logging
[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 1.122 2005-08-11 06:18:56 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 LOG(3, s, t, "IPCP: send ConfigReq\n");
1588
1589 if (!session[s].unique_id)
1590 {
1591 if (!++last_id) ++last_id; // skip zero
1592 session[s].unique_id = last_id;
1593 }
1594
1595 q = makeppp(buf,sizeof(buf), 0, 0, s, t, PPPIPCP);
1596 if (!q) return;
1597
1598 *q = ConfigReq;
1599 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1600 *(uint16_t *) (q + 2) = htons(10); // packet length
1601 q[4] = 3; // ip address option
1602 q[5] = 6; // option length
1603 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1604 config->bind_address ? config->bind_address :
1605 my_address; // send my IP
1606
1607 tunnelsend(buf, 10 + (q - buf), t); // send it
1608 }
1609
1610 void sendipv6cp(sessionidt s, tunnelidt t)
1611 {
1612 uint8_t buf[MAXCONTROL];
1613 uint8_t *q;
1614
1615 CSTAT(sendipv6cp);
1616 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1617
1618 q = makeppp(buf,sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1619 if (!q) return;
1620
1621 *q = ConfigReq;
1622 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1623 // only send one type
1624 // of request
1625 *(uint16_t *) (q + 2) = htons(14);
1626 q[4] = 1; // interface identifier option
1627 q[5] = 10; // option length
1628 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1629 *(uint32_t *) (q + 10) = 0;
1630 q[13] = 1;
1631
1632 tunnelsend(buf, 14 + (q - buf), t); // send it
1633 }
1634
1635 static void sessionclear(sessionidt s)
1636 {
1637 memset(&session[s], 0, sizeof(session[s]));
1638 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1639 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1640
1641 session[s].tunnel = T_FREE; // Mark it as free.
1642 session[s].next = sessionfree;
1643 sessionfree = s;
1644 }
1645
1646 // kill a session now
1647 void sessionkill(sessionidt s, char *reason)
1648 {
1649
1650 CSTAT(sessionkill);
1651
1652 if (!session[s].opened) // not alive
1653 return;
1654
1655 if (session[s].next)
1656 {
1657 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1658 return;
1659 }
1660
1661 session[s].die = TIME;
1662 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1663 if (sess_local[s].radius)
1664 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1665
1666 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1667 sessionclear(s);
1668 cluster_send_session(s);
1669 }
1670
1671 static void tunnelclear(tunnelidt t)
1672 {
1673 if (!t) return;
1674 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1675 tunnel[t].state = TUNNELFREE;
1676 }
1677
1678 // kill a tunnel now
1679 static void tunnelkill(tunnelidt t, char *reason)
1680 {
1681 sessionidt s;
1682 controlt *c;
1683
1684 CSTAT(tunnelkill);
1685
1686 tunnel[t].state = TUNNELDIE;
1687
1688 // free control messages
1689 while ((c = tunnel[t].controls))
1690 {
1691 controlt * n = c->next;
1692 tunnel[t].controls = n;
1693 tunnel[t].controlc--;
1694 c->next = controlfree;
1695 controlfree = c;
1696 }
1697 // kill sessions
1698 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1699 if (session[s].tunnel == t)
1700 sessionkill(s, reason);
1701
1702 // free tunnel
1703 tunnelclear(t);
1704 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1705 cli_tunnel_actions[t].action = 0;
1706 cluster_send_tunnel(t);
1707 }
1708
1709 // shut down a tunnel cleanly
1710 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1711 {
1712 sessionidt s;
1713
1714 CSTAT(tunnelshutdown);
1715
1716 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1717 {
1718 // never set up, can immediately kill
1719 tunnelkill(t, reason);
1720 return;
1721 }
1722 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1723
1724 // close session
1725 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1726 if (session[s].tunnel == t)
1727 sessionshutdown(s, reason, 0, 0);
1728
1729 tunnel[t].state = TUNNELDIE;
1730 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1731 cluster_send_tunnel(t);
1732 // TBA - should we wait for sessions to stop?
1733 if (result)
1734 {
1735 controlt *c = controlnew(4); // sending StopCCN
1736 if (error)
1737 {
1738 uint8_t buf[64];
1739 int l = 4;
1740 *(uint16_t *) buf = htons(result);
1741 *(uint16_t *) (buf+2) = htons(error);
1742 if (msg)
1743 {
1744 int m = strlen(msg);
1745 if (m + 4 > sizeof(buf))
1746 m = sizeof(buf) - 4;
1747
1748 memcpy(buf+4, msg, m);
1749 l += m;
1750 }
1751
1752 controlb(c, 1, buf, l, 1);
1753 }
1754 else
1755 control16(c, 1, result, 1);
1756
1757 control16(c, 9, t, 1); // assigned tunnel (our end)
1758 controladd(c, 0, t); // send the message
1759 }
1760 }
1761
1762 // read and process packet on tunnel (UDP)
1763 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1764 {
1765 uint8_t *chapresponse = NULL;
1766 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1767 uint8_t *p = buf + 2;
1768
1769
1770 CSTAT(processudp);
1771
1772 udp_rx += len;
1773 udp_rx_pkt++;
1774 LOG_HEX(5, "UDP Data", buf, len);
1775 STAT(tunnel_rx_packets);
1776 INC_STAT(tunnel_rx_bytes, len);
1777 if (len < 6)
1778 {
1779 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1780 STAT(tunnel_rx_errors);
1781 return;
1782 }
1783 if ((buf[1] & 0x0F) != 2)
1784 {
1785 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1786 STAT(tunnel_rx_errors);
1787 return;
1788 }
1789 if (*buf & 0x40)
1790 { // length
1791 l = ntohs(*(uint16_t *) p);
1792 p += 2;
1793 }
1794 t = ntohs(*(uint16_t *) p);
1795 p += 2;
1796 s = ntohs(*(uint16_t *) p);
1797 p += 2;
1798 if (s >= MAXSESSION)
1799 {
1800 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1801 STAT(tunnel_rx_errors);
1802 return;
1803 }
1804 if (t >= MAXTUNNEL)
1805 {
1806 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1807 STAT(tunnel_rx_errors);
1808 return;
1809 }
1810 if (*buf & 0x08)
1811 { // ns/nr
1812 ns = ntohs(*(uint16_t *) p);
1813 p += 2;
1814 nr = ntohs(*(uint16_t *) p);
1815 p += 2;
1816 }
1817 if (*buf & 0x02)
1818 { // offset
1819 uint16_t o = ntohs(*(uint16_t *) p);
1820 p += o + 2;
1821 }
1822 if ((p - buf) > l)
1823 {
1824 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1825 STAT(tunnel_rx_errors);
1826 return;
1827 }
1828 l -= (p - buf);
1829 if (*buf & 0x80)
1830 { // control
1831 uint16_t message = 0xFFFF; // message type
1832 uint8_t fatal = 0;
1833 uint8_t mandatory = 0;
1834 uint16_t asession = 0; // assigned session
1835 uint32_t amagic = 0; // magic number
1836 uint8_t aflags = 0; // flags from last LCF
1837 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1838 char called[MAXTEL] = ""; // called number
1839 char calling[MAXTEL] = ""; // calling number
1840
1841 if (!config->cluster_iam_master)
1842 {
1843 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1844 return;
1845 }
1846
1847 // control messages must have bits 0x80|0x40|0x08
1848 // (type, length and sequence) set, and bits 0x02|0x01
1849 // (offset and priority) clear
1850 if ((*buf & 0xCB) != 0xC8)
1851 {
1852 LOG(1, s, t, "Bad control header %02X\n", *buf);
1853 STAT(tunnel_rx_errors);
1854 return;
1855 }
1856
1857 // check for duplicate tunnel open message
1858 if (!t && ns == 0)
1859 {
1860 int i;
1861
1862 //
1863 // Is this a duplicate of the first packet? (SCCRQ)
1864 //
1865 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1866 {
1867 if (tunnel[i].state != TUNNELOPENING ||
1868 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1869 tunnel[i].port != ntohs(addr->sin_port) )
1870 continue;
1871 t = i;
1872 LOG(3, s, t, "Duplicate SCCRQ?\n");
1873 break;
1874 }
1875 }
1876
1877 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1878 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1879
1880 // if no tunnel specified, assign one
1881 if (!t)
1882 {
1883 if (!(t = new_tunnel()))
1884 {
1885 LOG(1, 0, 0, "No more tunnels\n");
1886 STAT(tunnel_overflow);
1887 return;
1888 }
1889 tunnelclear(t);
1890 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1891 tunnel[t].port = ntohs(addr->sin_port);
1892 tunnel[t].window = 4; // default window
1893 STAT(tunnel_created);
1894 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1895 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1896 }
1897
1898 // If the 'ns' just received is not the 'nr' we're
1899 // expecting, just send an ack and drop it.
1900 //
1901 // if 'ns' is less, then we got a retransmitted packet.
1902 // if 'ns' is greater than missed a packet. Either way
1903 // we should ignore it.
1904 if (ns != tunnel[t].nr)
1905 {
1906 // is this the sequence we were expecting?
1907 STAT(tunnel_rx_errors);
1908 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1909 t, ns, tunnel[t].nr);
1910
1911 if (l) // Is this not a ZLB?
1912 controlnull(t);
1913 return;
1914 }
1915
1916 // This is used to time out old tunnels
1917 tunnel[t].lastrec = time_now;
1918
1919 // check sequence of this message
1920 {
1921 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1922 // some to clear maybe?
1923 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1924 {
1925 controlt *c = tunnel[t].controls;
1926 tunnel[t].controls = c->next;
1927 tunnel[t].controlc--;
1928 c->next = controlfree;
1929 controlfree = c;
1930 skip--;
1931 tunnel[t].try = 0; // we have progress
1932 }
1933
1934 // receiver advance (do here so quoted correctly in any sends below)
1935 if (l) tunnel[t].nr = (ns + 1);
1936 if (skip < 0) skip = 0;
1937 if (skip < tunnel[t].controlc)
1938 {
1939 // some control packets can now be sent that were previous stuck out of window
1940 int tosend = tunnel[t].window - skip;
1941 controlt *c = tunnel[t].controls;
1942 while (c && skip)
1943 {
1944 c = c->next;
1945 skip--;
1946 }
1947 while (c && tosend)
1948 {
1949 tunnel[t].try = 0; // first send
1950 tunnelsend(c->buf, c->length, t);
1951 c = c->next;
1952 tosend--;
1953 }
1954 }
1955 if (!tunnel[t].controlc)
1956 tunnel[t].retry = 0; // caught up
1957 }
1958 if (l)
1959 { // if not a null message
1960 int result = 0;
1961 int error = 0;
1962 char *msg = 0;
1963
1964 // process AVPs
1965 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1966 {
1967 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1968 uint8_t *b = p;
1969 uint8_t flags = *p;
1970 uint16_t mtype;
1971 if (n > l)
1972 {
1973 LOG(1, s, t, "Invalid length in AVP\n");
1974 STAT(tunnel_rx_errors);
1975 return;
1976 }
1977 p += n; // next
1978 l -= n;
1979 if (flags & 0x3C) // reserved bits, should be clear
1980 {
1981 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1982 fatal = flags;
1983 result = 2; // general error
1984 error = 3; // reserved field non-zero
1985 msg = 0;
1986 continue; // next
1987 }
1988 b += 2;
1989 if (*(uint16_t *) (b))
1990 {
1991 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1992 fatal = flags;
1993 result = 2; // general error
1994 error = 6; // generic vendor-specific error
1995 msg = "unsupported vendor-specific";
1996 continue; // next
1997 }
1998 b += 2;
1999 mtype = ntohs(*(uint16_t *) (b));
2000 b += 2;
2001 n -= 6;
2002
2003 if (flags & 0x40)
2004 {
2005 uint16_t orig_len;
2006
2007 // handle hidden AVPs
2008 if (!*config->l2tpsecret)
2009 {
2010 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2011 fatal = flags;
2012 result = 2; // general error
2013 error = 6; // generic vendor-specific error
2014 msg = "secret not specified";
2015 continue;
2016 }
2017 if (!session[s].random_vector_length)
2018 {
2019 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2020 fatal = flags;
2021 result = 2; // general error
2022 error = 6; // generic
2023 msg = "no random vector";
2024 continue;
2025 }
2026 if (n < 8)
2027 {
2028 LOG(2, s, t, "Short hidden AVP.\n");
2029 fatal = flags;
2030 result = 2; // general error
2031 error = 2; // length is wrong
2032 msg = 0;
2033 continue;
2034 }
2035
2036 // Unhide the AVP
2037 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2038
2039 orig_len = ntohs(*(uint16_t *) b);
2040 if (orig_len > n + 2)
2041 {
2042 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2043 orig_len, n);
2044
2045 fatal = flags;
2046 result = 2; // general error
2047 error = 2; // length is wrong
2048 msg = 0;
2049 continue;
2050 }
2051
2052 b += 2;
2053 n = orig_len;
2054 }
2055
2056 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2057 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2058
2059 switch (mtype)
2060 {
2061 case 0: // message type
2062 message = ntohs(*(uint16_t *) b);
2063 mandatory = flags & 0x80;
2064 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2065 break;
2066 case 1: // result code
2067 {
2068 uint16_t rescode = ntohs(*(uint16_t *) b);
2069 const char* resdesc = "(unknown)";
2070 if (message == 4)
2071 { /* StopCCN */
2072 resdesc = l2tp_stopccn_result_code(rescode);
2073 }
2074 else if (message == 14)
2075 { /* CDN */
2076 resdesc = l2tp_cdn_result_code(rescode);
2077 }
2078
2079 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2080 if (n >= 4)
2081 {
2082 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2083 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2084 }
2085 if (n > 4)
2086 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2087
2088 break;
2089 }
2090 break;
2091 case 2: // protocol version
2092 {
2093 version = ntohs(*(uint16_t *) (b));
2094 LOG(4, s, t, " Protocol version = %d\n", version);
2095 if (version && version != 0x0100)
2096 { // allow 0.0 and 1.0
2097 LOG(1, s, t, " Bad protocol version %04X\n", version);
2098 fatal = flags;
2099 result = 5; // unspported protocol version
2100 error = 0x0100; // supported version
2101 msg = 0;
2102 continue; // next
2103 }
2104 }
2105 break;
2106 case 3: // framing capabilities
2107 // LOG(4, s, t, "Framing capabilities\n");
2108 break;
2109 case 4: // bearer capabilities
2110 // LOG(4, s, t, "Bearer capabilities\n");
2111 break;
2112 case 5: // tie breaker
2113 // We never open tunnels, so we don't care about tie breakers
2114 // LOG(4, s, t, "Tie breaker\n");
2115 continue;
2116 case 6: // firmware revision
2117 // LOG(4, s, t, "Firmware revision\n");
2118 break;
2119 case 7: // host name
2120 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2121 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2122 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2123 // TBA - to send to RADIUS
2124 break;
2125 case 8: // vendor name
2126 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2127 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2128 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2129 break;
2130 case 9: // assigned tunnel
2131 tunnel[t].far = ntohs(*(uint16_t *) (b));
2132 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2133 break;
2134 case 10: // rx window
2135 tunnel[t].window = ntohs(*(uint16_t *) (b));
2136 if (!tunnel[t].window)
2137 tunnel[t].window = 1; // window of 0 is silly
2138 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2139 break;
2140 case 11: // Challenge
2141 {
2142 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2143 build_chap_response(b, 2, n, &chapresponse);
2144 }
2145 break;
2146 case 13: // Response
2147 // Why did they send a response? We never challenge.
2148 LOG(2, s, t, " received unexpected challenge response\n");
2149 break;
2150
2151 case 14: // assigned session
2152 asession = session[s].far = ntohs(*(uint16_t *) (b));
2153 LOG(4, s, t, " assigned session = %d\n", asession);
2154 break;
2155 case 15: // call serial number
2156 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2157 break;
2158 case 18: // bearer type
2159 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2160 // TBA - for RADIUS
2161 break;
2162 case 19: // framing type
2163 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2164 // TBA
2165 break;
2166 case 21: // called number
2167 memset(called, 0, sizeof(called));
2168 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2169 LOG(4, s, t, " Called <%s>\n", called);
2170 break;
2171 case 22: // calling number
2172 memset(calling, 0, sizeof(calling));
2173 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2174 LOG(4, s, t, " Calling <%s>\n", calling);
2175 break;
2176 case 23: // subtype
2177 break;
2178 case 24: // tx connect speed
2179 if (n == 4)
2180 {
2181 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2182 }
2183 else
2184 {
2185 // AS5300s send connect speed as a string
2186 char tmp[30];
2187 memset(tmp, 0, sizeof(tmp));
2188 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2189 session[s].tx_connect_speed = atol(tmp);
2190 }
2191 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2192 break;
2193 case 38: // rx connect speed
2194 if (n == 4)
2195 {
2196 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2197 }
2198 else
2199 {
2200 // AS5300s send connect speed as a string
2201 char tmp[30];
2202 memset(tmp, 0, sizeof(tmp));
2203 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2204 session[s].rx_connect_speed = atol(tmp);
2205 }
2206 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2207 break;
2208 case 25: // Physical Channel ID
2209 {
2210 uint32_t tmp = ntohl(*(uint32_t *) b);
2211 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2212 break;
2213 }
2214 case 29: // Proxy Authentication Type
2215 {
2216 uint16_t atype = ntohs(*(uint16_t *)b);
2217 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2218 break;
2219 }
2220 case 30: // Proxy Authentication Name
2221 {
2222 char authname[64];
2223 memset(authname, 0, sizeof(authname));
2224 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2225 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2226 authname);
2227 break;
2228 }
2229 case 31: // Proxy Authentication Challenge
2230 {
2231 LOG(4, s, t, " Proxy Auth Challenge\n");
2232 break;
2233 }
2234 case 32: // Proxy Authentication ID
2235 {
2236 uint16_t authid = ntohs(*(uint16_t *)(b));
2237 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2238 break;
2239 }
2240 case 33: // Proxy Authentication Response
2241 LOG(4, s, t, " Proxy Auth Response\n");
2242 break;
2243 case 27: // last sent lcp
2244 { // find magic number
2245 uint8_t *p = b, *e = p + n;
2246 while (p + 1 < e && p[1] && p + p[1] <= e)
2247 {
2248 if (*p == 5 && p[1] == 6) // Magic-Number
2249 amagic = ntohl(*(uint32_t *) (p + 2));
2250 else if (*p == 7) // Protocol-Field-Compression
2251 aflags |= SESSIONPFC;
2252 else if (*p == 8) // Address-and-Control-Field-Compression
2253 aflags |= SESSIONACFC;
2254 p += p[1];
2255 }
2256 }
2257 break;
2258 case 28: // last recv lcp confreq
2259 break;
2260 case 26: // Initial Received LCP CONFREQ
2261 break;
2262 case 39: // seq required - we control it as an LNS anyway...
2263 break;
2264 case 36: // Random Vector
2265 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2266 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2267 if (n > sizeof(session[s].random_vector))
2268 n = sizeof(session[s].random_vector);
2269 memcpy(session[s].random_vector, b, n);
2270 session[s].random_vector_length = n;
2271 break;
2272 default:
2273 {
2274 static char e[] = "unknown AVP 0xXXXX";
2275 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2276 fatal = flags;
2277 result = 2; // general error
2278 error = 8; // unknown mandatory AVP
2279 sprintf((msg = e) + 14, "%04x", mtype);
2280 continue; // next
2281 }
2282 }
2283 }
2284 // process message
2285 if (fatal & 0x80)
2286 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2287 else
2288 switch (message)
2289 {
2290 case 1: // SCCRQ - Start Control Connection Request
2291 tunnel[t].state = TUNNELOPENING;
2292 if (main_quit != QUIT_SHUTDOWN)
2293 {
2294 controlt *c = controlnew(2); // sending SCCRP
2295 control16(c, 2, version, 1); // protocol version
2296 control32(c, 3, 3, 1); // framing
2297 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2298 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2299 control16(c, 9, t, 1); // assigned tunnel
2300 controladd(c, 0, t); // send the resply
2301 }
2302 else
2303 {
2304 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2305 }
2306 break;
2307 case 2: // SCCRP
2308 tunnel[t].state = TUNNELOPEN;
2309 break;
2310 case 3: // SCCN
2311 tunnel[t].state = TUNNELOPEN;
2312 controlnull(t); // ack
2313 break;
2314 case 4: // StopCCN
2315 controlnull(t); // ack
2316 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2317 break;
2318 case 6: // HELLO
2319 controlnull(t); // simply ACK
2320 break;
2321 case 7: // OCRQ
2322 // TBA
2323 break;
2324 case 8: // OCRO
2325 // TBA
2326 break;
2327 case 9: // OCCN
2328 // TBA
2329 break;
2330 case 10: // ICRQ
2331 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2332 {
2333 controlt *c = controlnew(11); // ICRP
2334
2335 s = sessionfree;
2336 sessionfree = session[s].next;
2337 memset(&session[s], 0, sizeof(session[s]));
2338
2339 if (s > config->cluster_highest_sessionid)
2340 config->cluster_highest_sessionid = s;
2341
2342 session[s].opened = time_now;
2343 session[s].tunnel = t;
2344 session[s].far = asession;
2345 session[s].last_packet = time_now;
2346 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2347 control16(c, 14, s, 1); // assigned session
2348 controladd(c, asession, t); // send the reply
2349
2350 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2351 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2352
2353 session[s].ppp.phase = Establish;
2354 session[s].ppp.lcp = Starting;
2355
2356 STAT(session_created);
2357 break;
2358 }
2359
2360 {
2361 controlt *c = controlnew(14); // CDN
2362 if (!sessionfree)
2363 {
2364 STAT(session_overflow);
2365 LOG(1, 0, t, "No free sessions\n");
2366 control16(c, 1, 4, 0); // temporary lack of resources
2367 }
2368 else
2369 control16(c, 1, 2, 7); // shutting down, try another
2370
2371 controladd(c, asession, t); // send the message
2372 }
2373 return;
2374 case 11: // ICRP
2375 // TBA
2376 break;
2377 case 12: // ICCN
2378 if (amagic == 0) amagic = time_now;
2379 session[s].magic = amagic; // set magic number
2380 session[s].l2tp_flags = aflags; // set flags received
2381 controlnull(t); // ack
2382
2383 // start LCP
2384 sendlcp(s, t, config->radius_authprefer);
2385 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2386 sess_local[s].lcp.conf_sent = 1;
2387 sess_local[s].lcp.nak_sent = 0;
2388 sess_local[s].lcp_authtype = config->radius_authprefer;
2389 session[s].ppp.lcp = RequestSent;
2390
2391 break;
2392 case 14: // CDN
2393 controlnull(t); // ack
2394 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2395 break;
2396 case 0xFFFF:
2397 LOG(1, s, t, "Missing message type\n");
2398 break;
2399 default:
2400 STAT(tunnel_rx_errors);
2401 if (mandatory)
2402 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2403 else
2404 LOG(1, s, t, "Unknown message type %d\n", message);
2405 break;
2406 }
2407 if (chapresponse) free(chapresponse);
2408 cluster_send_tunnel(t);
2409 }
2410 else
2411 {
2412 LOG(4, s, t, " Got a ZLB ack\n");
2413 }
2414 }
2415 else
2416 { // data
2417 uint16_t prot;
2418
2419 LOG_HEX(5, "Receive Tunnel Data", p, l);
2420 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2421 { // HDLC address header, discard
2422 p += 2;
2423 l -= 2;
2424 }
2425 if (l < 2)
2426 {
2427 LOG(1, s, t, "Short ppp length %d\n", l);
2428 STAT(tunnel_rx_errors);
2429 return;
2430 }
2431 if (*p & 1)
2432 {
2433 prot = *p++;
2434 l--;
2435 }
2436 else
2437 {
2438 prot = ntohs(*(uint16_t *) p);
2439 p += 2;
2440 l -= 2;
2441 }
2442
2443 if (s && !session[s].opened) // Is something wrong??
2444 {
2445 if (!config->cluster_iam_master)
2446 {
2447 // Pass it off to the master to deal with..
2448 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2449 return;
2450 }
2451
2452
2453 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2454 STAT(tunnel_rx_errors);
2455 return;
2456 }
2457
2458 if (prot == PPPPAP)
2459 {
2460 session[s].last_packet = time_now;
2461 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2462 processpap(s, t, p, l);
2463 }
2464 else if (prot == PPPCHAP)
2465 {
2466 session[s].last_packet = time_now;
2467 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2468 processchap(s, t, p, l);
2469 }
2470 else if (prot == PPPLCP)
2471 {
2472 session[s].last_packet = time_now;
2473 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2474 processlcp(s, t, p, l);
2475 }
2476 else if (prot == PPPIPCP)
2477 {
2478 session[s].last_packet = time_now;
2479 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2480 processipcp(s, t, p, l);
2481 }
2482 else if (prot == PPPIPV6CP)
2483 {
2484 session[s].last_packet = time_now;
2485 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2486 processipv6cp(s, t, p, l);
2487 }
2488 else if (prot == PPPCCP)
2489 {
2490 session[s].last_packet = time_now;
2491 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2492 processccp(s, t, p, l);
2493 }
2494 else if (prot == PPPIP)
2495 {
2496 if (session[s].die)
2497 {
2498 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2499 return; // closing session, PPP not processed
2500 }
2501
2502 session[s].last_packet = time_now;
2503 if (session[s].walled_garden && !config->cluster_iam_master)
2504 {
2505 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2506 return;
2507 }
2508
2509 processipin(s, t, p, l);
2510 }
2511 else if (prot == PPPIPV6)
2512 {
2513 if (!config->ipv6_prefix.s6_addr[0])
2514 {
2515 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2516 return;
2517 }
2518 if (session[s].die)
2519 {
2520 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2521 return; // closing session, PPP not processed
2522 }
2523
2524 session[s].last_packet = time_now;
2525 if (session[s].walled_garden && !config->cluster_iam_master)
2526 {
2527 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2528 return;
2529 }
2530
2531 processipv6in(s, t, p, l);
2532 }
2533 else
2534 {
2535 STAT(tunnel_rx_errors);
2536 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2537 }
2538 }
2539 }
2540
2541 // read and process packet on tun
2542 static void processtun(uint8_t * buf, int len)
2543 {
2544 LOG_HEX(5, "Receive TUN Data", buf, len);
2545 STAT(tun_rx_packets);
2546 INC_STAT(tun_rx_bytes, len);
2547
2548 CSTAT(processtun);
2549
2550 eth_rx_pkt++;
2551 eth_rx += len;
2552 if (len < 22)
2553 {
2554 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2555 STAT(tun_rx_errors);
2556 return;
2557 }
2558
2559 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2560 processipout(buf, len);
2561 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2562 && config->ipv6_prefix.s6_addr[0])
2563 processipv6out(buf, len);
2564
2565 // Else discard.
2566 }
2567
2568 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2569 // that we look at the whole of the tunnel, radius and session tables
2570 // every second
2571 static void regular_cleanups(double period)
2572 {
2573 // Next tunnel, radius and session to check for actions on.
2574 static tunnelidt t = 0;
2575 static int r = 0;
2576 static sessionidt s = 0;
2577
2578 int t_actions = 0;
2579 int r_actions = 0;
2580 int s_actions = 0;
2581
2582 int t_slice;
2583 int r_slice;
2584 int s_slice;
2585
2586 int i;
2587 int a;
2588
2589 // divide up tables into slices based on the last run
2590 t_slice = config->cluster_highest_tunnelid * period;
2591 r_slice = (MAXRADIUS - 1) * period;
2592 s_slice = config->cluster_highest_sessionid * period;
2593
2594 if (t_slice < 1)
2595 t_slice = 1;
2596 else if (t_slice > config->cluster_highest_tunnelid)
2597 t_slice = config->cluster_highest_tunnelid;
2598
2599 if (r_slice < 1)
2600 r_slice = 1;
2601 else if (r_slice > (MAXRADIUS - 1))
2602 r_slice = MAXRADIUS - 1;
2603
2604 if (s_slice < 1)
2605 s_slice = 1;
2606 else if (s_slice > config->cluster_highest_sessionid)
2607 s_slice = config->cluster_highest_sessionid;
2608
2609 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2610
2611 for (i = 0; i < t_slice; i++)
2612 {
2613 t++;
2614 if (t > config->cluster_highest_tunnelid)
2615 t = 1;
2616
2617 // check for expired tunnels
2618 if (tunnel[t].die && tunnel[t].die <= TIME)
2619 {
2620 STAT(tunnel_timeout);
2621 tunnelkill(t, "Expired");
2622 t_actions++;
2623 continue;
2624 }
2625 // check for message resend
2626 if (tunnel[t].retry && tunnel[t].controlc)
2627 {
2628 // resend pending messages as timeout on reply
2629 if (tunnel[t].retry <= TIME)
2630 {
2631 controlt *c = tunnel[t].controls;
2632 uint8_t w = tunnel[t].window;
2633 tunnel[t].try++; // another try
2634 if (tunnel[t].try > 5)
2635 tunnelkill(t, "Timeout on control message"); // game over
2636 else
2637 while (c && w--)
2638 {
2639 tunnelsend(c->buf, c->length, t);
2640 c = c->next;
2641 }
2642
2643 t_actions++;
2644 }
2645 }
2646 // Send hello
2647 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2648 {
2649 controlt *c = controlnew(6); // sending HELLO
2650 controladd(c, 0, t); // send the message
2651 LOG(3, 0, t, "Sending HELLO message\n");
2652 t_actions++;
2653 }
2654
2655 // Check for tunnel changes requested from the CLI
2656 if ((a = cli_tunnel_actions[t].action))
2657 {
2658 cli_tunnel_actions[t].action = 0;
2659 if (a & CLI_TUN_KILL)
2660 {
2661 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2662 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2663 t_actions++;
2664 }
2665 }
2666 }
2667
2668 for (i = 0; i < r_slice; i++)
2669 {
2670 r++;
2671 if (r >= MAXRADIUS)
2672 r = 1;
2673
2674 if (!radius[r].state)
2675 continue;
2676
2677 if (radius[r].retry <= TIME)
2678 {
2679 radiusretry(r);
2680 r_actions++;
2681 }
2682 }
2683
2684 for (i = 0; i < s_slice; i++)
2685 {
2686 s++;
2687 if (s > config->cluster_highest_sessionid)
2688 s = 1;
2689
2690 if (!session[s].opened) // Session isn't in use
2691 continue;
2692
2693 // check for expired sessions
2694 if (session[s].die)
2695 {
2696 if (session[s].die <= TIME)
2697 {
2698 sessionkill(s, "Expired");
2699 s_actions++;
2700 }
2701 continue;
2702 }
2703
2704 // PPP timeouts
2705 if (sess_local[s].lcp.restart <= time_now)
2706 {
2707 int next_state = session[s].ppp.lcp;
2708 switch (session[s].ppp.lcp)
2709 {
2710 case RequestSent:
2711 case AckReceived:
2712 next_state = RequestSent;
2713
2714 case AckSent:
2715 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2716 {
2717 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2718 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2719 sess_local[s].lcp.conf_sent++;
2720 sendlcp(s, t, sess_local[s].lcp_authtype);
2721 change_state(s, lcp, next_state);
2722 }
2723 else
2724 {
2725 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2726 STAT(session_timeout);
2727 }
2728
2729 s_actions++;
2730 }
2731
2732 if (session[s].die)
2733 continue;
2734 }
2735
2736 if (sess_local[s].ipcp.restart <= time_now)
2737 {
2738 int next_state = session[s].ppp.ipcp;
2739 switch (session[s].ppp.ipcp)
2740 {
2741 case RequestSent:
2742 case AckReceived:
2743 next_state = RequestSent;
2744
2745 case AckSent:
2746 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2747 {
2748 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2749 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2750 sess_local[s].ipcp.conf_sent++;
2751 sendipcp(s, t);
2752 change_state(s, ipcp, next_state);
2753 }
2754 else
2755 {
2756 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2757 STAT(session_timeout);
2758 }
2759
2760 s_actions++;
2761 }
2762
2763 if (session[s].die)
2764 continue;
2765 }
2766
2767 if (sess_local[s].ipv6cp.restart <= time_now)
2768 {
2769 int next_state = session[s].ppp.ipv6cp;
2770 switch (session[s].ppp.ipv6cp)
2771 {
2772 case RequestSent:
2773 case AckReceived:
2774 next_state = RequestSent;
2775
2776 case AckSent:
2777 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2778 {
2779 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2780 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2781 sess_local[s].ipv6cp.conf_sent++;
2782 sendipv6cp(s, t);
2783 change_state(s, ipv6cp, next_state);
2784 }
2785 else
2786 {
2787 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2788 change_state(s, ipv6cp, Stopped);
2789 }
2790
2791 s_actions++;
2792 }
2793 }
2794
2795 if (sess_local[s].ccp.restart <= time_now)
2796 {
2797 int next_state = session[s].ppp.ccp;
2798 switch (session[s].ppp.ccp)
2799 {
2800 case RequestSent:
2801 case AckReceived:
2802 next_state = RequestSent;
2803
2804 case AckSent:
2805 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2806 {
2807 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2808 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2809 sess_local[s].ccp.conf_sent++;
2810 sendccp(s, t);
2811 change_state(s, ccp, next_state);
2812 }
2813 else
2814 {
2815 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2816 change_state(s, ccp, Stopped);
2817 }
2818
2819 s_actions++;
2820 }
2821 }
2822
2823 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2824 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2825 {
2826 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2827 STAT(session_timeout);
2828 s_actions++;
2829 continue;
2830 }
2831
2832 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2833 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2834 {
2835 uint8_t b[MAXCONTROL] = {0};
2836
2837 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2838 if (!q) continue;
2839
2840 *q = EchoReq;
2841 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2842 *(uint16_t *)(q + 2) = htons(8); // Length
2843 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2844
2845 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2846 (int)(time_now - session[s].last_packet));
2847 tunnelsend(b, 24, session[s].tunnel); // send it
2848 s_actions++;
2849 }
2850
2851 // Check for actions requested from the CLI
2852 if ((a = cli_session_actions[s].action))
2853 {
2854 int send = 0;
2855
2856 cli_session_actions[s].action = 0;
2857 if (a & CLI_SESS_KILL)
2858 {
2859 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2860 sessionshutdown(s, "Requested by administrator.", 3, 0);
2861 a = 0; // dead, no need to check for other actions
2862 s_actions++;
2863 }
2864
2865 if (a & CLI_SESS_NOSNOOP)
2866 {
2867 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2868 session[s].snoop_ip = 0;
2869 session[s].snoop_port = 0;
2870 s_actions++;
2871 send++;
2872 }
2873 else if (a & CLI_SESS_SNOOP)
2874 {
2875 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2876 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2877 cli_session_actions[s].snoop_port);
2878
2879 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2880 session[s].snoop_port = cli_session_actions[s].snoop_port;
2881 s_actions++;
2882 send++;
2883 }
2884
2885 if (a & CLI_SESS_NOTHROTTLE)
2886 {
2887 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2888 throttle_session(s, 0, 0);
2889 s_actions++;
2890 send++;
2891 }
2892 else if (a & CLI_SESS_THROTTLE)
2893 {
2894 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2895 cli_session_actions[s].throttle_in,
2896 cli_session_actions[s].throttle_out);
2897
2898 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2899 s_actions++;
2900 send++;
2901 }
2902
2903 if (a & CLI_SESS_NOFILTER)
2904 {
2905 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2906 filter_session(s, 0, 0);
2907 s_actions++;
2908 send++;
2909 }
2910 else if (a & CLI_SESS_FILTER)
2911 {
2912 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2913 cli_session_actions[s].filter_in,
2914 cli_session_actions[s].filter_out);
2915
2916 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2917 s_actions++;
2918 send++;
2919 }
2920
2921 if (send)
2922 cluster_send_session(s);
2923 }
2924
2925 // RADIUS interim accounting
2926 if (config->radius_accounting && config->radius_interim > 0
2927 && session[s].ip && !session[s].walled_garden
2928 && !sess_local[s].radius // RADIUS already in progress
2929 && time_now - sess_local[s].last_interim >= config->radius_interim)
2930 {
2931 int rad = radiusnew(s);
2932 if (!rad)
2933 {
2934 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2935 STAT(radius_overflow);
2936 continue;
2937 }
2938
2939 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2940 session[s].user, session[s].unique_id);
2941
2942 radiussend(rad, RADIUSINTERIM);
2943 sess_local[s].last_interim = time_now;
2944 s_actions++;
2945 }
2946 }
2947
2948 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2949 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2950 }
2951
2952 //
2953 // Are we in the middle of a tunnel update, or radius
2954 // requests??
2955 //
2956 static int still_busy(void)
2957 {
2958 int i;
2959 static clockt last_talked = 0;
2960 static clockt start_busy_wait = 0;
2961
2962 if (!config->cluster_iam_master)
2963 {
2964 #ifdef BGP
2965 static time_t stopped_bgp = 0;
2966 if (bgp_configured)
2967 {
2968 if (!stopped_bgp)
2969 {
2970 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2971
2972 for (i = 0; i < BGP_NUM_PEERS; i++)
2973 if (bgp_peers[i].state == Established)
2974 bgp_stop(&bgp_peers[i]);
2975
2976 stopped_bgp = time_now;
2977
2978 // we don't want to become master
2979 cluster_send_ping(0);
2980
2981 return 1;
2982 }
2983
2984 if (time_now < (stopped_bgp + QUIT_DELAY))
2985 return 1;
2986 }
2987 #endif /* BGP */
2988
2989 return 0;
2990 }
2991
2992 if (main_quit == QUIT_SHUTDOWN)
2993 {
2994 static int dropped = 0;
2995 if (!dropped)
2996 {
2997 int i;
2998
2999 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3000 for (i = 1; i < MAXTUNNEL; i++)
3001 if (tunnel[i].ip || tunnel[i].state)
3002 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3003
3004 dropped = 1;
3005 }
3006 }
3007
3008 if (start_busy_wait == 0)
3009 start_busy_wait = TIME;
3010
3011 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3012 {
3013 if (!tunnel[i].controlc)
3014 continue;
3015
3016 if (last_talked != TIME)
3017 {
3018 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3019 last_talked = TIME;
3020 }
3021 return 1;
3022 }
3023
3024 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3025 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3026 {
3027 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3028 return 0;
3029 }
3030
3031 for (i = 1; i < MAXRADIUS; i++)
3032 {
3033 if (radius[i].state == RADIUSNULL)
3034 continue;
3035 if (radius[i].state == RADIUSWAIT)
3036 continue;
3037
3038 if (last_talked != TIME)
3039 {
3040 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3041 last_talked = TIME;
3042 }
3043 return 1;
3044 }
3045
3046 return 0;
3047 }
3048
3049 #ifdef HAVE_EPOLL
3050 # include <sys/epoll.h>
3051 #else
3052 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3053 # include "fake_epoll.h"
3054 #endif
3055
3056 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3057 #define BASE_FDS 6
3058
3059 // additional polled fds
3060 #ifdef BGP
3061 # define EXTRA_FDS BGP_NUM_PEERS
3062 #else
3063 # define EXTRA_FDS 0
3064 #endif
3065
3066 // main loop - gets packets on tun or udp and processes them
3067 static void mainloop(void)
3068 {
3069 int i;
3070 uint8_t buf[65536];
3071 clockt next_cluster_ping = 0; // send initial ping immediately
3072 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3073 int maxevent = sizeof(events)/sizeof(*events);
3074
3075 if ((epollfd = epoll_create(maxevent)) < 0)
3076 {
3077 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3078 exit(1);
3079 }
3080
3081 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3082 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3083
3084 /* setup our fds to poll for input */
3085 {
3086 static struct event_data d[BASE_FDS];
3087 struct epoll_event e;
3088
3089 e.events = EPOLLIN;
3090 i = 0;
3091
3092 d[i].type = FD_TYPE_CLI;
3093 e.data.ptr = &d[i++];
3094 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3095
3096 d[i].type = FD_TYPE_CLUSTER;
3097 e.data.ptr = &d[i++];
3098 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3099
3100 d[i].type = FD_TYPE_TUN;
3101 e.data.ptr = &d[i++];
3102 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3103
3104 d[i].type = FD_TYPE_UDP;
3105 e.data.ptr = &d[i++];
3106 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3107
3108 d[i].type = FD_TYPE_CONTROL;
3109 e.data.ptr = &d[i++];
3110 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3111
3112 d[i].type = FD_TYPE_DAE;
3113 e.data.ptr = &d[i++];
3114 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3115 }
3116
3117 #ifdef BGP
3118 signal(SIGPIPE, SIG_IGN);
3119 bgp_setup(config->as_number);
3120 if (config->bind_address)
3121 bgp_add_route(config->bind_address, 0xffffffff);
3122
3123 for (i = 0; i < BGP_NUM_PEERS; i++)
3124 {
3125 if (config->neighbour[i].name[0])
3126 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3127 config->neighbour[i].as, config->neighbour[i].keepalive,
3128 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3129 }
3130 #endif /* BGP */
3131
3132 while (!main_quit || still_busy())
3133 {
3134 int more = 0;
3135 int n;
3136
3137 if (config->reload_config)
3138 {
3139 // Update the config state based on config settings
3140 update_config();
3141 }
3142
3143 #ifdef BGP
3144 bgp_set_poll();
3145 #endif /* BGP */
3146
3147 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3148 STAT(select_called);
3149
3150 TIME = now(NULL);
3151 if (n < 0)
3152 {
3153 if (errno == EINTR ||
3154 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3155 continue;
3156
3157 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3158 break; // exit
3159 }
3160
3161 if (n)
3162 {
3163 struct sockaddr_in addr;
3164 socklen_t alen;
3165 int c, s;
3166 int udp_ready = 0;
3167 int tun_ready = 0;
3168 int cluster_ready = 0;
3169 int udp_pkts = 0;
3170 int tun_pkts = 0;
3171 int cluster_pkts = 0;
3172 #ifdef BGP
3173 uint32_t bgp_events[BGP_NUM_PEERS];
3174 memset(bgp_events, 0, sizeof(bgp_events));
3175 #endif /* BGP */
3176
3177 for (c = n, i = 0; i < c; i++)
3178 {
3179 struct event_data *d = events[i].data.ptr;
3180 switch (d->type)
3181 {
3182 case FD_TYPE_CLI: // CLI connections
3183 {
3184 int cli;
3185
3186 alen = sizeof(addr);
3187 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3188 {
3189 cli_do(cli);
3190 close(cli);
3191 }
3192 else
3193 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3194
3195 n--;
3196 break;
3197 }
3198
3199 // these are handled below, with multiple interleaved reads
3200 case FD_TYPE_CLUSTER: cluster_ready++; break;
3201 case FD_TYPE_TUN: tun_ready++; break;
3202 case FD_TYPE_UDP: udp_ready++; break;
3203
3204 case FD_TYPE_CONTROL: // nsctl commands
3205 alen = sizeof(addr);
3206 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3207 n--;
3208 break;
3209
3210 case FD_TYPE_DAE: // DAE requests
3211 alen = sizeof(addr);
3212 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3213 n--;
3214 break;
3215
3216 case FD_TYPE_RADIUS: // RADIUS response
3217 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3218 if (s >= 0 && config->cluster_iam_master)
3219 processrad(buf, s, d->index);
3220
3221 n--;
3222 break;
3223
3224 #ifdef BGP
3225 case FD_TYPE_BGP:
3226 bgp_events[d->index] = events[i].events;
3227 n--;
3228 break;
3229 #endif /* BGP */
3230
3231 default:
3232 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3233 }
3234 }
3235
3236 #ifdef BGP
3237 bgp_process(bgp_events);
3238 #endif /* BGP */
3239
3240 for (c = 0; n && c < config->multi_read_count; c++)
3241 {
3242 // L2TP
3243 if (udp_ready)
3244 {
3245 alen = sizeof(addr);
3246 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3247 {
3248 processudp(buf, s, &addr);
3249 udp_pkts++;
3250 }
3251 else
3252 {
3253 udp_ready = 0;
3254 n--;
3255 }
3256 }
3257
3258 // incoming IP
3259 if (tun_ready)
3260 {
3261 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3262 {
3263 processtun(buf, s);
3264 tun_pkts++;
3265 }
3266 else
3267 {
3268 tun_ready = 0;
3269 n--;
3270 }
3271 }
3272
3273 // cluster
3274 if (cluster_ready)
3275 {
3276 alen = sizeof(addr);
3277 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3278 {
3279 processcluster(buf, s, addr.sin_addr.s_addr);
3280 cluster_pkts++;
3281 }
3282 else
3283 {
3284 cluster_ready = 0;
3285 n--;
3286 }
3287 }
3288 }
3289
3290 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3291 STAT(multi_read_used);
3292
3293 if (c >= config->multi_read_count)
3294 {
3295 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3296 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3297
3298 STAT(multi_read_exceeded);
3299 more++;
3300 }
3301 }
3302
3303 // Runs on every machine (master and slaves).
3304 if (next_cluster_ping <= TIME)
3305 {
3306 // Check to see which of the cluster is still alive..
3307
3308 cluster_send_ping(basetime); // Only does anything if we're a slave
3309 cluster_check_master(); // ditto.
3310
3311 cluster_heartbeat(); // Only does anything if we're a master.
3312 cluster_check_slaves(); // ditto.
3313
3314 master_update_counts(); // If we're a slave, send our byte counters to our master.
3315
3316 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3317 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3318 else
3319 next_cluster_ping = TIME + config->cluster_hb_interval;
3320 }
3321
3322 if (!config->cluster_iam_master)
3323 continue;
3324
3325 // Run token bucket filtering queue..
3326 // Only run it every 1/10th of a second.
3327 {
3328 static clockt last_run = 0;
3329 if (last_run != TIME)
3330 {
3331 last_run = TIME;
3332 tbf_run_timer();
3333 }
3334 }
3335
3336 // Handle timeouts, retries etc.
3337 {
3338 static double last_clean = 0;
3339 double this_clean;
3340 double diff;
3341
3342 TIME = now(&this_clean);
3343 diff = this_clean - last_clean;
3344
3345 // Run during idle time (after we've handled
3346 // all incoming packets) or every 1/10th sec
3347 if (!more || diff > 0.1)
3348 {
3349 regular_cleanups(diff);
3350 last_clean = this_clean;
3351 }
3352 }
3353
3354 if (*config->accounting_dir)
3355 {
3356 static clockt next_acct = 0;
3357 static clockt next_shut_acct = 0;
3358
3359 if (next_acct <= TIME)
3360 {
3361 // Dump accounting data
3362 next_acct = TIME + ACCT_TIME;
3363 next_shut_acct = TIME + ACCT_SHUT_TIME;
3364 dump_acct_info(1);
3365 }
3366 else if (next_shut_acct <= TIME)
3367 {
3368 // Dump accounting data for shutdown sessions
3369 next_shut_acct = TIME + ACCT_SHUT_TIME;
3370 if (shut_acct_n)
3371 dump_acct_info(0);
3372 }
3373 }
3374 }
3375
3376 // Are we the master and shutting down??
3377 if (config->cluster_iam_master)
3378 cluster_heartbeat(); // Flush any queued changes..
3379
3380 // Ok. Notify everyone we're shutting down. If we're
3381 // the master, this will force an election.
3382 cluster_send_ping(0);
3383
3384 //
3385 // Important!!! We MUST not process any packets past this point!
3386 LOG(1, 0, 0, "Shutdown complete\n");
3387 }
3388
3389 static void stripdomain(char *host)
3390 {
3391 char *p;
3392
3393 if ((p = strchr(host, '.')))
3394 {
3395 char *domain = 0;
3396 char _domain[1024];
3397
3398 // strip off domain
3399 FILE *resolv = fopen("/etc/resolv.conf", "r");
3400 if (resolv)
3401 {
3402 char buf[1024];
3403 char *b;
3404
3405 while (fgets(buf, sizeof(buf), resolv))
3406 {
3407 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3408 continue;
3409
3410 if (!isspace(buf[6]))
3411 continue;
3412
3413 b = buf + 7;
3414 while (isspace(*b)) b++;
3415
3416 if (*b)
3417 {
3418 char *d = b;
3419 while (*b && !isspace(*b)) b++;
3420 *b = 0;
3421 if (buf[0] == 'd') // domain is canonical
3422 {
3423 domain = d;
3424 break;
3425 }
3426
3427 // first search line
3428 if (!domain)
3429 {
3430 // hold, may be subsequent domain line
3431 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3432 domain = _domain;
3433 }
3434 }
3435 }
3436
3437 fclose(resolv);
3438 }
3439
3440 if (domain)
3441 {
3442 int hl = strlen(host);
3443 int dl = strlen(domain);
3444 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3445 host[hl -dl - 1] = 0;
3446 }
3447 else
3448 {
3449 *p = 0; // everything after first dot
3450 }
3451 }
3452 }
3453
3454 // Init data structures
3455 static void initdata(int optdebug, char *optconfig)
3456 {
3457 int i;
3458
3459 if (!(config = shared_malloc(sizeof(configt))))
3460 {
3461 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3462 exit(1);
3463 }
3464
3465 memset(config, 0, sizeof(configt));
3466 time(&config->start_time);
3467 strncpy(config->config_file, optconfig, strlen(optconfig));
3468 config->debug = optdebug;
3469 config->num_tbfs = MAXTBFS;
3470 config->rl_rate = 28; // 28kbps
3471 config->cluster_master_min_adv = 1;
3472 config->ppp_restart_time = 3;
3473 config->ppp_max_configure = 10;
3474 config->ppp_max_failure = 5;
3475 strcpy(config->random_device, RANDOMDEVICE);
3476
3477 log_stream = stderr;
3478
3479 #ifdef RINGBUFFER
3480 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3481 {
3482 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3483 exit(1);
3484 }
3485 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3486 #endif
3487
3488 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3489 {
3490 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3491 exit(1);
3492 }
3493 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3494 {
3495 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3496 exit(1);
3497 }
3498 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3499 {
3500 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3501 exit(1);
3502 }
3503
3504 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3505 {
3506 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3507 exit(1);
3508 }
3509
3510 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3511 {
3512 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3513 exit(1);
3514 }
3515
3516 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3517 {
3518 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3519 exit(1);
3520 }
3521
3522 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3523 {
3524 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3525 exit(1);
3526 }
3527 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3528
3529 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3530 {
3531 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3532 exit(1);
3533 }
3534 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3535
3536 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3537 {
3538 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3539 exit(1);
3540 }
3541 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3542
3543 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3544 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3545 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3546 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3547
3548 // Put all the sessions on the free list marked as undefined.
3549 for (i = 1; i < MAXSESSION; i++)
3550 {
3551 session[i].next = i + 1;
3552 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3553 }
3554 session[MAXSESSION - 1].next = 0;
3555 sessionfree = 1;
3556
3557 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3558 for (i = 1; i < MAXTUNNEL; i++)
3559 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3560
3561 if (!*hostname)
3562 {
3563 // Grab my hostname unless it's been specified
3564 gethostname(hostname, sizeof(hostname));
3565 stripdomain(hostname);
3566 }
3567
3568 _statistics->start_time = _statistics->last_reset = time(NULL);
3569
3570 #ifdef BGP
3571 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3572 {
3573 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3574 exit(1);
3575 }
3576 #endif /* BGP */
3577 }
3578
3579 static int assign_ip_address(sessionidt s)
3580 {
3581 uint32_t i;
3582 int best = -1;
3583 time_t best_time = time_now;
3584 char *u = session[s].user;
3585 char reuse = 0;
3586
3587
3588 CSTAT(assign_ip_address);
3589
3590 for (i = 1; i < ip_pool_size; i++)
3591 {
3592 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3593 continue;
3594
3595 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3596 {
3597 best = i;
3598 reuse = 1;
3599 break;
3600 }
3601
3602 if (ip_address_pool[i].last < best_time)
3603 {
3604 best = i;
3605 if (!(best_time = ip_address_pool[i].last))
3606 break; // never used, grab this one
3607 }
3608 }
3609
3610 if (best < 0)
3611 {
3612 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3613 return 0;
3614 }
3615
3616 session[s].ip = ip_address_pool[best].address;
3617 session[s].ip_pool_index = best;
3618 ip_address_pool[best].assigned = 1;
3619 ip_address_pool[best].last = time_now;
3620 ip_address_pool[best].session = s;
3621 if (session[s].walled_garden)
3622 /* Don't track addresses of users in walled garden (note: this
3623 means that their address isn't "sticky" even if they get
3624 un-gardened). */
3625 ip_address_pool[best].user[0] = 0;
3626 else
3627 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3628
3629 STAT(ip_allocated);
3630 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3631 reuse ? "Reusing" : "Allocating", best);
3632
3633 return 1;
3634 }
3635
3636 static void free_ip_address(sessionidt s)
3637 {
3638 int i = session[s].ip_pool_index;
3639
3640
3641 CSTAT(free_ip_address);
3642
3643 if (!session[s].ip)
3644 return; // what the?
3645
3646 if (i < 0) // Is this actually part of the ip pool?
3647 i = 0;
3648
3649 STAT(ip_freed);
3650 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3651 session[s].ip = 0;
3652 ip_address_pool[i].assigned = 0;
3653 ip_address_pool[i].session = 0;
3654 ip_address_pool[i].last = time_now;
3655 }
3656
3657 //
3658 // Fsck the address pool against the session table.
3659 // Normally only called when we become a master.
3660 //
3661 // This isn't perfect: We aren't keep tracking of which
3662 // users used to have an IP address.
3663 //
3664 void rebuild_address_pool(void)
3665 {
3666 int i;
3667
3668 //
3669 // Zero the IP pool allocation, and build
3670 // a map from IP address to pool index.
3671 for (i = 1; i < MAXIPPOOL; ++i)
3672 {
3673 ip_address_pool[i].assigned = 0;
3674 ip_address_pool[i].session = 0;
3675 if (!ip_address_pool[i].address)
3676 continue;
3677
3678 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3679 }
3680
3681 for (i = 0; i < MAXSESSION; ++i)
3682 {
3683 int ipid;
3684 if (!(session[i].opened && session[i].ip))
3685 continue;
3686
3687 ipid = - lookup_ipmap(htonl(session[i].ip));
3688
3689 if (session[i].ip_pool_index < 0)
3690 {
3691 // Not allocated out of the pool.
3692 if (ipid < 1) // Not found in the pool either? good.
3693 continue;
3694
3695 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3696 i, fmtaddr(session[i].ip, 0), ipid);
3697
3698 // Fall through and process it as part of the pool.
3699 }
3700
3701
3702 if (ipid > MAXIPPOOL || ipid < 0)
3703 {
3704 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3705 ipid = -1;
3706 session[i].ip_pool_index = ipid;
3707 continue;
3708 }
3709
3710 ip_address_pool[ipid].assigned = 1;
3711 ip_address_pool[ipid].session = i;
3712 ip_address_pool[ipid].last = time_now;
3713 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3714 session[i].ip_pool_index = ipid;
3715 cache_ipmap(session[i].ip, i); // Fix the ip map.
3716 }
3717 }
3718
3719 //
3720 // Fix the address pool to match a changed session.
3721 // (usually when the master sends us an update).
3722 static void fix_address_pool(int sid)
3723 {
3724 int ipid;
3725
3726 ipid = session[sid].ip_pool_index;
3727
3728 if (ipid > ip_pool_size)
3729 return; // Ignore it. rebuild_address_pool will fix it up.
3730
3731 if (ip_address_pool[ipid].address != session[sid].ip)
3732 return; // Just ignore it. rebuild_address_pool will take care of it.
3733
3734 ip_address_pool[ipid].assigned = 1;
3735 ip_address_pool[ipid].session = sid;
3736 ip_address_pool[ipid].last = time_now;
3737 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3738 }
3739
3740 //
3741 // Add a block of addresses to the IP pool to hand out.
3742 //
3743 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3744 {
3745 int i;
3746 if (mask == 0)
3747 mask = 0xffffffff; // Host route only.
3748
3749 addr &= mask;
3750
3751 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3752 return ;
3753
3754 for (i = addr ;(i & mask) == addr; ++i)
3755 {
3756 if ((i & 0xff) == 0 || (i&0xff) == 255)
3757 continue; // Skip 0 and broadcast addresses.
3758
3759 ip_address_pool[ip_pool_size].address = i;
3760 ip_address_pool[ip_pool_size].assigned = 0;
3761 ++ip_pool_size;
3762 if (ip_pool_size >= MAXIPPOOL)
3763 {
3764 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3765 return;
3766 }
3767 }
3768 }
3769
3770 // Initialize the IP address pool
3771 static void initippool()
3772 {
3773 FILE *f;
3774 char *p;
3775 char buf[4096];
3776 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3777
3778 if (!(f = fopen(IPPOOLFILE, "r")))
3779 {
3780 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3781 exit(1);
3782 }
3783
3784 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3785 {
3786 char *pool = buf;
3787 buf[4095] = 0; // Force it to be zero terminated/
3788
3789 if (*buf == '#' || *buf == '\n')
3790 continue; // Skip comments / blank lines
3791 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3792 if ((p = (char *)strchr(buf, ':')))
3793 {
3794 in_addr_t src;
3795 *p = '\0';
3796 src = inet_addr(buf);
3797 if (src == INADDR_NONE)
3798 {
3799 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3800 exit(1);
3801 }
3802 // This entry is for a specific IP only
3803 if (src != config->bind_address)
3804 continue;
3805 *p = ':';
3806 pool = p+1;
3807 }
3808 if ((p = (char *)strchr(pool, '/')))
3809 {
3810 // It's a range
3811 int numbits = 0;
3812 in_addr_t start = 0, mask = 0;
3813
3814 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3815 *p++ = 0;
3816 if (!*p || !(numbits = atoi(p)))
3817 {
3818 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3819 continue;
3820 }
3821 start = ntohl(inet_addr(pool));
3822 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3823
3824 // Add a static route for this pool
3825 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3826 fmtaddr(htonl(start), 0), 32 + mask);
3827
3828 routeset(0, start, mask, 0, 1);
3829
3830 add_to_ip_pool(start, mask);
3831 }
3832 else
3833 {
3834 // It's a single ip address
3835 add_to_ip_pool(inet_addr(pool), 0);
3836 }
3837 }
3838 fclose(f);
3839 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3840 }
3841
3842 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3843 {
3844 struct sockaddr_in snoop_addr = {0};
3845 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3846 return;
3847
3848 snoop_addr.sin_family = AF_INET;
3849 snoop_addr.sin_addr.s_addr = destination;
3850 snoop_addr.sin_port = ntohs(port);
3851
3852 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3853 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3854 htons(snoop_addr.sin_port));
3855
3856 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3857 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3858
3859 STAT(packets_snooped);
3860 }
3861
3862 static int dump_session(FILE **f, sessiont *s)
3863 {
3864 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3865 return 1;
3866
3867 if (!*f)
3868 {
3869 char filename[1024];
3870 char timestr[64];
3871 time_t now = time(NULL);
3872
3873 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3874 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3875
3876 if (!(*f = fopen(filename, "w")))
3877 {
3878 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3879 return 0;
3880 }
3881
3882 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3883 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3884 "# host: %s\n"
3885 "# endpoint: %s\n"
3886 "# time: %ld\n"
3887 "# uptime: %ld\n"
3888 "# format: username ip qos uptxoctets downrxoctets\n",
3889 hostname,
3890 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3891 now,
3892 now - basetime);
3893 }
3894
3895 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3896 fprintf(*f, "%s %s %d %u %u\n",
3897 s->user, // username
3898 fmtaddr(htonl(s->ip), 0), // ip
3899 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3900 (uint32_t) s->cin_delta, // uptxoctets
3901 (uint32_t) s->cout_delta); // downrxoctets
3902
3903 s->cin_delta = s->cout_delta = 0;
3904
3905 return 1;
3906 }
3907
3908 static void dump_acct_info(int all)
3909 {
3910 int i;
3911 FILE *f = NULL;
3912
3913
3914 CSTAT(dump_acct_info);
3915
3916 if (shut_acct_n)
3917 {
3918 for (i = 0; i < shut_acct_n; i++)
3919 dump_session(&f, &shut_acct[i]);
3920
3921 shut_acct_n = 0;
3922 }
3923
3924 if (all)
3925 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3926 dump_session(&f, &session[i]);
3927
3928 if (f)
3929 fclose(f);
3930 }
3931
3932 // Main program
3933 int main(int argc, char *argv[])
3934 {
3935 int i;
3936 int optdebug = 0;
3937 char *optconfig = CONFIGFILE;
3938
3939 time(&basetime); // start clock
3940
3941 // scan args
3942 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3943 {
3944 switch (i)
3945 {
3946 case 'd':
3947 if (fork()) exit(0);
3948 setsid();
3949 freopen("/dev/null", "r", stdin);
3950 freopen("/dev/null", "w", stdout);
3951 freopen("/dev/null", "w", stderr);
3952 break;
3953 case 'v':
3954 optdebug++;
3955 break;
3956 case 'c':
3957 optconfig = optarg;
3958 break;
3959 case 'h':
3960 snprintf(hostname, sizeof(hostname), "%s", optarg);
3961 break;
3962 default:
3963 printf("Args are:\n"
3964 "\t-d\t\tDetach from terminal\n"
3965 "\t-c <file>\tConfig file\n"
3966 "\t-h <hostname>\tForce hostname\n"
3967 "\t-v\t\tDebug\n");
3968
3969 return (0);
3970 break;
3971 }
3972 }
3973
3974 // Start the timer routine off
3975 time(&time_now);
3976 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3977 signal(SIGALRM, sigalrm_handler);
3978 siginterrupt(SIGALRM, 0);
3979
3980 initplugins();
3981 initdata(optdebug, optconfig);
3982
3983 init_cli(hostname);
3984 read_config_file();
3985 init_tbf(config->num_tbfs);
3986
3987 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3988 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3989 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3990 {
3991 struct rlimit rlim;
3992 rlim.rlim_cur = RLIM_INFINITY;
3993 rlim.rlim_max = RLIM_INFINITY;
3994 // Remove the maximum core size
3995 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3996 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3997
3998 // Make core dumps go to /tmp
3999 chdir("/tmp");
4000 }
4001
4002 if (config->scheduler_fifo)
4003 {
4004 int ret;
4005 struct sched_param params = {0};
4006 params.sched_priority = 1;
4007
4008 if (get_nprocs() < 2)
4009 {
4010 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4011 config->scheduler_fifo = 0;
4012 }
4013 else
4014 {
4015 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4016 {
4017 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4018 }
4019 else
4020 {
4021 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4022 config->scheduler_fifo = 0;
4023 }
4024 }
4025 }
4026
4027 /* Set up the cluster communications port. */
4028 if (cluster_init() < 0)
4029 exit(1);
4030
4031 inittun();
4032 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4033
4034 initudp();
4035 initrad();
4036 initippool();
4037
4038 // seed prng
4039 {
4040 unsigned seed = time_now ^ getpid();
4041 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4042 srand(seed);
4043 }
4044
4045 signal(SIGHUP, sighup_handler);
4046 signal(SIGCHLD, sigchild_handler);
4047 signal(SIGTERM, shutdown_handler);
4048 signal(SIGINT, shutdown_handler);
4049 signal(SIGQUIT, shutdown_handler);
4050
4051 // Prevent us from getting paged out
4052 if (config->lock_pages)
4053 {
4054 if (!mlockall(MCL_CURRENT))
4055 LOG(1, 0, 0, "Locking pages into memory\n");
4056 else
4057 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4058 }
4059
4060 alarm(1);
4061
4062 // Drop privileges here
4063 if (config->target_uid > 0 && geteuid() == 0)
4064 setuid(config->target_uid);
4065
4066 mainloop();
4067
4068 /* remove plugins (so cleanup code gets run) */
4069 plugins_done();
4070
4071 // Remove the PID file if we wrote it
4072 if (config->wrote_pid && *config->pid_file == '/')
4073 unlink(config->pid_file);
4074
4075 /* kill CLI children */
4076 signal(SIGTERM, SIG_IGN);
4077 kill(0, SIGTERM);
4078 return 0;
4079 }
4080
4081 static void sighup_handler(int sig)
4082 {
4083 if (log_stream)
4084 {
4085 if (log_stream != stderr)
4086 fclose(log_stream);
4087
4088 log_stream = NULL;
4089 }
4090
4091 read_config_file();
4092 }
4093
4094 static void sigalrm_handler(int sig)
4095 {
4096 // Log current traffic stats
4097
4098 snprintf(config->bandwidth, sizeof(config->bandwidth),
4099 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4100 (udp_rx / 1024.0 / 1024.0 * 8),
4101 (eth_tx / 1024.0 / 1024.0 * 8),
4102 (eth_rx / 1024.0 / 1024.0 * 8),
4103 (udp_tx / 1024.0 / 1024.0 * 8),
4104 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4105 udp_rx_pkt, eth_rx_pkt);
4106
4107 udp_tx = udp_rx = 0;
4108 udp_rx_pkt = eth_rx_pkt = 0;
4109 eth_tx = eth_rx = 0;
4110
4111 if (config->dump_speed)
4112 printf("%s\n", config->bandwidth);
4113
4114 // Update the internal time counter
4115 time(&time_now);
4116 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4117 alarm(1);
4118
4119 {
4120 // Run timer hooks
4121 struct param_timer p = { time_now };
4122 run_plugins(PLUGIN_TIMER, &p);
4123 }
4124
4125 }
4126
4127 static void shutdown_handler(int sig)
4128 {
4129 LOG(1, 0, 0, "Shutting down\n");
4130 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4131 }
4132
4133 static void sigchild_handler(int sig)
4134 {
4135 while (waitpid(-1, NULL, WNOHANG) > 0)
4136 ;
4137 }
4138
4139 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4140 {
4141 MD5_CTX ctx;
4142 *challenge_response = NULL;
4143
4144 if (!*config->l2tpsecret)
4145 {
4146 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4147 return;
4148 }
4149
4150 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4151
4152 *challenge_response = calloc(17, 1);
4153
4154 MD5_Init(&ctx);
4155 MD5_Update(&ctx, &id, 1);
4156 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4157 MD5_Update(&ctx, challenge, challenge_length);
4158 MD5_Final(*challenge_response, &ctx);
4159
4160 return;
4161 }
4162
4163 static int facility_value(char *name)
4164 {
4165 int i;
4166 for (i = 0; facilitynames[i].c_name; i++)
4167 {
4168 if (strcmp(facilitynames[i].c_name, name) == 0)
4169 return facilitynames[i].c_val;
4170 }
4171 return 0;
4172 }
4173
4174 static void update_config()
4175 {
4176 int i;
4177 char *p;
4178 static int timeout = 0;
4179 static int interval = 0;
4180
4181 // Update logging
4182 closelog();
4183 syslog_log = 0;
4184 if (log_stream)
4185 {
4186 if (log_stream != stderr)
4187 fclose(log_stream);
4188
4189 log_stream = NULL;
4190 }
4191
4192 if (*config->log_filename)
4193 {
4194 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4195 {
4196 char *p = config->log_filename + 7;
4197 if (*p)
4198 {
4199 openlog("l2tpns", LOG_PID, facility_value(p));
4200 syslog_log = 1;
4201 }
4202 }
4203 else if (strchr(config->log_filename, '/') == config->log_filename)
4204 {
4205 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4206 {
4207 fseek(log_stream, 0, SEEK_END);
4208 setbuf(log_stream, NULL);
4209 }
4210 else
4211 {
4212 log_stream = stderr;
4213 setbuf(log_stream, NULL);
4214 }
4215 }
4216 }
4217 else
4218 {
4219 log_stream = stderr;
4220 setbuf(log_stream, NULL);
4221 }
4222
4223 // Update radius
4224 config->numradiusservers = 0;
4225 for (i = 0; i < MAXRADSERVER; i++)
4226 if (config->radiusserver[i])
4227 {
4228 config->numradiusservers++;
4229 // Set radius port: if not set, take the port from the
4230 // first radius server. For the first radius server,
4231 // take the #defined default value from l2tpns.h
4232
4233 // test twice, In case someone works with
4234 // a secondary radius server without defining
4235 // a primary one, this will work even then.
4236 if (i > 0 && !config->radiusport[i])
4237 config->radiusport[i] = config->radiusport[i-1];
4238 if (!config->radiusport[i])
4239 config->radiusport[i] = RADPORT;
4240 }
4241
4242 if (!config->numradiusservers)
4243 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4244
4245 // parse radius_authtypes_s
4246 config->radius_authtypes = config->radius_authprefer = 0;
4247 p = config->radius_authtypes_s;
4248 while (p && *p)
4249 {
4250 char *s = strpbrk(p, " \t,");
4251 int type = 0;
4252
4253 if (s)
4254 {
4255 *s++ = 0;
4256 while (*s == ' ' || *s == '\t')
4257 s++;
4258
4259 if (!*s)
4260 s = 0;
4261 }
4262
4263 if (!strncasecmp("chap", p, strlen(p)))
4264 type = AUTHCHAP;
4265 else if (!strncasecmp("pap", p, strlen(p)))
4266 type = AUTHPAP;
4267 else
4268 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4269
4270 config->radius_authtypes |= type;
4271 if (!config->radius_authprefer)
4272 config->radius_authprefer = type;
4273
4274 p = s;
4275 }
4276
4277 if (!config->radius_authtypes)
4278 {
4279 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4280 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4281 }
4282
4283 // normalise radius_authtypes_s
4284 if (config->radius_authprefer == AUTHPAP)
4285 {
4286 strcpy(config->radius_authtypes_s, "pap");
4287 if (config->radius_authtypes & AUTHCHAP)
4288 strcat(config->radius_authtypes_s, ", chap");
4289 }
4290 else
4291 {
4292 strcpy(config->radius_authtypes_s, "chap");
4293 if (config->radius_authtypes & AUTHPAP)
4294 strcat(config->radius_authtypes_s, ", pap");
4295 }
4296
4297 if (!config->radius_dae_port)
4298 config->radius_dae_port = DAEPORT;
4299
4300 // re-initialise the random number source
4301 initrandom(config->random_device);
4302
4303 // Update plugins
4304 for (i = 0; i < MAXPLUGINS; i++)
4305 {
4306 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4307 continue;
4308
4309 if (*config->plugins[i])
4310 {
4311 // Plugin added
4312 add_plugin(config->plugins[i]);
4313 }
4314 else if (*config->old_plugins[i])
4315 {
4316 // Plugin removed
4317 remove_plugin(config->old_plugins[i]);
4318 }
4319 }
4320
4321 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4322 if (!config->multi_read_count) config->multi_read_count = 10;
4323 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4324 if (!*config->cluster_interface)
4325 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4326
4327 if (!config->cluster_hb_interval)
4328 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4329
4330 if (!config->cluster_hb_timeout)
4331 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4332
4333 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4334 {
4335 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4336 // late, ensure we're sufficiently larger than that
4337 int t = 4 * config->cluster_hb_interval + 11;
4338
4339 if (config->cluster_hb_timeout < t)
4340 {
4341 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4342 config->cluster_hb_timeout = t;
4343 }
4344
4345 // Push timing changes to the slaves immediately if we're the master
4346 if (config->cluster_iam_master)
4347 cluster_heartbeat();
4348
4349 interval = config->cluster_hb_interval;
4350 timeout = config->cluster_hb_timeout;
4351 }
4352
4353 // Write PID file
4354 if (*config->pid_file == '/' && !config->wrote_pid)
4355 {
4356 FILE *f;
4357 if ((f = fopen(config->pid_file, "w")))
4358 {
4359 fprintf(f, "%d\n", getpid());
4360 fclose(f);
4361 config->wrote_pid = 1;
4362 }
4363 else
4364 {
4365 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4366 }
4367 }
4368
4369 config->reload_config = 0;
4370 }
4371
4372 static void read_config_file()
4373 {
4374 FILE *f;
4375
4376 if (!config->config_file) return;
4377 if (!(f = fopen(config->config_file, "r")))
4378 {
4379 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4380 return;
4381 }
4382
4383 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4384 cli_do_file(f);
4385 LOG(3, 0, 0, "Done reading config file\n");
4386 fclose(f);
4387 update_config();
4388 }
4389
4390 int sessionsetup(sessionidt s, tunnelidt t)
4391 {
4392 // A session now exists, set it up
4393 in_addr_t ip;
4394 char *user;
4395 sessionidt i;
4396 int r;
4397
4398 CSTAT(sessionsetup);
4399
4400 LOG(3, s, t, "Doing session setup for session\n");
4401
4402 if (!session[s].ip)
4403 {
4404 assign_ip_address(s);
4405 if (!session[s].ip)
4406 {
4407 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4408 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4409 return 0;
4410 }
4411 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4412 fmtaddr(htonl(session[s].ip), 0));
4413 }
4414
4415
4416 // Make sure this is right
4417 session[s].tunnel = t;
4418
4419 // zap old sessions with same IP and/or username
4420 // Don't kill gardened sessions - doing so leads to a DoS
4421 // from someone who doesn't need to know the password
4422 {
4423 ip = session[s].ip;
4424 user = session[s].user;
4425 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4426 {
4427 if (i == s) continue;
4428 if (!session[s].opened) continue;
4429 if (ip == session[i].ip)
4430 {
4431 sessionkill(i, "Duplicate IP address");
4432 continue;
4433 }
4434
4435 if (config->allow_duplicate_users) continue;
4436 if (session[s].walled_garden || session[i].walled_garden) continue;
4437 if (!strcasecmp(user, session[i].user))
4438 sessionkill(i, "Duplicate session for users");
4439 }
4440 }
4441
4442 {
4443 int routed = 0;
4444
4445 // Add the route for this session.
4446 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4447 {
4448 if ((session[s].ip & session[s].route[r].mask) ==
4449 (session[s].route[r].ip & session[s].route[r].mask))
4450 routed++;
4451
4452 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4453 }
4454
4455 // Static IPs need to be routed if not already
4456 // convered by a Framed-Route. Anything else is part
4457 // of the IP address pool and is already routed, it
4458 // just needs to be added to the IP cache.
4459 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4460 if (session[s].ip_pool_index == -1) // static ip
4461 {
4462 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4463 }
4464 else
4465 cache_ipmap(session[s].ip, s);
4466 }
4467
4468 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4469 lcp_open(s, t); // transition to Network phase and send initial IPCP
4470
4471 // Run the plugin's against this new session.
4472 {
4473 struct param_new_session data = { &tunnel[t], &session[s] };
4474 run_plugins(PLUGIN_NEW_SESSION, &data);
4475 }
4476
4477 // Allocate TBFs if throttled
4478 if (session[s].throttle_in || session[s].throttle_out)
4479 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4480
4481 session[s].last_packet = time_now;
4482
4483 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4484 fmtaddr(htonl(session[s].ip), 0),
4485 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4486
4487 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4488
4489 return 1; // RADIUS OK and IP allocated, done...
4490 }
4491
4492 //
4493 // This session just got dropped on us by the master or something.
4494 // Make sure our tables up up to date...
4495 //
4496 int load_session(sessionidt s, sessiont *new)
4497 {
4498 int i;
4499 int newip = 0;
4500
4501 // Sanity checks.
4502 if (new->ip_pool_index >= MAXIPPOOL ||
4503 new->tunnel >= MAXTUNNEL)
4504 {
4505 LOG(0, s, 0, "Strange session update received!\n");
4506 // FIXME! What to do here?
4507 return 0;
4508 }
4509
4510 //
4511 // Ok. All sanity checks passed. Now we're committed to
4512 // loading the new session.
4513 //
4514
4515 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4516
4517 // See if routes/ip cache need updating
4518 if (new->ip != session[s].ip)
4519 newip++;
4520
4521 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4522 if (new->route[i].ip != session[s].route[i].ip ||
4523 new->route[i].mask != session[s].route[i].mask)
4524 newip++;
4525
4526 // needs update
4527 if (newip)
4528 {
4529 int routed = 0;
4530
4531 // remove old routes...
4532 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4533 {
4534 if ((session[s].ip & session[s].route[i].mask) ==
4535 (session[s].route[i].ip & session[s].route[i].mask))
4536 routed++;
4537
4538 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4539 }
4540
4541 // ...ip
4542 if (session[s].ip)
4543 {
4544 if (session[s].ip_pool_index == -1) // static IP
4545 {
4546 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4547 }
4548 else // It's part of the IP pool, remove it manually.
4549 uncache_ipmap(session[s].ip);
4550 }
4551
4552 routed = 0;
4553
4554 // add new routes...
4555 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4556 {
4557 if ((new->ip & new->route[i].mask) ==
4558 (new->route[i].ip & new->route[i].mask))
4559 routed++;
4560
4561 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4562 }
4563
4564 // ...ip
4565 if (new->ip)
4566 {
4567 // If there's a new one, add it.
4568 if (new->ip_pool_index == -1)
4569 {
4570 if (!routed) routeset(s, new->ip, 0, 0, 1);
4571 }
4572 else
4573 cache_ipmap(new->ip, s);
4574 }
4575 }
4576
4577 // check v6 routing
4578 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4579 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4580
4581 // check filters
4582 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4583 {
4584 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4585 new->filter_in = 0;
4586 }
4587
4588 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4589 {
4590 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4591 new->filter_out = 0;
4592 }
4593
4594 if (new->filter_in != session[s].filter_in)
4595 {
4596 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4597 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4598 }
4599
4600 if (new->filter_out != session[s].filter_out)
4601 {
4602 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4603 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4604 }
4605
4606 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4607 // for walking the sessions to forward byte counts to the master.
4608 config->cluster_highest_sessionid = s;
4609
4610 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4611
4612 // Do fixups into address pool.
4613 if (new->ip_pool_index != -1)
4614 fix_address_pool(s);
4615
4616 return 1;
4617 }
4618
4619 static void initplugins()
4620 {
4621 int i;
4622
4623 loaded_plugins = ll_init();
4624 // Initialize the plugins to nothing
4625 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4626 plugins[i] = ll_init();
4627 }
4628
4629 static void *open_plugin(char *plugin_name, int load)
4630 {
4631 char path[256] = "";
4632
4633 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4634 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4635 return dlopen(path, RTLD_NOW);
4636 }
4637
4638 // plugin callback to get a config value
4639 static void *getconfig(char *key, enum config_typet type)
4640 {
4641 int i;
4642
4643 for (i = 0; config_values[i].key; i++)
4644 {
4645 if (!strcmp(config_values[i].key, key))
4646 {
4647 if (config_values[i].type == type)
4648 return ((void *) config) + config_values[i].offset;
4649
4650 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4651 key, type, config_values[i].type);
4652
4653 return 0;
4654 }
4655 }
4656
4657 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4658 return 0;
4659 }
4660
4661 static int add_plugin(char *plugin_name)
4662 {
4663 static struct pluginfuncs funcs = {
4664 _log,
4665 _log_hex,
4666 fmtaddr,
4667 sessionbyuser,
4668 sessiontbysessionidt,
4669 sessionidtbysessiont,
4670 radiusnew,
4671 radiussend,
4672 getconfig,
4673 sessionshutdown,
4674 sessionkill,
4675 throttle_session,
4676 cluster_send_session,
4677 };
4678
4679 void *p = open_plugin(plugin_name, 1);
4680 int (*initfunc)(struct pluginfuncs *);
4681 int i;
4682
4683 if (!p)
4684 {
4685 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4686 return -1;
4687 }
4688
4689 if (ll_contains(loaded_plugins, p))
4690 {
4691 dlclose(p);
4692 return 0; // already loaded
4693 }
4694
4695 {
4696 int *v = dlsym(p, "plugin_api_version");
4697 if (!v || *v != PLUGIN_API_VERSION)
4698 {
4699 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4700 dlclose(p);
4701 return -1;
4702 }
4703 }
4704
4705 if ((initfunc = dlsym(p, "plugin_init")))
4706 {
4707 if (!initfunc(&funcs))
4708 {
4709 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4710 dlclose(p);
4711 return -1;
4712 }
4713 }
4714
4715 ll_push(loaded_plugins, p);
4716
4717 for (i = 0; i < max_plugin_functions; i++)
4718 {
4719 void *x;
4720 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4721 {
4722 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4723 ll_push(plugins[i], x);
4724 }
4725 }
4726
4727 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4728 return 1;
4729 }
4730
4731 static void run_plugin_done(void *plugin)
4732 {
4733 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4734
4735 if (donefunc)
4736 donefunc();
4737 }
4738
4739 static int remove_plugin(char *plugin_name)
4740 {
4741 void *p = open_plugin(plugin_name, 0);
4742 int loaded = 0;
4743
4744 if (!p)
4745 return -1;
4746
4747 if (ll_contains(loaded_plugins, p))
4748 {
4749 int i;
4750 for (i = 0; i < max_plugin_functions; i++)
4751 {
4752 void *x;
4753 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4754 ll_delete(plugins[i], x);
4755 }
4756
4757 ll_delete(loaded_plugins, p);
4758 run_plugin_done(p);
4759 loaded = 1;
4760 }
4761
4762 dlclose(p);
4763 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4764 return loaded;
4765 }
4766
4767 int run_plugins(int plugin_type, void *data)
4768 {
4769 int (*func)(void *data);
4770
4771 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4772 return PLUGIN_RET_ERROR;
4773
4774 ll_reset(plugins[plugin_type]);
4775 while ((func = ll_next(plugins[plugin_type])))
4776 {
4777 int r = func(data);
4778
4779 if (r != PLUGIN_RET_OK)
4780 return r; // stop here
4781 }
4782
4783 return PLUGIN_RET_OK;
4784 }
4785
4786 static void plugins_done()
4787 {
4788 void *p;
4789
4790 ll_reset(loaded_plugins);
4791 while ((p = ll_next(loaded_plugins)))
4792 run_plugin_done(p);
4793 }
4794
4795 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4796 {
4797 struct nsctl request;
4798 struct nsctl response;
4799 int type = unpack_control(&request, buf, len);
4800 int r;
4801 void *p;
4802
4803 if (log_stream && config->debug >= 4)
4804 {
4805 if (type < 0)
4806 {
4807 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4808 fmtaddr(addr->sin_addr.s_addr, 0), type);
4809 }
4810 else
4811 {
4812 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4813 dump_control(&request, log_stream);
4814 }
4815 }
4816
4817 switch (type)
4818 {
4819 case NSCTL_REQ_LOAD:
4820 if (request.argc != 1)
4821 {
4822 response.type = NSCTL_RES_ERR;
4823 response.argc = 1;
4824 response.argv[0] = "name of plugin required";
4825 }
4826 else if ((r = add_plugin(request.argv[0])) < 1)
4827 {
4828 response.type = NSCTL_RES_ERR;
4829 response.argc = 1;
4830 response.argv[0] = !r
4831 ? "plugin already loaded"
4832 : "error loading plugin";
4833 }
4834 else
4835 {
4836 response.type = NSCTL_RES_OK;
4837 response.argc = 0;
4838 }
4839
4840 break;
4841
4842 case NSCTL_REQ_UNLOAD:
4843 if (request.argc != 1)
4844 {
4845 response.type = NSCTL_RES_ERR;
4846 response.argc = 1;
4847 response.argv[0] = "name of plugin required";
4848 }
4849 else if ((r = remove_plugin(request.argv[0])) < 1)
4850 {
4851 response.type = NSCTL_RES_ERR;
4852 response.argc = 1;
4853 response.argv[0] = !r
4854 ? "plugin not loaded"
4855 : "plugin not found";
4856 }
4857 else
4858 {
4859 response.type = NSCTL_RES_OK;
4860 response.argc = 0;
4861 }
4862
4863 break;
4864
4865 case NSCTL_REQ_HELP:
4866 response.type = NSCTL_RES_OK;
4867 response.argc = 0;
4868
4869 ll_reset(loaded_plugins);
4870 while ((p = ll_next(loaded_plugins)))
4871 {
4872 char **help = dlsym(p, "plugin_control_help");
4873 while (response.argc < 0xff && help && *help)
4874 response.argv[response.argc++] = *help++;
4875 }
4876
4877 break;
4878
4879 case NSCTL_REQ_CONTROL:
4880 {
4881 struct param_control param = {
4882 config->cluster_iam_master,
4883 request.argc,
4884 request.argv,
4885 0,
4886 NULL,
4887 };
4888
4889 int r = run_plugins(PLUGIN_CONTROL, &param);
4890
4891 if (r == PLUGIN_RET_ERROR)
4892 {
4893 response.type = NSCTL_RES_ERR;
4894 response.argc = 1;
4895 response.argv[0] = param.additional
4896 ? param.additional
4897 : "error returned by plugin";
4898 }
4899 else if (r == PLUGIN_RET_NOTMASTER)
4900 {
4901 static char msg[] = "must be run on master: 000.000.000.000";
4902
4903 response.type = NSCTL_RES_ERR;
4904 response.argc = 1;
4905 if (config->cluster_master_address)
4906 {
4907 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4908 response.argv[0] = msg;
4909 }
4910 else
4911 {
4912 response.argv[0] = "must be run on master: none elected";
4913 }
4914 }
4915 else if (!(param.response & NSCTL_RESPONSE))
4916 {
4917 response.type = NSCTL_RES_ERR;
4918 response.argc = 1;
4919 response.argv[0] = param.response
4920 ? "unrecognised response value from plugin"
4921 : "unhandled action";
4922 }
4923 else
4924 {
4925 response.type = param.response;
4926 response.argc = 0;
4927 if (param.additional)
4928 {
4929 response.argc = 1;
4930 response.argv[0] = param.additional;
4931 }
4932 }
4933 }
4934
4935 break;
4936
4937 default:
4938 response.type = NSCTL_RES_ERR;
4939 response.argc = 1;
4940 response.argv[0] = "error unpacking control packet";
4941 }
4942
4943 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4944 if (!buf)
4945 {
4946 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4947 return;
4948 }
4949
4950 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4951 if (r > 0)
4952 {
4953 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4954 if (log_stream && config->debug >= 4)
4955 {
4956 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4957 dump_control(&response, log_stream);
4958 }
4959 }
4960 else
4961 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4962 fmtaddr(addr->sin_addr.s_addr, 0), r);
4963
4964 free(buf);
4965 }
4966
4967 static tunnelidt new_tunnel()
4968 {
4969 tunnelidt i;
4970 for (i = 1; i < MAXTUNNEL; i++)
4971 {
4972 if (tunnel[i].state == TUNNELFREE)
4973 {
4974 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4975 if (i > config->cluster_highest_tunnelid)
4976 config->cluster_highest_tunnelid = i;
4977 return i;
4978 }
4979 }
4980 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4981 return 0;
4982 }
4983
4984 //
4985 // We're becoming the master. Do any required setup..
4986 //
4987 // This is principally telling all the plugins that we're
4988 // now a master, and telling them about all the sessions
4989 // that are active too..
4990 //
4991 void become_master(void)
4992 {
4993 int s, i;
4994 static struct event_data d[RADIUS_FDS];
4995 struct epoll_event e;
4996
4997 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4998
4999 // running a bunch of iptables commands is slow and can cause
5000 // the master to drop tunnels on takeover--kludge around the
5001 // problem by forking for the moment (note: race)
5002 if (!fork_and_close())
5003 {
5004 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5005 {
5006 if (!session[s].opened) // Not an in-use session.
5007 continue;
5008
5009 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5010 }
5011 exit(0);
5012 }
5013
5014 // add radius fds
5015 e.events = EPOLLIN;
5016 for (i = 0; i < RADIUS_FDS; i++)
5017 {
5018 d[i].type = FD_TYPE_RADIUS;
5019 d[i].index = i;
5020 e.data.ptr = &d[i];
5021
5022 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5023 }
5024 }
5025
5026 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5027 {
5028 int s, i;
5029 int count = 0;
5030 int buckets[64];
5031
5032 if (CLI_HELP_REQUESTED)
5033 return CLI_HELP_NO_ARGS;
5034
5035 time(&time_now);
5036 for (i = 0; i < 64;++i) buckets[i] = 0;
5037
5038 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5039 {
5040 int idle;
5041 if (!session[s].opened)
5042 continue;
5043
5044 idle = time_now - session[s].last_packet;
5045 idle /= 5 ; // In multiples of 5 seconds.
5046 if (idle < 0)
5047 idle = 0;
5048 if (idle > 63)
5049 idle = 63;
5050
5051 ++count;
5052 ++buckets[idle];
5053 }
5054
5055 for (i = 0; i < 63; ++i)
5056 {
5057 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5058 }
5059 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5060 cli_print(cli, "%d total sessions open.", count);
5061 return CLI_OK;
5062 }
5063
5064 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5065 {
5066 int s, i;
5067 int count = 0;
5068 int buckets[64];
5069
5070 if (CLI_HELP_REQUESTED)
5071 return CLI_HELP_NO_ARGS;
5072
5073 time(&time_now);
5074 for (i = 0; i < 64;++i) buckets[i] = 0;
5075
5076 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5077 {
5078 int open = 0, d;
5079 if (!session[s].opened)
5080 continue;
5081
5082 d = time_now - session[s].opened;
5083 if (d < 0)
5084 d = 0;
5085 while (d > 1 && open < 32)
5086 {
5087 ++open;
5088 d >>= 1; // half.
5089 }
5090 ++count;
5091 ++buckets[open];
5092 }
5093
5094 s = 1;
5095 for (i = 0; i < 30; ++i)
5096 {
5097 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5098 s <<= 1;
5099 }
5100 cli_print(cli, "%d total sessions open.", count);
5101 return CLI_OK;
5102 }
5103
5104 /* Unhide an avp.
5105 *
5106 * This unencodes the AVP using the L2TP secret and the previously
5107 * stored random vector. It overwrites the hidden data with the
5108 * unhidden AVP subformat.
5109 */
5110 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5111 {
5112 MD5_CTX ctx;
5113 uint8_t digest[16];
5114 uint8_t *last;
5115 size_t d = 0;
5116 uint16_t m = htons(type);
5117
5118 // Compute initial pad
5119 MD5_Init(&ctx);
5120 MD5_Update(&ctx, (unsigned char *) &m, 2);
5121 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5122 MD5_Update(&ctx, vector, vec_len);
5123 MD5_Final(digest, &ctx);
5124
5125 // pointer to last decoded 16 octets
5126 last = value;
5127
5128 while (len > 0)
5129 {
5130 // calculate a new pad based on the last decoded block
5131 if (d >= sizeof(digest))
5132 {
5133 MD5_Init(&ctx);
5134 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5135 MD5_Update(&ctx, last, sizeof(digest));
5136 MD5_Final(digest, &ctx);
5137
5138 d = 0;
5139 last = value;
5140 }
5141
5142 *value++ ^= digest[d++];
5143 len--;
5144 }
5145 }
5146
5147 int find_filter(char const *name, size_t len)
5148 {
5149 int free = -1;
5150 int i;
5151
5152 for (i = 0; i < MAXFILTER; i++)
5153 {
5154 if (!*ip_filters[i].name)
5155 {
5156 if (free < 0)
5157 free = i;
5158
5159 continue;
5160 }
5161
5162 if (strlen(ip_filters[i].name) != len)
5163 continue;
5164
5165 if (!strncmp(ip_filters[i].name, name, len))
5166 return i;
5167 }
5168
5169 return free;
5170 }
5171
5172 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5173 {
5174 switch (p->op)
5175 {
5176 case FILTER_PORT_OP_EQ: return port == p->port;
5177 case FILTER_PORT_OP_NEQ: return port != p->port;
5178 case FILTER_PORT_OP_GT: return port > p->port;
5179 case FILTER_PORT_OP_LT: return port < p->port;
5180 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5181 }
5182
5183 return 0;
5184 }
5185
5186 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5187 {
5188 switch (op)
5189 {
5190 case FILTER_FLAG_OP_ANY:
5191 return (flags & sflags) || (~flags & cflags);
5192
5193 case FILTER_FLAG_OP_ALL:
5194 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5195
5196 case FILTER_FLAG_OP_EST:
5197 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5198 }
5199
5200 return 0;
5201 }
5202
5203 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5204 {
5205 uint16_t frag_offset;
5206 uint8_t proto;
5207 in_addr_t src_ip;
5208 in_addr_t dst_ip;
5209 uint16_t src_port = 0;
5210 uint16_t dst_port = 0;
5211 uint8_t flags = 0;
5212 ip_filter_rulet *rule;
5213
5214 if (len < 20) // up to end of destination address
5215 return 0;
5216
5217 if ((*buf >> 4) != 4) // IPv4
5218 return 0;
5219
5220 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5221 proto = buf[9];
5222 src_ip = *(in_addr_t *) (buf + 12);
5223 dst_ip = *(in_addr_t *) (buf + 16);
5224
5225 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5226 {
5227 int l = (buf[0] & 0xf) * 4; // length of IP header
5228 if (len < l + 4) // ports
5229 return 0;
5230
5231 src_port = ntohs(*(uint16_t *) (buf + l));
5232 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5233 if (proto == IPPROTO_TCP)
5234 {
5235 if (len < l + 14) // flags
5236 return 0;
5237
5238 flags = buf[l + 13] & 0x3f;
5239 }
5240 }
5241
5242 for (rule = ip_filters[filter].rules; rule->action; rule++)
5243 {
5244 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5245 continue;
5246
5247 if (rule->src_wild != INADDR_BROADCAST &&
5248 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5249 continue;
5250
5251 if (rule->dst_wild != INADDR_BROADCAST &&
5252 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5253 continue;
5254
5255 if (frag_offset)
5256 {
5257 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5258 continue;
5259 }
5260 else
5261 {
5262 if (rule->frag)
5263 continue;
5264
5265 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5266 {
5267 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5268 continue;
5269
5270 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5271 continue;
5272
5273 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5274 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5275 continue;
5276 }
5277 }
5278
5279 // matched
5280 rule->counter++;
5281 return rule->action == FILTER_ACTION_PERMIT;
5282 }
5283
5284 // default deny
5285 return 0;
5286 }