45ed04f5714f552f3ee3a6a6454c5448228f3da2
[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 1.113 2005/06/28 14:48:20 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("primary_dns", default_dns1, IPv4),
109 CONFIG("secondary_dns", default_dns2, IPv4),
110 CONFIG("primary_radius", radiusserver[0], IPv4),
111 CONFIG("secondary_radius", radiusserver[1], IPv4),
112 CONFIG("primary_radius_port", radiusport[0], SHORT),
113 CONFIG("secondary_radius_port", radiusport[1], SHORT),
114 CONFIG("radius_accounting", radius_accounting, BOOL),
115 CONFIG("radius_interim", radius_interim, INT),
116 CONFIG("radius_secret", radiussecret, STRING),
117 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
118 CONFIG("radius_dae_port", radius_dae_port, SHORT),
119 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
120 CONFIG("bind_address", bind_address, IPv4),
121 CONFIG("peer_address", peer_address, IPv4),
122 CONFIG("send_garp", send_garp, BOOL),
123 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
124 CONFIG("throttle_buckets", num_tbfs, INT),
125 CONFIG("accounting_dir", accounting_dir, STRING),
126 CONFIG("setuid", target_uid, INT),
127 CONFIG("dump_speed", dump_speed, BOOL),
128 CONFIG("multi_read_count", multi_read_count, INT),
129 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
130 CONFIG("lock_pages", lock_pages, BOOL),
131 CONFIG("icmp_rate", icmp_rate, INT),
132 CONFIG("packet_limit", max_packets, INT),
133 CONFIG("cluster_address", cluster_address, IPv4),
134 CONFIG("cluster_interface", cluster_interface, STRING),
135 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
136 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
137 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
138 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
139 { NULL, 0, 0, 0 },
140 };
141
142 static char *plugin_functions[] = {
143 NULL,
144 "plugin_pre_auth",
145 "plugin_post_auth",
146 "plugin_packet_rx",
147 "plugin_packet_tx",
148 "plugin_timer",
149 "plugin_new_session",
150 "plugin_kill_session",
151 "plugin_control",
152 "plugin_radius_response",
153 "plugin_radius_reset",
154 "plugin_become_master",
155 "plugin_new_session_master",
156 };
157
158 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
159
160 // Counters for shutdown sessions
161 static sessiont shut_acct[8192];
162 static sessionidt shut_acct_n = 0;
163
164 tunnelt *tunnel = NULL; // Array of tunnel structures.
165 sessiont *session = NULL; // Array of session structures.
166 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
167 radiust *radius = NULL; // Array of radius structures.
168 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
169 ip_filtert *ip_filters = NULL; // Array of named filters.
170 static controlt *controlfree = 0;
171 struct Tstats *_statistics = NULL;
172 #ifdef RINGBUFFER
173 struct Tringbuffer *ringbuffer = NULL;
174 #endif
175
176 static void cache_ipmap(in_addr_t ip, int s);
177 static void uncache_ipmap(in_addr_t ip);
178 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
179 static void free_ip_address(sessionidt s);
180 static void dump_acct_info(int all);
181 static void sighup_handler(int sig);
182 static void sigalrm_handler(int sig);
183 static void shutdown_handler(int sig);
184 static void sigchild_handler(int sig);
185 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
186 static void update_config(void);
187 static void read_config_file(void);
188 static void initplugins(void);
189 static int add_plugin(char *plugin_name);
190 static int remove_plugin(char *plugin_name);
191 static void plugins_done(void);
192 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
193 static tunnelidt new_tunnel(void);
194 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
195
196 // on slaves, alow BGP to withdraw cleanly before exiting
197 #define QUIT_DELAY 5
198
199 // quit actions (master)
200 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
201 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
202
203 // return internal time (10ths since process startup), set f if given
204 static clockt now(double *f)
205 {
206 struct timeval t;
207 gettimeofday(&t, 0);
208 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
209 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
210 }
211
212 // work out a retry time based on try number
213 // This is a straight bounded exponential backoff.
214 // Maximum re-try time is 32 seconds. (2^5).
215 clockt backoff(uint8_t try)
216 {
217 if (try > 5) try = 5; // max backoff
218 return now(NULL) + 10 * (1 << try);
219 }
220
221
222 //
223 // Log a debug message. Typically called via the LOG macro
224 //
225 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
226 {
227 static char message[65536] = {0};
228 va_list ap;
229
230 #ifdef RINGBUFFER
231 if (ringbuffer)
232 {
233 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
234 ringbuffer->tail = 0;
235 if (ringbuffer->tail == ringbuffer->head)
236 if (++ringbuffer->head >= RINGBUFFER_SIZE)
237 ringbuffer->head = 0;
238
239 ringbuffer->buffer[ringbuffer->tail].level = level;
240 ringbuffer->buffer[ringbuffer->tail].session = s;
241 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
242 va_start(ap, format);
243 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
244 va_end(ap);
245 }
246 #endif
247
248 if (config->debug < level) return;
249
250 va_start(ap, format);
251 vsnprintf(message, sizeof(message), format, ap);
252
253 if (log_stream)
254 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
255 else if (syslog_log)
256 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
257
258 va_end(ap);
259 }
260
261 void _log_hex(int level, const char *title, const char *data, int maxsize)
262 {
263 int i, j;
264 const uint8_t *d = (const uint8_t *) data;
265
266 if (config->debug < level) return;
267
268 // No support for _log_hex to syslog
269 if (log_stream)
270 {
271 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
272 setvbuf(log_stream, NULL, _IOFBF, 16384);
273
274 for (i = 0; i < maxsize; )
275 {
276 fprintf(log_stream, "%4X: ", i);
277 for (j = i; j < maxsize && j < (i + 16); j++)
278 {
279 fprintf(log_stream, "%02X ", d[j]);
280 if (j == i + 7)
281 fputs(": ", log_stream);
282 }
283
284 for (; j < i + 16; j++)
285 {
286 fputs(" ", log_stream);
287 if (j == i + 7)
288 fputs(": ", log_stream);
289 }
290
291 fputs(" ", log_stream);
292 for (j = i; j < maxsize && j < (i + 16); j++)
293 {
294 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
295 fputc(d[j], log_stream);
296 else
297 fputc('.', log_stream);
298
299 if (j == i + 7)
300 fputs(" ", log_stream);
301 }
302
303 i = j;
304 fputs("\n", log_stream);
305 }
306
307 fflush(log_stream);
308 setbuf(log_stream, NULL);
309 }
310 }
311
312 // update a counter, accumulating 2^32 wraps
313 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
314 {
315 uint32_t new = *counter + delta;
316 if (new < *counter)
317 (*wrap)++;
318
319 *counter = new;
320 }
321
322 // initialise the random generator
323 static void initrandom(char *source)
324 {
325 static char path[sizeof(config->random_device)] = "*undefined*";
326
327 // reinitialise only if we are forced to do so or if the config has changed
328 if (source && !strncmp(path, source, sizeof(path)))
329 return;
330
331 // close previous source, if any
332 if (rand_fd >= 0)
333 close(rand_fd);
334
335 rand_fd = -1;
336
337 if (source)
338 {
339 // register changes
340 snprintf(path, sizeof(path), "%s", source);
341
342 if (*path == '/')
343 {
344 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
345 if (rand_fd < 0)
346 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
347 path, strerror(errno));
348 }
349 }
350 }
351
352 // fill buffer with random data
353 void random_data(uint8_t *buf, int len)
354 {
355 int n = 0;
356
357 CSTAT(random_data);
358 if (rand_fd >= 0)
359 {
360 n = read(rand_fd, buf, len);
361 if (n >= len) return;
362 if (n < 0)
363 {
364 if (errno != EAGAIN)
365 {
366 LOG(0, 0, 0, "Error reading from random source: %s\n",
367 strerror(errno));
368
369 // fall back to rand()
370 initrandom(NULL);
371 }
372
373 n = 0;
374 }
375 }
376
377 // append missing data
378 while (n < len)
379 // not using the low order bits from the prng stream
380 buf[n++] = (rand() >> 4) & 0xff;
381 }
382
383 // Add a route
384 //
385 // This adds it to the routing table, advertises it
386 // via BGP if enabled, and stuffs it into the
387 // 'sessionbyip' cache.
388 //
389 // 'ip' and 'mask' must be in _host_ order.
390 //
391 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
392 {
393 struct rtentry r;
394 int i;
395
396 if (!mask) mask = 0xffffffff;
397
398 ip &= mask; // Force the ip to be the first one in the route.
399
400 memset(&r, 0, sizeof(r));
401 r.rt_dev = config->tundevice;
402 r.rt_dst.sa_family = AF_INET;
403 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
404 r.rt_gateway.sa_family = AF_INET;
405 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
406 r.rt_genmask.sa_family = AF_INET;
407 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
408 r.rt_flags = (RTF_UP | RTF_STATIC);
409 if (gw)
410 r.rt_flags |= RTF_GATEWAY;
411 else if (mask == 0xffffffff)
412 r.rt_flags |= RTF_HOST;
413
414 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
415 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
416 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
417
418 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
419 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
420
421 #ifdef BGP
422 if (add)
423 bgp_add_route(htonl(ip), htonl(mask));
424 else
425 bgp_del_route(htonl(ip), htonl(mask));
426 #endif /* BGP */
427
428 // Add/Remove the IPs to the 'sessionbyip' cache.
429 // Note that we add the zero address in the case of
430 // a network route. Roll on CIDR.
431
432 // Note that 's == 0' implies this is the address pool.
433 // We still cache it here, because it will pre-fill
434 // the malloc'ed tree.
435
436 if (s)
437 {
438 if (!add) // Are we deleting a route?
439 s = 0; // Caching the session as '0' is the same as uncaching.
440
441 for (i = ip; (i&mask) == (ip&mask) ; ++i)
442 cache_ipmap(i, s);
443 }
444 }
445
446 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
447 {
448 struct in6_rtmsg rt;
449 char ipv6addr[INET6_ADDRSTRLEN];
450
451 if (ifr6fd < 0)
452 {
453 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
454 return;
455 }
456
457 memset(&rt, 0, sizeof(rt));
458
459 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
460 rt.rtmsg_dst_len = prefixlen;
461 rt.rtmsg_metric = 1;
462 rt.rtmsg_flags = RTF_UP;
463 rt.rtmsg_ifindex = tunidx;
464
465 LOG(1, 0, 0, "Route %s %s/%d\n",
466 add ? "add" : "del",
467 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
468 prefixlen);
469
470 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
471 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
472 strerror(errno));
473
474 // FIXME: need to add BGP routing (RFC2858)
475
476 if (s)
477 {
478 if (!add) // Are we deleting a route?
479 s = 0; // Caching the session as '0' is the same as uncaching.
480
481 cache_ipv6map(ip, prefixlen, s);
482 }
483
484 return;
485 }
486
487 // defined in linux/ipv6.h, but tricky to include from user-space
488 // TODO: move routing to use netlink rather than ioctl
489 struct in6_ifreq {
490 struct in6_addr ifr6_addr;
491 __u32 ifr6_prefixlen;
492 unsigned int ifr6_ifindex;
493 };
494
495 //
496 // Set up TUN interface
497 static void inittun(void)
498 {
499 struct ifreq ifr;
500 struct in6_ifreq ifr6;
501 struct sockaddr_in sin = {0};
502 memset(&ifr, 0, sizeof(ifr));
503 ifr.ifr_flags = IFF_TUN;
504
505 tunfd = open(TUNDEVICE, O_RDWR);
506 if (tunfd < 0)
507 { // fatal
508 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
509 exit(1);
510 }
511 {
512 int flags = fcntl(tunfd, F_GETFL, 0);
513 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
514 }
515 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
516 {
517 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
518 exit(1);
519 }
520 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
521 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
522 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
523
524 sin.sin_family = AF_INET;
525 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
526 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
527
528 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
529 {
530 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
531 exit(1);
532 }
533 /* Bump up the qlen to deal with bursts from the network */
534 ifr.ifr_qlen = 1000;
535 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
536 {
537 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
538 exit(1);
539 }
540 ifr.ifr_flags = IFF_UP;
541 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
542 {
543 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
544 exit(1);
545 }
546 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
547 {
548 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
549 exit(1);
550 }
551 tunidx = ifr.ifr_ifindex;
552
553 // Only setup IPv6 on the tun device if we have a configured prefix
554 if (config->ipv6_prefix.s6_addr[0] > 0) {
555 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
556
557 // Link local address is FE80::1
558 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
559 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
560 ifr6.ifr6_addr.s6_addr[1] = 0x80;
561 ifr6.ifr6_addr.s6_addr[15] = 1;
562 ifr6.ifr6_prefixlen = 64;
563 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
564 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
565 {
566 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
567 " %s\n", strerror(errno));
568 }
569
570 // Global address is prefix::1
571 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
572 ifr6.ifr6_addr = config->ipv6_prefix;
573 ifr6.ifr6_addr.s6_addr[15] = 1;
574 ifr6.ifr6_prefixlen = 64;
575 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
576 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
577 {
578 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
579 strerror(errno));
580 }
581 }
582 }
583
584 // set up UDP ports
585 static void initudp(void)
586 {
587 int on = 1;
588 struct sockaddr_in addr;
589
590 // Tunnel
591 memset(&addr, 0, sizeof(addr));
592 addr.sin_family = AF_INET;
593 addr.sin_port = htons(L2TPPORT);
594 addr.sin_addr.s_addr = config->bind_address;
595 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
596 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
597 {
598 int flags = fcntl(udpfd, F_GETFL, 0);
599 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
600 }
601 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
602 {
603 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
604 exit(1);
605 }
606
607 // Control
608 memset(&addr, 0, sizeof(addr));
609 addr.sin_family = AF_INET;
610 addr.sin_port = htons(NSCTL_PORT);
611 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
612 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
613 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
614 {
615 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
616 exit(1);
617 }
618
619 // Dynamic Authorization Extensions to RADIUS
620 memset(&addr, 0, sizeof(addr));
621 addr.sin_family = AF_INET;
622 addr.sin_port = htons(config->radius_dae_port);
623 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
624 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
625 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
626 {
627 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
628 exit(1);
629 }
630
631 // Intercept
632 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
633 }
634
635 //
636 // Find session by IP, < 1 for not found
637 //
638 // Confusingly enough, this 'ip' must be
639 // in _network_ order. This being the common
640 // case when looking it up from IP packet headers.
641 //
642 // We actually use this cache for two things.
643 // #1. For used IP addresses, this maps to the
644 // session ID that it's used by.
645 // #2. For un-used IP addresses, this maps to the
646 // index into the pool table that contains that
647 // IP address.
648 //
649
650 static int lookup_ipmap(in_addr_t ip)
651 {
652 uint8_t *a = (uint8_t *) &ip;
653 uint8_t **d = (uint8_t **) ip_hash;
654
655 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
656 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
657 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
658
659 return (int) (intptr_t) d[(size_t) *a];
660 }
661
662 static int lookup_ipv6map(struct in6_addr ip)
663 {
664 struct ipv6radix *curnode;
665 int i;
666 int s;
667 char ipv6addr[INET6_ADDRSTRLEN];
668
669 curnode = &ipv6_hash[ip.s6_addr[0]];
670 i = 1;
671 s = curnode->sess;
672
673 while (s == 0 && i < 15 && curnode->branch != NULL)
674 {
675 curnode = &curnode->branch[ip.s6_addr[i]];
676 s = curnode->sess;
677 i++;
678 }
679
680 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
681 inet_ntop(AF_INET6, &ip, ipv6addr,
682 INET6_ADDRSTRLEN),
683 s);
684
685 return s;
686 }
687
688 sessionidt sessionbyip(in_addr_t ip)
689 {
690 int s = lookup_ipmap(ip);
691 CSTAT(sessionbyip);
692
693 if (s > 0 && s < MAXSESSION && session[s].opened)
694 return (sessionidt) s;
695
696 return 0;
697 }
698
699 sessionidt sessionbyipv6(struct in6_addr ip)
700 {
701 int s;
702 CSTAT(sessionbyipv6);
703
704 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
705 (ip.s6_addr[0] == 0xFE && ip.s6_addr[1] == 0x80 &&
706 (ip.s6_addr16[1] == ip.s6_addr16[2] == ip.s6_addr16[3] == 0))) {
707 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
708 } else {
709 s = lookup_ipv6map(ip);
710 }
711
712 if (s > 0 && s < MAXSESSION && session[s].opened)
713 return s;
714
715 return 0;
716 }
717
718 //
719 // Take an IP address in HOST byte order and
720 // add it to the sessionid by IP cache.
721 //
722 // (It's actually cached in network order)
723 //
724 static void cache_ipmap(in_addr_t ip, int s)
725 {
726 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
727 uint8_t *a = (uint8_t *) &nip;
728 uint8_t **d = (uint8_t **) ip_hash;
729 int i;
730
731 for (i = 0; i < 3; i++)
732 {
733 if (!d[(size_t) a[i]])
734 {
735 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
736 return;
737 }
738
739 d = (uint8_t **) d[(size_t) a[i]];
740 }
741
742 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
743
744 if (s > 0)
745 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
746
747 else if (s == 0)
748 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
749 // else a map to an ip pool index.
750 }
751
752 static void uncache_ipmap(in_addr_t ip)
753 {
754 cache_ipmap(ip, 0); // Assign it to the NULL session.
755 }
756
757 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
758 {
759 int i;
760 int bytes;
761 struct ipv6radix *curnode;
762 char ipv6addr[INET6_ADDRSTRLEN];
763
764 curnode = &ipv6_hash[ip.s6_addr[0]];
765
766 bytes = prefixlen >> 3;
767 i = 1;
768 while (i < bytes) {
769 if (curnode->branch == NULL)
770 {
771 if (!(curnode->branch = calloc(256,
772 sizeof (struct ipv6radix))))
773 return;
774 }
775 curnode = &curnode->branch[ip.s6_addr[i]];
776 i++;
777 }
778
779 curnode->sess = s;
780
781 if (s > 0)
782 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
783 inet_ntop(AF_INET6, &ip, ipv6addr,
784 INET6_ADDRSTRLEN),
785 prefixlen);
786 else if (s == 0)
787 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
788 inet_ntop(AF_INET6, &ip, ipv6addr,
789 INET6_ADDRSTRLEN),
790 prefixlen);
791 }
792
793 //
794 // CLI list to dump current ipcache.
795 //
796 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
797 {
798 char **d = (char **) ip_hash, **e, **f, **g;
799 int i, j, k, l;
800 int count = 0;
801
802 if (CLI_HELP_REQUESTED)
803 return CLI_HELP_NO_ARGS;
804
805 cli_print(cli, "%7s %s", "Sess#", "IP Address");
806
807 for (i = 0; i < 256; ++i)
808 {
809 if (!d[i])
810 continue;
811 e = (char **) d[i];
812 for (j = 0; j < 256; ++j)
813 {
814 if (!e[j])
815 continue;
816 f = (char **) e[j];
817 for (k = 0; k < 256; ++k)
818 {
819 if (!f[k])
820 continue;
821 g = (char **)f[k];
822 for (l = 0; l < 256; ++l)
823 {
824 if (!g[l])
825 continue;
826 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
827 ++count;
828 }
829 }
830 }
831 }
832 cli_print(cli, "%d entries in cache", count);
833 return CLI_OK;
834 }
835
836
837 // Find session by username, 0 for not found
838 // walled garden users aren't authenticated, so the username is
839 // reasonably useless. Ignore them to avoid incorrect actions
840 //
841 // This is VERY inefficent. Don't call it often. :)
842 //
843 sessionidt sessionbyuser(char *username)
844 {
845 int s;
846 CSTAT(sessionbyuser);
847
848 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
849 {
850 if (!session[s].opened)
851 continue;
852
853 if (session[s].walled_garden)
854 continue; // Skip walled garden users.
855
856 if (!strncmp(session[s].user, username, 128))
857 return s;
858
859 }
860 return 0; // Not found.
861 }
862
863 void send_garp(in_addr_t ip)
864 {
865 int s;
866 struct ifreq ifr;
867 uint8_t mac[6];
868
869 s = socket(PF_INET, SOCK_DGRAM, 0);
870 if (s < 0)
871 {
872 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
873 return;
874 }
875 memset(&ifr, 0, sizeof(ifr));
876 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
877 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
878 {
879 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
880 close(s);
881 return;
882 }
883 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
884 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
885 {
886 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
887 close(s);
888 return;
889 }
890 close(s);
891 sendarp(ifr.ifr_ifindex, mac, ip);
892 }
893
894 static sessiont *sessiontbysessionidt(sessionidt s)
895 {
896 if (!s || s >= MAXSESSION) return NULL;
897 return &session[s];
898 }
899
900 static sessionidt sessionidtbysessiont(sessiont *s)
901 {
902 sessionidt val = s-session;
903 if (s < session || val >= MAXSESSION) return 0;
904 return val;
905 }
906
907 // actually send a control message for a specific tunnel
908 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
909 {
910 struct sockaddr_in addr;
911
912 CSTAT(tunnelsend);
913
914 if (!t)
915 {
916 static int backtrace_count = 0;
917 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
918 STAT(tunnel_tx_errors);
919 log_backtrace(backtrace_count, 5)
920 return;
921 }
922
923 if (!tunnel[t].ip)
924 {
925 static int backtrace_count = 0;
926 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
927 log_backtrace(backtrace_count, 5)
928 STAT(tunnel_tx_errors);
929 return;
930 }
931
932 memset(&addr, 0, sizeof(addr));
933 addr.sin_family = AF_INET;
934 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
935 addr.sin_port = htons(tunnel[t].port);
936
937 // sequence expected, if sequence in message
938 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
939
940 // If this is a control message, deal with retries
941 if (*buf & 0x80)
942 {
943 tunnel[t].last = time_now; // control message sent
944 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
945 if (tunnel[t].try > 1)
946 {
947 STAT(tunnel_retries);
948 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
949 }
950 }
951
952 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
953 {
954 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
955 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
956 STAT(tunnel_tx_errors);
957 return;
958 }
959
960 LOG_HEX(5, "Send Tunnel Data", buf, l);
961 STAT(tunnel_tx_packets);
962 INC_STAT(tunnel_tx_bytes, l);
963 }
964
965 //
966 // Tiny helper function to write data to
967 // the 'tun' device.
968 //
969 int tun_write(uint8_t * data, int size)
970 {
971 return write(tunfd, data, size);
972 }
973
974 // process outgoing (to tunnel) IP
975 //
976 static void processipout(uint8_t * buf, int len)
977 {
978 sessionidt s;
979 sessiont *sp;
980 tunnelidt t;
981 in_addr_t ip;
982
983 char *data = buf; // Keep a copy of the originals.
984 int size = len;
985
986 uint8_t b[MAXETHER + 20];
987
988 CSTAT(processipout);
989
990 if (len < MIN_IP_SIZE)
991 {
992 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
993 STAT(tun_rx_errors);
994 return;
995 }
996 if (len >= MAXETHER)
997 {
998 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
999 STAT(tun_rx_errors);
1000 return;
1001 }
1002
1003 // Skip the tun header
1004 buf += 4;
1005 len -= 4;
1006
1007 // Got an IP header now
1008 if (*(uint8_t *)(buf) >> 4 != 4)
1009 {
1010 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1011 return;
1012 }
1013
1014 ip = *(uint32_t *)(buf + 16);
1015 if (!(s = sessionbyip(ip)))
1016 {
1017 // Is this a packet for a session that doesn't exist?
1018 static int rate = 0; // Number of ICMP packets we've sent this second.
1019 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1020
1021 if (last != time_now)
1022 {
1023 last = time_now;
1024 rate = 0;
1025 }
1026
1027 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1028 {
1029 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1030 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1031 config->bind_address ? config->bind_address : my_address, buf, len);
1032 }
1033 return;
1034 }
1035 t = session[s].tunnel;
1036 sp = &session[s];
1037
1038 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1039 if (config->max_packets > 0)
1040 {
1041 if (sess_local[s].last_packet_out == TIME)
1042 {
1043 int max = config->max_packets;
1044
1045 // All packets for throttled sessions are handled by the
1046 // master, so further limit by using the throttle rate.
1047 // A bit of a kludge, since throttle rate is in kbps,
1048 // but should still be generous given our average DSL
1049 // packet size is 200 bytes: a limit of 28kbps equates
1050 // to around 180 packets per second.
1051 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1052 max = sp->throttle_out;
1053
1054 if (++sess_local[s].packets_out > max)
1055 {
1056 sess_local[s].packets_dropped++;
1057 return;
1058 }
1059 }
1060 else
1061 {
1062 if (sess_local[s].packets_dropped)
1063 {
1064 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1065 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1066 sess_local[s].packets_dropped, sess_local[s].packets_out,
1067 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1068 sp->user);
1069 }
1070
1071 sess_local[s].last_packet_out = TIME;
1072 sess_local[s].packets_out = 1;
1073 sess_local[s].packets_dropped = 0;
1074 }
1075 }
1076
1077 // run access-list if any
1078 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1079 return;
1080
1081 if (sp->tbf_out)
1082 {
1083 // Are we throttling this session?
1084 if (config->cluster_iam_master)
1085 tbf_queue_packet(sp->tbf_out, data, size);
1086 else
1087 master_throttle_packet(sp->tbf_out, data, size);
1088 return;
1089 }
1090 else if (sp->walled_garden && !config->cluster_iam_master)
1091 {
1092 // We are walled-gardening this
1093 master_garden_packet(s, data, size);
1094 return;
1095 }
1096
1097 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1098
1099 // Add on L2TP header
1100 {
1101 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1102 if (!p) return;
1103 tunnelsend(b, len + (p-b), t); // send it...
1104 }
1105
1106 // Snooping this session, send it to intercept box
1107 if (sp->snoop_ip && sp->snoop_port)
1108 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1109
1110 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1111 sp->cout_delta += len;
1112 sp->pout++;
1113 udp_tx += len;
1114
1115 sess_local[s].cout += len; // To send to master..
1116 sess_local[s].pout++;
1117 }
1118
1119 // process outgoing (to tunnel) IPv6
1120 //
1121 static void processipv6out(uint8_t * buf, int len)
1122 {
1123 sessionidt s;
1124 sessiont *sp;
1125 tunnelidt t;
1126 in_addr_t ip;
1127 struct in6_addr ip6;
1128
1129 char *data = buf; // Keep a copy of the originals.
1130 int size = len;
1131
1132 uint8_t b[MAXETHER + 20];
1133
1134 CSTAT(processipv6out);
1135
1136 if (len < MIN_IP_SIZE)
1137 {
1138 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1139 STAT(tunnel_tx_errors);
1140 return;
1141 }
1142 if (len >= MAXETHER)
1143 {
1144 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1145 STAT(tunnel_tx_errors);
1146 return;
1147 }
1148
1149 // Skip the tun header
1150 buf += 4;
1151 len -= 4;
1152
1153 // Got an IP header now
1154 if (*(uint8_t *)(buf) >> 4 != 6)
1155 {
1156 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1157 return;
1158 }
1159
1160 ip6 = *(struct in6_addr *)(buf+24);
1161 s = sessionbyipv6(ip6);
1162
1163 if (s == 0)
1164 {
1165 ip = *(uint32_t *)(buf + 32);
1166 s = sessionbyip(ip);
1167 }
1168
1169 if (s == 0)
1170 {
1171 // Is this a packet for a session that doesn't exist?
1172 static int rate = 0; // Number of ICMP packets we've sent this second.
1173 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1174
1175 if (last != time_now)
1176 {
1177 last = time_now;
1178 rate = 0;
1179 }
1180
1181 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1182 {
1183 // FIXME: Should send icmp6 host unreachable
1184 }
1185 return;
1186 }
1187 t = session[s].tunnel;
1188 sp = &session[s];
1189
1190 // FIXME: add DoS prevention/filters?
1191
1192 if (sp->tbf_out)
1193 {
1194 // Are we throttling this session?
1195 if (config->cluster_iam_master)
1196 tbf_queue_packet(sp->tbf_out, data, size);
1197 else
1198 master_throttle_packet(sp->tbf_out, data, size);
1199 return;
1200 }
1201 else if (sp->walled_garden && !config->cluster_iam_master)
1202 {
1203 // We are walled-gardening this
1204 master_garden_packet(s, data, size);
1205 return;
1206 }
1207
1208 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1209
1210 // Add on L2TP header
1211 {
1212 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIPV6);
1213 if (!p) return;
1214 tunnelsend(b, len + (p-b), t); // send it...
1215 }
1216
1217 // Snooping this session, send it to intercept box
1218 if (sp->snoop_ip && sp->snoop_port)
1219 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1220
1221 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1222 sp->cout_delta += len;
1223 sp->pout++;
1224 udp_tx += len;
1225
1226 sess_local[s].cout += len; // To send to master..
1227 sess_local[s].pout++;
1228 }
1229
1230 //
1231 // Helper routine for the TBF filters.
1232 // Used to send queued data in to the user!
1233 //
1234 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1235 {
1236 sessiont *sp;
1237 tunnelidt t;
1238 in_addr_t ip;
1239
1240 uint8_t b[MAXETHER + 20];
1241
1242 if (len < 0 || len > MAXETHER)
1243 {
1244 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1245 return;
1246 }
1247
1248 // Skip the tun header
1249 buf += 4;
1250 len -= 4;
1251
1252 ip = *(in_addr_t *)(buf + 16);
1253
1254 if (!session[s].ip)
1255 return;
1256
1257 t = session[s].tunnel;
1258 sp = &session[s];
1259
1260 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1261
1262 // Add on L2TP header
1263 {
1264 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1265 if (!p) return;
1266 tunnelsend(b, len + (p-b), t); // send it...
1267 }
1268
1269 // Snooping this session.
1270 if (sp->snoop_ip && sp->snoop_port)
1271 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1272
1273 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1274 sp->cout_delta += len;
1275 sp->pout++;
1276 udp_tx += len;
1277
1278 sess_local[s].cout += len; // To send to master..
1279 sess_local[s].pout++;
1280 }
1281
1282 // add an AVP (16 bit)
1283 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1284 {
1285 uint16_t l = (m ? 0x8008 : 0x0008);
1286 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1287 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1288 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1289 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1290 c->length += 8;
1291 }
1292
1293 // add an AVP (32 bit)
1294 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1295 {
1296 uint16_t l = (m ? 0x800A : 0x000A);
1297 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1298 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1299 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1300 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1301 c->length += 10;
1302 }
1303
1304 // add an AVP (string)
1305 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1306 {
1307 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1308 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1309 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1310 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1311 memcpy(c->buf + c->length + 6, val, strlen(val));
1312 c->length += 6 + strlen(val);
1313 }
1314
1315 // add a binary AVP
1316 static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
1317 {
1318 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1319 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1320 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1321 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1322 memcpy(c->buf + c->length + 6, val, len);
1323 c->length += 6 + len;
1324 }
1325
1326 // new control connection
1327 static controlt *controlnew(uint16_t mtype)
1328 {
1329 controlt *c;
1330 if (!controlfree)
1331 c = malloc(sizeof(controlt));
1332 else
1333 {
1334 c = controlfree;
1335 controlfree = c->next;
1336 }
1337 assert(c);
1338 c->next = 0;
1339 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1340 c->length = 12;
1341 control16(c, 0, mtype, 1);
1342 return c;
1343 }
1344
1345 // send zero block if nothing is waiting
1346 // (ZLB send).
1347 static void controlnull(tunnelidt t)
1348 {
1349 uint8_t buf[12];
1350 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1351 return;
1352
1353 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1354 *(uint16_t *) (buf + 2) = htons(12); // length
1355 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1356 *(uint16_t *) (buf + 6) = htons(0); // session
1357 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1358 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1359 tunnelsend(buf, 12, t);
1360 }
1361
1362 // add a control message to a tunnel, and send if within window
1363 static void controladd(controlt * c, tunnelidt t, sessionidt far)
1364 {
1365 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1366 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1367 *(uint16_t *) (c->buf + 6) = htons(far); // session
1368 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1369 tunnel[t].ns++; // advance sequence
1370 // link in message in to queue
1371 if (tunnel[t].controlc)
1372 tunnel[t].controle->next = c;
1373 else
1374 tunnel[t].controls = c;
1375
1376 tunnel[t].controle = c;
1377 tunnel[t].controlc++;
1378
1379 // send now if space in window
1380 if (tunnel[t].controlc <= tunnel[t].window)
1381 {
1382 tunnel[t].try = 0; // first send
1383 tunnelsend(c->buf, c->length, t);
1384 }
1385 }
1386
1387 //
1388 // Throttle or Unthrottle a session
1389 //
1390 // Throttle the data from/to through a session to no more than
1391 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1392 // user).
1393 //
1394 // If either value is -1, the current value is retained for that
1395 // direction.
1396 //
1397 void throttle_session(sessionidt s, int rate_in, int rate_out)
1398 {
1399 if (!session[s].opened)
1400 return; // No-one home.
1401
1402 if (!*session[s].user)
1403 return; // User not logged in
1404
1405 if (rate_in >= 0)
1406 {
1407 int bytes = rate_in * 1024 / 8; // kbits to bytes
1408 if (session[s].tbf_in)
1409 free_tbf(session[s].tbf_in);
1410
1411 if (rate_in > 0)
1412 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1413 else
1414 session[s].tbf_in = 0;
1415
1416 session[s].throttle_in = rate_in;
1417 }
1418
1419 if (rate_out >= 0)
1420 {
1421 int bytes = rate_out * 1024 / 8;
1422 if (session[s].tbf_out)
1423 free_tbf(session[s].tbf_out);
1424
1425 if (rate_out > 0)
1426 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1427 else
1428 session[s].tbf_out = 0;
1429
1430 session[s].throttle_out = rate_out;
1431 }
1432 }
1433
1434 // add/remove filters from session (-1 = no change)
1435 void filter_session(sessionidt s, int filter_in, int filter_out)
1436 {
1437 if (!session[s].opened)
1438 return; // No-one home.
1439
1440 if (!*session[s].user)
1441 return; // User not logged in
1442
1443 // paranoia
1444 if (filter_in > MAXFILTER) filter_in = -1;
1445 if (filter_out > MAXFILTER) filter_out = -1;
1446 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1447 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1448
1449 if (filter_in >= 0)
1450 {
1451 if (session[s].filter_in)
1452 ip_filters[session[s].filter_in - 1].used--;
1453
1454 if (filter_in > 0)
1455 ip_filters[filter_in - 1].used++;
1456
1457 session[s].filter_in = filter_in;
1458 }
1459
1460 if (filter_out >= 0)
1461 {
1462 if (session[s].filter_out)
1463 ip_filters[session[s].filter_out - 1].used--;
1464
1465 if (filter_out > 0)
1466 ip_filters[filter_out - 1].used++;
1467
1468 session[s].filter_out = filter_out;
1469 }
1470 }
1471
1472 // start tidy shutdown of session
1473 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1474 {
1475 int walled_garden = session[s].walled_garden;
1476
1477
1478 CSTAT(sessionshutdown);
1479
1480 if (!session[s].opened)
1481 {
1482 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1483 return; // not a live session
1484 }
1485
1486 if (!session[s].die)
1487 {
1488 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1489 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1490 run_plugins(PLUGIN_KILL_SESSION, &data);
1491 }
1492
1493 if (session[s].ip && !walled_garden && !session[s].die)
1494 {
1495 // RADIUS Stop message
1496 uint16_t r = sess_local[s].radius;
1497 if (!r)
1498 r = radiusnew(s);
1499
1500 if (r)
1501 {
1502 // stop, if not already trying
1503 if (radius[r].state != RADIUSSTOP)
1504 radiussend(r, RADIUSSTOP);
1505 }
1506 else
1507 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1508
1509 // Save counters to dump to accounting file
1510 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1511 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1512 }
1513
1514 if (session[s].ip)
1515 { // IP allocated, clear and unroute
1516 int r;
1517 int routed = 0;
1518 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1519 {
1520 if ((session[s].ip & session[s].route[r].mask) ==
1521 (session[s].route[r].ip & session[s].route[r].mask))
1522 routed++;
1523
1524 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1525 session[s].route[r].ip = 0;
1526 }
1527
1528 if (session[s].ip_pool_index == -1) // static ip
1529 {
1530 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1531 session[s].ip = 0;
1532 }
1533 else
1534 free_ip_address(s);
1535
1536 // unroute IPv6, if setup
1537 if (session[s].flags & SF_IPV6_ROUTED)
1538 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1539 }
1540
1541 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1542 throttle_session(s, 0, 0);
1543
1544 if (result)
1545 { // Send CDN
1546 controlt *c = controlnew(14); // sending CDN
1547 if (error)
1548 {
1549 char buf[4];
1550 *(uint16_t *) buf = htons(result);
1551 *(uint16_t *) (buf+2) = htons(error);
1552 controlb(c, 1, buf, 4, 1);
1553 }
1554 else
1555 control16(c, 1, result, 1);
1556
1557 control16(c, 14, s, 1); // assigned session (our end)
1558 controladd(c, session[s].tunnel, session[s].far); // send the message
1559 }
1560
1561 if (!session[s].die)
1562 session[s].die = TIME + 150; // Clean up in 15 seconds
1563
1564 // update filter refcounts
1565 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1566 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1567
1568 cluster_send_session(s);
1569 }
1570
1571 void sendipcp(tunnelidt t, sessionidt s)
1572 {
1573 uint8_t buf[MAXCONTROL];
1574 uint16_t r = sess_local[s].radius;
1575 uint8_t *q;
1576
1577 CSTAT(sendipcp);
1578
1579 if (!r)
1580 r = radiusnew(s);
1581
1582 if (!r)
1583 {
1584 sessionshutdown(s, "No free RADIUS sessions for IPCP", 3, 0);
1585 return;
1586 }
1587
1588 if (radius[r].state != RADIUSIPCP)
1589 {
1590 radius[r].state = RADIUSIPCP;
1591 radius[r].try = 0;
1592 }
1593
1594 radius[r].retry = backoff(radius[r].try++);
1595 if (radius[r].try > 10)
1596 {
1597 radiusclear(r, s); // Clear radius session.
1598 sessionshutdown(s, "No reply to IPCP.", 3, 0);
1599 return;
1600 }
1601
1602 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1603 if (!q) return;
1604
1605 *q = ConfigReq;
1606 q[1] = r >> RADIUS_SHIFT; // ID, dont care, we only send one type of request
1607 *(uint16_t *) (q + 2) = htons(10);
1608 q[4] = 3;
1609 q[5] = 6;
1610 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1611 config->bind_address ? config->bind_address :
1612 my_address; // send my IP
1613
1614 tunnelsend(buf, 10 + (q - buf), t); // send it
1615 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1616
1617 // If we have an IPv6 prefix length configured, assume we should
1618 // try to negotiate an IPv6 session as well. Unless we've had a
1619 // (N)ACK for IPV6CP.
1620 if (config->ipv6_prefix.s6_addr[0] > 0 &&
1621 !(session[s].flags & SF_IPV6CP_ACKED) &&
1622 !(session[s].flags & SF_IPV6_NACKED))
1623 {
1624 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
1625 if (!q) return;
1626
1627 *q = ConfigReq;
1628 q[1] = r >> RADIUS_SHIFT; // ID, don't care, we
1629 // only send one type
1630 // of request
1631 *(uint16_t *) (q + 2) = htons(14);
1632 q[4] = 1;
1633 q[5] = 10;
1634 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1635 *(uint32_t *) (q + 10) = 0;
1636 q[13] = 1;
1637
1638 tunnelsend(buf, 14 + (q - buf), t); // send it
1639 }
1640 }
1641
1642 static void sessionclear(sessionidt s)
1643 {
1644 memset(&session[s], 0, sizeof(session[s]));
1645 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1646 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1647
1648 session[s].tunnel = T_FREE; // Mark it as free.
1649 session[s].next = sessionfree;
1650 sessionfree = s;
1651 }
1652
1653 // kill a session now
1654 void sessionkill(sessionidt s, char *reason)
1655 {
1656
1657 CSTAT(sessionkill);
1658
1659 if (!session[s].opened) // not alive
1660 return;
1661
1662 if (session[s].next)
1663 {
1664 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1665 return;
1666 }
1667
1668 session[s].die = TIME;
1669 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1670 if (sess_local[s].radius)
1671 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1672
1673 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1674 sessionclear(s);
1675 cluster_send_session(s);
1676 }
1677
1678 static void tunnelclear(tunnelidt t)
1679 {
1680 if (!t) return;
1681 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1682 tunnel[t].state = TUNNELFREE;
1683 }
1684
1685 // kill a tunnel now
1686 static void tunnelkill(tunnelidt t, char *reason)
1687 {
1688 sessionidt s;
1689 controlt *c;
1690
1691 CSTAT(tunnelkill);
1692
1693 tunnel[t].state = TUNNELDIE;
1694
1695 // free control messages
1696 while ((c = tunnel[t].controls))
1697 {
1698 controlt * n = c->next;
1699 tunnel[t].controls = n;
1700 tunnel[t].controlc--;
1701 c->next = controlfree;
1702 controlfree = c;
1703 }
1704 // kill sessions
1705 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1706 if (session[s].tunnel == t)
1707 sessionkill(s, reason);
1708
1709 // free tunnel
1710 tunnelclear(t);
1711 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1712 cli_tunnel_actions[t].action = 0;
1713 cluster_send_tunnel(t);
1714 }
1715
1716 // shut down a tunnel cleanly
1717 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1718 {
1719 sessionidt s;
1720
1721 CSTAT(tunnelshutdown);
1722
1723 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1724 {
1725 // never set up, can immediately kill
1726 tunnelkill(t, reason);
1727 return;
1728 }
1729 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1730
1731 // close session
1732 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1733 if (session[s].tunnel == t)
1734 sessionshutdown(s, reason, 0, 0);
1735
1736 tunnel[t].state = TUNNELDIE;
1737 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1738 cluster_send_tunnel(t);
1739 // TBA - should we wait for sessions to stop?
1740 if (result)
1741 {
1742 controlt *c = controlnew(4); // sending StopCCN
1743 if (error)
1744 {
1745 char buf[64];
1746 int l = 4;
1747 *(uint16_t *) buf = htons(result);
1748 *(uint16_t *) (buf+2) = htons(error);
1749 if (msg)
1750 {
1751 int m = strlen(msg);
1752 if (m + 4 > sizeof(buf))
1753 m = sizeof(buf) - 4;
1754
1755 memcpy(buf+4, msg, m);
1756 l += m;
1757 }
1758
1759 controlb(c, 1, buf, l, 1);
1760 }
1761 else
1762 control16(c, 1, result, 1);
1763
1764 control16(c, 9, t, 1); // assigned tunnel (our end)
1765 controladd(c, t, 0); // send the message
1766 }
1767 }
1768
1769 // read and process packet on tunnel (UDP)
1770 void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
1771 {
1772 char *chapresponse = NULL;
1773 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1774 uint8_t *p = buf + 2;
1775
1776
1777 CSTAT(processudp);
1778
1779 udp_rx += len;
1780 udp_rx_pkt++;
1781 LOG_HEX(5, "UDP Data", buf, len);
1782 STAT(tunnel_rx_packets);
1783 INC_STAT(tunnel_rx_bytes, len);
1784 if (len < 6)
1785 {
1786 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1787 STAT(tunnel_rx_errors);
1788 return;
1789 }
1790 if ((buf[1] & 0x0F) != 2)
1791 {
1792 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1793 STAT(tunnel_rx_errors);
1794 return;
1795 }
1796 if (*buf & 0x40)
1797 { // length
1798 l = ntohs(*(uint16_t *) p);
1799 p += 2;
1800 }
1801 t = ntohs(*(uint16_t *) p);
1802 p += 2;
1803 s = ntohs(*(uint16_t *) p);
1804 p += 2;
1805 if (s >= MAXSESSION)
1806 {
1807 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1808 STAT(tunnel_rx_errors);
1809 return;
1810 }
1811 if (t >= MAXTUNNEL)
1812 {
1813 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1814 STAT(tunnel_rx_errors);
1815 return;
1816 }
1817 if (*buf & 0x08)
1818 { // ns/nr
1819 ns = ntohs(*(uint16_t *) p);
1820 p += 2;
1821 nr = ntohs(*(uint16_t *) p);
1822 p += 2;
1823 }
1824 if (*buf & 0x02)
1825 { // offset
1826 uint16_t o = ntohs(*(uint16_t *) p);
1827 p += o + 2;
1828 }
1829 if ((p - buf) > l)
1830 {
1831 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1832 STAT(tunnel_rx_errors);
1833 return;
1834 }
1835 l -= (p - buf);
1836 if (*buf & 0x80)
1837 { // control
1838 uint16_t message = 0xFFFF; // message type
1839 uint8_t fatal = 0;
1840 uint8_t mandatory = 0;
1841 uint8_t authtype = 0; // proxy auth type
1842 uint16_t asession = 0; // assigned session
1843 uint32_t amagic = 0; // magic number
1844 uint8_t aflags = 0; // flags from last LCF
1845 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1846 char called[MAXTEL] = ""; // called number
1847 char calling[MAXTEL] = ""; // calling number
1848
1849 if (!config->cluster_iam_master)
1850 {
1851 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1852 return;
1853 }
1854
1855 // control messages must have bits 0x80|0x40|0x08
1856 // (type, length and sequence) set, and bits 0x02|0x01
1857 // (offset and priority) clear
1858 if ((*buf & 0xCB) != 0xC8)
1859 {
1860 LOG(1, s, t, "Bad control header %02X\n", *buf);
1861 STAT(tunnel_rx_errors);
1862 return;
1863 }
1864
1865 // check for duplicate tunnel open message
1866 if (!t && ns == 0)
1867 {
1868 int i;
1869
1870 //
1871 // Is this a duplicate of the first packet? (SCCRQ)
1872 //
1873 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1874 {
1875 if (tunnel[i].state != TUNNELOPENING ||
1876 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1877 tunnel[i].port != ntohs(addr->sin_port) )
1878 continue;
1879 t = i;
1880 LOG(3, s, t, "Duplicate SCCRQ?\n");
1881 break;
1882 }
1883 }
1884
1885 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1886 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1887
1888 // if no tunnel specified, assign one
1889 if (!t)
1890 {
1891 if (!(t = new_tunnel()))
1892 {
1893 LOG(1, 0, 0, "No more tunnels\n");
1894 STAT(tunnel_overflow);
1895 return;
1896 }
1897 tunnelclear(t);
1898 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1899 tunnel[t].port = ntohs(addr->sin_port);
1900 tunnel[t].window = 4; // default window
1901 STAT(tunnel_created);
1902 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1903 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1904 }
1905
1906 // If the 'ns' just received is not the 'nr' we're
1907 // expecting, just send an ack and drop it.
1908 //
1909 // if 'ns' is less, then we got a retransmitted packet.
1910 // if 'ns' is greater than missed a packet. Either way
1911 // we should ignore it.
1912 if (ns != tunnel[t].nr)
1913 {
1914 // is this the sequence we were expecting?
1915 STAT(tunnel_rx_errors);
1916 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1917 t, ns, tunnel[t].nr);
1918
1919 if (l) // Is this not a ZLB?
1920 controlnull(t);
1921 return;
1922 }
1923
1924 // This is used to time out old tunnels
1925 tunnel[t].lastrec = time_now;
1926
1927 // check sequence of this message
1928 {
1929 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1930 // some to clear maybe?
1931 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1932 {
1933 controlt *c = tunnel[t].controls;
1934 tunnel[t].controls = c->next;
1935 tunnel[t].controlc--;
1936 c->next = controlfree;
1937 controlfree = c;
1938 skip--;
1939 tunnel[t].try = 0; // we have progress
1940 }
1941
1942 // receiver advance (do here so quoted correctly in any sends below)
1943 if (l) tunnel[t].nr = (ns + 1);
1944 if (skip < 0) skip = 0;
1945 if (skip < tunnel[t].controlc)
1946 {
1947 // some control packets can now be sent that were previous stuck out of window
1948 int tosend = tunnel[t].window - skip;
1949 controlt *c = tunnel[t].controls;
1950 while (c && skip)
1951 {
1952 c = c->next;
1953 skip--;
1954 }
1955 while (c && tosend)
1956 {
1957 tunnel[t].try = 0; // first send
1958 tunnelsend(c->buf, c->length, t);
1959 c = c->next;
1960 tosend--;
1961 }
1962 }
1963 if (!tunnel[t].controlc)
1964 tunnel[t].retry = 0; // caught up
1965 }
1966 if (l)
1967 { // if not a null message
1968 int result = 0;
1969 int error = 0;
1970 char *msg = 0;
1971
1972 // process AVPs
1973 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1974 {
1975 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1976 uint8_t *b = p;
1977 uint8_t flags = *p;
1978 uint16_t mtype;
1979 if (n > l)
1980 {
1981 LOG(1, s, t, "Invalid length in AVP\n");
1982 STAT(tunnel_rx_errors);
1983 return;
1984 }
1985 p += n; // next
1986 l -= n;
1987 if (flags & 0x3C) // reserved bits, should be clear
1988 {
1989 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1990 fatal = flags;
1991 result = 2; // general error
1992 error = 3; // reserved field non-zero
1993 msg = 0;
1994 continue; // next
1995 }
1996 b += 2;
1997 if (*(uint16_t *) (b))
1998 {
1999 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
2000 fatal = flags;
2001 result = 2; // general error
2002 error = 6; // generic vendor-specific error
2003 msg = "unsupported vendor-specific";
2004 continue; // next
2005 }
2006 b += 2;
2007 mtype = ntohs(*(uint16_t *) (b));
2008 b += 2;
2009 n -= 6;
2010
2011 if (flags & 0x40)
2012 {
2013 uint16_t orig_len;
2014
2015 // handle hidden AVPs
2016 if (!*config->l2tpsecret)
2017 {
2018 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2019 fatal = flags;
2020 result = 2; // general error
2021 error = 6; // generic vendor-specific error
2022 msg = "secret not specified";
2023 continue;
2024 }
2025 if (!session[s].random_vector_length)
2026 {
2027 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2028 fatal = flags;
2029 result = 2; // general error
2030 error = 6; // generic
2031 msg = "no random vector";
2032 continue;
2033 }
2034 if (n < 8)
2035 {
2036 LOG(2, s, t, "Short hidden AVP.\n");
2037 fatal = flags;
2038 result = 2; // general error
2039 error = 2; // length is wrong
2040 msg = 0;
2041 continue;
2042 }
2043
2044 // Unhide the AVP
2045 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2046
2047 orig_len = ntohs(*(uint16_t *) b);
2048 if (orig_len > n + 2)
2049 {
2050 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2051 orig_len, n);
2052
2053 fatal = flags;
2054 result = 2; // general error
2055 error = 2; // length is wrong
2056 msg = 0;
2057 continue;
2058 }
2059
2060 b += 2;
2061 n = orig_len;
2062 }
2063
2064 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, avp_name(mtype), n,
2065 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2066
2067 switch (mtype)
2068 {
2069 case 0: // message type
2070 message = ntohs(*(uint16_t *) b);
2071 mandatory = flags & 0x80;
2072 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_type(message));
2073 break;
2074 case 1: // result code
2075 {
2076 uint16_t rescode = ntohs(*(uint16_t *) b);
2077 const char* resdesc = "(unknown)";
2078 if (message == 4)
2079 { /* StopCCN */
2080 resdesc = stopccn_result_code(rescode);
2081 }
2082 else if (message == 14)
2083 { /* CDN */
2084 resdesc = cdn_result_code(rescode);
2085 }
2086
2087 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2088 if (n >= 4)
2089 {
2090 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2091 LOG(4, s, t, " Error Code %d: %s\n", errcode, error_code(errcode));
2092 }
2093 if (n > 4)
2094 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2095
2096 break;
2097 }
2098 break;
2099 case 2: // protocol version
2100 {
2101 version = ntohs(*(uint16_t *) (b));
2102 LOG(4, s, t, " Protocol version = %d\n", version);
2103 if (version && version != 0x0100)
2104 { // allow 0.0 and 1.0
2105 LOG(1, s, t, " Bad protocol version %04X\n", version);
2106 fatal = flags;
2107 result = 5; // unspported protocol version
2108 error = 0x0100; // supported version
2109 msg = 0;
2110 continue; // next
2111 }
2112 }
2113 break;
2114 case 3: // framing capabilities
2115 // LOG(4, s, t, "Framing capabilities\n");
2116 break;
2117 case 4: // bearer capabilities
2118 // LOG(4, s, t, "Bearer capabilities\n");
2119 break;
2120 case 5: // tie breaker
2121 // We never open tunnels, so we don't care about tie breakers
2122 // LOG(4, s, t, "Tie breaker\n");
2123 continue;
2124 case 6: // firmware revision
2125 // LOG(4, s, t, "Firmware revision\n");
2126 break;
2127 case 7: // host name
2128 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2129 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2130 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2131 // TBA - to send to RADIUS
2132 break;
2133 case 8: // vendor name
2134 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2135 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2136 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2137 break;
2138 case 9: // assigned tunnel
2139 tunnel[t].far = ntohs(*(uint16_t *) (b));
2140 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2141 break;
2142 case 10: // rx window
2143 tunnel[t].window = ntohs(*(uint16_t *) (b));
2144 if (!tunnel[t].window)
2145 tunnel[t].window = 1; // window of 0 is silly
2146 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2147 break;
2148 case 11: // Challenge
2149 {
2150 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2151 build_chap_response(b, 2, n, &chapresponse);
2152 }
2153 break;
2154 case 13: // Response
2155 // Why did they send a response? We never challenge.
2156 LOG(2, s, t, " received unexpected challenge response\n");
2157 break;
2158
2159 case 14: // assigned session
2160 asession = session[s].far = ntohs(*(uint16_t *) (b));
2161 LOG(4, s, t, " assigned session = %d\n", asession);
2162 break;
2163 case 15: // call serial number
2164 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2165 break;
2166 case 18: // bearer type
2167 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2168 // TBA - for RADIUS
2169 break;
2170 case 19: // framing type
2171 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2172 // TBA
2173 break;
2174 case 21: // called number
2175 memset(called, 0, sizeof(called));
2176 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2177 LOG(4, s, t, " Called <%s>\n", called);
2178 break;
2179 case 22: // calling number
2180 memset(calling, 0, sizeof(calling));
2181 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2182 LOG(4, s, t, " Calling <%s>\n", calling);
2183 break;
2184 case 23: // subtype
2185 break;
2186 case 24: // tx connect speed
2187 if (n == 4)
2188 {
2189 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2190 }
2191 else
2192 {
2193 // AS5300s send connect speed as a string
2194 char tmp[30];
2195 memset(tmp, 0, sizeof(tmp));
2196 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2197 session[s].tx_connect_speed = atol(tmp);
2198 }
2199 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2200 break;
2201 case 38: // rx connect speed
2202 if (n == 4)
2203 {
2204 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2205 }
2206 else
2207 {
2208 // AS5300s send connect speed as a string
2209 char tmp[30];
2210 memset(tmp, 0, sizeof(tmp));
2211 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2212 session[s].rx_connect_speed = atol(tmp);
2213 }
2214 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2215 break;
2216 case 25: // Physical Channel ID
2217 {
2218 uint32_t tmp = ntohl(*(uint32_t *) b);
2219 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2220 break;
2221 }
2222 case 29: // Proxy Authentication Type
2223 {
2224 uint16_t atype = ntohs(*(uint16_t *)b);
2225 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
2226 if (atype == 2)
2227 authtype = AUTHCHAP;
2228 else if (atype == 3)
2229 authtype = AUTHPAP;
2230
2231 break;
2232 }
2233 case 30: // Proxy Authentication Name
2234 {
2235 char authname[64];
2236 memset(authname, 0, sizeof(authname));
2237 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2238 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2239 authname);
2240 break;
2241 }
2242 case 31: // Proxy Authentication Challenge
2243 {
2244 LOG(4, s, t, " Proxy Auth Challenge\n");
2245 if (sess_local[s].radius)
2246 memcpy(radius[sess_local[s].radius].auth, b, 16);
2247 break;
2248 }
2249 case 32: // Proxy Authentication ID
2250 {
2251 uint16_t authid = ntohs(*(uint16_t *)(b));
2252 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2253 if (sess_local[s].radius)
2254 radius[sess_local[s].radius].id = authid;
2255 break;
2256 }
2257 case 33: // Proxy Authentication Response
2258 LOG(4, s, t, " Proxy Auth Response\n");
2259 break;
2260 case 27: // last sent lcp
2261 { // find magic number
2262 uint8_t *p = b, *e = p + n;
2263 while (p + 1 < e && p[1] && p + p[1] <= e)
2264 {
2265 if (*p == 5 && p[1] == 6) // Magic-Number
2266 amagic = ntohl(*(uint32_t *) (p + 2));
2267 else if (*p == 3 && p[1] == 4 && *(uint16_t *) (p + 2) == htons(PPPPAP)) // Authentication-Protocol (PAP)
2268 authtype = AUTHPAP;
2269 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol (CHAP)
2270 authtype = AUTHCHAP;
2271 else if (*p == 7) // Protocol-Field-Compression
2272 aflags |= SESSIONPFC;
2273 else if (*p == 8) // Address-and-Control-Field-Compression
2274 aflags |= SESSIONACFC;
2275 p += p[1];
2276 }
2277 }
2278 break;
2279 case 28: // last recv lcp confreq
2280 break;
2281 case 26: // Initial Received LCP CONFREQ
2282 break;
2283 case 39: // seq required - we control it as an LNS anyway...
2284 break;
2285 case 36: // Random Vector
2286 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2287 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2288 if (n > sizeof(session[s].random_vector))
2289 n = sizeof(session[s].random_vector);
2290 memcpy(session[s].random_vector, b, n);
2291 session[s].random_vector_length = n;
2292 break;
2293 default:
2294 {
2295 static char e[] = "unknown AVP 0xXXXX";
2296 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2297 fatal = flags;
2298 result = 2; // general error
2299 error = 8; // unknown mandatory AVP
2300 sprintf((msg = e) + 14, "%04x", mtype);
2301 continue; // next
2302 }
2303 }
2304 }
2305 // process message
2306 if (fatal & 0x80)
2307 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2308 else
2309 switch (message)
2310 {
2311 case 1: // SCCRQ - Start Control Connection Request
2312 tunnel[t].state = TUNNELOPENING;
2313 if (main_quit != QUIT_SHUTDOWN)
2314 {
2315 controlt *c = controlnew(2); // sending SCCRP
2316 control16(c, 2, version, 1); // protocol version
2317 control32(c, 3, 3, 1); // framing
2318 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2319 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2320 control16(c, 9, t, 1); // assigned tunnel
2321 controladd(c, t, 0); // send the resply
2322 }
2323 else
2324 {
2325 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2326 }
2327 break;
2328 case 2: // SCCRP
2329 tunnel[t].state = TUNNELOPEN;
2330 break;
2331 case 3: // SCCN
2332 tunnel[t].state = TUNNELOPEN;
2333 controlnull(t); // ack
2334 break;
2335 case 4: // StopCCN
2336 controlnull(t); // ack
2337 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2338 break;
2339 case 6: // HELLO
2340 controlnull(t); // simply ACK
2341 break;
2342 case 7: // OCRQ
2343 // TBA
2344 break;
2345 case 8: // OCRO
2346 // TBA
2347 break;
2348 case 9: // OCCN
2349 // TBA
2350 break;
2351 case 10: // ICRQ
2352 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2353 {
2354 uint16_t r;
2355
2356 s = sessionfree;
2357 sessionfree = session[s].next;
2358 memset(&session[s], 0, sizeof(session[s]));
2359
2360 if (s > config->cluster_highest_sessionid)
2361 config->cluster_highest_sessionid = s;
2362
2363 // make a RADIUS session
2364 if ((r = radiusnew(s)))
2365 {
2366 controlt *c = controlnew(11); // sending ICRP
2367 session[s].opened = time_now;
2368 session[s].tunnel = t;
2369 session[s].far = asession;
2370 session[s].last_packet = time_now;
2371 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2372 control16(c, 14, s, 1); // assigned session
2373 controladd(c, t, asession); // send the reply
2374
2375 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
2376 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2377 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2378 STAT(session_created);
2379 break;
2380 }
2381
2382
2383 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
2384 sessionclear(s);
2385 }
2386 else
2387 {
2388 STAT(session_overflow);
2389 LOG(1, 0, t, "No free sessions\n");
2390 }
2391
2392 {
2393 controlt *c = controlnew(14); // CDN
2394 if (main_quit == QUIT_SHUTDOWN)
2395 control16(c, 1, 2, 7); // try another
2396 else
2397 control16(c, 1, 4, 0); // temporary lack of resources
2398
2399 controladd(c, t, asession); // send the message
2400 }
2401 return;
2402 case 11: // ICRP
2403 // TBA
2404 break;
2405 case 12: // ICCN
2406 if (amagic == 0) amagic = time_now;
2407 session[s].magic = amagic; // set magic number
2408 session[s].l2tp_flags = aflags; // set flags received
2409 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
2410 controlnull(t); // ack
2411 // proxy authentication type is not supported
2412 if (!(config->radius_authtypes & authtype))
2413 authtype = config->radius_authprefer;
2414
2415 // start LCP
2416 sendlcp(t, s, authtype);
2417 break;
2418 case 14: // CDN
2419 controlnull(t); // ack
2420 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2421 break;
2422 case 0xFFFF:
2423 LOG(1, s, t, "Missing message type\n");
2424 break;
2425 default:
2426 STAT(tunnel_rx_errors);
2427 if (mandatory)
2428 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2429 else
2430 LOG(1, s, t, "Unknown message type %d\n", message);
2431 break;
2432 }
2433 if (chapresponse) free(chapresponse);
2434 cluster_send_tunnel(t);
2435 }
2436 else
2437 {
2438 LOG(4, s, t, " Got a ZLB ack\n");
2439 }
2440 }
2441 else
2442 { // data
2443 uint16_t prot;
2444
2445 LOG_HEX(5, "Receive Tunnel Data", p, l);
2446 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2447 { // HDLC address header, discard
2448 p += 2;
2449 l -= 2;
2450 }
2451 if (l < 2)
2452 {
2453 LOG(1, s, t, "Short ppp length %d\n", l);
2454 STAT(tunnel_rx_errors);
2455 return;
2456 }
2457 if (*p & 1)
2458 {
2459 prot = *p++;
2460 l--;
2461 }
2462 else
2463 {
2464 prot = ntohs(*(uint16_t *) p);
2465 p += 2;
2466 l -= 2;
2467 }
2468
2469 if (s && !session[s].opened) // Is something wrong??
2470 {
2471 if (!config->cluster_iam_master)
2472 {
2473 // Pass it off to the master to deal with..
2474 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2475 return;
2476 }
2477
2478
2479 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2480 STAT(tunnel_rx_errors);
2481 return;
2482 }
2483
2484 if (prot == PPPPAP)
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 processpap(t, s, p, l);
2489 }
2490 else if (prot == PPPCHAP)
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 processchap(t, s, p, l);
2495 }
2496 else if (prot == PPPLCP)
2497 {
2498 session[s].last_packet = time_now;
2499 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2500 processlcp(t, s, p, l);
2501 }
2502 else if (prot == PPPIPCP)
2503 {
2504 session[s].last_packet = time_now;
2505 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2506 processipcp(t, s, p, l);
2507 }
2508 else if (prot == PPPIPV6CP)
2509 {
2510 if (config->ipv6_prefix.s6_addr[0] > 0)
2511 {
2512 session[s].last_packet = time_now;
2513 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2514 processipv6cp(t, s, p, l);
2515 }
2516 else
2517 {
2518 LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
2519 }
2520 }
2521 else if (prot == PPPCCP)
2522 {
2523 session[s].last_packet = time_now;
2524 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2525 processccp(t, s, p, l);
2526 }
2527 else if (prot == PPPIP)
2528 {
2529 if (session[s].die)
2530 {
2531 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2532 return; // closing session, PPP not processed
2533 }
2534
2535 session[s].last_packet = time_now;
2536 if (session[s].walled_garden && !config->cluster_iam_master)
2537 {
2538 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2539 return;
2540 }
2541
2542 processipin(t, s, p, l);
2543 }
2544 else if (prot == PPPIPV6)
2545 {
2546 if (!config->ipv6_prefix.s6_addr[0] > 0)
2547 {
2548 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2549 return;
2550 }
2551 if (session[s].die)
2552 {
2553 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2554 return; // closing session, PPP not processed
2555 }
2556
2557 session[s].last_packet = time_now;
2558 if (session[s].walled_garden && !config->cluster_iam_master)
2559 {
2560 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2561 return;
2562 }
2563
2564 processipv6in(t, s, p, l);
2565 }
2566 else
2567 {
2568 STAT(tunnel_rx_errors);
2569 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2570 }
2571 }
2572 }
2573
2574 // read and process packet on tun
2575 static void processtun(uint8_t * buf, int len)
2576 {
2577 LOG_HEX(5, "Receive TUN Data", buf, len);
2578 STAT(tun_rx_packets);
2579 INC_STAT(tun_rx_bytes, len);
2580
2581 CSTAT(processtun);
2582
2583 eth_rx_pkt++;
2584 eth_rx += len;
2585 if (len < 22)
2586 {
2587 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2588 STAT(tun_rx_errors);
2589 return;
2590 }
2591
2592 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2593 processipout(buf, len);
2594 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2595 && config->ipv6_prefix.s6_addr[0] > 0)
2596 processipv6out(buf, len);
2597
2598 // Else discard.
2599 }
2600
2601 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2602 // that we look at the whole of the tunnel, radius and session tables
2603 // every second
2604 static void regular_cleanups(double period)
2605 {
2606 // Next tunnel, radius and session to check for actions on.
2607 static tunnelidt t = 0;
2608 static int r = 0;
2609 static sessionidt s = 0;
2610
2611 int t_actions = 0;
2612 int r_actions = 0;
2613 int s_actions = 0;
2614
2615 int t_slice;
2616 int r_slice;
2617 int s_slice;
2618
2619 int i;
2620 int a;
2621
2622 // divide up tables into slices based on the last run
2623 t_slice = config->cluster_highest_tunnelid * period;
2624 r_slice = (MAXRADIUS - 1) * period;
2625 s_slice = config->cluster_highest_sessionid * period;
2626
2627 if (t_slice < 1)
2628 t_slice = 1;
2629 else if (t_slice > config->cluster_highest_tunnelid)
2630 t_slice = config->cluster_highest_tunnelid;
2631
2632 if (r_slice < 1)
2633 r_slice = 1;
2634 else if (r_slice > (MAXRADIUS - 1))
2635 r_slice = MAXRADIUS - 1;
2636
2637 if (s_slice < 1)
2638 s_slice = 1;
2639 else if (s_slice > config->cluster_highest_sessionid)
2640 s_slice = config->cluster_highest_sessionid;
2641
2642 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2643
2644 for (i = 0; i < t_slice; i++)
2645 {
2646 t++;
2647 if (t > config->cluster_highest_tunnelid)
2648 t = 1;
2649
2650 // check for expired tunnels
2651 if (tunnel[t].die && tunnel[t].die <= TIME)
2652 {
2653 STAT(tunnel_timeout);
2654 tunnelkill(t, "Expired");
2655 t_actions++;
2656 continue;
2657 }
2658 // check for message resend
2659 if (tunnel[t].retry && tunnel[t].controlc)
2660 {
2661 // resend pending messages as timeout on reply
2662 if (tunnel[t].retry <= TIME)
2663 {
2664 controlt *c = tunnel[t].controls;
2665 uint8_t w = tunnel[t].window;
2666 tunnel[t].try++; // another try
2667 if (tunnel[t].try > 5)
2668 tunnelkill(t, "Timeout on control message"); // game over
2669 else
2670 while (c && w--)
2671 {
2672 tunnelsend(c->buf, c->length, t);
2673 c = c->next;
2674 }
2675
2676 t_actions++;
2677 }
2678 }
2679 // Send hello
2680 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2681 {
2682 controlt *c = controlnew(6); // sending HELLO
2683 controladd(c, t, 0); // send the message
2684 LOG(3, 0, t, "Sending HELLO message\n");
2685 t_actions++;
2686 }
2687
2688 // Check for tunnel changes requested from the CLI
2689 if ((a = cli_tunnel_actions[t].action))
2690 {
2691 cli_tunnel_actions[t].action = 0;
2692 if (a & CLI_TUN_KILL)
2693 {
2694 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2695 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2696 t_actions++;
2697 }
2698 }
2699 }
2700
2701 for (i = 0; i < r_slice; i++)
2702 {
2703 r++;
2704 if (r >= MAXRADIUS)
2705 r = 1;
2706
2707 if (!radius[r].state)
2708 continue;
2709
2710 if (radius[r].retry <= TIME)
2711 {
2712 radiusretry(r);
2713 r_actions++;
2714 }
2715 }
2716
2717 for (i = 0; i < s_slice; i++)
2718 {
2719 s++;
2720 if (s > config->cluster_highest_sessionid)
2721 s = 1;
2722
2723 if (!session[s].opened) // Session isn't in use
2724 continue;
2725
2726 // check for expired sessions
2727 if (session[s].die)
2728 {
2729 if (session[s].die <= TIME)
2730 {
2731 sessionkill(s, "Expired");
2732 s_actions++;
2733 }
2734 continue;
2735 }
2736
2737 if (session[s].ip && !(session[s].flags & SF_IPCP_ACKED)
2738 && !(sess_local[s].radius && radius[sess_local[s].radius].state == RADIUSIPCP))
2739 {
2740 // IPCP has not completed yet. Resend
2741 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2742 sendipcp(session[s].tunnel, s);
2743 s_actions++;
2744 }
2745
2746 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2747 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2748 {
2749 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2750 STAT(session_timeout);
2751 s_actions++;
2752 continue;
2753 }
2754
2755 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2756 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2757 {
2758 uint8_t b[MAXCONTROL] = {0};
2759
2760 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2761 if (!q) continue;
2762
2763 *q = EchoReq;
2764 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2765 *(uint16_t *)(q + 2) = htons(8); // Length
2766 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2767
2768 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2769 (int)(time_now - session[s].last_packet));
2770 tunnelsend(b, 24, session[s].tunnel); // send it
2771 s_actions++;
2772 }
2773
2774 // Check for actions requested from the CLI
2775 if ((a = cli_session_actions[s].action))
2776 {
2777 int send = 0;
2778
2779 cli_session_actions[s].action = 0;
2780 if (a & CLI_SESS_KILL)
2781 {
2782 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2783 sessionshutdown(s, "Requested by administrator.", 3, 0);
2784 a = 0; // dead, no need to check for other actions
2785 s_actions++;
2786 }
2787
2788 if (a & CLI_SESS_NOSNOOP)
2789 {
2790 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2791 session[s].snoop_ip = 0;
2792 session[s].snoop_port = 0;
2793 s_actions++;
2794 send++;
2795 }
2796 else if (a & CLI_SESS_SNOOP)
2797 {
2798 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2799 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2800 cli_session_actions[s].snoop_port);
2801
2802 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2803 session[s].snoop_port = cli_session_actions[s].snoop_port;
2804 s_actions++;
2805 send++;
2806 }
2807
2808 if (a & CLI_SESS_NOTHROTTLE)
2809 {
2810 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2811 throttle_session(s, 0, 0);
2812 s_actions++;
2813 send++;
2814 }
2815 else if (a & CLI_SESS_THROTTLE)
2816 {
2817 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2818 cli_session_actions[s].throttle_in,
2819 cli_session_actions[s].throttle_out);
2820
2821 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2822 s_actions++;
2823 send++;
2824 }
2825
2826 if (a & CLI_SESS_NOFILTER)
2827 {
2828 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2829 filter_session(s, 0, 0);
2830 s_actions++;
2831 send++;
2832 }
2833 else if (a & CLI_SESS_FILTER)
2834 {
2835 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2836 cli_session_actions[s].filter_in,
2837 cli_session_actions[s].filter_out);
2838
2839 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2840 s_actions++;
2841 send++;
2842 }
2843
2844 if (send)
2845 cluster_send_session(s);
2846 }
2847
2848 // RADIUS interim accounting
2849 if (config->radius_accounting && config->radius_interim > 0
2850 && session[s].ip && !session[s].walled_garden
2851 && !sess_local[s].radius // RADIUS already in progress
2852 && time_now - sess_local[s].last_interim >= config->radius_interim)
2853 {
2854 int rad = radiusnew(s);
2855 if (!rad)
2856 {
2857 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2858 STAT(radius_overflow);
2859 continue;
2860 }
2861
2862 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2863 session[s].user, session[s].unique_id);
2864
2865 radiussend(rad, RADIUSINTERIM);
2866 sess_local[s].last_interim = time_now;
2867 s_actions++;
2868 }
2869 }
2870
2871 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2872 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2873 }
2874
2875 //
2876 // Are we in the middle of a tunnel update, or radius
2877 // requests??
2878 //
2879 static int still_busy(void)
2880 {
2881 int i;
2882 static clockt last_talked = 0;
2883 static clockt start_busy_wait = 0;
2884
2885 if (!config->cluster_iam_master)
2886 {
2887 #ifdef BGP
2888 static time_t stopped_bgp = 0;
2889 if (bgp_configured)
2890 {
2891 if (!stopped_bgp)
2892 {
2893 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2894
2895 for (i = 0; i < BGP_NUM_PEERS; i++)
2896 if (bgp_peers[i].state == Established)
2897 bgp_stop(&bgp_peers[i]);
2898
2899 stopped_bgp = time_now;
2900
2901 // we don't want to become master
2902 cluster_send_ping(0);
2903
2904 return 1;
2905 }
2906
2907 if (time_now < (stopped_bgp + QUIT_DELAY))
2908 return 1;
2909 }
2910 #endif /* BGP */
2911
2912 return 0;
2913 }
2914
2915 if (main_quit == QUIT_SHUTDOWN)
2916 {
2917 static int dropped = 0;
2918 if (!dropped)
2919 {
2920 int i;
2921
2922 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
2923 for (i = 1; i < MAXTUNNEL; i++)
2924 if (tunnel[i].ip || tunnel[i].state)
2925 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
2926
2927 dropped = 1;
2928 }
2929 }
2930
2931 if (start_busy_wait == 0)
2932 start_busy_wait = TIME;
2933
2934 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2935 {
2936 if (!tunnel[i].controlc)
2937 continue;
2938
2939 if (last_talked != TIME)
2940 {
2941 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2942 last_talked = TIME;
2943 }
2944 return 1;
2945 }
2946
2947 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2948 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2949 {
2950 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2951 return 0;
2952 }
2953
2954 for (i = 1; i < MAXRADIUS; i++)
2955 {
2956 if (radius[i].state == RADIUSNULL)
2957 continue;
2958 if (radius[i].state == RADIUSWAIT)
2959 continue;
2960
2961 if (last_talked != TIME)
2962 {
2963 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2964 last_talked = TIME;
2965 }
2966 return 1;
2967 }
2968
2969 return 0;
2970 }
2971
2972 #ifdef HAVE_EPOLL
2973 # include <sys/epoll.h>
2974 #else
2975 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
2976 # include "fake_epoll.h"
2977 #endif
2978
2979 // the base set of fds polled: cli, cluster, tun, udp, control, dae
2980 #define BASE_FDS 6
2981
2982 // additional polled fds
2983 #ifdef BGP
2984 # define EXTRA_FDS BGP_NUM_PEERS
2985 #else
2986 # define EXTRA_FDS 0
2987 #endif
2988
2989 // main loop - gets packets on tun or udp and processes them
2990 static void mainloop(void)
2991 {
2992 int i;
2993 uint8_t buf[65536];
2994 clockt next_cluster_ping = 0; // send initial ping immediately
2995 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
2996 int maxevent = sizeof(events)/sizeof(*events);
2997
2998 if ((epollfd = epoll_create(maxevent)) < 0)
2999 {
3000 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3001 exit(1);
3002 }
3003
3004 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3005 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3006
3007 /* setup our fds to poll for input */
3008 {
3009 static struct event_data d[BASE_FDS];
3010 struct epoll_event e;
3011
3012 e.events = EPOLLIN;
3013 i = 0;
3014
3015 d[i].type = FD_TYPE_CLI;
3016 e.data.ptr = &d[i++];
3017 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3018
3019 d[i].type = FD_TYPE_CLUSTER;
3020 e.data.ptr = &d[i++];
3021 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3022
3023 d[i].type = FD_TYPE_TUN;
3024 e.data.ptr = &d[i++];
3025 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3026
3027 d[i].type = FD_TYPE_UDP;
3028 e.data.ptr = &d[i++];
3029 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3030
3031 d[i].type = FD_TYPE_CONTROL;
3032 e.data.ptr = &d[i++];
3033 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3034
3035 d[i].type = FD_TYPE_DAE;
3036 e.data.ptr = &d[i++];
3037 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3038 }
3039
3040 #ifdef BGP
3041 signal(SIGPIPE, SIG_IGN);
3042 bgp_setup(config->as_number);
3043 if (config->bind_address)
3044 bgp_add_route(config->bind_address, 0xffffffff);
3045
3046 for (i = 0; i < BGP_NUM_PEERS; i++)
3047 {
3048 if (config->neighbour[i].name[0])
3049 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3050 config->neighbour[i].as, config->neighbour[i].keepalive,
3051 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3052 }
3053 #endif /* BGP */
3054
3055 while (!main_quit || still_busy())
3056 {
3057 int more = 0;
3058 int n;
3059
3060 if (config->reload_config)
3061 {
3062 // Update the config state based on config settings
3063 update_config();
3064 }
3065
3066 #ifdef BGP
3067 bgp_set_poll();
3068 #endif /* BGP */
3069
3070 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3071 STAT(select_called);
3072
3073 TIME = now(NULL);
3074 if (n < 0)
3075 {
3076 if (errno == EINTR ||
3077 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3078 continue;
3079
3080 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3081 break; // exit
3082 }
3083
3084 if (n)
3085 {
3086 struct sockaddr_in addr;
3087 int alen, c, s;
3088 int udp_ready = 0;
3089 int tun_ready = 0;
3090 int cluster_ready = 0;
3091 int udp_pkts = 0;
3092 int tun_pkts = 0;
3093 int cluster_pkts = 0;
3094 #ifdef BGP
3095 uint32_t bgp_events[BGP_NUM_PEERS];
3096 memset(bgp_events, 0, sizeof(bgp_events));
3097 #endif /* BGP */
3098
3099 for (c = n, i = 0; i < c; i++)
3100 {
3101 struct event_data *d = events[i].data.ptr;
3102 switch (d->type)
3103 {
3104 case FD_TYPE_CLI: // CLI connections
3105 {
3106 int cli;
3107
3108 alen = sizeof(addr);
3109 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3110 {
3111 cli_do(cli);
3112 close(cli);
3113 }
3114 else
3115 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3116
3117 n--;
3118 break;
3119 }
3120
3121 // these are handled below, with multiple interleaved reads
3122 case FD_TYPE_CLUSTER: cluster_ready++; break;
3123 case FD_TYPE_TUN: tun_ready++; break;
3124 case FD_TYPE_UDP: udp_ready++; break;
3125
3126 case FD_TYPE_CONTROL: // nsctl commands
3127 alen = sizeof(addr);
3128 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3129 n--;
3130 break;
3131
3132 case FD_TYPE_DAE: // DAE requests
3133 alen = sizeof(addr);
3134 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3135 n--;
3136 break;
3137
3138 case FD_TYPE_RADIUS: // RADIUS response
3139 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3140 if (s >= 0 && config->cluster_iam_master)
3141 processrad(buf, s, d->index);
3142
3143 n--;
3144 break;
3145
3146 #ifdef BGP
3147 case FD_TYPE_BGP:
3148 bgp_events[d->index] = events[i].events;
3149 n--;
3150 break;
3151 #endif /* BGP */
3152
3153 default:
3154 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3155 }
3156 }
3157
3158 #ifdef BGP
3159 bgp_process(bgp_events);
3160 #endif /* BGP */
3161
3162 for (c = 0; n && c < config->multi_read_count; c++)
3163 {
3164 // L2TP
3165 if (udp_ready)
3166 {
3167 alen = sizeof(addr);
3168 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3169 {
3170 processudp(buf, s, &addr);
3171 udp_pkts++;
3172 }
3173 else
3174 {
3175 udp_ready = 0;
3176 n--;
3177 }
3178 }
3179
3180 // incoming IP
3181 if (tun_ready)
3182 {
3183 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3184 {
3185 processtun(buf, s);
3186 tun_pkts++;
3187 }
3188 else
3189 {
3190 tun_ready = 0;
3191 n--;
3192 }
3193 }
3194
3195 // cluster
3196 if (cluster_ready)
3197 {
3198 alen = sizeof(addr);
3199 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3200 {
3201 processcluster(buf, s, addr.sin_addr.s_addr);
3202 cluster_pkts++;
3203 }
3204 else
3205 {
3206 cluster_ready = 0;
3207 n--;
3208 }
3209 }
3210 }
3211
3212 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3213 STAT(multi_read_used);
3214
3215 if (c >= config->multi_read_count)
3216 {
3217 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3218 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3219
3220 STAT(multi_read_exceeded);
3221 more++;
3222 }
3223 }
3224
3225 // Runs on every machine (master and slaves).
3226 if (next_cluster_ping <= TIME)
3227 {
3228 // Check to see which of the cluster is still alive..
3229
3230 cluster_send_ping(basetime); // Only does anything if we're a slave
3231 cluster_check_master(); // ditto.
3232
3233 cluster_heartbeat(); // Only does anything if we're a master.
3234 cluster_check_slaves(); // ditto.
3235
3236 master_update_counts(); // If we're a slave, send our byte counters to our master.
3237
3238 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3239 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3240 else
3241 next_cluster_ping = TIME + config->cluster_hb_interval;
3242 }
3243
3244 if (!config->cluster_iam_master)
3245 continue;
3246
3247 // Run token bucket filtering queue..
3248 // Only run it every 1/10th of a second.
3249 {
3250 static clockt last_run = 0;
3251 if (last_run != TIME)
3252 {
3253 last_run = TIME;
3254 tbf_run_timer();
3255 }
3256 }
3257
3258 // Handle timeouts, retries etc.
3259 {
3260 static double last_clean = 0;
3261 double this_clean;
3262 double diff;
3263
3264 TIME = now(&this_clean);
3265 diff = this_clean - last_clean;
3266
3267 // Run during idle time (after we've handled
3268 // all incoming packets) or every 1/10th sec
3269 if (!more || diff > 0.1)
3270 {
3271 regular_cleanups(diff);
3272 last_clean = this_clean;
3273 }
3274 }
3275
3276 if (*config->accounting_dir)
3277 {
3278 static clockt next_acct = 0;
3279 static clockt next_shut_acct = 0;
3280
3281 if (next_acct <= TIME)
3282 {
3283 // Dump accounting data
3284 next_acct = TIME + ACCT_TIME;
3285 next_shut_acct = TIME + ACCT_SHUT_TIME;
3286 dump_acct_info(1);
3287 }
3288 else if (next_shut_acct <= TIME)
3289 {
3290 // Dump accounting data for shutdown sessions
3291 next_shut_acct = TIME + ACCT_SHUT_TIME;
3292 if (shut_acct_n)
3293 dump_acct_info(0);
3294 }
3295 }
3296 }
3297
3298 // Are we the master and shutting down??
3299 if (config->cluster_iam_master)
3300 cluster_heartbeat(); // Flush any queued changes..
3301
3302 // Ok. Notify everyone we're shutting down. If we're
3303 // the master, this will force an election.
3304 cluster_send_ping(0);
3305
3306 //
3307 // Important!!! We MUST not process any packets past this point!
3308 LOG(1, 0, 0, "Shutdown complete\n");
3309 }
3310
3311 static void stripdomain(char *host)
3312 {
3313 char *p;
3314
3315 if ((p = strchr(host, '.')))
3316 {
3317 char *domain = 0;
3318 char _domain[1024];
3319
3320 // strip off domain
3321 FILE *resolv = fopen("/etc/resolv.conf", "r");
3322 if (resolv)
3323 {
3324 char buf[1024];
3325 char *b;
3326
3327 while (fgets(buf, sizeof(buf), resolv))
3328 {
3329 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3330 continue;
3331
3332 if (!isspace(buf[6]))
3333 continue;
3334
3335 b = buf + 7;
3336 while (isspace(*b)) b++;
3337
3338 if (*b)
3339 {
3340 char *d = b;
3341 while (*b && !isspace(*b)) b++;
3342 *b = 0;
3343 if (buf[0] == 'd') // domain is canonical
3344 {
3345 domain = d;
3346 break;
3347 }
3348
3349 // first search line
3350 if (!domain)
3351 {
3352 // hold, may be subsequent domain line
3353 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3354 domain = _domain;
3355 }
3356 }
3357 }
3358
3359 fclose(resolv);
3360 }
3361
3362 if (domain)
3363 {
3364 int hl = strlen(host);
3365 int dl = strlen(domain);
3366 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3367 host[hl -dl - 1] = 0;
3368 }
3369 else
3370 {
3371 *p = 0; // everything after first dot
3372 }
3373 }
3374 }
3375
3376 // Init data structures
3377 static void initdata(int optdebug, char *optconfig)
3378 {
3379 int i;
3380
3381 if (!(config = shared_malloc(sizeof(configt))))
3382 {
3383 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3384 exit(1);
3385 }
3386
3387 memset(config, 0, sizeof(configt));
3388 time(&config->start_time);
3389 strncpy(config->config_file, optconfig, strlen(optconfig));
3390 config->debug = optdebug;
3391 config->num_tbfs = MAXTBFS;
3392 config->rl_rate = 28; // 28kbps
3393 config->cluster_master_min_adv = 1;
3394 strcpy(config->random_device, RANDOMDEVICE);
3395
3396 log_stream = stderr;
3397
3398 #ifdef RINGBUFFER
3399 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3400 {
3401 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3402 exit(1);
3403 }
3404 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3405 #endif
3406
3407 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3408 {
3409 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3410 exit(1);
3411 }
3412 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3413 {
3414 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3415 exit(1);
3416 }
3417 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3418 {
3419 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3420 exit(1);
3421 }
3422
3423 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3424 {
3425 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3426 exit(1);
3427 }
3428
3429 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3430 {
3431 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3432 exit(1);
3433 }
3434
3435 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3436 {
3437 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3438 exit(1);
3439 }
3440
3441 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3442 {
3443 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3444 exit(1);
3445 }
3446 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3447
3448 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3449 {
3450 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3451 exit(1);
3452 }
3453 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3454
3455 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3456 {
3457 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3458 exit(1);
3459 }
3460 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3461
3462 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3463 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3464 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3465 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3466
3467 // Put all the sessions on the free list marked as undefined.
3468 for (i = 1; i < MAXSESSION; i++)
3469 {
3470 session[i].next = i + 1;
3471 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3472 }
3473 session[MAXSESSION - 1].next = 0;
3474 sessionfree = 1;
3475
3476 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3477 for (i = 1; i < MAXTUNNEL; i++)
3478 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3479
3480 if (!*hostname)
3481 {
3482 // Grab my hostname unless it's been specified
3483 gethostname(hostname, sizeof(hostname));
3484 stripdomain(hostname);
3485 }
3486
3487 _statistics->start_time = _statistics->last_reset = time(NULL);
3488
3489 #ifdef BGP
3490 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3491 {
3492 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3493 exit(1);
3494 }
3495 #endif /* BGP */
3496 }
3497
3498 static int assign_ip_address(sessionidt s)
3499 {
3500 uint32_t i;
3501 int best = -1;
3502 time_t best_time = time_now;
3503 char *u = session[s].user;
3504 char reuse = 0;
3505
3506
3507 CSTAT(assign_ip_address);
3508
3509 for (i = 1; i < ip_pool_size; i++)
3510 {
3511 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3512 continue;
3513
3514 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3515 {
3516 best = i;
3517 reuse = 1;
3518 break;
3519 }
3520
3521 if (ip_address_pool[i].last < best_time)
3522 {
3523 best = i;
3524 if (!(best_time = ip_address_pool[i].last))
3525 break; // never used, grab this one
3526 }
3527 }
3528
3529 if (best < 0)
3530 {
3531 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3532 return 0;
3533 }
3534
3535 session[s].ip = ip_address_pool[best].address;
3536 session[s].ip_pool_index = best;
3537 ip_address_pool[best].assigned = 1;
3538 ip_address_pool[best].last = time_now;
3539 ip_address_pool[best].session = s;
3540 if (session[s].walled_garden)
3541 /* Don't track addresses of users in walled garden (note: this
3542 means that their address isn't "sticky" even if they get
3543 un-gardened). */
3544 ip_address_pool[best].user[0] = 0;
3545 else
3546 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3547
3548 STAT(ip_allocated);
3549 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3550 reuse ? "Reusing" : "Allocating", best);
3551
3552 return 1;
3553 }
3554
3555 static void free_ip_address(sessionidt s)
3556 {
3557 int i = session[s].ip_pool_index;
3558
3559
3560 CSTAT(free_ip_address);
3561
3562 if (!session[s].ip)
3563 return; // what the?
3564
3565 if (i < 0) // Is this actually part of the ip pool?
3566 i = 0;
3567
3568 STAT(ip_freed);
3569 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3570 session[s].ip = 0;
3571 ip_address_pool[i].assigned = 0;
3572 ip_address_pool[i].session = 0;
3573 ip_address_pool[i].last = time_now;
3574 }
3575
3576 //
3577 // Fsck the address pool against the session table.
3578 // Normally only called when we become a master.
3579 //
3580 // This isn't perfect: We aren't keep tracking of which
3581 // users used to have an IP address.
3582 //
3583 void rebuild_address_pool(void)
3584 {
3585 int i;
3586
3587 //
3588 // Zero the IP pool allocation, and build
3589 // a map from IP address to pool index.
3590 for (i = 1; i < MAXIPPOOL; ++i)
3591 {
3592 ip_address_pool[i].assigned = 0;
3593 ip_address_pool[i].session = 0;
3594 if (!ip_address_pool[i].address)
3595 continue;
3596
3597 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3598 }
3599
3600 for (i = 0; i < MAXSESSION; ++i)
3601 {
3602 int ipid;
3603 if (!(session[i].opened && session[i].ip))
3604 continue;
3605
3606 ipid = - lookup_ipmap(htonl(session[i].ip));
3607
3608 if (session[i].ip_pool_index < 0)
3609 {
3610 // Not allocated out of the pool.
3611 if (ipid < 1) // Not found in the pool either? good.
3612 continue;
3613
3614 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3615 i, fmtaddr(session[i].ip, 0), ipid);
3616
3617 // Fall through and process it as part of the pool.
3618 }
3619
3620
3621 if (ipid > MAXIPPOOL || ipid < 0)
3622 {
3623 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3624 ipid = -1;
3625 session[i].ip_pool_index = ipid;
3626 continue;
3627 }
3628
3629 ip_address_pool[ipid].assigned = 1;
3630 ip_address_pool[ipid].session = i;
3631 ip_address_pool[ipid].last = time_now;
3632 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3633 session[i].ip_pool_index = ipid;
3634 cache_ipmap(session[i].ip, i); // Fix the ip map.
3635 }
3636 }
3637
3638 //
3639 // Fix the address pool to match a changed session.
3640 // (usually when the master sends us an update).
3641 static void fix_address_pool(int sid)
3642 {
3643 int ipid;
3644
3645 ipid = session[sid].ip_pool_index;
3646
3647 if (ipid > ip_pool_size)
3648 return; // Ignore it. rebuild_address_pool will fix it up.
3649
3650 if (ip_address_pool[ipid].address != session[sid].ip)
3651 return; // Just ignore it. rebuild_address_pool will take care of it.
3652
3653 ip_address_pool[ipid].assigned = 1;
3654 ip_address_pool[ipid].session = sid;
3655 ip_address_pool[ipid].last = time_now;
3656 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3657 }
3658
3659 //
3660 // Add a block of addresses to the IP pool to hand out.
3661 //
3662 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3663 {
3664 int i;
3665 if (mask == 0)
3666 mask = 0xffffffff; // Host route only.
3667
3668 addr &= mask;
3669
3670 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3671 return ;
3672
3673 for (i = addr ;(i & mask) == addr; ++i)
3674 {
3675 if ((i & 0xff) == 0 || (i&0xff) == 255)
3676 continue; // Skip 0 and broadcast addresses.
3677
3678 ip_address_pool[ip_pool_size].address = i;
3679 ip_address_pool[ip_pool_size].assigned = 0;
3680 ++ip_pool_size;
3681 if (ip_pool_size >= MAXIPPOOL)
3682 {
3683 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3684 return;
3685 }
3686 }
3687 }
3688
3689 // Initialize the IP address pool
3690 static void initippool()
3691 {
3692 FILE *f;
3693 char *p;
3694 char buf[4096];
3695 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3696
3697 if (!(f = fopen(IPPOOLFILE, "r")))
3698 {
3699 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3700 exit(1);
3701 }
3702
3703 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3704 {
3705 char *pool = buf;
3706 buf[4095] = 0; // Force it to be zero terminated/
3707
3708 if (*buf == '#' || *buf == '\n')
3709 continue; // Skip comments / blank lines
3710 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3711 if ((p = (char *)strchr(buf, ':')))
3712 {
3713 in_addr_t src;
3714 *p = '\0';
3715 src = inet_addr(buf);
3716 if (src == INADDR_NONE)
3717 {
3718 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3719 exit(1);
3720 }
3721 // This entry is for a specific IP only
3722 if (src != config->bind_address)
3723 continue;
3724 *p = ':';
3725 pool = p+1;
3726 }
3727 if ((p = (char *)strchr(pool, '/')))
3728 {
3729 // It's a range
3730 int numbits = 0;
3731 in_addr_t start = 0, mask = 0;
3732
3733 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3734 *p++ = 0;
3735 if (!*p || !(numbits = atoi(p)))
3736 {
3737 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3738 continue;
3739 }
3740 start = ntohl(inet_addr(pool));
3741 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3742
3743 // Add a static route for this pool
3744 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3745 fmtaddr(htonl(start), 0), 32 + mask);
3746
3747 routeset(0, start, mask, 0, 1);
3748
3749 add_to_ip_pool(start, mask);
3750 }
3751 else
3752 {
3753 // It's a single ip address
3754 add_to_ip_pool(inet_addr(pool), 0);
3755 }
3756 }
3757 fclose(f);
3758 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3759 }
3760
3761 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
3762 {
3763 struct sockaddr_in snoop_addr = {0};
3764 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3765 return;
3766
3767 snoop_addr.sin_family = AF_INET;
3768 snoop_addr.sin_addr.s_addr = destination;
3769 snoop_addr.sin_port = ntohs(port);
3770
3771 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3772 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3773 htons(snoop_addr.sin_port));
3774
3775 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3776 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3777
3778 STAT(packets_snooped);
3779 }
3780
3781 static int dump_session(FILE **f, sessiont *s)
3782 {
3783 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3784 return 1;
3785
3786 if (!*f)
3787 {
3788 char filename[1024];
3789 char timestr[64];
3790 time_t now = time(NULL);
3791
3792 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3793 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3794
3795 if (!(*f = fopen(filename, "w")))
3796 {
3797 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3798 return 0;
3799 }
3800
3801 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3802 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3803 "# host: %s\n"
3804 "# endpoint: %s\n"
3805 "# time: %ld\n"
3806 "# uptime: %ld\n"
3807 "# format: username ip qos uptxoctets downrxoctets\n",
3808 hostname,
3809 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3810 now,
3811 now - basetime);
3812 }
3813
3814 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3815 fprintf(*f, "%s %s %d %u %u\n",
3816 s->user, // username
3817 fmtaddr(htonl(s->ip), 0), // ip
3818 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3819 (uint32_t) s->cin_delta, // uptxoctets
3820 (uint32_t) s->cout_delta); // downrxoctets
3821
3822 s->cin_delta = s->cout_delta = 0;
3823
3824 return 1;
3825 }
3826
3827 static void dump_acct_info(int all)
3828 {
3829 int i;
3830 FILE *f = NULL;
3831
3832
3833 CSTAT(dump_acct_info);
3834
3835 if (shut_acct_n)
3836 {
3837 for (i = 0; i < shut_acct_n; i++)
3838 dump_session(&f, &shut_acct[i]);
3839
3840 shut_acct_n = 0;
3841 }
3842
3843 if (all)
3844 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3845 dump_session(&f, &session[i]);
3846
3847 if (f)
3848 fclose(f);
3849 }
3850
3851 // Main program
3852 int main(int argc, char *argv[])
3853 {
3854 int i;
3855 int optdebug = 0;
3856 char *optconfig = CONFIGFILE;
3857
3858 time(&basetime); // start clock
3859
3860 // scan args
3861 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3862 {
3863 switch (i)
3864 {
3865 case 'd':
3866 if (fork()) exit(0);
3867 setsid();
3868 freopen("/dev/null", "r", stdin);
3869 freopen("/dev/null", "w", stdout);
3870 freopen("/dev/null", "w", stderr);
3871 break;
3872 case 'v':
3873 optdebug++;
3874 break;
3875 case 'c':
3876 optconfig = optarg;
3877 break;
3878 case 'h':
3879 snprintf(hostname, sizeof(hostname), "%s", optarg);
3880 break;
3881 default:
3882 printf("Args are:\n"
3883 "\t-d\t\tDetach from terminal\n"
3884 "\t-c <file>\tConfig file\n"
3885 "\t-h <hostname>\tForce hostname\n"
3886 "\t-v\t\tDebug\n");
3887
3888 return (0);
3889 break;
3890 }
3891 }
3892
3893 // Start the timer routine off
3894 time(&time_now);
3895 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3896 signal(SIGALRM, sigalrm_handler);
3897 siginterrupt(SIGALRM, 0);
3898
3899 initplugins();
3900 initdata(optdebug, optconfig);
3901
3902 init_cli(hostname);
3903 read_config_file();
3904 init_tbf(config->num_tbfs);
3905
3906 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3907 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3908 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3909 {
3910 struct rlimit rlim;
3911 rlim.rlim_cur = RLIM_INFINITY;
3912 rlim.rlim_max = RLIM_INFINITY;
3913 // Remove the maximum core size
3914 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3915 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3916
3917 // Make core dumps go to /tmp
3918 chdir("/tmp");
3919 }
3920
3921 if (config->scheduler_fifo)
3922 {
3923 int ret;
3924 struct sched_param params = {0};
3925 params.sched_priority = 1;
3926
3927 if (get_nprocs() < 2)
3928 {
3929 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3930 config->scheduler_fifo = 0;
3931 }
3932 else
3933 {
3934 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3935 {
3936 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3937 }
3938 else
3939 {
3940 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3941 config->scheduler_fifo = 0;
3942 }
3943 }
3944 }
3945
3946 /* Set up the cluster communications port. */
3947 if (cluster_init() < 0)
3948 exit(1);
3949
3950 inittun();
3951 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3952
3953 initudp();
3954 initrad();
3955 initippool();
3956
3957 // seed prng
3958 {
3959 unsigned seed = time_now ^ getpid();
3960 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
3961 srand(seed);
3962 }
3963
3964 signal(SIGHUP, sighup_handler);
3965 signal(SIGCHLD, sigchild_handler);
3966 signal(SIGTERM, shutdown_handler);
3967 signal(SIGINT, shutdown_handler);
3968 signal(SIGQUIT, shutdown_handler);
3969
3970 // Prevent us from getting paged out
3971 if (config->lock_pages)
3972 {
3973 if (!mlockall(MCL_CURRENT))
3974 LOG(1, 0, 0, "Locking pages into memory\n");
3975 else
3976 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3977 }
3978
3979 alarm(1);
3980
3981 // Drop privileges here
3982 if (config->target_uid > 0 && geteuid() == 0)
3983 setuid(config->target_uid);
3984
3985 mainloop();
3986
3987 /* remove plugins (so cleanup code gets run) */
3988 plugins_done();
3989
3990 // Remove the PID file if we wrote it
3991 if (config->wrote_pid && *config->pid_file == '/')
3992 unlink(config->pid_file);
3993
3994 /* kill CLI children */
3995 signal(SIGTERM, SIG_IGN);
3996 kill(0, SIGTERM);
3997 return 0;
3998 }
3999
4000 static void sighup_handler(int sig)
4001 {
4002 if (log_stream)
4003 {
4004 if (log_stream != stderr)
4005 fclose(log_stream);
4006
4007 log_stream = NULL;
4008 }
4009
4010 read_config_file();
4011 }
4012
4013 static void sigalrm_handler(int sig)
4014 {
4015 // Log current traffic stats
4016
4017 snprintf(config->bandwidth, sizeof(config->bandwidth),
4018 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4019 (udp_rx / 1024.0 / 1024.0 * 8),
4020 (eth_tx / 1024.0 / 1024.0 * 8),
4021 (eth_rx / 1024.0 / 1024.0 * 8),
4022 (udp_tx / 1024.0 / 1024.0 * 8),
4023 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4024 udp_rx_pkt, eth_rx_pkt);
4025
4026 udp_tx = udp_rx = 0;
4027 udp_rx_pkt = eth_rx_pkt = 0;
4028 eth_tx = eth_rx = 0;
4029
4030 if (config->dump_speed)
4031 printf("%s\n", config->bandwidth);
4032
4033 // Update the internal time counter
4034 time(&time_now);
4035 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4036 alarm(1);
4037
4038 {
4039 // Run timer hooks
4040 struct param_timer p = { time_now };
4041 run_plugins(PLUGIN_TIMER, &p);
4042 }
4043
4044 }
4045
4046 static void shutdown_handler(int sig)
4047 {
4048 LOG(1, 0, 0, "Shutting down\n");
4049 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4050 }
4051
4052 static void sigchild_handler(int sig)
4053 {
4054 while (waitpid(-1, NULL, WNOHANG) > 0)
4055 ;
4056 }
4057
4058 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
4059 {
4060 MD5_CTX ctx;
4061 *challenge_response = NULL;
4062
4063 if (!*config->l2tpsecret)
4064 {
4065 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4066 return;
4067 }
4068
4069 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4070
4071 *challenge_response = (char *)calloc(17, 1);
4072
4073 MD5Init(&ctx);
4074 MD5Update(&ctx, &id, 1);
4075 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4076 MD5Update(&ctx, challenge, challenge_length);
4077 MD5Final(*challenge_response, &ctx);
4078
4079 return;
4080 }
4081
4082 static int facility_value(char *name)
4083 {
4084 int i;
4085 for (i = 0; facilitynames[i].c_name; i++)
4086 {
4087 if (strcmp(facilitynames[i].c_name, name) == 0)
4088 return facilitynames[i].c_val;
4089 }
4090 return 0;
4091 }
4092
4093 static void update_config()
4094 {
4095 int i;
4096 char *p;
4097 static int timeout = 0;
4098 static int interval = 0;
4099
4100 // Update logging
4101 closelog();
4102 syslog_log = 0;
4103 if (log_stream)
4104 {
4105 if (log_stream != stderr)
4106 fclose(log_stream);
4107
4108 log_stream = NULL;
4109 }
4110
4111 if (*config->log_filename)
4112 {
4113 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4114 {
4115 char *p = config->log_filename + 7;
4116 if (*p)
4117 {
4118 openlog("l2tpns", LOG_PID, facility_value(p));
4119 syslog_log = 1;
4120 }
4121 }
4122 else if (strchr(config->log_filename, '/') == config->log_filename)
4123 {
4124 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4125 {
4126 fseek(log_stream, 0, SEEK_END);
4127 setbuf(log_stream, NULL);
4128 }
4129 else
4130 {
4131 log_stream = stderr;
4132 setbuf(log_stream, NULL);
4133 }
4134 }
4135 }
4136 else
4137 {
4138 log_stream = stderr;
4139 setbuf(log_stream, NULL);
4140 }
4141
4142 // Update radius
4143 config->numradiusservers = 0;
4144 for (i = 0; i < MAXRADSERVER; i++)
4145 if (config->radiusserver[i])
4146 {
4147 config->numradiusservers++;
4148 // Set radius port: if not set, take the port from the
4149 // first radius server. For the first radius server,
4150 // take the #defined default value from l2tpns.h
4151
4152 // test twice, In case someone works with
4153 // a secondary radius server without defining
4154 // a primary one, this will work even then.
4155 if (i > 0 && !config->radiusport[i])
4156 config->radiusport[i] = config->radiusport[i-1];
4157 if (!config->radiusport[i])
4158 config->radiusport[i] = RADPORT;
4159 }
4160
4161 if (!config->numradiusservers)
4162 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4163
4164 // parse radius_authtypes_s
4165 config->radius_authtypes = config->radius_authprefer = 0;
4166 p = config->radius_authtypes_s;
4167 while (p && *p)
4168 {
4169 char *s = strpbrk(p, " \t,");
4170 int type = 0;
4171
4172 if (s)
4173 {
4174 *s++ = 0;
4175 while (*s == ' ' || *s == '\t')
4176 s++;
4177
4178 if (!*s)
4179 s = 0;
4180 }
4181
4182 if (!strncasecmp("chap", p, strlen(p)))
4183 type = AUTHCHAP;
4184 else if (!strncasecmp("pap", p, strlen(p)))
4185 type = AUTHPAP;
4186 else
4187 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4188
4189 config->radius_authtypes |= type;
4190 if (!config->radius_authprefer)
4191 config->radius_authprefer = type;
4192
4193 p = s;
4194 }
4195
4196 if (!config->radius_authtypes)
4197 {
4198 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4199 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4200 }
4201
4202 // normalise radius_authtypes_s
4203 if (config->radius_authprefer == AUTHPAP)
4204 {
4205 strcpy(config->radius_authtypes_s, "pap");
4206 if (config->radius_authtypes & AUTHCHAP)
4207 strcat(config->radius_authtypes_s, ", chap");
4208 }
4209 else
4210 {
4211 strcpy(config->radius_authtypes_s, "chap");
4212 if (config->radius_authtypes & AUTHPAP)
4213 strcat(config->radius_authtypes_s, ", pap");
4214 }
4215
4216 if (!config->radius_dae_port)
4217 config->radius_dae_port = DAEPORT;
4218
4219 // re-initialise the random number source
4220 initrandom(config->random_device);
4221
4222 // Update plugins
4223 for (i = 0; i < MAXPLUGINS; i++)
4224 {
4225 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4226 continue;
4227
4228 if (*config->plugins[i])
4229 {
4230 // Plugin added
4231 add_plugin(config->plugins[i]);
4232 }
4233 else if (*config->old_plugins[i])
4234 {
4235 // Plugin removed
4236 remove_plugin(config->old_plugins[i]);
4237 }
4238 }
4239
4240 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4241 if (!config->multi_read_count) config->multi_read_count = 10;
4242 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4243 if (!*config->cluster_interface)
4244 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4245
4246 if (!config->cluster_hb_interval)
4247 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4248
4249 if (!config->cluster_hb_timeout)
4250 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4251
4252 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4253 {
4254 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4255 // late, ensure we're sufficiently larger than that
4256 int t = 4 * config->cluster_hb_interval + 11;
4257
4258 if (config->cluster_hb_timeout < t)
4259 {
4260 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4261 config->cluster_hb_timeout = t;
4262 }
4263
4264 // Push timing changes to the slaves immediately if we're the master
4265 if (config->cluster_iam_master)
4266 cluster_heartbeat();
4267
4268 interval = config->cluster_hb_interval;
4269 timeout = config->cluster_hb_timeout;
4270 }
4271
4272 // Write PID file
4273 if (*config->pid_file == '/' && !config->wrote_pid)
4274 {
4275 FILE *f;
4276 if ((f = fopen(config->pid_file, "w")))
4277 {
4278 fprintf(f, "%d\n", getpid());
4279 fclose(f);
4280 config->wrote_pid = 1;
4281 }
4282 else
4283 {
4284 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4285 }
4286 }
4287
4288 config->reload_config = 0;
4289 }
4290
4291 static void read_config_file()
4292 {
4293 FILE *f;
4294
4295 if (!config->config_file) return;
4296 if (!(f = fopen(config->config_file, "r")))
4297 {
4298 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4299 return;
4300 }
4301
4302 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4303 cli_do_file(f);
4304 LOG(3, 0, 0, "Done reading config file\n");
4305 fclose(f);
4306 update_config();
4307 }
4308
4309 int sessionsetup(tunnelidt t, sessionidt s)
4310 {
4311 // A session now exists, set it up
4312 in_addr_t ip;
4313 char *user;
4314 sessionidt i;
4315 int r;
4316
4317 CSTAT(sessionsetup);
4318
4319 LOG(3, s, t, "Doing session setup for session\n");
4320
4321 if (!session[s].ip)
4322 {
4323 assign_ip_address(s);
4324 if (!session[s].ip)
4325 {
4326 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4327 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4328 return 0;
4329 }
4330 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4331 fmtaddr(htonl(session[s].ip), 0));
4332 }
4333
4334
4335 // Make sure this is right
4336 session[s].tunnel = t;
4337
4338 // zap old sessions with same IP and/or username
4339 // Don't kill gardened sessions - doing so leads to a DoS
4340 // from someone who doesn't need to know the password
4341 {
4342 ip = session[s].ip;
4343 user = session[s].user;
4344 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4345 {
4346 if (i == s) continue;
4347 if (!session[s].opened) continue;
4348 if (ip == session[i].ip)
4349 {
4350 sessionkill(i, "Duplicate IP address");
4351 continue;
4352 }
4353
4354 if (config->allow_duplicate_users) continue;
4355 if (session[s].walled_garden || session[i].walled_garden) continue;
4356 if (!strcasecmp(user, session[i].user))
4357 sessionkill(i, "Duplicate session for users");
4358 }
4359 }
4360
4361 {
4362 int routed = 0;
4363
4364 // Add the route for this session.
4365 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4366 {
4367 if ((session[s].ip & session[s].route[r].mask) ==
4368 (session[s].route[r].ip & session[s].route[r].mask))
4369 routed++;
4370
4371 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4372 }
4373
4374 // Static IPs need to be routed if not already
4375 // convered by a Framed-Route. Anything else is part
4376 // of the IP address pool and is already routed, it
4377 // just needs to be added to the IP cache.
4378 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4379 if (session[s].ip_pool_index == -1) // static ip
4380 {
4381 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4382 }
4383 else
4384 cache_ipmap(session[s].ip, s);
4385 }
4386
4387 if (!session[s].unique_id)
4388 {
4389 // did this session just finish radius?
4390 LOG(3, s, t, "Sending initial IPCP to client\n");
4391 sendipcp(t, s);
4392 session[s].unique_id = ++last_id;
4393 }
4394
4395 // Run the plugin's against this new session.
4396 {
4397 struct param_new_session data = { &tunnel[t], &session[s] };
4398 run_plugins(PLUGIN_NEW_SESSION, &data);
4399 }
4400
4401 // Allocate TBFs if throttled
4402 if (session[s].throttle_in || session[s].throttle_out)
4403 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4404
4405 session[s].last_packet = time_now;
4406
4407 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4408 fmtaddr(htonl(session[s].ip), 0),
4409 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4410
4411 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4412
4413 return 1; // RADIUS OK and IP allocated, done...
4414 }
4415
4416 //
4417 // This session just got dropped on us by the master or something.
4418 // Make sure our tables up up to date...
4419 //
4420 int load_session(sessionidt s, sessiont *new)
4421 {
4422 int i;
4423 int newip = 0;
4424
4425 // Sanity checks.
4426 if (new->ip_pool_index >= MAXIPPOOL ||
4427 new->tunnel >= MAXTUNNEL)
4428 {
4429 LOG(0, s, 0, "Strange session update received!\n");
4430 // FIXME! What to do here?
4431 return 0;
4432 }
4433
4434 //
4435 // Ok. All sanity checks passed. Now we're committed to
4436 // loading the new session.
4437 //
4438
4439 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4440
4441 // See if routes/ip cache need updating
4442 if (new->ip != session[s].ip)
4443 newip++;
4444
4445 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4446 if (new->route[i].ip != session[s].route[i].ip ||
4447 new->route[i].mask != session[s].route[i].mask)
4448 newip++;
4449
4450 // needs update
4451 if (newip)
4452 {
4453 int routed = 0;
4454
4455 // remove old routes...
4456 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4457 {
4458 if ((session[s].ip & session[s].route[i].mask) ==
4459 (session[s].route[i].ip & session[s].route[i].mask))
4460 routed++;
4461
4462 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4463 }
4464
4465 // ...ip
4466 if (session[s].ip)
4467 {
4468 if (session[s].ip_pool_index == -1) // static IP
4469 {
4470 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4471 }
4472 else // It's part of the IP pool, remove it manually.
4473 uncache_ipmap(session[s].ip);
4474 }
4475
4476 routed = 0;
4477
4478 // add new routes...
4479 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4480 {
4481 if ((new->ip & new->route[i].mask) ==
4482 (new->route[i].ip & new->route[i].mask))
4483 routed++;
4484
4485 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4486 }
4487
4488 // ...ip
4489 if (new->ip)
4490 {
4491 // If there's a new one, add it.
4492 if (new->ip_pool_index == -1)
4493 {
4494 if (!routed) routeset(s, new->ip, 0, 0, 1);
4495 }
4496 else
4497 cache_ipmap(new->ip, s);
4498 }
4499 }
4500
4501 // check v6 routing
4502 if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
4503 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4504
4505 // check filters
4506 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4507 {
4508 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4509 new->filter_in = 0;
4510 }
4511
4512 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4513 {
4514 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4515 new->filter_out = 0;
4516 }
4517
4518 if (new->filter_in != session[s].filter_in)
4519 {
4520 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4521 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4522 }
4523
4524 if (new->filter_out != session[s].filter_out)
4525 {
4526 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4527 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4528 }
4529
4530 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4531 // for walking the sessions to forward byte counts to the master.
4532 config->cluster_highest_sessionid = s;
4533
4534 // TEMP: old session struct used a uint32_t to define the throttle
4535 // speed for both up/down, new uses a uint16_t for each. Deal with
4536 // sessions from an old master for migration.
4537 if (new->throttle_out == 0 && new->tbf_out)
4538 new->throttle_out = new->throttle_in;
4539
4540 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4541
4542 // Do fixups into address pool.
4543 if (new->ip_pool_index != -1)
4544 fix_address_pool(s);
4545
4546 return 1;
4547 }
4548
4549 static void initplugins()
4550 {
4551 int i;
4552
4553 loaded_plugins = ll_init();
4554 // Initialize the plugins to nothing
4555 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4556 plugins[i] = ll_init();
4557 }
4558
4559 static void *open_plugin(char *plugin_name, int load)
4560 {
4561 char path[256] = "";
4562
4563 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4564 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4565 return dlopen(path, RTLD_NOW);
4566 }
4567
4568 // plugin callback to get a config value
4569 static void *getconfig(char *key, enum config_typet type)
4570 {
4571 int i;
4572
4573 for (i = 0; config_values[i].key; i++)
4574 {
4575 if (!strcmp(config_values[i].key, key))
4576 {
4577 if (config_values[i].type == type)
4578 return ((void *) config) + config_values[i].offset;
4579
4580 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4581 key, type, config_values[i].type);
4582
4583 return 0;
4584 }
4585 }
4586
4587 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4588 return 0;
4589 }
4590
4591 static int add_plugin(char *plugin_name)
4592 {
4593 static struct pluginfuncs funcs = {
4594 _log,
4595 _log_hex,
4596 fmtaddr,
4597 sessionbyuser,
4598 sessiontbysessionidt,
4599 sessionidtbysessiont,
4600 radiusnew,
4601 radiussend,
4602 getconfig,
4603 sessionshutdown,
4604 sessionkill,
4605 throttle_session,
4606 cluster_send_session,
4607 };
4608
4609 void *p = open_plugin(plugin_name, 1);
4610 int (*initfunc)(struct pluginfuncs *);
4611 int i;
4612
4613 if (!p)
4614 {
4615 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4616 return -1;
4617 }
4618
4619 if (ll_contains(loaded_plugins, p))
4620 {
4621 dlclose(p);
4622 return 0; // already loaded
4623 }
4624
4625 {
4626 int *v = dlsym(p, "plugin_api_version");
4627 if (!v || *v != PLUGIN_API_VERSION)
4628 {
4629 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4630 dlclose(p);
4631 return -1;
4632 }
4633 }
4634
4635 if ((initfunc = dlsym(p, "plugin_init")))
4636 {
4637 if (!initfunc(&funcs))
4638 {
4639 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4640 dlclose(p);
4641 return -1;
4642 }
4643 }
4644
4645 ll_push(loaded_plugins, p);
4646
4647 for (i = 0; i < max_plugin_functions; i++)
4648 {
4649 void *x;
4650 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4651 {
4652 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4653 ll_push(plugins[i], x);
4654 }
4655 }
4656
4657 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4658 return 1;
4659 }
4660
4661 static void run_plugin_done(void *plugin)
4662 {
4663 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4664
4665 if (donefunc)
4666 donefunc();
4667 }
4668
4669 static int remove_plugin(char *plugin_name)
4670 {
4671 void *p = open_plugin(plugin_name, 0);
4672 int loaded = 0;
4673
4674 if (!p)
4675 return -1;
4676
4677 if (ll_contains(loaded_plugins, p))
4678 {
4679 int i;
4680 for (i = 0; i < max_plugin_functions; i++)
4681 {
4682 void *x;
4683 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4684 ll_delete(plugins[i], x);
4685 }
4686
4687 ll_delete(loaded_plugins, p);
4688 run_plugin_done(p);
4689 loaded = 1;
4690 }
4691
4692 dlclose(p);
4693 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4694 return loaded;
4695 }
4696
4697 int run_plugins(int plugin_type, void *data)
4698 {
4699 int (*func)(void *data);
4700
4701 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4702 return PLUGIN_RET_ERROR;
4703
4704 ll_reset(plugins[plugin_type]);
4705 while ((func = ll_next(plugins[plugin_type])))
4706 {
4707 int r = func(data);
4708
4709 if (r != PLUGIN_RET_OK)
4710 return r; // stop here
4711 }
4712
4713 return PLUGIN_RET_OK;
4714 }
4715
4716 static void plugins_done()
4717 {
4718 void *p;
4719
4720 ll_reset(loaded_plugins);
4721 while ((p = ll_next(loaded_plugins)))
4722 run_plugin_done(p);
4723 }
4724
4725 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4726 {
4727 struct nsctl request;
4728 struct nsctl response;
4729 int type = unpack_control(&request, buf, len);
4730 int r;
4731 void *p;
4732
4733 if (log_stream && config->debug >= 4)
4734 {
4735 if (type < 0)
4736 {
4737 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4738 fmtaddr(addr->sin_addr.s_addr, 0), type);
4739 }
4740 else
4741 {
4742 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4743 dump_control(&request, log_stream);
4744 }
4745 }
4746
4747 switch (type)
4748 {
4749 case NSCTL_REQ_LOAD:
4750 if (request.argc != 1)
4751 {
4752 response.type = NSCTL_RES_ERR;
4753 response.argc = 1;
4754 response.argv[0] = "name of plugin required";
4755 }
4756 else if ((r = add_plugin(request.argv[0])) < 1)
4757 {
4758 response.type = NSCTL_RES_ERR;
4759 response.argc = 1;
4760 response.argv[0] = !r
4761 ? "plugin already loaded"
4762 : "error loading plugin";
4763 }
4764 else
4765 {
4766 response.type = NSCTL_RES_OK;
4767 response.argc = 0;
4768 }
4769
4770 break;
4771
4772 case NSCTL_REQ_UNLOAD:
4773 if (request.argc != 1)
4774 {
4775 response.type = NSCTL_RES_ERR;
4776 response.argc = 1;
4777 response.argv[0] = "name of plugin required";
4778 }
4779 else if ((r = remove_plugin(request.argv[0])) < 1)
4780 {
4781 response.type = NSCTL_RES_ERR;
4782 response.argc = 1;
4783 response.argv[0] = !r
4784 ? "plugin not loaded"
4785 : "plugin not found";
4786 }
4787 else
4788 {
4789 response.type = NSCTL_RES_OK;
4790 response.argc = 0;
4791 }
4792
4793 break;
4794
4795 case NSCTL_REQ_HELP:
4796 response.type = NSCTL_RES_OK;
4797 response.argc = 0;
4798
4799 ll_reset(loaded_plugins);
4800 while ((p = ll_next(loaded_plugins)))
4801 {
4802 char **help = dlsym(p, "plugin_control_help");
4803 while (response.argc < 0xff && help && *help)
4804 response.argv[response.argc++] = *help++;
4805 }
4806
4807 break;
4808
4809 case NSCTL_REQ_CONTROL:
4810 {
4811 struct param_control param = {
4812 config->cluster_iam_master,
4813 request.argc,
4814 request.argv,
4815 0,
4816 NULL,
4817 };
4818
4819 int r = run_plugins(PLUGIN_CONTROL, &param);
4820
4821 if (r == PLUGIN_RET_ERROR)
4822 {
4823 response.type = NSCTL_RES_ERR;
4824 response.argc = 1;
4825 response.argv[0] = param.additional
4826 ? param.additional
4827 : "error returned by plugin";
4828 }
4829 else if (r == PLUGIN_RET_NOTMASTER)
4830 {
4831 static char msg[] = "must be run on master: 000.000.000.000";
4832
4833 response.type = NSCTL_RES_ERR;
4834 response.argc = 1;
4835 if (config->cluster_master_address)
4836 {
4837 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4838 response.argv[0] = msg;
4839 }
4840 else
4841 {
4842 response.argv[0] = "must be run on master: none elected";
4843 }
4844 }
4845 else if (!(param.response & NSCTL_RESPONSE))
4846 {
4847 response.type = NSCTL_RES_ERR;
4848 response.argc = 1;
4849 response.argv[0] = param.response
4850 ? "unrecognised response value from plugin"
4851 : "unhandled action";
4852 }
4853 else
4854 {
4855 response.type = param.response;
4856 response.argc = 0;
4857 if (param.additional)
4858 {
4859 response.argc = 1;
4860 response.argv[0] = param.additional;
4861 }
4862 }
4863 }
4864
4865 break;
4866
4867 default:
4868 response.type = NSCTL_RES_ERR;
4869 response.argc = 1;
4870 response.argv[0] = "error unpacking control packet";
4871 }
4872
4873 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4874 if (!buf)
4875 {
4876 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4877 return;
4878 }
4879
4880 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4881 if (r > 0)
4882 {
4883 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4884 if (log_stream && config->debug >= 4)
4885 {
4886 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4887 dump_control(&response, log_stream);
4888 }
4889 }
4890 else
4891 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4892 fmtaddr(addr->sin_addr.s_addr, 0), r);
4893
4894 free(buf);
4895 }
4896
4897 static tunnelidt new_tunnel()
4898 {
4899 tunnelidt i;
4900 for (i = 1; i < MAXTUNNEL; i++)
4901 {
4902 if (tunnel[i].state == TUNNELFREE)
4903 {
4904 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4905 if (i > config->cluster_highest_tunnelid)
4906 config->cluster_highest_tunnelid = i;
4907 return i;
4908 }
4909 }
4910 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4911 return 0;
4912 }
4913
4914 //
4915 // We're becoming the master. Do any required setup..
4916 //
4917 // This is principally telling all the plugins that we're
4918 // now a master, and telling them about all the sessions
4919 // that are active too..
4920 //
4921 void become_master(void)
4922 {
4923 int s, i;
4924 static struct event_data d[RADIUS_FDS];
4925 struct epoll_event e;
4926
4927 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4928
4929 // running a bunch of iptables commands is slow and can cause
4930 // the master to drop tunnels on takeover--kludge around the
4931 // problem by forking for the moment (note: race)
4932 if (!fork_and_close())
4933 {
4934 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4935 {
4936 if (!session[s].opened) // Not an in-use session.
4937 continue;
4938
4939 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4940 }
4941 exit(0);
4942 }
4943
4944 // add radius fds
4945 e.events = EPOLLIN;
4946 for (i = 0; i < RADIUS_FDS; i++)
4947 {
4948 d[i].type = FD_TYPE_RADIUS;
4949 d[i].index = i;
4950 e.data.ptr = &d[i];
4951
4952 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
4953 }
4954 }
4955
4956 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4957 {
4958 int s, i;
4959 int count = 0;
4960 int buckets[64];
4961
4962 if (CLI_HELP_REQUESTED)
4963 return CLI_HELP_NO_ARGS;
4964
4965 time(&time_now);
4966 for (i = 0; i < 64;++i) buckets[i] = 0;
4967
4968 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4969 {
4970 int idle;
4971 if (!session[s].opened)
4972 continue;
4973
4974 idle = time_now - session[s].last_packet;
4975 idle /= 5 ; // In multiples of 5 seconds.
4976 if (idle < 0)
4977 idle = 0;
4978 if (idle > 63)
4979 idle = 63;
4980
4981 ++count;
4982 ++buckets[idle];
4983 }
4984
4985 for (i = 0; i < 63; ++i)
4986 {
4987 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4988 }
4989 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4990 cli_print(cli, "%d total sessions open.", count);
4991 return CLI_OK;
4992 }
4993
4994 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4995 {
4996 int s, i;
4997 int count = 0;
4998 int buckets[64];
4999
5000 if (CLI_HELP_REQUESTED)
5001 return CLI_HELP_NO_ARGS;
5002
5003 time(&time_now);
5004 for (i = 0; i < 64;++i) buckets[i] = 0;
5005
5006 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5007 {
5008 int open = 0, d;
5009 if (!session[s].opened)
5010 continue;
5011
5012 d = time_now - session[s].opened;
5013 if (d < 0)
5014 d = 0;
5015 while (d > 1 && open < 32)
5016 {
5017 ++open;
5018 d >>= 1; // half.
5019 }
5020 ++count;
5021 ++buckets[open];
5022 }
5023
5024 s = 1;
5025 for (i = 0; i < 30; ++i)
5026 {
5027 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5028 s <<= 1;
5029 }
5030 cli_print(cli, "%d total sessions open.", count);
5031 return CLI_OK;
5032 }
5033
5034 /* Unhide an avp.
5035 *
5036 * This unencodes the AVP using the L2TP secret and the previously
5037 * stored random vector. It overwrites the hidden data with the
5038 * unhidden AVP subformat.
5039 */
5040 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5041 {
5042 MD5_CTX ctx;
5043 uint8_t digest[16];
5044 uint8_t *last;
5045 size_t d = 0;
5046 uint16_t m = htons(type);
5047
5048 // Compute initial pad
5049 MD5Init(&ctx);
5050 MD5Update(&ctx, (unsigned char *) &m, 2);
5051 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5052 MD5Update(&ctx, vector, vec_len);
5053 MD5Final(digest, &ctx);
5054
5055 // pointer to last decoded 16 octets
5056 last = value;
5057
5058 while (len > 0)
5059 {
5060 // calculate a new pad based on the last decoded block
5061 if (d >= sizeof(digest))
5062 {
5063 MD5Init(&ctx);
5064 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5065 MD5Update(&ctx, last, sizeof(digest));
5066 MD5Final(digest, &ctx);
5067
5068 d = 0;
5069 last = value;
5070 }
5071
5072 *value++ ^= digest[d++];
5073 len--;
5074 }
5075 }
5076
5077 int find_filter(char const *name, size_t len)
5078 {
5079 int free = -1;
5080 int i;
5081
5082 for (i = 0; i < MAXFILTER; i++)
5083 {
5084 if (!*ip_filters[i].name)
5085 {
5086 if (free < 0)
5087 free = i;
5088
5089 continue;
5090 }
5091
5092 if (strlen(ip_filters[i].name) != len)
5093 continue;
5094
5095 if (!strncmp(ip_filters[i].name, name, len))
5096 return i;
5097 }
5098
5099 return free;
5100 }
5101
5102 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5103 {
5104 switch (p->op)
5105 {
5106 case FILTER_PORT_OP_EQ: return port == p->port;
5107 case FILTER_PORT_OP_NEQ: return port != p->port;
5108 case FILTER_PORT_OP_GT: return port > p->port;
5109 case FILTER_PORT_OP_LT: return port < p->port;
5110 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5111 }
5112
5113 return 0;
5114 }
5115
5116 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5117 {
5118 switch (op)
5119 {
5120 case FILTER_FLAG_OP_ANY:
5121 return (flags & sflags) || (~flags & cflags);
5122
5123 case FILTER_FLAG_OP_ALL:
5124 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5125
5126 case FILTER_FLAG_OP_EST:
5127 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5128 }
5129
5130 return 0;
5131 }
5132
5133 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5134 {
5135 uint16_t frag_offset;
5136 uint8_t proto;
5137 in_addr_t src_ip;
5138 in_addr_t dst_ip;
5139 uint16_t src_port = 0;
5140 uint16_t dst_port = 0;
5141 uint8_t flags = 0;
5142 ip_filter_rulet *rule;
5143
5144 if (len < 20) // up to end of destination address
5145 return 0;
5146
5147 if ((*buf >> 4) != 4) // IPv4
5148 return 0;
5149
5150 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5151 proto = buf[9];
5152 src_ip = *(in_addr_t *) (buf + 12);
5153 dst_ip = *(in_addr_t *) (buf + 16);
5154
5155 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5156 {
5157 int l = (buf[0] & 0xf) * 4; // length of IP header
5158 if (len < l + 4) // ports
5159 return 0;
5160
5161 src_port = ntohs(*(uint16_t *) (buf + l));
5162 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5163 if (proto == IPPROTO_TCP)
5164 {
5165 if (len < l + 14) // flags
5166 return 0;
5167
5168 flags = buf[l + 13] & 0x3f;
5169 }
5170 }
5171
5172 for (rule = ip_filters[filter].rules; rule->action; rule++)
5173 {
5174 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5175 continue;
5176
5177 if (rule->src_wild != INADDR_BROADCAST &&
5178 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5179 continue;
5180
5181 if (rule->dst_wild != INADDR_BROADCAST &&
5182 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5183 continue;
5184
5185 if (frag_offset)
5186 {
5187 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5188 continue;
5189 }
5190 else
5191 {
5192 if (rule->frag)
5193 continue;
5194
5195 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5196 {
5197 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5198 continue;
5199
5200 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5201 continue;
5202
5203 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5204 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5205 continue;
5206 }
5207 }
5208
5209 // matched
5210 rule->counter++;
5211 return rule->action == FILTER_ACTION_PERMIT;
5212 }
5213
5214 // default deny
5215 return 0;
5216 }