8204503ad5ac0dfbaaf352df56351d4a7895662f
[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 1.115 2005-07-31 10:04:10 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 <openssl/md5.h>
42 #include <libcli.h>
43
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
79 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
80
81 static void *ip_hash[256]; // Mapping from IP address to session structures.
82 struct ipv6radix {
83 int sess;
84 struct ipv6radix *branch;
85 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
86
87 // Traffic counters.
88 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
89 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
90 uint32_t eth_tx = 0;
91
92 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
93 time_t time_now = 0; // Current time in seconds since epoch.
94 static char time_now_string[64] = {0}; // Current time as a string.
95 char main_quit = 0; // True if we're in the process of exiting.
96 linked_list *loaded_plugins;
97 linked_list *plugins[MAX_PLUGIN_TYPES];
98
99 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
100 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
101
102 config_descriptt config_values[] = {
103 CONFIG("debug", debug, INT),
104 CONFIG("log_file", log_filename, STRING),
105 CONFIG("pid_file", pid_file, STRING),
106 CONFIG("random_device", random_device, STRING),
107 CONFIG("l2tp_secret", l2tpsecret, STRING),
108 CONFIG("ppp_restart_time", ppp_restart_time, INT),
109 CONFIG("ppp_max_configure", ppp_max_configure, INT),
110 CONFIG("ppp_max_failure", ppp_max_failure, INT),
111 CONFIG("primary_dns", default_dns1, IPv4),
112 CONFIG("secondary_dns", default_dns2, IPv4),
113 CONFIG("primary_radius", radiusserver[0], IPv4),
114 CONFIG("secondary_radius", radiusserver[1], IPv4),
115 CONFIG("primary_radius_port", radiusport[0], SHORT),
116 CONFIG("secondary_radius_port", radiusport[1], SHORT),
117 CONFIG("radius_accounting", radius_accounting, BOOL),
118 CONFIG("radius_interim", radius_interim, INT),
119 CONFIG("radius_secret", radiussecret, STRING),
120 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
121 CONFIG("radius_dae_port", radius_dae_port, SHORT),
122 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
123 CONFIG("bind_address", bind_address, IPv4),
124 CONFIG("peer_address", peer_address, IPv4),
125 CONFIG("send_garp", send_garp, BOOL),
126 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
127 CONFIG("throttle_buckets", num_tbfs, INT),
128 CONFIG("accounting_dir", accounting_dir, STRING),
129 CONFIG("setuid", target_uid, INT),
130 CONFIG("dump_speed", dump_speed, BOOL),
131 CONFIG("multi_read_count", multi_read_count, INT),
132 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
133 CONFIG("lock_pages", lock_pages, BOOL),
134 CONFIG("icmp_rate", icmp_rate, INT),
135 CONFIG("packet_limit", max_packets, INT),
136 CONFIG("cluster_address", cluster_address, IPv4),
137 CONFIG("cluster_interface", cluster_interface, STRING),
138 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
139 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
140 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
141 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
142 { NULL, 0, 0, 0 },
143 };
144
145 static char *plugin_functions[] = {
146 NULL,
147 "plugin_pre_auth",
148 "plugin_post_auth",
149 "plugin_packet_rx",
150 "plugin_packet_tx",
151 "plugin_timer",
152 "plugin_new_session",
153 "plugin_kill_session",
154 "plugin_control",
155 "plugin_radius_response",
156 "plugin_radius_reset",
157 "plugin_become_master",
158 "plugin_new_session_master",
159 };
160
161 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
162
163 // Counters for shutdown sessions
164 static sessiont shut_acct[8192];
165 static sessionidt shut_acct_n = 0;
166
167 tunnelt *tunnel = NULL; // Array of tunnel structures.
168 sessiont *session = NULL; // Array of session structures.
169 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
170 radiust *radius = NULL; // Array of radius structures.
171 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
172 ip_filtert *ip_filters = NULL; // Array of named filters.
173 static controlt *controlfree = 0;
174 struct Tstats *_statistics = NULL;
175 #ifdef RINGBUFFER
176 struct Tringbuffer *ringbuffer = NULL;
177 #endif
178
179 static void cache_ipmap(in_addr_t ip, int s);
180 static void uncache_ipmap(in_addr_t ip);
181 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
182 static void free_ip_address(sessionidt s);
183 static void dump_acct_info(int all);
184 static void sighup_handler(int sig);
185 static void sigalrm_handler(int sig);
186 static void shutdown_handler(int sig);
187 static void sigchild_handler(int sig);
188 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
189 static void update_config(void);
190 static void read_config_file(void);
191 static void initplugins(void);
192 static int add_plugin(char *plugin_name);
193 static int remove_plugin(char *plugin_name);
194 static void plugins_done(void);
195 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
196 static tunnelidt new_tunnel(void);
197 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
198
199 // on slaves, alow BGP to withdraw cleanly before exiting
200 #define QUIT_DELAY 5
201
202 // quit actions (master)
203 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
204 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
205
206 // return internal time (10ths since process startup), set f if given
207 static clockt now(double *f)
208 {
209 struct timeval t;
210 gettimeofday(&t, 0);
211 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
212 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
213 }
214
215 // work out a retry time based on try number
216 // This is a straight bounded exponential backoff.
217 // Maximum re-try time is 32 seconds. (2^5).
218 clockt backoff(uint8_t try)
219 {
220 if (try > 5) try = 5; // max backoff
221 return now(NULL) + 10 * (1 << try);
222 }
223
224
225 //
226 // Log a debug message. Typically called via the LOG macro
227 //
228 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
229 {
230 static char message[65536] = {0};
231 va_list ap;
232
233 #ifdef RINGBUFFER
234 if (ringbuffer)
235 {
236 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
237 ringbuffer->tail = 0;
238 if (ringbuffer->tail == ringbuffer->head)
239 if (++ringbuffer->head >= RINGBUFFER_SIZE)
240 ringbuffer->head = 0;
241
242 ringbuffer->buffer[ringbuffer->tail].level = level;
243 ringbuffer->buffer[ringbuffer->tail].session = s;
244 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
245 va_start(ap, format);
246 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
247 va_end(ap);
248 }
249 #endif
250
251 if (config->debug < level) return;
252
253 va_start(ap, format);
254 vsnprintf(message, sizeof(message), format, ap);
255
256 if (log_stream)
257 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
258 else if (syslog_log)
259 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
260
261 va_end(ap);
262 }
263
264 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
265 {
266 int i, j;
267 const uint8_t *d = data;
268
269 if (config->debug < level) return;
270
271 // No support for _log_hex to syslog
272 if (log_stream)
273 {
274 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
275 setvbuf(log_stream, NULL, _IOFBF, 16384);
276
277 for (i = 0; i < maxsize; )
278 {
279 fprintf(log_stream, "%4X: ", i);
280 for (j = i; j < maxsize && j < (i + 16); j++)
281 {
282 fprintf(log_stream, "%02X ", d[j]);
283 if (j == i + 7)
284 fputs(": ", log_stream);
285 }
286
287 for (; j < i + 16; j++)
288 {
289 fputs(" ", log_stream);
290 if (j == i + 7)
291 fputs(": ", log_stream);
292 }
293
294 fputs(" ", log_stream);
295 for (j = i; j < maxsize && j < (i + 16); j++)
296 {
297 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
298 fputc(d[j], log_stream);
299 else
300 fputc('.', log_stream);
301
302 if (j == i + 7)
303 fputs(" ", log_stream);
304 }
305
306 i = j;
307 fputs("\n", log_stream);
308 }
309
310 fflush(log_stream);
311 setbuf(log_stream, NULL);
312 }
313 }
314
315 // update a counter, accumulating 2^32 wraps
316 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
317 {
318 uint32_t new = *counter + delta;
319 if (new < *counter)
320 (*wrap)++;
321
322 *counter = new;
323 }
324
325 // initialise the random generator
326 static void initrandom(char *source)
327 {
328 static char path[sizeof(config->random_device)] = "*undefined*";
329
330 // reinitialise only if we are forced to do so or if the config has changed
331 if (source && !strncmp(path, source, sizeof(path)))
332 return;
333
334 // close previous source, if any
335 if (rand_fd >= 0)
336 close(rand_fd);
337
338 rand_fd = -1;
339
340 if (source)
341 {
342 // register changes
343 snprintf(path, sizeof(path), "%s", source);
344
345 if (*path == '/')
346 {
347 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
348 if (rand_fd < 0)
349 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
350 path, strerror(errno));
351 }
352 }
353 }
354
355 // fill buffer with random data
356 void random_data(uint8_t *buf, int len)
357 {
358 int n = 0;
359
360 CSTAT(random_data);
361 if (rand_fd >= 0)
362 {
363 n = read(rand_fd, buf, len);
364 if (n >= len) return;
365 if (n < 0)
366 {
367 if (errno != EAGAIN)
368 {
369 LOG(0, 0, 0, "Error reading from random source: %s\n",
370 strerror(errno));
371
372 // fall back to rand()
373 initrandom(NULL);
374 }
375
376 n = 0;
377 }
378 }
379
380 // append missing data
381 while (n < len)
382 // not using the low order bits from the prng stream
383 buf[n++] = (rand() >> 4) & 0xff;
384 }
385
386 // Add a route
387 //
388 // This adds it to the routing table, advertises it
389 // via BGP if enabled, and stuffs it into the
390 // 'sessionbyip' cache.
391 //
392 // 'ip' and 'mask' must be in _host_ order.
393 //
394 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
395 {
396 struct rtentry r;
397 int i;
398
399 if (!mask) mask = 0xffffffff;
400
401 ip &= mask; // Force the ip to be the first one in the route.
402
403 memset(&r, 0, sizeof(r));
404 r.rt_dev = config->tundevice;
405 r.rt_dst.sa_family = AF_INET;
406 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
407 r.rt_gateway.sa_family = AF_INET;
408 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
409 r.rt_genmask.sa_family = AF_INET;
410 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
411 r.rt_flags = (RTF_UP | RTF_STATIC);
412 if (gw)
413 r.rt_flags |= RTF_GATEWAY;
414 else if (mask == 0xffffffff)
415 r.rt_flags |= RTF_HOST;
416
417 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
418 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
419 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
420
421 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
422 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
423
424 #ifdef BGP
425 if (add)
426 bgp_add_route(htonl(ip), htonl(mask));
427 else
428 bgp_del_route(htonl(ip), htonl(mask));
429 #endif /* BGP */
430
431 // Add/Remove the IPs to the 'sessionbyip' cache.
432 // Note that we add the zero address in the case of
433 // a network route. Roll on CIDR.
434
435 // Note that 's == 0' implies this is the address pool.
436 // We still cache it here, because it will pre-fill
437 // the malloc'ed tree.
438
439 if (s)
440 {
441 if (!add) // Are we deleting a route?
442 s = 0; // Caching the session as '0' is the same as uncaching.
443
444 for (i = ip; (i&mask) == (ip&mask) ; ++i)
445 cache_ipmap(i, s);
446 }
447 }
448
449 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
450 {
451 struct in6_rtmsg rt;
452 char ipv6addr[INET6_ADDRSTRLEN];
453
454 if (ifr6fd < 0)
455 {
456 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
457 return;
458 }
459
460 memset(&rt, 0, sizeof(rt));
461
462 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
463 rt.rtmsg_dst_len = prefixlen;
464 rt.rtmsg_metric = 1;
465 rt.rtmsg_flags = RTF_UP;
466 rt.rtmsg_ifindex = tunidx;
467
468 LOG(1, 0, 0, "Route %s %s/%d\n",
469 add ? "add" : "del",
470 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
471 prefixlen);
472
473 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
474 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
475 strerror(errno));
476
477 // FIXME: need to add BGP routing (RFC2858)
478
479 if (s)
480 {
481 if (!add) // Are we deleting a route?
482 s = 0; // Caching the session as '0' is the same as uncaching.
483
484 cache_ipv6map(ip, prefixlen, s);
485 }
486
487 return;
488 }
489
490 // defined in linux/ipv6.h, but tricky to include from user-space
491 // TODO: move routing to use netlink rather than ioctl
492 struct in6_ifreq {
493 struct in6_addr ifr6_addr;
494 __u32 ifr6_prefixlen;
495 unsigned int ifr6_ifindex;
496 };
497
498 //
499 // Set up TUN interface
500 static void inittun(void)
501 {
502 struct ifreq ifr;
503 struct in6_ifreq ifr6;
504 struct sockaddr_in sin = {0};
505 memset(&ifr, 0, sizeof(ifr));
506 ifr.ifr_flags = IFF_TUN;
507
508 tunfd = open(TUNDEVICE, O_RDWR);
509 if (tunfd < 0)
510 { // fatal
511 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
512 exit(1);
513 }
514 {
515 int flags = fcntl(tunfd, F_GETFL, 0);
516 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
517 }
518 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
519 {
520 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
521 exit(1);
522 }
523 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
524 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
525 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
526
527 sin.sin_family = AF_INET;
528 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
529 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
530
531 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
532 {
533 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
534 exit(1);
535 }
536 /* Bump up the qlen to deal with bursts from the network */
537 ifr.ifr_qlen = 1000;
538 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
539 {
540 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
541 exit(1);
542 }
543 ifr.ifr_flags = IFF_UP;
544 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
545 {
546 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
547 exit(1);
548 }
549 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
550 {
551 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
552 exit(1);
553 }
554 tunidx = ifr.ifr_ifindex;
555
556 // Only setup IPv6 on the tun device if we have a configured prefix
557 if (config->ipv6_prefix.s6_addr[0]) {
558 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
559
560 // Link local address is FE80::1
561 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
562 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
563 ifr6.ifr6_addr.s6_addr[1] = 0x80;
564 ifr6.ifr6_addr.s6_addr[15] = 1;
565 ifr6.ifr6_prefixlen = 64;
566 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
567 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
568 {
569 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
570 " %s\n", strerror(errno));
571 }
572
573 // Global address is prefix::1
574 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
575 ifr6.ifr6_addr = config->ipv6_prefix;
576 ifr6.ifr6_addr.s6_addr[15] = 1;
577 ifr6.ifr6_prefixlen = 64;
578 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
579 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
580 {
581 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
582 strerror(errno));
583 }
584 }
585 }
586
587 // set up UDP ports
588 static void initudp(void)
589 {
590 int on = 1;
591 struct sockaddr_in addr;
592
593 // Tunnel
594 memset(&addr, 0, sizeof(addr));
595 addr.sin_family = AF_INET;
596 addr.sin_port = htons(L2TPPORT);
597 addr.sin_addr.s_addr = config->bind_address;
598 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
599 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
600 {
601 int flags = fcntl(udpfd, F_GETFL, 0);
602 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
603 }
604 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
605 {
606 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
607 exit(1);
608 }
609
610 // Control
611 memset(&addr, 0, sizeof(addr));
612 addr.sin_family = AF_INET;
613 addr.sin_port = htons(NSCTL_PORT);
614 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
615 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
616 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
617 {
618 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
619 exit(1);
620 }
621
622 // Dynamic Authorization Extensions to RADIUS
623 memset(&addr, 0, sizeof(addr));
624 addr.sin_family = AF_INET;
625 addr.sin_port = htons(config->radius_dae_port);
626 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
627 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
628 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
629 {
630 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
631 exit(1);
632 }
633
634 // Intercept
635 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
636 }
637
638 //
639 // Find session by IP, < 1 for not found
640 //
641 // Confusingly enough, this 'ip' must be
642 // in _network_ order. This being the common
643 // case when looking it up from IP packet headers.
644 //
645 // We actually use this cache for two things.
646 // #1. For used IP addresses, this maps to the
647 // session ID that it's used by.
648 // #2. For un-used IP addresses, this maps to the
649 // index into the pool table that contains that
650 // IP address.
651 //
652
653 static int lookup_ipmap(in_addr_t ip)
654 {
655 uint8_t *a = (uint8_t *) &ip;
656 uint8_t **d = (uint8_t **) ip_hash;
657
658 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
659 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
660 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
661
662 return (int) (intptr_t) d[(size_t) *a];
663 }
664
665 static int lookup_ipv6map(struct in6_addr ip)
666 {
667 struct ipv6radix *curnode;
668 int i;
669 int s;
670 char ipv6addr[INET6_ADDRSTRLEN];
671
672 curnode = &ipv6_hash[ip.s6_addr[0]];
673 i = 1;
674 s = curnode->sess;
675
676 while (s == 0 && i < 15 && curnode->branch != NULL)
677 {
678 curnode = &curnode->branch[ip.s6_addr[i]];
679 s = curnode->sess;
680 i++;
681 }
682
683 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
684 inet_ntop(AF_INET6, &ip, ipv6addr,
685 INET6_ADDRSTRLEN),
686 s);
687
688 return s;
689 }
690
691 sessionidt sessionbyip(in_addr_t ip)
692 {
693 int s = lookup_ipmap(ip);
694 CSTAT(sessionbyip);
695
696 if (s > 0 && s < MAXSESSION && session[s].opened)
697 return (sessionidt) s;
698
699 return 0;
700 }
701
702 sessionidt sessionbyipv6(struct in6_addr ip)
703 {
704 int s;
705 CSTAT(sessionbyipv6);
706
707 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
708 (ip.s6_addr[0] == 0xFE &&
709 ip.s6_addr[1] == 0x80 &&
710 ip.s6_addr16[1] == 0 &&
711 ip.s6_addr16[2] == 0 &&
712 ip.s6_addr16[3] == 0)) {
713 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
714 } else {
715 s = lookup_ipv6map(ip);
716 }
717
718 if (s > 0 && s < MAXSESSION && session[s].opened)
719 return s;
720
721 return 0;
722 }
723
724 //
725 // Take an IP address in HOST byte order and
726 // add it to the sessionid by IP cache.
727 //
728 // (It's actually cached in network order)
729 //
730 static void cache_ipmap(in_addr_t ip, int s)
731 {
732 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
733 uint8_t *a = (uint8_t *) &nip;
734 uint8_t **d = (uint8_t **) ip_hash;
735 int i;
736
737 for (i = 0; i < 3; i++)
738 {
739 if (!d[(size_t) a[i]])
740 {
741 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
742 return;
743 }
744
745 d = (uint8_t **) d[(size_t) a[i]];
746 }
747
748 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
749
750 if (s > 0)
751 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
752
753 else if (s == 0)
754 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
755 // else a map to an ip pool index.
756 }
757
758 static void uncache_ipmap(in_addr_t ip)
759 {
760 cache_ipmap(ip, 0); // Assign it to the NULL session.
761 }
762
763 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
764 {
765 int i;
766 int bytes;
767 struct ipv6radix *curnode;
768 char ipv6addr[INET6_ADDRSTRLEN];
769
770 curnode = &ipv6_hash[ip.s6_addr[0]];
771
772 bytes = prefixlen >> 3;
773 i = 1;
774 while (i < bytes) {
775 if (curnode->branch == NULL)
776 {
777 if (!(curnode->branch = calloc(256,
778 sizeof (struct ipv6radix))))
779 return;
780 }
781 curnode = &curnode->branch[ip.s6_addr[i]];
782 i++;
783 }
784
785 curnode->sess = s;
786
787 if (s > 0)
788 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
789 inet_ntop(AF_INET6, &ip, ipv6addr,
790 INET6_ADDRSTRLEN),
791 prefixlen);
792 else if (s == 0)
793 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
794 inet_ntop(AF_INET6, &ip, ipv6addr,
795 INET6_ADDRSTRLEN),
796 prefixlen);
797 }
798
799 //
800 // CLI list to dump current ipcache.
801 //
802 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
803 {
804 char **d = (char **) ip_hash, **e, **f, **g;
805 int i, j, k, l;
806 int count = 0;
807
808 if (CLI_HELP_REQUESTED)
809 return CLI_HELP_NO_ARGS;
810
811 cli_print(cli, "%7s %s", "Sess#", "IP Address");
812
813 for (i = 0; i < 256; ++i)
814 {
815 if (!d[i])
816 continue;
817 e = (char **) d[i];
818 for (j = 0; j < 256; ++j)
819 {
820 if (!e[j])
821 continue;
822 f = (char **) e[j];
823 for (k = 0; k < 256; ++k)
824 {
825 if (!f[k])
826 continue;
827 g = (char **)f[k];
828 for (l = 0; l < 256; ++l)
829 {
830 if (!g[l])
831 continue;
832 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
833 ++count;
834 }
835 }
836 }
837 }
838 cli_print(cli, "%d entries in cache", count);
839 return CLI_OK;
840 }
841
842
843 // Find session by username, 0 for not found
844 // walled garden users aren't authenticated, so the username is
845 // reasonably useless. Ignore them to avoid incorrect actions
846 //
847 // This is VERY inefficent. Don't call it often. :)
848 //
849 sessionidt sessionbyuser(char *username)
850 {
851 int s;
852 CSTAT(sessionbyuser);
853
854 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
855 {
856 if (!session[s].opened)
857 continue;
858
859 if (session[s].walled_garden)
860 continue; // Skip walled garden users.
861
862 if (!strncmp(session[s].user, username, 128))
863 return s;
864
865 }
866 return 0; // Not found.
867 }
868
869 void send_garp(in_addr_t ip)
870 {
871 int s;
872 struct ifreq ifr;
873 uint8_t mac[6];
874
875 s = socket(PF_INET, SOCK_DGRAM, 0);
876 if (s < 0)
877 {
878 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
879 return;
880 }
881 memset(&ifr, 0, sizeof(ifr));
882 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
883 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
884 {
885 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
886 close(s);
887 return;
888 }
889 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
890 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
891 {
892 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
893 close(s);
894 return;
895 }
896 close(s);
897 sendarp(ifr.ifr_ifindex, mac, ip);
898 }
899
900 static sessiont *sessiontbysessionidt(sessionidt s)
901 {
902 if (!s || s >= MAXSESSION) return NULL;
903 return &session[s];
904 }
905
906 static sessionidt sessionidtbysessiont(sessiont *s)
907 {
908 sessionidt val = s-session;
909 if (s < session || val >= MAXSESSION) return 0;
910 return val;
911 }
912
913 // actually send a control message for a specific tunnel
914 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
915 {
916 struct sockaddr_in addr;
917
918 CSTAT(tunnelsend);
919
920 if (!t)
921 {
922 static int backtrace_count = 0;
923 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
924 STAT(tunnel_tx_errors);
925 log_backtrace(backtrace_count, 5)
926 return;
927 }
928
929 if (!tunnel[t].ip)
930 {
931 static int backtrace_count = 0;
932 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
933 log_backtrace(backtrace_count, 5)
934 STAT(tunnel_tx_errors);
935 return;
936 }
937
938 memset(&addr, 0, sizeof(addr));
939 addr.sin_family = AF_INET;
940 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
941 addr.sin_port = htons(tunnel[t].port);
942
943 // sequence expected, if sequence in message
944 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
945
946 // If this is a control message, deal with retries
947 if (*buf & 0x80)
948 {
949 tunnel[t].last = time_now; // control message sent
950 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
951 if (tunnel[t].try > 1)
952 {
953 STAT(tunnel_retries);
954 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
955 }
956 }
957
958 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
959 {
960 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
961 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
962 STAT(tunnel_tx_errors);
963 return;
964 }
965
966 LOG_HEX(5, "Send Tunnel Data", buf, l);
967 STAT(tunnel_tx_packets);
968 INC_STAT(tunnel_tx_bytes, l);
969 }
970
971 //
972 // Tiny helper function to write data to
973 // the 'tun' device.
974 //
975 int tun_write(uint8_t * data, int size)
976 {
977 return write(tunfd, data, size);
978 }
979
980 // process outgoing (to tunnel) IP
981 //
982 static void processipout(uint8_t *buf, int len)
983 {
984 sessionidt s;
985 sessiont *sp;
986 tunnelidt t;
987 in_addr_t ip;
988
989 uint8_t *data = buf; // Keep a copy of the originals.
990 int size = len;
991
992 uint8_t b[MAXETHER + 20];
993
994 CSTAT(processipout);
995
996 if (len < MIN_IP_SIZE)
997 {
998 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
999 STAT(tun_rx_errors);
1000 return;
1001 }
1002 if (len >= MAXETHER)
1003 {
1004 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1005 STAT(tun_rx_errors);
1006 return;
1007 }
1008
1009 // Skip the tun header
1010 buf += 4;
1011 len -= 4;
1012
1013 // Got an IP header now
1014 if (*(uint8_t *)(buf) >> 4 != 4)
1015 {
1016 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1017 return;
1018 }
1019
1020 ip = *(uint32_t *)(buf + 16);
1021 if (!(s = sessionbyip(ip)))
1022 {
1023 // Is this a packet for a session that doesn't exist?
1024 static int rate = 0; // Number of ICMP packets we've sent this second.
1025 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1026
1027 if (last != time_now)
1028 {
1029 last = time_now;
1030 rate = 0;
1031 }
1032
1033 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1034 {
1035 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1036 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1037 config->bind_address ? config->bind_address : my_address, buf, len);
1038 }
1039 return;
1040 }
1041 t = session[s].tunnel;
1042 sp = &session[s];
1043
1044 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1045 if (config->max_packets > 0)
1046 {
1047 if (sess_local[s].last_packet_out == TIME)
1048 {
1049 int max = config->max_packets;
1050
1051 // All packets for throttled sessions are handled by the
1052 // master, so further limit by using the throttle rate.
1053 // A bit of a kludge, since throttle rate is in kbps,
1054 // but should still be generous given our average DSL
1055 // packet size is 200 bytes: a limit of 28kbps equates
1056 // to around 180 packets per second.
1057 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1058 max = sp->throttle_out;
1059
1060 if (++sess_local[s].packets_out > max)
1061 {
1062 sess_local[s].packets_dropped++;
1063 return;
1064 }
1065 }
1066 else
1067 {
1068 if (sess_local[s].packets_dropped)
1069 {
1070 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1071 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1072 sess_local[s].packets_dropped, sess_local[s].packets_out,
1073 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1074 sp->user);
1075 }
1076
1077 sess_local[s].last_packet_out = TIME;
1078 sess_local[s].packets_out = 1;
1079 sess_local[s].packets_dropped = 0;
1080 }
1081 }
1082
1083 // run access-list if any
1084 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1085 return;
1086
1087 if (sp->tbf_out)
1088 {
1089 // Are we throttling this session?
1090 if (config->cluster_iam_master)
1091 tbf_queue_packet(sp->tbf_out, data, size);
1092 else
1093 master_throttle_packet(sp->tbf_out, data, size);
1094 return;
1095 }
1096 else if (sp->walled_garden && !config->cluster_iam_master)
1097 {
1098 // We are walled-gardening this
1099 master_garden_packet(s, data, size);
1100 return;
1101 }
1102
1103 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1104
1105 // Add on L2TP header
1106 {
1107 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1108 if (!p) return;
1109 tunnelsend(b, len + (p-b), t); // send it...
1110 }
1111
1112 // Snooping this session, send it to intercept box
1113 if (sp->snoop_ip && sp->snoop_port)
1114 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1115
1116 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1117 sp->cout_delta += len;
1118 sp->pout++;
1119 udp_tx += len;
1120
1121 sess_local[s].cout += len; // To send to master..
1122 sess_local[s].pout++;
1123 }
1124
1125 // process outgoing (to tunnel) IPv6
1126 //
1127 static void processipv6out(uint8_t * buf, int len)
1128 {
1129 sessionidt s;
1130 sessiont *sp;
1131 tunnelidt t;
1132 in_addr_t ip;
1133 struct in6_addr ip6;
1134
1135 uint8_t *data = buf; // Keep a copy of the originals.
1136 int size = len;
1137
1138 uint8_t b[MAXETHER + 20];
1139
1140 CSTAT(processipv6out);
1141
1142 if (len < MIN_IP_SIZE)
1143 {
1144 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1145 STAT(tunnel_tx_errors);
1146 return;
1147 }
1148 if (len >= MAXETHER)
1149 {
1150 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1151 STAT(tunnel_tx_errors);
1152 return;
1153 }
1154
1155 // Skip the tun header
1156 buf += 4;
1157 len -= 4;
1158
1159 // Got an IP header now
1160 if (*(uint8_t *)(buf) >> 4 != 6)
1161 {
1162 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1163 return;
1164 }
1165
1166 ip6 = *(struct in6_addr *)(buf+24);
1167 s = sessionbyipv6(ip6);
1168
1169 if (s == 0)
1170 {
1171 ip = *(uint32_t *)(buf + 32);
1172 s = sessionbyip(ip);
1173 }
1174
1175 if (s == 0)
1176 {
1177 // Is this a packet for a session that doesn't exist?
1178 static int rate = 0; // Number of ICMP packets we've sent this second.
1179 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1180
1181 if (last != time_now)
1182 {
1183 last = time_now;
1184 rate = 0;
1185 }
1186
1187 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1188 {
1189 // FIXME: Should send icmp6 host unreachable
1190 }
1191 return;
1192 }
1193 t = session[s].tunnel;
1194 sp = &session[s];
1195
1196 // FIXME: add DoS prevention/filters?
1197
1198 if (sp->tbf_out)
1199 {
1200 // Are we throttling this session?
1201 if (config->cluster_iam_master)
1202 tbf_queue_packet(sp->tbf_out, data, size);
1203 else
1204 master_throttle_packet(sp->tbf_out, data, size);
1205 return;
1206 }
1207 else if (sp->walled_garden && !config->cluster_iam_master)
1208 {
1209 // We are walled-gardening this
1210 master_garden_packet(s, data, size);
1211 return;
1212 }
1213
1214 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1215
1216 // Add on L2TP header
1217 {
1218 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIPV6);
1219 if (!p) return;
1220 tunnelsend(b, len + (p-b), t); // send it...
1221 }
1222
1223 // Snooping this session, send it to intercept box
1224 if (sp->snoop_ip && sp->snoop_port)
1225 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1226
1227 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1228 sp->cout_delta += len;
1229 sp->pout++;
1230 udp_tx += len;
1231
1232 sess_local[s].cout += len; // To send to master..
1233 sess_local[s].pout++;
1234 }
1235
1236 //
1237 // Helper routine for the TBF filters.
1238 // Used to send queued data in to the user!
1239 //
1240 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1241 {
1242 sessiont *sp;
1243 tunnelidt t;
1244 in_addr_t ip;
1245
1246 uint8_t b[MAXETHER + 20];
1247
1248 if (len < 0 || len > MAXETHER)
1249 {
1250 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1251 return;
1252 }
1253
1254 // Skip the tun header
1255 buf += 4;
1256 len -= 4;
1257
1258 ip = *(in_addr_t *)(buf + 16);
1259
1260 if (!session[s].ip)
1261 return;
1262
1263 t = session[s].tunnel;
1264 sp = &session[s];
1265
1266 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1267
1268 // Add on L2TP header
1269 {
1270 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1271 if (!p) return;
1272 tunnelsend(b, len + (p-b), t); // send it...
1273 }
1274
1275 // Snooping this session.
1276 if (sp->snoop_ip && sp->snoop_port)
1277 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1278
1279 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1280 sp->cout_delta += len;
1281 sp->pout++;
1282 udp_tx += len;
1283
1284 sess_local[s].cout += len; // To send to master..
1285 sess_local[s].pout++;
1286 }
1287
1288 // add an AVP (16 bit)
1289 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1290 {
1291 uint16_t l = (m ? 0x8008 : 0x0008);
1292 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1293 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1294 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1295 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1296 c->length += 8;
1297 }
1298
1299 // add an AVP (32 bit)
1300 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1301 {
1302 uint16_t l = (m ? 0x800A : 0x000A);
1303 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1304 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1305 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1306 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1307 c->length += 10;
1308 }
1309
1310 // add an AVP (string)
1311 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1312 {
1313 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1314 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1315 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1316 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1317 memcpy(c->buf + c->length + 6, val, strlen(val));
1318 c->length += 6 + strlen(val);
1319 }
1320
1321 // add a binary AVP
1322 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1323 {
1324 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1325 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1326 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1327 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1328 memcpy(c->buf + c->length + 6, val, len);
1329 c->length += 6 + len;
1330 }
1331
1332 // new control connection
1333 static controlt *controlnew(uint16_t mtype)
1334 {
1335 controlt *c;
1336 if (!controlfree)
1337 c = malloc(sizeof(controlt));
1338 else
1339 {
1340 c = controlfree;
1341 controlfree = c->next;
1342 }
1343 assert(c);
1344 c->next = 0;
1345 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1346 c->length = 12;
1347 control16(c, 0, mtype, 1);
1348 return c;
1349 }
1350
1351 // send zero block if nothing is waiting
1352 // (ZLB send).
1353 static void controlnull(tunnelidt t)
1354 {
1355 uint8_t buf[12];
1356 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1357 return;
1358
1359 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1360 *(uint16_t *) (buf + 2) = htons(12); // length
1361 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1362 *(uint16_t *) (buf + 6) = htons(0); // session
1363 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1364 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1365 tunnelsend(buf, 12, t);
1366 }
1367
1368 // add a control message to a tunnel, and send if within window
1369 static void controladd(controlt * c, tunnelidt t, sessionidt far)
1370 {
1371 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1372 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1373 *(uint16_t *) (c->buf + 6) = htons(far); // session
1374 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1375 tunnel[t].ns++; // advance sequence
1376 // link in message in to queue
1377 if (tunnel[t].controlc)
1378 tunnel[t].controle->next = c;
1379 else
1380 tunnel[t].controls = c;
1381
1382 tunnel[t].controle = c;
1383 tunnel[t].controlc++;
1384
1385 // send now if space in window
1386 if (tunnel[t].controlc <= tunnel[t].window)
1387 {
1388 tunnel[t].try = 0; // first send
1389 tunnelsend(c->buf, c->length, t);
1390 }
1391 }
1392
1393 //
1394 // Throttle or Unthrottle a session
1395 //
1396 // Throttle the data from/to through a session to no more than
1397 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1398 // user).
1399 //
1400 // If either value is -1, the current value is retained for that
1401 // direction.
1402 //
1403 void throttle_session(sessionidt s, int rate_in, int rate_out)
1404 {
1405 if (!session[s].opened)
1406 return; // No-one home.
1407
1408 if (!*session[s].user)
1409 return; // User not logged in
1410
1411 if (rate_in >= 0)
1412 {
1413 int bytes = rate_in * 1024 / 8; // kbits to bytes
1414 if (session[s].tbf_in)
1415 free_tbf(session[s].tbf_in);
1416
1417 if (rate_in > 0)
1418 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1419 else
1420 session[s].tbf_in = 0;
1421
1422 session[s].throttle_in = rate_in;
1423 }
1424
1425 if (rate_out >= 0)
1426 {
1427 int bytes = rate_out * 1024 / 8;
1428 if (session[s].tbf_out)
1429 free_tbf(session[s].tbf_out);
1430
1431 if (rate_out > 0)
1432 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1433 else
1434 session[s].tbf_out = 0;
1435
1436 session[s].throttle_out = rate_out;
1437 }
1438 }
1439
1440 // add/remove filters from session (-1 = no change)
1441 void filter_session(sessionidt s, int filter_in, int filter_out)
1442 {
1443 if (!session[s].opened)
1444 return; // No-one home.
1445
1446 if (!*session[s].user)
1447 return; // User not logged in
1448
1449 // paranoia
1450 if (filter_in > MAXFILTER) filter_in = -1;
1451 if (filter_out > MAXFILTER) filter_out = -1;
1452 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1453 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1454
1455 if (filter_in >= 0)
1456 {
1457 if (session[s].filter_in)
1458 ip_filters[session[s].filter_in - 1].used--;
1459
1460 if (filter_in > 0)
1461 ip_filters[filter_in - 1].used++;
1462
1463 session[s].filter_in = filter_in;
1464 }
1465
1466 if (filter_out >= 0)
1467 {
1468 if (session[s].filter_out)
1469 ip_filters[session[s].filter_out - 1].used--;
1470
1471 if (filter_out > 0)
1472 ip_filters[filter_out - 1].used++;
1473
1474 session[s].filter_out = filter_out;
1475 }
1476 }
1477
1478 // start tidy shutdown of session
1479 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1480 {
1481 int walled_garden = session[s].walled_garden;
1482
1483
1484 CSTAT(sessionshutdown);
1485
1486 if (!session[s].opened)
1487 {
1488 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1489 return; // not a live session
1490 }
1491
1492 if (!session[s].die)
1493 {
1494 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1495 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1496 run_plugins(PLUGIN_KILL_SESSION, &data);
1497 }
1498
1499 if (session[s].ip && !walled_garden && !session[s].die)
1500 {
1501 // RADIUS Stop message
1502 uint16_t r = radiusnew(s);
1503 if (r)
1504 {
1505 // stop, if not already trying
1506 if (radius[r].state != RADIUSSTOP)
1507 radiussend(r, RADIUSSTOP);
1508 }
1509 else
1510 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1511
1512 // Save counters to dump to accounting file
1513 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1514 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1515 }
1516
1517 if (session[s].ip)
1518 { // IP allocated, clear and unroute
1519 int r;
1520 int routed = 0;
1521 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1522 {
1523 if ((session[s].ip & session[s].route[r].mask) ==
1524 (session[s].route[r].ip & session[s].route[r].mask))
1525 routed++;
1526
1527 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1528 session[s].route[r].ip = 0;
1529 }
1530
1531 if (session[s].ip_pool_index == -1) // static ip
1532 {
1533 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1534 session[s].ip = 0;
1535 }
1536 else
1537 free_ip_address(s);
1538
1539 // unroute IPv6, if setup
1540 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1541 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1542 }
1543
1544 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1545 throttle_session(s, 0, 0);
1546
1547 if (result)
1548 { // Send CDN
1549 controlt *c = controlnew(14); // sending CDN
1550 if (error)
1551 {
1552 uint8_t buf[4];
1553 *(uint16_t *) buf = htons(result);
1554 *(uint16_t *) (buf+2) = htons(error);
1555 controlb(c, 1, buf, 4, 1);
1556 }
1557 else
1558 control16(c, 1, result, 1);
1559
1560 control16(c, 14, s, 1); // assigned session (our end)
1561 controladd(c, session[s].tunnel, session[s].far); // send the message
1562 }
1563
1564 if (!session[s].die)
1565 session[s].die = TIME + 150; // Clean up in 15 seconds
1566
1567 // update filter refcounts
1568 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1569 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1570
1571 // clear PPP state
1572 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1573 sess_local[s].lcp.restart = 0;
1574 sess_local[s].ipcp.restart = 0;
1575 sess_local[s].ipv6cp.restart = 0;
1576 sess_local[s].ccp.restart = 0;
1577
1578 cluster_send_session(s);
1579 }
1580
1581 void sendipcp(tunnelidt t, sessionidt s)
1582 {
1583 uint8_t buf[MAXCONTROL];
1584 uint8_t *q;
1585
1586 CSTAT(sendipcp);
1587
1588 if (!session[s].unique_id)
1589 {
1590 if (!++last_id) ++last_id; // skip zero
1591 session[s].unique_id = last_id;
1592 }
1593
1594 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1595 if (!q) return;
1596
1597 *q = ConfigReq;
1598 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1599 *(uint16_t *) (q + 2) = htons(10); // packet length
1600 q[4] = 3; // ip address option
1601 q[5] = 6; // option length
1602 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1603 config->bind_address ? config->bind_address :
1604 my_address; // send my IP
1605
1606 tunnelsend(buf, 10 + (q - buf), t); // send it
1607 }
1608
1609 void sendipv6cp(tunnelidt t, sessionidt s)
1610 {
1611 uint8_t buf[MAXCONTROL];
1612 uint8_t *q;
1613
1614 CSTAT(sendipv6cp);
1615
1616 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
1617 if (!q) return;
1618
1619 *q = ConfigReq;
1620 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1621 // only send one type
1622 // of request
1623 *(uint16_t *) (q + 2) = htons(14);
1624 q[4] = 1; // interface identifier option
1625 q[5] = 10; // option length
1626 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1627 *(uint32_t *) (q + 10) = 0;
1628 q[13] = 1;
1629
1630 tunnelsend(buf, 14 + (q - buf), t); // send it
1631 }
1632
1633 static void sessionclear(sessionidt s)
1634 {
1635 memset(&session[s], 0, sizeof(session[s]));
1636 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1637 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1638
1639 session[s].tunnel = T_FREE; // Mark it as free.
1640 session[s].next = sessionfree;
1641 sessionfree = s;
1642 }
1643
1644 // kill a session now
1645 void sessionkill(sessionidt s, char *reason)
1646 {
1647
1648 CSTAT(sessionkill);
1649
1650 if (!session[s].opened) // not alive
1651 return;
1652
1653 if (session[s].next)
1654 {
1655 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1656 return;
1657 }
1658
1659 session[s].die = TIME;
1660 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1661 if (sess_local[s].radius)
1662 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1663
1664 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1665 sessionclear(s);
1666 cluster_send_session(s);
1667 }
1668
1669 static void tunnelclear(tunnelidt t)
1670 {
1671 if (!t) return;
1672 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1673 tunnel[t].state = TUNNELFREE;
1674 }
1675
1676 // kill a tunnel now
1677 static void tunnelkill(tunnelidt t, char *reason)
1678 {
1679 sessionidt s;
1680 controlt *c;
1681
1682 CSTAT(tunnelkill);
1683
1684 tunnel[t].state = TUNNELDIE;
1685
1686 // free control messages
1687 while ((c = tunnel[t].controls))
1688 {
1689 controlt * n = c->next;
1690 tunnel[t].controls = n;
1691 tunnel[t].controlc--;
1692 c->next = controlfree;
1693 controlfree = c;
1694 }
1695 // kill sessions
1696 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1697 if (session[s].tunnel == t)
1698 sessionkill(s, reason);
1699
1700 // free tunnel
1701 tunnelclear(t);
1702 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1703 cli_tunnel_actions[t].action = 0;
1704 cluster_send_tunnel(t);
1705 }
1706
1707 // shut down a tunnel cleanly
1708 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1709 {
1710 sessionidt s;
1711
1712 CSTAT(tunnelshutdown);
1713
1714 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1715 {
1716 // never set up, can immediately kill
1717 tunnelkill(t, reason);
1718 return;
1719 }
1720 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1721
1722 // close session
1723 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1724 if (session[s].tunnel == t)
1725 sessionshutdown(s, reason, 0, 0);
1726
1727 tunnel[t].state = TUNNELDIE;
1728 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1729 cluster_send_tunnel(t);
1730 // TBA - should we wait for sessions to stop?
1731 if (result)
1732 {
1733 controlt *c = controlnew(4); // sending StopCCN
1734 if (error)
1735 {
1736 uint8_t buf[64];
1737 int l = 4;
1738 *(uint16_t *) buf = htons(result);
1739 *(uint16_t *) (buf+2) = htons(error);
1740 if (msg)
1741 {
1742 int m = strlen(msg);
1743 if (m + 4 > sizeof(buf))
1744 m = sizeof(buf) - 4;
1745
1746 memcpy(buf+4, msg, m);
1747 l += m;
1748 }
1749
1750 controlb(c, 1, buf, l, 1);
1751 }
1752 else
1753 control16(c, 1, result, 1);
1754
1755 control16(c, 9, t, 1); // assigned tunnel (our end)
1756 controladd(c, t, 0); // send the message
1757 }
1758 }
1759
1760 // read and process packet on tunnel (UDP)
1761 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1762 {
1763 uint8_t *chapresponse = NULL;
1764 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1765 uint8_t *p = buf + 2;
1766
1767
1768 CSTAT(processudp);
1769
1770 udp_rx += len;
1771 udp_rx_pkt++;
1772 LOG_HEX(5, "UDP Data", buf, len);
1773 STAT(tunnel_rx_packets);
1774 INC_STAT(tunnel_rx_bytes, len);
1775 if (len < 6)
1776 {
1777 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1778 STAT(tunnel_rx_errors);
1779 return;
1780 }
1781 if ((buf[1] & 0x0F) != 2)
1782 {
1783 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1784 STAT(tunnel_rx_errors);
1785 return;
1786 }
1787 if (*buf & 0x40)
1788 { // length
1789 l = ntohs(*(uint16_t *) p);
1790 p += 2;
1791 }
1792 t = ntohs(*(uint16_t *) p);
1793 p += 2;
1794 s = ntohs(*(uint16_t *) p);
1795 p += 2;
1796 if (s >= MAXSESSION)
1797 {
1798 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1799 STAT(tunnel_rx_errors);
1800 return;
1801 }
1802 if (t >= MAXTUNNEL)
1803 {
1804 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1805 STAT(tunnel_rx_errors);
1806 return;
1807 }
1808 if (*buf & 0x08)
1809 { // ns/nr
1810 ns = ntohs(*(uint16_t *) p);
1811 p += 2;
1812 nr = ntohs(*(uint16_t *) p);
1813 p += 2;
1814 }
1815 if (*buf & 0x02)
1816 { // offset
1817 uint16_t o = ntohs(*(uint16_t *) p);
1818 p += o + 2;
1819 }
1820 if ((p - buf) > l)
1821 {
1822 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1823 STAT(tunnel_rx_errors);
1824 return;
1825 }
1826 l -= (p - buf);
1827 if (*buf & 0x80)
1828 { // control
1829 uint16_t message = 0xFFFF; // message type
1830 uint8_t fatal = 0;
1831 uint8_t mandatory = 0;
1832 uint8_t authtype = 0; // proxy auth type
1833 uint16_t asession = 0; // assigned session
1834 uint32_t amagic = 0; // magic number
1835 uint8_t aflags = 0; // flags from last LCF
1836 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1837 char called[MAXTEL] = ""; // called number
1838 char calling[MAXTEL] = ""; // calling number
1839
1840 if (!config->cluster_iam_master)
1841 {
1842 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1843 return;
1844 }
1845
1846 // control messages must have bits 0x80|0x40|0x08
1847 // (type, length and sequence) set, and bits 0x02|0x01
1848 // (offset and priority) clear
1849 if ((*buf & 0xCB) != 0xC8)
1850 {
1851 LOG(1, s, t, "Bad control header %02X\n", *buf);
1852 STAT(tunnel_rx_errors);
1853 return;
1854 }
1855
1856 // check for duplicate tunnel open message
1857 if (!t && ns == 0)
1858 {
1859 int i;
1860
1861 //
1862 // Is this a duplicate of the first packet? (SCCRQ)
1863 //
1864 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1865 {
1866 if (tunnel[i].state != TUNNELOPENING ||
1867 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1868 tunnel[i].port != ntohs(addr->sin_port) )
1869 continue;
1870 t = i;
1871 LOG(3, s, t, "Duplicate SCCRQ?\n");
1872 break;
1873 }
1874 }
1875
1876 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1877 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1878
1879 // if no tunnel specified, assign one
1880 if (!t)
1881 {
1882 if (!(t = new_tunnel()))
1883 {
1884 LOG(1, 0, 0, "No more tunnels\n");
1885 STAT(tunnel_overflow);
1886 return;
1887 }
1888 tunnelclear(t);
1889 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1890 tunnel[t].port = ntohs(addr->sin_port);
1891 tunnel[t].window = 4; // default window
1892 STAT(tunnel_created);
1893 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1894 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1895 }
1896
1897 // If the 'ns' just received is not the 'nr' we're
1898 // expecting, just send an ack and drop it.
1899 //
1900 // if 'ns' is less, then we got a retransmitted packet.
1901 // if 'ns' is greater than missed a packet. Either way
1902 // we should ignore it.
1903 if (ns != tunnel[t].nr)
1904 {
1905 // is this the sequence we were expecting?
1906 STAT(tunnel_rx_errors);
1907 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1908 t, ns, tunnel[t].nr);
1909
1910 if (l) // Is this not a ZLB?
1911 controlnull(t);
1912 return;
1913 }
1914
1915 // This is used to time out old tunnels
1916 tunnel[t].lastrec = time_now;
1917
1918 // check sequence of this message
1919 {
1920 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1921 // some to clear maybe?
1922 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1923 {
1924 controlt *c = tunnel[t].controls;
1925 tunnel[t].controls = c->next;
1926 tunnel[t].controlc--;
1927 c->next = controlfree;
1928 controlfree = c;
1929 skip--;
1930 tunnel[t].try = 0; // we have progress
1931 }
1932
1933 // receiver advance (do here so quoted correctly in any sends below)
1934 if (l) tunnel[t].nr = (ns + 1);
1935 if (skip < 0) skip = 0;
1936 if (skip < tunnel[t].controlc)
1937 {
1938 // some control packets can now be sent that were previous stuck out of window
1939 int tosend = tunnel[t].window - skip;
1940 controlt *c = tunnel[t].controls;
1941 while (c && skip)
1942 {
1943 c = c->next;
1944 skip--;
1945 }
1946 while (c && tosend)
1947 {
1948 tunnel[t].try = 0; // first send
1949 tunnelsend(c->buf, c->length, t);
1950 c = c->next;
1951 tosend--;
1952 }
1953 }
1954 if (!tunnel[t].controlc)
1955 tunnel[t].retry = 0; // caught up
1956 }
1957 if (l)
1958 { // if not a null message
1959 int result = 0;
1960 int error = 0;
1961 char *msg = 0;
1962
1963 // process AVPs
1964 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1965 {
1966 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1967 uint8_t *b = p;
1968 uint8_t flags = *p;
1969 uint16_t mtype;
1970 if (n > l)
1971 {
1972 LOG(1, s, t, "Invalid length in AVP\n");
1973 STAT(tunnel_rx_errors);
1974 return;
1975 }
1976 p += n; // next
1977 l -= n;
1978 if (flags & 0x3C) // reserved bits, should be clear
1979 {
1980 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1981 fatal = flags;
1982 result = 2; // general error
1983 error = 3; // reserved field non-zero
1984 msg = 0;
1985 continue; // next
1986 }
1987 b += 2;
1988 if (*(uint16_t *) (b))
1989 {
1990 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1991 fatal = flags;
1992 result = 2; // general error
1993 error = 6; // generic vendor-specific error
1994 msg = "unsupported vendor-specific";
1995 continue; // next
1996 }
1997 b += 2;
1998 mtype = ntohs(*(uint16_t *) (b));
1999 b += 2;
2000 n -= 6;
2001
2002 if (flags & 0x40)
2003 {
2004 uint16_t orig_len;
2005
2006 // handle hidden AVPs
2007 if (!*config->l2tpsecret)
2008 {
2009 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2010 fatal = flags;
2011 result = 2; // general error
2012 error = 6; // generic vendor-specific error
2013 msg = "secret not specified";
2014 continue;
2015 }
2016 if (!session[s].random_vector_length)
2017 {
2018 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2019 fatal = flags;
2020 result = 2; // general error
2021 error = 6; // generic
2022 msg = "no random vector";
2023 continue;
2024 }
2025 if (n < 8)
2026 {
2027 LOG(2, s, t, "Short hidden AVP.\n");
2028 fatal = flags;
2029 result = 2; // general error
2030 error = 2; // length is wrong
2031 msg = 0;
2032 continue;
2033 }
2034
2035 // Unhide the AVP
2036 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2037
2038 orig_len = ntohs(*(uint16_t *) b);
2039 if (orig_len > n + 2)
2040 {
2041 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2042 orig_len, n);
2043
2044 fatal = flags;
2045 result = 2; // general error
2046 error = 2; // length is wrong
2047 msg = 0;
2048 continue;
2049 }
2050
2051 b += 2;
2052 n = orig_len;
2053 }
2054
2055 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2056 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2057
2058 switch (mtype)
2059 {
2060 case 0: // message type
2061 message = ntohs(*(uint16_t *) b);
2062 mandatory = flags & 0x80;
2063 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2064 break;
2065 case 1: // result code
2066 {
2067 uint16_t rescode = ntohs(*(uint16_t *) b);
2068 const char* resdesc = "(unknown)";
2069 if (message == 4)
2070 { /* StopCCN */
2071 resdesc = l2tp_stopccn_result_code(rescode);
2072 }
2073 else if (message == 14)
2074 { /* CDN */
2075 resdesc = l2tp_cdn_result_code(rescode);
2076 }
2077
2078 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2079 if (n >= 4)
2080 {
2081 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2082 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2083 }
2084 if (n > 4)
2085 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2086
2087 break;
2088 }
2089 break;
2090 case 2: // protocol version
2091 {
2092 version = ntohs(*(uint16_t *) (b));
2093 LOG(4, s, t, " Protocol version = %d\n", version);
2094 if (version && version != 0x0100)
2095 { // allow 0.0 and 1.0
2096 LOG(1, s, t, " Bad protocol version %04X\n", version);
2097 fatal = flags;
2098 result = 5; // unspported protocol version
2099 error = 0x0100; // supported version
2100 msg = 0;
2101 continue; // next
2102 }
2103 }
2104 break;
2105 case 3: // framing capabilities
2106 // LOG(4, s, t, "Framing capabilities\n");
2107 break;
2108 case 4: // bearer capabilities
2109 // LOG(4, s, t, "Bearer capabilities\n");
2110 break;
2111 case 5: // tie breaker
2112 // We never open tunnels, so we don't care about tie breakers
2113 // LOG(4, s, t, "Tie breaker\n");
2114 continue;
2115 case 6: // firmware revision
2116 // LOG(4, s, t, "Firmware revision\n");
2117 break;
2118 case 7: // host name
2119 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2120 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2121 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2122 // TBA - to send to RADIUS
2123 break;
2124 case 8: // vendor name
2125 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2126 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2127 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2128 break;
2129 case 9: // assigned tunnel
2130 tunnel[t].far = ntohs(*(uint16_t *) (b));
2131 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2132 break;
2133 case 10: // rx window
2134 tunnel[t].window = ntohs(*(uint16_t *) (b));
2135 if (!tunnel[t].window)
2136 tunnel[t].window = 1; // window of 0 is silly
2137 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2138 break;
2139 case 11: // Challenge
2140 {
2141 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2142 build_chap_response(b, 2, n, &chapresponse);
2143 }
2144 break;
2145 case 13: // Response
2146 // Why did they send a response? We never challenge.
2147 LOG(2, s, t, " received unexpected challenge response\n");
2148 break;
2149
2150 case 14: // assigned session
2151 asession = session[s].far = ntohs(*(uint16_t *) (b));
2152 LOG(4, s, t, " assigned session = %d\n", asession);
2153 break;
2154 case 15: // call serial number
2155 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2156 break;
2157 case 18: // bearer type
2158 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2159 // TBA - for RADIUS
2160 break;
2161 case 19: // framing type
2162 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2163 // TBA
2164 break;
2165 case 21: // called number
2166 memset(called, 0, sizeof(called));
2167 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2168 LOG(4, s, t, " Called <%s>\n", called);
2169 break;
2170 case 22: // calling number
2171 memset(calling, 0, sizeof(calling));
2172 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2173 LOG(4, s, t, " Calling <%s>\n", calling);
2174 break;
2175 case 23: // subtype
2176 break;
2177 case 24: // tx connect speed
2178 if (n == 4)
2179 {
2180 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2181 }
2182 else
2183 {
2184 // AS5300s send connect speed as a string
2185 char tmp[30];
2186 memset(tmp, 0, sizeof(tmp));
2187 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2188 session[s].tx_connect_speed = atol(tmp);
2189 }
2190 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2191 break;
2192 case 38: // rx connect speed
2193 if (n == 4)
2194 {
2195 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2196 }
2197 else
2198 {
2199 // AS5300s send connect speed as a string
2200 char tmp[30];
2201 memset(tmp, 0, sizeof(tmp));
2202 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2203 session[s].rx_connect_speed = atol(tmp);
2204 }
2205 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2206 break;
2207 case 25: // Physical Channel ID
2208 {
2209 uint32_t tmp = ntohl(*(uint32_t *) b);
2210 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2211 break;
2212 }
2213 case 29: // Proxy Authentication Type
2214 {
2215 uint16_t atype = ntohs(*(uint16_t *)b);
2216 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2217 if (atype == 2)
2218 authtype = AUTHCHAP;
2219 else if (atype == 3)
2220 authtype = AUTHPAP;
2221
2222 break;
2223 }
2224 case 30: // Proxy Authentication Name
2225 {
2226 char authname[64];
2227 memset(authname, 0, sizeof(authname));
2228 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2229 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2230 authname);
2231 break;
2232 }
2233 case 31: // Proxy Authentication Challenge
2234 {
2235 LOG(4, s, t, " Proxy Auth Challenge\n");
2236 if (sess_local[s].radius)
2237 memcpy(radius[sess_local[s].radius].auth, b, 16);
2238 break;
2239 }
2240 case 32: // Proxy Authentication ID
2241 {
2242 uint16_t authid = ntohs(*(uint16_t *)(b));
2243 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2244 if (sess_local[s].radius)
2245 radius[sess_local[s].radius].id = authid;
2246 break;
2247 }
2248 case 33: // Proxy Authentication Response
2249 LOG(4, s, t, " Proxy Auth Response\n");
2250 break;
2251 case 27: // last sent lcp
2252 { // find magic number
2253 uint8_t *p = b, *e = p + n;
2254 while (p + 1 < e && p[1] && p + p[1] <= e)
2255 {
2256 if (*p == 5 && p[1] == 6) // Magic-Number
2257 amagic = ntohl(*(uint32_t *) (p + 2));
2258 else if (*p == 3 && p[1] == 4 && *(uint16_t *) (p + 2) == htons(PPPPAP)) // Authentication-Protocol (PAP)
2259 authtype = AUTHPAP;
2260 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol (CHAP)
2261 authtype = AUTHCHAP;
2262 else if (*p == 7) // Protocol-Field-Compression
2263 aflags |= SESSIONPFC;
2264 else if (*p == 8) // Address-and-Control-Field-Compression
2265 aflags |= SESSIONACFC;
2266 p += p[1];
2267 }
2268 }
2269 break;
2270 case 28: // last recv lcp confreq
2271 break;
2272 case 26: // Initial Received LCP CONFREQ
2273 break;
2274 case 39: // seq required - we control it as an LNS anyway...
2275 break;
2276 case 36: // Random Vector
2277 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2278 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2279 if (n > sizeof(session[s].random_vector))
2280 n = sizeof(session[s].random_vector);
2281 memcpy(session[s].random_vector, b, n);
2282 session[s].random_vector_length = n;
2283 break;
2284 default:
2285 {
2286 static char e[] = "unknown AVP 0xXXXX";
2287 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2288 fatal = flags;
2289 result = 2; // general error
2290 error = 8; // unknown mandatory AVP
2291 sprintf((msg = e) + 14, "%04x", mtype);
2292 continue; // next
2293 }
2294 }
2295 }
2296 // process message
2297 if (fatal & 0x80)
2298 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2299 else
2300 switch (message)
2301 {
2302 case 1: // SCCRQ - Start Control Connection Request
2303 tunnel[t].state = TUNNELOPENING;
2304 if (main_quit != QUIT_SHUTDOWN)
2305 {
2306 controlt *c = controlnew(2); // sending SCCRP
2307 control16(c, 2, version, 1); // protocol version
2308 control32(c, 3, 3, 1); // framing
2309 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2310 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2311 control16(c, 9, t, 1); // assigned tunnel
2312 controladd(c, t, 0); // send the resply
2313 }
2314 else
2315 {
2316 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2317 }
2318 break;
2319 case 2: // SCCRP
2320 tunnel[t].state = TUNNELOPEN;
2321 break;
2322 case 3: // SCCN
2323 tunnel[t].state = TUNNELOPEN;
2324 controlnull(t); // ack
2325 break;
2326 case 4: // StopCCN
2327 controlnull(t); // ack
2328 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2329 break;
2330 case 6: // HELLO
2331 controlnull(t); // simply ACK
2332 break;
2333 case 7: // OCRQ
2334 // TBA
2335 break;
2336 case 8: // OCRO
2337 // TBA
2338 break;
2339 case 9: // OCCN
2340 // TBA
2341 break;
2342 case 10: // ICRQ
2343 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2344 {
2345 controlt *c = controlnew(11); // ICRP
2346
2347 s = sessionfree;
2348 sessionfree = session[s].next;
2349 memset(&session[s], 0, sizeof(session[s]));
2350
2351 if (s > config->cluster_highest_sessionid)
2352 config->cluster_highest_sessionid = s;
2353
2354 session[s].opened = time_now;
2355 session[s].tunnel = t;
2356 session[s].far = asession;
2357 session[s].last_packet = time_now;
2358 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2359 control16(c, 14, s, 1); // assigned session
2360 controladd(c, t, asession); // send the reply
2361
2362 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2363 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2364
2365 session[s].ppp.phase = Establish;
2366 session[s].ppp.lcp = Starting;
2367
2368 STAT(session_created);
2369 break;
2370 }
2371
2372 {
2373 controlt *c = controlnew(14); // CDN
2374 if (!sessionfree)
2375 {
2376 STAT(session_overflow);
2377 LOG(1, 0, t, "No free sessions\n");
2378 control16(c, 1, 4, 0); // temporary lack of resources
2379 }
2380 else
2381 control16(c, 1, 2, 7); // shutting down, try another
2382
2383 controladd(c, t, asession); // send the message
2384 }
2385 return;
2386 case 11: // ICRP
2387 // TBA
2388 break;
2389 case 12: // ICCN
2390 if (amagic == 0) amagic = time_now;
2391 session[s].magic = amagic; // set magic number
2392 session[s].l2tp_flags = aflags; // set flags received
2393 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
2394 controlnull(t); // ack
2395
2396 // proxy authentication type is not supported
2397 if (!(config->radius_authtypes & authtype))
2398 authtype = config->radius_authprefer;
2399
2400 // start LCP
2401 sendlcp(t, s, authtype);
2402 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2403 sess_local[s].lcp.conf_sent = 1;
2404 sess_local[s].lcp.nak_sent = 0;
2405 sess_local[s].lcp_authtype = authtype;
2406 session[s].ppp.lcp = RequestSent;
2407
2408 break;
2409 case 14: // CDN
2410 controlnull(t); // ack
2411 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2412 break;
2413 case 0xFFFF:
2414 LOG(1, s, t, "Missing message type\n");
2415 break;
2416 default:
2417 STAT(tunnel_rx_errors);
2418 if (mandatory)
2419 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2420 else
2421 LOG(1, s, t, "Unknown message type %d\n", message);
2422 break;
2423 }
2424 if (chapresponse) free(chapresponse);
2425 cluster_send_tunnel(t);
2426 }
2427 else
2428 {
2429 LOG(4, s, t, " Got a ZLB ack\n");
2430 }
2431 }
2432 else
2433 { // data
2434 uint16_t prot;
2435
2436 LOG_HEX(5, "Receive Tunnel Data", p, l);
2437 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2438 { // HDLC address header, discard
2439 p += 2;
2440 l -= 2;
2441 }
2442 if (l < 2)
2443 {
2444 LOG(1, s, t, "Short ppp length %d\n", l);
2445 STAT(tunnel_rx_errors);
2446 return;
2447 }
2448 if (*p & 1)
2449 {
2450 prot = *p++;
2451 l--;
2452 }
2453 else
2454 {
2455 prot = ntohs(*(uint16_t *) p);
2456 p += 2;
2457 l -= 2;
2458 }
2459
2460 if (s && !session[s].opened) // Is something wrong??
2461 {
2462 if (!config->cluster_iam_master)
2463 {
2464 // Pass it off to the master to deal with..
2465 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2466 return;
2467 }
2468
2469
2470 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2471 STAT(tunnel_rx_errors);
2472 return;
2473 }
2474
2475 if (prot == PPPPAP)
2476 {
2477 session[s].last_packet = time_now;
2478 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2479 processpap(t, s, p, l);
2480 }
2481 else if (prot == PPPCHAP)
2482 {
2483 session[s].last_packet = time_now;
2484 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2485 processchap(t, s, p, l);
2486 }
2487 else if (prot == PPPLCP)
2488 {
2489 session[s].last_packet = time_now;
2490 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2491 processlcp(t, s, p, l);
2492 }
2493 else if (prot == PPPIPCP)
2494 {
2495 session[s].last_packet = time_now;
2496 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2497 processipcp(t, s, p, l);
2498 }
2499 else if (prot == PPPIPV6CP)
2500 {
2501 session[s].last_packet = time_now;
2502 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2503 processipv6cp(t, s, p, l);
2504 }
2505 else if (prot == PPPCCP)
2506 {
2507 session[s].last_packet = time_now;
2508 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2509 processccp(t, s, p, l);
2510 }
2511 else if (prot == PPPIP)
2512 {
2513 if (session[s].die)
2514 {
2515 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2516 return; // closing session, PPP not processed
2517 }
2518
2519 session[s].last_packet = time_now;
2520 if (session[s].walled_garden && !config->cluster_iam_master)
2521 {
2522 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2523 return;
2524 }
2525
2526 processipin(t, s, p, l);
2527 }
2528 else if (prot == PPPIPV6)
2529 {
2530 if (!config->ipv6_prefix.s6_addr[0])
2531 {
2532 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2533 return;
2534 }
2535 if (session[s].die)
2536 {
2537 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2538 return; // closing session, PPP not processed
2539 }
2540
2541 session[s].last_packet = time_now;
2542 if (session[s].walled_garden && !config->cluster_iam_master)
2543 {
2544 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2545 return;
2546 }
2547
2548 processipv6in(t, s, p, l);
2549 }
2550 else
2551 {
2552 STAT(tunnel_rx_errors);
2553 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2554 }
2555 }
2556 }
2557
2558 // read and process packet on tun
2559 static void processtun(uint8_t * buf, int len)
2560 {
2561 LOG_HEX(5, "Receive TUN Data", buf, len);
2562 STAT(tun_rx_packets);
2563 INC_STAT(tun_rx_bytes, len);
2564
2565 CSTAT(processtun);
2566
2567 eth_rx_pkt++;
2568 eth_rx += len;
2569 if (len < 22)
2570 {
2571 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2572 STAT(tun_rx_errors);
2573 return;
2574 }
2575
2576 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2577 processipout(buf, len);
2578 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2579 && config->ipv6_prefix.s6_addr[0])
2580 processipv6out(buf, len);
2581
2582 // Else discard.
2583 }
2584
2585 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2586 // that we look at the whole of the tunnel, radius and session tables
2587 // every second
2588 static void regular_cleanups(double period)
2589 {
2590 // Next tunnel, radius and session to check for actions on.
2591 static tunnelidt t = 0;
2592 static int r = 0;
2593 static sessionidt s = 0;
2594
2595 int t_actions = 0;
2596 int r_actions = 0;
2597 int s_actions = 0;
2598
2599 int t_slice;
2600 int r_slice;
2601 int s_slice;
2602
2603 int i;
2604 int a;
2605
2606 // divide up tables into slices based on the last run
2607 t_slice = config->cluster_highest_tunnelid * period;
2608 r_slice = (MAXRADIUS - 1) * period;
2609 s_slice = config->cluster_highest_sessionid * period;
2610
2611 if (t_slice < 1)
2612 t_slice = 1;
2613 else if (t_slice > config->cluster_highest_tunnelid)
2614 t_slice = config->cluster_highest_tunnelid;
2615
2616 if (r_slice < 1)
2617 r_slice = 1;
2618 else if (r_slice > (MAXRADIUS - 1))
2619 r_slice = MAXRADIUS - 1;
2620
2621 if (s_slice < 1)
2622 s_slice = 1;
2623 else if (s_slice > config->cluster_highest_sessionid)
2624 s_slice = config->cluster_highest_sessionid;
2625
2626 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2627
2628 for (i = 0; i < t_slice; i++)
2629 {
2630 t++;
2631 if (t > config->cluster_highest_tunnelid)
2632 t = 1;
2633
2634 // check for expired tunnels
2635 if (tunnel[t].die && tunnel[t].die <= TIME)
2636 {
2637 STAT(tunnel_timeout);
2638 tunnelkill(t, "Expired");
2639 t_actions++;
2640 continue;
2641 }
2642 // check for message resend
2643 if (tunnel[t].retry && tunnel[t].controlc)
2644 {
2645 // resend pending messages as timeout on reply
2646 if (tunnel[t].retry <= TIME)
2647 {
2648 controlt *c = tunnel[t].controls;
2649 uint8_t w = tunnel[t].window;
2650 tunnel[t].try++; // another try
2651 if (tunnel[t].try > 5)
2652 tunnelkill(t, "Timeout on control message"); // game over
2653 else
2654 while (c && w--)
2655 {
2656 tunnelsend(c->buf, c->length, t);
2657 c = c->next;
2658 }
2659
2660 t_actions++;
2661 }
2662 }
2663 // Send hello
2664 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2665 {
2666 controlt *c = controlnew(6); // sending HELLO
2667 controladd(c, t, 0); // send the message
2668 LOG(3, 0, t, "Sending HELLO message\n");
2669 t_actions++;
2670 }
2671
2672 // Check for tunnel changes requested from the CLI
2673 if ((a = cli_tunnel_actions[t].action))
2674 {
2675 cli_tunnel_actions[t].action = 0;
2676 if (a & CLI_TUN_KILL)
2677 {
2678 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2679 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2680 t_actions++;
2681 }
2682 }
2683 }
2684
2685 for (i = 0; i < r_slice; i++)
2686 {
2687 r++;
2688 if (r >= MAXRADIUS)
2689 r = 1;
2690
2691 if (!radius[r].state)
2692 continue;
2693
2694 if (radius[r].retry <= TIME)
2695 {
2696 radiusretry(r);
2697 r_actions++;
2698 }
2699 }
2700
2701 for (i = 0; i < s_slice; i++)
2702 {
2703 s++;
2704 if (s > config->cluster_highest_sessionid)
2705 s = 1;
2706
2707 if (!session[s].opened) // Session isn't in use
2708 continue;
2709
2710 // check for expired sessions
2711 if (session[s].die)
2712 {
2713 if (session[s].die <= TIME)
2714 {
2715 sessionkill(s, "Expired");
2716 s_actions++;
2717 }
2718 continue;
2719 }
2720
2721 // PPP timeouts
2722 if (sess_local[s].lcp.restart >= time_now)
2723 {
2724 int next_state = session[s].ppp.lcp;
2725 switch (session[s].ppp.lcp)
2726 {
2727 case RequestSent:
2728 case AckReceived:
2729 next_state = RequestSent;
2730
2731 case AckSent:
2732 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2733 {
2734 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2735 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2736 sess_local[s].lcp.conf_sent++;
2737 sendlcp(t, s, sess_local[s].lcp_authtype);
2738 change_state(s, lcp, next_state);
2739 }
2740 else
2741 {
2742 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2743 STAT(session_timeout);
2744 }
2745
2746 s_actions++;
2747 }
2748
2749 if (session[s].die)
2750 continue;
2751 }
2752
2753 if (sess_local[s].ipcp.restart >= time_now)
2754 {
2755 int next_state = session[s].ppp.ipcp;
2756 switch (session[s].ppp.ipcp)
2757 {
2758 case RequestSent:
2759 case AckReceived:
2760 next_state = RequestSent;
2761
2762 case AckSent:
2763 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2764 {
2765 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2766 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2767 sess_local[s].ipcp.conf_sent++;
2768 sendipcp(t, s);
2769 change_state(s, ipcp, next_state);
2770 }
2771 else
2772 {
2773 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2774 STAT(session_timeout);
2775 }
2776
2777 s_actions++;
2778 }
2779
2780 if (session[s].die)
2781 continue;
2782 }
2783
2784 if (sess_local[s].ipv6cp.restart >= time_now)
2785 {
2786 int next_state = session[s].ppp.ipv6cp;
2787 switch (session[s].ppp.ipv6cp)
2788 {
2789 case RequestSent:
2790 case AckReceived:
2791 next_state = RequestSent;
2792
2793 case AckSent:
2794 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2795 {
2796 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2797 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2798 sess_local[s].ipv6cp.conf_sent++;
2799 sendipv6cp(t, s);
2800 change_state(s, ipv6cp, next_state);
2801 }
2802 else
2803 {
2804 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2805 change_state(s, ipv6cp, Stopped);
2806 }
2807
2808 s_actions++;
2809 }
2810 }
2811
2812 if (sess_local[s].ccp.restart >= time_now)
2813 {
2814 int next_state = session[s].ppp.ccp;
2815 switch (session[s].ppp.ccp)
2816 {
2817 case RequestSent:
2818 case AckReceived:
2819 next_state = RequestSent;
2820
2821 case AckSent:
2822 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2823 {
2824 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2825 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2826 sess_local[s].ccp.conf_sent++;
2827 sendccp(t, s);
2828 change_state(s, ccp, next_state);
2829 }
2830 else
2831 {
2832 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2833 change_state(s, ccp, Stopped);
2834 }
2835
2836 s_actions++;
2837 }
2838 }
2839
2840 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2841 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2842 {
2843 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2844 STAT(session_timeout);
2845 s_actions++;
2846 continue;
2847 }
2848
2849 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2850 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2851 {
2852 uint8_t b[MAXCONTROL] = {0};
2853
2854 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2855 if (!q) continue;
2856
2857 *q = EchoReq;
2858 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2859 *(uint16_t *)(q + 2) = htons(8); // Length
2860 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2861
2862 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2863 (int)(time_now - session[s].last_packet));
2864 tunnelsend(b, 24, session[s].tunnel); // send it
2865 s_actions++;
2866 }
2867
2868 // Check for actions requested from the CLI
2869 if ((a = cli_session_actions[s].action))
2870 {
2871 int send = 0;
2872
2873 cli_session_actions[s].action = 0;
2874 if (a & CLI_SESS_KILL)
2875 {
2876 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2877 sessionshutdown(s, "Requested by administrator.", 3, 0);
2878 a = 0; // dead, no need to check for other actions
2879 s_actions++;
2880 }
2881
2882 if (a & CLI_SESS_NOSNOOP)
2883 {
2884 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2885 session[s].snoop_ip = 0;
2886 session[s].snoop_port = 0;
2887 s_actions++;
2888 send++;
2889 }
2890 else if (a & CLI_SESS_SNOOP)
2891 {
2892 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2893 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2894 cli_session_actions[s].snoop_port);
2895
2896 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2897 session[s].snoop_port = cli_session_actions[s].snoop_port;
2898 s_actions++;
2899 send++;
2900 }
2901
2902 if (a & CLI_SESS_NOTHROTTLE)
2903 {
2904 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2905 throttle_session(s, 0, 0);
2906 s_actions++;
2907 send++;
2908 }
2909 else if (a & CLI_SESS_THROTTLE)
2910 {
2911 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2912 cli_session_actions[s].throttle_in,
2913 cli_session_actions[s].throttle_out);
2914
2915 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2916 s_actions++;
2917 send++;
2918 }
2919
2920 if (a & CLI_SESS_NOFILTER)
2921 {
2922 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2923 filter_session(s, 0, 0);
2924 s_actions++;
2925 send++;
2926 }
2927 else if (a & CLI_SESS_FILTER)
2928 {
2929 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2930 cli_session_actions[s].filter_in,
2931 cli_session_actions[s].filter_out);
2932
2933 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2934 s_actions++;
2935 send++;
2936 }
2937
2938 if (send)
2939 cluster_send_session(s);
2940 }
2941
2942 // RADIUS interim accounting
2943 if (config->radius_accounting && config->radius_interim > 0
2944 && session[s].ip && !session[s].walled_garden
2945 && !sess_local[s].radius // RADIUS already in progress
2946 && time_now - sess_local[s].last_interim >= config->radius_interim)
2947 {
2948 int rad = radiusnew(s);
2949 if (!rad)
2950 {
2951 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2952 STAT(radius_overflow);
2953 continue;
2954 }
2955
2956 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2957 session[s].user, session[s].unique_id);
2958
2959 radiussend(rad, RADIUSINTERIM);
2960 sess_local[s].last_interim = time_now;
2961 s_actions++;
2962 }
2963 }
2964
2965 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2966 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2967 }
2968
2969 //
2970 // Are we in the middle of a tunnel update, or radius
2971 // requests??
2972 //
2973 static int still_busy(void)
2974 {
2975 int i;
2976 static clockt last_talked = 0;
2977 static clockt start_busy_wait = 0;
2978
2979 if (!config->cluster_iam_master)
2980 {
2981 #ifdef BGP
2982 static time_t stopped_bgp = 0;
2983 if (bgp_configured)
2984 {
2985 if (!stopped_bgp)
2986 {
2987 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2988
2989 for (i = 0; i < BGP_NUM_PEERS; i++)
2990 if (bgp_peers[i].state == Established)
2991 bgp_stop(&bgp_peers[i]);
2992
2993 stopped_bgp = time_now;
2994
2995 // we don't want to become master
2996 cluster_send_ping(0);
2997
2998 return 1;
2999 }
3000
3001 if (time_now < (stopped_bgp + QUIT_DELAY))
3002 return 1;
3003 }
3004 #endif /* BGP */
3005
3006 return 0;
3007 }
3008
3009 if (main_quit == QUIT_SHUTDOWN)
3010 {
3011 static int dropped = 0;
3012 if (!dropped)
3013 {
3014 int i;
3015
3016 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3017 for (i = 1; i < MAXTUNNEL; i++)
3018 if (tunnel[i].ip || tunnel[i].state)
3019 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3020
3021 dropped = 1;
3022 }
3023 }
3024
3025 if (start_busy_wait == 0)
3026 start_busy_wait = TIME;
3027
3028 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3029 {
3030 if (!tunnel[i].controlc)
3031 continue;
3032
3033 if (last_talked != TIME)
3034 {
3035 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3036 last_talked = TIME;
3037 }
3038 return 1;
3039 }
3040
3041 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3042 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3043 {
3044 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3045 return 0;
3046 }
3047
3048 for (i = 1; i < MAXRADIUS; i++)
3049 {
3050 if (radius[i].state == RADIUSNULL)
3051 continue;
3052 if (radius[i].state == RADIUSWAIT)
3053 continue;
3054
3055 if (last_talked != TIME)
3056 {
3057 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3058 last_talked = TIME;
3059 }
3060 return 1;
3061 }
3062
3063 return 0;
3064 }
3065
3066 #ifdef HAVE_EPOLL
3067 # include <sys/epoll.h>
3068 #else
3069 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3070 # include "fake_epoll.h"
3071 #endif
3072
3073 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3074 #define BASE_FDS 6
3075
3076 // additional polled fds
3077 #ifdef BGP
3078 # define EXTRA_FDS BGP_NUM_PEERS
3079 #else
3080 # define EXTRA_FDS 0
3081 #endif
3082
3083 // main loop - gets packets on tun or udp and processes them
3084 static void mainloop(void)
3085 {
3086 int i;
3087 uint8_t buf[65536];
3088 clockt next_cluster_ping = 0; // send initial ping immediately
3089 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3090 int maxevent = sizeof(events)/sizeof(*events);
3091
3092 if ((epollfd = epoll_create(maxevent)) < 0)
3093 {
3094 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3095 exit(1);
3096 }
3097
3098 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3099 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3100
3101 /* setup our fds to poll for input */
3102 {
3103 static struct event_data d[BASE_FDS];
3104 struct epoll_event e;
3105
3106 e.events = EPOLLIN;
3107 i = 0;
3108
3109 d[i].type = FD_TYPE_CLI;
3110 e.data.ptr = &d[i++];
3111 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3112
3113 d[i].type = FD_TYPE_CLUSTER;
3114 e.data.ptr = &d[i++];
3115 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3116
3117 d[i].type = FD_TYPE_TUN;
3118 e.data.ptr = &d[i++];
3119 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3120
3121 d[i].type = FD_TYPE_UDP;
3122 e.data.ptr = &d[i++];
3123 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3124
3125 d[i].type = FD_TYPE_CONTROL;
3126 e.data.ptr = &d[i++];
3127 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3128
3129 d[i].type = FD_TYPE_DAE;
3130 e.data.ptr = &d[i++];
3131 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3132 }
3133
3134 #ifdef BGP
3135 signal(SIGPIPE, SIG_IGN);
3136 bgp_setup(config->as_number);
3137 if (config->bind_address)
3138 bgp_add_route(config->bind_address, 0xffffffff);
3139
3140 for (i = 0; i < BGP_NUM_PEERS; i++)
3141 {
3142 if (config->neighbour[i].name[0])
3143 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3144 config->neighbour[i].as, config->neighbour[i].keepalive,
3145 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3146 }
3147 #endif /* BGP */
3148
3149 while (!main_quit || still_busy())
3150 {
3151 int more = 0;
3152 int n;
3153
3154 if (config->reload_config)
3155 {
3156 // Update the config state based on config settings
3157 update_config();
3158 }
3159
3160 #ifdef BGP
3161 bgp_set_poll();
3162 #endif /* BGP */
3163
3164 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3165 STAT(select_called);
3166
3167 TIME = now(NULL);
3168 if (n < 0)
3169 {
3170 if (errno == EINTR ||
3171 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3172 continue;
3173
3174 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3175 break; // exit
3176 }
3177
3178 if (n)
3179 {
3180 struct sockaddr_in addr;
3181 socklen_t alen;
3182 int c, s;
3183 int udp_ready = 0;
3184 int tun_ready = 0;
3185 int cluster_ready = 0;
3186 int udp_pkts = 0;
3187 int tun_pkts = 0;
3188 int cluster_pkts = 0;
3189 #ifdef BGP
3190 uint32_t bgp_events[BGP_NUM_PEERS];
3191 memset(bgp_events, 0, sizeof(bgp_events));
3192 #endif /* BGP */
3193
3194 for (c = n, i = 0; i < c; i++)
3195 {
3196 struct event_data *d = events[i].data.ptr;
3197 switch (d->type)
3198 {
3199 case FD_TYPE_CLI: // CLI connections
3200 {
3201 int cli;
3202
3203 alen = sizeof(addr);
3204 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3205 {
3206 cli_do(cli);
3207 close(cli);
3208 }
3209 else
3210 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3211
3212 n--;
3213 break;
3214 }
3215
3216 // these are handled below, with multiple interleaved reads
3217 case FD_TYPE_CLUSTER: cluster_ready++; break;
3218 case FD_TYPE_TUN: tun_ready++; break;
3219 case FD_TYPE_UDP: udp_ready++; break;
3220
3221 case FD_TYPE_CONTROL: // nsctl commands
3222 alen = sizeof(addr);
3223 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3224 n--;
3225 break;
3226
3227 case FD_TYPE_DAE: // DAE requests
3228 alen = sizeof(addr);
3229 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3230 n--;
3231 break;
3232
3233 case FD_TYPE_RADIUS: // RADIUS response
3234 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3235 if (s >= 0 && config->cluster_iam_master)
3236 processrad(buf, s, d->index);
3237
3238 n--;
3239 break;
3240
3241 #ifdef BGP
3242 case FD_TYPE_BGP:
3243 bgp_events[d->index] = events[i].events;
3244 n--;
3245 break;
3246 #endif /* BGP */
3247
3248 default:
3249 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3250 }
3251 }
3252
3253 #ifdef BGP
3254 bgp_process(bgp_events);
3255 #endif /* BGP */
3256
3257 for (c = 0; n && c < config->multi_read_count; c++)
3258 {
3259 // L2TP
3260 if (udp_ready)
3261 {
3262 alen = sizeof(addr);
3263 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3264 {
3265 processudp(buf, s, &addr);
3266 udp_pkts++;
3267 }
3268 else
3269 {
3270 udp_ready = 0;
3271 n--;
3272 }
3273 }
3274
3275 // incoming IP
3276 if (tun_ready)
3277 {
3278 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3279 {
3280 processtun(buf, s);
3281 tun_pkts++;
3282 }
3283 else
3284 {
3285 tun_ready = 0;
3286 n--;
3287 }
3288 }
3289
3290 // cluster
3291 if (cluster_ready)
3292 {
3293 alen = sizeof(addr);
3294 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3295 {
3296 processcluster(buf, s, addr.sin_addr.s_addr);
3297 cluster_pkts++;
3298 }
3299 else
3300 {
3301 cluster_ready = 0;
3302 n--;
3303 }
3304 }
3305 }
3306
3307 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3308 STAT(multi_read_used);
3309
3310 if (c >= config->multi_read_count)
3311 {
3312 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3313 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3314
3315 STAT(multi_read_exceeded);
3316 more++;
3317 }
3318 }
3319
3320 // Runs on every machine (master and slaves).
3321 if (next_cluster_ping <= TIME)
3322 {
3323 // Check to see which of the cluster is still alive..
3324
3325 cluster_send_ping(basetime); // Only does anything if we're a slave
3326 cluster_check_master(); // ditto.
3327
3328 cluster_heartbeat(); // Only does anything if we're a master.
3329 cluster_check_slaves(); // ditto.
3330
3331 master_update_counts(); // If we're a slave, send our byte counters to our master.
3332
3333 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3334 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3335 else
3336 next_cluster_ping = TIME + config->cluster_hb_interval;
3337 }
3338
3339 if (!config->cluster_iam_master)
3340 continue;
3341
3342 // Run token bucket filtering queue..
3343 // Only run it every 1/10th of a second.
3344 {
3345 static clockt last_run = 0;
3346 if (last_run != TIME)
3347 {
3348 last_run = TIME;
3349 tbf_run_timer();
3350 }
3351 }
3352
3353 // Handle timeouts, retries etc.
3354 {
3355 static double last_clean = 0;
3356 double this_clean;
3357 double diff;
3358
3359 TIME = now(&this_clean);
3360 diff = this_clean - last_clean;
3361
3362 // Run during idle time (after we've handled
3363 // all incoming packets) or every 1/10th sec
3364 if (!more || diff > 0.1)
3365 {
3366 regular_cleanups(diff);
3367 last_clean = this_clean;
3368 }
3369 }
3370
3371 if (*config->accounting_dir)
3372 {
3373 static clockt next_acct = 0;
3374 static clockt next_shut_acct = 0;
3375
3376 if (next_acct <= TIME)
3377 {
3378 // Dump accounting data
3379 next_acct = TIME + ACCT_TIME;
3380 next_shut_acct = TIME + ACCT_SHUT_TIME;
3381 dump_acct_info(1);
3382 }
3383 else if (next_shut_acct <= TIME)
3384 {
3385 // Dump accounting data for shutdown sessions
3386 next_shut_acct = TIME + ACCT_SHUT_TIME;
3387 if (shut_acct_n)
3388 dump_acct_info(0);
3389 }
3390 }
3391 }
3392
3393 // Are we the master and shutting down??
3394 if (config->cluster_iam_master)
3395 cluster_heartbeat(); // Flush any queued changes..
3396
3397 // Ok. Notify everyone we're shutting down. If we're
3398 // the master, this will force an election.
3399 cluster_send_ping(0);
3400
3401 //
3402 // Important!!! We MUST not process any packets past this point!
3403 LOG(1, 0, 0, "Shutdown complete\n");
3404 }
3405
3406 static void stripdomain(char *host)
3407 {
3408 char *p;
3409
3410 if ((p = strchr(host, '.')))
3411 {
3412 char *domain = 0;
3413 char _domain[1024];
3414
3415 // strip off domain
3416 FILE *resolv = fopen("/etc/resolv.conf", "r");
3417 if (resolv)
3418 {
3419 char buf[1024];
3420 char *b;
3421
3422 while (fgets(buf, sizeof(buf), resolv))
3423 {
3424 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3425 continue;
3426
3427 if (!isspace(buf[6]))
3428 continue;
3429
3430 b = buf + 7;
3431 while (isspace(*b)) b++;
3432
3433 if (*b)
3434 {
3435 char *d = b;
3436 while (*b && !isspace(*b)) b++;
3437 *b = 0;
3438 if (buf[0] == 'd') // domain is canonical
3439 {
3440 domain = d;
3441 break;
3442 }
3443
3444 // first search line
3445 if (!domain)
3446 {
3447 // hold, may be subsequent domain line
3448 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3449 domain = _domain;
3450 }
3451 }
3452 }
3453
3454 fclose(resolv);
3455 }
3456
3457 if (domain)
3458 {
3459 int hl = strlen(host);
3460 int dl = strlen(domain);
3461 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3462 host[hl -dl - 1] = 0;
3463 }
3464 else
3465 {
3466 *p = 0; // everything after first dot
3467 }
3468 }
3469 }
3470
3471 // Init data structures
3472 static void initdata(int optdebug, char *optconfig)
3473 {
3474 int i;
3475
3476 if (!(config = shared_malloc(sizeof(configt))))
3477 {
3478 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3479 exit(1);
3480 }
3481
3482 memset(config, 0, sizeof(configt));
3483 time(&config->start_time);
3484 strncpy(config->config_file, optconfig, strlen(optconfig));
3485 config->debug = optdebug;
3486 config->num_tbfs = MAXTBFS;
3487 config->rl_rate = 28; // 28kbps
3488 config->cluster_master_min_adv = 1;
3489 config->ppp_restart_time = 3;
3490 config->ppp_max_configure = 10;
3491 config->ppp_max_failure = 5;
3492 strcpy(config->random_device, RANDOMDEVICE);
3493
3494 log_stream = stderr;
3495
3496 #ifdef RINGBUFFER
3497 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3498 {
3499 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3500 exit(1);
3501 }
3502 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3503 #endif
3504
3505 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3506 {
3507 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3508 exit(1);
3509 }
3510 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3511 {
3512 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3513 exit(1);
3514 }
3515 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3516 {
3517 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3518 exit(1);
3519 }
3520
3521 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3522 {
3523 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3524 exit(1);
3525 }
3526
3527 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3528 {
3529 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3530 exit(1);
3531 }
3532
3533 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3534 {
3535 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3536 exit(1);
3537 }
3538
3539 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3540 {
3541 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3542 exit(1);
3543 }
3544 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3545
3546 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3547 {
3548 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3549 exit(1);
3550 }
3551 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3552
3553 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3554 {
3555 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3556 exit(1);
3557 }
3558 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3559
3560 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3561 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3562 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3563 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3564
3565 // Put all the sessions on the free list marked as undefined.
3566 for (i = 1; i < MAXSESSION; i++)
3567 {
3568 session[i].next = i + 1;
3569 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3570 }
3571 session[MAXSESSION - 1].next = 0;
3572 sessionfree = 1;
3573
3574 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3575 for (i = 1; i < MAXTUNNEL; i++)
3576 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3577
3578 if (!*hostname)
3579 {
3580 // Grab my hostname unless it's been specified
3581 gethostname(hostname, sizeof(hostname));
3582 stripdomain(hostname);
3583 }
3584
3585 _statistics->start_time = _statistics->last_reset = time(NULL);
3586
3587 #ifdef BGP
3588 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3589 {
3590 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3591 exit(1);
3592 }
3593 #endif /* BGP */
3594 }
3595
3596 static int assign_ip_address(sessionidt s)
3597 {
3598 uint32_t i;
3599 int best = -1;
3600 time_t best_time = time_now;
3601 char *u = session[s].user;
3602 char reuse = 0;
3603
3604
3605 CSTAT(assign_ip_address);
3606
3607 for (i = 1; i < ip_pool_size; i++)
3608 {
3609 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3610 continue;
3611
3612 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3613 {
3614 best = i;
3615 reuse = 1;
3616 break;
3617 }
3618
3619 if (ip_address_pool[i].last < best_time)
3620 {
3621 best = i;
3622 if (!(best_time = ip_address_pool[i].last))
3623 break; // never used, grab this one
3624 }
3625 }
3626
3627 if (best < 0)
3628 {
3629 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3630 return 0;
3631 }
3632
3633 session[s].ip = ip_address_pool[best].address;
3634 session[s].ip_pool_index = best;
3635 ip_address_pool[best].assigned = 1;
3636 ip_address_pool[best].last = time_now;
3637 ip_address_pool[best].session = s;
3638 if (session[s].walled_garden)
3639 /* Don't track addresses of users in walled garden (note: this
3640 means that their address isn't "sticky" even if they get
3641 un-gardened). */
3642 ip_address_pool[best].user[0] = 0;
3643 else
3644 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3645
3646 STAT(ip_allocated);
3647 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3648 reuse ? "Reusing" : "Allocating", best);
3649
3650 return 1;
3651 }
3652
3653 static void free_ip_address(sessionidt s)
3654 {
3655 int i = session[s].ip_pool_index;
3656
3657
3658 CSTAT(free_ip_address);
3659
3660 if (!session[s].ip)
3661 return; // what the?
3662
3663 if (i < 0) // Is this actually part of the ip pool?
3664 i = 0;
3665
3666 STAT(ip_freed);
3667 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3668 session[s].ip = 0;
3669 ip_address_pool[i].assigned = 0;
3670 ip_address_pool[i].session = 0;
3671 ip_address_pool[i].last = time_now;
3672 }
3673
3674 //
3675 // Fsck the address pool against the session table.
3676 // Normally only called when we become a master.
3677 //
3678 // This isn't perfect: We aren't keep tracking of which
3679 // users used to have an IP address.
3680 //
3681 void rebuild_address_pool(void)
3682 {
3683 int i;
3684
3685 //
3686 // Zero the IP pool allocation, and build
3687 // a map from IP address to pool index.
3688 for (i = 1; i < MAXIPPOOL; ++i)
3689 {
3690 ip_address_pool[i].assigned = 0;
3691 ip_address_pool[i].session = 0;
3692 if (!ip_address_pool[i].address)
3693 continue;
3694
3695 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3696 }
3697
3698 for (i = 0; i < MAXSESSION; ++i)
3699 {
3700 int ipid;
3701 if (!(session[i].opened && session[i].ip))
3702 continue;
3703
3704 ipid = - lookup_ipmap(htonl(session[i].ip));
3705
3706 if (session[i].ip_pool_index < 0)
3707 {
3708 // Not allocated out of the pool.
3709 if (ipid < 1) // Not found in the pool either? good.
3710 continue;
3711
3712 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3713 i, fmtaddr(session[i].ip, 0), ipid);
3714
3715 // Fall through and process it as part of the pool.
3716 }
3717
3718
3719 if (ipid > MAXIPPOOL || ipid < 0)
3720 {
3721 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3722 ipid = -1;
3723 session[i].ip_pool_index = ipid;
3724 continue;
3725 }
3726
3727 ip_address_pool[ipid].assigned = 1;
3728 ip_address_pool[ipid].session = i;
3729 ip_address_pool[ipid].last = time_now;
3730 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3731 session[i].ip_pool_index = ipid;
3732 cache_ipmap(session[i].ip, i); // Fix the ip map.
3733 }
3734 }
3735
3736 //
3737 // Fix the address pool to match a changed session.
3738 // (usually when the master sends us an update).
3739 static void fix_address_pool(int sid)
3740 {
3741 int ipid;
3742
3743 ipid = session[sid].ip_pool_index;
3744
3745 if (ipid > ip_pool_size)
3746 return; // Ignore it. rebuild_address_pool will fix it up.
3747
3748 if (ip_address_pool[ipid].address != session[sid].ip)
3749 return; // Just ignore it. rebuild_address_pool will take care of it.
3750
3751 ip_address_pool[ipid].assigned = 1;
3752 ip_address_pool[ipid].session = sid;
3753 ip_address_pool[ipid].last = time_now;
3754 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3755 }
3756
3757 //
3758 // Add a block of addresses to the IP pool to hand out.
3759 //
3760 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3761 {
3762 int i;
3763 if (mask == 0)
3764 mask = 0xffffffff; // Host route only.
3765
3766 addr &= mask;
3767
3768 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3769 return ;
3770
3771 for (i = addr ;(i & mask) == addr; ++i)
3772 {
3773 if ((i & 0xff) == 0 || (i&0xff) == 255)
3774 continue; // Skip 0 and broadcast addresses.
3775
3776 ip_address_pool[ip_pool_size].address = i;
3777 ip_address_pool[ip_pool_size].assigned = 0;
3778 ++ip_pool_size;
3779 if (ip_pool_size >= MAXIPPOOL)
3780 {
3781 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3782 return;
3783 }
3784 }
3785 }
3786
3787 // Initialize the IP address pool
3788 static void initippool()
3789 {
3790 FILE *f;
3791 char *p;
3792 char buf[4096];
3793 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3794
3795 if (!(f = fopen(IPPOOLFILE, "r")))
3796 {
3797 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3798 exit(1);
3799 }
3800
3801 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3802 {
3803 char *pool = buf;
3804 buf[4095] = 0; // Force it to be zero terminated/
3805
3806 if (*buf == '#' || *buf == '\n')
3807 continue; // Skip comments / blank lines
3808 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3809 if ((p = (char *)strchr(buf, ':')))
3810 {
3811 in_addr_t src;
3812 *p = '\0';
3813 src = inet_addr(buf);
3814 if (src == INADDR_NONE)
3815 {
3816 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3817 exit(1);
3818 }
3819 // This entry is for a specific IP only
3820 if (src != config->bind_address)
3821 continue;
3822 *p = ':';
3823 pool = p+1;
3824 }
3825 if ((p = (char *)strchr(pool, '/')))
3826 {
3827 // It's a range
3828 int numbits = 0;
3829 in_addr_t start = 0, mask = 0;
3830
3831 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3832 *p++ = 0;
3833 if (!*p || !(numbits = atoi(p)))
3834 {
3835 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3836 continue;
3837 }
3838 start = ntohl(inet_addr(pool));
3839 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3840
3841 // Add a static route for this pool
3842 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3843 fmtaddr(htonl(start), 0), 32 + mask);
3844
3845 routeset(0, start, mask, 0, 1);
3846
3847 add_to_ip_pool(start, mask);
3848 }
3849 else
3850 {
3851 // It's a single ip address
3852 add_to_ip_pool(inet_addr(pool), 0);
3853 }
3854 }
3855 fclose(f);
3856 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3857 }
3858
3859 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3860 {
3861 struct sockaddr_in snoop_addr = {0};
3862 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3863 return;
3864
3865 snoop_addr.sin_family = AF_INET;
3866 snoop_addr.sin_addr.s_addr = destination;
3867 snoop_addr.sin_port = ntohs(port);
3868
3869 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3870 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3871 htons(snoop_addr.sin_port));
3872
3873 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3874 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3875
3876 STAT(packets_snooped);
3877 }
3878
3879 static int dump_session(FILE **f, sessiont *s)
3880 {
3881 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3882 return 1;
3883
3884 if (!*f)
3885 {
3886 char filename[1024];
3887 char timestr[64];
3888 time_t now = time(NULL);
3889
3890 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3891 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3892
3893 if (!(*f = fopen(filename, "w")))
3894 {
3895 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3896 return 0;
3897 }
3898
3899 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3900 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3901 "# host: %s\n"
3902 "# endpoint: %s\n"
3903 "# time: %ld\n"
3904 "# uptime: %ld\n"
3905 "# format: username ip qos uptxoctets downrxoctets\n",
3906 hostname,
3907 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3908 now,
3909 now - basetime);
3910 }
3911
3912 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3913 fprintf(*f, "%s %s %d %u %u\n",
3914 s->user, // username
3915 fmtaddr(htonl(s->ip), 0), // ip
3916 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3917 (uint32_t) s->cin_delta, // uptxoctets
3918 (uint32_t) s->cout_delta); // downrxoctets
3919
3920 s->cin_delta = s->cout_delta = 0;
3921
3922 return 1;
3923 }
3924
3925 static void dump_acct_info(int all)
3926 {
3927 int i;
3928 FILE *f = NULL;
3929
3930
3931 CSTAT(dump_acct_info);
3932
3933 if (shut_acct_n)
3934 {
3935 for (i = 0; i < shut_acct_n; i++)
3936 dump_session(&f, &shut_acct[i]);
3937
3938 shut_acct_n = 0;
3939 }
3940
3941 if (all)
3942 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3943 dump_session(&f, &session[i]);
3944
3945 if (f)
3946 fclose(f);
3947 }
3948
3949 // Main program
3950 int main(int argc, char *argv[])
3951 {
3952 int i;
3953 int optdebug = 0;
3954 char *optconfig = CONFIGFILE;
3955
3956 time(&basetime); // start clock
3957
3958 // scan args
3959 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3960 {
3961 switch (i)
3962 {
3963 case 'd':
3964 if (fork()) exit(0);
3965 setsid();
3966 freopen("/dev/null", "r", stdin);
3967 freopen("/dev/null", "w", stdout);
3968 freopen("/dev/null", "w", stderr);
3969 break;
3970 case 'v':
3971 optdebug++;
3972 break;
3973 case 'c':
3974 optconfig = optarg;
3975 break;
3976 case 'h':
3977 snprintf(hostname, sizeof(hostname), "%s", optarg);
3978 break;
3979 default:
3980 printf("Args are:\n"
3981 "\t-d\t\tDetach from terminal\n"
3982 "\t-c <file>\tConfig file\n"
3983 "\t-h <hostname>\tForce hostname\n"
3984 "\t-v\t\tDebug\n");
3985
3986 return (0);
3987 break;
3988 }
3989 }
3990
3991 // Start the timer routine off
3992 time(&time_now);
3993 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3994 signal(SIGALRM, sigalrm_handler);
3995 siginterrupt(SIGALRM, 0);
3996
3997 initplugins();
3998 initdata(optdebug, optconfig);
3999
4000 init_cli(hostname);
4001 read_config_file();
4002 init_tbf(config->num_tbfs);
4003
4004 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4005 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4006 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4007 {
4008 struct rlimit rlim;
4009 rlim.rlim_cur = RLIM_INFINITY;
4010 rlim.rlim_max = RLIM_INFINITY;
4011 // Remove the maximum core size
4012 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4013 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4014
4015 // Make core dumps go to /tmp
4016 chdir("/tmp");
4017 }
4018
4019 if (config->scheduler_fifo)
4020 {
4021 int ret;
4022 struct sched_param params = {0};
4023 params.sched_priority = 1;
4024
4025 if (get_nprocs() < 2)
4026 {
4027 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4028 config->scheduler_fifo = 0;
4029 }
4030 else
4031 {
4032 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4033 {
4034 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4035 }
4036 else
4037 {
4038 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4039 config->scheduler_fifo = 0;
4040 }
4041 }
4042 }
4043
4044 /* Set up the cluster communications port. */
4045 if (cluster_init() < 0)
4046 exit(1);
4047
4048 inittun();
4049 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4050
4051 initudp();
4052 initrad();
4053 initippool();
4054
4055 // seed prng
4056 {
4057 unsigned seed = time_now ^ getpid();
4058 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4059 srand(seed);
4060 }
4061
4062 signal(SIGHUP, sighup_handler);
4063 signal(SIGCHLD, sigchild_handler);
4064 signal(SIGTERM, shutdown_handler);
4065 signal(SIGINT, shutdown_handler);
4066 signal(SIGQUIT, shutdown_handler);
4067
4068 // Prevent us from getting paged out
4069 if (config->lock_pages)
4070 {
4071 if (!mlockall(MCL_CURRENT))
4072 LOG(1, 0, 0, "Locking pages into memory\n");
4073 else
4074 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4075 }
4076
4077 alarm(1);
4078
4079 // Drop privileges here
4080 if (config->target_uid > 0 && geteuid() == 0)
4081 setuid(config->target_uid);
4082
4083 mainloop();
4084
4085 /* remove plugins (so cleanup code gets run) */
4086 plugins_done();
4087
4088 // Remove the PID file if we wrote it
4089 if (config->wrote_pid && *config->pid_file == '/')
4090 unlink(config->pid_file);
4091
4092 /* kill CLI children */
4093 signal(SIGTERM, SIG_IGN);
4094 kill(0, SIGTERM);
4095 return 0;
4096 }
4097
4098 static void sighup_handler(int sig)
4099 {
4100 if (log_stream)
4101 {
4102 if (log_stream != stderr)
4103 fclose(log_stream);
4104
4105 log_stream = NULL;
4106 }
4107
4108 read_config_file();
4109 }
4110
4111 static void sigalrm_handler(int sig)
4112 {
4113 // Log current traffic stats
4114
4115 snprintf(config->bandwidth, sizeof(config->bandwidth),
4116 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4117 (udp_rx / 1024.0 / 1024.0 * 8),
4118 (eth_tx / 1024.0 / 1024.0 * 8),
4119 (eth_rx / 1024.0 / 1024.0 * 8),
4120 (udp_tx / 1024.0 / 1024.0 * 8),
4121 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4122 udp_rx_pkt, eth_rx_pkt);
4123
4124 udp_tx = udp_rx = 0;
4125 udp_rx_pkt = eth_rx_pkt = 0;
4126 eth_tx = eth_rx = 0;
4127
4128 if (config->dump_speed)
4129 printf("%s\n", config->bandwidth);
4130
4131 // Update the internal time counter
4132 time(&time_now);
4133 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4134 alarm(1);
4135
4136 {
4137 // Run timer hooks
4138 struct param_timer p = { time_now };
4139 run_plugins(PLUGIN_TIMER, &p);
4140 }
4141
4142 }
4143
4144 static void shutdown_handler(int sig)
4145 {
4146 LOG(1, 0, 0, "Shutting down\n");
4147 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4148 }
4149
4150 static void sigchild_handler(int sig)
4151 {
4152 while (waitpid(-1, NULL, WNOHANG) > 0)
4153 ;
4154 }
4155
4156 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4157 {
4158 MD5_CTX ctx;
4159 *challenge_response = NULL;
4160
4161 if (!*config->l2tpsecret)
4162 {
4163 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4164 return;
4165 }
4166
4167 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4168
4169 *challenge_response = calloc(17, 1);
4170
4171 MD5_Init(&ctx);
4172 MD5_Update(&ctx, &id, 1);
4173 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4174 MD5_Update(&ctx, challenge, challenge_length);
4175 MD5_Final(*challenge_response, &ctx);
4176
4177 return;
4178 }
4179
4180 static int facility_value(char *name)
4181 {
4182 int i;
4183 for (i = 0; facilitynames[i].c_name; i++)
4184 {
4185 if (strcmp(facilitynames[i].c_name, name) == 0)
4186 return facilitynames[i].c_val;
4187 }
4188 return 0;
4189 }
4190
4191 static void update_config()
4192 {
4193 int i;
4194 char *p;
4195 static int timeout = 0;
4196 static int interval = 0;
4197
4198 // Update logging
4199 closelog();
4200 syslog_log = 0;
4201 if (log_stream)
4202 {
4203 if (log_stream != stderr)
4204 fclose(log_stream);
4205
4206 log_stream = NULL;
4207 }
4208
4209 if (*config->log_filename)
4210 {
4211 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4212 {
4213 char *p = config->log_filename + 7;
4214 if (*p)
4215 {
4216 openlog("l2tpns", LOG_PID, facility_value(p));
4217 syslog_log = 1;
4218 }
4219 }
4220 else if (strchr(config->log_filename, '/') == config->log_filename)
4221 {
4222 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4223 {
4224 fseek(log_stream, 0, SEEK_END);
4225 setbuf(log_stream, NULL);
4226 }
4227 else
4228 {
4229 log_stream = stderr;
4230 setbuf(log_stream, NULL);
4231 }
4232 }
4233 }
4234 else
4235 {
4236 log_stream = stderr;
4237 setbuf(log_stream, NULL);
4238 }
4239
4240 // Update radius
4241 config->numradiusservers = 0;
4242 for (i = 0; i < MAXRADSERVER; i++)
4243 if (config->radiusserver[i])
4244 {
4245 config->numradiusservers++;
4246 // Set radius port: if not set, take the port from the
4247 // first radius server. For the first radius server,
4248 // take the #defined default value from l2tpns.h
4249
4250 // test twice, In case someone works with
4251 // a secondary radius server without defining
4252 // a primary one, this will work even then.
4253 if (i > 0 && !config->radiusport[i])
4254 config->radiusport[i] = config->radiusport[i-1];
4255 if (!config->radiusport[i])
4256 config->radiusport[i] = RADPORT;
4257 }
4258
4259 if (!config->numradiusservers)
4260 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4261
4262 // parse radius_authtypes_s
4263 config->radius_authtypes = config->radius_authprefer = 0;
4264 p = config->radius_authtypes_s;
4265 while (p && *p)
4266 {
4267 char *s = strpbrk(p, " \t,");
4268 int type = 0;
4269
4270 if (s)
4271 {
4272 *s++ = 0;
4273 while (*s == ' ' || *s == '\t')
4274 s++;
4275
4276 if (!*s)
4277 s = 0;
4278 }
4279
4280 if (!strncasecmp("chap", p, strlen(p)))
4281 type = AUTHCHAP;
4282 else if (!strncasecmp("pap", p, strlen(p)))
4283 type = AUTHPAP;
4284 else
4285 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4286
4287 config->radius_authtypes |= type;
4288 if (!config->radius_authprefer)
4289 config->radius_authprefer = type;
4290
4291 p = s;
4292 }
4293
4294 if (!config->radius_authtypes)
4295 {
4296 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4297 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4298 }
4299
4300 // normalise radius_authtypes_s
4301 if (config->radius_authprefer == AUTHPAP)
4302 {
4303 strcpy(config->radius_authtypes_s, "pap");
4304 if (config->radius_authtypes & AUTHCHAP)
4305 strcat(config->radius_authtypes_s, ", chap");
4306 }
4307 else
4308 {
4309 strcpy(config->radius_authtypes_s, "chap");
4310 if (config->radius_authtypes & AUTHPAP)
4311 strcat(config->radius_authtypes_s, ", pap");
4312 }
4313
4314 if (!config->radius_dae_port)
4315 config->radius_dae_port = DAEPORT;
4316
4317 // re-initialise the random number source
4318 initrandom(config->random_device);
4319
4320 // Update plugins
4321 for (i = 0; i < MAXPLUGINS; i++)
4322 {
4323 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4324 continue;
4325
4326 if (*config->plugins[i])
4327 {
4328 // Plugin added
4329 add_plugin(config->plugins[i]);
4330 }
4331 else if (*config->old_plugins[i])
4332 {
4333 // Plugin removed
4334 remove_plugin(config->old_plugins[i]);
4335 }
4336 }
4337
4338 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4339 if (!config->multi_read_count) config->multi_read_count = 10;
4340 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4341 if (!*config->cluster_interface)
4342 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4343
4344 if (!config->cluster_hb_interval)
4345 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4346
4347 if (!config->cluster_hb_timeout)
4348 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4349
4350 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4351 {
4352 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4353 // late, ensure we're sufficiently larger than that
4354 int t = 4 * config->cluster_hb_interval + 11;
4355
4356 if (config->cluster_hb_timeout < t)
4357 {
4358 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4359 config->cluster_hb_timeout = t;
4360 }
4361
4362 // Push timing changes to the slaves immediately if we're the master
4363 if (config->cluster_iam_master)
4364 cluster_heartbeat();
4365
4366 interval = config->cluster_hb_interval;
4367 timeout = config->cluster_hb_timeout;
4368 }
4369
4370 // Write PID file
4371 if (*config->pid_file == '/' && !config->wrote_pid)
4372 {
4373 FILE *f;
4374 if ((f = fopen(config->pid_file, "w")))
4375 {
4376 fprintf(f, "%d\n", getpid());
4377 fclose(f);
4378 config->wrote_pid = 1;
4379 }
4380 else
4381 {
4382 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4383 }
4384 }
4385
4386 config->reload_config = 0;
4387 }
4388
4389 static void read_config_file()
4390 {
4391 FILE *f;
4392
4393 if (!config->config_file) return;
4394 if (!(f = fopen(config->config_file, "r")))
4395 {
4396 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4397 return;
4398 }
4399
4400 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4401 cli_do_file(f);
4402 LOG(3, 0, 0, "Done reading config file\n");
4403 fclose(f);
4404 update_config();
4405 }
4406
4407 int sessionsetup(tunnelidt t, sessionidt s)
4408 {
4409 // A session now exists, set it up
4410 in_addr_t ip;
4411 char *user;
4412 sessionidt i;
4413 int r;
4414
4415 CSTAT(sessionsetup);
4416
4417 LOG(3, s, t, "Doing session setup for session\n");
4418
4419 if (!session[s].ip)
4420 {
4421 assign_ip_address(s);
4422 if (!session[s].ip)
4423 {
4424 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4425 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4426 return 0;
4427 }
4428 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4429 fmtaddr(htonl(session[s].ip), 0));
4430 }
4431
4432
4433 // Make sure this is right
4434 session[s].tunnel = t;
4435
4436 // zap old sessions with same IP and/or username
4437 // Don't kill gardened sessions - doing so leads to a DoS
4438 // from someone who doesn't need to know the password
4439 {
4440 ip = session[s].ip;
4441 user = session[s].user;
4442 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4443 {
4444 if (i == s) continue;
4445 if (!session[s].opened) continue;
4446 if (ip == session[i].ip)
4447 {
4448 sessionkill(i, "Duplicate IP address");
4449 continue;
4450 }
4451
4452 if (config->allow_duplicate_users) continue;
4453 if (session[s].walled_garden || session[i].walled_garden) continue;
4454 if (!strcasecmp(user, session[i].user))
4455 sessionkill(i, "Duplicate session for users");
4456 }
4457 }
4458
4459 {
4460 int routed = 0;
4461
4462 // Add the route for this session.
4463 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4464 {
4465 if ((session[s].ip & session[s].route[r].mask) ==
4466 (session[s].route[r].ip & session[s].route[r].mask))
4467 routed++;
4468
4469 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4470 }
4471
4472 // Static IPs need to be routed if not already
4473 // convered by a Framed-Route. Anything else is part
4474 // of the IP address pool and is already routed, it
4475 // just needs to be added to the IP cache.
4476 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4477 if (session[s].ip_pool_index == -1) // static ip
4478 {
4479 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4480 }
4481 else
4482 cache_ipmap(session[s].ip, s);
4483 }
4484
4485 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4486 lcp_open(t, s); // transition to Network phase and send initial IPCP
4487
4488 // Run the plugin's against this new session.
4489 {
4490 struct param_new_session data = { &tunnel[t], &session[s] };
4491 run_plugins(PLUGIN_NEW_SESSION, &data);
4492 }
4493
4494 // Allocate TBFs if throttled
4495 if (session[s].throttle_in || session[s].throttle_out)
4496 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4497
4498 session[s].last_packet = time_now;
4499
4500 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4501 fmtaddr(htonl(session[s].ip), 0),
4502 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4503
4504 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4505
4506 return 1; // RADIUS OK and IP allocated, done...
4507 }
4508
4509 //
4510 // This session just got dropped on us by the master or something.
4511 // Make sure our tables up up to date...
4512 //
4513 int load_session(sessionidt s, sessiont *new)
4514 {
4515 int i;
4516 int newip = 0;
4517
4518 // Sanity checks.
4519 if (new->ip_pool_index >= MAXIPPOOL ||
4520 new->tunnel >= MAXTUNNEL)
4521 {
4522 LOG(0, s, 0, "Strange session update received!\n");
4523 // FIXME! What to do here?
4524 return 0;
4525 }
4526
4527 //
4528 // Ok. All sanity checks passed. Now we're committed to
4529 // loading the new session.
4530 //
4531
4532 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4533
4534 // See if routes/ip cache need updating
4535 if (new->ip != session[s].ip)
4536 newip++;
4537
4538 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4539 if (new->route[i].ip != session[s].route[i].ip ||
4540 new->route[i].mask != session[s].route[i].mask)
4541 newip++;
4542
4543 // needs update
4544 if (newip)
4545 {
4546 int routed = 0;
4547
4548 // remove old routes...
4549 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4550 {
4551 if ((session[s].ip & session[s].route[i].mask) ==
4552 (session[s].route[i].ip & session[s].route[i].mask))
4553 routed++;
4554
4555 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4556 }
4557
4558 // ...ip
4559 if (session[s].ip)
4560 {
4561 if (session[s].ip_pool_index == -1) // static IP
4562 {
4563 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4564 }
4565 else // It's part of the IP pool, remove it manually.
4566 uncache_ipmap(session[s].ip);
4567 }
4568
4569 routed = 0;
4570
4571 // add new routes...
4572 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4573 {
4574 if ((new->ip & new->route[i].mask) ==
4575 (new->route[i].ip & new->route[i].mask))
4576 routed++;
4577
4578 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4579 }
4580
4581 // ...ip
4582 if (new->ip)
4583 {
4584 // If there's a new one, add it.
4585 if (new->ip_pool_index == -1)
4586 {
4587 if (!routed) routeset(s, new->ip, 0, 0, 1);
4588 }
4589 else
4590 cache_ipmap(new->ip, s);
4591 }
4592 }
4593
4594 // check v6 routing
4595 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4596 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4597
4598 // check filters
4599 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4600 {
4601 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4602 new->filter_in = 0;
4603 }
4604
4605 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4606 {
4607 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4608 new->filter_out = 0;
4609 }
4610
4611 if (new->filter_in != session[s].filter_in)
4612 {
4613 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4614 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4615 }
4616
4617 if (new->filter_out != session[s].filter_out)
4618 {
4619 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4620 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4621 }
4622
4623 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4624 // for walking the sessions to forward byte counts to the master.
4625 config->cluster_highest_sessionid = s;
4626
4627 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4628
4629 // Do fixups into address pool.
4630 if (new->ip_pool_index != -1)
4631 fix_address_pool(s);
4632
4633 return 1;
4634 }
4635
4636 static void initplugins()
4637 {
4638 int i;
4639
4640 loaded_plugins = ll_init();
4641 // Initialize the plugins to nothing
4642 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4643 plugins[i] = ll_init();
4644 }
4645
4646 static void *open_plugin(char *plugin_name, int load)
4647 {
4648 char path[256] = "";
4649
4650 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4651 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4652 return dlopen(path, RTLD_NOW);
4653 }
4654
4655 // plugin callback to get a config value
4656 static void *getconfig(char *key, enum config_typet type)
4657 {
4658 int i;
4659
4660 for (i = 0; config_values[i].key; i++)
4661 {
4662 if (!strcmp(config_values[i].key, key))
4663 {
4664 if (config_values[i].type == type)
4665 return ((void *) config) + config_values[i].offset;
4666
4667 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4668 key, type, config_values[i].type);
4669
4670 return 0;
4671 }
4672 }
4673
4674 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4675 return 0;
4676 }
4677
4678 static int add_plugin(char *plugin_name)
4679 {
4680 static struct pluginfuncs funcs = {
4681 _log,
4682 _log_hex,
4683 fmtaddr,
4684 sessionbyuser,
4685 sessiontbysessionidt,
4686 sessionidtbysessiont,
4687 radiusnew,
4688 radiussend,
4689 getconfig,
4690 sessionshutdown,
4691 sessionkill,
4692 throttle_session,
4693 cluster_send_session,
4694 };
4695
4696 void *p = open_plugin(plugin_name, 1);
4697 int (*initfunc)(struct pluginfuncs *);
4698 int i;
4699
4700 if (!p)
4701 {
4702 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4703 return -1;
4704 }
4705
4706 if (ll_contains(loaded_plugins, p))
4707 {
4708 dlclose(p);
4709 return 0; // already loaded
4710 }
4711
4712 {
4713 int *v = dlsym(p, "plugin_api_version");
4714 if (!v || *v != PLUGIN_API_VERSION)
4715 {
4716 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4717 dlclose(p);
4718 return -1;
4719 }
4720 }
4721
4722 if ((initfunc = dlsym(p, "plugin_init")))
4723 {
4724 if (!initfunc(&funcs))
4725 {
4726 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4727 dlclose(p);
4728 return -1;
4729 }
4730 }
4731
4732 ll_push(loaded_plugins, p);
4733
4734 for (i = 0; i < max_plugin_functions; i++)
4735 {
4736 void *x;
4737 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4738 {
4739 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4740 ll_push(plugins[i], x);
4741 }
4742 }
4743
4744 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4745 return 1;
4746 }
4747
4748 static void run_plugin_done(void *plugin)
4749 {
4750 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4751
4752 if (donefunc)
4753 donefunc();
4754 }
4755
4756 static int remove_plugin(char *plugin_name)
4757 {
4758 void *p = open_plugin(plugin_name, 0);
4759 int loaded = 0;
4760
4761 if (!p)
4762 return -1;
4763
4764 if (ll_contains(loaded_plugins, p))
4765 {
4766 int i;
4767 for (i = 0; i < max_plugin_functions; i++)
4768 {
4769 void *x;
4770 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4771 ll_delete(plugins[i], x);
4772 }
4773
4774 ll_delete(loaded_plugins, p);
4775 run_plugin_done(p);
4776 loaded = 1;
4777 }
4778
4779 dlclose(p);
4780 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4781 return loaded;
4782 }
4783
4784 int run_plugins(int plugin_type, void *data)
4785 {
4786 int (*func)(void *data);
4787
4788 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4789 return PLUGIN_RET_ERROR;
4790
4791 ll_reset(plugins[plugin_type]);
4792 while ((func = ll_next(plugins[plugin_type])))
4793 {
4794 int r = func(data);
4795
4796 if (r != PLUGIN_RET_OK)
4797 return r; // stop here
4798 }
4799
4800 return PLUGIN_RET_OK;
4801 }
4802
4803 static void plugins_done()
4804 {
4805 void *p;
4806
4807 ll_reset(loaded_plugins);
4808 while ((p = ll_next(loaded_plugins)))
4809 run_plugin_done(p);
4810 }
4811
4812 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4813 {
4814 struct nsctl request;
4815 struct nsctl response;
4816 int type = unpack_control(&request, buf, len);
4817 int r;
4818 void *p;
4819
4820 if (log_stream && config->debug >= 4)
4821 {
4822 if (type < 0)
4823 {
4824 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4825 fmtaddr(addr->sin_addr.s_addr, 0), type);
4826 }
4827 else
4828 {
4829 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4830 dump_control(&request, log_stream);
4831 }
4832 }
4833
4834 switch (type)
4835 {
4836 case NSCTL_REQ_LOAD:
4837 if (request.argc != 1)
4838 {
4839 response.type = NSCTL_RES_ERR;
4840 response.argc = 1;
4841 response.argv[0] = "name of plugin required";
4842 }
4843 else if ((r = add_plugin(request.argv[0])) < 1)
4844 {
4845 response.type = NSCTL_RES_ERR;
4846 response.argc = 1;
4847 response.argv[0] = !r
4848 ? "plugin already loaded"
4849 : "error loading plugin";
4850 }
4851 else
4852 {
4853 response.type = NSCTL_RES_OK;
4854 response.argc = 0;
4855 }
4856
4857 break;
4858
4859 case NSCTL_REQ_UNLOAD:
4860 if (request.argc != 1)
4861 {
4862 response.type = NSCTL_RES_ERR;
4863 response.argc = 1;
4864 response.argv[0] = "name of plugin required";
4865 }
4866 else if ((r = remove_plugin(request.argv[0])) < 1)
4867 {
4868 response.type = NSCTL_RES_ERR;
4869 response.argc = 1;
4870 response.argv[0] = !r
4871 ? "plugin not loaded"
4872 : "plugin not found";
4873 }
4874 else
4875 {
4876 response.type = NSCTL_RES_OK;
4877 response.argc = 0;
4878 }
4879
4880 break;
4881
4882 case NSCTL_REQ_HELP:
4883 response.type = NSCTL_RES_OK;
4884 response.argc = 0;
4885
4886 ll_reset(loaded_plugins);
4887 while ((p = ll_next(loaded_plugins)))
4888 {
4889 char **help = dlsym(p, "plugin_control_help");
4890 while (response.argc < 0xff && help && *help)
4891 response.argv[response.argc++] = *help++;
4892 }
4893
4894 break;
4895
4896 case NSCTL_REQ_CONTROL:
4897 {
4898 struct param_control param = {
4899 config->cluster_iam_master,
4900 request.argc,
4901 request.argv,
4902 0,
4903 NULL,
4904 };
4905
4906 int r = run_plugins(PLUGIN_CONTROL, &param);
4907
4908 if (r == PLUGIN_RET_ERROR)
4909 {
4910 response.type = NSCTL_RES_ERR;
4911 response.argc = 1;
4912 response.argv[0] = param.additional
4913 ? param.additional
4914 : "error returned by plugin";
4915 }
4916 else if (r == PLUGIN_RET_NOTMASTER)
4917 {
4918 static char msg[] = "must be run on master: 000.000.000.000";
4919
4920 response.type = NSCTL_RES_ERR;
4921 response.argc = 1;
4922 if (config->cluster_master_address)
4923 {
4924 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4925 response.argv[0] = msg;
4926 }
4927 else
4928 {
4929 response.argv[0] = "must be run on master: none elected";
4930 }
4931 }
4932 else if (!(param.response & NSCTL_RESPONSE))
4933 {
4934 response.type = NSCTL_RES_ERR;
4935 response.argc = 1;
4936 response.argv[0] = param.response
4937 ? "unrecognised response value from plugin"
4938 : "unhandled action";
4939 }
4940 else
4941 {
4942 response.type = param.response;
4943 response.argc = 0;
4944 if (param.additional)
4945 {
4946 response.argc = 1;
4947 response.argv[0] = param.additional;
4948 }
4949 }
4950 }
4951
4952 break;
4953
4954 default:
4955 response.type = NSCTL_RES_ERR;
4956 response.argc = 1;
4957 response.argv[0] = "error unpacking control packet";
4958 }
4959
4960 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4961 if (!buf)
4962 {
4963 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4964 return;
4965 }
4966
4967 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4968 if (r > 0)
4969 {
4970 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4971 if (log_stream && config->debug >= 4)
4972 {
4973 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4974 dump_control(&response, log_stream);
4975 }
4976 }
4977 else
4978 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4979 fmtaddr(addr->sin_addr.s_addr, 0), r);
4980
4981 free(buf);
4982 }
4983
4984 static tunnelidt new_tunnel()
4985 {
4986 tunnelidt i;
4987 for (i = 1; i < MAXTUNNEL; i++)
4988 {
4989 if (tunnel[i].state == TUNNELFREE)
4990 {
4991 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4992 if (i > config->cluster_highest_tunnelid)
4993 config->cluster_highest_tunnelid = i;
4994 return i;
4995 }
4996 }
4997 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4998 return 0;
4999 }
5000
5001 //
5002 // We're becoming the master. Do any required setup..
5003 //
5004 // This is principally telling all the plugins that we're
5005 // now a master, and telling them about all the sessions
5006 // that are active too..
5007 //
5008 void become_master(void)
5009 {
5010 int s, i;
5011 static struct event_data d[RADIUS_FDS];
5012 struct epoll_event e;
5013
5014 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5015
5016 // running a bunch of iptables commands is slow and can cause
5017 // the master to drop tunnels on takeover--kludge around the
5018 // problem by forking for the moment (note: race)
5019 if (!fork_and_close())
5020 {
5021 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5022 {
5023 if (!session[s].opened) // Not an in-use session.
5024 continue;
5025
5026 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5027 }
5028 exit(0);
5029 }
5030
5031 // add radius fds
5032 e.events = EPOLLIN;
5033 for (i = 0; i < RADIUS_FDS; i++)
5034 {
5035 d[i].type = FD_TYPE_RADIUS;
5036 d[i].index = i;
5037 e.data.ptr = &d[i];
5038
5039 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5040 }
5041 }
5042
5043 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5044 {
5045 int s, i;
5046 int count = 0;
5047 int buckets[64];
5048
5049 if (CLI_HELP_REQUESTED)
5050 return CLI_HELP_NO_ARGS;
5051
5052 time(&time_now);
5053 for (i = 0; i < 64;++i) buckets[i] = 0;
5054
5055 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5056 {
5057 int idle;
5058 if (!session[s].opened)
5059 continue;
5060
5061 idle = time_now - session[s].last_packet;
5062 idle /= 5 ; // In multiples of 5 seconds.
5063 if (idle < 0)
5064 idle = 0;
5065 if (idle > 63)
5066 idle = 63;
5067
5068 ++count;
5069 ++buckets[idle];
5070 }
5071
5072 for (i = 0; i < 63; ++i)
5073 {
5074 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5075 }
5076 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5077 cli_print(cli, "%d total sessions open.", count);
5078 return CLI_OK;
5079 }
5080
5081 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5082 {
5083 int s, i;
5084 int count = 0;
5085 int buckets[64];
5086
5087 if (CLI_HELP_REQUESTED)
5088 return CLI_HELP_NO_ARGS;
5089
5090 time(&time_now);
5091 for (i = 0; i < 64;++i) buckets[i] = 0;
5092
5093 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5094 {
5095 int open = 0, d;
5096 if (!session[s].opened)
5097 continue;
5098
5099 d = time_now - session[s].opened;
5100 if (d < 0)
5101 d = 0;
5102 while (d > 1 && open < 32)
5103 {
5104 ++open;
5105 d >>= 1; // half.
5106 }
5107 ++count;
5108 ++buckets[open];
5109 }
5110
5111 s = 1;
5112 for (i = 0; i < 30; ++i)
5113 {
5114 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5115 s <<= 1;
5116 }
5117 cli_print(cli, "%d total sessions open.", count);
5118 return CLI_OK;
5119 }
5120
5121 /* Unhide an avp.
5122 *
5123 * This unencodes the AVP using the L2TP secret and the previously
5124 * stored random vector. It overwrites the hidden data with the
5125 * unhidden AVP subformat.
5126 */
5127 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5128 {
5129 MD5_CTX ctx;
5130 uint8_t digest[16];
5131 uint8_t *last;
5132 size_t d = 0;
5133 uint16_t m = htons(type);
5134
5135 // Compute initial pad
5136 MD5_Init(&ctx);
5137 MD5_Update(&ctx, (unsigned char *) &m, 2);
5138 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5139 MD5_Update(&ctx, vector, vec_len);
5140 MD5_Final(digest, &ctx);
5141
5142 // pointer to last decoded 16 octets
5143 last = value;
5144
5145 while (len > 0)
5146 {
5147 // calculate a new pad based on the last decoded block
5148 if (d >= sizeof(digest))
5149 {
5150 MD5_Init(&ctx);
5151 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5152 MD5_Update(&ctx, last, sizeof(digest));
5153 MD5_Final(digest, &ctx);
5154
5155 d = 0;
5156 last = value;
5157 }
5158
5159 *value++ ^= digest[d++];
5160 len--;
5161 }
5162 }
5163
5164 int find_filter(char const *name, size_t len)
5165 {
5166 int free = -1;
5167 int i;
5168
5169 for (i = 0; i < MAXFILTER; i++)
5170 {
5171 if (!*ip_filters[i].name)
5172 {
5173 if (free < 0)
5174 free = i;
5175
5176 continue;
5177 }
5178
5179 if (strlen(ip_filters[i].name) != len)
5180 continue;
5181
5182 if (!strncmp(ip_filters[i].name, name, len))
5183 return i;
5184 }
5185
5186 return free;
5187 }
5188
5189 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5190 {
5191 switch (p->op)
5192 {
5193 case FILTER_PORT_OP_EQ: return port == p->port;
5194 case FILTER_PORT_OP_NEQ: return port != p->port;
5195 case FILTER_PORT_OP_GT: return port > p->port;
5196 case FILTER_PORT_OP_LT: return port < p->port;
5197 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5198 }
5199
5200 return 0;
5201 }
5202
5203 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5204 {
5205 switch (op)
5206 {
5207 case FILTER_FLAG_OP_ANY:
5208 return (flags & sflags) || (~flags & cflags);
5209
5210 case FILTER_FLAG_OP_ALL:
5211 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5212
5213 case FILTER_FLAG_OP_EST:
5214 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5215 }
5216
5217 return 0;
5218 }
5219
5220 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5221 {
5222 uint16_t frag_offset;
5223 uint8_t proto;
5224 in_addr_t src_ip;
5225 in_addr_t dst_ip;
5226 uint16_t src_port = 0;
5227 uint16_t dst_port = 0;
5228 uint8_t flags = 0;
5229 ip_filter_rulet *rule;
5230
5231 if (len < 20) // up to end of destination address
5232 return 0;
5233
5234 if ((*buf >> 4) != 4) // IPv4
5235 return 0;
5236
5237 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5238 proto = buf[9];
5239 src_ip = *(in_addr_t *) (buf + 12);
5240 dst_ip = *(in_addr_t *) (buf + 16);
5241
5242 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5243 {
5244 int l = (buf[0] & 0xf) * 4; // length of IP header
5245 if (len < l + 4) // ports
5246 return 0;
5247
5248 src_port = ntohs(*(uint16_t *) (buf + l));
5249 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5250 if (proto == IPPROTO_TCP)
5251 {
5252 if (len < l + 14) // flags
5253 return 0;
5254
5255 flags = buf[l + 13] & 0x3f;
5256 }
5257 }
5258
5259 for (rule = ip_filters[filter].rules; rule->action; rule++)
5260 {
5261 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5262 continue;
5263
5264 if (rule->src_wild != INADDR_BROADCAST &&
5265 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5266 continue;
5267
5268 if (rule->dst_wild != INADDR_BROADCAST &&
5269 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5270 continue;
5271
5272 if (frag_offset)
5273 {
5274 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5275 continue;
5276 }
5277 else
5278 {
5279 if (rule->frag)
5280 continue;
5281
5282 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5283 {
5284 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5285 continue;
5286
5287 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5288 continue;
5289
5290 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5291 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5292 continue;
5293 }
5294 }
5295
5296 // matched
5297 rule->counter++;
5298 return rule->action == FILTER_ACTION_PERMIT;
5299 }
5300
5301 // default deny
5302 return 0;
5303 }