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[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 1.131 2005-09-13 14:27:14 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_mcast_ttl", cluster_mcast_ttl, INT),
139 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
140 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
141 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
142 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
143 { NULL, 0, 0, 0 },
144 };
145
146 static char *plugin_functions[] = {
147 NULL,
148 "plugin_pre_auth",
149 "plugin_post_auth",
150 "plugin_packet_rx",
151 "plugin_packet_tx",
152 "plugin_timer",
153 "plugin_new_session",
154 "plugin_kill_session",
155 "plugin_control",
156 "plugin_radius_response",
157 "plugin_radius_reset",
158 "plugin_become_master",
159 "plugin_new_session_master",
160 };
161
162 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
163
164 // Counters for shutdown sessions
165 static sessiont shut_acct[8192];
166 static sessionidt shut_acct_n = 0;
167
168 tunnelt *tunnel = NULL; // Array of tunnel structures.
169 sessiont *session = NULL; // Array of session structures.
170 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
171 radiust *radius = NULL; // Array of radius structures.
172 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
173 ip_filtert *ip_filters = NULL; // Array of named filters.
174 static controlt *controlfree = 0;
175 struct Tstats *_statistics = NULL;
176 #ifdef RINGBUFFER
177 struct Tringbuffer *ringbuffer = NULL;
178 #endif
179
180 static void cache_ipmap(in_addr_t ip, int s);
181 static void uncache_ipmap(in_addr_t ip);
182 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
183 static void free_ip_address(sessionidt s);
184 static void dump_acct_info(int all);
185 static void sighup_handler(int sig);
186 static void sigalrm_handler(int sig);
187 static void shutdown_handler(int sig);
188 static void sigchild_handler(int sig);
189 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
190 static void update_config(void);
191 static void read_config_file(void);
192 static void initplugins(void);
193 static int add_plugin(char *plugin_name);
194 static int remove_plugin(char *plugin_name);
195 static void plugins_done(void);
196 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
197 static tunnelidt new_tunnel(void);
198 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
199
200 // on slaves, alow BGP to withdraw cleanly before exiting
201 #define QUIT_DELAY 5
202
203 // quit actions (master)
204 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
205 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
206
207 // return internal time (10ths since process startup), set f if given
208 static clockt now(double *f)
209 {
210 struct timeval t;
211 gettimeofday(&t, 0);
212 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
213 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
214 }
215
216 // work out a retry time based on try number
217 // This is a straight bounded exponential backoff.
218 // Maximum re-try time is 32 seconds. (2^5).
219 clockt backoff(uint8_t try)
220 {
221 if (try > 5) try = 5; // max backoff
222 return now(NULL) + 10 * (1 << try);
223 }
224
225
226 //
227 // Log a debug message. Typically called via the LOG macro
228 //
229 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
230 {
231 static char message[65536] = {0};
232 va_list ap;
233
234 #ifdef RINGBUFFER
235 if (ringbuffer)
236 {
237 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
238 ringbuffer->tail = 0;
239 if (ringbuffer->tail == ringbuffer->head)
240 if (++ringbuffer->head >= RINGBUFFER_SIZE)
241 ringbuffer->head = 0;
242
243 ringbuffer->buffer[ringbuffer->tail].level = level;
244 ringbuffer->buffer[ringbuffer->tail].session = s;
245 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
246 va_start(ap, format);
247 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
248 va_end(ap);
249 }
250 #endif
251
252 if (config->debug < level) return;
253
254 va_start(ap, format);
255 vsnprintf(message, sizeof(message), format, ap);
256
257 if (log_stream)
258 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
259 else if (syslog_log)
260 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
261
262 va_end(ap);
263 }
264
265 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
266 {
267 int i, j;
268 const uint8_t *d = data;
269
270 if (config->debug < level) return;
271
272 // No support for _log_hex to syslog
273 if (log_stream)
274 {
275 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
276 setvbuf(log_stream, NULL, _IOFBF, 16384);
277
278 for (i = 0; i < maxsize; )
279 {
280 fprintf(log_stream, "%4X: ", i);
281 for (j = i; j < maxsize && j < (i + 16); j++)
282 {
283 fprintf(log_stream, "%02X ", d[j]);
284 if (j == i + 7)
285 fputs(": ", log_stream);
286 }
287
288 for (; j < i + 16; j++)
289 {
290 fputs(" ", log_stream);
291 if (j == i + 7)
292 fputs(": ", log_stream);
293 }
294
295 fputs(" ", log_stream);
296 for (j = i; j < maxsize && j < (i + 16); j++)
297 {
298 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
299 fputc(d[j], log_stream);
300 else
301 fputc('.', log_stream);
302
303 if (j == i + 7)
304 fputs(" ", log_stream);
305 }
306
307 i = j;
308 fputs("\n", log_stream);
309 }
310
311 fflush(log_stream);
312 setbuf(log_stream, NULL);
313 }
314 }
315
316 // update a counter, accumulating 2^32 wraps
317 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
318 {
319 uint32_t new = *counter + delta;
320 if (new < *counter)
321 (*wrap)++;
322
323 *counter = new;
324 }
325
326 // initialise the random generator
327 static void initrandom(char *source)
328 {
329 static char path[sizeof(config->random_device)] = "*undefined*";
330
331 // reinitialise only if we are forced to do so or if the config has changed
332 if (source && !strncmp(path, source, sizeof(path)))
333 return;
334
335 // close previous source, if any
336 if (rand_fd >= 0)
337 close(rand_fd);
338
339 rand_fd = -1;
340
341 if (source)
342 {
343 // register changes
344 snprintf(path, sizeof(path), "%s", source);
345
346 if (*path == '/')
347 {
348 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
349 if (rand_fd < 0)
350 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
351 path, strerror(errno));
352 }
353 }
354 }
355
356 // fill buffer with random data
357 void random_data(uint8_t *buf, int len)
358 {
359 int n = 0;
360
361 CSTAT(random_data);
362 if (rand_fd >= 0)
363 {
364 n = read(rand_fd, buf, len);
365 if (n >= len) return;
366 if (n < 0)
367 {
368 if (errno != EAGAIN)
369 {
370 LOG(0, 0, 0, "Error reading from random source: %s\n",
371 strerror(errno));
372
373 // fall back to rand()
374 initrandom(NULL);
375 }
376
377 n = 0;
378 }
379 }
380
381 // append missing data
382 while (n < len)
383 // not using the low order bits from the prng stream
384 buf[n++] = (rand() >> 4) & 0xff;
385 }
386
387 // Add a route
388 //
389 // This adds it to the routing table, advertises it
390 // via BGP if enabled, and stuffs it into the
391 // 'sessionbyip' cache.
392 //
393 // 'ip' and 'mask' must be in _host_ order.
394 //
395 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
396 {
397 struct rtentry r;
398 int i;
399
400 if (!mask) mask = 0xffffffff;
401
402 ip &= mask; // Force the ip to be the first one in the route.
403
404 memset(&r, 0, sizeof(r));
405 r.rt_dev = config->tundevice;
406 r.rt_dst.sa_family = AF_INET;
407 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
408 r.rt_gateway.sa_family = AF_INET;
409 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
410 r.rt_genmask.sa_family = AF_INET;
411 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
412 r.rt_flags = (RTF_UP | RTF_STATIC);
413 if (gw)
414 r.rt_flags |= RTF_GATEWAY;
415 else if (mask == 0xffffffff)
416 r.rt_flags |= RTF_HOST;
417
418 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
419 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
420 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
421
422 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
423 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
424
425 #ifdef BGP
426 if (add)
427 bgp_add_route(htonl(ip), htonl(mask));
428 else
429 bgp_del_route(htonl(ip), htonl(mask));
430 #endif /* BGP */
431
432 // Add/Remove the IPs to the 'sessionbyip' cache.
433 // Note that we add the zero address in the case of
434 // a network route. Roll on CIDR.
435
436 // Note that 's == 0' implies this is the address pool.
437 // We still cache it here, because it will pre-fill
438 // the malloc'ed tree.
439
440 if (s)
441 {
442 if (!add) // Are we deleting a route?
443 s = 0; // Caching the session as '0' is the same as uncaching.
444
445 for (i = ip; (i&mask) == (ip&mask) ; ++i)
446 cache_ipmap(i, s);
447 }
448 }
449
450 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
451 {
452 struct in6_rtmsg rt;
453 char ipv6addr[INET6_ADDRSTRLEN];
454
455 if (ifr6fd < 0)
456 {
457 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
458 return;
459 }
460
461 memset(&rt, 0, sizeof(rt));
462
463 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
464 rt.rtmsg_dst_len = prefixlen;
465 rt.rtmsg_metric = 1;
466 rt.rtmsg_flags = RTF_UP;
467 rt.rtmsg_ifindex = tunidx;
468
469 LOG(1, 0, 0, "Route %s %s/%d\n",
470 add ? "add" : "del",
471 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
472 prefixlen);
473
474 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
475 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
476 strerror(errno));
477
478 // FIXME: need to add BGP routing (RFC2858)
479
480 if (s)
481 {
482 if (!add) // Are we deleting a route?
483 s = 0; // Caching the session as '0' is the same as uncaching.
484
485 cache_ipv6map(ip, prefixlen, s);
486 }
487
488 return;
489 }
490
491 // defined in linux/ipv6.h, but tricky to include from user-space
492 // TODO: move routing to use netlink rather than ioctl
493 struct in6_ifreq {
494 struct in6_addr ifr6_addr;
495 __u32 ifr6_prefixlen;
496 unsigned int ifr6_ifindex;
497 };
498
499 //
500 // Set up TUN interface
501 static void inittun(void)
502 {
503 struct ifreq ifr;
504 struct in6_ifreq ifr6;
505 struct sockaddr_in sin = {0};
506 memset(&ifr, 0, sizeof(ifr));
507 ifr.ifr_flags = IFF_TUN;
508
509 tunfd = open(TUNDEVICE, O_RDWR);
510 if (tunfd < 0)
511 { // fatal
512 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
513 exit(1);
514 }
515 {
516 int flags = fcntl(tunfd, F_GETFL, 0);
517 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
518 }
519 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
520 {
521 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
522 exit(1);
523 }
524 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
525 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
526 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
527
528 sin.sin_family = AF_INET;
529 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
530 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
531
532 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
533 {
534 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
535 exit(1);
536 }
537 /* Bump up the qlen to deal with bursts from the network */
538 ifr.ifr_qlen = 1000;
539 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
540 {
541 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
542 exit(1);
543 }
544 ifr.ifr_flags = IFF_UP;
545 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
546 {
547 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
548 exit(1);
549 }
550 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
551 {
552 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
553 exit(1);
554 }
555 tunidx = ifr.ifr_ifindex;
556
557 // Only setup IPv6 on the tun device if we have a configured prefix
558 if (config->ipv6_prefix.s6_addr[0]) {
559 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
560
561 // Link local address is FE80::1
562 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
563 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
564 ifr6.ifr6_addr.s6_addr[1] = 0x80;
565 ifr6.ifr6_addr.s6_addr[15] = 1;
566 ifr6.ifr6_prefixlen = 64;
567 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
568 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
569 {
570 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
571 " %s\n", strerror(errno));
572 }
573
574 // Global address is prefix::1
575 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
576 ifr6.ifr6_addr = config->ipv6_prefix;
577 ifr6.ifr6_addr.s6_addr[15] = 1;
578 ifr6.ifr6_prefixlen = 64;
579 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
580 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
581 {
582 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
583 strerror(errno));
584 }
585 }
586 }
587
588 // set up UDP ports
589 static void initudp(void)
590 {
591 int on = 1;
592 struct sockaddr_in addr;
593
594 // Tunnel
595 memset(&addr, 0, sizeof(addr));
596 addr.sin_family = AF_INET;
597 addr.sin_port = htons(L2TPPORT);
598 addr.sin_addr.s_addr = config->bind_address;
599 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
600 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
601 {
602 int flags = fcntl(udpfd, F_GETFL, 0);
603 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
604 }
605 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
606 {
607 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
608 exit(1);
609 }
610
611 // Control
612 memset(&addr, 0, sizeof(addr));
613 addr.sin_family = AF_INET;
614 addr.sin_port = htons(NSCTL_PORT);
615 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
616 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
617 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
618 {
619 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
620 exit(1);
621 }
622
623 // Dynamic Authorization Extensions to RADIUS
624 memset(&addr, 0, sizeof(addr));
625 addr.sin_family = AF_INET;
626 addr.sin_port = htons(config->radius_dae_port);
627 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
628 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
629 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
630 {
631 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
632 exit(1);
633 }
634
635 // Intercept
636 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
637 }
638
639 //
640 // Find session by IP, < 1 for not found
641 //
642 // Confusingly enough, this 'ip' must be
643 // in _network_ order. This being the common
644 // case when looking it up from IP packet headers.
645 //
646 // We actually use this cache for two things.
647 // #1. For used IP addresses, this maps to the
648 // session ID that it's used by.
649 // #2. For un-used IP addresses, this maps to the
650 // index into the pool table that contains that
651 // IP address.
652 //
653
654 static int lookup_ipmap(in_addr_t ip)
655 {
656 uint8_t *a = (uint8_t *) &ip;
657 uint8_t **d = (uint8_t **) ip_hash;
658
659 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
660 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
661 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
662
663 return (int) (intptr_t) d[(size_t) *a];
664 }
665
666 static int lookup_ipv6map(struct in6_addr ip)
667 {
668 struct ipv6radix *curnode;
669 int i;
670 int s;
671 char ipv6addr[INET6_ADDRSTRLEN];
672
673 curnode = &ipv6_hash[ip.s6_addr[0]];
674 i = 1;
675 s = curnode->sess;
676
677 while (s == 0 && i < 15 && curnode->branch != NULL)
678 {
679 curnode = &curnode->branch[ip.s6_addr[i]];
680 s = curnode->sess;
681 i++;
682 }
683
684 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
685 inet_ntop(AF_INET6, &ip, ipv6addr,
686 INET6_ADDRSTRLEN),
687 s);
688
689 return s;
690 }
691
692 sessionidt sessionbyip(in_addr_t ip)
693 {
694 int s = lookup_ipmap(ip);
695 CSTAT(sessionbyip);
696
697 if (s > 0 && s < MAXSESSION && session[s].opened)
698 return (sessionidt) s;
699
700 return 0;
701 }
702
703 sessionidt sessionbyipv6(struct in6_addr ip)
704 {
705 int s;
706 CSTAT(sessionbyipv6);
707
708 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
709 (ip.s6_addr[0] == 0xFE &&
710 ip.s6_addr[1] == 0x80 &&
711 ip.s6_addr16[1] == 0 &&
712 ip.s6_addr16[2] == 0 &&
713 ip.s6_addr16[3] == 0)) {
714 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
715 } else {
716 s = lookup_ipv6map(ip);
717 }
718
719 if (s > 0 && s < MAXSESSION && session[s].opened)
720 return s;
721
722 return 0;
723 }
724
725 //
726 // Take an IP address in HOST byte order and
727 // add it to the sessionid by IP cache.
728 //
729 // (It's actually cached in network order)
730 //
731 static void cache_ipmap(in_addr_t ip, int s)
732 {
733 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
734 uint8_t *a = (uint8_t *) &nip;
735 uint8_t **d = (uint8_t **) ip_hash;
736 int i;
737
738 for (i = 0; i < 3; i++)
739 {
740 if (!d[(size_t) a[i]])
741 {
742 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
743 return;
744 }
745
746 d = (uint8_t **) d[(size_t) a[i]];
747 }
748
749 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
750
751 if (s > 0)
752 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
753
754 else if (s == 0)
755 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
756 // else a map to an ip pool index.
757 }
758
759 static void uncache_ipmap(in_addr_t ip)
760 {
761 cache_ipmap(ip, 0); // Assign it to the NULL session.
762 }
763
764 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
765 {
766 int i;
767 int bytes;
768 struct ipv6radix *curnode;
769 char ipv6addr[INET6_ADDRSTRLEN];
770
771 curnode = &ipv6_hash[ip.s6_addr[0]];
772
773 bytes = prefixlen >> 3;
774 i = 1;
775 while (i < bytes) {
776 if (curnode->branch == NULL)
777 {
778 if (!(curnode->branch = calloc(256,
779 sizeof (struct ipv6radix))))
780 return;
781 }
782 curnode = &curnode->branch[ip.s6_addr[i]];
783 i++;
784 }
785
786 curnode->sess = s;
787
788 if (s > 0)
789 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
790 inet_ntop(AF_INET6, &ip, ipv6addr,
791 INET6_ADDRSTRLEN),
792 prefixlen);
793 else if (s == 0)
794 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
795 inet_ntop(AF_INET6, &ip, ipv6addr,
796 INET6_ADDRSTRLEN),
797 prefixlen);
798 }
799
800 //
801 // CLI list to dump current ipcache.
802 //
803 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
804 {
805 char **d = (char **) ip_hash, **e, **f, **g;
806 int i, j, k, l;
807 int count = 0;
808
809 if (CLI_HELP_REQUESTED)
810 return CLI_HELP_NO_ARGS;
811
812 cli_print(cli, "%7s %s", "Sess#", "IP Address");
813
814 for (i = 0; i < 256; ++i)
815 {
816 if (!d[i])
817 continue;
818 e = (char **) d[i];
819 for (j = 0; j < 256; ++j)
820 {
821 if (!e[j])
822 continue;
823 f = (char **) e[j];
824 for (k = 0; k < 256; ++k)
825 {
826 if (!f[k])
827 continue;
828 g = (char **)f[k];
829 for (l = 0; l < 256; ++l)
830 {
831 if (!g[l])
832 continue;
833 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
834 ++count;
835 }
836 }
837 }
838 }
839 cli_print(cli, "%d entries in cache", count);
840 return CLI_OK;
841 }
842
843
844 // Find session by username, 0 for not found
845 // walled garden users aren't authenticated, so the username is
846 // reasonably useless. Ignore them to avoid incorrect actions
847 //
848 // This is VERY inefficent. Don't call it often. :)
849 //
850 sessionidt sessionbyuser(char *username)
851 {
852 int s;
853 CSTAT(sessionbyuser);
854
855 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
856 {
857 if (!session[s].opened)
858 continue;
859
860 if (session[s].walled_garden)
861 continue; // Skip walled garden users.
862
863 if (!strncmp(session[s].user, username, 128))
864 return s;
865
866 }
867 return 0; // Not found.
868 }
869
870 void send_garp(in_addr_t ip)
871 {
872 int s;
873 struct ifreq ifr;
874 uint8_t mac[6];
875
876 s = socket(PF_INET, SOCK_DGRAM, 0);
877 if (s < 0)
878 {
879 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
880 return;
881 }
882 memset(&ifr, 0, sizeof(ifr));
883 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
884 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
885 {
886 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
887 close(s);
888 return;
889 }
890 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
891 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
892 {
893 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
894 close(s);
895 return;
896 }
897 close(s);
898 sendarp(ifr.ifr_ifindex, mac, ip);
899 }
900
901 static sessiont *sessiontbysessionidt(sessionidt s)
902 {
903 if (!s || s >= MAXSESSION) return NULL;
904 return &session[s];
905 }
906
907 static sessionidt sessionidtbysessiont(sessiont *s)
908 {
909 sessionidt val = s-session;
910 if (s < session || val >= MAXSESSION) return 0;
911 return val;
912 }
913
914 // actually send a control message for a specific tunnel
915 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
916 {
917 struct sockaddr_in addr;
918
919 CSTAT(tunnelsend);
920
921 if (!t)
922 {
923 static int backtrace_count = 0;
924 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
925 STAT(tunnel_tx_errors);
926 log_backtrace(backtrace_count, 5)
927 return;
928 }
929
930 if (!tunnel[t].ip)
931 {
932 static int backtrace_count = 0;
933 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
934 log_backtrace(backtrace_count, 5)
935 STAT(tunnel_tx_errors);
936 return;
937 }
938
939 memset(&addr, 0, sizeof(addr));
940 addr.sin_family = AF_INET;
941 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
942 addr.sin_port = htons(tunnel[t].port);
943
944 // sequence expected, if sequence in message
945 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
946
947 // If this is a control message, deal with retries
948 if (*buf & 0x80)
949 {
950 tunnel[t].last = time_now; // control message sent
951 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
952 if (tunnel[t].try > 1)
953 {
954 STAT(tunnel_retries);
955 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
956 }
957 }
958
959 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
960 {
961 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
962 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
963 STAT(tunnel_tx_errors);
964 return;
965 }
966
967 LOG_HEX(5, "Send Tunnel Data", buf, l);
968 STAT(tunnel_tx_packets);
969 INC_STAT(tunnel_tx_bytes, l);
970 }
971
972 //
973 // Tiny helper function to write data to
974 // the 'tun' device.
975 //
976 int tun_write(uint8_t * data, int size)
977 {
978 return write(tunfd, data, size);
979 }
980
981 // process outgoing (to tunnel) IP
982 //
983 static void processipout(uint8_t *buf, int len)
984 {
985 sessionidt s;
986 sessiont *sp;
987 tunnelidt t;
988 in_addr_t ip;
989
990 uint8_t *data = buf; // Keep a copy of the originals.
991 int size = len;
992
993 uint8_t b[MAXETHER + 20];
994
995 CSTAT(processipout);
996
997 if (len < MIN_IP_SIZE)
998 {
999 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1000 STAT(tun_rx_errors);
1001 return;
1002 }
1003 if (len >= MAXETHER)
1004 {
1005 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1006 STAT(tun_rx_errors);
1007 return;
1008 }
1009
1010 // Skip the tun header
1011 buf += 4;
1012 len -= 4;
1013
1014 // Got an IP header now
1015 if (*(uint8_t *)(buf) >> 4 != 4)
1016 {
1017 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1018 return;
1019 }
1020
1021 ip = *(uint32_t *)(buf + 16);
1022 if (!(s = sessionbyip(ip)))
1023 {
1024 // Is this a packet for a session that doesn't exist?
1025 static int rate = 0; // Number of ICMP packets we've sent this second.
1026 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1027
1028 if (last != time_now)
1029 {
1030 last = time_now;
1031 rate = 0;
1032 }
1033
1034 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1035 {
1036 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1037 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1038 config->bind_address ? config->bind_address : my_address, buf, len);
1039 }
1040 return;
1041 }
1042 t = session[s].tunnel;
1043 sp = &session[s];
1044
1045 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1046 if (config->max_packets > 0)
1047 {
1048 if (sess_local[s].last_packet_out == TIME)
1049 {
1050 int max = config->max_packets;
1051
1052 // All packets for throttled sessions are handled by the
1053 // master, so further limit by using the throttle rate.
1054 // A bit of a kludge, since throttle rate is in kbps,
1055 // but should still be generous given our average DSL
1056 // packet size is 200 bytes: a limit of 28kbps equates
1057 // to around 180 packets per second.
1058 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1059 max = sp->throttle_out;
1060
1061 if (++sess_local[s].packets_out > max)
1062 {
1063 sess_local[s].packets_dropped++;
1064 return;
1065 }
1066 }
1067 else
1068 {
1069 if (sess_local[s].packets_dropped)
1070 {
1071 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1072 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1073 sess_local[s].packets_dropped, sess_local[s].packets_out,
1074 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1075 sp->user);
1076 }
1077
1078 sess_local[s].last_packet_out = TIME;
1079 sess_local[s].packets_out = 1;
1080 sess_local[s].packets_dropped = 0;
1081 }
1082 }
1083
1084 // run access-list if any
1085 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1086 return;
1087
1088 if (sp->tbf_out)
1089 {
1090 // Are we throttling this session?
1091 if (config->cluster_iam_master)
1092 tbf_queue_packet(sp->tbf_out, data, size);
1093 else
1094 master_throttle_packet(sp->tbf_out, data, size);
1095 return;
1096 }
1097 else if (sp->walled_garden && !config->cluster_iam_master)
1098 {
1099 // We are walled-gardening this
1100 master_garden_packet(s, data, size);
1101 return;
1102 }
1103
1104 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1105
1106 // Add on L2TP header
1107 {
1108 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1109 if (!p) return;
1110 tunnelsend(b, len + (p-b), t); // send it...
1111 }
1112
1113 // Snooping this session, send it to intercept box
1114 if (sp->snoop_ip && sp->snoop_port)
1115 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1116
1117 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1118 sp->cout_delta += len;
1119 sp->pout++;
1120 udp_tx += len;
1121
1122 sess_local[s].cout += len; // To send to master..
1123 sess_local[s].pout++;
1124 }
1125
1126 // process outgoing (to tunnel) IPv6
1127 //
1128 static void processipv6out(uint8_t * buf, int len)
1129 {
1130 sessionidt s;
1131 sessiont *sp;
1132 tunnelidt t;
1133 in_addr_t ip;
1134 struct in6_addr ip6;
1135
1136 uint8_t *data = buf; // Keep a copy of the originals.
1137 int size = len;
1138
1139 uint8_t b[MAXETHER + 20];
1140
1141 CSTAT(processipv6out);
1142
1143 if (len < MIN_IP_SIZE)
1144 {
1145 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1146 STAT(tunnel_tx_errors);
1147 return;
1148 }
1149 if (len >= MAXETHER)
1150 {
1151 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1152 STAT(tunnel_tx_errors);
1153 return;
1154 }
1155
1156 // Skip the tun header
1157 buf += 4;
1158 len -= 4;
1159
1160 // Got an IP header now
1161 if (*(uint8_t *)(buf) >> 4 != 6)
1162 {
1163 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1164 return;
1165 }
1166
1167 ip6 = *(struct in6_addr *)(buf+24);
1168 s = sessionbyipv6(ip6);
1169
1170 if (s == 0)
1171 {
1172 ip = *(uint32_t *)(buf + 32);
1173 s = sessionbyip(ip);
1174 }
1175
1176 if (s == 0)
1177 {
1178 // Is this a packet for a session that doesn't exist?
1179 static int rate = 0; // Number of ICMP packets we've sent this second.
1180 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1181
1182 if (last != time_now)
1183 {
1184 last = time_now;
1185 rate = 0;
1186 }
1187
1188 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1189 {
1190 // FIXME: Should send icmp6 host unreachable
1191 }
1192 return;
1193 }
1194 t = session[s].tunnel;
1195 sp = &session[s];
1196
1197 // FIXME: add DoS prevention/filters?
1198
1199 if (sp->tbf_out)
1200 {
1201 // Are we throttling this session?
1202 if (config->cluster_iam_master)
1203 tbf_queue_packet(sp->tbf_out, data, size);
1204 else
1205 master_throttle_packet(sp->tbf_out, data, size);
1206 return;
1207 }
1208 else if (sp->walled_garden && !config->cluster_iam_master)
1209 {
1210 // We are walled-gardening this
1211 master_garden_packet(s, data, size);
1212 return;
1213 }
1214
1215 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1216
1217 // Add on L2TP header
1218 {
1219 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1220 if (!p) return;
1221 tunnelsend(b, len + (p-b), t); // send it...
1222 }
1223
1224 // Snooping this session, send it to intercept box
1225 if (sp->snoop_ip && sp->snoop_port)
1226 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1227
1228 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1229 sp->cout_delta += len;
1230 sp->pout++;
1231 udp_tx += len;
1232
1233 sess_local[s].cout += len; // To send to master..
1234 sess_local[s].pout++;
1235 }
1236
1237 //
1238 // Helper routine for the TBF filters.
1239 // Used to send queued data in to the user!
1240 //
1241 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1242 {
1243 sessiont *sp;
1244 tunnelidt t;
1245 in_addr_t ip;
1246
1247 uint8_t b[MAXETHER + 20];
1248
1249 if (len < 0 || len > MAXETHER)
1250 {
1251 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1252 return;
1253 }
1254
1255 // Skip the tun header
1256 buf += 4;
1257 len -= 4;
1258
1259 ip = *(in_addr_t *)(buf + 16);
1260
1261 if (!session[s].ip)
1262 return;
1263
1264 t = session[s].tunnel;
1265 sp = &session[s];
1266
1267 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1268
1269 // Add on L2TP header
1270 {
1271 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1272 if (!p) return;
1273 tunnelsend(b, len + (p-b), t); // send it...
1274 }
1275
1276 // Snooping this session.
1277 if (sp->snoop_ip && sp->snoop_port)
1278 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1279
1280 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1281 sp->cout_delta += len;
1282 sp->pout++;
1283 udp_tx += len;
1284
1285 sess_local[s].cout += len; // To send to master..
1286 sess_local[s].pout++;
1287 }
1288
1289 // add an AVP (16 bit)
1290 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1291 {
1292 uint16_t l = (m ? 0x8008 : 0x0008);
1293 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1294 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1295 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1296 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1297 c->length += 8;
1298 }
1299
1300 // add an AVP (32 bit)
1301 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1302 {
1303 uint16_t l = (m ? 0x800A : 0x000A);
1304 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1305 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1306 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1307 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1308 c->length += 10;
1309 }
1310
1311 // add an AVP (string)
1312 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1313 {
1314 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1315 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1316 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1317 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1318 memcpy(c->buf + c->length + 6, val, strlen(val));
1319 c->length += 6 + strlen(val);
1320 }
1321
1322 // add a binary AVP
1323 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1324 {
1325 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1326 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1327 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1328 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1329 memcpy(c->buf + c->length + 6, val, len);
1330 c->length += 6 + len;
1331 }
1332
1333 // new control connection
1334 static controlt *controlnew(uint16_t mtype)
1335 {
1336 controlt *c;
1337 if (!controlfree)
1338 c = malloc(sizeof(controlt));
1339 else
1340 {
1341 c = controlfree;
1342 controlfree = c->next;
1343 }
1344 assert(c);
1345 c->next = 0;
1346 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1347 c->length = 12;
1348 control16(c, 0, mtype, 1);
1349 return c;
1350 }
1351
1352 // send zero block if nothing is waiting
1353 // (ZLB send).
1354 static void controlnull(tunnelidt t)
1355 {
1356 uint8_t buf[12];
1357 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1358 return;
1359
1360 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1361 *(uint16_t *) (buf + 2) = htons(12); // length
1362 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1363 *(uint16_t *) (buf + 6) = htons(0); // session
1364 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1365 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1366 tunnelsend(buf, 12, t);
1367 }
1368
1369 // add a control message to a tunnel, and send if within window
1370 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1371 {
1372 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1373 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1374 *(uint16_t *) (c->buf + 6) = htons(far); // session
1375 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1376 tunnel[t].ns++; // advance sequence
1377 // link in message in to queue
1378 if (tunnel[t].controlc)
1379 tunnel[t].controle->next = c;
1380 else
1381 tunnel[t].controls = c;
1382
1383 tunnel[t].controle = c;
1384 tunnel[t].controlc++;
1385
1386 // send now if space in window
1387 if (tunnel[t].controlc <= tunnel[t].window)
1388 {
1389 tunnel[t].try = 0; // first send
1390 tunnelsend(c->buf, c->length, t);
1391 }
1392 }
1393
1394 //
1395 // Throttle or Unthrottle a session
1396 //
1397 // Throttle the data from/to through a session to no more than
1398 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1399 // user).
1400 //
1401 // If either value is -1, the current value is retained for that
1402 // direction.
1403 //
1404 void throttle_session(sessionidt s, int rate_in, int rate_out)
1405 {
1406 if (!session[s].opened)
1407 return; // No-one home.
1408
1409 if (!*session[s].user)
1410 return; // User not logged in
1411
1412 if (rate_in >= 0)
1413 {
1414 int bytes = rate_in * 1024 / 8; // kbits to bytes
1415 if (session[s].tbf_in)
1416 free_tbf(session[s].tbf_in);
1417
1418 if (rate_in > 0)
1419 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1420 else
1421 session[s].tbf_in = 0;
1422
1423 session[s].throttle_in = rate_in;
1424 }
1425
1426 if (rate_out >= 0)
1427 {
1428 int bytes = rate_out * 1024 / 8;
1429 if (session[s].tbf_out)
1430 free_tbf(session[s].tbf_out);
1431
1432 if (rate_out > 0)
1433 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1434 else
1435 session[s].tbf_out = 0;
1436
1437 session[s].throttle_out = rate_out;
1438 }
1439 }
1440
1441 // add/remove filters from session (-1 = no change)
1442 void filter_session(sessionidt s, int filter_in, int filter_out)
1443 {
1444 if (!session[s].opened)
1445 return; // No-one home.
1446
1447 if (!*session[s].user)
1448 return; // User not logged in
1449
1450 // paranoia
1451 if (filter_in > MAXFILTER) filter_in = -1;
1452 if (filter_out > MAXFILTER) filter_out = -1;
1453 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1454 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1455
1456 if (filter_in >= 0)
1457 {
1458 if (session[s].filter_in)
1459 ip_filters[session[s].filter_in - 1].used--;
1460
1461 if (filter_in > 0)
1462 ip_filters[filter_in - 1].used++;
1463
1464 session[s].filter_in = filter_in;
1465 }
1466
1467 if (filter_out >= 0)
1468 {
1469 if (session[s].filter_out)
1470 ip_filters[session[s].filter_out - 1].used--;
1471
1472 if (filter_out > 0)
1473 ip_filters[filter_out - 1].used++;
1474
1475 session[s].filter_out = filter_out;
1476 }
1477 }
1478
1479 // start tidy shutdown of session
1480 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1481 {
1482 int walled_garden = session[s].walled_garden;
1483
1484
1485 CSTAT(sessionshutdown);
1486
1487 if (!session[s].opened)
1488 {
1489 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1490 return; // not a live session
1491 }
1492
1493 if (!session[s].die)
1494 {
1495 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1496 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1497 run_plugins(PLUGIN_KILL_SESSION, &data);
1498 }
1499
1500 if (session[s].ip && !walled_garden && !session[s].die)
1501 {
1502 // RADIUS Stop message
1503 uint16_t r = radiusnew(s);
1504 if (r)
1505 {
1506 // stop, if not already trying
1507 if (radius[r].state != RADIUSSTOP)
1508 radiussend(r, RADIUSSTOP);
1509 }
1510 else
1511 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1512
1513 // Save counters to dump to accounting file
1514 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1515 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1516 }
1517
1518 if (session[s].ip)
1519 { // IP allocated, clear and unroute
1520 int r;
1521 int routed = 0;
1522 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1523 {
1524 if ((session[s].ip & session[s].route[r].mask) ==
1525 (session[s].route[r].ip & session[s].route[r].mask))
1526 routed++;
1527
1528 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1529 session[s].route[r].ip = 0;
1530 }
1531
1532 if (session[s].ip_pool_index == -1) // static ip
1533 {
1534 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1535 session[s].ip = 0;
1536 }
1537 else
1538 free_ip_address(s);
1539
1540 // unroute IPv6, if setup
1541 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1542 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1543 }
1544
1545 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1546 throttle_session(s, 0, 0);
1547
1548 if (result)
1549 { // Send CDN
1550 controlt *c = controlnew(14); // sending CDN
1551 if (error)
1552 {
1553 uint8_t buf[4];
1554 *(uint16_t *) buf = htons(result);
1555 *(uint16_t *) (buf+2) = htons(error);
1556 controlb(c, 1, buf, 4, 1);
1557 }
1558 else
1559 control16(c, 1, result, 1);
1560
1561 control16(c, 14, s, 1); // assigned session (our end)
1562 controladd(c, session[s].far, session[s].tunnel); // send the message
1563 }
1564
1565 if (!session[s].die)
1566 session[s].die = TIME + 150; // Clean up in 15 seconds
1567
1568 // update filter refcounts
1569 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1570 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1571
1572 // clear PPP state
1573 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1574 sess_local[s].lcp.restart = 0;
1575 sess_local[s].ipcp.restart = 0;
1576 sess_local[s].ipv6cp.restart = 0;
1577 sess_local[s].ccp.restart = 0;
1578
1579 cluster_send_session(s);
1580 }
1581
1582 void sendipcp(sessionidt s, tunnelidt t)
1583 {
1584 uint8_t buf[MAXETHER];
1585 uint8_t *q;
1586
1587 CSTAT(sendipcp);
1588 LOG(3, s, t, "IPCP: send ConfigReq\n");
1589
1590 if (!session[s].unique_id)
1591 {
1592 if (!++last_id) ++last_id; // skip zero
1593 session[s].unique_id = last_id;
1594 }
1595
1596 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP);
1597 if (!q) return;
1598
1599 *q = ConfigReq;
1600 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1601 *(uint16_t *) (q + 2) = htons(10); // packet length
1602 q[4] = 3; // ip address option
1603 q[5] = 6; // option length
1604 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1605 config->bind_address ? config->bind_address :
1606 my_address; // send my IP
1607
1608 tunnelsend(buf, 10 + (q - buf), t); // send it
1609 }
1610
1611 void sendipv6cp(sessionidt s, tunnelidt t)
1612 {
1613 uint8_t buf[MAXETHER];
1614 uint8_t *q;
1615
1616 CSTAT(sendipv6cp);
1617 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1618
1619 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1620 if (!q) return;
1621
1622 *q = ConfigReq;
1623 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1624 // only send one type
1625 // of request
1626 *(uint16_t *) (q + 2) = htons(14);
1627 q[4] = 1; // interface identifier option
1628 q[5] = 10; // option length
1629 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1630 *(uint32_t *) (q + 10) = 0;
1631 q[13] = 1;
1632
1633 tunnelsend(buf, 14 + (q - buf), t); // send it
1634 }
1635
1636 static void sessionclear(sessionidt s)
1637 {
1638 memset(&session[s], 0, sizeof(session[s]));
1639 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1640 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1641
1642 session[s].tunnel = T_FREE; // Mark it as free.
1643 session[s].next = sessionfree;
1644 sessionfree = s;
1645 }
1646
1647 // kill a session now
1648 void sessionkill(sessionidt s, char *reason)
1649 {
1650
1651 CSTAT(sessionkill);
1652
1653 if (!session[s].opened) // not alive
1654 return;
1655
1656 if (session[s].next)
1657 {
1658 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1659 return;
1660 }
1661
1662 session[s].die = TIME;
1663 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1664 if (sess_local[s].radius)
1665 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1666
1667 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1668 sessionclear(s);
1669 cluster_send_session(s);
1670 }
1671
1672 static void tunnelclear(tunnelidt t)
1673 {
1674 if (!t) return;
1675 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1676 tunnel[t].state = TUNNELFREE;
1677 }
1678
1679 // kill a tunnel now
1680 static void tunnelkill(tunnelidt t, char *reason)
1681 {
1682 sessionidt s;
1683 controlt *c;
1684
1685 CSTAT(tunnelkill);
1686
1687 tunnel[t].state = TUNNELDIE;
1688
1689 // free control messages
1690 while ((c = tunnel[t].controls))
1691 {
1692 controlt * n = c->next;
1693 tunnel[t].controls = n;
1694 tunnel[t].controlc--;
1695 c->next = controlfree;
1696 controlfree = c;
1697 }
1698 // kill sessions
1699 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1700 if (session[s].tunnel == t)
1701 sessionkill(s, reason);
1702
1703 // free tunnel
1704 tunnelclear(t);
1705 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1706 cli_tunnel_actions[t].action = 0;
1707 cluster_send_tunnel(t);
1708 }
1709
1710 // shut down a tunnel cleanly
1711 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1712 {
1713 sessionidt s;
1714
1715 CSTAT(tunnelshutdown);
1716
1717 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1718 {
1719 // never set up, can immediately kill
1720 tunnelkill(t, reason);
1721 return;
1722 }
1723 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1724
1725 // close session
1726 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1727 if (session[s].tunnel == t)
1728 sessionshutdown(s, reason, 0, 0);
1729
1730 tunnel[t].state = TUNNELDIE;
1731 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1732 cluster_send_tunnel(t);
1733 // TBA - should we wait for sessions to stop?
1734 if (result)
1735 {
1736 controlt *c = controlnew(4); // sending StopCCN
1737 if (error)
1738 {
1739 uint8_t buf[64];
1740 int l = 4;
1741 *(uint16_t *) buf = htons(result);
1742 *(uint16_t *) (buf+2) = htons(error);
1743 if (msg)
1744 {
1745 int m = strlen(msg);
1746 if (m + 4 > sizeof(buf))
1747 m = sizeof(buf) - 4;
1748
1749 memcpy(buf+4, msg, m);
1750 l += m;
1751 }
1752
1753 controlb(c, 1, buf, l, 1);
1754 }
1755 else
1756 control16(c, 1, result, 1);
1757
1758 control16(c, 9, t, 1); // assigned tunnel (our end)
1759 controladd(c, 0, t); // send the message
1760 }
1761 }
1762
1763 // read and process packet on tunnel (UDP)
1764 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1765 {
1766 uint8_t *chapresponse = NULL;
1767 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1768 uint8_t *p = buf + 2;
1769
1770
1771 CSTAT(processudp);
1772
1773 udp_rx += len;
1774 udp_rx_pkt++;
1775 LOG_HEX(5, "UDP Data", buf, len);
1776 STAT(tunnel_rx_packets);
1777 INC_STAT(tunnel_rx_bytes, len);
1778 if (len < 6)
1779 {
1780 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1781 STAT(tunnel_rx_errors);
1782 return;
1783 }
1784 if ((buf[1] & 0x0F) != 2)
1785 {
1786 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1787 STAT(tunnel_rx_errors);
1788 return;
1789 }
1790 if (*buf & 0x40)
1791 { // length
1792 l = ntohs(*(uint16_t *) p);
1793 p += 2;
1794 }
1795 t = ntohs(*(uint16_t *) p);
1796 p += 2;
1797 s = ntohs(*(uint16_t *) p);
1798 p += 2;
1799 if (s >= MAXSESSION)
1800 {
1801 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1802 STAT(tunnel_rx_errors);
1803 return;
1804 }
1805 if (t >= MAXTUNNEL)
1806 {
1807 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1808 STAT(tunnel_rx_errors);
1809 return;
1810 }
1811 if (*buf & 0x08)
1812 { // ns/nr
1813 ns = ntohs(*(uint16_t *) p);
1814 p += 2;
1815 nr = ntohs(*(uint16_t *) p);
1816 p += 2;
1817 }
1818 if (*buf & 0x02)
1819 { // offset
1820 uint16_t o = ntohs(*(uint16_t *) p);
1821 p += o + 2;
1822 }
1823 if ((p - buf) > l)
1824 {
1825 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1826 STAT(tunnel_rx_errors);
1827 return;
1828 }
1829 l -= (p - buf);
1830
1831 // used to time out old tunnels
1832 if (t && tunnel[t].state == TUNNELOPEN)
1833 tunnel[t].lastrec = time_now;
1834
1835 if (*buf & 0x80)
1836 { // control
1837 uint16_t message = 0xFFFF; // message type
1838 uint8_t fatal = 0;
1839 uint8_t mandatory = 0;
1840 uint16_t asession = 0; // assigned session
1841 uint32_t amagic = 0; // magic number
1842 uint8_t aflags = 0; // flags from last LCF
1843 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1844 char called[MAXTEL] = ""; // called number
1845 char calling[MAXTEL] = ""; // calling number
1846
1847 if (!config->cluster_iam_master)
1848 {
1849 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1850 return;
1851 }
1852
1853 // control messages must have bits 0x80|0x40|0x08
1854 // (type, length and sequence) set, and bits 0x02|0x01
1855 // (offset and priority) clear
1856 if ((*buf & 0xCB) != 0xC8)
1857 {
1858 LOG(1, s, t, "Bad control header %02X\n", *buf);
1859 STAT(tunnel_rx_errors);
1860 return;
1861 }
1862
1863 // check for duplicate tunnel open message
1864 if (!t && ns == 0)
1865 {
1866 int i;
1867
1868 //
1869 // Is this a duplicate of the first packet? (SCCRQ)
1870 //
1871 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1872 {
1873 if (tunnel[i].state != TUNNELOPENING ||
1874 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1875 tunnel[i].port != ntohs(addr->sin_port) )
1876 continue;
1877 t = i;
1878 LOG(3, s, t, "Duplicate SCCRQ?\n");
1879 break;
1880 }
1881 }
1882
1883 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1884 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1885
1886 // if no tunnel specified, assign one
1887 if (!t)
1888 {
1889 if (!(t = new_tunnel()))
1890 {
1891 LOG(1, 0, 0, "No more tunnels\n");
1892 STAT(tunnel_overflow);
1893 return;
1894 }
1895 tunnelclear(t);
1896 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1897 tunnel[t].port = ntohs(addr->sin_port);
1898 tunnel[t].window = 4; // default window
1899 STAT(tunnel_created);
1900 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1901 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1902 }
1903
1904 // If the 'ns' just received is not the 'nr' we're
1905 // expecting, just send an ack and drop it.
1906 //
1907 // if 'ns' is less, then we got a retransmitted packet.
1908 // if 'ns' is greater than missed a packet. Either way
1909 // we should ignore it.
1910 if (ns != tunnel[t].nr)
1911 {
1912 // is this the sequence we were expecting?
1913 STAT(tunnel_rx_errors);
1914 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1915 t, ns, tunnel[t].nr);
1916
1917 if (l) // Is this not a ZLB?
1918 controlnull(t);
1919 return;
1920 }
1921
1922 // check sequence of this message
1923 {
1924 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1925 // some to clear maybe?
1926 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1927 {
1928 controlt *c = tunnel[t].controls;
1929 tunnel[t].controls = c->next;
1930 tunnel[t].controlc--;
1931 c->next = controlfree;
1932 controlfree = c;
1933 skip--;
1934 tunnel[t].try = 0; // we have progress
1935 }
1936
1937 // receiver advance (do here so quoted correctly in any sends below)
1938 if (l) tunnel[t].nr = (ns + 1);
1939 if (skip < 0) skip = 0;
1940 if (skip < tunnel[t].controlc)
1941 {
1942 // some control packets can now be sent that were previous stuck out of window
1943 int tosend = tunnel[t].window - skip;
1944 controlt *c = tunnel[t].controls;
1945 while (c && skip)
1946 {
1947 c = c->next;
1948 skip--;
1949 }
1950 while (c && tosend)
1951 {
1952 tunnel[t].try = 0; // first send
1953 tunnelsend(c->buf, c->length, t);
1954 c = c->next;
1955 tosend--;
1956 }
1957 }
1958 if (!tunnel[t].controlc)
1959 tunnel[t].retry = 0; // caught up
1960 }
1961 if (l)
1962 { // if not a null message
1963 int result = 0;
1964 int error = 0;
1965 char *msg = 0;
1966
1967 // process AVPs
1968 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1969 {
1970 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1971 uint8_t *b = p;
1972 uint8_t flags = *p;
1973 uint16_t mtype;
1974 if (n > l)
1975 {
1976 LOG(1, s, t, "Invalid length in AVP\n");
1977 STAT(tunnel_rx_errors);
1978 return;
1979 }
1980 p += n; // next
1981 l -= n;
1982 if (flags & 0x3C) // reserved bits, should be clear
1983 {
1984 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1985 fatal = flags;
1986 result = 2; // general error
1987 error = 3; // reserved field non-zero
1988 msg = 0;
1989 continue; // next
1990 }
1991 b += 2;
1992 if (*(uint16_t *) (b))
1993 {
1994 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1995 fatal = flags;
1996 result = 2; // general error
1997 error = 6; // generic vendor-specific error
1998 msg = "unsupported vendor-specific";
1999 continue; // next
2000 }
2001 b += 2;
2002 mtype = ntohs(*(uint16_t *) (b));
2003 b += 2;
2004 n -= 6;
2005
2006 if (flags & 0x40)
2007 {
2008 uint16_t orig_len;
2009
2010 // handle hidden AVPs
2011 if (!*config->l2tpsecret)
2012 {
2013 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2014 fatal = flags;
2015 result = 2; // general error
2016 error = 6; // generic vendor-specific error
2017 msg = "secret not specified";
2018 continue;
2019 }
2020 if (!session[s].random_vector_length)
2021 {
2022 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2023 fatal = flags;
2024 result = 2; // general error
2025 error = 6; // generic
2026 msg = "no random vector";
2027 continue;
2028 }
2029 if (n < 8)
2030 {
2031 LOG(2, s, t, "Short hidden AVP.\n");
2032 fatal = flags;
2033 result = 2; // general error
2034 error = 2; // length is wrong
2035 msg = 0;
2036 continue;
2037 }
2038
2039 // Unhide the AVP
2040 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2041
2042 orig_len = ntohs(*(uint16_t *) b);
2043 if (orig_len > n + 2)
2044 {
2045 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2046 orig_len, n);
2047
2048 fatal = flags;
2049 result = 2; // general error
2050 error = 2; // length is wrong
2051 msg = 0;
2052 continue;
2053 }
2054
2055 b += 2;
2056 n = orig_len;
2057 }
2058
2059 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2060 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2061
2062 switch (mtype)
2063 {
2064 case 0: // message type
2065 message = ntohs(*(uint16_t *) b);
2066 mandatory = flags & 0x80;
2067 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2068 break;
2069 case 1: // result code
2070 {
2071 uint16_t rescode = ntohs(*(uint16_t *) b);
2072 const char* resdesc = "(unknown)";
2073 if (message == 4)
2074 { /* StopCCN */
2075 resdesc = l2tp_stopccn_result_code(rescode);
2076 }
2077 else if (message == 14)
2078 { /* CDN */
2079 resdesc = l2tp_cdn_result_code(rescode);
2080 }
2081
2082 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2083 if (n >= 4)
2084 {
2085 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2086 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2087 }
2088 if (n > 4)
2089 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2090
2091 break;
2092 }
2093 break;
2094 case 2: // protocol version
2095 {
2096 version = ntohs(*(uint16_t *) (b));
2097 LOG(4, s, t, " Protocol version = %d\n", version);
2098 if (version && version != 0x0100)
2099 { // allow 0.0 and 1.0
2100 LOG(1, s, t, " Bad protocol version %04X\n", version);
2101 fatal = flags;
2102 result = 5; // unspported protocol version
2103 error = 0x0100; // supported version
2104 msg = 0;
2105 continue; // next
2106 }
2107 }
2108 break;
2109 case 3: // framing capabilities
2110 // LOG(4, s, t, "Framing capabilities\n");
2111 break;
2112 case 4: // bearer capabilities
2113 // LOG(4, s, t, "Bearer capabilities\n");
2114 break;
2115 case 5: // tie breaker
2116 // We never open tunnels, so we don't care about tie breakers
2117 // LOG(4, s, t, "Tie breaker\n");
2118 continue;
2119 case 6: // firmware revision
2120 // LOG(4, s, t, "Firmware revision\n");
2121 break;
2122 case 7: // host name
2123 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2124 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2125 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2126 // TBA - to send to RADIUS
2127 break;
2128 case 8: // vendor name
2129 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2130 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2131 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2132 break;
2133 case 9: // assigned tunnel
2134 tunnel[t].far = ntohs(*(uint16_t *) (b));
2135 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2136 break;
2137 case 10: // rx window
2138 tunnel[t].window = ntohs(*(uint16_t *) (b));
2139 if (!tunnel[t].window)
2140 tunnel[t].window = 1; // window of 0 is silly
2141 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2142 break;
2143 case 11: // Challenge
2144 {
2145 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2146 build_chap_response(b, 2, n, &chapresponse);
2147 }
2148 break;
2149 case 13: // Response
2150 // Why did they send a response? We never challenge.
2151 LOG(2, s, t, " received unexpected challenge response\n");
2152 break;
2153
2154 case 14: // assigned session
2155 asession = session[s].far = ntohs(*(uint16_t *) (b));
2156 LOG(4, s, t, " assigned session = %d\n", asession);
2157 break;
2158 case 15: // call serial number
2159 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2160 break;
2161 case 18: // bearer type
2162 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2163 // TBA - for RADIUS
2164 break;
2165 case 19: // framing type
2166 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2167 // TBA
2168 break;
2169 case 21: // called number
2170 memset(called, 0, sizeof(called));
2171 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2172 LOG(4, s, t, " Called <%s>\n", called);
2173 break;
2174 case 22: // calling number
2175 memset(calling, 0, sizeof(calling));
2176 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2177 LOG(4, s, t, " Calling <%s>\n", calling);
2178 break;
2179 case 23: // subtype
2180 break;
2181 case 24: // tx connect speed
2182 if (n == 4)
2183 {
2184 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2185 }
2186 else
2187 {
2188 // AS5300s send connect speed as a string
2189 char tmp[30];
2190 memset(tmp, 0, sizeof(tmp));
2191 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2192 session[s].tx_connect_speed = atol(tmp);
2193 }
2194 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2195 break;
2196 case 38: // rx connect speed
2197 if (n == 4)
2198 {
2199 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2200 }
2201 else
2202 {
2203 // AS5300s send connect speed as a string
2204 char tmp[30];
2205 memset(tmp, 0, sizeof(tmp));
2206 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2207 session[s].rx_connect_speed = atol(tmp);
2208 }
2209 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2210 break;
2211 case 25: // Physical Channel ID
2212 {
2213 uint32_t tmp = ntohl(*(uint32_t *) b);
2214 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2215 break;
2216 }
2217 case 29: // Proxy Authentication Type
2218 {
2219 uint16_t atype = ntohs(*(uint16_t *)b);
2220 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2221 break;
2222 }
2223 case 30: // Proxy Authentication Name
2224 {
2225 char authname[64];
2226 memset(authname, 0, sizeof(authname));
2227 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2228 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2229 authname);
2230 break;
2231 }
2232 case 31: // Proxy Authentication Challenge
2233 {
2234 LOG(4, s, t, " Proxy Auth Challenge\n");
2235 break;
2236 }
2237 case 32: // Proxy Authentication ID
2238 {
2239 uint16_t authid = ntohs(*(uint16_t *)(b));
2240 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2241 break;
2242 }
2243 case 33: // Proxy Authentication Response
2244 LOG(4, s, t, " Proxy Auth Response\n");
2245 break;
2246 case 27: // last sent lcp
2247 { // find magic number
2248 uint8_t *p = b, *e = p + n;
2249 while (p + 1 < e && p[1] && p + p[1] <= e)
2250 {
2251 if (*p == 5 && p[1] == 6) // Magic-Number
2252 amagic = ntohl(*(uint32_t *) (p + 2));
2253 else if (*p == 7) // Protocol-Field-Compression
2254 aflags |= SESSIONPFC;
2255 else if (*p == 8) // Address-and-Control-Field-Compression
2256 aflags |= SESSIONACFC;
2257 p += p[1];
2258 }
2259 }
2260 break;
2261 case 28: // last recv lcp confreq
2262 break;
2263 case 26: // Initial Received LCP CONFREQ
2264 break;
2265 case 39: // seq required - we control it as an LNS anyway...
2266 break;
2267 case 36: // Random Vector
2268 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2269 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2270 if (n > sizeof(session[s].random_vector))
2271 n = sizeof(session[s].random_vector);
2272 memcpy(session[s].random_vector, b, n);
2273 session[s].random_vector_length = n;
2274 break;
2275 default:
2276 {
2277 static char e[] = "unknown AVP 0xXXXX";
2278 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2279 fatal = flags;
2280 result = 2; // general error
2281 error = 8; // unknown mandatory AVP
2282 sprintf((msg = e) + 14, "%04x", mtype);
2283 continue; // next
2284 }
2285 }
2286 }
2287 // process message
2288 if (fatal & 0x80)
2289 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2290 else
2291 switch (message)
2292 {
2293 case 1: // SCCRQ - Start Control Connection Request
2294 tunnel[t].state = TUNNELOPENING;
2295 if (main_quit != QUIT_SHUTDOWN)
2296 {
2297 controlt *c = controlnew(2); // sending SCCRP
2298 control16(c, 2, version, 1); // protocol version
2299 control32(c, 3, 3, 1); // framing
2300 controls(c, 7, hostname, 1); // host name
2301 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2302 control16(c, 9, t, 1); // assigned tunnel
2303 controladd(c, 0, t); // send the resply
2304 }
2305 else
2306 {
2307 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2308 }
2309 break;
2310 case 2: // SCCRP
2311 tunnel[t].state = TUNNELOPEN;
2312 break;
2313 case 3: // SCCN
2314 tunnel[t].state = TUNNELOPEN;
2315 controlnull(t); // ack
2316 break;
2317 case 4: // StopCCN
2318 controlnull(t); // ack
2319 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2320 break;
2321 case 6: // HELLO
2322 controlnull(t); // simply ACK
2323 break;
2324 case 7: // OCRQ
2325 // TBA
2326 break;
2327 case 8: // OCRO
2328 // TBA
2329 break;
2330 case 9: // OCCN
2331 // TBA
2332 break;
2333 case 10: // ICRQ
2334 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2335 {
2336 controlt *c = controlnew(11); // ICRP
2337
2338 s = sessionfree;
2339 sessionfree = session[s].next;
2340 memset(&session[s], 0, sizeof(session[s]));
2341
2342 if (s > config->cluster_highest_sessionid)
2343 config->cluster_highest_sessionid = s;
2344
2345 session[s].opened = time_now;
2346 session[s].tunnel = t;
2347 session[s].far = asession;
2348 session[s].last_packet = time_now;
2349 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2350 control16(c, 14, s, 1); // assigned session
2351 controladd(c, asession, t); // send the reply
2352
2353 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2354 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2355
2356 session[s].ppp.phase = Establish;
2357 session[s].ppp.lcp = Starting;
2358
2359 STAT(session_created);
2360 break;
2361 }
2362
2363 {
2364 controlt *c = controlnew(14); // CDN
2365 if (!sessionfree)
2366 {
2367 STAT(session_overflow);
2368 LOG(1, 0, t, "No free sessions\n");
2369 control16(c, 1, 4, 0); // temporary lack of resources
2370 }
2371 else
2372 control16(c, 1, 2, 7); // shutting down, try another
2373
2374 controladd(c, asession, t); // send the message
2375 }
2376 return;
2377 case 11: // ICRP
2378 // TBA
2379 break;
2380 case 12: // ICCN
2381 if (amagic == 0) amagic = time_now;
2382 session[s].magic = amagic; // set magic number
2383 session[s].l2tp_flags = aflags; // set flags received
2384 session[s].mru = DEFAULT_MRU;
2385 controlnull(t); // ack
2386
2387 // start LCP
2388 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2389 sess_local[s].lcp.conf_sent = 1;
2390 sess_local[s].lcp.nak_sent = 0;
2391 sess_local[s].lcp_authtype = config->radius_authprefer;
2392 session[s].ppp.lcp = RequestSent;
2393 sendlcp(s, t);
2394
2395 break;
2396 case 14: // CDN
2397 controlnull(t); // ack
2398 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2399 break;
2400 case 0xFFFF:
2401 LOG(1, s, t, "Missing message type\n");
2402 break;
2403 default:
2404 STAT(tunnel_rx_errors);
2405 if (mandatory)
2406 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2407 else
2408 LOG(1, s, t, "Unknown message type %d\n", message);
2409 break;
2410 }
2411 if (chapresponse) free(chapresponse);
2412 cluster_send_tunnel(t);
2413 }
2414 else
2415 {
2416 LOG(4, s, t, " Got a ZLB ack\n");
2417 }
2418 }
2419 else
2420 { // data
2421 uint16_t proto;
2422
2423 LOG_HEX(5, "Receive Tunnel Data", p, l);
2424 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2425 { // HDLC address header, discard
2426 p += 2;
2427 l -= 2;
2428 }
2429 if (l < 2)
2430 {
2431 LOG(1, s, t, "Short ppp length %d\n", l);
2432 STAT(tunnel_rx_errors);
2433 return;
2434 }
2435 if (*p & 1)
2436 {
2437 proto = *p++;
2438 l--;
2439 }
2440 else
2441 {
2442 proto = ntohs(*(uint16_t *) p);
2443 p += 2;
2444 l -= 2;
2445 }
2446
2447 if (s && !session[s].opened) // Is something wrong??
2448 {
2449 if (!config->cluster_iam_master)
2450 {
2451 // Pass it off to the master to deal with..
2452 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2453 return;
2454 }
2455
2456
2457 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2458 STAT(tunnel_rx_errors);
2459 return;
2460 }
2461
2462 if (proto == PPPPAP)
2463 {
2464 session[s].last_packet = time_now;
2465 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2466 processpap(s, t, p, l);
2467 }
2468 else if (proto == PPPCHAP)
2469 {
2470 session[s].last_packet = time_now;
2471 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2472 processchap(s, t, p, l);
2473 }
2474 else if (proto == PPPLCP)
2475 {
2476 session[s].last_packet = time_now;
2477 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2478 processlcp(s, t, p, l);
2479 }
2480 else if (proto == PPPIPCP)
2481 {
2482 session[s].last_packet = time_now;
2483 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2484 processipcp(s, t, p, l);
2485 }
2486 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2487 {
2488 session[s].last_packet = time_now;
2489 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2490 processipv6cp(s, t, p, l);
2491 }
2492 else if (proto == PPPCCP)
2493 {
2494 session[s].last_packet = time_now;
2495 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2496 processccp(s, t, p, l);
2497 }
2498 else if (proto == PPPIP)
2499 {
2500 if (session[s].die)
2501 {
2502 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2503 return; // closing session, PPP not processed
2504 }
2505
2506 session[s].last_packet = time_now;
2507 if (session[s].walled_garden && !config->cluster_iam_master)
2508 {
2509 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2510 return;
2511 }
2512
2513 processipin(s, t, p, l);
2514 }
2515 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2516 {
2517 if (session[s].die)
2518 {
2519 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2520 return; // closing session, PPP not processed
2521 }
2522
2523 session[s].last_packet = time_now;
2524 if (session[s].walled_garden && !config->cluster_iam_master)
2525 {
2526 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2527 return;
2528 }
2529
2530 processipv6in(s, t, p, l);
2531 }
2532 else if (session[s].ppp.lcp == Opened)
2533 {
2534 uint8_t buf[MAXETHER];
2535 uint8_t *q;
2536 int mru = session[s].mru;
2537
2538 if (!mru) mru = MAXMRU;
2539 if (mru > sizeof(buf)) mru = sizeof(buf);
2540
2541 l += 6;
2542 if (l > mru) l = mru;
2543
2544 q = makeppp(buf, sizeof(buf), 0, 0, s, t, proto);
2545 if (!q) return;
2546
2547 *q = CodeRej;
2548 *(q + 1) = ++sess_local[s].lcp_ident;
2549 *(uint16_t *)(q + 2) = l;
2550 *(uint16_t *)(q + 4) = htons(proto);
2551 memcpy(q + 6, p, l - 6);
2552
2553 if (proto == PPPIPV6CP)
2554 LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n");
2555 else
2556 LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto);
2557
2558 tunnelsend(buf, l + (q - buf), t);
2559 }
2560 else
2561 {
2562 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2563 proto, ppp_state(session[s].ppp.lcp));
2564 }
2565 }
2566 }
2567
2568 // read and process packet on tun
2569 static void processtun(uint8_t * buf, int len)
2570 {
2571 LOG_HEX(5, "Receive TUN Data", buf, len);
2572 STAT(tun_rx_packets);
2573 INC_STAT(tun_rx_bytes, len);
2574
2575 CSTAT(processtun);
2576
2577 eth_rx_pkt++;
2578 eth_rx += len;
2579 if (len < 22)
2580 {
2581 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2582 STAT(tun_rx_errors);
2583 return;
2584 }
2585
2586 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2587 processipout(buf, len);
2588 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2589 && config->ipv6_prefix.s6_addr[0])
2590 processipv6out(buf, len);
2591
2592 // Else discard.
2593 }
2594
2595 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2596 // that we look at the whole of the tunnel, radius and session tables
2597 // every second
2598 static void regular_cleanups(double period)
2599 {
2600 // Next tunnel, radius and session to check for actions on.
2601 static tunnelidt t = 0;
2602 static int r = 0;
2603 static sessionidt s = 0;
2604
2605 int t_actions = 0;
2606 int r_actions = 0;
2607 int s_actions = 0;
2608
2609 int t_slice;
2610 int r_slice;
2611 int s_slice;
2612
2613 int i;
2614 int a;
2615
2616 // divide up tables into slices based on the last run
2617 t_slice = config->cluster_highest_tunnelid * period;
2618 r_slice = (MAXRADIUS - 1) * period;
2619 s_slice = config->cluster_highest_sessionid * period;
2620
2621 if (t_slice < 1)
2622 t_slice = 1;
2623 else if (t_slice > config->cluster_highest_tunnelid)
2624 t_slice = config->cluster_highest_tunnelid;
2625
2626 if (r_slice < 1)
2627 r_slice = 1;
2628 else if (r_slice > (MAXRADIUS - 1))
2629 r_slice = MAXRADIUS - 1;
2630
2631 if (s_slice < 1)
2632 s_slice = 1;
2633 else if (s_slice > config->cluster_highest_sessionid)
2634 s_slice = config->cluster_highest_sessionid;
2635
2636 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2637
2638 for (i = 0; i < t_slice; i++)
2639 {
2640 t++;
2641 if (t > config->cluster_highest_tunnelid)
2642 t = 1;
2643
2644 // check for expired tunnels
2645 if (tunnel[t].die && tunnel[t].die <= TIME)
2646 {
2647 STAT(tunnel_timeout);
2648 tunnelkill(t, "Expired");
2649 t_actions++;
2650 continue;
2651 }
2652 // check for message resend
2653 if (tunnel[t].retry && tunnel[t].controlc)
2654 {
2655 // resend pending messages as timeout on reply
2656 if (tunnel[t].retry <= TIME)
2657 {
2658 controlt *c = tunnel[t].controls;
2659 uint8_t w = tunnel[t].window;
2660 tunnel[t].try++; // another try
2661 if (tunnel[t].try > 5)
2662 tunnelkill(t, "Timeout on control message"); // game over
2663 else
2664 while (c && w--)
2665 {
2666 tunnelsend(c->buf, c->length, t);
2667 c = c->next;
2668 }
2669
2670 t_actions++;
2671 }
2672 }
2673 // Send hello
2674 if (tunnel[t].state == TUNNELOPEN && (time_now - tunnel[t].lastrec) > 60)
2675 {
2676 controlt *c = controlnew(6); // sending HELLO
2677 controladd(c, 0, t); // send the message
2678 LOG(3, 0, t, "Sending HELLO message\n");
2679 t_actions++;
2680 }
2681
2682 // Check for tunnel changes requested from the CLI
2683 if ((a = cli_tunnel_actions[t].action))
2684 {
2685 cli_tunnel_actions[t].action = 0;
2686 if (a & CLI_TUN_KILL)
2687 {
2688 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2689 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2690 t_actions++;
2691 }
2692 }
2693 }
2694
2695 for (i = 0; i < r_slice; i++)
2696 {
2697 r++;
2698 if (r >= MAXRADIUS)
2699 r = 1;
2700
2701 if (!radius[r].state)
2702 continue;
2703
2704 if (radius[r].retry <= TIME)
2705 {
2706 radiusretry(r);
2707 r_actions++;
2708 }
2709 }
2710
2711 for (i = 0; i < s_slice; i++)
2712 {
2713 s++;
2714 if (s > config->cluster_highest_sessionid)
2715 s = 1;
2716
2717 if (!session[s].opened) // Session isn't in use
2718 continue;
2719
2720 // check for expired sessions
2721 if (session[s].die)
2722 {
2723 if (session[s].die <= TIME)
2724 {
2725 sessionkill(s, "Expired");
2726 s_actions++;
2727 }
2728 continue;
2729 }
2730
2731 // PPP timeouts
2732 if (sess_local[s].lcp.restart <= time_now)
2733 {
2734 int next_state = session[s].ppp.lcp;
2735 switch (session[s].ppp.lcp)
2736 {
2737 case RequestSent:
2738 case AckReceived:
2739 next_state = RequestSent;
2740
2741 case AckSent:
2742 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2743 {
2744 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2745 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2746 sess_local[s].lcp.conf_sent++;
2747 sendlcp(s, session[s].tunnel);
2748 change_state(s, lcp, next_state);
2749 }
2750 else
2751 {
2752 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2753 STAT(session_timeout);
2754 }
2755
2756 s_actions++;
2757 }
2758
2759 if (session[s].die)
2760 continue;
2761 }
2762
2763 if (sess_local[s].ipcp.restart <= time_now)
2764 {
2765 int next_state = session[s].ppp.ipcp;
2766 switch (session[s].ppp.ipcp)
2767 {
2768 case RequestSent:
2769 case AckReceived:
2770 next_state = RequestSent;
2771
2772 case AckSent:
2773 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2774 {
2775 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2776 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2777 sess_local[s].ipcp.conf_sent++;
2778 sendipcp(s, session[s].tunnel);
2779 change_state(s, ipcp, next_state);
2780 }
2781 else
2782 {
2783 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2784 STAT(session_timeout);
2785 }
2786
2787 s_actions++;
2788 }
2789
2790 if (session[s].die)
2791 continue;
2792 }
2793
2794 if (sess_local[s].ipv6cp.restart <= time_now)
2795 {
2796 int next_state = session[s].ppp.ipv6cp;
2797 switch (session[s].ppp.ipv6cp)
2798 {
2799 case RequestSent:
2800 case AckReceived:
2801 next_state = RequestSent;
2802
2803 case AckSent:
2804 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2805 {
2806 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2807 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2808 sess_local[s].ipv6cp.conf_sent++;
2809 sendipv6cp(s, session[s].tunnel);
2810 change_state(s, ipv6cp, next_state);
2811 }
2812 else
2813 {
2814 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2815 change_state(s, ipv6cp, Stopped);
2816 }
2817
2818 s_actions++;
2819 }
2820 }
2821
2822 if (sess_local[s].ccp.restart <= time_now)
2823 {
2824 int next_state = session[s].ppp.ccp;
2825 switch (session[s].ppp.ccp)
2826 {
2827 case RequestSent:
2828 case AckReceived:
2829 next_state = RequestSent;
2830
2831 case AckSent:
2832 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2833 {
2834 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2835 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2836 sess_local[s].ccp.conf_sent++;
2837 sendccp(s, session[s].tunnel);
2838 change_state(s, ccp, next_state);
2839 }
2840 else
2841 {
2842 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2843 change_state(s, ccp, Stopped);
2844 }
2845
2846 s_actions++;
2847 }
2848 }
2849
2850 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2851 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2852 {
2853 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2854 STAT(session_timeout);
2855 s_actions++;
2856 continue;
2857 }
2858
2859 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2860 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2861 {
2862 uint8_t b[MAXETHER];
2863
2864 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2865 if (!q) continue;
2866
2867 *q = EchoReq;
2868 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2869 *(uint16_t *)(q + 2) = htons(8); // Length
2870 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2871
2872 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2873 (int)(time_now - session[s].last_packet));
2874 tunnelsend(b, 24, session[s].tunnel); // send it
2875 s_actions++;
2876 }
2877
2878 // Check for actions requested from the CLI
2879 if ((a = cli_session_actions[s].action))
2880 {
2881 int send = 0;
2882
2883 cli_session_actions[s].action = 0;
2884 if (a & CLI_SESS_KILL)
2885 {
2886 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2887 sessionshutdown(s, "Requested by administrator.", 3, 0);
2888 a = 0; // dead, no need to check for other actions
2889 s_actions++;
2890 }
2891
2892 if (a & CLI_SESS_NOSNOOP)
2893 {
2894 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2895 session[s].snoop_ip = 0;
2896 session[s].snoop_port = 0;
2897 s_actions++;
2898 send++;
2899 }
2900 else if (a & CLI_SESS_SNOOP)
2901 {
2902 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2903 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2904 cli_session_actions[s].snoop_port);
2905
2906 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2907 session[s].snoop_port = cli_session_actions[s].snoop_port;
2908 s_actions++;
2909 send++;
2910 }
2911
2912 if (a & CLI_SESS_NOTHROTTLE)
2913 {
2914 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2915 throttle_session(s, 0, 0);
2916 s_actions++;
2917 send++;
2918 }
2919 else if (a & CLI_SESS_THROTTLE)
2920 {
2921 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2922 cli_session_actions[s].throttle_in,
2923 cli_session_actions[s].throttle_out);
2924
2925 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2926 s_actions++;
2927 send++;
2928 }
2929
2930 if (a & CLI_SESS_NOFILTER)
2931 {
2932 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2933 filter_session(s, 0, 0);
2934 s_actions++;
2935 send++;
2936 }
2937 else if (a & CLI_SESS_FILTER)
2938 {
2939 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2940 cli_session_actions[s].filter_in,
2941 cli_session_actions[s].filter_out);
2942
2943 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2944 s_actions++;
2945 send++;
2946 }
2947
2948 if (send)
2949 cluster_send_session(s);
2950 }
2951
2952 // RADIUS interim accounting
2953 if (config->radius_accounting && config->radius_interim > 0
2954 && session[s].ip && !session[s].walled_garden
2955 && !sess_local[s].radius // RADIUS already in progress
2956 && time_now - sess_local[s].last_interim >= config->radius_interim)
2957 {
2958 int rad = radiusnew(s);
2959 if (!rad)
2960 {
2961 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2962 STAT(radius_overflow);
2963 continue;
2964 }
2965
2966 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2967 session[s].user, session[s].unique_id);
2968
2969 radiussend(rad, RADIUSINTERIM);
2970 sess_local[s].last_interim = time_now;
2971 s_actions++;
2972 }
2973 }
2974
2975 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2976 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2977 }
2978
2979 //
2980 // Are we in the middle of a tunnel update, or radius
2981 // requests??
2982 //
2983 static int still_busy(void)
2984 {
2985 int i;
2986 static clockt last_talked = 0;
2987 static clockt start_busy_wait = 0;
2988
2989 if (!config->cluster_iam_master)
2990 {
2991 #ifdef BGP
2992 static time_t stopped_bgp = 0;
2993 if (bgp_configured)
2994 {
2995 if (!stopped_bgp)
2996 {
2997 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2998
2999 for (i = 0; i < BGP_NUM_PEERS; i++)
3000 if (bgp_peers[i].state == Established)
3001 bgp_stop(&bgp_peers[i]);
3002
3003 stopped_bgp = time_now;
3004
3005 // we don't want to become master
3006 cluster_send_ping(0);
3007
3008 return 1;
3009 }
3010
3011 if (time_now < (stopped_bgp + QUIT_DELAY))
3012 return 1;
3013 }
3014 #endif /* BGP */
3015
3016 return 0;
3017 }
3018
3019 if (main_quit == QUIT_SHUTDOWN)
3020 {
3021 static int dropped = 0;
3022 if (!dropped)
3023 {
3024 int i;
3025
3026 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3027 for (i = 1; i < MAXTUNNEL; i++)
3028 if (tunnel[i].ip || tunnel[i].state)
3029 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3030
3031 dropped = 1;
3032 }
3033 }
3034
3035 if (start_busy_wait == 0)
3036 start_busy_wait = TIME;
3037
3038 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3039 {
3040 if (!tunnel[i].controlc)
3041 continue;
3042
3043 if (last_talked != TIME)
3044 {
3045 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3046 last_talked = TIME;
3047 }
3048 return 1;
3049 }
3050
3051 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3052 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3053 {
3054 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3055 return 0;
3056 }
3057
3058 for (i = 1; i < MAXRADIUS; i++)
3059 {
3060 if (radius[i].state == RADIUSNULL)
3061 continue;
3062 if (radius[i].state == RADIUSWAIT)
3063 continue;
3064
3065 if (last_talked != TIME)
3066 {
3067 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3068 last_talked = TIME;
3069 }
3070 return 1;
3071 }
3072
3073 return 0;
3074 }
3075
3076 #ifdef HAVE_EPOLL
3077 # include <sys/epoll.h>
3078 #else
3079 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3080 # include "fake_epoll.h"
3081 #endif
3082
3083 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3084 #define BASE_FDS 6
3085
3086 // additional polled fds
3087 #ifdef BGP
3088 # define EXTRA_FDS BGP_NUM_PEERS
3089 #else
3090 # define EXTRA_FDS 0
3091 #endif
3092
3093 // main loop - gets packets on tun or udp and processes them
3094 static void mainloop(void)
3095 {
3096 int i;
3097 uint8_t buf[65536];
3098 clockt next_cluster_ping = 0; // send initial ping immediately
3099 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3100 int maxevent = sizeof(events)/sizeof(*events);
3101
3102 if ((epollfd = epoll_create(maxevent)) < 0)
3103 {
3104 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3105 exit(1);
3106 }
3107
3108 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3109 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3110
3111 /* setup our fds to poll for input */
3112 {
3113 static struct event_data d[BASE_FDS];
3114 struct epoll_event e;
3115
3116 e.events = EPOLLIN;
3117 i = 0;
3118
3119 d[i].type = FD_TYPE_CLI;
3120 e.data.ptr = &d[i++];
3121 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3122
3123 d[i].type = FD_TYPE_CLUSTER;
3124 e.data.ptr = &d[i++];
3125 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3126
3127 d[i].type = FD_TYPE_TUN;
3128 e.data.ptr = &d[i++];
3129 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3130
3131 d[i].type = FD_TYPE_UDP;
3132 e.data.ptr = &d[i++];
3133 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3134
3135 d[i].type = FD_TYPE_CONTROL;
3136 e.data.ptr = &d[i++];
3137 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3138
3139 d[i].type = FD_TYPE_DAE;
3140 e.data.ptr = &d[i++];
3141 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3142 }
3143
3144 #ifdef BGP
3145 signal(SIGPIPE, SIG_IGN);
3146 bgp_setup(config->as_number);
3147 if (config->bind_address)
3148 bgp_add_route(config->bind_address, 0xffffffff);
3149
3150 for (i = 0; i < BGP_NUM_PEERS; i++)
3151 {
3152 if (config->neighbour[i].name[0])
3153 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3154 config->neighbour[i].as, config->neighbour[i].keepalive,
3155 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3156 }
3157 #endif /* BGP */
3158
3159 while (!main_quit || still_busy())
3160 {
3161 int more = 0;
3162 int n;
3163
3164 if (config->reload_config)
3165 {
3166 // Update the config state based on config settings
3167 update_config();
3168 }
3169
3170 #ifdef BGP
3171 bgp_set_poll();
3172 #endif /* BGP */
3173
3174 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3175 STAT(select_called);
3176
3177 TIME = now(NULL);
3178 if (n < 0)
3179 {
3180 if (errno == EINTR ||
3181 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3182 continue;
3183
3184 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3185 break; // exit
3186 }
3187
3188 if (n)
3189 {
3190 struct sockaddr_in addr;
3191 socklen_t alen;
3192 int c, s;
3193 int udp_ready = 0;
3194 int tun_ready = 0;
3195 int cluster_ready = 0;
3196 int udp_pkts = 0;
3197 int tun_pkts = 0;
3198 int cluster_pkts = 0;
3199 #ifdef BGP
3200 uint32_t bgp_events[BGP_NUM_PEERS];
3201 memset(bgp_events, 0, sizeof(bgp_events));
3202 #endif /* BGP */
3203
3204 for (c = n, i = 0; i < c; i++)
3205 {
3206 struct event_data *d = events[i].data.ptr;
3207 switch (d->type)
3208 {
3209 case FD_TYPE_CLI: // CLI connections
3210 {
3211 int cli;
3212
3213 alen = sizeof(addr);
3214 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3215 {
3216 cli_do(cli);
3217 close(cli);
3218 }
3219 else
3220 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3221
3222 n--;
3223 break;
3224 }
3225
3226 // these are handled below, with multiple interleaved reads
3227 case FD_TYPE_CLUSTER: cluster_ready++; break;
3228 case FD_TYPE_TUN: tun_ready++; break;
3229 case FD_TYPE_UDP: udp_ready++; break;
3230
3231 case FD_TYPE_CONTROL: // nsctl commands
3232 alen = sizeof(addr);
3233 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3234 n--;
3235 break;
3236
3237 case FD_TYPE_DAE: // DAE requests
3238 alen = sizeof(addr);
3239 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3240 n--;
3241 break;
3242
3243 case FD_TYPE_RADIUS: // RADIUS response
3244 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3245 if (s >= 0 && config->cluster_iam_master)
3246 processrad(buf, s, d->index);
3247
3248 n--;
3249 break;
3250
3251 #ifdef BGP
3252 case FD_TYPE_BGP:
3253 bgp_events[d->index] = events[i].events;
3254 n--;
3255 break;
3256 #endif /* BGP */
3257
3258 default:
3259 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3260 }
3261 }
3262
3263 #ifdef BGP
3264 bgp_process(bgp_events);
3265 #endif /* BGP */
3266
3267 for (c = 0; n && c < config->multi_read_count; c++)
3268 {
3269 // L2TP
3270 if (udp_ready)
3271 {
3272 alen = sizeof(addr);
3273 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3274 {
3275 processudp(buf, s, &addr);
3276 udp_pkts++;
3277 }
3278 else
3279 {
3280 udp_ready = 0;
3281 n--;
3282 }
3283 }
3284
3285 // incoming IP
3286 if (tun_ready)
3287 {
3288 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3289 {
3290 processtun(buf, s);
3291 tun_pkts++;
3292 }
3293 else
3294 {
3295 tun_ready = 0;
3296 n--;
3297 }
3298 }
3299
3300 // cluster
3301 if (cluster_ready)
3302 {
3303 alen = sizeof(addr);
3304 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3305 {
3306 processcluster(buf, s, addr.sin_addr.s_addr);
3307 cluster_pkts++;
3308 }
3309 else
3310 {
3311 cluster_ready = 0;
3312 n--;
3313 }
3314 }
3315 }
3316
3317 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3318 STAT(multi_read_used);
3319
3320 if (c >= config->multi_read_count)
3321 {
3322 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3323 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3324
3325 STAT(multi_read_exceeded);
3326 more++;
3327 }
3328 }
3329
3330 // Runs on every machine (master and slaves).
3331 if (next_cluster_ping <= TIME)
3332 {
3333 // Check to see which of the cluster is still alive..
3334
3335 cluster_send_ping(basetime); // Only does anything if we're a slave
3336 cluster_check_master(); // ditto.
3337
3338 cluster_heartbeat(); // Only does anything if we're a master.
3339 cluster_check_slaves(); // ditto.
3340
3341 master_update_counts(); // If we're a slave, send our byte counters to our master.
3342
3343 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3344 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3345 else
3346 next_cluster_ping = TIME + config->cluster_hb_interval;
3347 }
3348
3349 if (!config->cluster_iam_master)
3350 continue;
3351
3352 // Run token bucket filtering queue..
3353 // Only run it every 1/10th of a second.
3354 {
3355 static clockt last_run = 0;
3356 if (last_run != TIME)
3357 {
3358 last_run = TIME;
3359 tbf_run_timer();
3360 }
3361 }
3362
3363 // Handle timeouts, retries etc.
3364 {
3365 static double last_clean = 0;
3366 double this_clean;
3367 double diff;
3368
3369 TIME = now(&this_clean);
3370 diff = this_clean - last_clean;
3371
3372 // Run during idle time (after we've handled
3373 // all incoming packets) or every 1/10th sec
3374 if (!more || diff > 0.1)
3375 {
3376 regular_cleanups(diff);
3377 last_clean = this_clean;
3378 }
3379 }
3380
3381 if (*config->accounting_dir)
3382 {
3383 static clockt next_acct = 0;
3384 static clockt next_shut_acct = 0;
3385
3386 if (next_acct <= TIME)
3387 {
3388 // Dump accounting data
3389 next_acct = TIME + ACCT_TIME;
3390 next_shut_acct = TIME + ACCT_SHUT_TIME;
3391 dump_acct_info(1);
3392 }
3393 else if (next_shut_acct <= TIME)
3394 {
3395 // Dump accounting data for shutdown sessions
3396 next_shut_acct = TIME + ACCT_SHUT_TIME;
3397 if (shut_acct_n)
3398 dump_acct_info(0);
3399 }
3400 }
3401 }
3402
3403 // Are we the master and shutting down??
3404 if (config->cluster_iam_master)
3405 cluster_heartbeat(); // Flush any queued changes..
3406
3407 // Ok. Notify everyone we're shutting down. If we're
3408 // the master, this will force an election.
3409 cluster_send_ping(0);
3410
3411 //
3412 // Important!!! We MUST not process any packets past this point!
3413 LOG(1, 0, 0, "Shutdown complete\n");
3414 }
3415
3416 static void stripdomain(char *host)
3417 {
3418 char *p;
3419
3420 if ((p = strchr(host, '.')))
3421 {
3422 char *domain = 0;
3423 char _domain[1024];
3424
3425 // strip off domain
3426 FILE *resolv = fopen("/etc/resolv.conf", "r");
3427 if (resolv)
3428 {
3429 char buf[1024];
3430 char *b;
3431
3432 while (fgets(buf, sizeof(buf), resolv))
3433 {
3434 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3435 continue;
3436
3437 if (!isspace(buf[6]))
3438 continue;
3439
3440 b = buf + 7;
3441 while (isspace(*b)) b++;
3442
3443 if (*b)
3444 {
3445 char *d = b;
3446 while (*b && !isspace(*b)) b++;
3447 *b = 0;
3448 if (buf[0] == 'd') // domain is canonical
3449 {
3450 domain = d;
3451 break;
3452 }
3453
3454 // first search line
3455 if (!domain)
3456 {
3457 // hold, may be subsequent domain line
3458 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3459 domain = _domain;
3460 }
3461 }
3462 }
3463
3464 fclose(resolv);
3465 }
3466
3467 if (domain)
3468 {
3469 int hl = strlen(host);
3470 int dl = strlen(domain);
3471 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3472 host[hl -dl - 1] = 0;
3473 }
3474 else
3475 {
3476 *p = 0; // everything after first dot
3477 }
3478 }
3479 }
3480
3481 // Init data structures
3482 static void initdata(int optdebug, char *optconfig)
3483 {
3484 int i;
3485
3486 if (!(config = shared_malloc(sizeof(configt))))
3487 {
3488 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3489 exit(1);
3490 }
3491
3492 memset(config, 0, sizeof(configt));
3493 time(&config->start_time);
3494 strncpy(config->config_file, optconfig, strlen(optconfig));
3495 config->debug = optdebug;
3496 config->num_tbfs = MAXTBFS;
3497 config->rl_rate = 28; // 28kbps
3498 config->cluster_mcast_ttl = 1;
3499 config->cluster_master_min_adv = 1;
3500 config->ppp_restart_time = 3;
3501 config->ppp_max_configure = 10;
3502 config->ppp_max_failure = 5;
3503 strcpy(config->random_device, RANDOMDEVICE);
3504
3505 log_stream = stderr;
3506
3507 #ifdef RINGBUFFER
3508 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3509 {
3510 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3511 exit(1);
3512 }
3513 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3514 #endif
3515
3516 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3517 {
3518 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3519 exit(1);
3520 }
3521 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3522 {
3523 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3524 exit(1);
3525 }
3526 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3527 {
3528 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3529 exit(1);
3530 }
3531
3532 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3533 {
3534 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3535 exit(1);
3536 }
3537
3538 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3539 {
3540 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3541 exit(1);
3542 }
3543
3544 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3545 {
3546 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3547 exit(1);
3548 }
3549
3550 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3551 {
3552 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3553 exit(1);
3554 }
3555 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3556
3557 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3558 {
3559 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3560 exit(1);
3561 }
3562 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3563
3564 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3565 {
3566 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3567 exit(1);
3568 }
3569 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3570
3571 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3572 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3573 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3574 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3575
3576 // Put all the sessions on the free list marked as undefined.
3577 for (i = 1; i < MAXSESSION; i++)
3578 {
3579 session[i].next = i + 1;
3580 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3581 }
3582 session[MAXSESSION - 1].next = 0;
3583 sessionfree = 1;
3584
3585 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3586 for (i = 1; i < MAXTUNNEL; i++)
3587 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3588
3589 if (!*hostname)
3590 {
3591 // Grab my hostname unless it's been specified
3592 gethostname(hostname, sizeof(hostname));
3593 stripdomain(hostname);
3594 }
3595
3596 _statistics->start_time = _statistics->last_reset = time(NULL);
3597
3598 #ifdef BGP
3599 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3600 {
3601 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3602 exit(1);
3603 }
3604 #endif /* BGP */
3605 }
3606
3607 static int assign_ip_address(sessionidt s)
3608 {
3609 uint32_t i;
3610 int best = -1;
3611 time_t best_time = time_now;
3612 char *u = session[s].user;
3613 char reuse = 0;
3614
3615
3616 CSTAT(assign_ip_address);
3617
3618 for (i = 1; i < ip_pool_size; i++)
3619 {
3620 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3621 continue;
3622
3623 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3624 {
3625 best = i;
3626 reuse = 1;
3627 break;
3628 }
3629
3630 if (ip_address_pool[i].last < best_time)
3631 {
3632 best = i;
3633 if (!(best_time = ip_address_pool[i].last))
3634 break; // never used, grab this one
3635 }
3636 }
3637
3638 if (best < 0)
3639 {
3640 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3641 return 0;
3642 }
3643
3644 session[s].ip = ip_address_pool[best].address;
3645 session[s].ip_pool_index = best;
3646 ip_address_pool[best].assigned = 1;
3647 ip_address_pool[best].last = time_now;
3648 ip_address_pool[best].session = s;
3649 if (session[s].walled_garden)
3650 /* Don't track addresses of users in walled garden (note: this
3651 means that their address isn't "sticky" even if they get
3652 un-gardened). */
3653 ip_address_pool[best].user[0] = 0;
3654 else
3655 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3656
3657 STAT(ip_allocated);
3658 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3659 reuse ? "Reusing" : "Allocating", best);
3660
3661 return 1;
3662 }
3663
3664 static void free_ip_address(sessionidt s)
3665 {
3666 int i = session[s].ip_pool_index;
3667
3668
3669 CSTAT(free_ip_address);
3670
3671 if (!session[s].ip)
3672 return; // what the?
3673
3674 if (i < 0) // Is this actually part of the ip pool?
3675 i = 0;
3676
3677 STAT(ip_freed);
3678 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3679 session[s].ip = 0;
3680 ip_address_pool[i].assigned = 0;
3681 ip_address_pool[i].session = 0;
3682 ip_address_pool[i].last = time_now;
3683 }
3684
3685 //
3686 // Fsck the address pool against the session table.
3687 // Normally only called when we become a master.
3688 //
3689 // This isn't perfect: We aren't keep tracking of which
3690 // users used to have an IP address.
3691 //
3692 void rebuild_address_pool(void)
3693 {
3694 int i;
3695
3696 //
3697 // Zero the IP pool allocation, and build
3698 // a map from IP address to pool index.
3699 for (i = 1; i < MAXIPPOOL; ++i)
3700 {
3701 ip_address_pool[i].assigned = 0;
3702 ip_address_pool[i].session = 0;
3703 if (!ip_address_pool[i].address)
3704 continue;
3705
3706 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3707 }
3708
3709 for (i = 0; i < MAXSESSION; ++i)
3710 {
3711 int ipid;
3712 if (!(session[i].opened && session[i].ip))
3713 continue;
3714
3715 ipid = - lookup_ipmap(htonl(session[i].ip));
3716
3717 if (session[i].ip_pool_index < 0)
3718 {
3719 // Not allocated out of the pool.
3720 if (ipid < 1) // Not found in the pool either? good.
3721 continue;
3722
3723 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3724 i, fmtaddr(session[i].ip, 0), ipid);
3725
3726 // Fall through and process it as part of the pool.
3727 }
3728
3729
3730 if (ipid > MAXIPPOOL || ipid < 0)
3731 {
3732 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3733 ipid = -1;
3734 session[i].ip_pool_index = ipid;
3735 continue;
3736 }
3737
3738 ip_address_pool[ipid].assigned = 1;
3739 ip_address_pool[ipid].session = i;
3740 ip_address_pool[ipid].last = time_now;
3741 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3742 session[i].ip_pool_index = ipid;
3743 cache_ipmap(session[i].ip, i); // Fix the ip map.
3744 }
3745 }
3746
3747 //
3748 // Fix the address pool to match a changed session.
3749 // (usually when the master sends us an update).
3750 static void fix_address_pool(int sid)
3751 {
3752 int ipid;
3753
3754 ipid = session[sid].ip_pool_index;
3755
3756 if (ipid > ip_pool_size)
3757 return; // Ignore it. rebuild_address_pool will fix it up.
3758
3759 if (ip_address_pool[ipid].address != session[sid].ip)
3760 return; // Just ignore it. rebuild_address_pool will take care of it.
3761
3762 ip_address_pool[ipid].assigned = 1;
3763 ip_address_pool[ipid].session = sid;
3764 ip_address_pool[ipid].last = time_now;
3765 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3766 }
3767
3768 //
3769 // Add a block of addresses to the IP pool to hand out.
3770 //
3771 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3772 {
3773 int i;
3774 if (mask == 0)
3775 mask = 0xffffffff; // Host route only.
3776
3777 addr &= mask;
3778
3779 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3780 return ;
3781
3782 for (i = addr ;(i & mask) == addr; ++i)
3783 {
3784 if ((i & 0xff) == 0 || (i&0xff) == 255)
3785 continue; // Skip 0 and broadcast addresses.
3786
3787 ip_address_pool[ip_pool_size].address = i;
3788 ip_address_pool[ip_pool_size].assigned = 0;
3789 ++ip_pool_size;
3790 if (ip_pool_size >= MAXIPPOOL)
3791 {
3792 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3793 return;
3794 }
3795 }
3796 }
3797
3798 // Initialize the IP address pool
3799 static void initippool()
3800 {
3801 FILE *f;
3802 char *p;
3803 char buf[4096];
3804 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3805
3806 if (!(f = fopen(IPPOOLFILE, "r")))
3807 {
3808 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3809 exit(1);
3810 }
3811
3812 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3813 {
3814 char *pool = buf;
3815 buf[4095] = 0; // Force it to be zero terminated/
3816
3817 if (*buf == '#' || *buf == '\n')
3818 continue; // Skip comments / blank lines
3819 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3820 if ((p = (char *)strchr(buf, ':')))
3821 {
3822 in_addr_t src;
3823 *p = '\0';
3824 src = inet_addr(buf);
3825 if (src == INADDR_NONE)
3826 {
3827 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3828 exit(1);
3829 }
3830 // This entry is for a specific IP only
3831 if (src != config->bind_address)
3832 continue;
3833 *p = ':';
3834 pool = p+1;
3835 }
3836 if ((p = (char *)strchr(pool, '/')))
3837 {
3838 // It's a range
3839 int numbits = 0;
3840 in_addr_t start = 0, mask = 0;
3841
3842 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3843 *p++ = 0;
3844 if (!*p || !(numbits = atoi(p)))
3845 {
3846 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3847 continue;
3848 }
3849 start = ntohl(inet_addr(pool));
3850 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3851
3852 // Add a static route for this pool
3853 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3854 fmtaddr(htonl(start), 0), 32 + mask);
3855
3856 routeset(0, start, mask, 0, 1);
3857
3858 add_to_ip_pool(start, mask);
3859 }
3860 else
3861 {
3862 // It's a single ip address
3863 add_to_ip_pool(inet_addr(pool), 0);
3864 }
3865 }
3866 fclose(f);
3867 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3868 }
3869
3870 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3871 {
3872 struct sockaddr_in snoop_addr = {0};
3873 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3874 return;
3875
3876 snoop_addr.sin_family = AF_INET;
3877 snoop_addr.sin_addr.s_addr = destination;
3878 snoop_addr.sin_port = ntohs(port);
3879
3880 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3881 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3882 htons(snoop_addr.sin_port));
3883
3884 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3885 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3886
3887 STAT(packets_snooped);
3888 }
3889
3890 static int dump_session(FILE **f, sessiont *s)
3891 {
3892 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3893 return 1;
3894
3895 if (!*f)
3896 {
3897 char filename[1024];
3898 char timestr[64];
3899 time_t now = time(NULL);
3900
3901 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3902 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3903
3904 if (!(*f = fopen(filename, "w")))
3905 {
3906 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3907 return 0;
3908 }
3909
3910 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3911 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3912 "# host: %s\n"
3913 "# endpoint: %s\n"
3914 "# time: %ld\n"
3915 "# uptime: %ld\n"
3916 "# format: username ip qos uptxoctets downrxoctets\n",
3917 hostname,
3918 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3919 now,
3920 now - basetime);
3921 }
3922
3923 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3924 fprintf(*f, "%s %s %d %u %u\n",
3925 s->user, // username
3926 fmtaddr(htonl(s->ip), 0), // ip
3927 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3928 (uint32_t) s->cin_delta, // uptxoctets
3929 (uint32_t) s->cout_delta); // downrxoctets
3930
3931 s->cin_delta = s->cout_delta = 0;
3932
3933 return 1;
3934 }
3935
3936 static void dump_acct_info(int all)
3937 {
3938 int i;
3939 FILE *f = NULL;
3940
3941
3942 CSTAT(dump_acct_info);
3943
3944 if (shut_acct_n)
3945 {
3946 for (i = 0; i < shut_acct_n; i++)
3947 dump_session(&f, &shut_acct[i]);
3948
3949 shut_acct_n = 0;
3950 }
3951
3952 if (all)
3953 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3954 dump_session(&f, &session[i]);
3955
3956 if (f)
3957 fclose(f);
3958 }
3959
3960 // Main program
3961 int main(int argc, char *argv[])
3962 {
3963 int i;
3964 int optdebug = 0;
3965 char *optconfig = CONFIGFILE;
3966
3967 time(&basetime); // start clock
3968
3969 // scan args
3970 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3971 {
3972 switch (i)
3973 {
3974 case 'd':
3975 if (fork()) exit(0);
3976 setsid();
3977 freopen("/dev/null", "r", stdin);
3978 freopen("/dev/null", "w", stdout);
3979 freopen("/dev/null", "w", stderr);
3980 break;
3981 case 'v':
3982 optdebug++;
3983 break;
3984 case 'c':
3985 optconfig = optarg;
3986 break;
3987 case 'h':
3988 snprintf(hostname, sizeof(hostname), "%s", optarg);
3989 break;
3990 default:
3991 printf("Args are:\n"
3992 "\t-d\t\tDetach from terminal\n"
3993 "\t-c <file>\tConfig file\n"
3994 "\t-h <hostname>\tForce hostname\n"
3995 "\t-v\t\tDebug\n");
3996
3997 return (0);
3998 break;
3999 }
4000 }
4001
4002 // Start the timer routine off
4003 time(&time_now);
4004 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4005 signal(SIGALRM, sigalrm_handler);
4006 siginterrupt(SIGALRM, 0);
4007
4008 initplugins();
4009 initdata(optdebug, optconfig);
4010
4011 init_cli(hostname);
4012 read_config_file();
4013 init_tbf(config->num_tbfs);
4014
4015 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4016 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4017 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4018 {
4019 struct rlimit rlim;
4020 rlim.rlim_cur = RLIM_INFINITY;
4021 rlim.rlim_max = RLIM_INFINITY;
4022 // Remove the maximum core size
4023 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4024 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4025
4026 // Make core dumps go to /tmp
4027 chdir("/tmp");
4028 }
4029
4030 if (config->scheduler_fifo)
4031 {
4032 int ret;
4033 struct sched_param params = {0};
4034 params.sched_priority = 1;
4035
4036 if (get_nprocs() < 2)
4037 {
4038 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4039 config->scheduler_fifo = 0;
4040 }
4041 else
4042 {
4043 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4044 {
4045 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4046 }
4047 else
4048 {
4049 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4050 config->scheduler_fifo = 0;
4051 }
4052 }
4053 }
4054
4055 /* Set up the cluster communications port. */
4056 if (cluster_init() < 0)
4057 exit(1);
4058
4059 inittun();
4060 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4061
4062 initudp();
4063 initrad();
4064 initippool();
4065
4066 // seed prng
4067 {
4068 unsigned seed = time_now ^ getpid();
4069 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4070 srand(seed);
4071 }
4072
4073 signal(SIGHUP, sighup_handler);
4074 signal(SIGCHLD, sigchild_handler);
4075 signal(SIGTERM, shutdown_handler);
4076 signal(SIGINT, shutdown_handler);
4077 signal(SIGQUIT, shutdown_handler);
4078
4079 // Prevent us from getting paged out
4080 if (config->lock_pages)
4081 {
4082 if (!mlockall(MCL_CURRENT))
4083 LOG(1, 0, 0, "Locking pages into memory\n");
4084 else
4085 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4086 }
4087
4088 alarm(1);
4089
4090 // Drop privileges here
4091 if (config->target_uid > 0 && geteuid() == 0)
4092 setuid(config->target_uid);
4093
4094 mainloop();
4095
4096 /* remove plugins (so cleanup code gets run) */
4097 plugins_done();
4098
4099 // Remove the PID file if we wrote it
4100 if (config->wrote_pid && *config->pid_file == '/')
4101 unlink(config->pid_file);
4102
4103 /* kill CLI children */
4104 signal(SIGTERM, SIG_IGN);
4105 kill(0, SIGTERM);
4106 return 0;
4107 }
4108
4109 static void sighup_handler(int sig)
4110 {
4111 if (log_stream)
4112 {
4113 if (log_stream != stderr)
4114 fclose(log_stream);
4115
4116 log_stream = NULL;
4117 }
4118
4119 read_config_file();
4120 }
4121
4122 static void sigalrm_handler(int sig)
4123 {
4124 // Log current traffic stats
4125
4126 snprintf(config->bandwidth, sizeof(config->bandwidth),
4127 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4128 (udp_rx / 1024.0 / 1024.0 * 8),
4129 (eth_tx / 1024.0 / 1024.0 * 8),
4130 (eth_rx / 1024.0 / 1024.0 * 8),
4131 (udp_tx / 1024.0 / 1024.0 * 8),
4132 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4133 udp_rx_pkt, eth_rx_pkt);
4134
4135 udp_tx = udp_rx = 0;
4136 udp_rx_pkt = eth_rx_pkt = 0;
4137 eth_tx = eth_rx = 0;
4138
4139 if (config->dump_speed)
4140 printf("%s\n", config->bandwidth);
4141
4142 // Update the internal time counter
4143 time(&time_now);
4144 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4145 alarm(1);
4146
4147 {
4148 // Run timer hooks
4149 struct param_timer p = { time_now };
4150 run_plugins(PLUGIN_TIMER, &p);
4151 }
4152
4153 }
4154
4155 static void shutdown_handler(int sig)
4156 {
4157 LOG(1, 0, 0, "Shutting down\n");
4158 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4159 }
4160
4161 static void sigchild_handler(int sig)
4162 {
4163 while (waitpid(-1, NULL, WNOHANG) > 0)
4164 ;
4165 }
4166
4167 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4168 {
4169 MD5_CTX ctx;
4170 *challenge_response = NULL;
4171
4172 if (!*config->l2tpsecret)
4173 {
4174 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4175 return;
4176 }
4177
4178 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4179
4180 *challenge_response = calloc(17, 1);
4181
4182 MD5_Init(&ctx);
4183 MD5_Update(&ctx, &id, 1);
4184 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4185 MD5_Update(&ctx, challenge, challenge_length);
4186 MD5_Final(*challenge_response, &ctx);
4187
4188 return;
4189 }
4190
4191 static int facility_value(char *name)
4192 {
4193 int i;
4194 for (i = 0; facilitynames[i].c_name; i++)
4195 {
4196 if (strcmp(facilitynames[i].c_name, name) == 0)
4197 return facilitynames[i].c_val;
4198 }
4199 return 0;
4200 }
4201
4202 static void update_config()
4203 {
4204 int i;
4205 char *p;
4206 static int timeout = 0;
4207 static int interval = 0;
4208
4209 // Update logging
4210 closelog();
4211 syslog_log = 0;
4212 if (log_stream)
4213 {
4214 if (log_stream != stderr)
4215 fclose(log_stream);
4216
4217 log_stream = NULL;
4218 }
4219
4220 if (*config->log_filename)
4221 {
4222 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4223 {
4224 char *p = config->log_filename + 7;
4225 if (*p)
4226 {
4227 openlog("l2tpns", LOG_PID, facility_value(p));
4228 syslog_log = 1;
4229 }
4230 }
4231 else if (strchr(config->log_filename, '/') == config->log_filename)
4232 {
4233 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4234 {
4235 fseek(log_stream, 0, SEEK_END);
4236 setbuf(log_stream, NULL);
4237 }
4238 else
4239 {
4240 log_stream = stderr;
4241 setbuf(log_stream, NULL);
4242 }
4243 }
4244 }
4245 else
4246 {
4247 log_stream = stderr;
4248 setbuf(log_stream, NULL);
4249 }
4250
4251 // Update radius
4252 config->numradiusservers = 0;
4253 for (i = 0; i < MAXRADSERVER; i++)
4254 if (config->radiusserver[i])
4255 {
4256 config->numradiusservers++;
4257 // Set radius port: if not set, take the port from the
4258 // first radius server. For the first radius server,
4259 // take the #defined default value from l2tpns.h
4260
4261 // test twice, In case someone works with
4262 // a secondary radius server without defining
4263 // a primary one, this will work even then.
4264 if (i > 0 && !config->radiusport[i])
4265 config->radiusport[i] = config->radiusport[i-1];
4266 if (!config->radiusport[i])
4267 config->radiusport[i] = RADPORT;
4268 }
4269
4270 if (!config->numradiusservers)
4271 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4272
4273 // parse radius_authtypes_s
4274 config->radius_authtypes = config->radius_authprefer = 0;
4275 p = config->radius_authtypes_s;
4276 while (p && *p)
4277 {
4278 char *s = strpbrk(p, " \t,");
4279 int type = 0;
4280
4281 if (s)
4282 {
4283 *s++ = 0;
4284 while (*s == ' ' || *s == '\t')
4285 s++;
4286
4287 if (!*s)
4288 s = 0;
4289 }
4290
4291 if (!strncasecmp("chap", p, strlen(p)))
4292 type = AUTHCHAP;
4293 else if (!strncasecmp("pap", p, strlen(p)))
4294 type = AUTHPAP;
4295 else
4296 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4297
4298 config->radius_authtypes |= type;
4299 if (!config->radius_authprefer)
4300 config->radius_authprefer = type;
4301
4302 p = s;
4303 }
4304
4305 if (!config->radius_authtypes)
4306 {
4307 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4308 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4309 }
4310
4311 // normalise radius_authtypes_s
4312 if (config->radius_authprefer == AUTHPAP)
4313 {
4314 strcpy(config->radius_authtypes_s, "pap");
4315 if (config->radius_authtypes & AUTHCHAP)
4316 strcat(config->radius_authtypes_s, ", chap");
4317 }
4318 else
4319 {
4320 strcpy(config->radius_authtypes_s, "chap");
4321 if (config->radius_authtypes & AUTHPAP)
4322 strcat(config->radius_authtypes_s, ", pap");
4323 }
4324
4325 if (!config->radius_dae_port)
4326 config->radius_dae_port = DAEPORT;
4327
4328 // re-initialise the random number source
4329 initrandom(config->random_device);
4330
4331 // Update plugins
4332 for (i = 0; i < MAXPLUGINS; i++)
4333 {
4334 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4335 continue;
4336
4337 if (*config->plugins[i])
4338 {
4339 // Plugin added
4340 add_plugin(config->plugins[i]);
4341 }
4342 else if (*config->old_plugins[i])
4343 {
4344 // Plugin removed
4345 remove_plugin(config->old_plugins[i]);
4346 }
4347 }
4348
4349 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4350 if (!config->multi_read_count) config->multi_read_count = 10;
4351 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4352 if (!*config->cluster_interface)
4353 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4354
4355 if (!config->cluster_hb_interval)
4356 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4357
4358 if (!config->cluster_hb_timeout)
4359 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4360
4361 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4362 {
4363 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4364 // late, ensure we're sufficiently larger than that
4365 int t = 4 * config->cluster_hb_interval + 11;
4366
4367 if (config->cluster_hb_timeout < t)
4368 {
4369 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4370 config->cluster_hb_timeout = t;
4371 }
4372
4373 // Push timing changes to the slaves immediately if we're the master
4374 if (config->cluster_iam_master)
4375 cluster_heartbeat();
4376
4377 interval = config->cluster_hb_interval;
4378 timeout = config->cluster_hb_timeout;
4379 }
4380
4381 // Write PID file
4382 if (*config->pid_file == '/' && !config->wrote_pid)
4383 {
4384 FILE *f;
4385 if ((f = fopen(config->pid_file, "w")))
4386 {
4387 fprintf(f, "%d\n", getpid());
4388 fclose(f);
4389 config->wrote_pid = 1;
4390 }
4391 else
4392 {
4393 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4394 }
4395 }
4396
4397 config->reload_config = 0;
4398 }
4399
4400 static void read_config_file()
4401 {
4402 FILE *f;
4403
4404 if (!config->config_file) return;
4405 if (!(f = fopen(config->config_file, "r")))
4406 {
4407 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4408 return;
4409 }
4410
4411 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4412 cli_do_file(f);
4413 LOG(3, 0, 0, "Done reading config file\n");
4414 fclose(f);
4415 update_config();
4416 }
4417
4418 int sessionsetup(sessionidt s, tunnelidt t)
4419 {
4420 // A session now exists, set it up
4421 in_addr_t ip;
4422 char *user;
4423 sessionidt i;
4424 int r;
4425
4426 CSTAT(sessionsetup);
4427
4428 LOG(3, s, t, "Doing session setup for session\n");
4429
4430 if (!session[s].ip)
4431 {
4432 assign_ip_address(s);
4433 if (!session[s].ip)
4434 {
4435 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4436 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4437 return 0;
4438 }
4439 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4440 fmtaddr(htonl(session[s].ip), 0));
4441 }
4442
4443
4444 // Make sure this is right
4445 session[s].tunnel = t;
4446
4447 // zap old sessions with same IP and/or username
4448 // Don't kill gardened sessions - doing so leads to a DoS
4449 // from someone who doesn't need to know the password
4450 {
4451 ip = session[s].ip;
4452 user = session[s].user;
4453 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4454 {
4455 if (i == s) continue;
4456 if (!session[s].opened) continue;
4457 if (ip == session[i].ip)
4458 {
4459 sessionkill(i, "Duplicate IP address");
4460 continue;
4461 }
4462
4463 if (config->allow_duplicate_users) continue;
4464 if (session[s].walled_garden || session[i].walled_garden) continue;
4465 if (!strcasecmp(user, session[i].user))
4466 sessionkill(i, "Duplicate session for users");
4467 }
4468 }
4469
4470 {
4471 int routed = 0;
4472
4473 // Add the route for this session.
4474 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4475 {
4476 if ((session[s].ip & session[s].route[r].mask) ==
4477 (session[s].route[r].ip & session[s].route[r].mask))
4478 routed++;
4479
4480 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4481 }
4482
4483 // Static IPs need to be routed if not already
4484 // convered by a Framed-Route. Anything else is part
4485 // of the IP address pool and is already routed, it
4486 // just needs to be added to the IP cache.
4487 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4488 if (session[s].ip_pool_index == -1) // static ip
4489 {
4490 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4491 }
4492 else
4493 cache_ipmap(session[s].ip, s);
4494 }
4495
4496 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4497 lcp_open(s, t); // transition to Network phase and send initial IPCP
4498
4499 // Run the plugin's against this new session.
4500 {
4501 struct param_new_session data = { &tunnel[t], &session[s] };
4502 run_plugins(PLUGIN_NEW_SESSION, &data);
4503 }
4504
4505 // Allocate TBFs if throttled
4506 if (session[s].throttle_in || session[s].throttle_out)
4507 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4508
4509 session[s].last_packet = time_now;
4510
4511 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4512 fmtaddr(htonl(session[s].ip), 0),
4513 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4514
4515 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4516
4517 return 1; // RADIUS OK and IP allocated, done...
4518 }
4519
4520 //
4521 // This session just got dropped on us by the master or something.
4522 // Make sure our tables up up to date...
4523 //
4524 int load_session(sessionidt s, sessiont *new)
4525 {
4526 int i;
4527 int newip = 0;
4528
4529 // Sanity checks.
4530 if (new->ip_pool_index >= MAXIPPOOL ||
4531 new->tunnel >= MAXTUNNEL)
4532 {
4533 LOG(0, s, 0, "Strange session update received!\n");
4534 // FIXME! What to do here?
4535 return 0;
4536 }
4537
4538 //
4539 // Ok. All sanity checks passed. Now we're committed to
4540 // loading the new session.
4541 //
4542
4543 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4544
4545 // See if routes/ip cache need updating
4546 if (new->ip != session[s].ip)
4547 newip++;
4548
4549 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4550 if (new->route[i].ip != session[s].route[i].ip ||
4551 new->route[i].mask != session[s].route[i].mask)
4552 newip++;
4553
4554 // needs update
4555 if (newip)
4556 {
4557 int routed = 0;
4558
4559 // remove old routes...
4560 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4561 {
4562 if ((session[s].ip & session[s].route[i].mask) ==
4563 (session[s].route[i].ip & session[s].route[i].mask))
4564 routed++;
4565
4566 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4567 }
4568
4569 // ...ip
4570 if (session[s].ip)
4571 {
4572 if (session[s].ip_pool_index == -1) // static IP
4573 {
4574 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4575 }
4576 else // It's part of the IP pool, remove it manually.
4577 uncache_ipmap(session[s].ip);
4578 }
4579
4580 routed = 0;
4581
4582 // add new routes...
4583 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4584 {
4585 if ((new->ip & new->route[i].mask) ==
4586 (new->route[i].ip & new->route[i].mask))
4587 routed++;
4588
4589 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4590 }
4591
4592 // ...ip
4593 if (new->ip)
4594 {
4595 // If there's a new one, add it.
4596 if (new->ip_pool_index == -1)
4597 {
4598 if (!routed) routeset(s, new->ip, 0, 0, 1);
4599 }
4600 else
4601 cache_ipmap(new->ip, s);
4602 }
4603 }
4604
4605 // check v6 routing
4606 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4607 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4608
4609 // check filters
4610 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4611 {
4612 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4613 new->filter_in = 0;
4614 }
4615
4616 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4617 {
4618 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4619 new->filter_out = 0;
4620 }
4621
4622 if (new->filter_in != session[s].filter_in)
4623 {
4624 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4625 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4626 }
4627
4628 if (new->filter_out != session[s].filter_out)
4629 {
4630 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4631 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4632 }
4633
4634 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4635 // for walking the sessions to forward byte counts to the master.
4636 config->cluster_highest_sessionid = s;
4637
4638 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4639
4640 // Do fixups into address pool.
4641 if (new->ip_pool_index != -1)
4642 fix_address_pool(s);
4643
4644 return 1;
4645 }
4646
4647 static void initplugins()
4648 {
4649 int i;
4650
4651 loaded_plugins = ll_init();
4652 // Initialize the plugins to nothing
4653 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4654 plugins[i] = ll_init();
4655 }
4656
4657 static void *open_plugin(char *plugin_name, int load)
4658 {
4659 char path[256] = "";
4660
4661 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4662 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4663 return dlopen(path, RTLD_NOW);
4664 }
4665
4666 // plugin callback to get a config value
4667 static void *getconfig(char *key, enum config_typet type)
4668 {
4669 int i;
4670
4671 for (i = 0; config_values[i].key; i++)
4672 {
4673 if (!strcmp(config_values[i].key, key))
4674 {
4675 if (config_values[i].type == type)
4676 return ((void *) config) + config_values[i].offset;
4677
4678 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4679 key, type, config_values[i].type);
4680
4681 return 0;
4682 }
4683 }
4684
4685 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4686 return 0;
4687 }
4688
4689 static int add_plugin(char *plugin_name)
4690 {
4691 static struct pluginfuncs funcs = {
4692 _log,
4693 _log_hex,
4694 fmtaddr,
4695 sessionbyuser,
4696 sessiontbysessionidt,
4697 sessionidtbysessiont,
4698 radiusnew,
4699 radiussend,
4700 getconfig,
4701 sessionshutdown,
4702 sessionkill,
4703 throttle_session,
4704 cluster_send_session,
4705 };
4706
4707 void *p = open_plugin(plugin_name, 1);
4708 int (*initfunc)(struct pluginfuncs *);
4709 int i;
4710
4711 if (!p)
4712 {
4713 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4714 return -1;
4715 }
4716
4717 if (ll_contains(loaded_plugins, p))
4718 {
4719 dlclose(p);
4720 return 0; // already loaded
4721 }
4722
4723 {
4724 int *v = dlsym(p, "plugin_api_version");
4725 if (!v || *v != PLUGIN_API_VERSION)
4726 {
4727 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4728 dlclose(p);
4729 return -1;
4730 }
4731 }
4732
4733 if ((initfunc = dlsym(p, "plugin_init")))
4734 {
4735 if (!initfunc(&funcs))
4736 {
4737 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4738 dlclose(p);
4739 return -1;
4740 }
4741 }
4742
4743 ll_push(loaded_plugins, p);
4744
4745 for (i = 0; i < max_plugin_functions; i++)
4746 {
4747 void *x;
4748 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4749 {
4750 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4751 ll_push(plugins[i], x);
4752 }
4753 }
4754
4755 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4756 return 1;
4757 }
4758
4759 static void run_plugin_done(void *plugin)
4760 {
4761 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4762
4763 if (donefunc)
4764 donefunc();
4765 }
4766
4767 static int remove_plugin(char *plugin_name)
4768 {
4769 void *p = open_plugin(plugin_name, 0);
4770 int loaded = 0;
4771
4772 if (!p)
4773 return -1;
4774
4775 if (ll_contains(loaded_plugins, p))
4776 {
4777 int i;
4778 for (i = 0; i < max_plugin_functions; i++)
4779 {
4780 void *x;
4781 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4782 ll_delete(plugins[i], x);
4783 }
4784
4785 ll_delete(loaded_plugins, p);
4786 run_plugin_done(p);
4787 loaded = 1;
4788 }
4789
4790 dlclose(p);
4791 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4792 return loaded;
4793 }
4794
4795 int run_plugins(int plugin_type, void *data)
4796 {
4797 int (*func)(void *data);
4798
4799 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4800 return PLUGIN_RET_ERROR;
4801
4802 ll_reset(plugins[plugin_type]);
4803 while ((func = ll_next(plugins[plugin_type])))
4804 {
4805 int r = func(data);
4806
4807 if (r != PLUGIN_RET_OK)
4808 return r; // stop here
4809 }
4810
4811 return PLUGIN_RET_OK;
4812 }
4813
4814 static void plugins_done()
4815 {
4816 void *p;
4817
4818 ll_reset(loaded_plugins);
4819 while ((p = ll_next(loaded_plugins)))
4820 run_plugin_done(p);
4821 }
4822
4823 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4824 {
4825 struct nsctl request;
4826 struct nsctl response;
4827 int type = unpack_control(&request, buf, len);
4828 int r;
4829 void *p;
4830
4831 if (log_stream && config->debug >= 4)
4832 {
4833 if (type < 0)
4834 {
4835 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4836 fmtaddr(addr->sin_addr.s_addr, 0), type);
4837 }
4838 else
4839 {
4840 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4841 dump_control(&request, log_stream);
4842 }
4843 }
4844
4845 switch (type)
4846 {
4847 case NSCTL_REQ_LOAD:
4848 if (request.argc != 1)
4849 {
4850 response.type = NSCTL_RES_ERR;
4851 response.argc = 1;
4852 response.argv[0] = "name of plugin required";
4853 }
4854 else if ((r = add_plugin(request.argv[0])) < 1)
4855 {
4856 response.type = NSCTL_RES_ERR;
4857 response.argc = 1;
4858 response.argv[0] = !r
4859 ? "plugin already loaded"
4860 : "error loading plugin";
4861 }
4862 else
4863 {
4864 response.type = NSCTL_RES_OK;
4865 response.argc = 0;
4866 }
4867
4868 break;
4869
4870 case NSCTL_REQ_UNLOAD:
4871 if (request.argc != 1)
4872 {
4873 response.type = NSCTL_RES_ERR;
4874 response.argc = 1;
4875 response.argv[0] = "name of plugin required";
4876 }
4877 else if ((r = remove_plugin(request.argv[0])) < 1)
4878 {
4879 response.type = NSCTL_RES_ERR;
4880 response.argc = 1;
4881 response.argv[0] = !r
4882 ? "plugin not loaded"
4883 : "plugin not found";
4884 }
4885 else
4886 {
4887 response.type = NSCTL_RES_OK;
4888 response.argc = 0;
4889 }
4890
4891 break;
4892
4893 case NSCTL_REQ_HELP:
4894 response.type = NSCTL_RES_OK;
4895 response.argc = 0;
4896
4897 ll_reset(loaded_plugins);
4898 while ((p = ll_next(loaded_plugins)))
4899 {
4900 char **help = dlsym(p, "plugin_control_help");
4901 while (response.argc < 0xff && help && *help)
4902 response.argv[response.argc++] = *help++;
4903 }
4904
4905 break;
4906
4907 case NSCTL_REQ_CONTROL:
4908 {
4909 struct param_control param = {
4910 config->cluster_iam_master,
4911 request.argc,
4912 request.argv,
4913 0,
4914 NULL,
4915 };
4916
4917 int r = run_plugins(PLUGIN_CONTROL, &param);
4918
4919 if (r == PLUGIN_RET_ERROR)
4920 {
4921 response.type = NSCTL_RES_ERR;
4922 response.argc = 1;
4923 response.argv[0] = param.additional
4924 ? param.additional
4925 : "error returned by plugin";
4926 }
4927 else if (r == PLUGIN_RET_NOTMASTER)
4928 {
4929 static char msg[] = "must be run on master: 000.000.000.000";
4930
4931 response.type = NSCTL_RES_ERR;
4932 response.argc = 1;
4933 if (config->cluster_master_address)
4934 {
4935 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4936 response.argv[0] = msg;
4937 }
4938 else
4939 {
4940 response.argv[0] = "must be run on master: none elected";
4941 }
4942 }
4943 else if (!(param.response & NSCTL_RESPONSE))
4944 {
4945 response.type = NSCTL_RES_ERR;
4946 response.argc = 1;
4947 response.argv[0] = param.response
4948 ? "unrecognised response value from plugin"
4949 : "unhandled action";
4950 }
4951 else
4952 {
4953 response.type = param.response;
4954 response.argc = 0;
4955 if (param.additional)
4956 {
4957 response.argc = 1;
4958 response.argv[0] = param.additional;
4959 }
4960 }
4961 }
4962
4963 break;
4964
4965 default:
4966 response.type = NSCTL_RES_ERR;
4967 response.argc = 1;
4968 response.argv[0] = "error unpacking control packet";
4969 }
4970
4971 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4972 if (!buf)
4973 {
4974 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4975 return;
4976 }
4977
4978 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4979 if (r > 0)
4980 {
4981 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4982 if (log_stream && config->debug >= 4)
4983 {
4984 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4985 dump_control(&response, log_stream);
4986 }
4987 }
4988 else
4989 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4990 fmtaddr(addr->sin_addr.s_addr, 0), r);
4991
4992 free(buf);
4993 }
4994
4995 static tunnelidt new_tunnel()
4996 {
4997 tunnelidt i;
4998 for (i = 1; i < MAXTUNNEL; i++)
4999 {
5000 if (tunnel[i].state == TUNNELFREE)
5001 {
5002 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
5003 if (i > config->cluster_highest_tunnelid)
5004 config->cluster_highest_tunnelid = i;
5005 return i;
5006 }
5007 }
5008 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5009 return 0;
5010 }
5011
5012 //
5013 // We're becoming the master. Do any required setup..
5014 //
5015 // This is principally telling all the plugins that we're
5016 // now a master, and telling them about all the sessions
5017 // that are active too..
5018 //
5019 void become_master(void)
5020 {
5021 int s, i;
5022 static struct event_data d[RADIUS_FDS];
5023 struct epoll_event e;
5024
5025 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5026
5027 // running a bunch of iptables commands is slow and can cause
5028 // the master to drop tunnels on takeover--kludge around the
5029 // problem by forking for the moment (note: race)
5030 if (!fork_and_close())
5031 {
5032 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5033 {
5034 if (!session[s].opened) // Not an in-use session.
5035 continue;
5036
5037 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5038 }
5039 exit(0);
5040 }
5041
5042 // add radius fds
5043 e.events = EPOLLIN;
5044 for (i = 0; i < RADIUS_FDS; i++)
5045 {
5046 d[i].type = FD_TYPE_RADIUS;
5047 d[i].index = i;
5048 e.data.ptr = &d[i];
5049
5050 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5051 }
5052 }
5053
5054 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5055 {
5056 int s, i;
5057 int count = 0;
5058 int buckets[64];
5059
5060 if (CLI_HELP_REQUESTED)
5061 return CLI_HELP_NO_ARGS;
5062
5063 time(&time_now);
5064 for (i = 0; i < 64;++i) buckets[i] = 0;
5065
5066 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5067 {
5068 int idle;
5069 if (!session[s].opened)
5070 continue;
5071
5072 idle = time_now - session[s].last_packet;
5073 idle /= 5 ; // In multiples of 5 seconds.
5074 if (idle < 0)
5075 idle = 0;
5076 if (idle > 63)
5077 idle = 63;
5078
5079 ++count;
5080 ++buckets[idle];
5081 }
5082
5083 for (i = 0; i < 63; ++i)
5084 {
5085 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5086 }
5087 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5088 cli_print(cli, "%d total sessions open.", count);
5089 return CLI_OK;
5090 }
5091
5092 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5093 {
5094 int s, i;
5095 int count = 0;
5096 int buckets[64];
5097
5098 if (CLI_HELP_REQUESTED)
5099 return CLI_HELP_NO_ARGS;
5100
5101 time(&time_now);
5102 for (i = 0; i < 64;++i) buckets[i] = 0;
5103
5104 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5105 {
5106 int open = 0, d;
5107 if (!session[s].opened)
5108 continue;
5109
5110 d = time_now - session[s].opened;
5111 if (d < 0)
5112 d = 0;
5113 while (d > 1 && open < 32)
5114 {
5115 ++open;
5116 d >>= 1; // half.
5117 }
5118 ++count;
5119 ++buckets[open];
5120 }
5121
5122 s = 1;
5123 for (i = 0; i < 30; ++i)
5124 {
5125 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5126 s <<= 1;
5127 }
5128 cli_print(cli, "%d total sessions open.", count);
5129 return CLI_OK;
5130 }
5131
5132 /* Unhide an avp.
5133 *
5134 * This unencodes the AVP using the L2TP secret and the previously
5135 * stored random vector. It overwrites the hidden data with the
5136 * unhidden AVP subformat.
5137 */
5138 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5139 {
5140 MD5_CTX ctx;
5141 uint8_t digest[16];
5142 uint8_t *last;
5143 size_t d = 0;
5144 uint16_t m = htons(type);
5145
5146 // Compute initial pad
5147 MD5_Init(&ctx);
5148 MD5_Update(&ctx, (unsigned char *) &m, 2);
5149 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5150 MD5_Update(&ctx, vector, vec_len);
5151 MD5_Final(digest, &ctx);
5152
5153 // pointer to last decoded 16 octets
5154 last = value;
5155
5156 while (len > 0)
5157 {
5158 // calculate a new pad based on the last decoded block
5159 if (d >= sizeof(digest))
5160 {
5161 MD5_Init(&ctx);
5162 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5163 MD5_Update(&ctx, last, sizeof(digest));
5164 MD5_Final(digest, &ctx);
5165
5166 d = 0;
5167 last = value;
5168 }
5169
5170 *value++ ^= digest[d++];
5171 len--;
5172 }
5173 }
5174
5175 int find_filter(char const *name, size_t len)
5176 {
5177 int free = -1;
5178 int i;
5179
5180 for (i = 0; i < MAXFILTER; i++)
5181 {
5182 if (!*ip_filters[i].name)
5183 {
5184 if (free < 0)
5185 free = i;
5186
5187 continue;
5188 }
5189
5190 if (strlen(ip_filters[i].name) != len)
5191 continue;
5192
5193 if (!strncmp(ip_filters[i].name, name, len))
5194 return i;
5195 }
5196
5197 return free;
5198 }
5199
5200 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5201 {
5202 switch (p->op)
5203 {
5204 case FILTER_PORT_OP_EQ: return port == p->port;
5205 case FILTER_PORT_OP_NEQ: return port != p->port;
5206 case FILTER_PORT_OP_GT: return port > p->port;
5207 case FILTER_PORT_OP_LT: return port < p->port;
5208 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5209 }
5210
5211 return 0;
5212 }
5213
5214 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5215 {
5216 switch (op)
5217 {
5218 case FILTER_FLAG_OP_ANY:
5219 return (flags & sflags) || (~flags & cflags);
5220
5221 case FILTER_FLAG_OP_ALL:
5222 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5223
5224 case FILTER_FLAG_OP_EST:
5225 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5226 }
5227
5228 return 0;
5229 }
5230
5231 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5232 {
5233 uint16_t frag_offset;
5234 uint8_t proto;
5235 in_addr_t src_ip;
5236 in_addr_t dst_ip;
5237 uint16_t src_port = 0;
5238 uint16_t dst_port = 0;
5239 uint8_t flags = 0;
5240 ip_filter_rulet *rule;
5241
5242 if (len < 20) // up to end of destination address
5243 return 0;
5244
5245 if ((*buf >> 4) != 4) // IPv4
5246 return 0;
5247
5248 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5249 proto = buf[9];
5250 src_ip = *(in_addr_t *) (buf + 12);
5251 dst_ip = *(in_addr_t *) (buf + 16);
5252
5253 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5254 {
5255 int l = (buf[0] & 0xf) * 4; // length of IP header
5256 if (len < l + 4) // ports
5257 return 0;
5258
5259 src_port = ntohs(*(uint16_t *) (buf + l));
5260 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5261 if (proto == IPPROTO_TCP)
5262 {
5263 if (len < l + 14) // flags
5264 return 0;
5265
5266 flags = buf[l + 13] & 0x3f;
5267 }
5268 }
5269
5270 for (rule = ip_filters[filter].rules; rule->action; rule++)
5271 {
5272 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5273 continue;
5274
5275 if (rule->src_wild != INADDR_BROADCAST &&
5276 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5277 continue;
5278
5279 if (rule->dst_wild != INADDR_BROADCAST &&
5280 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5281 continue;
5282
5283 if (frag_offset)
5284 {
5285 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5286 continue;
5287 }
5288 else
5289 {
5290 if (rule->frag)
5291 continue;
5292
5293 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5294 {
5295 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5296 continue;
5297
5298 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5299 continue;
5300
5301 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5302 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5303 continue;
5304 }
5305 }
5306
5307 // matched
5308 rule->counter++;
5309 return rule->action == FILTER_ACTION_PERMIT;
5310 }
5311
5312 // default deny
5313 return 0;
5314 }