6e0c7eec432f68f4a18076e3b4dc3c30190e9fae
[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 1.128 2005/09/02 23:59:56 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
79 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
80
81 static void *ip_hash[256]; // Mapping from IP address to session structures.
82 struct ipv6radix {
83 int sess;
84 struct ipv6radix *branch;
85 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
86
87 // Traffic counters.
88 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
89 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
90 uint32_t eth_tx = 0;
91
92 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
93 time_t time_now = 0; // Current time in seconds since epoch.
94 static char time_now_string[64] = {0}; // Current time as a string.
95 char main_quit = 0; // True if we're in the process of exiting.
96 linked_list *loaded_plugins;
97 linked_list *plugins[MAX_PLUGIN_TYPES];
98
99 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
100 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
101
102 config_descriptt config_values[] = {
103 CONFIG("debug", debug, INT),
104 CONFIG("log_file", log_filename, STRING),
105 CONFIG("pid_file", pid_file, STRING),
106 CONFIG("random_device", random_device, STRING),
107 CONFIG("l2tp_secret", l2tpsecret, STRING),
108 CONFIG("ppp_restart_time", ppp_restart_time, INT),
109 CONFIG("ppp_max_configure", ppp_max_configure, INT),
110 CONFIG("ppp_max_failure", ppp_max_failure, INT),
111 CONFIG("primary_dns", default_dns1, IPv4),
112 CONFIG("secondary_dns", default_dns2, IPv4),
113 CONFIG("primary_radius", radiusserver[0], IPv4),
114 CONFIG("secondary_radius", radiusserver[1], IPv4),
115 CONFIG("primary_radius_port", radiusport[0], SHORT),
116 CONFIG("secondary_radius_port", radiusport[1], SHORT),
117 CONFIG("radius_accounting", radius_accounting, BOOL),
118 CONFIG("radius_interim", radius_interim, INT),
119 CONFIG("radius_secret", radiussecret, STRING),
120 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
121 CONFIG("radius_dae_port", radius_dae_port, SHORT),
122 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
123 CONFIG("bind_address", bind_address, IPv4),
124 CONFIG("peer_address", peer_address, IPv4),
125 CONFIG("send_garp", send_garp, BOOL),
126 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
127 CONFIG("throttle_buckets", num_tbfs, INT),
128 CONFIG("accounting_dir", accounting_dir, STRING),
129 CONFIG("setuid", target_uid, INT),
130 CONFIG("dump_speed", dump_speed, BOOL),
131 CONFIG("multi_read_count", multi_read_count, INT),
132 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
133 CONFIG("lock_pages", lock_pages, BOOL),
134 CONFIG("icmp_rate", icmp_rate, INT),
135 CONFIG("packet_limit", max_packets, INT),
136 CONFIG("cluster_address", cluster_address, IPv4),
137 CONFIG("cluster_interface", cluster_interface, STRING),
138 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
139 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
140 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
141 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
142 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
143 { NULL, 0, 0, 0 },
144 };
145
146 static char *plugin_functions[] = {
147 NULL,
148 "plugin_pre_auth",
149 "plugin_post_auth",
150 "plugin_packet_rx",
151 "plugin_packet_tx",
152 "plugin_timer",
153 "plugin_new_session",
154 "plugin_kill_session",
155 "plugin_control",
156 "plugin_radius_response",
157 "plugin_radius_reset",
158 "plugin_become_master",
159 "plugin_new_session_master",
160 };
161
162 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
163
164 // Counters for shutdown sessions
165 static sessiont shut_acct[8192];
166 static sessionidt shut_acct_n = 0;
167
168 tunnelt *tunnel = NULL; // Array of tunnel structures.
169 sessiont *session = NULL; // Array of session structures.
170 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
171 radiust *radius = NULL; // Array of radius structures.
172 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
173 ip_filtert *ip_filters = NULL; // Array of named filters.
174 static controlt *controlfree = 0;
175 struct Tstats *_statistics = NULL;
176 #ifdef RINGBUFFER
177 struct Tringbuffer *ringbuffer = NULL;
178 #endif
179
180 static void cache_ipmap(in_addr_t ip, int s);
181 static void uncache_ipmap(in_addr_t ip);
182 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
183 static void free_ip_address(sessionidt s);
184 static void dump_acct_info(int all);
185 static void sighup_handler(int sig);
186 static void sigalrm_handler(int sig);
187 static void shutdown_handler(int sig);
188 static void sigchild_handler(int sig);
189 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
190 static void update_config(void);
191 static void read_config_file(void);
192 static void initplugins(void);
193 static int add_plugin(char *plugin_name);
194 static int remove_plugin(char *plugin_name);
195 static void plugins_done(void);
196 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
197 static tunnelidt new_tunnel(void);
198 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
199
200 // on slaves, alow BGP to withdraw cleanly before exiting
201 #define QUIT_DELAY 5
202
203 // quit actions (master)
204 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
205 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
206
207 // return internal time (10ths since process startup), set f if given
208 static clockt now(double *f)
209 {
210 struct timeval t;
211 gettimeofday(&t, 0);
212 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
213 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
214 }
215
216 // work out a retry time based on try number
217 // This is a straight bounded exponential backoff.
218 // Maximum re-try time is 32 seconds. (2^5).
219 clockt backoff(uint8_t try)
220 {
221 if (try > 5) try = 5; // max backoff
222 return now(NULL) + 10 * (1 << try);
223 }
224
225
226 //
227 // Log a debug message. Typically called via the LOG macro
228 //
229 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
230 {
231 static char message[65536] = {0};
232 va_list ap;
233
234 #ifdef RINGBUFFER
235 if (ringbuffer)
236 {
237 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
238 ringbuffer->tail = 0;
239 if (ringbuffer->tail == ringbuffer->head)
240 if (++ringbuffer->head >= RINGBUFFER_SIZE)
241 ringbuffer->head = 0;
242
243 ringbuffer->buffer[ringbuffer->tail].level = level;
244 ringbuffer->buffer[ringbuffer->tail].session = s;
245 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
246 va_start(ap, format);
247 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
248 va_end(ap);
249 }
250 #endif
251
252 if (config->debug < level) return;
253
254 va_start(ap, format);
255 vsnprintf(message, sizeof(message), format, ap);
256
257 if (log_stream)
258 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
259 else if (syslog_log)
260 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
261
262 va_end(ap);
263 }
264
265 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
266 {
267 int i, j;
268 const uint8_t *d = data;
269
270 if (config->debug < level) return;
271
272 // No support for _log_hex to syslog
273 if (log_stream)
274 {
275 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
276 setvbuf(log_stream, NULL, _IOFBF, 16384);
277
278 for (i = 0; i < maxsize; )
279 {
280 fprintf(log_stream, "%4X: ", i);
281 for (j = i; j < maxsize && j < (i + 16); j++)
282 {
283 fprintf(log_stream, "%02X ", d[j]);
284 if (j == i + 7)
285 fputs(": ", log_stream);
286 }
287
288 for (; j < i + 16; j++)
289 {
290 fputs(" ", log_stream);
291 if (j == i + 7)
292 fputs(": ", log_stream);
293 }
294
295 fputs(" ", log_stream);
296 for (j = i; j < maxsize && j < (i + 16); j++)
297 {
298 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
299 fputc(d[j], log_stream);
300 else
301 fputc('.', log_stream);
302
303 if (j == i + 7)
304 fputs(" ", log_stream);
305 }
306
307 i = j;
308 fputs("\n", log_stream);
309 }
310
311 fflush(log_stream);
312 setbuf(log_stream, NULL);
313 }
314 }
315
316 // update a counter, accumulating 2^32 wraps
317 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
318 {
319 uint32_t new = *counter + delta;
320 if (new < *counter)
321 (*wrap)++;
322
323 *counter = new;
324 }
325
326 // initialise the random generator
327 static void initrandom(char *source)
328 {
329 static char path[sizeof(config->random_device)] = "*undefined*";
330
331 // reinitialise only if we are forced to do so or if the config has changed
332 if (source && !strncmp(path, source, sizeof(path)))
333 return;
334
335 // close previous source, if any
336 if (rand_fd >= 0)
337 close(rand_fd);
338
339 rand_fd = -1;
340
341 if (source)
342 {
343 // register changes
344 snprintf(path, sizeof(path), "%s", source);
345
346 if (*path == '/')
347 {
348 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
349 if (rand_fd < 0)
350 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
351 path, strerror(errno));
352 }
353 }
354 }
355
356 // fill buffer with random data
357 void random_data(uint8_t *buf, int len)
358 {
359 int n = 0;
360
361 CSTAT(random_data);
362 if (rand_fd >= 0)
363 {
364 n = read(rand_fd, buf, len);
365 if (n >= len) return;
366 if (n < 0)
367 {
368 if (errno != EAGAIN)
369 {
370 LOG(0, 0, 0, "Error reading from random source: %s\n",
371 strerror(errno));
372
373 // fall back to rand()
374 initrandom(NULL);
375 }
376
377 n = 0;
378 }
379 }
380
381 // append missing data
382 while (n < len)
383 // not using the low order bits from the prng stream
384 buf[n++] = (rand() >> 4) & 0xff;
385 }
386
387 // Add a route
388 //
389 // This adds it to the routing table, advertises it
390 // via BGP if enabled, and stuffs it into the
391 // 'sessionbyip' cache.
392 //
393 // 'ip' and 'mask' must be in _host_ order.
394 //
395 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
396 {
397 struct rtentry r;
398 int i;
399
400 if (!mask) mask = 0xffffffff;
401
402 ip &= mask; // Force the ip to be the first one in the route.
403
404 memset(&r, 0, sizeof(r));
405 r.rt_dev = config->tundevice;
406 r.rt_dst.sa_family = AF_INET;
407 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
408 r.rt_gateway.sa_family = AF_INET;
409 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
410 r.rt_genmask.sa_family = AF_INET;
411 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
412 r.rt_flags = (RTF_UP | RTF_STATIC);
413 if (gw)
414 r.rt_flags |= RTF_GATEWAY;
415 else if (mask == 0xffffffff)
416 r.rt_flags |= RTF_HOST;
417
418 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
419 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
420 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
421
422 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
423 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
424
425 #ifdef BGP
426 if (add)
427 bgp_add_route(htonl(ip), htonl(mask));
428 else
429 bgp_del_route(htonl(ip), htonl(mask));
430 #endif /* BGP */
431
432 // Add/Remove the IPs to the 'sessionbyip' cache.
433 // Note that we add the zero address in the case of
434 // a network route. Roll on CIDR.
435
436 // Note that 's == 0' implies this is the address pool.
437 // We still cache it here, because it will pre-fill
438 // the malloc'ed tree.
439
440 if (s)
441 {
442 if (!add) // Are we deleting a route?
443 s = 0; // Caching the session as '0' is the same as uncaching.
444
445 for (i = ip; (i&mask) == (ip&mask) ; ++i)
446 cache_ipmap(i, s);
447 }
448 }
449
450 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
451 {
452 struct in6_rtmsg rt;
453 char ipv6addr[INET6_ADDRSTRLEN];
454
455 if (ifr6fd < 0)
456 {
457 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
458 return;
459 }
460
461 memset(&rt, 0, sizeof(rt));
462
463 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
464 rt.rtmsg_dst_len = prefixlen;
465 rt.rtmsg_metric = 1;
466 rt.rtmsg_flags = RTF_UP;
467 rt.rtmsg_ifindex = tunidx;
468
469 LOG(1, 0, 0, "Route %s %s/%d\n",
470 add ? "add" : "del",
471 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
472 prefixlen);
473
474 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
475 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
476 strerror(errno));
477
478 // FIXME: need to add BGP routing (RFC2858)
479
480 if (s)
481 {
482 if (!add) // Are we deleting a route?
483 s = 0; // Caching the session as '0' is the same as uncaching.
484
485 cache_ipv6map(ip, prefixlen, s);
486 }
487
488 return;
489 }
490
491 // defined in linux/ipv6.h, but tricky to include from user-space
492 // TODO: move routing to use netlink rather than ioctl
493 struct in6_ifreq {
494 struct in6_addr ifr6_addr;
495 __u32 ifr6_prefixlen;
496 unsigned int ifr6_ifindex;
497 };
498
499 //
500 // Set up TUN interface
501 static void inittun(void)
502 {
503 struct ifreq ifr;
504 struct in6_ifreq ifr6;
505 struct sockaddr_in sin = {0};
506 memset(&ifr, 0, sizeof(ifr));
507 ifr.ifr_flags = IFF_TUN;
508
509 tunfd = open(TUNDEVICE, O_RDWR);
510 if (tunfd < 0)
511 { // fatal
512 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
513 exit(1);
514 }
515 {
516 int flags = fcntl(tunfd, F_GETFL, 0);
517 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
518 }
519 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
520 {
521 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
522 exit(1);
523 }
524 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
525 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
526 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
527
528 sin.sin_family = AF_INET;
529 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
530 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
531
532 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
533 {
534 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
535 exit(1);
536 }
537 /* Bump up the qlen to deal with bursts from the network */
538 ifr.ifr_qlen = 1000;
539 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
540 {
541 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
542 exit(1);
543 }
544 ifr.ifr_flags = IFF_UP;
545 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
546 {
547 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
548 exit(1);
549 }
550 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
551 {
552 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
553 exit(1);
554 }
555 tunidx = ifr.ifr_ifindex;
556
557 // Only setup IPv6 on the tun device if we have a configured prefix
558 if (config->ipv6_prefix.s6_addr[0]) {
559 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
560
561 // Link local address is FE80::1
562 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
563 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
564 ifr6.ifr6_addr.s6_addr[1] = 0x80;
565 ifr6.ifr6_addr.s6_addr[15] = 1;
566 ifr6.ifr6_prefixlen = 64;
567 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
568 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
569 {
570 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
571 " %s\n", strerror(errno));
572 }
573
574 // Global address is prefix::1
575 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
576 ifr6.ifr6_addr = config->ipv6_prefix;
577 ifr6.ifr6_addr.s6_addr[15] = 1;
578 ifr6.ifr6_prefixlen = 64;
579 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
580 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
581 {
582 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
583 strerror(errno));
584 }
585 }
586 }
587
588 // set up UDP ports
589 static void initudp(void)
590 {
591 int on = 1;
592 struct sockaddr_in addr;
593
594 // Tunnel
595 memset(&addr, 0, sizeof(addr));
596 addr.sin_family = AF_INET;
597 addr.sin_port = htons(L2TPPORT);
598 addr.sin_addr.s_addr = config->bind_address;
599 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
600 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
601 {
602 int flags = fcntl(udpfd, F_GETFL, 0);
603 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
604 }
605 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
606 {
607 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
608 exit(1);
609 }
610
611 // Control
612 memset(&addr, 0, sizeof(addr));
613 addr.sin_family = AF_INET;
614 addr.sin_port = htons(NSCTL_PORT);
615 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
616 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
617 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
618 {
619 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
620 exit(1);
621 }
622
623 // Dynamic Authorization Extensions to RADIUS
624 memset(&addr, 0, sizeof(addr));
625 addr.sin_family = AF_INET;
626 addr.sin_port = htons(config->radius_dae_port);
627 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
628 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
629 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
630 {
631 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
632 exit(1);
633 }
634
635 // Intercept
636 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
637 }
638
639 //
640 // Find session by IP, < 1 for not found
641 //
642 // Confusingly enough, this 'ip' must be
643 // in _network_ order. This being the common
644 // case when looking it up from IP packet headers.
645 //
646 // We actually use this cache for two things.
647 // #1. For used IP addresses, this maps to the
648 // session ID that it's used by.
649 // #2. For un-used IP addresses, this maps to the
650 // index into the pool table that contains that
651 // IP address.
652 //
653
654 static int lookup_ipmap(in_addr_t ip)
655 {
656 uint8_t *a = (uint8_t *) &ip;
657 uint8_t **d = (uint8_t **) ip_hash;
658
659 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
660 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
661 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
662
663 return (int) (intptr_t) d[(size_t) *a];
664 }
665
666 static int lookup_ipv6map(struct in6_addr ip)
667 {
668 struct ipv6radix *curnode;
669 int i;
670 int s;
671 char ipv6addr[INET6_ADDRSTRLEN];
672
673 curnode = &ipv6_hash[ip.s6_addr[0]];
674 i = 1;
675 s = curnode->sess;
676
677 while (s == 0 && i < 15 && curnode->branch != NULL)
678 {
679 curnode = &curnode->branch[ip.s6_addr[i]];
680 s = curnode->sess;
681 i++;
682 }
683
684 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
685 inet_ntop(AF_INET6, &ip, ipv6addr,
686 INET6_ADDRSTRLEN),
687 s);
688
689 return s;
690 }
691
692 sessionidt sessionbyip(in_addr_t ip)
693 {
694 int s = lookup_ipmap(ip);
695 CSTAT(sessionbyip);
696
697 if (s > 0 && s < MAXSESSION && session[s].opened)
698 return (sessionidt) s;
699
700 return 0;
701 }
702
703 sessionidt sessionbyipv6(struct in6_addr ip)
704 {
705 int s;
706 CSTAT(sessionbyipv6);
707
708 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
709 (ip.s6_addr[0] == 0xFE &&
710 ip.s6_addr[1] == 0x80 &&
711 ip.s6_addr16[1] == 0 &&
712 ip.s6_addr16[2] == 0 &&
713 ip.s6_addr16[3] == 0)) {
714 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
715 } else {
716 s = lookup_ipv6map(ip);
717 }
718
719 if (s > 0 && s < MAXSESSION && session[s].opened)
720 return s;
721
722 return 0;
723 }
724
725 //
726 // Take an IP address in HOST byte order and
727 // add it to the sessionid by IP cache.
728 //
729 // (It's actually cached in network order)
730 //
731 static void cache_ipmap(in_addr_t ip, int s)
732 {
733 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
734 uint8_t *a = (uint8_t *) &nip;
735 uint8_t **d = (uint8_t **) ip_hash;
736 int i;
737
738 for (i = 0; i < 3; i++)
739 {
740 if (!d[(size_t) a[i]])
741 {
742 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
743 return;
744 }
745
746 d = (uint8_t **) d[(size_t) a[i]];
747 }
748
749 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
750
751 if (s > 0)
752 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
753
754 else if (s == 0)
755 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
756 // else a map to an ip pool index.
757 }
758
759 static void uncache_ipmap(in_addr_t ip)
760 {
761 cache_ipmap(ip, 0); // Assign it to the NULL session.
762 }
763
764 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
765 {
766 int i;
767 int bytes;
768 struct ipv6radix *curnode;
769 char ipv6addr[INET6_ADDRSTRLEN];
770
771 curnode = &ipv6_hash[ip.s6_addr[0]];
772
773 bytes = prefixlen >> 3;
774 i = 1;
775 while (i < bytes) {
776 if (curnode->branch == NULL)
777 {
778 if (!(curnode->branch = calloc(256,
779 sizeof (struct ipv6radix))))
780 return;
781 }
782 curnode = &curnode->branch[ip.s6_addr[i]];
783 i++;
784 }
785
786 curnode->sess = s;
787
788 if (s > 0)
789 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
790 inet_ntop(AF_INET6, &ip, ipv6addr,
791 INET6_ADDRSTRLEN),
792 prefixlen);
793 else if (s == 0)
794 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
795 inet_ntop(AF_INET6, &ip, ipv6addr,
796 INET6_ADDRSTRLEN),
797 prefixlen);
798 }
799
800 //
801 // CLI list to dump current ipcache.
802 //
803 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
804 {
805 char **d = (char **) ip_hash, **e, **f, **g;
806 int i, j, k, l;
807 int count = 0;
808
809 if (CLI_HELP_REQUESTED)
810 return CLI_HELP_NO_ARGS;
811
812 cli_print(cli, "%7s %s", "Sess#", "IP Address");
813
814 for (i = 0; i < 256; ++i)
815 {
816 if (!d[i])
817 continue;
818 e = (char **) d[i];
819 for (j = 0; j < 256; ++j)
820 {
821 if (!e[j])
822 continue;
823 f = (char **) e[j];
824 for (k = 0; k < 256; ++k)
825 {
826 if (!f[k])
827 continue;
828 g = (char **)f[k];
829 for (l = 0; l < 256; ++l)
830 {
831 if (!g[l])
832 continue;
833 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
834 ++count;
835 }
836 }
837 }
838 }
839 cli_print(cli, "%d entries in cache", count);
840 return CLI_OK;
841 }
842
843
844 // Find session by username, 0 for not found
845 // walled garden users aren't authenticated, so the username is
846 // reasonably useless. Ignore them to avoid incorrect actions
847 //
848 // This is VERY inefficent. Don't call it often. :)
849 //
850 sessionidt sessionbyuser(char *username)
851 {
852 int s;
853 CSTAT(sessionbyuser);
854
855 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
856 {
857 if (!session[s].opened)
858 continue;
859
860 if (session[s].walled_garden)
861 continue; // Skip walled garden users.
862
863 if (!strncmp(session[s].user, username, 128))
864 return s;
865
866 }
867 return 0; // Not found.
868 }
869
870 void send_garp(in_addr_t ip)
871 {
872 int s;
873 struct ifreq ifr;
874 uint8_t mac[6];
875
876 s = socket(PF_INET, SOCK_DGRAM, 0);
877 if (s < 0)
878 {
879 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
880 return;
881 }
882 memset(&ifr, 0, sizeof(ifr));
883 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
884 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
885 {
886 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
887 close(s);
888 return;
889 }
890 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
891 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
892 {
893 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
894 close(s);
895 return;
896 }
897 close(s);
898 sendarp(ifr.ifr_ifindex, mac, ip);
899 }
900
901 static sessiont *sessiontbysessionidt(sessionidt s)
902 {
903 if (!s || s >= MAXSESSION) return NULL;
904 return &session[s];
905 }
906
907 static sessionidt sessionidtbysessiont(sessiont *s)
908 {
909 sessionidt val = s-session;
910 if (s < session || val >= MAXSESSION) return 0;
911 return val;
912 }
913
914 // actually send a control message for a specific tunnel
915 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
916 {
917 struct sockaddr_in addr;
918
919 CSTAT(tunnelsend);
920
921 if (!t)
922 {
923 static int backtrace_count = 0;
924 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
925 STAT(tunnel_tx_errors);
926 log_backtrace(backtrace_count, 5)
927 return;
928 }
929
930 if (!tunnel[t].ip)
931 {
932 static int backtrace_count = 0;
933 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
934 log_backtrace(backtrace_count, 5)
935 STAT(tunnel_tx_errors);
936 return;
937 }
938
939 memset(&addr, 0, sizeof(addr));
940 addr.sin_family = AF_INET;
941 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
942 addr.sin_port = htons(tunnel[t].port);
943
944 // sequence expected, if sequence in message
945 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
946
947 // If this is a control message, deal with retries
948 if (*buf & 0x80)
949 {
950 tunnel[t].last = time_now; // control message sent
951 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
952 if (tunnel[t].try > 1)
953 {
954 STAT(tunnel_retries);
955 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
956 }
957 }
958
959 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
960 {
961 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
962 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
963 STAT(tunnel_tx_errors);
964 return;
965 }
966
967 LOG_HEX(5, "Send Tunnel Data", buf, l);
968 STAT(tunnel_tx_packets);
969 INC_STAT(tunnel_tx_bytes, l);
970 }
971
972 //
973 // Tiny helper function to write data to
974 // the 'tun' device.
975 //
976 int tun_write(uint8_t * data, int size)
977 {
978 return write(tunfd, data, size);
979 }
980
981 // process outgoing (to tunnel) IP
982 //
983 static void processipout(uint8_t *buf, int len)
984 {
985 sessionidt s;
986 sessiont *sp;
987 tunnelidt t;
988 in_addr_t ip;
989
990 uint8_t *data = buf; // Keep a copy of the originals.
991 int size = len;
992
993 uint8_t b[MAXETHER + 20];
994
995 CSTAT(processipout);
996
997 if (len < MIN_IP_SIZE)
998 {
999 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1000 STAT(tun_rx_errors);
1001 return;
1002 }
1003 if (len >= MAXETHER)
1004 {
1005 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1006 STAT(tun_rx_errors);
1007 return;
1008 }
1009
1010 // Skip the tun header
1011 buf += 4;
1012 len -= 4;
1013
1014 // Got an IP header now
1015 if (*(uint8_t *)(buf) >> 4 != 4)
1016 {
1017 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1018 return;
1019 }
1020
1021 ip = *(uint32_t *)(buf + 16);
1022 if (!(s = sessionbyip(ip)))
1023 {
1024 // Is this a packet for a session that doesn't exist?
1025 static int rate = 0; // Number of ICMP packets we've sent this second.
1026 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1027
1028 if (last != time_now)
1029 {
1030 last = time_now;
1031 rate = 0;
1032 }
1033
1034 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1035 {
1036 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1037 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1038 config->bind_address ? config->bind_address : my_address, buf, len);
1039 }
1040 return;
1041 }
1042 t = session[s].tunnel;
1043 sp = &session[s];
1044
1045 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1046 if (config->max_packets > 0)
1047 {
1048 if (sess_local[s].last_packet_out == TIME)
1049 {
1050 int max = config->max_packets;
1051
1052 // All packets for throttled sessions are handled by the
1053 // master, so further limit by using the throttle rate.
1054 // A bit of a kludge, since throttle rate is in kbps,
1055 // but should still be generous given our average DSL
1056 // packet size is 200 bytes: a limit of 28kbps equates
1057 // to around 180 packets per second.
1058 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1059 max = sp->throttle_out;
1060
1061 if (++sess_local[s].packets_out > max)
1062 {
1063 sess_local[s].packets_dropped++;
1064 return;
1065 }
1066 }
1067 else
1068 {
1069 if (sess_local[s].packets_dropped)
1070 {
1071 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1072 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1073 sess_local[s].packets_dropped, sess_local[s].packets_out,
1074 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1075 sp->user);
1076 }
1077
1078 sess_local[s].last_packet_out = TIME;
1079 sess_local[s].packets_out = 1;
1080 sess_local[s].packets_dropped = 0;
1081 }
1082 }
1083
1084 // run access-list if any
1085 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1086 return;
1087
1088 if (sp->tbf_out)
1089 {
1090 // Are we throttling this session?
1091 if (config->cluster_iam_master)
1092 tbf_queue_packet(sp->tbf_out, data, size);
1093 else
1094 master_throttle_packet(sp->tbf_out, data, size);
1095 return;
1096 }
1097 else if (sp->walled_garden && !config->cluster_iam_master)
1098 {
1099 // We are walled-gardening this
1100 master_garden_packet(s, data, size);
1101 return;
1102 }
1103
1104 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1105
1106 // Add on L2TP header
1107 {
1108 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1109 if (!p) return;
1110 tunnelsend(b, len + (p-b), t); // send it...
1111 }
1112
1113 // Snooping this session, send it to intercept box
1114 if (sp->snoop_ip && sp->snoop_port)
1115 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1116
1117 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1118 sp->cout_delta += len;
1119 sp->pout++;
1120 udp_tx += len;
1121
1122 sess_local[s].cout += len; // To send to master..
1123 sess_local[s].pout++;
1124 }
1125
1126 // process outgoing (to tunnel) IPv6
1127 //
1128 static void processipv6out(uint8_t * buf, int len)
1129 {
1130 sessionidt s;
1131 sessiont *sp;
1132 tunnelidt t;
1133 in_addr_t ip;
1134 struct in6_addr ip6;
1135
1136 uint8_t *data = buf; // Keep a copy of the originals.
1137 int size = len;
1138
1139 uint8_t b[MAXETHER + 20];
1140
1141 CSTAT(processipv6out);
1142
1143 if (len < MIN_IP_SIZE)
1144 {
1145 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1146 STAT(tunnel_tx_errors);
1147 return;
1148 }
1149 if (len >= MAXETHER)
1150 {
1151 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1152 STAT(tunnel_tx_errors);
1153 return;
1154 }
1155
1156 // Skip the tun header
1157 buf += 4;
1158 len -= 4;
1159
1160 // Got an IP header now
1161 if (*(uint8_t *)(buf) >> 4 != 6)
1162 {
1163 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1164 return;
1165 }
1166
1167 ip6 = *(struct in6_addr *)(buf+24);
1168 s = sessionbyipv6(ip6);
1169
1170 if (s == 0)
1171 {
1172 ip = *(uint32_t *)(buf + 32);
1173 s = sessionbyip(ip);
1174 }
1175
1176 if (s == 0)
1177 {
1178 // Is this a packet for a session that doesn't exist?
1179 static int rate = 0; // Number of ICMP packets we've sent this second.
1180 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1181
1182 if (last != time_now)
1183 {
1184 last = time_now;
1185 rate = 0;
1186 }
1187
1188 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1189 {
1190 // FIXME: Should send icmp6 host unreachable
1191 }
1192 return;
1193 }
1194 t = session[s].tunnel;
1195 sp = &session[s];
1196
1197 // FIXME: add DoS prevention/filters?
1198
1199 if (sp->tbf_out)
1200 {
1201 // Are we throttling this session?
1202 if (config->cluster_iam_master)
1203 tbf_queue_packet(sp->tbf_out, data, size);
1204 else
1205 master_throttle_packet(sp->tbf_out, data, size);
1206 return;
1207 }
1208 else if (sp->walled_garden && !config->cluster_iam_master)
1209 {
1210 // We are walled-gardening this
1211 master_garden_packet(s, data, size);
1212 return;
1213 }
1214
1215 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1216
1217 // Add on L2TP header
1218 {
1219 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1220 if (!p) return;
1221 tunnelsend(b, len + (p-b), t); // send it...
1222 }
1223
1224 // Snooping this session, send it to intercept box
1225 if (sp->snoop_ip && sp->snoop_port)
1226 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1227
1228 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1229 sp->cout_delta += len;
1230 sp->pout++;
1231 udp_tx += len;
1232
1233 sess_local[s].cout += len; // To send to master..
1234 sess_local[s].pout++;
1235 }
1236
1237 //
1238 // Helper routine for the TBF filters.
1239 // Used to send queued data in to the user!
1240 //
1241 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1242 {
1243 sessiont *sp;
1244 tunnelidt t;
1245 in_addr_t ip;
1246
1247 uint8_t b[MAXETHER + 20];
1248
1249 if (len < 0 || len > MAXETHER)
1250 {
1251 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1252 return;
1253 }
1254
1255 // Skip the tun header
1256 buf += 4;
1257 len -= 4;
1258
1259 ip = *(in_addr_t *)(buf + 16);
1260
1261 if (!session[s].ip)
1262 return;
1263
1264 t = session[s].tunnel;
1265 sp = &session[s];
1266
1267 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1268
1269 // Add on L2TP header
1270 {
1271 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1272 if (!p) return;
1273 tunnelsend(b, len + (p-b), t); // send it...
1274 }
1275
1276 // Snooping this session.
1277 if (sp->snoop_ip && sp->snoop_port)
1278 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1279
1280 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1281 sp->cout_delta += len;
1282 sp->pout++;
1283 udp_tx += len;
1284
1285 sess_local[s].cout += len; // To send to master..
1286 sess_local[s].pout++;
1287 }
1288
1289 // add an AVP (16 bit)
1290 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1291 {
1292 uint16_t l = (m ? 0x8008 : 0x0008);
1293 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1294 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1295 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1296 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1297 c->length += 8;
1298 }
1299
1300 // add an AVP (32 bit)
1301 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1302 {
1303 uint16_t l = (m ? 0x800A : 0x000A);
1304 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1305 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1306 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1307 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1308 c->length += 10;
1309 }
1310
1311 // add an AVP (string)
1312 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1313 {
1314 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1315 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1316 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1317 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1318 memcpy(c->buf + c->length + 6, val, strlen(val));
1319 c->length += 6 + strlen(val);
1320 }
1321
1322 // add a binary AVP
1323 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1324 {
1325 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1326 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1327 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1328 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1329 memcpy(c->buf + c->length + 6, val, len);
1330 c->length += 6 + len;
1331 }
1332
1333 // new control connection
1334 static controlt *controlnew(uint16_t mtype)
1335 {
1336 controlt *c;
1337 if (!controlfree)
1338 c = malloc(sizeof(controlt));
1339 else
1340 {
1341 c = controlfree;
1342 controlfree = c->next;
1343 }
1344 assert(c);
1345 c->next = 0;
1346 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1347 c->length = 12;
1348 control16(c, 0, mtype, 1);
1349 return c;
1350 }
1351
1352 // send zero block if nothing is waiting
1353 // (ZLB send).
1354 static void controlnull(tunnelidt t)
1355 {
1356 uint8_t buf[12];
1357 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1358 return;
1359
1360 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1361 *(uint16_t *) (buf + 2) = htons(12); // length
1362 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1363 *(uint16_t *) (buf + 6) = htons(0); // session
1364 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1365 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1366 tunnelsend(buf, 12, t);
1367 }
1368
1369 // add a control message to a tunnel, and send if within window
1370 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1371 {
1372 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1373 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1374 *(uint16_t *) (c->buf + 6) = htons(far); // session
1375 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1376 tunnel[t].ns++; // advance sequence
1377 // link in message in to queue
1378 if (tunnel[t].controlc)
1379 tunnel[t].controle->next = c;
1380 else
1381 tunnel[t].controls = c;
1382
1383 tunnel[t].controle = c;
1384 tunnel[t].controlc++;
1385
1386 // send now if space in window
1387 if (tunnel[t].controlc <= tunnel[t].window)
1388 {
1389 tunnel[t].try = 0; // first send
1390 tunnelsend(c->buf, c->length, t);
1391 }
1392 }
1393
1394 //
1395 // Throttle or Unthrottle a session
1396 //
1397 // Throttle the data from/to through a session to no more than
1398 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1399 // user).
1400 //
1401 // If either value is -1, the current value is retained for that
1402 // direction.
1403 //
1404 void throttle_session(sessionidt s, int rate_in, int rate_out)
1405 {
1406 if (!session[s].opened)
1407 return; // No-one home.
1408
1409 if (!*session[s].user)
1410 return; // User not logged in
1411
1412 if (rate_in >= 0)
1413 {
1414 int bytes = rate_in * 1024 / 8; // kbits to bytes
1415 if (session[s].tbf_in)
1416 free_tbf(session[s].tbf_in);
1417
1418 if (rate_in > 0)
1419 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1420 else
1421 session[s].tbf_in = 0;
1422
1423 session[s].throttle_in = rate_in;
1424 }
1425
1426 if (rate_out >= 0)
1427 {
1428 int bytes = rate_out * 1024 / 8;
1429 if (session[s].tbf_out)
1430 free_tbf(session[s].tbf_out);
1431
1432 if (rate_out > 0)
1433 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1434 else
1435 session[s].tbf_out = 0;
1436
1437 session[s].throttle_out = rate_out;
1438 }
1439 }
1440
1441 // add/remove filters from session (-1 = no change)
1442 void filter_session(sessionidt s, int filter_in, int filter_out)
1443 {
1444 if (!session[s].opened)
1445 return; // No-one home.
1446
1447 if (!*session[s].user)
1448 return; // User not logged in
1449
1450 // paranoia
1451 if (filter_in > MAXFILTER) filter_in = -1;
1452 if (filter_out > MAXFILTER) filter_out = -1;
1453 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1454 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1455
1456 if (filter_in >= 0)
1457 {
1458 if (session[s].filter_in)
1459 ip_filters[session[s].filter_in - 1].used--;
1460
1461 if (filter_in > 0)
1462 ip_filters[filter_in - 1].used++;
1463
1464 session[s].filter_in = filter_in;
1465 }
1466
1467 if (filter_out >= 0)
1468 {
1469 if (session[s].filter_out)
1470 ip_filters[session[s].filter_out - 1].used--;
1471
1472 if (filter_out > 0)
1473 ip_filters[filter_out - 1].used++;
1474
1475 session[s].filter_out = filter_out;
1476 }
1477 }
1478
1479 // start tidy shutdown of session
1480 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1481 {
1482 int walled_garden = session[s].walled_garden;
1483
1484
1485 CSTAT(sessionshutdown);
1486
1487 if (!session[s].opened)
1488 {
1489 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1490 return; // not a live session
1491 }
1492
1493 if (!session[s].die)
1494 {
1495 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1496 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1497 run_plugins(PLUGIN_KILL_SESSION, &data);
1498 }
1499
1500 if (session[s].ip && !walled_garden && !session[s].die)
1501 {
1502 // RADIUS Stop message
1503 uint16_t r = radiusnew(s);
1504 if (r)
1505 {
1506 // stop, if not already trying
1507 if (radius[r].state != RADIUSSTOP)
1508 radiussend(r, RADIUSSTOP);
1509 }
1510 else
1511 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1512
1513 // Save counters to dump to accounting file
1514 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1515 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1516 }
1517
1518 if (session[s].ip)
1519 { // IP allocated, clear and unroute
1520 int r;
1521 int routed = 0;
1522 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1523 {
1524 if ((session[s].ip & session[s].route[r].mask) ==
1525 (session[s].route[r].ip & session[s].route[r].mask))
1526 routed++;
1527
1528 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1529 session[s].route[r].ip = 0;
1530 }
1531
1532 if (session[s].ip_pool_index == -1) // static ip
1533 {
1534 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1535 session[s].ip = 0;
1536 }
1537 else
1538 free_ip_address(s);
1539
1540 // unroute IPv6, if setup
1541 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1542 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1543 }
1544
1545 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1546 throttle_session(s, 0, 0);
1547
1548 if (result)
1549 { // Send CDN
1550 controlt *c = controlnew(14); // sending CDN
1551 if (error)
1552 {
1553 uint8_t buf[4];
1554 *(uint16_t *) buf = htons(result);
1555 *(uint16_t *) (buf+2) = htons(error);
1556 controlb(c, 1, buf, 4, 1);
1557 }
1558 else
1559 control16(c, 1, result, 1);
1560
1561 control16(c, 14, s, 1); // assigned session (our end)
1562 controladd(c, session[s].far, session[s].tunnel); // send the message
1563 }
1564
1565 if (!session[s].die)
1566 session[s].die = TIME + 150; // Clean up in 15 seconds
1567
1568 // update filter refcounts
1569 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1570 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1571
1572 // clear PPP state
1573 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1574 sess_local[s].lcp.restart = 0;
1575 sess_local[s].ipcp.restart = 0;
1576 sess_local[s].ipv6cp.restart = 0;
1577 sess_local[s].ccp.restart = 0;
1578
1579 cluster_send_session(s);
1580 }
1581
1582 void sendipcp(sessionidt s, tunnelidt t)
1583 {
1584 uint8_t buf[MAXETHER];
1585 uint8_t *q;
1586
1587 CSTAT(sendipcp);
1588 LOG(3, s, t, "IPCP: send ConfigReq\n");
1589
1590 if (!session[s].unique_id)
1591 {
1592 if (!++last_id) ++last_id; // skip zero
1593 session[s].unique_id = last_id;
1594 }
1595
1596 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP);
1597 if (!q) return;
1598
1599 *q = ConfigReq;
1600 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1601 *(uint16_t *) (q + 2) = htons(10); // packet length
1602 q[4] = 3; // ip address option
1603 q[5] = 6; // option length
1604 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1605 config->bind_address ? config->bind_address :
1606 my_address; // send my IP
1607
1608 tunnelsend(buf, 10 + (q - buf), t); // send it
1609 }
1610
1611 void sendipv6cp(sessionidt s, tunnelidt t)
1612 {
1613 uint8_t buf[MAXETHER];
1614 uint8_t *q;
1615
1616 CSTAT(sendipv6cp);
1617 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1618
1619 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1620 if (!q) return;
1621
1622 *q = ConfigReq;
1623 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1624 // only send one type
1625 // of request
1626 *(uint16_t *) (q + 2) = htons(14);
1627 q[4] = 1; // interface identifier option
1628 q[5] = 10; // option length
1629 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1630 *(uint32_t *) (q + 10) = 0;
1631 q[13] = 1;
1632
1633 tunnelsend(buf, 14 + (q - buf), t); // send it
1634 }
1635
1636 static void sessionclear(sessionidt s)
1637 {
1638 memset(&session[s], 0, sizeof(session[s]));
1639 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1640 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1641
1642 session[s].tunnel = T_FREE; // Mark it as free.
1643 session[s].next = sessionfree;
1644 sessionfree = s;
1645 }
1646
1647 // kill a session now
1648 void sessionkill(sessionidt s, char *reason)
1649 {
1650
1651 CSTAT(sessionkill);
1652
1653 if (!session[s].opened) // not alive
1654 return;
1655
1656 if (session[s].next)
1657 {
1658 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1659 return;
1660 }
1661
1662 session[s].die = TIME;
1663 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1664 if (sess_local[s].radius)
1665 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1666
1667 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1668 sessionclear(s);
1669 cluster_send_session(s);
1670 }
1671
1672 static void tunnelclear(tunnelidt t)
1673 {
1674 if (!t) return;
1675 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1676 tunnel[t].state = TUNNELFREE;
1677 }
1678
1679 // kill a tunnel now
1680 static void tunnelkill(tunnelidt t, char *reason)
1681 {
1682 sessionidt s;
1683 controlt *c;
1684
1685 CSTAT(tunnelkill);
1686
1687 tunnel[t].state = TUNNELDIE;
1688
1689 // free control messages
1690 while ((c = tunnel[t].controls))
1691 {
1692 controlt * n = c->next;
1693 tunnel[t].controls = n;
1694 tunnel[t].controlc--;
1695 c->next = controlfree;
1696 controlfree = c;
1697 }
1698 // kill sessions
1699 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1700 if (session[s].tunnel == t)
1701 sessionkill(s, reason);
1702
1703 // free tunnel
1704 tunnelclear(t);
1705 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1706 cli_tunnel_actions[t].action = 0;
1707 cluster_send_tunnel(t);
1708 }
1709
1710 // shut down a tunnel cleanly
1711 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1712 {
1713 sessionidt s;
1714
1715 CSTAT(tunnelshutdown);
1716
1717 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1718 {
1719 // never set up, can immediately kill
1720 tunnelkill(t, reason);
1721 return;
1722 }
1723 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1724
1725 // close session
1726 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1727 if (session[s].tunnel == t)
1728 sessionshutdown(s, reason, 0, 0);
1729
1730 tunnel[t].state = TUNNELDIE;
1731 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1732 cluster_send_tunnel(t);
1733 // TBA - should we wait for sessions to stop?
1734 if (result)
1735 {
1736 controlt *c = controlnew(4); // sending StopCCN
1737 if (error)
1738 {
1739 uint8_t buf[64];
1740 int l = 4;
1741 *(uint16_t *) buf = htons(result);
1742 *(uint16_t *) (buf+2) = htons(error);
1743 if (msg)
1744 {
1745 int m = strlen(msg);
1746 if (m + 4 > sizeof(buf))
1747 m = sizeof(buf) - 4;
1748
1749 memcpy(buf+4, msg, m);
1750 l += m;
1751 }
1752
1753 controlb(c, 1, buf, l, 1);
1754 }
1755 else
1756 control16(c, 1, result, 1);
1757
1758 control16(c, 9, t, 1); // assigned tunnel (our end)
1759 controladd(c, 0, t); // send the message
1760 }
1761 }
1762
1763 // read and process packet on tunnel (UDP)
1764 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1765 {
1766 uint8_t *chapresponse = NULL;
1767 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1768 uint8_t *p = buf + 2;
1769
1770
1771 CSTAT(processudp);
1772
1773 udp_rx += len;
1774 udp_rx_pkt++;
1775 LOG_HEX(5, "UDP Data", buf, len);
1776 STAT(tunnel_rx_packets);
1777 INC_STAT(tunnel_rx_bytes, len);
1778 if (len < 6)
1779 {
1780 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1781 STAT(tunnel_rx_errors);
1782 return;
1783 }
1784 if ((buf[1] & 0x0F) != 2)
1785 {
1786 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1787 STAT(tunnel_rx_errors);
1788 return;
1789 }
1790 if (*buf & 0x40)
1791 { // length
1792 l = ntohs(*(uint16_t *) p);
1793 p += 2;
1794 }
1795 t = ntohs(*(uint16_t *) p);
1796 p += 2;
1797 s = ntohs(*(uint16_t *) p);
1798 p += 2;
1799 if (s >= MAXSESSION)
1800 {
1801 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1802 STAT(tunnel_rx_errors);
1803 return;
1804 }
1805 if (t >= MAXTUNNEL)
1806 {
1807 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1808 STAT(tunnel_rx_errors);
1809 return;
1810 }
1811 if (*buf & 0x08)
1812 { // ns/nr
1813 ns = ntohs(*(uint16_t *) p);
1814 p += 2;
1815 nr = ntohs(*(uint16_t *) p);
1816 p += 2;
1817 }
1818 if (*buf & 0x02)
1819 { // offset
1820 uint16_t o = ntohs(*(uint16_t *) p);
1821 p += o + 2;
1822 }
1823 if ((p - buf) > l)
1824 {
1825 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1826 STAT(tunnel_rx_errors);
1827 return;
1828 }
1829 l -= (p - buf);
1830 if (*buf & 0x80)
1831 { // control
1832 uint16_t message = 0xFFFF; // message type
1833 uint8_t fatal = 0;
1834 uint8_t mandatory = 0;
1835 uint16_t asession = 0; // assigned session
1836 uint32_t amagic = 0; // magic number
1837 uint8_t aflags = 0; // flags from last LCF
1838 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1839 char called[MAXTEL] = ""; // called number
1840 char calling[MAXTEL] = ""; // calling number
1841
1842 if (!config->cluster_iam_master)
1843 {
1844 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1845 return;
1846 }
1847
1848 // control messages must have bits 0x80|0x40|0x08
1849 // (type, length and sequence) set, and bits 0x02|0x01
1850 // (offset and priority) clear
1851 if ((*buf & 0xCB) != 0xC8)
1852 {
1853 LOG(1, s, t, "Bad control header %02X\n", *buf);
1854 STAT(tunnel_rx_errors);
1855 return;
1856 }
1857
1858 // check for duplicate tunnel open message
1859 if (!t && ns == 0)
1860 {
1861 int i;
1862
1863 //
1864 // Is this a duplicate of the first packet? (SCCRQ)
1865 //
1866 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1867 {
1868 if (tunnel[i].state != TUNNELOPENING ||
1869 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1870 tunnel[i].port != ntohs(addr->sin_port) )
1871 continue;
1872 t = i;
1873 LOG(3, s, t, "Duplicate SCCRQ?\n");
1874 break;
1875 }
1876 }
1877
1878 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1879 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1880
1881 // if no tunnel specified, assign one
1882 if (!t)
1883 {
1884 if (!(t = new_tunnel()))
1885 {
1886 LOG(1, 0, 0, "No more tunnels\n");
1887 STAT(tunnel_overflow);
1888 return;
1889 }
1890 tunnelclear(t);
1891 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1892 tunnel[t].port = ntohs(addr->sin_port);
1893 tunnel[t].window = 4; // default window
1894 STAT(tunnel_created);
1895 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1896 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1897 }
1898
1899 // If the 'ns' just received is not the 'nr' we're
1900 // expecting, just send an ack and drop it.
1901 //
1902 // if 'ns' is less, then we got a retransmitted packet.
1903 // if 'ns' is greater than missed a packet. Either way
1904 // we should ignore it.
1905 if (ns != tunnel[t].nr)
1906 {
1907 // is this the sequence we were expecting?
1908 STAT(tunnel_rx_errors);
1909 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1910 t, ns, tunnel[t].nr);
1911
1912 if (l) // Is this not a ZLB?
1913 controlnull(t);
1914 return;
1915 }
1916
1917 // This is used to time out old tunnels
1918 tunnel[t].lastrec = time_now;
1919
1920 // check sequence of this message
1921 {
1922 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1923 // some to clear maybe?
1924 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1925 {
1926 controlt *c = tunnel[t].controls;
1927 tunnel[t].controls = c->next;
1928 tunnel[t].controlc--;
1929 c->next = controlfree;
1930 controlfree = c;
1931 skip--;
1932 tunnel[t].try = 0; // we have progress
1933 }
1934
1935 // receiver advance (do here so quoted correctly in any sends below)
1936 if (l) tunnel[t].nr = (ns + 1);
1937 if (skip < 0) skip = 0;
1938 if (skip < tunnel[t].controlc)
1939 {
1940 // some control packets can now be sent that were previous stuck out of window
1941 int tosend = tunnel[t].window - skip;
1942 controlt *c = tunnel[t].controls;
1943 while (c && skip)
1944 {
1945 c = c->next;
1946 skip--;
1947 }
1948 while (c && tosend)
1949 {
1950 tunnel[t].try = 0; // first send
1951 tunnelsend(c->buf, c->length, t);
1952 c = c->next;
1953 tosend--;
1954 }
1955 }
1956 if (!tunnel[t].controlc)
1957 tunnel[t].retry = 0; // caught up
1958 }
1959 if (l)
1960 { // if not a null message
1961 int result = 0;
1962 int error = 0;
1963 char *msg = 0;
1964
1965 // process AVPs
1966 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1967 {
1968 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1969 uint8_t *b = p;
1970 uint8_t flags = *p;
1971 uint16_t mtype;
1972 if (n > l)
1973 {
1974 LOG(1, s, t, "Invalid length in AVP\n");
1975 STAT(tunnel_rx_errors);
1976 return;
1977 }
1978 p += n; // next
1979 l -= n;
1980 if (flags & 0x3C) // reserved bits, should be clear
1981 {
1982 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1983 fatal = flags;
1984 result = 2; // general error
1985 error = 3; // reserved field non-zero
1986 msg = 0;
1987 continue; // next
1988 }
1989 b += 2;
1990 if (*(uint16_t *) (b))
1991 {
1992 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1993 fatal = flags;
1994 result = 2; // general error
1995 error = 6; // generic vendor-specific error
1996 msg = "unsupported vendor-specific";
1997 continue; // next
1998 }
1999 b += 2;
2000 mtype = ntohs(*(uint16_t *) (b));
2001 b += 2;
2002 n -= 6;
2003
2004 if (flags & 0x40)
2005 {
2006 uint16_t orig_len;
2007
2008 // handle hidden AVPs
2009 if (!*config->l2tpsecret)
2010 {
2011 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2012 fatal = flags;
2013 result = 2; // general error
2014 error = 6; // generic vendor-specific error
2015 msg = "secret not specified";
2016 continue;
2017 }
2018 if (!session[s].random_vector_length)
2019 {
2020 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2021 fatal = flags;
2022 result = 2; // general error
2023 error = 6; // generic
2024 msg = "no random vector";
2025 continue;
2026 }
2027 if (n < 8)
2028 {
2029 LOG(2, s, t, "Short hidden AVP.\n");
2030 fatal = flags;
2031 result = 2; // general error
2032 error = 2; // length is wrong
2033 msg = 0;
2034 continue;
2035 }
2036
2037 // Unhide the AVP
2038 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2039
2040 orig_len = ntohs(*(uint16_t *) b);
2041 if (orig_len > n + 2)
2042 {
2043 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2044 orig_len, n);
2045
2046 fatal = flags;
2047 result = 2; // general error
2048 error = 2; // length is wrong
2049 msg = 0;
2050 continue;
2051 }
2052
2053 b += 2;
2054 n = orig_len;
2055 }
2056
2057 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2058 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2059
2060 switch (mtype)
2061 {
2062 case 0: // message type
2063 message = ntohs(*(uint16_t *) b);
2064 mandatory = flags & 0x80;
2065 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2066 break;
2067 case 1: // result code
2068 {
2069 uint16_t rescode = ntohs(*(uint16_t *) b);
2070 const char* resdesc = "(unknown)";
2071 if (message == 4)
2072 { /* StopCCN */
2073 resdesc = l2tp_stopccn_result_code(rescode);
2074 }
2075 else if (message == 14)
2076 { /* CDN */
2077 resdesc = l2tp_cdn_result_code(rescode);
2078 }
2079
2080 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2081 if (n >= 4)
2082 {
2083 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2084 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2085 }
2086 if (n > 4)
2087 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2088
2089 break;
2090 }
2091 break;
2092 case 2: // protocol version
2093 {
2094 version = ntohs(*(uint16_t *) (b));
2095 LOG(4, s, t, " Protocol version = %d\n", version);
2096 if (version && version != 0x0100)
2097 { // allow 0.0 and 1.0
2098 LOG(1, s, t, " Bad protocol version %04X\n", version);
2099 fatal = flags;
2100 result = 5; // unspported protocol version
2101 error = 0x0100; // supported version
2102 msg = 0;
2103 continue; // next
2104 }
2105 }
2106 break;
2107 case 3: // framing capabilities
2108 // LOG(4, s, t, "Framing capabilities\n");
2109 break;
2110 case 4: // bearer capabilities
2111 // LOG(4, s, t, "Bearer capabilities\n");
2112 break;
2113 case 5: // tie breaker
2114 // We never open tunnels, so we don't care about tie breakers
2115 // LOG(4, s, t, "Tie breaker\n");
2116 continue;
2117 case 6: // firmware revision
2118 // LOG(4, s, t, "Firmware revision\n");
2119 break;
2120 case 7: // host name
2121 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2122 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2123 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2124 // TBA - to send to RADIUS
2125 break;
2126 case 8: // vendor name
2127 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2128 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2129 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2130 break;
2131 case 9: // assigned tunnel
2132 tunnel[t].far = ntohs(*(uint16_t *) (b));
2133 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2134 break;
2135 case 10: // rx window
2136 tunnel[t].window = ntohs(*(uint16_t *) (b));
2137 if (!tunnel[t].window)
2138 tunnel[t].window = 1; // window of 0 is silly
2139 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2140 break;
2141 case 11: // Challenge
2142 {
2143 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2144 build_chap_response(b, 2, n, &chapresponse);
2145 }
2146 break;
2147 case 13: // Response
2148 // Why did they send a response? We never challenge.
2149 LOG(2, s, t, " received unexpected challenge response\n");
2150 break;
2151
2152 case 14: // assigned session
2153 asession = session[s].far = ntohs(*(uint16_t *) (b));
2154 LOG(4, s, t, " assigned session = %d\n", asession);
2155 break;
2156 case 15: // call serial number
2157 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2158 break;
2159 case 18: // bearer type
2160 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2161 // TBA - for RADIUS
2162 break;
2163 case 19: // framing type
2164 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2165 // TBA
2166 break;
2167 case 21: // called number
2168 memset(called, 0, sizeof(called));
2169 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2170 LOG(4, s, t, " Called <%s>\n", called);
2171 break;
2172 case 22: // calling number
2173 memset(calling, 0, sizeof(calling));
2174 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2175 LOG(4, s, t, " Calling <%s>\n", calling);
2176 break;
2177 case 23: // subtype
2178 break;
2179 case 24: // tx connect speed
2180 if (n == 4)
2181 {
2182 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2183 }
2184 else
2185 {
2186 // AS5300s send connect speed as a string
2187 char tmp[30];
2188 memset(tmp, 0, sizeof(tmp));
2189 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2190 session[s].tx_connect_speed = atol(tmp);
2191 }
2192 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2193 break;
2194 case 38: // rx connect speed
2195 if (n == 4)
2196 {
2197 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2198 }
2199 else
2200 {
2201 // AS5300s send connect speed as a string
2202 char tmp[30];
2203 memset(tmp, 0, sizeof(tmp));
2204 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2205 session[s].rx_connect_speed = atol(tmp);
2206 }
2207 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2208 break;
2209 case 25: // Physical Channel ID
2210 {
2211 uint32_t tmp = ntohl(*(uint32_t *) b);
2212 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2213 break;
2214 }
2215 case 29: // Proxy Authentication Type
2216 {
2217 uint16_t atype = ntohs(*(uint16_t *)b);
2218 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2219 break;
2220 }
2221 case 30: // Proxy Authentication Name
2222 {
2223 char authname[64];
2224 memset(authname, 0, sizeof(authname));
2225 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2226 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2227 authname);
2228 break;
2229 }
2230 case 31: // Proxy Authentication Challenge
2231 {
2232 LOG(4, s, t, " Proxy Auth Challenge\n");
2233 break;
2234 }
2235 case 32: // Proxy Authentication ID
2236 {
2237 uint16_t authid = ntohs(*(uint16_t *)(b));
2238 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2239 break;
2240 }
2241 case 33: // Proxy Authentication Response
2242 LOG(4, s, t, " Proxy Auth Response\n");
2243 break;
2244 case 27: // last sent lcp
2245 { // find magic number
2246 uint8_t *p = b, *e = p + n;
2247 while (p + 1 < e && p[1] && p + p[1] <= e)
2248 {
2249 if (*p == 5 && p[1] == 6) // Magic-Number
2250 amagic = ntohl(*(uint32_t *) (p + 2));
2251 else if (*p == 7) // Protocol-Field-Compression
2252 aflags |= SESSIONPFC;
2253 else if (*p == 8) // Address-and-Control-Field-Compression
2254 aflags |= SESSIONACFC;
2255 p += p[1];
2256 }
2257 }
2258 break;
2259 case 28: // last recv lcp confreq
2260 break;
2261 case 26: // Initial Received LCP CONFREQ
2262 break;
2263 case 39: // seq required - we control it as an LNS anyway...
2264 break;
2265 case 36: // Random Vector
2266 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2267 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2268 if (n > sizeof(session[s].random_vector))
2269 n = sizeof(session[s].random_vector);
2270 memcpy(session[s].random_vector, b, n);
2271 session[s].random_vector_length = n;
2272 break;
2273 default:
2274 {
2275 static char e[] = "unknown AVP 0xXXXX";
2276 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2277 fatal = flags;
2278 result = 2; // general error
2279 error = 8; // unknown mandatory AVP
2280 sprintf((msg = e) + 14, "%04x", mtype);
2281 continue; // next
2282 }
2283 }
2284 }
2285 // process message
2286 if (fatal & 0x80)
2287 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2288 else
2289 switch (message)
2290 {
2291 case 1: // SCCRQ - Start Control Connection Request
2292 tunnel[t].state = TUNNELOPENING;
2293 if (main_quit != QUIT_SHUTDOWN)
2294 {
2295 controlt *c = controlnew(2); // sending SCCRP
2296 control16(c, 2, version, 1); // protocol version
2297 control32(c, 3, 3, 1); // framing
2298 controls(c, 7, hostname, 1); // host name
2299 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2300 control16(c, 9, t, 1); // assigned tunnel
2301 controladd(c, 0, t); // send the resply
2302 }
2303 else
2304 {
2305 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2306 }
2307 break;
2308 case 2: // SCCRP
2309 tunnel[t].state = TUNNELOPEN;
2310 break;
2311 case 3: // SCCN
2312 tunnel[t].state = TUNNELOPEN;
2313 controlnull(t); // ack
2314 break;
2315 case 4: // StopCCN
2316 controlnull(t); // ack
2317 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2318 break;
2319 case 6: // HELLO
2320 controlnull(t); // simply ACK
2321 break;
2322 case 7: // OCRQ
2323 // TBA
2324 break;
2325 case 8: // OCRO
2326 // TBA
2327 break;
2328 case 9: // OCCN
2329 // TBA
2330 break;
2331 case 10: // ICRQ
2332 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2333 {
2334 controlt *c = controlnew(11); // ICRP
2335
2336 s = sessionfree;
2337 sessionfree = session[s].next;
2338 memset(&session[s], 0, sizeof(session[s]));
2339
2340 if (s > config->cluster_highest_sessionid)
2341 config->cluster_highest_sessionid = s;
2342
2343 session[s].opened = time_now;
2344 session[s].tunnel = t;
2345 session[s].far = asession;
2346 session[s].last_packet = time_now;
2347 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2348 control16(c, 14, s, 1); // assigned session
2349 controladd(c, asession, t); // send the reply
2350
2351 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2352 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2353
2354 session[s].ppp.phase = Establish;
2355 session[s].ppp.lcp = Starting;
2356
2357 STAT(session_created);
2358 break;
2359 }
2360
2361 {
2362 controlt *c = controlnew(14); // CDN
2363 if (!sessionfree)
2364 {
2365 STAT(session_overflow);
2366 LOG(1, 0, t, "No free sessions\n");
2367 control16(c, 1, 4, 0); // temporary lack of resources
2368 }
2369 else
2370 control16(c, 1, 2, 7); // shutting down, try another
2371
2372 controladd(c, asession, t); // send the message
2373 }
2374 return;
2375 case 11: // ICRP
2376 // TBA
2377 break;
2378 case 12: // ICCN
2379 if (amagic == 0) amagic = time_now;
2380 session[s].magic = amagic; // set magic number
2381 session[s].l2tp_flags = aflags; // set flags received
2382 session[s].mru = DEFAULT_MRU;
2383 controlnull(t); // ack
2384
2385 // start LCP
2386 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2387 sess_local[s].lcp.conf_sent = 1;
2388 sess_local[s].lcp.nak_sent = 0;
2389 sess_local[s].lcp_authtype = config->radius_authprefer;
2390 session[s].ppp.lcp = RequestSent;
2391 sendlcp(s, t);
2392
2393 break;
2394 case 14: // CDN
2395 controlnull(t); // ack
2396 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2397 break;
2398 case 0xFFFF:
2399 LOG(1, s, t, "Missing message type\n");
2400 break;
2401 default:
2402 STAT(tunnel_rx_errors);
2403 if (mandatory)
2404 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2405 else
2406 LOG(1, s, t, "Unknown message type %d\n", message);
2407 break;
2408 }
2409 if (chapresponse) free(chapresponse);
2410 cluster_send_tunnel(t);
2411 }
2412 else
2413 {
2414 LOG(4, s, t, " Got a ZLB ack\n");
2415 }
2416 }
2417 else
2418 { // data
2419 uint16_t prot;
2420
2421 LOG_HEX(5, "Receive Tunnel Data", p, l);
2422 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2423 { // HDLC address header, discard
2424 p += 2;
2425 l -= 2;
2426 }
2427 if (l < 2)
2428 {
2429 LOG(1, s, t, "Short ppp length %d\n", l);
2430 STAT(tunnel_rx_errors);
2431 return;
2432 }
2433 if (*p & 1)
2434 {
2435 prot = *p++;
2436 l--;
2437 }
2438 else
2439 {
2440 prot = ntohs(*(uint16_t *) p);
2441 p += 2;
2442 l -= 2;
2443 }
2444
2445 if (s && !session[s].opened) // Is something wrong??
2446 {
2447 if (!config->cluster_iam_master)
2448 {
2449 // Pass it off to the master to deal with..
2450 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2451 return;
2452 }
2453
2454
2455 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2456 STAT(tunnel_rx_errors);
2457 return;
2458 }
2459
2460 if (prot == PPPPAP)
2461 {
2462 session[s].last_packet = time_now;
2463 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2464 processpap(s, t, p, l);
2465 }
2466 else if (prot == PPPCHAP)
2467 {
2468 session[s].last_packet = time_now;
2469 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2470 processchap(s, t, p, l);
2471 }
2472 else if (prot == PPPLCP)
2473 {
2474 session[s].last_packet = time_now;
2475 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2476 processlcp(s, t, p, l);
2477 }
2478 else if (prot == PPPIPCP)
2479 {
2480 session[s].last_packet = time_now;
2481 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2482 processipcp(s, t, p, l);
2483 }
2484 else if (prot == PPPIPV6CP)
2485 {
2486 session[s].last_packet = time_now;
2487 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2488 processipv6cp(s, t, p, l);
2489 }
2490 else if (prot == PPPCCP)
2491 {
2492 session[s].last_packet = time_now;
2493 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2494 processccp(s, t, p, l);
2495 }
2496 else if (prot == PPPIP)
2497 {
2498 if (session[s].die)
2499 {
2500 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2501 return; // closing session, PPP not processed
2502 }
2503
2504 session[s].last_packet = time_now;
2505 if (session[s].walled_garden && !config->cluster_iam_master)
2506 {
2507 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2508 return;
2509 }
2510
2511 processipin(s, t, p, l);
2512 }
2513 else if (prot == PPPIPV6)
2514 {
2515 if (!config->ipv6_prefix.s6_addr[0])
2516 {
2517 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2518 return;
2519 }
2520 if (session[s].die)
2521 {
2522 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2523 return; // closing session, PPP not processed
2524 }
2525
2526 session[s].last_packet = time_now;
2527 if (session[s].walled_garden && !config->cluster_iam_master)
2528 {
2529 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2530 return;
2531 }
2532
2533 processipv6in(s, t, p, l);
2534 }
2535 else
2536 {
2537 STAT(tunnel_rx_errors);
2538 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2539 }
2540 }
2541 }
2542
2543 // read and process packet on tun
2544 static void processtun(uint8_t * buf, int len)
2545 {
2546 LOG_HEX(5, "Receive TUN Data", buf, len);
2547 STAT(tun_rx_packets);
2548 INC_STAT(tun_rx_bytes, len);
2549
2550 CSTAT(processtun);
2551
2552 eth_rx_pkt++;
2553 eth_rx += len;
2554 if (len < 22)
2555 {
2556 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2557 STAT(tun_rx_errors);
2558 return;
2559 }
2560
2561 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2562 processipout(buf, len);
2563 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2564 && config->ipv6_prefix.s6_addr[0])
2565 processipv6out(buf, len);
2566
2567 // Else discard.
2568 }
2569
2570 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2571 // that we look at the whole of the tunnel, radius and session tables
2572 // every second
2573 static void regular_cleanups(double period)
2574 {
2575 // Next tunnel, radius and session to check for actions on.
2576 static tunnelidt t = 0;
2577 static int r = 0;
2578 static sessionidt s = 0;
2579
2580 int t_actions = 0;
2581 int r_actions = 0;
2582 int s_actions = 0;
2583
2584 int t_slice;
2585 int r_slice;
2586 int s_slice;
2587
2588 int i;
2589 int a;
2590
2591 // divide up tables into slices based on the last run
2592 t_slice = config->cluster_highest_tunnelid * period;
2593 r_slice = (MAXRADIUS - 1) * period;
2594 s_slice = config->cluster_highest_sessionid * period;
2595
2596 if (t_slice < 1)
2597 t_slice = 1;
2598 else if (t_slice > config->cluster_highest_tunnelid)
2599 t_slice = config->cluster_highest_tunnelid;
2600
2601 if (r_slice < 1)
2602 r_slice = 1;
2603 else if (r_slice > (MAXRADIUS - 1))
2604 r_slice = MAXRADIUS - 1;
2605
2606 if (s_slice < 1)
2607 s_slice = 1;
2608 else if (s_slice > config->cluster_highest_sessionid)
2609 s_slice = config->cluster_highest_sessionid;
2610
2611 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2612
2613 for (i = 0; i < t_slice; i++)
2614 {
2615 t++;
2616 if (t > config->cluster_highest_tunnelid)
2617 t = 1;
2618
2619 // check for expired tunnels
2620 if (tunnel[t].die && tunnel[t].die <= TIME)
2621 {
2622 STAT(tunnel_timeout);
2623 tunnelkill(t, "Expired");
2624 t_actions++;
2625 continue;
2626 }
2627 // check for message resend
2628 if (tunnel[t].retry && tunnel[t].controlc)
2629 {
2630 // resend pending messages as timeout on reply
2631 if (tunnel[t].retry <= TIME)
2632 {
2633 controlt *c = tunnel[t].controls;
2634 uint8_t w = tunnel[t].window;
2635 tunnel[t].try++; // another try
2636 if (tunnel[t].try > 5)
2637 tunnelkill(t, "Timeout on control message"); // game over
2638 else
2639 while (c && w--)
2640 {
2641 tunnelsend(c->buf, c->length, t);
2642 c = c->next;
2643 }
2644
2645 t_actions++;
2646 }
2647 }
2648 // Send hello
2649 if (tunnel[t].state == TUNNELOPEN && (time_now - tunnel[t].lastrec) > 60)
2650 {
2651 controlt *c = controlnew(6); // sending HELLO
2652 controladd(c, 0, t); // send the message
2653 LOG(3, 0, t, "Sending HELLO message\n");
2654 t_actions++;
2655 }
2656
2657 // Check for tunnel changes requested from the CLI
2658 if ((a = cli_tunnel_actions[t].action))
2659 {
2660 cli_tunnel_actions[t].action = 0;
2661 if (a & CLI_TUN_KILL)
2662 {
2663 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2664 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2665 t_actions++;
2666 }
2667 }
2668 }
2669
2670 for (i = 0; i < r_slice; i++)
2671 {
2672 r++;
2673 if (r >= MAXRADIUS)
2674 r = 1;
2675
2676 if (!radius[r].state)
2677 continue;
2678
2679 if (radius[r].retry <= TIME)
2680 {
2681 radiusretry(r);
2682 r_actions++;
2683 }
2684 }
2685
2686 for (i = 0; i < s_slice; i++)
2687 {
2688 s++;
2689 if (s > config->cluster_highest_sessionid)
2690 s = 1;
2691
2692 if (!session[s].opened) // Session isn't in use
2693 continue;
2694
2695 // check for expired sessions
2696 if (session[s].die)
2697 {
2698 if (session[s].die <= TIME)
2699 {
2700 sessionkill(s, "Expired");
2701 s_actions++;
2702 }
2703 continue;
2704 }
2705
2706 // PPP timeouts
2707 if (sess_local[s].lcp.restart <= time_now)
2708 {
2709 int next_state = session[s].ppp.lcp;
2710 switch (session[s].ppp.lcp)
2711 {
2712 case RequestSent:
2713 case AckReceived:
2714 next_state = RequestSent;
2715
2716 case AckSent:
2717 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2718 {
2719 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2720 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2721 sess_local[s].lcp.conf_sent++;
2722 sendlcp(s, session[s].tunnel);
2723 change_state(s, lcp, next_state);
2724 }
2725 else
2726 {
2727 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2728 STAT(session_timeout);
2729 }
2730
2731 s_actions++;
2732 }
2733
2734 if (session[s].die)
2735 continue;
2736 }
2737
2738 if (sess_local[s].ipcp.restart <= time_now)
2739 {
2740 int next_state = session[s].ppp.ipcp;
2741 switch (session[s].ppp.ipcp)
2742 {
2743 case RequestSent:
2744 case AckReceived:
2745 next_state = RequestSent;
2746
2747 case AckSent:
2748 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2749 {
2750 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2751 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2752 sess_local[s].ipcp.conf_sent++;
2753 sendipcp(s, session[s].tunnel);
2754 change_state(s, ipcp, next_state);
2755 }
2756 else
2757 {
2758 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2759 STAT(session_timeout);
2760 }
2761
2762 s_actions++;
2763 }
2764
2765 if (session[s].die)
2766 continue;
2767 }
2768
2769 if (sess_local[s].ipv6cp.restart <= time_now)
2770 {
2771 int next_state = session[s].ppp.ipv6cp;
2772 switch (session[s].ppp.ipv6cp)
2773 {
2774 case RequestSent:
2775 case AckReceived:
2776 next_state = RequestSent;
2777
2778 case AckSent:
2779 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2780 {
2781 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2782 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2783 sess_local[s].ipv6cp.conf_sent++;
2784 sendipv6cp(s, session[s].tunnel);
2785 change_state(s, ipv6cp, next_state);
2786 }
2787 else
2788 {
2789 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2790 change_state(s, ipv6cp, Stopped);
2791 }
2792
2793 s_actions++;
2794 }
2795 }
2796
2797 if (sess_local[s].ccp.restart <= time_now)
2798 {
2799 int next_state = session[s].ppp.ccp;
2800 switch (session[s].ppp.ccp)
2801 {
2802 case RequestSent:
2803 case AckReceived:
2804 next_state = RequestSent;
2805
2806 case AckSent:
2807 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2808 {
2809 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2810 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2811 sess_local[s].ccp.conf_sent++;
2812 sendccp(s, session[s].tunnel);
2813 change_state(s, ccp, next_state);
2814 }
2815 else
2816 {
2817 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2818 change_state(s, ccp, Stopped);
2819 }
2820
2821 s_actions++;
2822 }
2823 }
2824
2825 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2826 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2827 {
2828 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2829 STAT(session_timeout);
2830 s_actions++;
2831 continue;
2832 }
2833
2834 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2835 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2836 {
2837 uint8_t b[MAXETHER];
2838
2839 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2840 if (!q) continue;
2841
2842 *q = EchoReq;
2843 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2844 *(uint16_t *)(q + 2) = htons(8); // Length
2845 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2846
2847 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2848 (int)(time_now - session[s].last_packet));
2849 tunnelsend(b, 24, session[s].tunnel); // send it
2850 s_actions++;
2851 }
2852
2853 // Check for actions requested from the CLI
2854 if ((a = cli_session_actions[s].action))
2855 {
2856 int send = 0;
2857
2858 cli_session_actions[s].action = 0;
2859 if (a & CLI_SESS_KILL)
2860 {
2861 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2862 sessionshutdown(s, "Requested by administrator.", 3, 0);
2863 a = 0; // dead, no need to check for other actions
2864 s_actions++;
2865 }
2866
2867 if (a & CLI_SESS_NOSNOOP)
2868 {
2869 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2870 session[s].snoop_ip = 0;
2871 session[s].snoop_port = 0;
2872 s_actions++;
2873 send++;
2874 }
2875 else if (a & CLI_SESS_SNOOP)
2876 {
2877 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2878 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2879 cli_session_actions[s].snoop_port);
2880
2881 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2882 session[s].snoop_port = cli_session_actions[s].snoop_port;
2883 s_actions++;
2884 send++;
2885 }
2886
2887 if (a & CLI_SESS_NOTHROTTLE)
2888 {
2889 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2890 throttle_session(s, 0, 0);
2891 s_actions++;
2892 send++;
2893 }
2894 else if (a & CLI_SESS_THROTTLE)
2895 {
2896 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2897 cli_session_actions[s].throttle_in,
2898 cli_session_actions[s].throttle_out);
2899
2900 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2901 s_actions++;
2902 send++;
2903 }
2904
2905 if (a & CLI_SESS_NOFILTER)
2906 {
2907 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2908 filter_session(s, 0, 0);
2909 s_actions++;
2910 send++;
2911 }
2912 else if (a & CLI_SESS_FILTER)
2913 {
2914 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2915 cli_session_actions[s].filter_in,
2916 cli_session_actions[s].filter_out);
2917
2918 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2919 s_actions++;
2920 send++;
2921 }
2922
2923 if (send)
2924 cluster_send_session(s);
2925 }
2926
2927 // RADIUS interim accounting
2928 if (config->radius_accounting && config->radius_interim > 0
2929 && session[s].ip && !session[s].walled_garden
2930 && !sess_local[s].radius // RADIUS already in progress
2931 && time_now - sess_local[s].last_interim >= config->radius_interim)
2932 {
2933 int rad = radiusnew(s);
2934 if (!rad)
2935 {
2936 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2937 STAT(radius_overflow);
2938 continue;
2939 }
2940
2941 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2942 session[s].user, session[s].unique_id);
2943
2944 radiussend(rad, RADIUSINTERIM);
2945 sess_local[s].last_interim = time_now;
2946 s_actions++;
2947 }
2948 }
2949
2950 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2951 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2952 }
2953
2954 //
2955 // Are we in the middle of a tunnel update, or radius
2956 // requests??
2957 //
2958 static int still_busy(void)
2959 {
2960 int i;
2961 static clockt last_talked = 0;
2962 static clockt start_busy_wait = 0;
2963
2964 if (!config->cluster_iam_master)
2965 {
2966 #ifdef BGP
2967 static time_t stopped_bgp = 0;
2968 if (bgp_configured)
2969 {
2970 if (!stopped_bgp)
2971 {
2972 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2973
2974 for (i = 0; i < BGP_NUM_PEERS; i++)
2975 if (bgp_peers[i].state == Established)
2976 bgp_stop(&bgp_peers[i]);
2977
2978 stopped_bgp = time_now;
2979
2980 // we don't want to become master
2981 cluster_send_ping(0);
2982
2983 return 1;
2984 }
2985
2986 if (time_now < (stopped_bgp + QUIT_DELAY))
2987 return 1;
2988 }
2989 #endif /* BGP */
2990
2991 return 0;
2992 }
2993
2994 if (main_quit == QUIT_SHUTDOWN)
2995 {
2996 static int dropped = 0;
2997 if (!dropped)
2998 {
2999 int i;
3000
3001 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3002 for (i = 1; i < MAXTUNNEL; i++)
3003 if (tunnel[i].ip || tunnel[i].state)
3004 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3005
3006 dropped = 1;
3007 }
3008 }
3009
3010 if (start_busy_wait == 0)
3011 start_busy_wait = TIME;
3012
3013 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3014 {
3015 if (!tunnel[i].controlc)
3016 continue;
3017
3018 if (last_talked != TIME)
3019 {
3020 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3021 last_talked = TIME;
3022 }
3023 return 1;
3024 }
3025
3026 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3027 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3028 {
3029 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3030 return 0;
3031 }
3032
3033 for (i = 1; i < MAXRADIUS; i++)
3034 {
3035 if (radius[i].state == RADIUSNULL)
3036 continue;
3037 if (radius[i].state == RADIUSWAIT)
3038 continue;
3039
3040 if (last_talked != TIME)
3041 {
3042 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3043 last_talked = TIME;
3044 }
3045 return 1;
3046 }
3047
3048 return 0;
3049 }
3050
3051 #ifdef HAVE_EPOLL
3052 # include <sys/epoll.h>
3053 #else
3054 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3055 # include "fake_epoll.h"
3056 #endif
3057
3058 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3059 #define BASE_FDS 6
3060
3061 // additional polled fds
3062 #ifdef BGP
3063 # define EXTRA_FDS BGP_NUM_PEERS
3064 #else
3065 # define EXTRA_FDS 0
3066 #endif
3067
3068 // main loop - gets packets on tun or udp and processes them
3069 static void mainloop(void)
3070 {
3071 int i;
3072 uint8_t buf[65536];
3073 clockt next_cluster_ping = 0; // send initial ping immediately
3074 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3075 int maxevent = sizeof(events)/sizeof(*events);
3076
3077 if ((epollfd = epoll_create(maxevent)) < 0)
3078 {
3079 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3080 exit(1);
3081 }
3082
3083 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3084 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3085
3086 /* setup our fds to poll for input */
3087 {
3088 static struct event_data d[BASE_FDS];
3089 struct epoll_event e;
3090
3091 e.events = EPOLLIN;
3092 i = 0;
3093
3094 d[i].type = FD_TYPE_CLI;
3095 e.data.ptr = &d[i++];
3096 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3097
3098 d[i].type = FD_TYPE_CLUSTER;
3099 e.data.ptr = &d[i++];
3100 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3101
3102 d[i].type = FD_TYPE_TUN;
3103 e.data.ptr = &d[i++];
3104 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3105
3106 d[i].type = FD_TYPE_UDP;
3107 e.data.ptr = &d[i++];
3108 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3109
3110 d[i].type = FD_TYPE_CONTROL;
3111 e.data.ptr = &d[i++];
3112 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3113
3114 d[i].type = FD_TYPE_DAE;
3115 e.data.ptr = &d[i++];
3116 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3117 }
3118
3119 #ifdef BGP
3120 signal(SIGPIPE, SIG_IGN);
3121 bgp_setup(config->as_number);
3122 if (config->bind_address)
3123 bgp_add_route(config->bind_address, 0xffffffff);
3124
3125 for (i = 0; i < BGP_NUM_PEERS; i++)
3126 {
3127 if (config->neighbour[i].name[0])
3128 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3129 config->neighbour[i].as, config->neighbour[i].keepalive,
3130 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3131 }
3132 #endif /* BGP */
3133
3134 while (!main_quit || still_busy())
3135 {
3136 int more = 0;
3137 int n;
3138
3139 if (config->reload_config)
3140 {
3141 // Update the config state based on config settings
3142 update_config();
3143 }
3144
3145 #ifdef BGP
3146 bgp_set_poll();
3147 #endif /* BGP */
3148
3149 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3150 STAT(select_called);
3151
3152 TIME = now(NULL);
3153 if (n < 0)
3154 {
3155 if (errno == EINTR ||
3156 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3157 continue;
3158
3159 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3160 break; // exit
3161 }
3162
3163 if (n)
3164 {
3165 struct sockaddr_in addr;
3166 socklen_t alen;
3167 int c, s;
3168 int udp_ready = 0;
3169 int tun_ready = 0;
3170 int cluster_ready = 0;
3171 int udp_pkts = 0;
3172 int tun_pkts = 0;
3173 int cluster_pkts = 0;
3174 #ifdef BGP
3175 uint32_t bgp_events[BGP_NUM_PEERS];
3176 memset(bgp_events, 0, sizeof(bgp_events));
3177 #endif /* BGP */
3178
3179 for (c = n, i = 0; i < c; i++)
3180 {
3181 struct event_data *d = events[i].data.ptr;
3182 switch (d->type)
3183 {
3184 case FD_TYPE_CLI: // CLI connections
3185 {
3186 int cli;
3187
3188 alen = sizeof(addr);
3189 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3190 {
3191 cli_do(cli);
3192 close(cli);
3193 }
3194 else
3195 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3196
3197 n--;
3198 break;
3199 }
3200
3201 // these are handled below, with multiple interleaved reads
3202 case FD_TYPE_CLUSTER: cluster_ready++; break;
3203 case FD_TYPE_TUN: tun_ready++; break;
3204 case FD_TYPE_UDP: udp_ready++; break;
3205
3206 case FD_TYPE_CONTROL: // nsctl commands
3207 alen = sizeof(addr);
3208 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3209 n--;
3210 break;
3211
3212 case FD_TYPE_DAE: // DAE requests
3213 alen = sizeof(addr);
3214 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3215 n--;
3216 break;
3217
3218 case FD_TYPE_RADIUS: // RADIUS response
3219 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3220 if (s >= 0 && config->cluster_iam_master)
3221 processrad(buf, s, d->index);
3222
3223 n--;
3224 break;
3225
3226 #ifdef BGP
3227 case FD_TYPE_BGP:
3228 bgp_events[d->index] = events[i].events;
3229 n--;
3230 break;
3231 #endif /* BGP */
3232
3233 default:
3234 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3235 }
3236 }
3237
3238 #ifdef BGP
3239 bgp_process(bgp_events);
3240 #endif /* BGP */
3241
3242 for (c = 0; n && c < config->multi_read_count; c++)
3243 {
3244 // L2TP
3245 if (udp_ready)
3246 {
3247 alen = sizeof(addr);
3248 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3249 {
3250 processudp(buf, s, &addr);
3251 udp_pkts++;
3252 }
3253 else
3254 {
3255 udp_ready = 0;
3256 n--;
3257 }
3258 }
3259
3260 // incoming IP
3261 if (tun_ready)
3262 {
3263 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3264 {
3265 processtun(buf, s);
3266 tun_pkts++;
3267 }
3268 else
3269 {
3270 tun_ready = 0;
3271 n--;
3272 }
3273 }
3274
3275 // cluster
3276 if (cluster_ready)
3277 {
3278 alen = sizeof(addr);
3279 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3280 {
3281 processcluster(buf, s, addr.sin_addr.s_addr);
3282 cluster_pkts++;
3283 }
3284 else
3285 {
3286 cluster_ready = 0;
3287 n--;
3288 }
3289 }
3290 }
3291
3292 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3293 STAT(multi_read_used);
3294
3295 if (c >= config->multi_read_count)
3296 {
3297 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3298 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3299
3300 STAT(multi_read_exceeded);
3301 more++;
3302 }
3303 }
3304
3305 // Runs on every machine (master and slaves).
3306 if (next_cluster_ping <= TIME)
3307 {
3308 // Check to see which of the cluster is still alive..
3309
3310 cluster_send_ping(basetime); // Only does anything if we're a slave
3311 cluster_check_master(); // ditto.
3312
3313 cluster_heartbeat(); // Only does anything if we're a master.
3314 cluster_check_slaves(); // ditto.
3315
3316 master_update_counts(); // If we're a slave, send our byte counters to our master.
3317
3318 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3319 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3320 else
3321 next_cluster_ping = TIME + config->cluster_hb_interval;
3322 }
3323
3324 if (!config->cluster_iam_master)
3325 continue;
3326
3327 // Run token bucket filtering queue..
3328 // Only run it every 1/10th of a second.
3329 {
3330 static clockt last_run = 0;
3331 if (last_run != TIME)
3332 {
3333 last_run = TIME;
3334 tbf_run_timer();
3335 }
3336 }
3337
3338 // Handle timeouts, retries etc.
3339 {
3340 static double last_clean = 0;
3341 double this_clean;
3342 double diff;
3343
3344 TIME = now(&this_clean);
3345 diff = this_clean - last_clean;
3346
3347 // Run during idle time (after we've handled
3348 // all incoming packets) or every 1/10th sec
3349 if (!more || diff > 0.1)
3350 {
3351 regular_cleanups(diff);
3352 last_clean = this_clean;
3353 }
3354 }
3355
3356 if (*config->accounting_dir)
3357 {
3358 static clockt next_acct = 0;
3359 static clockt next_shut_acct = 0;
3360
3361 if (next_acct <= TIME)
3362 {
3363 // Dump accounting data
3364 next_acct = TIME + ACCT_TIME;
3365 next_shut_acct = TIME + ACCT_SHUT_TIME;
3366 dump_acct_info(1);
3367 }
3368 else if (next_shut_acct <= TIME)
3369 {
3370 // Dump accounting data for shutdown sessions
3371 next_shut_acct = TIME + ACCT_SHUT_TIME;
3372 if (shut_acct_n)
3373 dump_acct_info(0);
3374 }
3375 }
3376 }
3377
3378 // Are we the master and shutting down??
3379 if (config->cluster_iam_master)
3380 cluster_heartbeat(); // Flush any queued changes..
3381
3382 // Ok. Notify everyone we're shutting down. If we're
3383 // the master, this will force an election.
3384 cluster_send_ping(0);
3385
3386 //
3387 // Important!!! We MUST not process any packets past this point!
3388 LOG(1, 0, 0, "Shutdown complete\n");
3389 }
3390
3391 static void stripdomain(char *host)
3392 {
3393 char *p;
3394
3395 if ((p = strchr(host, '.')))
3396 {
3397 char *domain = 0;
3398 char _domain[1024];
3399
3400 // strip off domain
3401 FILE *resolv = fopen("/etc/resolv.conf", "r");
3402 if (resolv)
3403 {
3404 char buf[1024];
3405 char *b;
3406
3407 while (fgets(buf, sizeof(buf), resolv))
3408 {
3409 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3410 continue;
3411
3412 if (!isspace(buf[6]))
3413 continue;
3414
3415 b = buf + 7;
3416 while (isspace(*b)) b++;
3417
3418 if (*b)
3419 {
3420 char *d = b;
3421 while (*b && !isspace(*b)) b++;
3422 *b = 0;
3423 if (buf[0] == 'd') // domain is canonical
3424 {
3425 domain = d;
3426 break;
3427 }
3428
3429 // first search line
3430 if (!domain)
3431 {
3432 // hold, may be subsequent domain line
3433 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3434 domain = _domain;
3435 }
3436 }
3437 }
3438
3439 fclose(resolv);
3440 }
3441
3442 if (domain)
3443 {
3444 int hl = strlen(host);
3445 int dl = strlen(domain);
3446 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3447 host[hl -dl - 1] = 0;
3448 }
3449 else
3450 {
3451 *p = 0; // everything after first dot
3452 }
3453 }
3454 }
3455
3456 // Init data structures
3457 static void initdata(int optdebug, char *optconfig)
3458 {
3459 int i;
3460
3461 if (!(config = shared_malloc(sizeof(configt))))
3462 {
3463 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3464 exit(1);
3465 }
3466
3467 memset(config, 0, sizeof(configt));
3468 time(&config->start_time);
3469 strncpy(config->config_file, optconfig, strlen(optconfig));
3470 config->debug = optdebug;
3471 config->num_tbfs = MAXTBFS;
3472 config->rl_rate = 28; // 28kbps
3473 config->cluster_mcast_ttl = 1;
3474 config->cluster_master_min_adv = 1;
3475 config->ppp_restart_time = 3;
3476 config->ppp_max_configure = 10;
3477 config->ppp_max_failure = 5;
3478 strcpy(config->random_device, RANDOMDEVICE);
3479
3480 log_stream = stderr;
3481
3482 #ifdef RINGBUFFER
3483 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3484 {
3485 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3486 exit(1);
3487 }
3488 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3489 #endif
3490
3491 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3492 {
3493 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3494 exit(1);
3495 }
3496 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3497 {
3498 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3499 exit(1);
3500 }
3501 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3502 {
3503 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3504 exit(1);
3505 }
3506
3507 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3508 {
3509 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3510 exit(1);
3511 }
3512
3513 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3514 {
3515 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3516 exit(1);
3517 }
3518
3519 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3520 {
3521 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3522 exit(1);
3523 }
3524
3525 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3526 {
3527 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3528 exit(1);
3529 }
3530 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3531
3532 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3533 {
3534 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3535 exit(1);
3536 }
3537 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3538
3539 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3540 {
3541 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3542 exit(1);
3543 }
3544 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3545
3546 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3547 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3548 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3549 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3550
3551 // Put all the sessions on the free list marked as undefined.
3552 for (i = 1; i < MAXSESSION; i++)
3553 {
3554 session[i].next = i + 1;
3555 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3556 }
3557 session[MAXSESSION - 1].next = 0;
3558 sessionfree = 1;
3559
3560 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3561 for (i = 1; i < MAXTUNNEL; i++)
3562 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3563
3564 if (!*hostname)
3565 {
3566 // Grab my hostname unless it's been specified
3567 gethostname(hostname, sizeof(hostname));
3568 stripdomain(hostname);
3569 }
3570
3571 _statistics->start_time = _statistics->last_reset = time(NULL);
3572
3573 #ifdef BGP
3574 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3575 {
3576 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3577 exit(1);
3578 }
3579 #endif /* BGP */
3580 }
3581
3582 static int assign_ip_address(sessionidt s)
3583 {
3584 uint32_t i;
3585 int best = -1;
3586 time_t best_time = time_now;
3587 char *u = session[s].user;
3588 char reuse = 0;
3589
3590
3591 CSTAT(assign_ip_address);
3592
3593 for (i = 1; i < ip_pool_size; i++)
3594 {
3595 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3596 continue;
3597
3598 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3599 {
3600 best = i;
3601 reuse = 1;
3602 break;
3603 }
3604
3605 if (ip_address_pool[i].last < best_time)
3606 {
3607 best = i;
3608 if (!(best_time = ip_address_pool[i].last))
3609 break; // never used, grab this one
3610 }
3611 }
3612
3613 if (best < 0)
3614 {
3615 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3616 return 0;
3617 }
3618
3619 session[s].ip = ip_address_pool[best].address;
3620 session[s].ip_pool_index = best;
3621 ip_address_pool[best].assigned = 1;
3622 ip_address_pool[best].last = time_now;
3623 ip_address_pool[best].session = s;
3624 if (session[s].walled_garden)
3625 /* Don't track addresses of users in walled garden (note: this
3626 means that their address isn't "sticky" even if they get
3627 un-gardened). */
3628 ip_address_pool[best].user[0] = 0;
3629 else
3630 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3631
3632 STAT(ip_allocated);
3633 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3634 reuse ? "Reusing" : "Allocating", best);
3635
3636 return 1;
3637 }
3638
3639 static void free_ip_address(sessionidt s)
3640 {
3641 int i = session[s].ip_pool_index;
3642
3643
3644 CSTAT(free_ip_address);
3645
3646 if (!session[s].ip)
3647 return; // what the?
3648
3649 if (i < 0) // Is this actually part of the ip pool?
3650 i = 0;
3651
3652 STAT(ip_freed);
3653 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3654 session[s].ip = 0;
3655 ip_address_pool[i].assigned = 0;
3656 ip_address_pool[i].session = 0;
3657 ip_address_pool[i].last = time_now;
3658 }
3659
3660 //
3661 // Fsck the address pool against the session table.
3662 // Normally only called when we become a master.
3663 //
3664 // This isn't perfect: We aren't keep tracking of which
3665 // users used to have an IP address.
3666 //
3667 void rebuild_address_pool(void)
3668 {
3669 int i;
3670
3671 //
3672 // Zero the IP pool allocation, and build
3673 // a map from IP address to pool index.
3674 for (i = 1; i < MAXIPPOOL; ++i)
3675 {
3676 ip_address_pool[i].assigned = 0;
3677 ip_address_pool[i].session = 0;
3678 if (!ip_address_pool[i].address)
3679 continue;
3680
3681 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3682 }
3683
3684 for (i = 0; i < MAXSESSION; ++i)
3685 {
3686 int ipid;
3687 if (!(session[i].opened && session[i].ip))
3688 continue;
3689
3690 ipid = - lookup_ipmap(htonl(session[i].ip));
3691
3692 if (session[i].ip_pool_index < 0)
3693 {
3694 // Not allocated out of the pool.
3695 if (ipid < 1) // Not found in the pool either? good.
3696 continue;
3697
3698 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3699 i, fmtaddr(session[i].ip, 0), ipid);
3700
3701 // Fall through and process it as part of the pool.
3702 }
3703
3704
3705 if (ipid > MAXIPPOOL || ipid < 0)
3706 {
3707 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3708 ipid = -1;
3709 session[i].ip_pool_index = ipid;
3710 continue;
3711 }
3712
3713 ip_address_pool[ipid].assigned = 1;
3714 ip_address_pool[ipid].session = i;
3715 ip_address_pool[ipid].last = time_now;
3716 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3717 session[i].ip_pool_index = ipid;
3718 cache_ipmap(session[i].ip, i); // Fix the ip map.
3719 }
3720 }
3721
3722 //
3723 // Fix the address pool to match a changed session.
3724 // (usually when the master sends us an update).
3725 static void fix_address_pool(int sid)
3726 {
3727 int ipid;
3728
3729 ipid = session[sid].ip_pool_index;
3730
3731 if (ipid > ip_pool_size)
3732 return; // Ignore it. rebuild_address_pool will fix it up.
3733
3734 if (ip_address_pool[ipid].address != session[sid].ip)
3735 return; // Just ignore it. rebuild_address_pool will take care of it.
3736
3737 ip_address_pool[ipid].assigned = 1;
3738 ip_address_pool[ipid].session = sid;
3739 ip_address_pool[ipid].last = time_now;
3740 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3741 }
3742
3743 //
3744 // Add a block of addresses to the IP pool to hand out.
3745 //
3746 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3747 {
3748 int i;
3749 if (mask == 0)
3750 mask = 0xffffffff; // Host route only.
3751
3752 addr &= mask;
3753
3754 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3755 return ;
3756
3757 for (i = addr ;(i & mask) == addr; ++i)
3758 {
3759 if ((i & 0xff) == 0 || (i&0xff) == 255)
3760 continue; // Skip 0 and broadcast addresses.
3761
3762 ip_address_pool[ip_pool_size].address = i;
3763 ip_address_pool[ip_pool_size].assigned = 0;
3764 ++ip_pool_size;
3765 if (ip_pool_size >= MAXIPPOOL)
3766 {
3767 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3768 return;
3769 }
3770 }
3771 }
3772
3773 // Initialize the IP address pool
3774 static void initippool()
3775 {
3776 FILE *f;
3777 char *p;
3778 char buf[4096];
3779 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3780
3781 if (!(f = fopen(IPPOOLFILE, "r")))
3782 {
3783 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3784 exit(1);
3785 }
3786
3787 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3788 {
3789 char *pool = buf;
3790 buf[4095] = 0; // Force it to be zero terminated/
3791
3792 if (*buf == '#' || *buf == '\n')
3793 continue; // Skip comments / blank lines
3794 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3795 if ((p = (char *)strchr(buf, ':')))
3796 {
3797 in_addr_t src;
3798 *p = '\0';
3799 src = inet_addr(buf);
3800 if (src == INADDR_NONE)
3801 {
3802 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3803 exit(1);
3804 }
3805 // This entry is for a specific IP only
3806 if (src != config->bind_address)
3807 continue;
3808 *p = ':';
3809 pool = p+1;
3810 }
3811 if ((p = (char *)strchr(pool, '/')))
3812 {
3813 // It's a range
3814 int numbits = 0;
3815 in_addr_t start = 0, mask = 0;
3816
3817 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3818 *p++ = 0;
3819 if (!*p || !(numbits = atoi(p)))
3820 {
3821 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3822 continue;
3823 }
3824 start = ntohl(inet_addr(pool));
3825 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3826
3827 // Add a static route for this pool
3828 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3829 fmtaddr(htonl(start), 0), 32 + mask);
3830
3831 routeset(0, start, mask, 0, 1);
3832
3833 add_to_ip_pool(start, mask);
3834 }
3835 else
3836 {
3837 // It's a single ip address
3838 add_to_ip_pool(inet_addr(pool), 0);
3839 }
3840 }
3841 fclose(f);
3842 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3843 }
3844
3845 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3846 {
3847 struct sockaddr_in snoop_addr = {0};
3848 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3849 return;
3850
3851 snoop_addr.sin_family = AF_INET;
3852 snoop_addr.sin_addr.s_addr = destination;
3853 snoop_addr.sin_port = ntohs(port);
3854
3855 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3856 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3857 htons(snoop_addr.sin_port));
3858
3859 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3860 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3861
3862 STAT(packets_snooped);
3863 }
3864
3865 static int dump_session(FILE **f, sessiont *s)
3866 {
3867 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3868 return 1;
3869
3870 if (!*f)
3871 {
3872 char filename[1024];
3873 char timestr[64];
3874 time_t now = time(NULL);
3875
3876 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3877 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3878
3879 if (!(*f = fopen(filename, "w")))
3880 {
3881 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3882 return 0;
3883 }
3884
3885 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3886 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3887 "# host: %s\n"
3888 "# endpoint: %s\n"
3889 "# time: %ld\n"
3890 "# uptime: %ld\n"
3891 "# format: username ip qos uptxoctets downrxoctets\n",
3892 hostname,
3893 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3894 now,
3895 now - basetime);
3896 }
3897
3898 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3899 fprintf(*f, "%s %s %d %u %u\n",
3900 s->user, // username
3901 fmtaddr(htonl(s->ip), 0), // ip
3902 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3903 (uint32_t) s->cin_delta, // uptxoctets
3904 (uint32_t) s->cout_delta); // downrxoctets
3905
3906 s->cin_delta = s->cout_delta = 0;
3907
3908 return 1;
3909 }
3910
3911 static void dump_acct_info(int all)
3912 {
3913 int i;
3914 FILE *f = NULL;
3915
3916
3917 CSTAT(dump_acct_info);
3918
3919 if (shut_acct_n)
3920 {
3921 for (i = 0; i < shut_acct_n; i++)
3922 dump_session(&f, &shut_acct[i]);
3923
3924 shut_acct_n = 0;
3925 }
3926
3927 if (all)
3928 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3929 dump_session(&f, &session[i]);
3930
3931 if (f)
3932 fclose(f);
3933 }
3934
3935 // Main program
3936 int main(int argc, char *argv[])
3937 {
3938 int i;
3939 int optdebug = 0;
3940 char *optconfig = CONFIGFILE;
3941
3942 time(&basetime); // start clock
3943
3944 // scan args
3945 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3946 {
3947 switch (i)
3948 {
3949 case 'd':
3950 if (fork()) exit(0);
3951 setsid();
3952 freopen("/dev/null", "r", stdin);
3953 freopen("/dev/null", "w", stdout);
3954 freopen("/dev/null", "w", stderr);
3955 break;
3956 case 'v':
3957 optdebug++;
3958 break;
3959 case 'c':
3960 optconfig = optarg;
3961 break;
3962 case 'h':
3963 snprintf(hostname, sizeof(hostname), "%s", optarg);
3964 break;
3965 default:
3966 printf("Args are:\n"
3967 "\t-d\t\tDetach from terminal\n"
3968 "\t-c <file>\tConfig file\n"
3969 "\t-h <hostname>\tForce hostname\n"
3970 "\t-v\t\tDebug\n");
3971
3972 return (0);
3973 break;
3974 }
3975 }
3976
3977 // Start the timer routine off
3978 time(&time_now);
3979 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3980 signal(SIGALRM, sigalrm_handler);
3981 siginterrupt(SIGALRM, 0);
3982
3983 initplugins();
3984 initdata(optdebug, optconfig);
3985
3986 init_cli(hostname);
3987 read_config_file();
3988 init_tbf(config->num_tbfs);
3989
3990 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3991 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3992 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3993 {
3994 struct rlimit rlim;
3995 rlim.rlim_cur = RLIM_INFINITY;
3996 rlim.rlim_max = RLIM_INFINITY;
3997 // Remove the maximum core size
3998 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3999 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4000
4001 // Make core dumps go to /tmp
4002 chdir("/tmp");
4003 }
4004
4005 if (config->scheduler_fifo)
4006 {
4007 int ret;
4008 struct sched_param params = {0};
4009 params.sched_priority = 1;
4010
4011 if (get_nprocs() < 2)
4012 {
4013 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4014 config->scheduler_fifo = 0;
4015 }
4016 else
4017 {
4018 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4019 {
4020 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4021 }
4022 else
4023 {
4024 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4025 config->scheduler_fifo = 0;
4026 }
4027 }
4028 }
4029
4030 /* Set up the cluster communications port. */
4031 if (cluster_init() < 0)
4032 exit(1);
4033
4034 inittun();
4035 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4036
4037 initudp();
4038 initrad();
4039 initippool();
4040
4041 // seed prng
4042 {
4043 unsigned seed = time_now ^ getpid();
4044 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4045 srand(seed);
4046 }
4047
4048 signal(SIGHUP, sighup_handler);
4049 signal(SIGCHLD, sigchild_handler);
4050 signal(SIGTERM, shutdown_handler);
4051 signal(SIGINT, shutdown_handler);
4052 signal(SIGQUIT, shutdown_handler);
4053
4054 // Prevent us from getting paged out
4055 if (config->lock_pages)
4056 {
4057 if (!mlockall(MCL_CURRENT))
4058 LOG(1, 0, 0, "Locking pages into memory\n");
4059 else
4060 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4061 }
4062
4063 alarm(1);
4064
4065 // Drop privileges here
4066 if (config->target_uid > 0 && geteuid() == 0)
4067 setuid(config->target_uid);
4068
4069 mainloop();
4070
4071 /* remove plugins (so cleanup code gets run) */
4072 plugins_done();
4073
4074 // Remove the PID file if we wrote it
4075 if (config->wrote_pid && *config->pid_file == '/')
4076 unlink(config->pid_file);
4077
4078 /* kill CLI children */
4079 signal(SIGTERM, SIG_IGN);
4080 kill(0, SIGTERM);
4081 return 0;
4082 }
4083
4084 static void sighup_handler(int sig)
4085 {
4086 if (log_stream)
4087 {
4088 if (log_stream != stderr)
4089 fclose(log_stream);
4090
4091 log_stream = NULL;
4092 }
4093
4094 read_config_file();
4095 }
4096
4097 static void sigalrm_handler(int sig)
4098 {
4099 // Log current traffic stats
4100
4101 snprintf(config->bandwidth, sizeof(config->bandwidth),
4102 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4103 (udp_rx / 1024.0 / 1024.0 * 8),
4104 (eth_tx / 1024.0 / 1024.0 * 8),
4105 (eth_rx / 1024.0 / 1024.0 * 8),
4106 (udp_tx / 1024.0 / 1024.0 * 8),
4107 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4108 udp_rx_pkt, eth_rx_pkt);
4109
4110 udp_tx = udp_rx = 0;
4111 udp_rx_pkt = eth_rx_pkt = 0;
4112 eth_tx = eth_rx = 0;
4113
4114 if (config->dump_speed)
4115 printf("%s\n", config->bandwidth);
4116
4117 // Update the internal time counter
4118 time(&time_now);
4119 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4120 alarm(1);
4121
4122 {
4123 // Run timer hooks
4124 struct param_timer p = { time_now };
4125 run_plugins(PLUGIN_TIMER, &p);
4126 }
4127
4128 }
4129
4130 static void shutdown_handler(int sig)
4131 {
4132 LOG(1, 0, 0, "Shutting down\n");
4133 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4134 }
4135
4136 static void sigchild_handler(int sig)
4137 {
4138 while (waitpid(-1, NULL, WNOHANG) > 0)
4139 ;
4140 }
4141
4142 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4143 {
4144 MD5_CTX ctx;
4145 *challenge_response = NULL;
4146
4147 if (!*config->l2tpsecret)
4148 {
4149 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4150 return;
4151 }
4152
4153 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4154
4155 *challenge_response = calloc(17, 1);
4156
4157 MD5_Init(&ctx);
4158 MD5_Update(&ctx, &id, 1);
4159 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4160 MD5_Update(&ctx, challenge, challenge_length);
4161 MD5_Final(*challenge_response, &ctx);
4162
4163 return;
4164 }
4165
4166 static int facility_value(char *name)
4167 {
4168 int i;
4169 for (i = 0; facilitynames[i].c_name; i++)
4170 {
4171 if (strcmp(facilitynames[i].c_name, name) == 0)
4172 return facilitynames[i].c_val;
4173 }
4174 return 0;
4175 }
4176
4177 static void update_config()
4178 {
4179 int i;
4180 char *p;
4181 static int timeout = 0;
4182 static int interval = 0;
4183
4184 // Update logging
4185 closelog();
4186 syslog_log = 0;
4187 if (log_stream)
4188 {
4189 if (log_stream != stderr)
4190 fclose(log_stream);
4191
4192 log_stream = NULL;
4193 }
4194
4195 if (*config->log_filename)
4196 {
4197 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4198 {
4199 char *p = config->log_filename + 7;
4200 if (*p)
4201 {
4202 openlog("l2tpns", LOG_PID, facility_value(p));
4203 syslog_log = 1;
4204 }
4205 }
4206 else if (strchr(config->log_filename, '/') == config->log_filename)
4207 {
4208 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4209 {
4210 fseek(log_stream, 0, SEEK_END);
4211 setbuf(log_stream, NULL);
4212 }
4213 else
4214 {
4215 log_stream = stderr;
4216 setbuf(log_stream, NULL);
4217 }
4218 }
4219 }
4220 else
4221 {
4222 log_stream = stderr;
4223 setbuf(log_stream, NULL);
4224 }
4225
4226 // Update radius
4227 config->numradiusservers = 0;
4228 for (i = 0; i < MAXRADSERVER; i++)
4229 if (config->radiusserver[i])
4230 {
4231 config->numradiusservers++;
4232 // Set radius port: if not set, take the port from the
4233 // first radius server. For the first radius server,
4234 // take the #defined default value from l2tpns.h
4235
4236 // test twice, In case someone works with
4237 // a secondary radius server without defining
4238 // a primary one, this will work even then.
4239 if (i > 0 && !config->radiusport[i])
4240 config->radiusport[i] = config->radiusport[i-1];
4241 if (!config->radiusport[i])
4242 config->radiusport[i] = RADPORT;
4243 }
4244
4245 if (!config->numradiusservers)
4246 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4247
4248 // parse radius_authtypes_s
4249 config->radius_authtypes = config->radius_authprefer = 0;
4250 p = config->radius_authtypes_s;
4251 while (p && *p)
4252 {
4253 char *s = strpbrk(p, " \t,");
4254 int type = 0;
4255
4256 if (s)
4257 {
4258 *s++ = 0;
4259 while (*s == ' ' || *s == '\t')
4260 s++;
4261
4262 if (!*s)
4263 s = 0;
4264 }
4265
4266 if (!strncasecmp("chap", p, strlen(p)))
4267 type = AUTHCHAP;
4268 else if (!strncasecmp("pap", p, strlen(p)))
4269 type = AUTHPAP;
4270 else
4271 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4272
4273 config->radius_authtypes |= type;
4274 if (!config->radius_authprefer)
4275 config->radius_authprefer = type;
4276
4277 p = s;
4278 }
4279
4280 if (!config->radius_authtypes)
4281 {
4282 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4283 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4284 }
4285
4286 // normalise radius_authtypes_s
4287 if (config->radius_authprefer == AUTHPAP)
4288 {
4289 strcpy(config->radius_authtypes_s, "pap");
4290 if (config->radius_authtypes & AUTHCHAP)
4291 strcat(config->radius_authtypes_s, ", chap");
4292 }
4293 else
4294 {
4295 strcpy(config->radius_authtypes_s, "chap");
4296 if (config->radius_authtypes & AUTHPAP)
4297 strcat(config->radius_authtypes_s, ", pap");
4298 }
4299
4300 if (!config->radius_dae_port)
4301 config->radius_dae_port = DAEPORT;
4302
4303 // re-initialise the random number source
4304 initrandom(config->random_device);
4305
4306 // Update plugins
4307 for (i = 0; i < MAXPLUGINS; i++)
4308 {
4309 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4310 continue;
4311
4312 if (*config->plugins[i])
4313 {
4314 // Plugin added
4315 add_plugin(config->plugins[i]);
4316 }
4317 else if (*config->old_plugins[i])
4318 {
4319 // Plugin removed
4320 remove_plugin(config->old_plugins[i]);
4321 }
4322 }
4323
4324 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4325 if (!config->multi_read_count) config->multi_read_count = 10;
4326 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4327 if (!*config->cluster_interface)
4328 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4329
4330 if (!config->cluster_hb_interval)
4331 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4332
4333 if (!config->cluster_hb_timeout)
4334 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4335
4336 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4337 {
4338 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4339 // late, ensure we're sufficiently larger than that
4340 int t = 4 * config->cluster_hb_interval + 11;
4341
4342 if (config->cluster_hb_timeout < t)
4343 {
4344 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4345 config->cluster_hb_timeout = t;
4346 }
4347
4348 // Push timing changes to the slaves immediately if we're the master
4349 if (config->cluster_iam_master)
4350 cluster_heartbeat();
4351
4352 interval = config->cluster_hb_interval;
4353 timeout = config->cluster_hb_timeout;
4354 }
4355
4356 // Write PID file
4357 if (*config->pid_file == '/' && !config->wrote_pid)
4358 {
4359 FILE *f;
4360 if ((f = fopen(config->pid_file, "w")))
4361 {
4362 fprintf(f, "%d\n", getpid());
4363 fclose(f);
4364 config->wrote_pid = 1;
4365 }
4366 else
4367 {
4368 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4369 }
4370 }
4371
4372 config->reload_config = 0;
4373 }
4374
4375 static void read_config_file()
4376 {
4377 FILE *f;
4378
4379 if (!config->config_file) return;
4380 if (!(f = fopen(config->config_file, "r")))
4381 {
4382 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4383 return;
4384 }
4385
4386 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4387 cli_do_file(f);
4388 LOG(3, 0, 0, "Done reading config file\n");
4389 fclose(f);
4390 update_config();
4391 }
4392
4393 int sessionsetup(sessionidt s, tunnelidt t)
4394 {
4395 // A session now exists, set it up
4396 in_addr_t ip;
4397 char *user;
4398 sessionidt i;
4399 int r;
4400
4401 CSTAT(sessionsetup);
4402
4403 LOG(3, s, t, "Doing session setup for session\n");
4404
4405 if (!session[s].ip)
4406 {
4407 assign_ip_address(s);
4408 if (!session[s].ip)
4409 {
4410 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4411 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4412 return 0;
4413 }
4414 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4415 fmtaddr(htonl(session[s].ip), 0));
4416 }
4417
4418
4419 // Make sure this is right
4420 session[s].tunnel = t;
4421
4422 // zap old sessions with same IP and/or username
4423 // Don't kill gardened sessions - doing so leads to a DoS
4424 // from someone who doesn't need to know the password
4425 {
4426 ip = session[s].ip;
4427 user = session[s].user;
4428 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4429 {
4430 if (i == s) continue;
4431 if (!session[s].opened) continue;
4432 if (ip == session[i].ip)
4433 {
4434 sessionkill(i, "Duplicate IP address");
4435 continue;
4436 }
4437
4438 if (config->allow_duplicate_users) continue;
4439 if (session[s].walled_garden || session[i].walled_garden) continue;
4440 if (!strcasecmp(user, session[i].user))
4441 sessionkill(i, "Duplicate session for users");
4442 }
4443 }
4444
4445 {
4446 int routed = 0;
4447
4448 // Add the route for this session.
4449 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4450 {
4451 if ((session[s].ip & session[s].route[r].mask) ==
4452 (session[s].route[r].ip & session[s].route[r].mask))
4453 routed++;
4454
4455 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4456 }
4457
4458 // Static IPs need to be routed if not already
4459 // convered by a Framed-Route. Anything else is part
4460 // of the IP address pool and is already routed, it
4461 // just needs to be added to the IP cache.
4462 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4463 if (session[s].ip_pool_index == -1) // static ip
4464 {
4465 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4466 }
4467 else
4468 cache_ipmap(session[s].ip, s);
4469 }
4470
4471 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4472 lcp_open(s, t); // transition to Network phase and send initial IPCP
4473
4474 // Run the plugin's against this new session.
4475 {
4476 struct param_new_session data = { &tunnel[t], &session[s] };
4477 run_plugins(PLUGIN_NEW_SESSION, &data);
4478 }
4479
4480 // Allocate TBFs if throttled
4481 if (session[s].throttle_in || session[s].throttle_out)
4482 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4483
4484 session[s].last_packet = time_now;
4485
4486 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4487 fmtaddr(htonl(session[s].ip), 0),
4488 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4489
4490 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4491
4492 return 1; // RADIUS OK and IP allocated, done...
4493 }
4494
4495 //
4496 // This session just got dropped on us by the master or something.
4497 // Make sure our tables up up to date...
4498 //
4499 int load_session(sessionidt s, sessiont *new)
4500 {
4501 int i;
4502 int newip = 0;
4503
4504 // Sanity checks.
4505 if (new->ip_pool_index >= MAXIPPOOL ||
4506 new->tunnel >= MAXTUNNEL)
4507 {
4508 LOG(0, s, 0, "Strange session update received!\n");
4509 // FIXME! What to do here?
4510 return 0;
4511 }
4512
4513 //
4514 // Ok. All sanity checks passed. Now we're committed to
4515 // loading the new session.
4516 //
4517
4518 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4519
4520 // See if routes/ip cache need updating
4521 if (new->ip != session[s].ip)
4522 newip++;
4523
4524 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4525 if (new->route[i].ip != session[s].route[i].ip ||
4526 new->route[i].mask != session[s].route[i].mask)
4527 newip++;
4528
4529 // needs update
4530 if (newip)
4531 {
4532 int routed = 0;
4533
4534 // remove old routes...
4535 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4536 {
4537 if ((session[s].ip & session[s].route[i].mask) ==
4538 (session[s].route[i].ip & session[s].route[i].mask))
4539 routed++;
4540
4541 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4542 }
4543
4544 // ...ip
4545 if (session[s].ip)
4546 {
4547 if (session[s].ip_pool_index == -1) // static IP
4548 {
4549 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4550 }
4551 else // It's part of the IP pool, remove it manually.
4552 uncache_ipmap(session[s].ip);
4553 }
4554
4555 routed = 0;
4556
4557 // add new routes...
4558 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4559 {
4560 if ((new->ip & new->route[i].mask) ==
4561 (new->route[i].ip & new->route[i].mask))
4562 routed++;
4563
4564 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4565 }
4566
4567 // ...ip
4568 if (new->ip)
4569 {
4570 // If there's a new one, add it.
4571 if (new->ip_pool_index == -1)
4572 {
4573 if (!routed) routeset(s, new->ip, 0, 0, 1);
4574 }
4575 else
4576 cache_ipmap(new->ip, s);
4577 }
4578 }
4579
4580 // check v6 routing
4581 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4582 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4583
4584 // check filters
4585 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4586 {
4587 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4588 new->filter_in = 0;
4589 }
4590
4591 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4592 {
4593 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4594 new->filter_out = 0;
4595 }
4596
4597 if (new->filter_in != session[s].filter_in)
4598 {
4599 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4600 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4601 }
4602
4603 if (new->filter_out != session[s].filter_out)
4604 {
4605 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4606 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4607 }
4608
4609 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4610 // for walking the sessions to forward byte counts to the master.
4611 config->cluster_highest_sessionid = s;
4612
4613 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4614
4615 // Do fixups into address pool.
4616 if (new->ip_pool_index != -1)
4617 fix_address_pool(s);
4618
4619 return 1;
4620 }
4621
4622 static void initplugins()
4623 {
4624 int i;
4625
4626 loaded_plugins = ll_init();
4627 // Initialize the plugins to nothing
4628 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4629 plugins[i] = ll_init();
4630 }
4631
4632 static void *open_plugin(char *plugin_name, int load)
4633 {
4634 char path[256] = "";
4635
4636 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4637 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4638 return dlopen(path, RTLD_NOW);
4639 }
4640
4641 // plugin callback to get a config value
4642 static void *getconfig(char *key, enum config_typet type)
4643 {
4644 int i;
4645
4646 for (i = 0; config_values[i].key; i++)
4647 {
4648 if (!strcmp(config_values[i].key, key))
4649 {
4650 if (config_values[i].type == type)
4651 return ((void *) config) + config_values[i].offset;
4652
4653 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4654 key, type, config_values[i].type);
4655
4656 return 0;
4657 }
4658 }
4659
4660 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4661 return 0;
4662 }
4663
4664 static int add_plugin(char *plugin_name)
4665 {
4666 static struct pluginfuncs funcs = {
4667 _log,
4668 _log_hex,
4669 fmtaddr,
4670 sessionbyuser,
4671 sessiontbysessionidt,
4672 sessionidtbysessiont,
4673 radiusnew,
4674 radiussend,
4675 getconfig,
4676 sessionshutdown,
4677 sessionkill,
4678 throttle_session,
4679 cluster_send_session,
4680 };
4681
4682 void *p = open_plugin(plugin_name, 1);
4683 int (*initfunc)(struct pluginfuncs *);
4684 int i;
4685
4686 if (!p)
4687 {
4688 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4689 return -1;
4690 }
4691
4692 if (ll_contains(loaded_plugins, p))
4693 {
4694 dlclose(p);
4695 return 0; // already loaded
4696 }
4697
4698 {
4699 int *v = dlsym(p, "plugin_api_version");
4700 if (!v || *v != PLUGIN_API_VERSION)
4701 {
4702 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4703 dlclose(p);
4704 return -1;
4705 }
4706 }
4707
4708 if ((initfunc = dlsym(p, "plugin_init")))
4709 {
4710 if (!initfunc(&funcs))
4711 {
4712 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4713 dlclose(p);
4714 return -1;
4715 }
4716 }
4717
4718 ll_push(loaded_plugins, p);
4719
4720 for (i = 0; i < max_plugin_functions; i++)
4721 {
4722 void *x;
4723 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4724 {
4725 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4726 ll_push(plugins[i], x);
4727 }
4728 }
4729
4730 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4731 return 1;
4732 }
4733
4734 static void run_plugin_done(void *plugin)
4735 {
4736 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4737
4738 if (donefunc)
4739 donefunc();
4740 }
4741
4742 static int remove_plugin(char *plugin_name)
4743 {
4744 void *p = open_plugin(plugin_name, 0);
4745 int loaded = 0;
4746
4747 if (!p)
4748 return -1;
4749
4750 if (ll_contains(loaded_plugins, p))
4751 {
4752 int i;
4753 for (i = 0; i < max_plugin_functions; i++)
4754 {
4755 void *x;
4756 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4757 ll_delete(plugins[i], x);
4758 }
4759
4760 ll_delete(loaded_plugins, p);
4761 run_plugin_done(p);
4762 loaded = 1;
4763 }
4764
4765 dlclose(p);
4766 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4767 return loaded;
4768 }
4769
4770 int run_plugins(int plugin_type, void *data)
4771 {
4772 int (*func)(void *data);
4773
4774 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4775 return PLUGIN_RET_ERROR;
4776
4777 ll_reset(plugins[plugin_type]);
4778 while ((func = ll_next(plugins[plugin_type])))
4779 {
4780 int r = func(data);
4781
4782 if (r != PLUGIN_RET_OK)
4783 return r; // stop here
4784 }
4785
4786 return PLUGIN_RET_OK;
4787 }
4788
4789 static void plugins_done()
4790 {
4791 void *p;
4792
4793 ll_reset(loaded_plugins);
4794 while ((p = ll_next(loaded_plugins)))
4795 run_plugin_done(p);
4796 }
4797
4798 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4799 {
4800 struct nsctl request;
4801 struct nsctl response;
4802 int type = unpack_control(&request, buf, len);
4803 int r;
4804 void *p;
4805
4806 if (log_stream && config->debug >= 4)
4807 {
4808 if (type < 0)
4809 {
4810 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4811 fmtaddr(addr->sin_addr.s_addr, 0), type);
4812 }
4813 else
4814 {
4815 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4816 dump_control(&request, log_stream);
4817 }
4818 }
4819
4820 switch (type)
4821 {
4822 case NSCTL_REQ_LOAD:
4823 if (request.argc != 1)
4824 {
4825 response.type = NSCTL_RES_ERR;
4826 response.argc = 1;
4827 response.argv[0] = "name of plugin required";
4828 }
4829 else if ((r = add_plugin(request.argv[0])) < 1)
4830 {
4831 response.type = NSCTL_RES_ERR;
4832 response.argc = 1;
4833 response.argv[0] = !r
4834 ? "plugin already loaded"
4835 : "error loading plugin";
4836 }
4837 else
4838 {
4839 response.type = NSCTL_RES_OK;
4840 response.argc = 0;
4841 }
4842
4843 break;
4844
4845 case NSCTL_REQ_UNLOAD:
4846 if (request.argc != 1)
4847 {
4848 response.type = NSCTL_RES_ERR;
4849 response.argc = 1;
4850 response.argv[0] = "name of plugin required";
4851 }
4852 else if ((r = remove_plugin(request.argv[0])) < 1)
4853 {
4854 response.type = NSCTL_RES_ERR;
4855 response.argc = 1;
4856 response.argv[0] = !r
4857 ? "plugin not loaded"
4858 : "plugin not found";
4859 }
4860 else
4861 {
4862 response.type = NSCTL_RES_OK;
4863 response.argc = 0;
4864 }
4865
4866 break;
4867
4868 case NSCTL_REQ_HELP:
4869 response.type = NSCTL_RES_OK;
4870 response.argc = 0;
4871
4872 ll_reset(loaded_plugins);
4873 while ((p = ll_next(loaded_plugins)))
4874 {
4875 char **help = dlsym(p, "plugin_control_help");
4876 while (response.argc < 0xff && help && *help)
4877 response.argv[response.argc++] = *help++;
4878 }
4879
4880 break;
4881
4882 case NSCTL_REQ_CONTROL:
4883 {
4884 struct param_control param = {
4885 config->cluster_iam_master,
4886 request.argc,
4887 request.argv,
4888 0,
4889 NULL,
4890 };
4891
4892 int r = run_plugins(PLUGIN_CONTROL, &param);
4893
4894 if (r == PLUGIN_RET_ERROR)
4895 {
4896 response.type = NSCTL_RES_ERR;
4897 response.argc = 1;
4898 response.argv[0] = param.additional
4899 ? param.additional
4900 : "error returned by plugin";
4901 }
4902 else if (r == PLUGIN_RET_NOTMASTER)
4903 {
4904 static char msg[] = "must be run on master: 000.000.000.000";
4905
4906 response.type = NSCTL_RES_ERR;
4907 response.argc = 1;
4908 if (config->cluster_master_address)
4909 {
4910 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4911 response.argv[0] = msg;
4912 }
4913 else
4914 {
4915 response.argv[0] = "must be run on master: none elected";
4916 }
4917 }
4918 else if (!(param.response & NSCTL_RESPONSE))
4919 {
4920 response.type = NSCTL_RES_ERR;
4921 response.argc = 1;
4922 response.argv[0] = param.response
4923 ? "unrecognised response value from plugin"
4924 : "unhandled action";
4925 }
4926 else
4927 {
4928 response.type = param.response;
4929 response.argc = 0;
4930 if (param.additional)
4931 {
4932 response.argc = 1;
4933 response.argv[0] = param.additional;
4934 }
4935 }
4936 }
4937
4938 break;
4939
4940 default:
4941 response.type = NSCTL_RES_ERR;
4942 response.argc = 1;
4943 response.argv[0] = "error unpacking control packet";
4944 }
4945
4946 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4947 if (!buf)
4948 {
4949 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4950 return;
4951 }
4952
4953 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4954 if (r > 0)
4955 {
4956 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4957 if (log_stream && config->debug >= 4)
4958 {
4959 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4960 dump_control(&response, log_stream);
4961 }
4962 }
4963 else
4964 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4965 fmtaddr(addr->sin_addr.s_addr, 0), r);
4966
4967 free(buf);
4968 }
4969
4970 static tunnelidt new_tunnel()
4971 {
4972 tunnelidt i;
4973 for (i = 1; i < MAXTUNNEL; i++)
4974 {
4975 if (tunnel[i].state == TUNNELFREE)
4976 {
4977 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4978 if (i > config->cluster_highest_tunnelid)
4979 config->cluster_highest_tunnelid = i;
4980 return i;
4981 }
4982 }
4983 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4984 return 0;
4985 }
4986
4987 //
4988 // We're becoming the master. Do any required setup..
4989 //
4990 // This is principally telling all the plugins that we're
4991 // now a master, and telling them about all the sessions
4992 // that are active too..
4993 //
4994 void become_master(void)
4995 {
4996 int s, i;
4997 static struct event_data d[RADIUS_FDS];
4998 struct epoll_event e;
4999
5000 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5001
5002 // running a bunch of iptables commands is slow and can cause
5003 // the master to drop tunnels on takeover--kludge around the
5004 // problem by forking for the moment (note: race)
5005 if (!fork_and_close())
5006 {
5007 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5008 {
5009 if (!session[s].opened) // Not an in-use session.
5010 continue;
5011
5012 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5013 }
5014 exit(0);
5015 }
5016
5017 // add radius fds
5018 e.events = EPOLLIN;
5019 for (i = 0; i < RADIUS_FDS; i++)
5020 {
5021 d[i].type = FD_TYPE_RADIUS;
5022 d[i].index = i;
5023 e.data.ptr = &d[i];
5024
5025 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5026 }
5027 }
5028
5029 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5030 {
5031 int s, i;
5032 int count = 0;
5033 int buckets[64];
5034
5035 if (CLI_HELP_REQUESTED)
5036 return CLI_HELP_NO_ARGS;
5037
5038 time(&time_now);
5039 for (i = 0; i < 64;++i) buckets[i] = 0;
5040
5041 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5042 {
5043 int idle;
5044 if (!session[s].opened)
5045 continue;
5046
5047 idle = time_now - session[s].last_packet;
5048 idle /= 5 ; // In multiples of 5 seconds.
5049 if (idle < 0)
5050 idle = 0;
5051 if (idle > 63)
5052 idle = 63;
5053
5054 ++count;
5055 ++buckets[idle];
5056 }
5057
5058 for (i = 0; i < 63; ++i)
5059 {
5060 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5061 }
5062 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5063 cli_print(cli, "%d total sessions open.", count);
5064 return CLI_OK;
5065 }
5066
5067 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5068 {
5069 int s, i;
5070 int count = 0;
5071 int buckets[64];
5072
5073 if (CLI_HELP_REQUESTED)
5074 return CLI_HELP_NO_ARGS;
5075
5076 time(&time_now);
5077 for (i = 0; i < 64;++i) buckets[i] = 0;
5078
5079 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5080 {
5081 int open = 0, d;
5082 if (!session[s].opened)
5083 continue;
5084
5085 d = time_now - session[s].opened;
5086 if (d < 0)
5087 d = 0;
5088 while (d > 1 && open < 32)
5089 {
5090 ++open;
5091 d >>= 1; // half.
5092 }
5093 ++count;
5094 ++buckets[open];
5095 }
5096
5097 s = 1;
5098 for (i = 0; i < 30; ++i)
5099 {
5100 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5101 s <<= 1;
5102 }
5103 cli_print(cli, "%d total sessions open.", count);
5104 return CLI_OK;
5105 }
5106
5107 /* Unhide an avp.
5108 *
5109 * This unencodes the AVP using the L2TP secret and the previously
5110 * stored random vector. It overwrites the hidden data with the
5111 * unhidden AVP subformat.
5112 */
5113 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5114 {
5115 MD5_CTX ctx;
5116 uint8_t digest[16];
5117 uint8_t *last;
5118 size_t d = 0;
5119 uint16_t m = htons(type);
5120
5121 // Compute initial pad
5122 MD5_Init(&ctx);
5123 MD5_Update(&ctx, (unsigned char *) &m, 2);
5124 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5125 MD5_Update(&ctx, vector, vec_len);
5126 MD5_Final(digest, &ctx);
5127
5128 // pointer to last decoded 16 octets
5129 last = value;
5130
5131 while (len > 0)
5132 {
5133 // calculate a new pad based on the last decoded block
5134 if (d >= sizeof(digest))
5135 {
5136 MD5_Init(&ctx);
5137 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5138 MD5_Update(&ctx, last, sizeof(digest));
5139 MD5_Final(digest, &ctx);
5140
5141 d = 0;
5142 last = value;
5143 }
5144
5145 *value++ ^= digest[d++];
5146 len--;
5147 }
5148 }
5149
5150 int find_filter(char const *name, size_t len)
5151 {
5152 int free = -1;
5153 int i;
5154
5155 for (i = 0; i < MAXFILTER; i++)
5156 {
5157 if (!*ip_filters[i].name)
5158 {
5159 if (free < 0)
5160 free = i;
5161
5162 continue;
5163 }
5164
5165 if (strlen(ip_filters[i].name) != len)
5166 continue;
5167
5168 if (!strncmp(ip_filters[i].name, name, len))
5169 return i;
5170 }
5171
5172 return free;
5173 }
5174
5175 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5176 {
5177 switch (p->op)
5178 {
5179 case FILTER_PORT_OP_EQ: return port == p->port;
5180 case FILTER_PORT_OP_NEQ: return port != p->port;
5181 case FILTER_PORT_OP_GT: return port > p->port;
5182 case FILTER_PORT_OP_LT: return port < p->port;
5183 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5184 }
5185
5186 return 0;
5187 }
5188
5189 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5190 {
5191 switch (op)
5192 {
5193 case FILTER_FLAG_OP_ANY:
5194 return (flags & sflags) || (~flags & cflags);
5195
5196 case FILTER_FLAG_OP_ALL:
5197 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5198
5199 case FILTER_FLAG_OP_EST:
5200 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5201 }
5202
5203 return 0;
5204 }
5205
5206 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5207 {
5208 uint16_t frag_offset;
5209 uint8_t proto;
5210 in_addr_t src_ip;
5211 in_addr_t dst_ip;
5212 uint16_t src_port = 0;
5213 uint16_t dst_port = 0;
5214 uint8_t flags = 0;
5215 ip_filter_rulet *rule;
5216
5217 if (len < 20) // up to end of destination address
5218 return 0;
5219
5220 if ((*buf >> 4) != 4) // IPv4
5221 return 0;
5222
5223 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5224 proto = buf[9];
5225 src_ip = *(in_addr_t *) (buf + 12);
5226 dst_ip = *(in_addr_t *) (buf + 16);
5227
5228 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5229 {
5230 int l = (buf[0] & 0xf) * 4; // length of IP header
5231 if (len < l + 4) // ports
5232 return 0;
5233
5234 src_port = ntohs(*(uint16_t *) (buf + l));
5235 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5236 if (proto == IPPROTO_TCP)
5237 {
5238 if (len < l + 14) // flags
5239 return 0;
5240
5241 flags = buf[l + 13] & 0x3f;
5242 }
5243 }
5244
5245 for (rule = ip_filters[filter].rules; rule->action; rule++)
5246 {
5247 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5248 continue;
5249
5250 if (rule->src_wild != INADDR_BROADCAST &&
5251 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5252 continue;
5253
5254 if (rule->dst_wild != INADDR_BROADCAST &&
5255 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5256 continue;
5257
5258 if (frag_offset)
5259 {
5260 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5261 continue;
5262 }
5263 else
5264 {
5265 if (rule->frag)
5266 continue;
5267
5268 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5269 {
5270 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5271 continue;
5272
5273 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5274 continue;
5275
5276 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5277 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5278 continue;
5279 }
5280 }
5281
5282 // matched
5283 rule->counter++;
5284 return rule->action == FILTER_ACTION_PERMIT;
5285 }
5286
5287 // default deny
5288 return 0;
5289 }