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4410 fmtaddr(htonl(session[s].ip), 0));
4411 }
4412
4413
4414 // Make sure this is right
4415 session[s].tunnel = t;
4416
4417 // zap old sessions with same IP and/or username
4418 // Don't kill gardened sessions - doing so leads to a DoS
4419 // from someone who doesn't need to know the password
4420 {
4421 ip = session[s].ip;
4422 user = session[s].user;
4423 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4424 {
4425 if (i == s) continue;
4426 if (!session[s].opened) continue;
4427 if (ip == session[i].ip)
4428 {
4429 sessionkill(i, "Duplicate IP address");
4430 continue;
4431 }
4432
4433 if (config->allow_duplicate_users) continue;
4434 if (session[s].walled_garden || session[i].walled_garden) continue;
4435 if (!strcasecmp(user, session[i].user))
4436 sessionkill(i, "Duplicate session for users");
4437 }
4438 }
4439
4440 {
4441 int routed = 0;
4442
4443 // Add the route for this session.
4444 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4445 {
4446 if ((session[s].ip & session[s].route[r].mask) ==
4447 (session[s].route[r].ip & session[s].route[r].mask))
4448 routed++;
4449
4450 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4451 }
4452
4453 // Static IPs need to be routed if not already
4454 // convered by a Framed-Route. Anything else is part
4455 // of the IP address pool and is already routed, it
4456 // just needs to be added to the IP cache.
4457 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4458 if (session[s].ip_pool_index == -1) // static ip
4459 {
4460 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4461 }
4462 else
4463 cache_ipmap(session[s].ip, s);
4464 }
4465
4466 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4467 lcp_open(s, t); // transition to Network phase and send initial IPCP
4468
4469 // Run the plugin's against this new session.
4470 {
4471 struct param_new_session data = { &tunnel[t], &session[s] };
4472 run_plugins(PLUGIN_NEW_SESSION, &data);
4473 }
4474
4475 // Allocate TBFs if throttled
4476 if (session[s].throttle_in || session[s].throttle_out)
4477 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4478
4479 session[s].last_packet = time_now;
4480
4481 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4482 fmtaddr(htonl(session[s].ip), 0),
4483 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4484
4485 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4486
4487 return 1; // RADIUS OK and IP allocated, done...
4488 }
4489
4490 //
4491 // This session just got dropped on us by the master or something.
4492 // Make sure our tables up up to date...
4493 //
4494 int load_session(sessionidt s, sessiont *new)
4495 {
4496 int i;
4497 int newip = 0;
4498
4499 // Sanity checks.
4500 if (new->ip_pool_index >= MAXIPPOOL ||
4501 new->tunnel >= MAXTUNNEL)
4502 {
4503 LOG(0, s, 0, "Strange session update received!\n");
4504 // FIXME! What to do here?
4505 return 0;
4506 }
4507
4508 //
4509 // Ok. All sanity checks passed. Now we're committed to
4510 // loading the new session.
4511 //
4512
4513 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4514
4515 // See if routes/ip cache need updating
4516 if (new->ip != session[s].ip)
4517 newip++;
4518
4519 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4520 if (new->route[i].ip != session[s].route[i].ip ||
4521 new->route[i].mask != session[s].route[i].mask)
4522 newip++;
4523
4524 // needs update
4525 if (newip)
4526 {
4527 int routed = 0;
4528
4529 // remove old routes...
4530 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4531 {
4532 if ((session[s].ip & session[s].route[i].mask) ==
4533 (session[s].route[i].ip & session[s].route[i].mask))
4534 routed++;
4535
4536 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4537 }
4538
4539 // ...ip
4540 if (session[s].ip)
4541 {
4542 if (session[s].ip_pool_index == -1) // static IP
4543 {
4544 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4545 }
4546 else // It's part of the IP pool, remove it manually.
4547 uncache_ipmap(session[s].ip);
4548 }
4549
4550 routed = 0;
4551
4552 // add new routes...
4553 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4554 {
4555 if ((new->ip & new->route[i].mask) ==
4556 (new->route[i].ip & new->route[i].mask))
4557 routed++;
4558
4559 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4560 }
4561
4562 // ...ip
4563 if (new->ip)
4564 {
4565 // If there's a new one, add it.
4566 if (new->ip_pool_index == -1)
4567 {
4568 if (!routed) routeset(s, new->ip, 0, 0, 1);
4569 }
4570 else
4571 cache_ipmap(new->ip, s);
4572 }
4573 }
4574
4575 // check v6 routing
4576 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4577 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4578
4579 // check filters
4580 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4581 {
4582 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4583 new->filter_in = 0;
4584 }
4585
4586 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4587 {
4588 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4589 new->filter_out = 0;
4590 }
4591
4592 if (new->filter_in != session[s].filter_in)
4593 {
4594 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4595 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4596 }
4597
4598 if (new->filter_out != session[s].filter_out)
4599 {
4600 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4601 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4602 }
4603
4604 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4605 // for walking the sessions to forward byte counts to the master.
4606 config->cluster_highest_sessionid = s;
4607
4608 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4609
4610 // Do fixups into address pool.
4611 if (new->ip_pool_index != -1)
4612 fix_address_pool(s);
4613
4614 return 1;
4615 }
4616
4617 static void initplugins()
4618 {
4619 int i;
4620
4621 loaded_plugins = ll_init();
4622 // Initialize the plugins to nothing
4623 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4624 plugins[i] = ll_init();
4625 }
4626
4627 static void *open_plugin(char *plugin_name, int load)
4628 {
4629 char path[256] = "";
4630
4631 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4632 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4633 return dlopen(path, RTLD_NOW);
4634 }
4635
4636 // plugin callback to get a config value
4637 static void *getconfig(char *key, enum config_typet type)
4638 {
4639 int i;
4640
4641 for (i = 0; config_values[i].key; i++)
4642 {
4643 if (!strcmp(config_values[i].key, key))
4644 {
4645 if (config_values[i].type == type)
4646 return ((void *) config) + config_values[i].offset;
4647
4648 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4649 key, type, config_values[i].type);
4650
4651 return 0;
4652 }
4653 }
4654
4655 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4656 return 0;
4657 }
4658
4659 static int add_plugin(char *plugin_name)
4660 {
4661 static struct pluginfuncs funcs = {
4662 _log,
4663 _log_hex,
4664 fmtaddr,
4665 sessionbyuser,
4666 sessiontbysessionidt,
4667 sessionidtbysessiont,
4668 radiusnew,
4669 radiussend,
4670 getconfig,
4671 sessionshutdown,
4672 sessionkill,
4673 throttle_session,
4674 cluster_send_session,
4675 };
4676
4677 void *p = open_plugin(plugin_name, 1);
4678 int (*initfunc)(struct pluginfuncs *);
4679 int i;
4680
4681 if (!p)
4682 {
4683 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4684 return -1;
4685 }
4686
4687 if (ll_contains(loaded_plugins, p))
4688 {
4689 dlclose(p);
4690 return 0; // already loaded
4691 }
4692
4693 {
4694 int *v = dlsym(p, "plugin_api_version");
4695 if (!v || *v != PLUGIN_API_VERSION)
4696 {
4697 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4698 dlclose(p);
4699 return -1;
4700 }
4701 }
4702
4703 if ((initfunc = dlsym(p, "plugin_init")))
4704 {
4705 if (!initfunc(&funcs))
4706 {
4707 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4708 dlclose(p);
4709 return -1;
4710 }
4711 }
4712
4713 ll_push(loaded_plugins, p);
4714
4715 for (i = 0; i < max_plugin_functions; i++)
4716 {
4717 void *x;
4718 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4719 {
4720 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4721 ll_push(plugins[i], x);
4722 }
4723 }
4724
4725 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4726 return 1;
4727 }
4728
4729 static void run_plugin_done(void *plugin)
4730 {
4731 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4732
4733 if (donefunc)
4734 donefunc();
4735 }
4736
4737 static int remove_plugin(char *plugin_name)
4738 {
4739 void *p = open_plugin(plugin_name, 0);
4740 int loaded = 0;
4741
4742 if (!p)
4743 return -1;
4744
4745 if (ll_contains(loaded_plugins, p))
4746 {
4747 int i;
4748 for (i = 0; i < max_plugin_functions; i++)
4749 {
4750 void *x;
4751 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4752 ll_delete(plugins[i], x);
4753 }
4754
4755 ll_delete(loaded_plugins, p);
4756 run_plugin_done(p);
4757 loaded = 1;
4758 }
4759
4760 dlclose(p);
4761 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4762 return loaded;
4763 }
4764
4765 int run_plugins(int plugin_type, void *data)
4766 {
4767 int (*func)(void *data);
4768
4769 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4770 return PLUGIN_RET_ERROR;
4771
4772 ll_reset(plugins[plugin_type]);
4773 while ((func = ll_next(plugins[plugin_type])))
4774 {
4775 int r = func(data);
4776
4777 if (r != PLUGIN_RET_OK)
4778 return r; // stop here
4779 }
4780
4781 return PLUGIN_RET_OK;
4782 }
4783
4784 static void plugins_done()
4785 {
4786 void *p;
4787
4788 ll_reset(loaded_plugins);
4789 while ((p = ll_next(loaded_plugins)))
4790 run_plugin_done(p);
4791 }
4792
4793 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4794 {
4795 struct nsctl request;
4796 struct nsctl response;
4797 int type = unpack_control(&request, buf, len);
4798 int r;
4799 void *p;
4800
4801 if (log_stream && config->debug >= 4)
4802 {
4803 if (type < 0)
4804 {
4805 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4806 fmtaddr(addr->sin_addr.s_addr, 0), type);
4807 }
4808 else
4809 {
4810 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4811 dump_control(&request, log_stream);
4812 }
4813 }
4814
4815 switch (type)
4816 {
4817 case NSCTL_REQ_LOAD:
4818 if (request.argc != 1)
4819 {
4820 response.type = NSCTL_RES_ERR;
4821 response.argc = 1;
4822 response.argv[0] = "name of plugin required";
4823 }
4824 else if ((r = add_plugin(request.argv[0])) < 1)
4825 {
4826 response.type = NSCTL_RES_ERR;
4827 response.argc = 1;
4828 response.argv[0] = !r
4829 ? "plugin already loaded"
4830 : "error loading plugin";
4831 }
4832 else
4833 {
4834 response.type = NSCTL_RES_OK;
4835 response.argc = 0;
4836 }
4837
4838 break;
4839
4840 case NSCTL_REQ_UNLOAD:
4841 if (request.argc != 1)
4842 {
4843 response.type = NSCTL_RES_ERR;
4844 response.argc = 1;
4845 response.argv[0] = "name of plugin required";
4846 }
4847 else if ((r = remove_plugin(request.argv[0])) < 1)
4848 {
4849 response.type = NSCTL_RES_ERR;
4850 response.argc = 1;
4851 response.argv[0] = !r
4852 ? "plugin not loaded"
4853 : "plugin not found";
4854 }
4855 else
4856 {
4857 response.type = NSCTL_RES_OK;
4858 response.argc = 0;
4859 }
4860
4861 break;
4862
4863 case NSCTL_REQ_HELP:
4864 response.type = NSCTL_RES_OK;
4865 response.argc = 0;
4866
4867 ll_reset(loaded_plugins);
4868 while ((p = ll_next(loaded_plugins)))
4869 {
4870 char **help = dlsym(p, "plugin_control_help");
4871 while (response.argc < 0xff && help && *help)
4872 response.argv[response.argc++] = *help++;
4873 }
4874
4875 break;
4876
4877 case NSCTL_REQ_CONTROL:
4878 {
4879 struct param_control param = {
4880 config->cluster_iam_master,
4881 request.argc,
4882 request.argv,
4883 0,
4884 NULL,
4885 };
4886
4887 int r = run_plugins(PLUGIN_CONTROL, &param);
4888
4889 if (r == PLUGIN_RET_ERROR)
4890 {
4891 response.type = NSCTL_RES_ERR;
4892 response.argc = 1;
4893 response.argv[0] = param.additional
4894 ? param.additional
4895 : "error returned by plugin";
4896 }
4897 else if (r == PLUGIN_RET_NOTMASTER)
4898 {
4899 static char msg[] = "must be run on master: 000.000.000.000";
4900
4901 response.type = NSCTL_RES_ERR;
4902 response.argc = 1;
4903 if (config->cluster_master_address)
4904 {
4905 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4906 response.argv[0] = msg;
4907 }
4908 else
4909 {
4910 response.argv[0] = "must be run on master: none elected";
4911 }
4912 }
4913 else if (!(param.response & NSCTL_RESPONSE))
4914 {
4915 response.type = NSCTL_RES_ERR;
4916 response.argc = 1;
4917 response.argv[0] = param.response
4918 ? "unrecognised response value from plugin"
4919 : "unhandled action";
4920 }
4921 else
4922 {
4923 response.type = param.response;
4924 response.argc = 0;
4925 if (param.additional)
4926 {
4927 response.argc = 1;
4928 response.argv[0] = param.additional;
4929 }
4930 }
4931 }
4932
4933 break;
4934
4935 default:
4936 response.type = NSCTL_RES_ERR;
4937 response.argc = 1;
4938 response.argv[0] = "error unpacking control packet";
4939 }
4940
4941 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4942 if (!buf)
4943 {
4944 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4945 return;
4946 }
4947
4948 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4949 if (r > 0)
4950 {
4951 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4952 if (log_stream && config->debug >= 4)
4953 {
4954 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4955 dump_control(&response, log_stream);
4956 }
4957 }
4958 else
4959 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4960 fmtaddr(addr->sin_addr.s_addr, 0), r);
4961
4962 free(buf);
4963 }
4964
4965 static tunnelidt new_tunnel()
4966 {
4967 tunnelidt i;
4968 for (i = 1; i < MAXTUNNEL; i++)
4969 {
4970 if (tunnel[i].state == TUNNELFREE)
4971 {
4972 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4973 if (i > config->cluster_highest_tunnelid)
4974 config->cluster_highest_tunnelid = i;
4975 return i;
4976 }
4977 }
4978 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4979 return 0;
4980 }
4981
4982 //
4983 // We're becoming the master. Do any required setup..
4984 //
4985 // This is principally telling all the plugins that we're
4986 // now a master, and telling them about all the sessions
4987 // that are active too..
4988 //
4989 void become_master(void)
4990 {
4991 int s, i;
4992 static struct event_data d[RADIUS_FDS];
4993 struct epoll_event e;
4994
4995 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4996
4997 // running a bunch of iptables commands is slow and can cause
4998 // the master to drop tunnels on takeover--kludge around the
4999 // problem by forking for the moment (note: race)
5000 if (!fork_and_close())
5001 {
5002 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5003 {
5004 if (!session[s].opened) // Not an in-use session.
5005 continue;
5006
5007 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5008 }
5009 exit(0);
5010 }
5011
5012 // add radius fds
5013 e.events = EPOLLIN;
5014 for (i = 0; i < RADIUS_FDS; i++)
5015 {
5016 d[i].type = FD_TYPE_RADIUS;
5017 d[i].index = i;
5018 e.data.ptr = &d[i];
5019
5020 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5021 }
5022 }
5023
5024 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5025 {
5026 int s, i;
5027 int count = 0;
5028 int buckets[64];
5029
5030 if (CLI_HELP_REQUESTED)
5031 return CLI_HELP_NO_ARGS;
5032
5033 time(&time_now);
5034 for (i = 0; i < 64;++i) buckets[i] = 0;
5035
5036 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5037 {
5038 int idle;
5039 if (!session[s].opened)
5040 continue;
5041
5042 idle = time_now - session[s].last_packet;
5043 idle /= 5 ; // In multiples of 5 seconds.
5044 if (idle < 0)
5045 idle = 0;
5046 if (idle > 63)
5047 idle = 63;
5048
5049 ++count;
5050 ++buckets[idle];
5051 }
5052
5053 for (i = 0; i < 63; ++i)
5054 {
5055 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5056 }
5057 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5058 cli_print(cli, "%d total sessions open.", count);
5059 return CLI_OK;
5060 }
5061
5062 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5063 {
5064 int s, i;
5065 int count = 0;
5066 int buckets[64];
5067
5068 if (CLI_HELP_REQUESTED)
5069 return CLI_HELP_NO_ARGS;
5070
5071 time(&time_now);
5072 for (i = 0; i < 64;++i) buckets[i] = 0;
5073
5074 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5075 {
5076 int open = 0, d;
5077 if (!session[s].opened)
5078 continue;
5079
5080 d = time_now - session[s].opened;
5081 if (d < 0)
5082 d = 0;
5083 while (d > 1 && open < 32)
5084 {
5085 ++open;
5086 d >>= 1; // half.
5087 }
5088 ++count;
5089 ++buckets[open];
5090 }
5091
5092 s = 1;
5093 for (i = 0; i < 30; ++i)
5094 {
5095 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5096 s <<= 1;
5097 }
5098 cli_print(cli, "%d total sessions open.", count);
5099 return CLI_OK;
5100 }
5101
5102 /* Unhide an avp.
5103 *
5104 * This unencodes the AVP using the L2TP secret and the previously
5105 * stored random vector. It overwrites the hidden data with the
5106 * unhidden AVP subformat.
5107 */
5108 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5109 {
5110 MD5_CTX ctx;
5111 uint8_t digest[16];
5112 uint8_t *last;
5113 size_t d = 0;
5114 uint16_t m = htons(type);
5115
5116 // Compute initial pad
5117 MD5_Init(&ctx);
5118 MD5_Update(&ctx, (unsigned char *) &m, 2);
5119 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5120 MD5_Update(&ctx, vector, vec_len);
5121 MD5_Final(digest, &ctx);
5122
5123 // pointer to last decoded 16 octets
5124 last = value;
5125
5126 while (len > 0)
5127 {
5128 // calculate a new pad based on the last decoded block
5129 if (d >= sizeof(digest))
5130 {
5131 MD5_Init(&ctx);
5132 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5133 MD5_Update(&ctx, last, sizeof(digest));
5134 MD5_Final(digest, &ctx);
5135
5136 d = 0;
5137 last = value;
5138 }
5139
5140 *value++ ^= digest[d++];
5141 len--;
5142 }
5143 }
5144
5145 int find_filter(char const *name, size_t len)
5146 {
5147 int free = -1;
5148 int i;
5149
5150 for (i = 0; i < MAXFILTER; i++)
5151 {
5152 if (!*ip_filters[i].name)
5153 {
5154 if (free < 0)
5155 free = i;
5156
5157 continue;
5158 }
5159
5160 if (strlen(ip_filters[i].name) != len)
5161 continue;
5162
5163 if (!strncmp(ip_filters[i].name, name, len))
5164 return i;
5165 }
5166
5167 return free;
5168 }
5169
5170 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5171 {
5172 switch (p->op)
5173 {
5174 case FILTER_PORT_OP_EQ: return port == p->port;
5175 case FILTER_PORT_OP_NEQ: return port != p->port;
5176 case FILTER_PORT_OP_GT: return port > p->port;
5177 case FILTER_PORT_OP_LT: return port < p->port;
5178 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5179 }
5180
5181 return 0;
5182 }
5183
5184 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5185 {
5186 switch (op)
5187 {
5188 case FILTER_FLAG_OP_ANY:
5189 return (flags & sflags) || (~flags & cflags);
5190
5191 case FILTER_FLAG_OP_ALL:
5192 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5193
5194 case FILTER_FLAG_OP_EST:
5195 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5196 }
5197
5198 return 0;
5199 }
5200
5201 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5202 {
5203 uint16_t frag_offset;
5204 uint8_t proto;
5205 in_addr_t src_ip;
5206 in_addr_t dst_ip;
5207 uint16_t src_port = 0;
5208 uint16_t dst_port = 0;
5209 uint8_t flags = 0;
5210 ip_filter_rulet *rule;
5211
5212 if (len < 20) // up to end of destination address
5213 return 0;
5214
5215 if ((*buf >> 4) != 4) // IPv4
5216 return 0;
5217
5218 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5219 proto = buf[9];
5220 src_ip = *(in_addr_t *) (buf + 12);
5221 dst_ip = *(in_addr_t *) (buf + 16);
5222
5223 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5224 {
5225 int l = (buf[0] & 0xf) * 4; // length of IP header
5226 if (len < l + 4) // ports
5227 return 0;
5228
5229 src_port = ntohs(*(uint16_t *) (buf + l));
5230 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5231 if (proto == IPPROTO_TCP)
5232 {
5233 if (len < l + 14) // flags
5234 return 0;
5235
5236 flags = buf[l + 13] & 0x3f;
5237 }
5238 }
5239
5240 for (rule = ip_filters[filter].rules; rule->action; rule++)
5241 {
5242 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5243 continue;
5244
5245 if (rule->src_wild != INADDR_BROADCAST &&
5246 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5247 continue;
5248
5249 if (rule->dst_wild != INADDR_BROADCAST &&
5250 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5251 continue;
5252
5253 if (frag_offset)
5254 {
5255 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5256 continue;
5257 }
5258 else
5259 {
5260 if (rule->frag)
5261 continue;
5262
5263 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5264 {
5265 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5266 continue;
5267
5268 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5269 continue;
5270
5271 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5272 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5273 continue;
5274 }
5275 }
5276
5277 // matched
5278 rule->counter++;
5279 return rule->action == FILTER_ACTION_PERMIT;
5280 }
5281
5282 // default deny
5283 return 0;
5284 }