handle rejection of MRU negotiation by peer
[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 1.124 2005-08-29 06:17:53 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
79 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
80
81 static void *ip_hash[256]; // Mapping from IP address to session structures.
82 struct ipv6radix {
83 int sess;
84 struct ipv6radix *branch;
85 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
86
87 // Traffic counters.
88 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
89 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
90 uint32_t eth_tx = 0;
91
92 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
93 time_t time_now = 0; // Current time in seconds since epoch.
94 static char time_now_string[64] = {0}; // Current time as a string.
95 char main_quit = 0; // True if we're in the process of exiting.
96 linked_list *loaded_plugins;
97 linked_list *plugins[MAX_PLUGIN_TYPES];
98
99 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
100 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
101
102 config_descriptt config_values[] = {
103 CONFIG("debug", debug, INT),
104 CONFIG("log_file", log_filename, STRING),
105 CONFIG("pid_file", pid_file, STRING),
106 CONFIG("random_device", random_device, STRING),
107 CONFIG("l2tp_secret", l2tpsecret, STRING),
108 CONFIG("ppp_restart_time", ppp_restart_time, INT),
109 CONFIG("ppp_max_configure", ppp_max_configure, INT),
110 CONFIG("ppp_max_failure", ppp_max_failure, INT),
111 CONFIG("primary_dns", default_dns1, IPv4),
112 CONFIG("secondary_dns", default_dns2, IPv4),
113 CONFIG("primary_radius", radiusserver[0], IPv4),
114 CONFIG("secondary_radius", radiusserver[1], IPv4),
115 CONFIG("primary_radius_port", radiusport[0], SHORT),
116 CONFIG("secondary_radius_port", radiusport[1], SHORT),
117 CONFIG("radius_accounting", radius_accounting, BOOL),
118 CONFIG("radius_interim", radius_interim, INT),
119 CONFIG("radius_secret", radiussecret, STRING),
120 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
121 CONFIG("radius_dae_port", radius_dae_port, SHORT),
122 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
123 CONFIG("bind_address", bind_address, IPv4),
124 CONFIG("peer_address", peer_address, IPv4),
125 CONFIG("send_garp", send_garp, BOOL),
126 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
127 CONFIG("throttle_buckets", num_tbfs, INT),
128 CONFIG("accounting_dir", accounting_dir, STRING),
129 CONFIG("setuid", target_uid, INT),
130 CONFIG("dump_speed", dump_speed, BOOL),
131 CONFIG("multi_read_count", multi_read_count, INT),
132 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
133 CONFIG("lock_pages", lock_pages, BOOL),
134 CONFIG("icmp_rate", icmp_rate, INT),
135 CONFIG("packet_limit", max_packets, INT),
136 CONFIG("cluster_address", cluster_address, IPv4),
137 CONFIG("cluster_interface", cluster_interface, STRING),
138 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
139 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
140 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
141 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
142 { NULL, 0, 0, 0 },
143 };
144
145 static char *plugin_functions[] = {
146 NULL,
147 "plugin_pre_auth",
148 "plugin_post_auth",
149 "plugin_packet_rx",
150 "plugin_packet_tx",
151 "plugin_timer",
152 "plugin_new_session",
153 "plugin_kill_session",
154 "plugin_control",
155 "plugin_radius_response",
156 "plugin_radius_reset",
157 "plugin_become_master",
158 "plugin_new_session_master",
159 };
160
161 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
162
163 // Counters for shutdown sessions
164 static sessiont shut_acct[8192];
165 static sessionidt shut_acct_n = 0;
166
167 tunnelt *tunnel = NULL; // Array of tunnel structures.
168 sessiont *session = NULL; // Array of session structures.
169 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
170 radiust *radius = NULL; // Array of radius structures.
171 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
172 ip_filtert *ip_filters = NULL; // Array of named filters.
173 static controlt *controlfree = 0;
174 struct Tstats *_statistics = NULL;
175 #ifdef RINGBUFFER
176 struct Tringbuffer *ringbuffer = NULL;
177 #endif
178
179 static void cache_ipmap(in_addr_t ip, int s);
180 static void uncache_ipmap(in_addr_t ip);
181 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
182 static void free_ip_address(sessionidt s);
183 static void dump_acct_info(int all);
184 static void sighup_handler(int sig);
185 static void sigalrm_handler(int sig);
186 static void shutdown_handler(int sig);
187 static void sigchild_handler(int sig);
188 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
189 static void update_config(void);
190 static void read_config_file(void);
191 static void initplugins(void);
192 static int add_plugin(char *plugin_name);
193 static int remove_plugin(char *plugin_name);
194 static void plugins_done(void);
195 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
196 static tunnelidt new_tunnel(void);
197 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
198
199 // on slaves, alow BGP to withdraw cleanly before exiting
200 #define QUIT_DELAY 5
201
202 // quit actions (master)
203 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
204 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
205
206 // return internal time (10ths since process startup), set f if given
207 static clockt now(double *f)
208 {
209 struct timeval t;
210 gettimeofday(&t, 0);
211 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
212 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
213 }
214
215 // work out a retry time based on try number
216 // This is a straight bounded exponential backoff.
217 // Maximum re-try time is 32 seconds. (2^5).
218 clockt backoff(uint8_t try)
219 {
220 if (try > 5) try = 5; // max backoff
221 return now(NULL) + 10 * (1 << try);
222 }
223
224
225 //
226 // Log a debug message. Typically called via the LOG macro
227 //
228 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
229 {
230 static char message[65536] = {0};
231 va_list ap;
232
233 #ifdef RINGBUFFER
234 if (ringbuffer)
235 {
236 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
237 ringbuffer->tail = 0;
238 if (ringbuffer->tail == ringbuffer->head)
239 if (++ringbuffer->head >= RINGBUFFER_SIZE)
240 ringbuffer->head = 0;
241
242 ringbuffer->buffer[ringbuffer->tail].level = level;
243 ringbuffer->buffer[ringbuffer->tail].session = s;
244 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
245 va_start(ap, format);
246 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
247 va_end(ap);
248 }
249 #endif
250
251 if (config->debug < level) return;
252
253 va_start(ap, format);
254 vsnprintf(message, sizeof(message), format, ap);
255
256 if (log_stream)
257 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
258 else if (syslog_log)
259 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
260
261 va_end(ap);
262 }
263
264 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
265 {
266 int i, j;
267 const uint8_t *d = data;
268
269 if (config->debug < level) return;
270
271 // No support for _log_hex to syslog
272 if (log_stream)
273 {
274 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
275 setvbuf(log_stream, NULL, _IOFBF, 16384);
276
277 for (i = 0; i < maxsize; )
278 {
279 fprintf(log_stream, "%4X: ", i);
280 for (j = i; j < maxsize && j < (i + 16); j++)
281 {
282 fprintf(log_stream, "%02X ", d[j]);
283 if (j == i + 7)
284 fputs(": ", log_stream);
285 }
286
287 for (; j < i + 16; j++)
288 {
289 fputs(" ", log_stream);
290 if (j == i + 7)
291 fputs(": ", log_stream);
292 }
293
294 fputs(" ", log_stream);
295 for (j = i; j < maxsize && j < (i + 16); j++)
296 {
297 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
298 fputc(d[j], log_stream);
299 else
300 fputc('.', log_stream);
301
302 if (j == i + 7)
303 fputs(" ", log_stream);
304 }
305
306 i = j;
307 fputs("\n", log_stream);
308 }
309
310 fflush(log_stream);
311 setbuf(log_stream, NULL);
312 }
313 }
314
315 // update a counter, accumulating 2^32 wraps
316 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
317 {
318 uint32_t new = *counter + delta;
319 if (new < *counter)
320 (*wrap)++;
321
322 *counter = new;
323 }
324
325 // initialise the random generator
326 static void initrandom(char *source)
327 {
328 static char path[sizeof(config->random_device)] = "*undefined*";
329
330 // reinitialise only if we are forced to do so or if the config has changed
331 if (source && !strncmp(path, source, sizeof(path)))
332 return;
333
334 // close previous source, if any
335 if (rand_fd >= 0)
336 close(rand_fd);
337
338 rand_fd = -1;
339
340 if (source)
341 {
342 // register changes
343 snprintf(path, sizeof(path), "%s", source);
344
345 if (*path == '/')
346 {
347 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
348 if (rand_fd < 0)
349 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
350 path, strerror(errno));
351 }
352 }
353 }
354
355 // fill buffer with random data
356 void random_data(uint8_t *buf, int len)
357 {
358 int n = 0;
359
360 CSTAT(random_data);
361 if (rand_fd >= 0)
362 {
363 n = read(rand_fd, buf, len);
364 if (n >= len) return;
365 if (n < 0)
366 {
367 if (errno != EAGAIN)
368 {
369 LOG(0, 0, 0, "Error reading from random source: %s\n",
370 strerror(errno));
371
372 // fall back to rand()
373 initrandom(NULL);
374 }
375
376 n = 0;
377 }
378 }
379
380 // append missing data
381 while (n < len)
382 // not using the low order bits from the prng stream
383 buf[n++] = (rand() >> 4) & 0xff;
384 }
385
386 // Add a route
387 //
388 // This adds it to the routing table, advertises it
389 // via BGP if enabled, and stuffs it into the
390 // 'sessionbyip' cache.
391 //
392 // 'ip' and 'mask' must be in _host_ order.
393 //
394 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
395 {
396 struct rtentry r;
397 int i;
398
399 if (!mask) mask = 0xffffffff;
400
401 ip &= mask; // Force the ip to be the first one in the route.
402
403 memset(&r, 0, sizeof(r));
404 r.rt_dev = config->tundevice;
405 r.rt_dst.sa_family = AF_INET;
406 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
407 r.rt_gateway.sa_family = AF_INET;
408 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
409 r.rt_genmask.sa_family = AF_INET;
410 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
411 r.rt_flags = (RTF_UP | RTF_STATIC);
412 if (gw)
413 r.rt_flags |= RTF_GATEWAY;
414 else if (mask == 0xffffffff)
415 r.rt_flags |= RTF_HOST;
416
417 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
418 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
419 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
420
421 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
422 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
423
424 #ifdef BGP
425 if (add)
426 bgp_add_route(htonl(ip), htonl(mask));
427 else
428 bgp_del_route(htonl(ip), htonl(mask));
429 #endif /* BGP */
430
431 // Add/Remove the IPs to the 'sessionbyip' cache.
432 // Note that we add the zero address in the case of
433 // a network route. Roll on CIDR.
434
435 // Note that 's == 0' implies this is the address pool.
436 // We still cache it here, because it will pre-fill
437 // the malloc'ed tree.
438
439 if (s)
440 {
441 if (!add) // Are we deleting a route?
442 s = 0; // Caching the session as '0' is the same as uncaching.
443
444 for (i = ip; (i&mask) == (ip&mask) ; ++i)
445 cache_ipmap(i, s);
446 }
447 }
448
449 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
450 {
451 struct in6_rtmsg rt;
452 char ipv6addr[INET6_ADDRSTRLEN];
453
454 if (ifr6fd < 0)
455 {
456 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
457 return;
458 }
459
460 memset(&rt, 0, sizeof(rt));
461
462 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
463 rt.rtmsg_dst_len = prefixlen;
464 rt.rtmsg_metric = 1;
465 rt.rtmsg_flags = RTF_UP;
466 rt.rtmsg_ifindex = tunidx;
467
468 LOG(1, 0, 0, "Route %s %s/%d\n",
469 add ? "add" : "del",
470 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
471 prefixlen);
472
473 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
474 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
475 strerror(errno));
476
477 // FIXME: need to add BGP routing (RFC2858)
478
479 if (s)
480 {
481 if (!add) // Are we deleting a route?
482 s = 0; // Caching the session as '0' is the same as uncaching.
483
484 cache_ipv6map(ip, prefixlen, s);
485 }
486
487 return;
488 }
489
490 // defined in linux/ipv6.h, but tricky to include from user-space
491 // TODO: move routing to use netlink rather than ioctl
492 struct in6_ifreq {
493 struct in6_addr ifr6_addr;
494 __u32 ifr6_prefixlen;
495 unsigned int ifr6_ifindex;
496 };
497
498 //
499 // Set up TUN interface
500 static void inittun(void)
501 {
502 struct ifreq ifr;
503 struct in6_ifreq ifr6;
504 struct sockaddr_in sin = {0};
505 memset(&ifr, 0, sizeof(ifr));
506 ifr.ifr_flags = IFF_TUN;
507
508 tunfd = open(TUNDEVICE, O_RDWR);
509 if (tunfd < 0)
510 { // fatal
511 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
512 exit(1);
513 }
514 {
515 int flags = fcntl(tunfd, F_GETFL, 0);
516 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
517 }
518 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
519 {
520 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
521 exit(1);
522 }
523 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
524 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
525 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
526
527 sin.sin_family = AF_INET;
528 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
529 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
530
531 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
532 {
533 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
534 exit(1);
535 }
536 /* Bump up the qlen to deal with bursts from the network */
537 ifr.ifr_qlen = 1000;
538 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
539 {
540 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
541 exit(1);
542 }
543 ifr.ifr_flags = IFF_UP;
544 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
545 {
546 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
547 exit(1);
548 }
549 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
550 {
551 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
552 exit(1);
553 }
554 tunidx = ifr.ifr_ifindex;
555
556 // Only setup IPv6 on the tun device if we have a configured prefix
557 if (config->ipv6_prefix.s6_addr[0]) {
558 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
559
560 // Link local address is FE80::1
561 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
562 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
563 ifr6.ifr6_addr.s6_addr[1] = 0x80;
564 ifr6.ifr6_addr.s6_addr[15] = 1;
565 ifr6.ifr6_prefixlen = 64;
566 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
567 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
568 {
569 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
570 " %s\n", strerror(errno));
571 }
572
573 // Global address is prefix::1
574 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
575 ifr6.ifr6_addr = config->ipv6_prefix;
576 ifr6.ifr6_addr.s6_addr[15] = 1;
577 ifr6.ifr6_prefixlen = 64;
578 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
579 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
580 {
581 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
582 strerror(errno));
583 }
584 }
585 }
586
587 // set up UDP ports
588 static void initudp(void)
589 {
590 int on = 1;
591 struct sockaddr_in addr;
592
593 // Tunnel
594 memset(&addr, 0, sizeof(addr));
595 addr.sin_family = AF_INET;
596 addr.sin_port = htons(L2TPPORT);
597 addr.sin_addr.s_addr = config->bind_address;
598 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
599 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
600 {
601 int flags = fcntl(udpfd, F_GETFL, 0);
602 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
603 }
604 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
605 {
606 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
607 exit(1);
608 }
609
610 // Control
611 memset(&addr, 0, sizeof(addr));
612 addr.sin_family = AF_INET;
613 addr.sin_port = htons(NSCTL_PORT);
614 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
615 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
616 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
617 {
618 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
619 exit(1);
620 }
621
622 // Dynamic Authorization Extensions to RADIUS
623 memset(&addr, 0, sizeof(addr));
624 addr.sin_family = AF_INET;
625 addr.sin_port = htons(config->radius_dae_port);
626 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
627 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
628 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
629 {
630 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
631 exit(1);
632 }
633
634 // Intercept
635 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
636 }
637
638 //
639 // Find session by IP, < 1 for not found
640 //
641 // Confusingly enough, this 'ip' must be
642 // in _network_ order. This being the common
643 // case when looking it up from IP packet headers.
644 //
645 // We actually use this cache for two things.
646 // #1. For used IP addresses, this maps to the
647 // session ID that it's used by.
648 // #2. For un-used IP addresses, this maps to the
649 // index into the pool table that contains that
650 // IP address.
651 //
652
653 static int lookup_ipmap(in_addr_t ip)
654 {
655 uint8_t *a = (uint8_t *) &ip;
656 uint8_t **d = (uint8_t **) ip_hash;
657
658 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
659 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
660 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
661
662 return (int) (intptr_t) d[(size_t) *a];
663 }
664
665 static int lookup_ipv6map(struct in6_addr ip)
666 {
667 struct ipv6radix *curnode;
668 int i;
669 int s;
670 char ipv6addr[INET6_ADDRSTRLEN];
671
672 curnode = &ipv6_hash[ip.s6_addr[0]];
673 i = 1;
674 s = curnode->sess;
675
676 while (s == 0 && i < 15 && curnode->branch != NULL)
677 {
678 curnode = &curnode->branch[ip.s6_addr[i]];
679 s = curnode->sess;
680 i++;
681 }
682
683 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
684 inet_ntop(AF_INET6, &ip, ipv6addr,
685 INET6_ADDRSTRLEN),
686 s);
687
688 return s;
689 }
690
691 sessionidt sessionbyip(in_addr_t ip)
692 {
693 int s = lookup_ipmap(ip);
694 CSTAT(sessionbyip);
695
696 if (s > 0 && s < MAXSESSION && session[s].opened)
697 return (sessionidt) s;
698
699 return 0;
700 }
701
702 sessionidt sessionbyipv6(struct in6_addr ip)
703 {
704 int s;
705 CSTAT(sessionbyipv6);
706
707 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
708 (ip.s6_addr[0] == 0xFE &&
709 ip.s6_addr[1] == 0x80 &&
710 ip.s6_addr16[1] == 0 &&
711 ip.s6_addr16[2] == 0 &&
712 ip.s6_addr16[3] == 0)) {
713 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
714 } else {
715 s = lookup_ipv6map(ip);
716 }
717
718 if (s > 0 && s < MAXSESSION && session[s].opened)
719 return s;
720
721 return 0;
722 }
723
724 //
725 // Take an IP address in HOST byte order and
726 // add it to the sessionid by IP cache.
727 //
728 // (It's actually cached in network order)
729 //
730 static void cache_ipmap(in_addr_t ip, int s)
731 {
732 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
733 uint8_t *a = (uint8_t *) &nip;
734 uint8_t **d = (uint8_t **) ip_hash;
735 int i;
736
737 for (i = 0; i < 3; i++)
738 {
739 if (!d[(size_t) a[i]])
740 {
741 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
742 return;
743 }
744
745 d = (uint8_t **) d[(size_t) a[i]];
746 }
747
748 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
749
750 if (s > 0)
751 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
752
753 else if (s == 0)
754 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
755 // else a map to an ip pool index.
756 }
757
758 static void uncache_ipmap(in_addr_t ip)
759 {
760 cache_ipmap(ip, 0); // Assign it to the NULL session.
761 }
762
763 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
764 {
765 int i;
766 int bytes;
767 struct ipv6radix *curnode;
768 char ipv6addr[INET6_ADDRSTRLEN];
769
770 curnode = &ipv6_hash[ip.s6_addr[0]];
771
772 bytes = prefixlen >> 3;
773 i = 1;
774 while (i < bytes) {
775 if (curnode->branch == NULL)
776 {
777 if (!(curnode->branch = calloc(256,
778 sizeof (struct ipv6radix))))
779 return;
780 }
781 curnode = &curnode->branch[ip.s6_addr[i]];
782 i++;
783 }
784
785 curnode->sess = s;
786
787 if (s > 0)
788 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
789 inet_ntop(AF_INET6, &ip, ipv6addr,
790 INET6_ADDRSTRLEN),
791 prefixlen);
792 else if (s == 0)
793 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
794 inet_ntop(AF_INET6, &ip, ipv6addr,
795 INET6_ADDRSTRLEN),
796 prefixlen);
797 }
798
799 //
800 // CLI list to dump current ipcache.
801 //
802 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
803 {
804 char **d = (char **) ip_hash, **e, **f, **g;
805 int i, j, k, l;
806 int count = 0;
807
808 if (CLI_HELP_REQUESTED)
809 return CLI_HELP_NO_ARGS;
810
811 cli_print(cli, "%7s %s", "Sess#", "IP Address");
812
813 for (i = 0; i < 256; ++i)
814 {
815 if (!d[i])
816 continue;
817 e = (char **) d[i];
818 for (j = 0; j < 256; ++j)
819 {
820 if (!e[j])
821 continue;
822 f = (char **) e[j];
823 for (k = 0; k < 256; ++k)
824 {
825 if (!f[k])
826 continue;
827 g = (char **)f[k];
828 for (l = 0; l < 256; ++l)
829 {
830 if (!g[l])
831 continue;
832 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
833 ++count;
834 }
835 }
836 }
837 }
838 cli_print(cli, "%d entries in cache", count);
839 return CLI_OK;
840 }
841
842
843 // Find session by username, 0 for not found
844 // walled garden users aren't authenticated, so the username is
845 // reasonably useless. Ignore them to avoid incorrect actions
846 //
847 // This is VERY inefficent. Don't call it often. :)
848 //
849 sessionidt sessionbyuser(char *username)
850 {
851 int s;
852 CSTAT(sessionbyuser);
853
854 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
855 {
856 if (!session[s].opened)
857 continue;
858
859 if (session[s].walled_garden)
860 continue; // Skip walled garden users.
861
862 if (!strncmp(session[s].user, username, 128))
863 return s;
864
865 }
866 return 0; // Not found.
867 }
868
869 void send_garp(in_addr_t ip)
870 {
871 int s;
872 struct ifreq ifr;
873 uint8_t mac[6];
874
875 s = socket(PF_INET, SOCK_DGRAM, 0);
876 if (s < 0)
877 {
878 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
879 return;
880 }
881 memset(&ifr, 0, sizeof(ifr));
882 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
883 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
884 {
885 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
886 close(s);
887 return;
888 }
889 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
890 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
891 {
892 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
893 close(s);
894 return;
895 }
896 close(s);
897 sendarp(ifr.ifr_ifindex, mac, ip);
898 }
899
900 static sessiont *sessiontbysessionidt(sessionidt s)
901 {
902 if (!s || s >= MAXSESSION) return NULL;
903 return &session[s];
904 }
905
906 static sessionidt sessionidtbysessiont(sessiont *s)
907 {
908 sessionidt val = s-session;
909 if (s < session || val >= MAXSESSION) return 0;
910 return val;
911 }
912
913 // actually send a control message for a specific tunnel
914 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
915 {
916 struct sockaddr_in addr;
917
918 CSTAT(tunnelsend);
919
920 if (!t)
921 {
922 static int backtrace_count = 0;
923 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
924 STAT(tunnel_tx_errors);
925 log_backtrace(backtrace_count, 5)
926 return;
927 }
928
929 if (!tunnel[t].ip)
930 {
931 static int backtrace_count = 0;
932 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
933 log_backtrace(backtrace_count, 5)
934 STAT(tunnel_tx_errors);
935 return;
936 }
937
938 memset(&addr, 0, sizeof(addr));
939 addr.sin_family = AF_INET;
940 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
941 addr.sin_port = htons(tunnel[t].port);
942
943 // sequence expected, if sequence in message
944 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
945
946 // If this is a control message, deal with retries
947 if (*buf & 0x80)
948 {
949 tunnel[t].last = time_now; // control message sent
950 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
951 if (tunnel[t].try > 1)
952 {
953 STAT(tunnel_retries);
954 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
955 }
956 }
957
958 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
959 {
960 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
961 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
962 STAT(tunnel_tx_errors);
963 return;
964 }
965
966 LOG_HEX(5, "Send Tunnel Data", buf, l);
967 STAT(tunnel_tx_packets);
968 INC_STAT(tunnel_tx_bytes, l);
969 }
970
971 //
972 // Tiny helper function to write data to
973 // the 'tun' device.
974 //
975 int tun_write(uint8_t * data, int size)
976 {
977 return write(tunfd, data, size);
978 }
979
980 // process outgoing (to tunnel) IP
981 //
982 static void processipout(uint8_t *buf, int len)
983 {
984 sessionidt s;
985 sessiont *sp;
986 tunnelidt t;
987 in_addr_t ip;
988
989 uint8_t *data = buf; // Keep a copy of the originals.
990 int size = len;
991
992 uint8_t b[MAXETHER + 20];
993
994 CSTAT(processipout);
995
996 if (len < MIN_IP_SIZE)
997 {
998 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
999 STAT(tun_rx_errors);
1000 return;
1001 }
1002 if (len >= MAXETHER)
1003 {
1004 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1005 STAT(tun_rx_errors);
1006 return;
1007 }
1008
1009 // Skip the tun header
1010 buf += 4;
1011 len -= 4;
1012
1013 // Got an IP header now
1014 if (*(uint8_t *)(buf) >> 4 != 4)
1015 {
1016 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1017 return;
1018 }
1019
1020 ip = *(uint32_t *)(buf + 16);
1021 if (!(s = sessionbyip(ip)))
1022 {
1023 // Is this a packet for a session that doesn't exist?
1024 static int rate = 0; // Number of ICMP packets we've sent this second.
1025 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1026
1027 if (last != time_now)
1028 {
1029 last = time_now;
1030 rate = 0;
1031 }
1032
1033 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1034 {
1035 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1036 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1037 config->bind_address ? config->bind_address : my_address, buf, len);
1038 }
1039 return;
1040 }
1041 t = session[s].tunnel;
1042 sp = &session[s];
1043
1044 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1045 if (config->max_packets > 0)
1046 {
1047 if (sess_local[s].last_packet_out == TIME)
1048 {
1049 int max = config->max_packets;
1050
1051 // All packets for throttled sessions are handled by the
1052 // master, so further limit by using the throttle rate.
1053 // A bit of a kludge, since throttle rate is in kbps,
1054 // but should still be generous given our average DSL
1055 // packet size is 200 bytes: a limit of 28kbps equates
1056 // to around 180 packets per second.
1057 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1058 max = sp->throttle_out;
1059
1060 if (++sess_local[s].packets_out > max)
1061 {
1062 sess_local[s].packets_dropped++;
1063 return;
1064 }
1065 }
1066 else
1067 {
1068 if (sess_local[s].packets_dropped)
1069 {
1070 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1071 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1072 sess_local[s].packets_dropped, sess_local[s].packets_out,
1073 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1074 sp->user);
1075 }
1076
1077 sess_local[s].last_packet_out = TIME;
1078 sess_local[s].packets_out = 1;
1079 sess_local[s].packets_dropped = 0;
1080 }
1081 }
1082
1083 // run access-list if any
1084 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1085 return;
1086
1087 if (sp->tbf_out)
1088 {
1089 // Are we throttling this session?
1090 if (config->cluster_iam_master)
1091 tbf_queue_packet(sp->tbf_out, data, size);
1092 else
1093 master_throttle_packet(sp->tbf_out, data, size);
1094 return;
1095 }
1096 else if (sp->walled_garden && !config->cluster_iam_master)
1097 {
1098 // We are walled-gardening this
1099 master_garden_packet(s, data, size);
1100 return;
1101 }
1102
1103 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1104
1105 // Add on L2TP header
1106 {
1107 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1108 if (!p) return;
1109 tunnelsend(b, len + (p-b), t); // send it...
1110 }
1111
1112 // Snooping this session, send it to intercept box
1113 if (sp->snoop_ip && sp->snoop_port)
1114 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1115
1116 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1117 sp->cout_delta += len;
1118 sp->pout++;
1119 udp_tx += len;
1120
1121 sess_local[s].cout += len; // To send to master..
1122 sess_local[s].pout++;
1123 }
1124
1125 // process outgoing (to tunnel) IPv6
1126 //
1127 static void processipv6out(uint8_t * buf, int len)
1128 {
1129 sessionidt s;
1130 sessiont *sp;
1131 tunnelidt t;
1132 in_addr_t ip;
1133 struct in6_addr ip6;
1134
1135 uint8_t *data = buf; // Keep a copy of the originals.
1136 int size = len;
1137
1138 uint8_t b[MAXETHER + 20];
1139
1140 CSTAT(processipv6out);
1141
1142 if (len < MIN_IP_SIZE)
1143 {
1144 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1145 STAT(tunnel_tx_errors);
1146 return;
1147 }
1148 if (len >= MAXETHER)
1149 {
1150 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1151 STAT(tunnel_tx_errors);
1152 return;
1153 }
1154
1155 // Skip the tun header
1156 buf += 4;
1157 len -= 4;
1158
1159 // Got an IP header now
1160 if (*(uint8_t *)(buf) >> 4 != 6)
1161 {
1162 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1163 return;
1164 }
1165
1166 ip6 = *(struct in6_addr *)(buf+24);
1167 s = sessionbyipv6(ip6);
1168
1169 if (s == 0)
1170 {
1171 ip = *(uint32_t *)(buf + 32);
1172 s = sessionbyip(ip);
1173 }
1174
1175 if (s == 0)
1176 {
1177 // Is this a packet for a session that doesn't exist?
1178 static int rate = 0; // Number of ICMP packets we've sent this second.
1179 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1180
1181 if (last != time_now)
1182 {
1183 last = time_now;
1184 rate = 0;
1185 }
1186
1187 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1188 {
1189 // FIXME: Should send icmp6 host unreachable
1190 }
1191 return;
1192 }
1193 t = session[s].tunnel;
1194 sp = &session[s];
1195
1196 // FIXME: add DoS prevention/filters?
1197
1198 if (sp->tbf_out)
1199 {
1200 // Are we throttling this session?
1201 if (config->cluster_iam_master)
1202 tbf_queue_packet(sp->tbf_out, data, size);
1203 else
1204 master_throttle_packet(sp->tbf_out, data, size);
1205 return;
1206 }
1207 else if (sp->walled_garden && !config->cluster_iam_master)
1208 {
1209 // We are walled-gardening this
1210 master_garden_packet(s, data, size);
1211 return;
1212 }
1213
1214 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1215
1216 // Add on L2TP header
1217 {
1218 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1219 if (!p) return;
1220 tunnelsend(b, len + (p-b), t); // send it...
1221 }
1222
1223 // Snooping this session, send it to intercept box
1224 if (sp->snoop_ip && sp->snoop_port)
1225 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1226
1227 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1228 sp->cout_delta += len;
1229 sp->pout++;
1230 udp_tx += len;
1231
1232 sess_local[s].cout += len; // To send to master..
1233 sess_local[s].pout++;
1234 }
1235
1236 //
1237 // Helper routine for the TBF filters.
1238 // Used to send queued data in to the user!
1239 //
1240 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1241 {
1242 sessiont *sp;
1243 tunnelidt t;
1244 in_addr_t ip;
1245
1246 uint8_t b[MAXETHER + 20];
1247
1248 if (len < 0 || len > MAXETHER)
1249 {
1250 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1251 return;
1252 }
1253
1254 // Skip the tun header
1255 buf += 4;
1256 len -= 4;
1257
1258 ip = *(in_addr_t *)(buf + 16);
1259
1260 if (!session[s].ip)
1261 return;
1262
1263 t = session[s].tunnel;
1264 sp = &session[s];
1265
1266 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1267
1268 // Add on L2TP header
1269 {
1270 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1271 if (!p) return;
1272 tunnelsend(b, len + (p-b), t); // send it...
1273 }
1274
1275 // Snooping this session.
1276 if (sp->snoop_ip && sp->snoop_port)
1277 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1278
1279 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1280 sp->cout_delta += len;
1281 sp->pout++;
1282 udp_tx += len;
1283
1284 sess_local[s].cout += len; // To send to master..
1285 sess_local[s].pout++;
1286 }
1287
1288 // add an AVP (16 bit)
1289 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1290 {
1291 uint16_t l = (m ? 0x8008 : 0x0008);
1292 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1293 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1294 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1295 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1296 c->length += 8;
1297 }
1298
1299 // add an AVP (32 bit)
1300 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1301 {
1302 uint16_t l = (m ? 0x800A : 0x000A);
1303 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1304 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1305 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1306 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1307 c->length += 10;
1308 }
1309
1310 // add an AVP (string)
1311 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1312 {
1313 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1314 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1315 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1316 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1317 memcpy(c->buf + c->length + 6, val, strlen(val));
1318 c->length += 6 + strlen(val);
1319 }
1320
1321 // add a binary AVP
1322 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1323 {
1324 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1325 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1326 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1327 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1328 memcpy(c->buf + c->length + 6, val, len);
1329 c->length += 6 + len;
1330 }
1331
1332 // new control connection
1333 static controlt *controlnew(uint16_t mtype)
1334 {
1335 controlt *c;
1336 if (!controlfree)
1337 c = malloc(sizeof(controlt));
1338 else
1339 {
1340 c = controlfree;
1341 controlfree = c->next;
1342 }
1343 assert(c);
1344 c->next = 0;
1345 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1346 c->length = 12;
1347 control16(c, 0, mtype, 1);
1348 return c;
1349 }
1350
1351 // send zero block if nothing is waiting
1352 // (ZLB send).
1353 static void controlnull(tunnelidt t)
1354 {
1355 uint8_t buf[12];
1356 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1357 return;
1358
1359 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1360 *(uint16_t *) (buf + 2) = htons(12); // length
1361 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1362 *(uint16_t *) (buf + 6) = htons(0); // session
1363 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1364 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1365 tunnelsend(buf, 12, t);
1366 }
1367
1368 // add a control message to a tunnel, and send if within window
1369 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1370 {
1371 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1372 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1373 *(uint16_t *) (c->buf + 6) = htons(far); // session
1374 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1375 tunnel[t].ns++; // advance sequence
1376 // link in message in to queue
1377 if (tunnel[t].controlc)
1378 tunnel[t].controle->next = c;
1379 else
1380 tunnel[t].controls = c;
1381
1382 tunnel[t].controle = c;
1383 tunnel[t].controlc++;
1384
1385 // send now if space in window
1386 if (tunnel[t].controlc <= tunnel[t].window)
1387 {
1388 tunnel[t].try = 0; // first send
1389 tunnelsend(c->buf, c->length, t);
1390 }
1391 }
1392
1393 //
1394 // Throttle or Unthrottle a session
1395 //
1396 // Throttle the data from/to through a session to no more than
1397 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1398 // user).
1399 //
1400 // If either value is -1, the current value is retained for that
1401 // direction.
1402 //
1403 void throttle_session(sessionidt s, int rate_in, int rate_out)
1404 {
1405 if (!session[s].opened)
1406 return; // No-one home.
1407
1408 if (!*session[s].user)
1409 return; // User not logged in
1410
1411 if (rate_in >= 0)
1412 {
1413 int bytes = rate_in * 1024 / 8; // kbits to bytes
1414 if (session[s].tbf_in)
1415 free_tbf(session[s].tbf_in);
1416
1417 if (rate_in > 0)
1418 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1419 else
1420 session[s].tbf_in = 0;
1421
1422 session[s].throttle_in = rate_in;
1423 }
1424
1425 if (rate_out >= 0)
1426 {
1427 int bytes = rate_out * 1024 / 8;
1428 if (session[s].tbf_out)
1429 free_tbf(session[s].tbf_out);
1430
1431 if (rate_out > 0)
1432 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1433 else
1434 session[s].tbf_out = 0;
1435
1436 session[s].throttle_out = rate_out;
1437 }
1438 }
1439
1440 // add/remove filters from session (-1 = no change)
1441 void filter_session(sessionidt s, int filter_in, int filter_out)
1442 {
1443 if (!session[s].opened)
1444 return; // No-one home.
1445
1446 if (!*session[s].user)
1447 return; // User not logged in
1448
1449 // paranoia
1450 if (filter_in > MAXFILTER) filter_in = -1;
1451 if (filter_out > MAXFILTER) filter_out = -1;
1452 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1453 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1454
1455 if (filter_in >= 0)
1456 {
1457 if (session[s].filter_in)
1458 ip_filters[session[s].filter_in - 1].used--;
1459
1460 if (filter_in > 0)
1461 ip_filters[filter_in - 1].used++;
1462
1463 session[s].filter_in = filter_in;
1464 }
1465
1466 if (filter_out >= 0)
1467 {
1468 if (session[s].filter_out)
1469 ip_filters[session[s].filter_out - 1].used--;
1470
1471 if (filter_out > 0)
1472 ip_filters[filter_out - 1].used++;
1473
1474 session[s].filter_out = filter_out;
1475 }
1476 }
1477
1478 // start tidy shutdown of session
1479 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1480 {
1481 int walled_garden = session[s].walled_garden;
1482
1483
1484 CSTAT(sessionshutdown);
1485
1486 if (!session[s].opened)
1487 {
1488 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1489 return; // not a live session
1490 }
1491
1492 if (!session[s].die)
1493 {
1494 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1495 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1496 run_plugins(PLUGIN_KILL_SESSION, &data);
1497 }
1498
1499 if (session[s].ip && !walled_garden && !session[s].die)
1500 {
1501 // RADIUS Stop message
1502 uint16_t r = radiusnew(s);
1503 if (r)
1504 {
1505 // stop, if not already trying
1506 if (radius[r].state != RADIUSSTOP)
1507 radiussend(r, RADIUSSTOP);
1508 }
1509 else
1510 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1511
1512 // Save counters to dump to accounting file
1513 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1514 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1515 }
1516
1517 if (session[s].ip)
1518 { // IP allocated, clear and unroute
1519 int r;
1520 int routed = 0;
1521 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1522 {
1523 if ((session[s].ip & session[s].route[r].mask) ==
1524 (session[s].route[r].ip & session[s].route[r].mask))
1525 routed++;
1526
1527 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1528 session[s].route[r].ip = 0;
1529 }
1530
1531 if (session[s].ip_pool_index == -1) // static ip
1532 {
1533 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1534 session[s].ip = 0;
1535 }
1536 else
1537 free_ip_address(s);
1538
1539 // unroute IPv6, if setup
1540 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1541 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1542 }
1543
1544 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1545 throttle_session(s, 0, 0);
1546
1547 if (result)
1548 { // Send CDN
1549 controlt *c = controlnew(14); // sending CDN
1550 if (error)
1551 {
1552 uint8_t buf[4];
1553 *(uint16_t *) buf = htons(result);
1554 *(uint16_t *) (buf+2) = htons(error);
1555 controlb(c, 1, buf, 4, 1);
1556 }
1557 else
1558 control16(c, 1, result, 1);
1559
1560 control16(c, 14, s, 1); // assigned session (our end)
1561 controladd(c, session[s].far, session[s].tunnel); // send the message
1562 }
1563
1564 if (!session[s].die)
1565 session[s].die = TIME + 150; // Clean up in 15 seconds
1566
1567 // update filter refcounts
1568 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1569 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1570
1571 // clear PPP state
1572 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1573 sess_local[s].lcp.restart = 0;
1574 sess_local[s].ipcp.restart = 0;
1575 sess_local[s].ipv6cp.restart = 0;
1576 sess_local[s].ccp.restart = 0;
1577
1578 cluster_send_session(s);
1579 }
1580
1581 void sendipcp(sessionidt s, tunnelidt t)
1582 {
1583 uint8_t buf[MAXCONTROL];
1584 uint8_t *q;
1585
1586 CSTAT(sendipcp);
1587 LOG(3, s, t, "IPCP: send ConfigReq\n");
1588
1589 if (!session[s].unique_id)
1590 {
1591 if (!++last_id) ++last_id; // skip zero
1592 session[s].unique_id = last_id;
1593 }
1594
1595 q = makeppp(buf,sizeof(buf), 0, 0, s, t, PPPIPCP);
1596 if (!q) return;
1597
1598 *q = ConfigReq;
1599 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1600 *(uint16_t *) (q + 2) = htons(10); // packet length
1601 q[4] = 3; // ip address option
1602 q[5] = 6; // option length
1603 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1604 config->bind_address ? config->bind_address :
1605 my_address; // send my IP
1606
1607 tunnelsend(buf, 10 + (q - buf), t); // send it
1608 }
1609
1610 void sendipv6cp(sessionidt s, tunnelidt t)
1611 {
1612 uint8_t buf[MAXCONTROL];
1613 uint8_t *q;
1614
1615 CSTAT(sendipv6cp);
1616 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1617
1618 q = makeppp(buf,sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1619 if (!q) return;
1620
1621 *q = ConfigReq;
1622 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1623 // only send one type
1624 // of request
1625 *(uint16_t *) (q + 2) = htons(14);
1626 q[4] = 1; // interface identifier option
1627 q[5] = 10; // option length
1628 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1629 *(uint32_t *) (q + 10) = 0;
1630 q[13] = 1;
1631
1632 tunnelsend(buf, 14 + (q - buf), t); // send it
1633 }
1634
1635 static void sessionclear(sessionidt s)
1636 {
1637 memset(&session[s], 0, sizeof(session[s]));
1638 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1639 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1640
1641 session[s].tunnel = T_FREE; // Mark it as free.
1642 session[s].next = sessionfree;
1643 sessionfree = s;
1644 }
1645
1646 // kill a session now
1647 void sessionkill(sessionidt s, char *reason)
1648 {
1649
1650 CSTAT(sessionkill);
1651
1652 if (!session[s].opened) // not alive
1653 return;
1654
1655 if (session[s].next)
1656 {
1657 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1658 return;
1659 }
1660
1661 session[s].die = TIME;
1662 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1663 if (sess_local[s].radius)
1664 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1665
1666 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1667 sessionclear(s);
1668 cluster_send_session(s);
1669 }
1670
1671 static void tunnelclear(tunnelidt t)
1672 {
1673 if (!t) return;
1674 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1675 tunnel[t].state = TUNNELFREE;
1676 }
1677
1678 // kill a tunnel now
1679 static void tunnelkill(tunnelidt t, char *reason)
1680 {
1681 sessionidt s;
1682 controlt *c;
1683
1684 CSTAT(tunnelkill);
1685
1686 tunnel[t].state = TUNNELDIE;
1687
1688 // free control messages
1689 while ((c = tunnel[t].controls))
1690 {
1691 controlt * n = c->next;
1692 tunnel[t].controls = n;
1693 tunnel[t].controlc--;
1694 c->next = controlfree;
1695 controlfree = c;
1696 }
1697 // kill sessions
1698 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1699 if (session[s].tunnel == t)
1700 sessionkill(s, reason);
1701
1702 // free tunnel
1703 tunnelclear(t);
1704 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1705 cli_tunnel_actions[t].action = 0;
1706 cluster_send_tunnel(t);
1707 }
1708
1709 // shut down a tunnel cleanly
1710 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1711 {
1712 sessionidt s;
1713
1714 CSTAT(tunnelshutdown);
1715
1716 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1717 {
1718 // never set up, can immediately kill
1719 tunnelkill(t, reason);
1720 return;
1721 }
1722 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1723
1724 // close session
1725 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1726 if (session[s].tunnel == t)
1727 sessionshutdown(s, reason, 0, 0);
1728
1729 tunnel[t].state = TUNNELDIE;
1730 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1731 cluster_send_tunnel(t);
1732 // TBA - should we wait for sessions to stop?
1733 if (result)
1734 {
1735 controlt *c = controlnew(4); // sending StopCCN
1736 if (error)
1737 {
1738 uint8_t buf[64];
1739 int l = 4;
1740 *(uint16_t *) buf = htons(result);
1741 *(uint16_t *) (buf+2) = htons(error);
1742 if (msg)
1743 {
1744 int m = strlen(msg);
1745 if (m + 4 > sizeof(buf))
1746 m = sizeof(buf) - 4;
1747
1748 memcpy(buf+4, msg, m);
1749 l += m;
1750 }
1751
1752 controlb(c, 1, buf, l, 1);
1753 }
1754 else
1755 control16(c, 1, result, 1);
1756
1757 control16(c, 9, t, 1); // assigned tunnel (our end)
1758 controladd(c, 0, t); // send the message
1759 }
1760 }
1761
1762 // read and process packet on tunnel (UDP)
1763 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1764 {
1765 uint8_t *chapresponse = NULL;
1766 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1767 uint8_t *p = buf + 2;
1768
1769
1770 CSTAT(processudp);
1771
1772 udp_rx += len;
1773 udp_rx_pkt++;
1774 LOG_HEX(5, "UDP Data", buf, len);
1775 STAT(tunnel_rx_packets);
1776 INC_STAT(tunnel_rx_bytes, len);
1777 if (len < 6)
1778 {
1779 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1780 STAT(tunnel_rx_errors);
1781 return;
1782 }
1783 if ((buf[1] & 0x0F) != 2)
1784 {
1785 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1786 STAT(tunnel_rx_errors);
1787 return;
1788 }
1789 if (*buf & 0x40)
1790 { // length
1791 l = ntohs(*(uint16_t *) p);
1792 p += 2;
1793 }
1794 t = ntohs(*(uint16_t *) p);
1795 p += 2;
1796 s = ntohs(*(uint16_t *) p);
1797 p += 2;
1798 if (s >= MAXSESSION)
1799 {
1800 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1801 STAT(tunnel_rx_errors);
1802 return;
1803 }
1804 if (t >= MAXTUNNEL)
1805 {
1806 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1807 STAT(tunnel_rx_errors);
1808 return;
1809 }
1810 if (*buf & 0x08)
1811 { // ns/nr
1812 ns = ntohs(*(uint16_t *) p);
1813 p += 2;
1814 nr = ntohs(*(uint16_t *) p);
1815 p += 2;
1816 }
1817 if (*buf & 0x02)
1818 { // offset
1819 uint16_t o = ntohs(*(uint16_t *) p);
1820 p += o + 2;
1821 }
1822 if ((p - buf) > l)
1823 {
1824 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1825 STAT(tunnel_rx_errors);
1826 return;
1827 }
1828 l -= (p - buf);
1829 if (*buf & 0x80)
1830 { // control
1831 uint16_t message = 0xFFFF; // message type
1832 uint8_t fatal = 0;
1833 uint8_t mandatory = 0;
1834 uint16_t asession = 0; // assigned session
1835 uint32_t amagic = 0; // magic number
1836 uint8_t aflags = 0; // flags from last LCF
1837 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1838 char called[MAXTEL] = ""; // called number
1839 char calling[MAXTEL] = ""; // calling number
1840
1841 if (!config->cluster_iam_master)
1842 {
1843 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1844 return;
1845 }
1846
1847 // control messages must have bits 0x80|0x40|0x08
1848 // (type, length and sequence) set, and bits 0x02|0x01
1849 // (offset and priority) clear
1850 if ((*buf & 0xCB) != 0xC8)
1851 {
1852 LOG(1, s, t, "Bad control header %02X\n", *buf);
1853 STAT(tunnel_rx_errors);
1854 return;
1855 }
1856
1857 // check for duplicate tunnel open message
1858 if (!t && ns == 0)
1859 {
1860 int i;
1861
1862 //
1863 // Is this a duplicate of the first packet? (SCCRQ)
1864 //
1865 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1866 {
1867 if (tunnel[i].state != TUNNELOPENING ||
1868 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1869 tunnel[i].port != ntohs(addr->sin_port) )
1870 continue;
1871 t = i;
1872 LOG(3, s, t, "Duplicate SCCRQ?\n");
1873 break;
1874 }
1875 }
1876
1877 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1878 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1879
1880 // if no tunnel specified, assign one
1881 if (!t)
1882 {
1883 if (!(t = new_tunnel()))
1884 {
1885 LOG(1, 0, 0, "No more tunnels\n");
1886 STAT(tunnel_overflow);
1887 return;
1888 }
1889 tunnelclear(t);
1890 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1891 tunnel[t].port = ntohs(addr->sin_port);
1892 tunnel[t].window = 4; // default window
1893 STAT(tunnel_created);
1894 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1895 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1896 }
1897
1898 // If the 'ns' just received is not the 'nr' we're
1899 // expecting, just send an ack and drop it.
1900 //
1901 // if 'ns' is less, then we got a retransmitted packet.
1902 // if 'ns' is greater than missed a packet. Either way
1903 // we should ignore it.
1904 if (ns != tunnel[t].nr)
1905 {
1906 // is this the sequence we were expecting?
1907 STAT(tunnel_rx_errors);
1908 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1909 t, ns, tunnel[t].nr);
1910
1911 if (l) // Is this not a ZLB?
1912 controlnull(t);
1913 return;
1914 }
1915
1916 // This is used to time out old tunnels
1917 tunnel[t].lastrec = time_now;
1918
1919 // check sequence of this message
1920 {
1921 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1922 // some to clear maybe?
1923 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1924 {
1925 controlt *c = tunnel[t].controls;
1926 tunnel[t].controls = c->next;
1927 tunnel[t].controlc--;
1928 c->next = controlfree;
1929 controlfree = c;
1930 skip--;
1931 tunnel[t].try = 0; // we have progress
1932 }
1933
1934 // receiver advance (do here so quoted correctly in any sends below)
1935 if (l) tunnel[t].nr = (ns + 1);
1936 if (skip < 0) skip = 0;
1937 if (skip < tunnel[t].controlc)
1938 {
1939 // some control packets can now be sent that were previous stuck out of window
1940 int tosend = tunnel[t].window - skip;
1941 controlt *c = tunnel[t].controls;
1942 while (c && skip)
1943 {
1944 c = c->next;
1945 skip--;
1946 }
1947 while (c && tosend)
1948 {
1949 tunnel[t].try = 0; // first send
1950 tunnelsend(c->buf, c->length, t);
1951 c = c->next;
1952 tosend--;
1953 }
1954 }
1955 if (!tunnel[t].controlc)
1956 tunnel[t].retry = 0; // caught up
1957 }
1958 if (l)
1959 { // if not a null message
1960 int result = 0;
1961 int error = 0;
1962 char *msg = 0;
1963
1964 // process AVPs
1965 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1966 {
1967 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1968 uint8_t *b = p;
1969 uint8_t flags = *p;
1970 uint16_t mtype;
1971 if (n > l)
1972 {
1973 LOG(1, s, t, "Invalid length in AVP\n");
1974 STAT(tunnel_rx_errors);
1975 return;
1976 }
1977 p += n; // next
1978 l -= n;
1979 if (flags & 0x3C) // reserved bits, should be clear
1980 {
1981 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1982 fatal = flags;
1983 result = 2; // general error
1984 error = 3; // reserved field non-zero
1985 msg = 0;
1986 continue; // next
1987 }
1988 b += 2;
1989 if (*(uint16_t *) (b))
1990 {
1991 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1992 fatal = flags;
1993 result = 2; // general error
1994 error = 6; // generic vendor-specific error
1995 msg = "unsupported vendor-specific";
1996 continue; // next
1997 }
1998 b += 2;
1999 mtype = ntohs(*(uint16_t *) (b));
2000 b += 2;
2001 n -= 6;
2002
2003 if (flags & 0x40)
2004 {
2005 uint16_t orig_len;
2006
2007 // handle hidden AVPs
2008 if (!*config->l2tpsecret)
2009 {
2010 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2011 fatal = flags;
2012 result = 2; // general error
2013 error = 6; // generic vendor-specific error
2014 msg = "secret not specified";
2015 continue;
2016 }
2017 if (!session[s].random_vector_length)
2018 {
2019 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2020 fatal = flags;
2021 result = 2; // general error
2022 error = 6; // generic
2023 msg = "no random vector";
2024 continue;
2025 }
2026 if (n < 8)
2027 {
2028 LOG(2, s, t, "Short hidden AVP.\n");
2029 fatal = flags;
2030 result = 2; // general error
2031 error = 2; // length is wrong
2032 msg = 0;
2033 continue;
2034 }
2035
2036 // Unhide the AVP
2037 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2038
2039 orig_len = ntohs(*(uint16_t *) b);
2040 if (orig_len > n + 2)
2041 {
2042 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2043 orig_len, n);
2044
2045 fatal = flags;
2046 result = 2; // general error
2047 error = 2; // length is wrong
2048 msg = 0;
2049 continue;
2050 }
2051
2052 b += 2;
2053 n = orig_len;
2054 }
2055
2056 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2057 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2058
2059 switch (mtype)
2060 {
2061 case 0: // message type
2062 message = ntohs(*(uint16_t *) b);
2063 mandatory = flags & 0x80;
2064 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2065 break;
2066 case 1: // result code
2067 {
2068 uint16_t rescode = ntohs(*(uint16_t *) b);
2069 const char* resdesc = "(unknown)";
2070 if (message == 4)
2071 { /* StopCCN */
2072 resdesc = l2tp_stopccn_result_code(rescode);
2073 }
2074 else if (message == 14)
2075 { /* CDN */
2076 resdesc = l2tp_cdn_result_code(rescode);
2077 }
2078
2079 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2080 if (n >= 4)
2081 {
2082 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2083 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2084 }
2085 if (n > 4)
2086 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2087
2088 break;
2089 }
2090 break;
2091 case 2: // protocol version
2092 {
2093 version = ntohs(*(uint16_t *) (b));
2094 LOG(4, s, t, " Protocol version = %d\n", version);
2095 if (version && version != 0x0100)
2096 { // allow 0.0 and 1.0
2097 LOG(1, s, t, " Bad protocol version %04X\n", version);
2098 fatal = flags;
2099 result = 5; // unspported protocol version
2100 error = 0x0100; // supported version
2101 msg = 0;
2102 continue; // next
2103 }
2104 }
2105 break;
2106 case 3: // framing capabilities
2107 // LOG(4, s, t, "Framing capabilities\n");
2108 break;
2109 case 4: // bearer capabilities
2110 // LOG(4, s, t, "Bearer capabilities\n");
2111 break;
2112 case 5: // tie breaker
2113 // We never open tunnels, so we don't care about tie breakers
2114 // LOG(4, s, t, "Tie breaker\n");
2115 continue;
2116 case 6: // firmware revision
2117 // LOG(4, s, t, "Firmware revision\n");
2118 break;
2119 case 7: // host name
2120 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2121 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2122 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2123 // TBA - to send to RADIUS
2124 break;
2125 case 8: // vendor name
2126 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2127 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2128 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2129 break;
2130 case 9: // assigned tunnel
2131 tunnel[t].far = ntohs(*(uint16_t *) (b));
2132 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2133 break;
2134 case 10: // rx window
2135 tunnel[t].window = ntohs(*(uint16_t *) (b));
2136 if (!tunnel[t].window)
2137 tunnel[t].window = 1; // window of 0 is silly
2138 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2139 break;
2140 case 11: // Challenge
2141 {
2142 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2143 build_chap_response(b, 2, n, &chapresponse);
2144 }
2145 break;
2146 case 13: // Response
2147 // Why did they send a response? We never challenge.
2148 LOG(2, s, t, " received unexpected challenge response\n");
2149 break;
2150
2151 case 14: // assigned session
2152 asession = session[s].far = ntohs(*(uint16_t *) (b));
2153 LOG(4, s, t, " assigned session = %d\n", asession);
2154 break;
2155 case 15: // call serial number
2156 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2157 break;
2158 case 18: // bearer type
2159 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2160 // TBA - for RADIUS
2161 break;
2162 case 19: // framing type
2163 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2164 // TBA
2165 break;
2166 case 21: // called number
2167 memset(called, 0, sizeof(called));
2168 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2169 LOG(4, s, t, " Called <%s>\n", called);
2170 break;
2171 case 22: // calling number
2172 memset(calling, 0, sizeof(calling));
2173 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2174 LOG(4, s, t, " Calling <%s>\n", calling);
2175 break;
2176 case 23: // subtype
2177 break;
2178 case 24: // tx connect speed
2179 if (n == 4)
2180 {
2181 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2182 }
2183 else
2184 {
2185 // AS5300s send connect speed as a string
2186 char tmp[30];
2187 memset(tmp, 0, sizeof(tmp));
2188 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2189 session[s].tx_connect_speed = atol(tmp);
2190 }
2191 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2192 break;
2193 case 38: // rx connect speed
2194 if (n == 4)
2195 {
2196 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2197 }
2198 else
2199 {
2200 // AS5300s send connect speed as a string
2201 char tmp[30];
2202 memset(tmp, 0, sizeof(tmp));
2203 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2204 session[s].rx_connect_speed = atol(tmp);
2205 }
2206 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2207 break;
2208 case 25: // Physical Channel ID
2209 {
2210 uint32_t tmp = ntohl(*(uint32_t *) b);
2211 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2212 break;
2213 }
2214 case 29: // Proxy Authentication Type
2215 {
2216 uint16_t atype = ntohs(*(uint16_t *)b);
2217 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2218 break;
2219 }
2220 case 30: // Proxy Authentication Name
2221 {
2222 char authname[64];
2223 memset(authname, 0, sizeof(authname));
2224 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2225 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2226 authname);
2227 break;
2228 }
2229 case 31: // Proxy Authentication Challenge
2230 {
2231 LOG(4, s, t, " Proxy Auth Challenge\n");
2232 break;
2233 }
2234 case 32: // Proxy Authentication ID
2235 {
2236 uint16_t authid = ntohs(*(uint16_t *)(b));
2237 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2238 break;
2239 }
2240 case 33: // Proxy Authentication Response
2241 LOG(4, s, t, " Proxy Auth Response\n");
2242 break;
2243 case 27: // last sent lcp
2244 { // find magic number
2245 uint8_t *p = b, *e = p + n;
2246 while (p + 1 < e && p[1] && p + p[1] <= e)
2247 {
2248 if (*p == 5 && p[1] == 6) // Magic-Number
2249 amagic = ntohl(*(uint32_t *) (p + 2));
2250 else if (*p == 7) // Protocol-Field-Compression
2251 aflags |= SESSIONPFC;
2252 else if (*p == 8) // Address-and-Control-Field-Compression
2253 aflags |= SESSIONACFC;
2254 p += p[1];
2255 }
2256 }
2257 break;
2258 case 28: // last recv lcp confreq
2259 break;
2260 case 26: // Initial Received LCP CONFREQ
2261 break;
2262 case 39: // seq required - we control it as an LNS anyway...
2263 break;
2264 case 36: // Random Vector
2265 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2266 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2267 if (n > sizeof(session[s].random_vector))
2268 n = sizeof(session[s].random_vector);
2269 memcpy(session[s].random_vector, b, n);
2270 session[s].random_vector_length = n;
2271 break;
2272 default:
2273 {
2274 static char e[] = "unknown AVP 0xXXXX";
2275 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2276 fatal = flags;
2277 result = 2; // general error
2278 error = 8; // unknown mandatory AVP
2279 sprintf((msg = e) + 14, "%04x", mtype);
2280 continue; // next
2281 }
2282 }
2283 }
2284 // process message
2285 if (fatal & 0x80)
2286 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2287 else
2288 switch (message)
2289 {
2290 case 1: // SCCRQ - Start Control Connection Request
2291 tunnel[t].state = TUNNELOPENING;
2292 if (main_quit != QUIT_SHUTDOWN)
2293 {
2294 controlt *c = controlnew(2); // sending SCCRP
2295 control16(c, 2, version, 1); // protocol version
2296 control32(c, 3, 3, 1); // framing
2297 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2298 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2299 control16(c, 9, t, 1); // assigned tunnel
2300 controladd(c, 0, t); // send the resply
2301 }
2302 else
2303 {
2304 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2305 }
2306 break;
2307 case 2: // SCCRP
2308 tunnel[t].state = TUNNELOPEN;
2309 break;
2310 case 3: // SCCN
2311 tunnel[t].state = TUNNELOPEN;
2312 controlnull(t); // ack
2313 break;
2314 case 4: // StopCCN
2315 controlnull(t); // ack
2316 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2317 break;
2318 case 6: // HELLO
2319 controlnull(t); // simply ACK
2320 break;
2321 case 7: // OCRQ
2322 // TBA
2323 break;
2324 case 8: // OCRO
2325 // TBA
2326 break;
2327 case 9: // OCCN
2328 // TBA
2329 break;
2330 case 10: // ICRQ
2331 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2332 {
2333 controlt *c = controlnew(11); // ICRP
2334
2335 s = sessionfree;
2336 sessionfree = session[s].next;
2337 memset(&session[s], 0, sizeof(session[s]));
2338
2339 if (s > config->cluster_highest_sessionid)
2340 config->cluster_highest_sessionid = s;
2341
2342 session[s].opened = time_now;
2343 session[s].tunnel = t;
2344 session[s].far = asession;
2345 session[s].last_packet = time_now;
2346 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2347 control16(c, 14, s, 1); // assigned session
2348 controladd(c, asession, t); // send the reply
2349
2350 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2351 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2352
2353 session[s].ppp.phase = Establish;
2354 session[s].ppp.lcp = Starting;
2355
2356 STAT(session_created);
2357 break;
2358 }
2359
2360 {
2361 controlt *c = controlnew(14); // CDN
2362 if (!sessionfree)
2363 {
2364 STAT(session_overflow);
2365 LOG(1, 0, t, "No free sessions\n");
2366 control16(c, 1, 4, 0); // temporary lack of resources
2367 }
2368 else
2369 control16(c, 1, 2, 7); // shutting down, try another
2370
2371 controladd(c, asession, t); // send the message
2372 }
2373 return;
2374 case 11: // ICRP
2375 // TBA
2376 break;
2377 case 12: // ICCN
2378 if (amagic == 0) amagic = time_now;
2379 session[s].magic = amagic; // set magic number
2380 session[s].l2tp_flags = aflags; // set flags received
2381 session[s].mru = DEFAULT_MRU;
2382 controlnull(t); // ack
2383
2384 // start LCP
2385 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2386 sess_local[s].lcp.conf_sent = 1;
2387 sess_local[s].lcp.nak_sent = 0;
2388 sess_local[s].lcp_authtype = config->radius_authprefer;
2389 session[s].ppp.lcp = RequestSent;
2390 sendlcp(s, t);
2391
2392 break;
2393 case 14: // CDN
2394 controlnull(t); // ack
2395 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2396 break;
2397 case 0xFFFF:
2398 LOG(1, s, t, "Missing message type\n");
2399 break;
2400 default:
2401 STAT(tunnel_rx_errors);
2402 if (mandatory)
2403 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2404 else
2405 LOG(1, s, t, "Unknown message type %d\n", message);
2406 break;
2407 }
2408 if (chapresponse) free(chapresponse);
2409 cluster_send_tunnel(t);
2410 }
2411 else
2412 {
2413 LOG(4, s, t, " Got a ZLB ack\n");
2414 }
2415 }
2416 else
2417 { // data
2418 uint16_t prot;
2419
2420 LOG_HEX(5, "Receive Tunnel Data", p, l);
2421 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2422 { // HDLC address header, discard
2423 p += 2;
2424 l -= 2;
2425 }
2426 if (l < 2)
2427 {
2428 LOG(1, s, t, "Short ppp length %d\n", l);
2429 STAT(tunnel_rx_errors);
2430 return;
2431 }
2432 if (*p & 1)
2433 {
2434 prot = *p++;
2435 l--;
2436 }
2437 else
2438 {
2439 prot = ntohs(*(uint16_t *) p);
2440 p += 2;
2441 l -= 2;
2442 }
2443
2444 if (s && !session[s].opened) // Is something wrong??
2445 {
2446 if (!config->cluster_iam_master)
2447 {
2448 // Pass it off to the master to deal with..
2449 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2450 return;
2451 }
2452
2453
2454 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2455 STAT(tunnel_rx_errors);
2456 return;
2457 }
2458
2459 if (prot == PPPPAP)
2460 {
2461 session[s].last_packet = time_now;
2462 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2463 processpap(s, t, p, l);
2464 }
2465 else if (prot == PPPCHAP)
2466 {
2467 session[s].last_packet = time_now;
2468 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2469 processchap(s, t, p, l);
2470 }
2471 else if (prot == PPPLCP)
2472 {
2473 session[s].last_packet = time_now;
2474 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2475 processlcp(s, t, p, l);
2476 }
2477 else if (prot == PPPIPCP)
2478 {
2479 session[s].last_packet = time_now;
2480 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2481 processipcp(s, t, p, l);
2482 }
2483 else if (prot == PPPIPV6CP)
2484 {
2485 session[s].last_packet = time_now;
2486 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2487 processipv6cp(s, t, p, l);
2488 }
2489 else if (prot == PPPCCP)
2490 {
2491 session[s].last_packet = time_now;
2492 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2493 processccp(s, t, p, l);
2494 }
2495 else if (prot == PPPIP)
2496 {
2497 if (session[s].die)
2498 {
2499 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2500 return; // closing session, PPP not processed
2501 }
2502
2503 session[s].last_packet = time_now;
2504 if (session[s].walled_garden && !config->cluster_iam_master)
2505 {
2506 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2507 return;
2508 }
2509
2510 processipin(s, t, p, l);
2511 }
2512 else if (prot == PPPIPV6)
2513 {
2514 if (!config->ipv6_prefix.s6_addr[0])
2515 {
2516 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2517 return;
2518 }
2519 if (session[s].die)
2520 {
2521 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2522 return; // closing session, PPP not processed
2523 }
2524
2525 session[s].last_packet = time_now;
2526 if (session[s].walled_garden && !config->cluster_iam_master)
2527 {
2528 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2529 return;
2530 }
2531
2532 processipv6in(s, t, p, l);
2533 }
2534 else
2535 {
2536 STAT(tunnel_rx_errors);
2537 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2538 }
2539 }
2540 }
2541
2542 // read and process packet on tun
2543 static void processtun(uint8_t * buf, int len)
2544 {
2545 LOG_HEX(5, "Receive TUN Data", buf, len);
2546 STAT(tun_rx_packets);
2547 INC_STAT(tun_rx_bytes, len);
2548
2549 CSTAT(processtun);
2550
2551 eth_rx_pkt++;
2552 eth_rx += len;
2553 if (len < 22)
2554 {
2555 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2556 STAT(tun_rx_errors);
2557 return;
2558 }
2559
2560 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2561 processipout(buf, len);
2562 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2563 && config->ipv6_prefix.s6_addr[0])
2564 processipv6out(buf, len);
2565
2566 // Else discard.
2567 }
2568
2569 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2570 // that we look at the whole of the tunnel, radius and session tables
2571 // every second
2572 static void regular_cleanups(double period)
2573 {
2574 // Next tunnel, radius and session to check for actions on.
2575 static tunnelidt t = 0;
2576 static int r = 0;
2577 static sessionidt s = 0;
2578
2579 int t_actions = 0;
2580 int r_actions = 0;
2581 int s_actions = 0;
2582
2583 int t_slice;
2584 int r_slice;
2585 int s_slice;
2586
2587 int i;
2588 int a;
2589
2590 // divide up tables into slices based on the last run
2591 t_slice = config->cluster_highest_tunnelid * period;
2592 r_slice = (MAXRADIUS - 1) * period;
2593 s_slice = config->cluster_highest_sessionid * period;
2594
2595 if (t_slice < 1)
2596 t_slice = 1;
2597 else if (t_slice > config->cluster_highest_tunnelid)
2598 t_slice = config->cluster_highest_tunnelid;
2599
2600 if (r_slice < 1)
2601 r_slice = 1;
2602 else if (r_slice > (MAXRADIUS - 1))
2603 r_slice = MAXRADIUS - 1;
2604
2605 if (s_slice < 1)
2606 s_slice = 1;
2607 else if (s_slice > config->cluster_highest_sessionid)
2608 s_slice = config->cluster_highest_sessionid;
2609
2610 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2611
2612 for (i = 0; i < t_slice; i++)
2613 {
2614 t++;
2615 if (t > config->cluster_highest_tunnelid)
2616 t = 1;
2617
2618 // check for expired tunnels
2619 if (tunnel[t].die && tunnel[t].die <= TIME)
2620 {
2621 STAT(tunnel_timeout);
2622 tunnelkill(t, "Expired");
2623 t_actions++;
2624 continue;
2625 }
2626 // check for message resend
2627 if (tunnel[t].retry && tunnel[t].controlc)
2628 {
2629 // resend pending messages as timeout on reply
2630 if (tunnel[t].retry <= TIME)
2631 {
2632 controlt *c = tunnel[t].controls;
2633 uint8_t w = tunnel[t].window;
2634 tunnel[t].try++; // another try
2635 if (tunnel[t].try > 5)
2636 tunnelkill(t, "Timeout on control message"); // game over
2637 else
2638 while (c && w--)
2639 {
2640 tunnelsend(c->buf, c->length, t);
2641 c = c->next;
2642 }
2643
2644 t_actions++;
2645 }
2646 }
2647 // Send hello
2648 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2649 {
2650 controlt *c = controlnew(6); // sending HELLO
2651 controladd(c, 0, t); // send the message
2652 LOG(3, 0, t, "Sending HELLO message\n");
2653 t_actions++;
2654 }
2655
2656 // Check for tunnel changes requested from the CLI
2657 if ((a = cli_tunnel_actions[t].action))
2658 {
2659 cli_tunnel_actions[t].action = 0;
2660 if (a & CLI_TUN_KILL)
2661 {
2662 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2663 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2664 t_actions++;
2665 }
2666 }
2667 }
2668
2669 for (i = 0; i < r_slice; i++)
2670 {
2671 r++;
2672 if (r >= MAXRADIUS)
2673 r = 1;
2674
2675 if (!radius[r].state)
2676 continue;
2677
2678 if (radius[r].retry <= TIME)
2679 {
2680 radiusretry(r);
2681 r_actions++;
2682 }
2683 }
2684
2685 for (i = 0; i < s_slice; i++)
2686 {
2687 s++;
2688 if (s > config->cluster_highest_sessionid)
2689 s = 1;
2690
2691 if (!session[s].opened) // Session isn't in use
2692 continue;
2693
2694 // check for expired sessions
2695 if (session[s].die)
2696 {
2697 if (session[s].die <= TIME)
2698 {
2699 sessionkill(s, "Expired");
2700 s_actions++;
2701 }
2702 continue;
2703 }
2704
2705 // PPP timeouts
2706 if (sess_local[s].lcp.restart <= time_now)
2707 {
2708 int next_state = session[s].ppp.lcp;
2709 switch (session[s].ppp.lcp)
2710 {
2711 case RequestSent:
2712 case AckReceived:
2713 next_state = RequestSent;
2714
2715 case AckSent:
2716 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2717 {
2718 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2719 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2720 sess_local[s].lcp.conf_sent++;
2721 sendlcp(s, session[s].tunnel);
2722 change_state(s, lcp, next_state);
2723 }
2724 else
2725 {
2726 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2727 STAT(session_timeout);
2728 }
2729
2730 s_actions++;
2731 }
2732
2733 if (session[s].die)
2734 continue;
2735 }
2736
2737 if (sess_local[s].ipcp.restart <= time_now)
2738 {
2739 int next_state = session[s].ppp.ipcp;
2740 switch (session[s].ppp.ipcp)
2741 {
2742 case RequestSent:
2743 case AckReceived:
2744 next_state = RequestSent;
2745
2746 case AckSent:
2747 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2748 {
2749 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2750 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2751 sess_local[s].ipcp.conf_sent++;
2752 sendipcp(s, session[s].tunnel);
2753 change_state(s, ipcp, next_state);
2754 }
2755 else
2756 {
2757 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2758 STAT(session_timeout);
2759 }
2760
2761 s_actions++;
2762 }
2763
2764 if (session[s].die)
2765 continue;
2766 }
2767
2768 if (sess_local[s].ipv6cp.restart <= time_now)
2769 {
2770 int next_state = session[s].ppp.ipv6cp;
2771 switch (session[s].ppp.ipv6cp)
2772 {
2773 case RequestSent:
2774 case AckReceived:
2775 next_state = RequestSent;
2776
2777 case AckSent:
2778 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2779 {
2780 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2781 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2782 sess_local[s].ipv6cp.conf_sent++;
2783 sendipv6cp(s, session[s].tunnel);
2784 change_state(s, ipv6cp, next_state);
2785 }
2786 else
2787 {
2788 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2789 change_state(s, ipv6cp, Stopped);
2790 }
2791
2792 s_actions++;
2793 }
2794 }
2795
2796 if (sess_local[s].ccp.restart <= time_now)
2797 {
2798 int next_state = session[s].ppp.ccp;
2799 switch (session[s].ppp.ccp)
2800 {
2801 case RequestSent:
2802 case AckReceived:
2803 next_state = RequestSent;
2804
2805 case AckSent:
2806 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2807 {
2808 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2809 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2810 sess_local[s].ccp.conf_sent++;
2811 sendccp(s, session[s].tunnel);
2812 change_state(s, ccp, next_state);
2813 }
2814 else
2815 {
2816 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2817 change_state(s, ccp, Stopped);
2818 }
2819
2820 s_actions++;
2821 }
2822 }
2823
2824 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2825 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2826 {
2827 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2828 STAT(session_timeout);
2829 s_actions++;
2830 continue;
2831 }
2832
2833 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2834 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2835 {
2836 uint8_t b[MAXCONTROL] = {0};
2837
2838 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2839 if (!q) continue;
2840
2841 *q = EchoReq;
2842 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2843 *(uint16_t *)(q + 2) = htons(8); // Length
2844 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2845
2846 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2847 (int)(time_now - session[s].last_packet));
2848 tunnelsend(b, 24, session[s].tunnel); // send it
2849 s_actions++;
2850 }
2851
2852 // Check for actions requested from the CLI
2853 if ((a = cli_session_actions[s].action))
2854 {
2855 int send = 0;
2856
2857 cli_session_actions[s].action = 0;
2858 if (a & CLI_SESS_KILL)
2859 {
2860 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2861 sessionshutdown(s, "Requested by administrator.", 3, 0);
2862 a = 0; // dead, no need to check for other actions
2863 s_actions++;
2864 }
2865
2866 if (a & CLI_SESS_NOSNOOP)
2867 {
2868 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2869 session[s].snoop_ip = 0;
2870 session[s].snoop_port = 0;
2871 s_actions++;
2872 send++;
2873 }
2874 else if (a & CLI_SESS_SNOOP)
2875 {
2876 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2877 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2878 cli_session_actions[s].snoop_port);
2879
2880 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2881 session[s].snoop_port = cli_session_actions[s].snoop_port;
2882 s_actions++;
2883 send++;
2884 }
2885
2886 if (a & CLI_SESS_NOTHROTTLE)
2887 {
2888 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2889 throttle_session(s, 0, 0);
2890 s_actions++;
2891 send++;
2892 }
2893 else if (a & CLI_SESS_THROTTLE)
2894 {
2895 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2896 cli_session_actions[s].throttle_in,
2897 cli_session_actions[s].throttle_out);
2898
2899 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2900 s_actions++;
2901 send++;
2902 }
2903
2904 if (a & CLI_SESS_NOFILTER)
2905 {
2906 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2907 filter_session(s, 0, 0);
2908 s_actions++;
2909 send++;
2910 }
2911 else if (a & CLI_SESS_FILTER)
2912 {
2913 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2914 cli_session_actions[s].filter_in,
2915 cli_session_actions[s].filter_out);
2916
2917 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2918 s_actions++;
2919 send++;
2920 }
2921
2922 if (send)
2923 cluster_send_session(s);
2924 }
2925
2926 // RADIUS interim accounting
2927 if (config->radius_accounting && config->radius_interim > 0
2928 && session[s].ip && !session[s].walled_garden
2929 && !sess_local[s].radius // RADIUS already in progress
2930 && time_now - sess_local[s].last_interim >= config->radius_interim)
2931 {
2932 int rad = radiusnew(s);
2933 if (!rad)
2934 {
2935 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2936 STAT(radius_overflow);
2937 continue;
2938 }
2939
2940 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2941 session[s].user, session[s].unique_id);
2942
2943 radiussend(rad, RADIUSINTERIM);
2944 sess_local[s].last_interim = time_now;
2945 s_actions++;
2946 }
2947 }
2948
2949 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2950 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2951 }
2952
2953 //
2954 // Are we in the middle of a tunnel update, or radius
2955 // requests??
2956 //
2957 static int still_busy(void)
2958 {
2959 int i;
2960 static clockt last_talked = 0;
2961 static clockt start_busy_wait = 0;
2962
2963 if (!config->cluster_iam_master)
2964 {
2965 #ifdef BGP
2966 static time_t stopped_bgp = 0;
2967 if (bgp_configured)
2968 {
2969 if (!stopped_bgp)
2970 {
2971 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2972
2973 for (i = 0; i < BGP_NUM_PEERS; i++)
2974 if (bgp_peers[i].state == Established)
2975 bgp_stop(&bgp_peers[i]);
2976
2977 stopped_bgp = time_now;
2978
2979 // we don't want to become master
2980 cluster_send_ping(0);
2981
2982 return 1;
2983 }
2984
2985 if (time_now < (stopped_bgp + QUIT_DELAY))
2986 return 1;
2987 }
2988 #endif /* BGP */
2989
2990 return 0;
2991 }
2992
2993 if (main_quit == QUIT_SHUTDOWN)
2994 {
2995 static int dropped = 0;
2996 if (!dropped)
2997 {
2998 int i;
2999
3000 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3001 for (i = 1; i < MAXTUNNEL; i++)
3002 if (tunnel[i].ip || tunnel[i].state)
3003 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3004
3005 dropped = 1;
3006 }
3007 }
3008
3009 if (start_busy_wait == 0)
3010 start_busy_wait = TIME;
3011
3012 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3013 {
3014 if (!tunnel[i].controlc)
3015 continue;
3016
3017 if (last_talked != TIME)
3018 {
3019 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3020 last_talked = TIME;
3021 }
3022 return 1;
3023 }
3024
3025 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3026 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3027 {
3028 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3029 return 0;
3030 }
3031
3032 for (i = 1; i < MAXRADIUS; i++)
3033 {
3034 if (radius[i].state == RADIUSNULL)
3035 continue;
3036 if (radius[i].state == RADIUSWAIT)
3037 continue;
3038
3039 if (last_talked != TIME)
3040 {
3041 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3042 last_talked = TIME;
3043 }
3044 return 1;
3045 }
3046
3047 return 0;
3048 }
3049
3050 #ifdef HAVE_EPOLL
3051 # include <sys/epoll.h>
3052 #else
3053 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3054 # include "fake_epoll.h"
3055 #endif
3056
3057 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3058 #define BASE_FDS 6
3059
3060 // additional polled fds
3061 #ifdef BGP
3062 # define EXTRA_FDS BGP_NUM_PEERS
3063 #else
3064 # define EXTRA_FDS 0
3065 #endif
3066
3067 // main loop - gets packets on tun or udp and processes them
3068 static void mainloop(void)
3069 {
3070 int i;
3071 uint8_t buf[65536];
3072 clockt next_cluster_ping = 0; // send initial ping immediately
3073 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3074 int maxevent = sizeof(events)/sizeof(*events);
3075
3076 if ((epollfd = epoll_create(maxevent)) < 0)
3077 {
3078 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3079 exit(1);
3080 }
3081
3082 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3083 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3084
3085 /* setup our fds to poll for input */
3086 {
3087 static struct event_data d[BASE_FDS];
3088 struct epoll_event e;
3089
3090 e.events = EPOLLIN;
3091 i = 0;
3092
3093 d[i].type = FD_TYPE_CLI;
3094 e.data.ptr = &d[i++];
3095 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3096
3097 d[i].type = FD_TYPE_CLUSTER;
3098 e.data.ptr = &d[i++];
3099 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3100
3101 d[i].type = FD_TYPE_TUN;
3102 e.data.ptr = &d[i++];
3103 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3104
3105 d[i].type = FD_TYPE_UDP;
3106 e.data.ptr = &d[i++];
3107 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3108
3109 d[i].type = FD_TYPE_CONTROL;
3110 e.data.ptr = &d[i++];
3111 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3112
3113 d[i].type = FD_TYPE_DAE;
3114 e.data.ptr = &d[i++];
3115 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3116 }
3117
3118 #ifdef BGP
3119 signal(SIGPIPE, SIG_IGN);
3120 bgp_setup(config->as_number);
3121 if (config->bind_address)
3122 bgp_add_route(config->bind_address, 0xffffffff);
3123
3124 for (i = 0; i < BGP_NUM_PEERS; i++)
3125 {
3126 if (config->neighbour[i].name[0])
3127 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3128 config->neighbour[i].as, config->neighbour[i].keepalive,
3129 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3130 }
3131 #endif /* BGP */
3132
3133 while (!main_quit || still_busy())
3134 {
3135 int more = 0;
3136 int n;
3137
3138 if (config->reload_config)
3139 {
3140 // Update the config state based on config settings
3141 update_config();
3142 }
3143
3144 #ifdef BGP
3145 bgp_set_poll();
3146 #endif /* BGP */
3147
3148 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3149 STAT(select_called);
3150
3151 TIME = now(NULL);
3152 if (n < 0)
3153 {
3154 if (errno == EINTR ||
3155 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3156 continue;
3157
3158 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3159 break; // exit
3160 }
3161
3162 if (n)
3163 {
3164 struct sockaddr_in addr;
3165 socklen_t alen;
3166 int c, s;
3167 int udp_ready = 0;
3168 int tun_ready = 0;
3169 int cluster_ready = 0;
3170 int udp_pkts = 0;
3171 int tun_pkts = 0;
3172 int cluster_pkts = 0;
3173 #ifdef BGP
3174 uint32_t bgp_events[BGP_NUM_PEERS];
3175 memset(bgp_events, 0, sizeof(bgp_events));
3176 #endif /* BGP */
3177
3178 for (c = n, i = 0; i < c; i++)
3179 {
3180 struct event_data *d = events[i].data.ptr;
3181 switch (d->type)
3182 {
3183 case FD_TYPE_CLI: // CLI connections
3184 {
3185 int cli;
3186
3187 alen = sizeof(addr);
3188 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3189 {
3190 cli_do(cli);
3191 close(cli);
3192 }
3193 else
3194 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3195
3196 n--;
3197 break;
3198 }
3199
3200 // these are handled below, with multiple interleaved reads
3201 case FD_TYPE_CLUSTER: cluster_ready++; break;
3202 case FD_TYPE_TUN: tun_ready++; break;
3203 case FD_TYPE_UDP: udp_ready++; break;
3204
3205 case FD_TYPE_CONTROL: // nsctl commands
3206 alen = sizeof(addr);
3207 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3208 n--;
3209 break;
3210
3211 case FD_TYPE_DAE: // DAE requests
3212 alen = sizeof(addr);
3213 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3214 n--;
3215 break;
3216
3217 case FD_TYPE_RADIUS: // RADIUS response
3218 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3219 if (s >= 0 && config->cluster_iam_master)
3220 processrad(buf, s, d->index);
3221
3222 n--;
3223 break;
3224
3225 #ifdef BGP
3226 case FD_TYPE_BGP:
3227 bgp_events[d->index] = events[i].events;
3228 n--;
3229 break;
3230 #endif /* BGP */
3231
3232 default:
3233 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3234 }
3235 }
3236
3237 #ifdef BGP
3238 bgp_process(bgp_events);
3239 #endif /* BGP */
3240
3241 for (c = 0; n && c < config->multi_read_count; c++)
3242 {
3243 // L2TP
3244 if (udp_ready)
3245 {
3246 alen = sizeof(addr);
3247 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3248 {
3249 processudp(buf, s, &addr);
3250 udp_pkts++;
3251 }
3252 else
3253 {
3254 udp_ready = 0;
3255 n--;
3256 }
3257 }
3258
3259 // incoming IP
3260 if (tun_ready)
3261 {
3262 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3263 {
3264 processtun(buf, s);
3265 tun_pkts++;
3266 }
3267 else
3268 {
3269 tun_ready = 0;
3270 n--;
3271 }
3272 }
3273
3274 // cluster
3275 if (cluster_ready)
3276 {
3277 alen = sizeof(addr);
3278 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3279 {
3280 processcluster(buf, s, addr.sin_addr.s_addr);
3281 cluster_pkts++;
3282 }
3283 else
3284 {
3285 cluster_ready = 0;
3286 n--;
3287 }
3288 }
3289 }
3290
3291 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3292 STAT(multi_read_used);
3293
3294 if (c >= config->multi_read_count)
3295 {
3296 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3297 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3298
3299 STAT(multi_read_exceeded);
3300 more++;
3301 }
3302 }
3303
3304 // Runs on every machine (master and slaves).
3305 if (next_cluster_ping <= TIME)
3306 {
3307 // Check to see which of the cluster is still alive..
3308
3309 cluster_send_ping(basetime); // Only does anything if we're a slave
3310 cluster_check_master(); // ditto.
3311
3312 cluster_heartbeat(); // Only does anything if we're a master.
3313 cluster_check_slaves(); // ditto.
3314
3315 master_update_counts(); // If we're a slave, send our byte counters to our master.
3316
3317 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3318 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3319 else
3320 next_cluster_ping = TIME + config->cluster_hb_interval;
3321 }
3322
3323 if (!config->cluster_iam_master)
3324 continue;
3325
3326 // Run token bucket filtering queue..
3327 // Only run it every 1/10th of a second.
3328 {
3329 static clockt last_run = 0;
3330 if (last_run != TIME)
3331 {
3332 last_run = TIME;
3333 tbf_run_timer();
3334 }
3335 }
3336
3337 // Handle timeouts, retries etc.
3338 {
3339 static double last_clean = 0;
3340 double this_clean;
3341 double diff;
3342
3343 TIME = now(&this_clean);
3344 diff = this_clean - last_clean;
3345
3346 // Run during idle time (after we've handled
3347 // all incoming packets) or every 1/10th sec
3348 if (!more || diff > 0.1)
3349 {
3350 regular_cleanups(diff);
3351 last_clean = this_clean;
3352 }
3353 }
3354
3355 if (*config->accounting_dir)
3356 {
3357 static clockt next_acct = 0;
3358 static clockt next_shut_acct = 0;
3359
3360 if (next_acct <= TIME)
3361 {
3362 // Dump accounting data
3363 next_acct = TIME + ACCT_TIME;
3364 next_shut_acct = TIME + ACCT_SHUT_TIME;
3365 dump_acct_info(1);
3366 }
3367 else if (next_shut_acct <= TIME)
3368 {
3369 // Dump accounting data for shutdown sessions
3370 next_shut_acct = TIME + ACCT_SHUT_TIME;
3371 if (shut_acct_n)
3372 dump_acct_info(0);
3373 }
3374 }
3375 }
3376
3377 // Are we the master and shutting down??
3378 if (config->cluster_iam_master)
3379 cluster_heartbeat(); // Flush any queued changes..
3380
3381 // Ok. Notify everyone we're shutting down. If we're
3382 // the master, this will force an election.
3383 cluster_send_ping(0);
3384
3385 //
3386 // Important!!! We MUST not process any packets past this point!
3387 LOG(1, 0, 0, "Shutdown complete\n");
3388 }
3389
3390 static void stripdomain(char *host)
3391 {
3392 char *p;
3393
3394 if ((p = strchr(host, '.')))
3395 {
3396 char *domain = 0;
3397 char _domain[1024];
3398
3399 // strip off domain
3400 FILE *resolv = fopen("/etc/resolv.conf", "r");
3401 if (resolv)
3402 {
3403 char buf[1024];
3404 char *b;
3405
3406 while (fgets(buf, sizeof(buf), resolv))
3407 {
3408 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3409 continue;
3410
3411 if (!isspace(buf[6]))
3412 continue;
3413
3414 b = buf + 7;
3415 while (isspace(*b)) b++;
3416
3417 if (*b)
3418 {
3419 char *d = b;
3420 while (*b && !isspace(*b)) b++;
3421 *b = 0;
3422 if (buf[0] == 'd') // domain is canonical
3423 {
3424 domain = d;
3425 break;
3426 }
3427
3428 // first search line
3429 if (!domain)
3430 {
3431 // hold, may be subsequent domain line
3432 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3433 domain = _domain;
3434 }
3435 }
3436 }
3437
3438 fclose(resolv);
3439 }
3440
3441 if (domain)
3442 {
3443 int hl = strlen(host);
3444 int dl = strlen(domain);
3445 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3446 host[hl -dl - 1] = 0;
3447 }
3448 else
3449 {
3450 *p = 0; // everything after first dot
3451 }
3452 }
3453 }
3454
3455 // Init data structures
3456 static void initdata(int optdebug, char *optconfig)
3457 {
3458 int i;
3459
3460 if (!(config = shared_malloc(sizeof(configt))))
3461 {
3462 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3463 exit(1);
3464 }
3465
3466 memset(config, 0, sizeof(configt));
3467 time(&config->start_time);
3468 strncpy(config->config_file, optconfig, strlen(optconfig));
3469 config->debug = optdebug;
3470 config->num_tbfs = MAXTBFS;
3471 config->rl_rate = 28; // 28kbps
3472 config->cluster_master_min_adv = 1;
3473 config->ppp_restart_time = 3;
3474 config->ppp_max_configure = 10;
3475 config->ppp_max_failure = 5;
3476 strcpy(config->random_device, RANDOMDEVICE);
3477
3478 log_stream = stderr;
3479
3480 #ifdef RINGBUFFER
3481 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3482 {
3483 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3484 exit(1);
3485 }
3486 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3487 #endif
3488
3489 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3490 {
3491 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3492 exit(1);
3493 }
3494 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3495 {
3496 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3497 exit(1);
3498 }
3499 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3500 {
3501 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3502 exit(1);
3503 }
3504
3505 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3506 {
3507 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3508 exit(1);
3509 }
3510
3511 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3512 {
3513 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3514 exit(1);
3515 }
3516
3517 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3518 {
3519 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3520 exit(1);
3521 }
3522
3523 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3524 {
3525 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3526 exit(1);
3527 }
3528 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3529
3530 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3531 {
3532 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3533 exit(1);
3534 }
3535 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3536
3537 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3538 {
3539 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3540 exit(1);
3541 }
3542 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3543
3544 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3545 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3546 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3547 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3548
3549 // Put all the sessions on the free list marked as undefined.
3550 for (i = 1; i < MAXSESSION; i++)
3551 {
3552 session[i].next = i + 1;
3553 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3554 }
3555 session[MAXSESSION - 1].next = 0;
3556 sessionfree = 1;
3557
3558 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3559 for (i = 1; i < MAXTUNNEL; i++)
3560 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3561
3562 if (!*hostname)
3563 {
3564 // Grab my hostname unless it's been specified
3565 gethostname(hostname, sizeof(hostname));
3566 stripdomain(hostname);
3567 }
3568
3569 _statistics->start_time = _statistics->last_reset = time(NULL);
3570
3571 #ifdef BGP
3572 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3573 {
3574 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3575 exit(1);
3576 }
3577 #endif /* BGP */
3578 }
3579
3580 static int assign_ip_address(sessionidt s)
3581 {
3582 uint32_t i;
3583 int best = -1;
3584 time_t best_time = time_now;
3585 char *u = session[s].user;
3586 char reuse = 0;
3587
3588
3589 CSTAT(assign_ip_address);
3590
3591 for (i = 1; i < ip_pool_size; i++)
3592 {
3593 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3594 continue;
3595
3596 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3597 {
3598 best = i;
3599 reuse = 1;
3600 break;
3601 }
3602
3603 if (ip_address_pool[i].last < best_time)
3604 {
3605 best = i;
3606 if (!(best_time = ip_address_pool[i].last))
3607 break; // never used, grab this one
3608 }
3609 }
3610
3611 if (best < 0)
3612 {
3613 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3614 return 0;
3615 }
3616
3617 session[s].ip = ip_address_pool[best].address;
3618 session[s].ip_pool_index = best;
3619 ip_address_pool[best].assigned = 1;
3620 ip_address_pool[best].last = time_now;
3621 ip_address_pool[best].session = s;
3622 if (session[s].walled_garden)
3623 /* Don't track addresses of users in walled garden (note: this
3624 means that their address isn't "sticky" even if they get
3625 un-gardened). */
3626 ip_address_pool[best].user[0] = 0;
3627 else
3628 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3629
3630 STAT(ip_allocated);
3631 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3632 reuse ? "Reusing" : "Allocating", best);
3633
3634 return 1;
3635 }
3636
3637 static void free_ip_address(sessionidt s)
3638 {
3639 int i = session[s].ip_pool_index;
3640
3641
3642 CSTAT(free_ip_address);
3643
3644 if (!session[s].ip)
3645 return; // what the?
3646
3647 if (i < 0) // Is this actually part of the ip pool?
3648 i = 0;
3649
3650 STAT(ip_freed);
3651 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3652 session[s].ip = 0;
3653 ip_address_pool[i].assigned = 0;
3654 ip_address_pool[i].session = 0;
3655 ip_address_pool[i].last = time_now;
3656 }
3657
3658 //
3659 // Fsck the address pool against the session table.
3660 // Normally only called when we become a master.
3661 //
3662 // This isn't perfect: We aren't keep tracking of which
3663 // users used to have an IP address.
3664 //
3665 void rebuild_address_pool(void)
3666 {
3667 int i;
3668
3669 //
3670 // Zero the IP pool allocation, and build
3671 // a map from IP address to pool index.
3672 for (i = 1; i < MAXIPPOOL; ++i)
3673 {
3674 ip_address_pool[i].assigned = 0;
3675 ip_address_pool[i].session = 0;
3676 if (!ip_address_pool[i].address)
3677 continue;
3678
3679 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3680 }
3681
3682 for (i = 0; i < MAXSESSION; ++i)
3683 {
3684 int ipid;
3685 if (!(session[i].opened && session[i].ip))
3686 continue;
3687
3688 ipid = - lookup_ipmap(htonl(session[i].ip));
3689
3690 if (session[i].ip_pool_index < 0)
3691 {
3692 // Not allocated out of the pool.
3693 if (ipid < 1) // Not found in the pool either? good.
3694 continue;
3695
3696 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3697 i, fmtaddr(session[i].ip, 0), ipid);
3698
3699 // Fall through and process it as part of the pool.
3700 }
3701
3702
3703 if (ipid > MAXIPPOOL || ipid < 0)
3704 {
3705 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3706 ipid = -1;
3707 session[i].ip_pool_index = ipid;
3708 continue;
3709 }
3710
3711 ip_address_pool[ipid].assigned = 1;
3712 ip_address_pool[ipid].session = i;
3713 ip_address_pool[ipid].last = time_now;
3714 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3715 session[i].ip_pool_index = ipid;
3716 cache_ipmap(session[i].ip, i); // Fix the ip map.
3717 }
3718 }
3719
3720 //
3721 // Fix the address pool to match a changed session.
3722 // (usually when the master sends us an update).
3723 static void fix_address_pool(int sid)
3724 {
3725 int ipid;
3726
3727 ipid = session[sid].ip_pool_index;
3728
3729 if (ipid > ip_pool_size)
3730 return; // Ignore it. rebuild_address_pool will fix it up.
3731
3732 if (ip_address_pool[ipid].address != session[sid].ip)
3733 return; // Just ignore it. rebuild_address_pool will take care of it.
3734
3735 ip_address_pool[ipid].assigned = 1;
3736 ip_address_pool[ipid].session = sid;
3737 ip_address_pool[ipid].last = time_now;
3738 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3739 }
3740
3741 //
3742 // Add a block of addresses to the IP pool to hand out.
3743 //
3744 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3745 {
3746 int i;
3747 if (mask == 0)
3748 mask = 0xffffffff; // Host route only.
3749
3750 addr &= mask;
3751
3752 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3753 return ;
3754
3755 for (i = addr ;(i & mask) == addr; ++i)
3756 {
3757 if ((i & 0xff) == 0 || (i&0xff) == 255)
3758 continue; // Skip 0 and broadcast addresses.
3759
3760 ip_address_pool[ip_pool_size].address = i;
3761 ip_address_pool[ip_pool_size].assigned = 0;
3762 ++ip_pool_size;
3763 if (ip_pool_size >= MAXIPPOOL)
3764 {
3765 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3766 return;
3767 }
3768 }
3769 }
3770
3771 // Initialize the IP address pool
3772 static void initippool()
3773 {
3774 FILE *f;
3775 char *p;
3776 char buf[4096];
3777 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3778
3779 if (!(f = fopen(IPPOOLFILE, "r")))
3780 {
3781 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3782 exit(1);
3783 }
3784
3785 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3786 {
3787 char *pool = buf;
3788 buf[4095] = 0; // Force it to be zero terminated/
3789
3790 if (*buf == '#' || *buf == '\n')
3791 continue; // Skip comments / blank lines
3792 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3793 if ((p = (char *)strchr(buf, ':')))
3794 {
3795 in_addr_t src;
3796 *p = '\0';
3797 src = inet_addr(buf);
3798 if (src == INADDR_NONE)
3799 {
3800 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3801 exit(1);
3802 }
3803 // This entry is for a specific IP only
3804 if (src != config->bind_address)
3805 continue;
3806 *p = ':';
3807 pool = p+1;
3808 }
3809 if ((p = (char *)strchr(pool, '/')))
3810 {
3811 // It's a range
3812 int numbits = 0;
3813 in_addr_t start = 0, mask = 0;
3814
3815 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3816 *p++ = 0;
3817 if (!*p || !(numbits = atoi(p)))
3818 {
3819 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3820 continue;
3821 }
3822 start = ntohl(inet_addr(pool));
3823 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3824
3825 // Add a static route for this pool
3826 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3827 fmtaddr(htonl(start), 0), 32 + mask);
3828
3829 routeset(0, start, mask, 0, 1);
3830
3831 add_to_ip_pool(start, mask);
3832 }
3833 else
3834 {
3835 // It's a single ip address
3836 add_to_ip_pool(inet_addr(pool), 0);
3837 }
3838 }
3839 fclose(f);
3840 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3841 }
3842
3843 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3844 {
3845 struct sockaddr_in snoop_addr = {0};
3846 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3847 return;
3848
3849 snoop_addr.sin_family = AF_INET;
3850 snoop_addr.sin_addr.s_addr = destination;
3851 snoop_addr.sin_port = ntohs(port);
3852
3853 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3854 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3855 htons(snoop_addr.sin_port));
3856
3857 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3858 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3859
3860 STAT(packets_snooped);
3861 }
3862
3863 static int dump_session(FILE **f, sessiont *s)
3864 {
3865 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3866 return 1;
3867
3868 if (!*f)
3869 {
3870 char filename[1024];
3871 char timestr[64];
3872 time_t now = time(NULL);
3873
3874 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3875 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3876
3877 if (!(*f = fopen(filename, "w")))
3878 {
3879 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3880 return 0;
3881 }
3882
3883 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3884 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3885 "# host: %s\n"
3886 "# endpoint: %s\n"
3887 "# time: %ld\n"
3888 "# uptime: %ld\n"
3889 "# format: username ip qos uptxoctets downrxoctets\n",
3890 hostname,
3891 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3892 now,
3893 now - basetime);
3894 }
3895
3896 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3897 fprintf(*f, "%s %s %d %u %u\n",
3898 s->user, // username
3899 fmtaddr(htonl(s->ip), 0), // ip
3900 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3901 (uint32_t) s->cin_delta, // uptxoctets
3902 (uint32_t) s->cout_delta); // downrxoctets
3903
3904 s->cin_delta = s->cout_delta = 0;
3905
3906 return 1;
3907 }
3908
3909 static void dump_acct_info(int all)
3910 {
3911 int i;
3912 FILE *f = NULL;
3913
3914
3915 CSTAT(dump_acct_info);
3916
3917 if (shut_acct_n)
3918 {
3919 for (i = 0; i < shut_acct_n; i++)
3920 dump_session(&f, &shut_acct[i]);
3921
3922 shut_acct_n = 0;
3923 }
3924
3925 if (all)
3926 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3927 dump_session(&f, &session[i]);
3928
3929 if (f)
3930 fclose(f);
3931 }
3932
3933 // Main program
3934 int main(int argc, char *argv[])
3935 {
3936 int i;
3937 int optdebug = 0;
3938 char *optconfig = CONFIGFILE;
3939
3940 time(&basetime); // start clock
3941
3942 // scan args
3943 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3944 {
3945 switch (i)
3946 {
3947 case 'd':
3948 if (fork()) exit(0);
3949 setsid();
3950 freopen("/dev/null", "r", stdin);
3951 freopen("/dev/null", "w", stdout);
3952 freopen("/dev/null", "w", stderr);
3953 break;
3954 case 'v':
3955 optdebug++;
3956 break;
3957 case 'c':
3958 optconfig = optarg;
3959 break;
3960 case 'h':
3961 snprintf(hostname, sizeof(hostname), "%s", optarg);
3962 break;
3963 default:
3964 printf("Args are:\n"
3965 "\t-d\t\tDetach from terminal\n"
3966 "\t-c <file>\tConfig file\n"
3967 "\t-h <hostname>\tForce hostname\n"
3968 "\t-v\t\tDebug\n");
3969
3970 return (0);
3971 break;
3972 }
3973 }
3974
3975 // Start the timer routine off
3976 time(&time_now);
3977 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3978 signal(SIGALRM, sigalrm_handler);
3979 siginterrupt(SIGALRM, 0);
3980
3981 initplugins();
3982 initdata(optdebug, optconfig);
3983
3984 init_cli(hostname);
3985 read_config_file();
3986 init_tbf(config->num_tbfs);
3987
3988 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3989 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3990 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3991 {
3992 struct rlimit rlim;
3993 rlim.rlim_cur = RLIM_INFINITY;
3994 rlim.rlim_max = RLIM_INFINITY;
3995 // Remove the maximum core size
3996 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3997 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3998
3999 // Make core dumps go to /tmp
4000 chdir("/tmp");
4001 }
4002
4003 if (config->scheduler_fifo)
4004 {
4005 int ret;
4006 struct sched_param params = {0};
4007 params.sched_priority = 1;
4008
4009 if (get_nprocs() < 2)
4010 {
4011 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4012 config->scheduler_fifo = 0;
4013 }
4014 else
4015 {
4016 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4017 {
4018 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4019 }
4020 else
4021 {
4022 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4023 config->scheduler_fifo = 0;
4024 }
4025 }
4026 }
4027
4028 /* Set up the cluster communications port. */
4029 if (cluster_init() < 0)
4030 exit(1);
4031
4032 inittun();
4033 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4034
4035 initudp();
4036 initrad();
4037 initippool();
4038
4039 // seed prng
4040 {
4041 unsigned seed = time_now ^ getpid();
4042 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4043 srand(seed);
4044 }
4045
4046 signal(SIGHUP, sighup_handler);
4047 signal(SIGCHLD, sigchild_handler);
4048 signal(SIGTERM, shutdown_handler);
4049 signal(SIGINT, shutdown_handler);
4050 signal(SIGQUIT, shutdown_handler);
4051
4052 // Prevent us from getting paged out
4053 if (config->lock_pages)
4054 {
4055 if (!mlockall(MCL_CURRENT))
4056 LOG(1, 0, 0, "Locking pages into memory\n");
4057 else
4058 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4059 }
4060
4061 alarm(1);
4062
4063 // Drop privileges here
4064 if (config->target_uid > 0 && geteuid() == 0)
4065 setuid(config->target_uid);
4066
4067 mainloop();
4068
4069 /* remove plugins (so cleanup code gets run) */
4070 plugins_done();
4071
4072 // Remove the PID file if we wrote it
4073 if (config->wrote_pid && *config->pid_file == '/')
4074 unlink(config->pid_file);
4075
4076 /* kill CLI children */
4077 signal(SIGTERM, SIG_IGN);
4078 kill(0, SIGTERM);
4079 return 0;
4080 }
4081
4082 static void sighup_handler(int sig)
4083 {
4084 if (log_stream)
4085 {
4086 if (log_stream != stderr)
4087 fclose(log_stream);
4088
4089 log_stream = NULL;
4090 }
4091
4092 read_config_file();
4093 }
4094
4095 static void sigalrm_handler(int sig)
4096 {
4097 // Log current traffic stats
4098
4099 snprintf(config->bandwidth, sizeof(config->bandwidth),
4100 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4101 (udp_rx / 1024.0 / 1024.0 * 8),
4102 (eth_tx / 1024.0 / 1024.0 * 8),
4103 (eth_rx / 1024.0 / 1024.0 * 8),
4104 (udp_tx / 1024.0 / 1024.0 * 8),
4105 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4106 udp_rx_pkt, eth_rx_pkt);
4107
4108 udp_tx = udp_rx = 0;
4109 udp_rx_pkt = eth_rx_pkt = 0;
4110 eth_tx = eth_rx = 0;
4111
4112 if (config->dump_speed)
4113 printf("%s\n", config->bandwidth);
4114
4115 // Update the internal time counter
4116 time(&time_now);
4117 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4118 alarm(1);
4119
4120 {
4121 // Run timer hooks
4122 struct param_timer p = { time_now };
4123 run_plugins(PLUGIN_TIMER, &p);
4124 }
4125
4126 }
4127
4128 static void shutdown_handler(int sig)
4129 {
4130 LOG(1, 0, 0, "Shutting down\n");
4131 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4132 }
4133
4134 static void sigchild_handler(int sig)
4135 {
4136 while (waitpid(-1, NULL, WNOHANG) > 0)
4137 ;
4138 }
4139
4140 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4141 {
4142 MD5_CTX ctx;
4143 *challenge_response = NULL;
4144
4145 if (!*config->l2tpsecret)
4146 {
4147 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4148 return;
4149 }
4150
4151 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4152
4153 *challenge_response = calloc(17, 1);
4154
4155 MD5_Init(&ctx);
4156 MD5_Update(&ctx, &id, 1);
4157 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4158 MD5_Update(&ctx, challenge, challenge_length);
4159 MD5_Final(*challenge_response, &ctx);
4160
4161 return;
4162 }
4163
4164 static int facility_value(char *name)
4165 {
4166 int i;
4167 for (i = 0; facilitynames[i].c_name; i++)
4168 {
4169 if (strcmp(facilitynames[i].c_name, name) == 0)
4170 return facilitynames[i].c_val;
4171 }
4172 return 0;
4173 }
4174
4175 static void update_config()
4176 {
4177 int i;
4178 char *p;
4179 static int timeout = 0;
4180 static int interval = 0;
4181
4182 // Update logging
4183 closelog();
4184 syslog_log = 0;
4185 if (log_stream)
4186 {
4187 if (log_stream != stderr)
4188 fclose(log_stream);
4189
4190 log_stream = NULL;
4191 }
4192
4193 if (*config->log_filename)
4194 {
4195 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4196 {
4197 char *p = config->log_filename + 7;
4198 if (*p)
4199 {
4200 openlog("l2tpns", LOG_PID, facility_value(p));
4201 syslog_log = 1;
4202 }
4203 }
4204 else if (strchr(config->log_filename, '/') == config->log_filename)
4205 {
4206 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4207 {
4208 fseek(log_stream, 0, SEEK_END);
4209 setbuf(log_stream, NULL);
4210 }
4211 else
4212 {
4213 log_stream = stderr;
4214 setbuf(log_stream, NULL);
4215 }
4216 }
4217 }
4218 else
4219 {
4220 log_stream = stderr;
4221 setbuf(log_stream, NULL);
4222 }
4223
4224 // Update radius
4225 config->numradiusservers = 0;
4226 for (i = 0; i < MAXRADSERVER; i++)
4227 if (config->radiusserver[i])
4228 {
4229 config->numradiusservers++;
4230 // Set radius port: if not set, take the port from the
4231 // first radius server. For the first radius server,
4232 // take the #defined default value from l2tpns.h
4233
4234 // test twice, In case someone works with
4235 // a secondary radius server without defining
4236 // a primary one, this will work even then.
4237 if (i > 0 && !config->radiusport[i])
4238 config->radiusport[i] = config->radiusport[i-1];
4239 if (!config->radiusport[i])
4240 config->radiusport[i] = RADPORT;
4241 }
4242
4243 if (!config->numradiusservers)
4244 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4245
4246 // parse radius_authtypes_s
4247 config->radius_authtypes = config->radius_authprefer = 0;
4248 p = config->radius_authtypes_s;
4249 while (p && *p)
4250 {
4251 char *s = strpbrk(p, " \t,");
4252 int type = 0;
4253
4254 if (s)
4255 {
4256 *s++ = 0;
4257 while (*s == ' ' || *s == '\t')
4258 s++;
4259
4260 if (!*s)
4261 s = 0;
4262 }
4263
4264 if (!strncasecmp("chap", p, strlen(p)))
4265 type = AUTHCHAP;
4266 else if (!strncasecmp("pap", p, strlen(p)))
4267 type = AUTHPAP;
4268 else
4269 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4270
4271 config->radius_authtypes |= type;
4272 if (!config->radius_authprefer)
4273 config->radius_authprefer = type;
4274
4275 p = s;
4276 }
4277
4278 if (!config->radius_authtypes)
4279 {
4280 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4281 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4282 }
4283
4284 // normalise radius_authtypes_s
4285 if (config->radius_authprefer == AUTHPAP)
4286 {
4287 strcpy(config->radius_authtypes_s, "pap");
4288 if (config->radius_authtypes & AUTHCHAP)
4289 strcat(config->radius_authtypes_s, ", chap");
4290 }
4291 else
4292 {
4293 strcpy(config->radius_authtypes_s, "chap");
4294 if (config->radius_authtypes & AUTHPAP)
4295 strcat(config->radius_authtypes_s, ", pap");
4296 }
4297
4298 if (!config->radius_dae_port)
4299 config->radius_dae_port = DAEPORT;
4300
4301 // re-initialise the random number source
4302 initrandom(config->random_device);
4303
4304 // Update plugins
4305 for (i = 0; i < MAXPLUGINS; i++)
4306 {
4307 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4308 continue;
4309
4310 if (*config->plugins[i])
4311 {
4312 // Plugin added
4313 add_plugin(config->plugins[i]);
4314 }
4315 else if (*config->old_plugins[i])
4316 {
4317 // Plugin removed
4318 remove_plugin(config->old_plugins[i]);
4319 }
4320 }
4321
4322 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4323 if (!config->multi_read_count) config->multi_read_count = 10;
4324 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4325 if (!*config->cluster_interface)
4326 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4327
4328 if (!config->cluster_hb_interval)
4329 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4330
4331 if (!config->cluster_hb_timeout)
4332 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4333
4334 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4335 {
4336 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4337 // late, ensure we're sufficiently larger than that
4338 int t = 4 * config->cluster_hb_interval + 11;
4339
4340 if (config->cluster_hb_timeout < t)
4341 {
4342 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4343 config->cluster_hb_timeout = t;
4344 }
4345
4346 // Push timing changes to the slaves immediately if we're the master
4347 if (config->cluster_iam_master)
4348 cluster_heartbeat();
4349
4350 interval = config->cluster_hb_interval;
4351 timeout = config->cluster_hb_timeout;
4352 }
4353
4354 // Write PID file
4355 if (*config->pid_file == '/' && !config->wrote_pid)
4356 {
4357 FILE *f;
4358 if ((f = fopen(config->pid_file, "w")))
4359 {
4360 fprintf(f, "%d\n", getpid());
4361 fclose(f);
4362 config->wrote_pid = 1;
4363 }
4364 else
4365 {
4366 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4367 }
4368 }
4369
4370 config->reload_config = 0;
4371 }
4372
4373 static void read_config_file()
4374 {
4375 FILE *f;
4376
4377 if (!config->config_file) return;
4378 if (!(f = fopen(config->config_file, "r")))
4379 {
4380 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4381 return;
4382 }
4383
4384 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4385 cli_do_file(f);
4386 LOG(3, 0, 0, "Done reading config file\n");
4387 fclose(f);
4388 update_config();
4389 }
4390
4391 int sessionsetup(sessionidt s, tunnelidt t)
4392 {
4393 // A session now exists, set it up
4394 in_addr_t ip;
4395 char *user;
4396 sessionidt i;
4397 int r;
4398
4399 CSTAT(sessionsetup);
4400
4401 LOG(3, s, t, "Doing session setup for session\n");
4402
4403 if (!session[s].ip)
4404 {
4405 assign_ip_address(s);
4406 if (!session[s].ip)
4407 {
4408 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4409 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4410 return 0;
4411 }
4412 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4413 fmtaddr(htonl(session[s].ip), 0));
4414 }
4415
4416
4417 // Make sure this is right
4418 session[s].tunnel = t;
4419
4420 // zap old sessions with same IP and/or username
4421 // Don't kill gardened sessions - doing so leads to a DoS
4422 // from someone who doesn't need to know the password
4423 {
4424 ip = session[s].ip;
4425 user = session[s].user;
4426 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4427 {
4428 if (i == s) continue;
4429 if (!session[s].opened) continue;
4430 if (ip == session[i].ip)
4431 {
4432 sessionkill(i, "Duplicate IP address");
4433 continue;
4434 }
4435
4436 if (config->allow_duplicate_users) continue;
4437 if (session[s].walled_garden || session[i].walled_garden) continue;
4438 if (!strcasecmp(user, session[i].user))
4439 sessionkill(i, "Duplicate session for users");
4440 }
4441 }
4442
4443 {
4444 int routed = 0;
4445
4446 // Add the route for this session.
4447 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4448 {
4449 if ((session[s].ip & session[s].route[r].mask) ==
4450 (session[s].route[r].ip & session[s].route[r].mask))
4451 routed++;
4452
4453 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4454 }
4455
4456 // Static IPs need to be routed if not already
4457 // convered by a Framed-Route. Anything else is part
4458 // of the IP address pool and is already routed, it
4459 // just needs to be added to the IP cache.
4460 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4461 if (session[s].ip_pool_index == -1) // static ip
4462 {
4463 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4464 }
4465 else
4466 cache_ipmap(session[s].ip, s);
4467 }
4468
4469 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4470 lcp_open(s, t); // transition to Network phase and send initial IPCP
4471
4472 // Run the plugin's against this new session.
4473 {
4474 struct param_new_session data = { &tunnel[t], &session[s] };
4475 run_plugins(PLUGIN_NEW_SESSION, &data);
4476 }
4477
4478 // Allocate TBFs if throttled
4479 if (session[s].throttle_in || session[s].throttle_out)
4480 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4481
4482 session[s].last_packet = time_now;
4483
4484 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4485 fmtaddr(htonl(session[s].ip), 0),
4486 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4487
4488 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4489
4490 return 1; // RADIUS OK and IP allocated, done...
4491 }
4492
4493 //
4494 // This session just got dropped on us by the master or something.
4495 // Make sure our tables up up to date...
4496 //
4497 int load_session(sessionidt s, sessiont *new)
4498 {
4499 int i;
4500 int newip = 0;
4501
4502 // Sanity checks.
4503 if (new->ip_pool_index >= MAXIPPOOL ||
4504 new->tunnel >= MAXTUNNEL)
4505 {
4506 LOG(0, s, 0, "Strange session update received!\n");
4507 // FIXME! What to do here?
4508 return 0;
4509 }
4510
4511 //
4512 // Ok. All sanity checks passed. Now we're committed to
4513 // loading the new session.
4514 //
4515
4516 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4517
4518 // See if routes/ip cache need updating
4519 if (new->ip != session[s].ip)
4520 newip++;
4521
4522 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4523 if (new->route[i].ip != session[s].route[i].ip ||
4524 new->route[i].mask != session[s].route[i].mask)
4525 newip++;
4526
4527 // needs update
4528 if (newip)
4529 {
4530 int routed = 0;
4531
4532 // remove old routes...
4533 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4534 {
4535 if ((session[s].ip & session[s].route[i].mask) ==
4536 (session[s].route[i].ip & session[s].route[i].mask))
4537 routed++;
4538
4539 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4540 }
4541
4542 // ...ip
4543 if (session[s].ip)
4544 {
4545 if (session[s].ip_pool_index == -1) // static IP
4546 {
4547 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4548 }
4549 else // It's part of the IP pool, remove it manually.
4550 uncache_ipmap(session[s].ip);
4551 }
4552
4553 routed = 0;
4554
4555 // add new routes...
4556 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4557 {
4558 if ((new->ip & new->route[i].mask) ==
4559 (new->route[i].ip & new->route[i].mask))
4560 routed++;
4561
4562 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4563 }
4564
4565 // ...ip
4566 if (new->ip)
4567 {
4568 // If there's a new one, add it.
4569 if (new->ip_pool_index == -1)
4570 {
4571 if (!routed) routeset(s, new->ip, 0, 0, 1);
4572 }
4573 else
4574 cache_ipmap(new->ip, s);
4575 }
4576 }
4577
4578 // check v6 routing
4579 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4580 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4581
4582 // check filters
4583 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4584 {
4585 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4586 new->filter_in = 0;
4587 }
4588
4589 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4590 {
4591 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4592 new->filter_out = 0;
4593 }
4594
4595 if (new->filter_in != session[s].filter_in)
4596 {
4597 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4598 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4599 }
4600
4601 if (new->filter_out != session[s].filter_out)
4602 {
4603 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4604 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4605 }
4606
4607 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4608 // for walking the sessions to forward byte counts to the master.
4609 config->cluster_highest_sessionid = s;
4610
4611 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4612
4613 // Do fixups into address pool.
4614 if (new->ip_pool_index != -1)
4615 fix_address_pool(s);
4616
4617 return 1;
4618 }
4619
4620 static void initplugins()
4621 {
4622 int i;
4623
4624 loaded_plugins = ll_init();
4625 // Initialize the plugins to nothing
4626 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4627 plugins[i] = ll_init();
4628 }
4629
4630 static void *open_plugin(char *plugin_name, int load)
4631 {
4632 char path[256] = "";
4633
4634 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4635 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4636 return dlopen(path, RTLD_NOW);
4637 }
4638
4639 // plugin callback to get a config value
4640 static void *getconfig(char *key, enum config_typet type)
4641 {
4642 int i;
4643
4644 for (i = 0; config_values[i].key; i++)
4645 {
4646 if (!strcmp(config_values[i].key, key))
4647 {
4648 if (config_values[i].type == type)
4649 return ((void *) config) + config_values[i].offset;
4650
4651 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4652 key, type, config_values[i].type);
4653
4654 return 0;
4655 }
4656 }
4657
4658 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4659 return 0;
4660 }
4661
4662 static int add_plugin(char *plugin_name)
4663 {
4664 static struct pluginfuncs funcs = {
4665 _log,
4666 _log_hex,
4667 fmtaddr,
4668 sessionbyuser,
4669 sessiontbysessionidt,
4670 sessionidtbysessiont,
4671 radiusnew,
4672 radiussend,
4673 getconfig,
4674 sessionshutdown,
4675 sessionkill,
4676 throttle_session,
4677 cluster_send_session,
4678 };
4679
4680 void *p = open_plugin(plugin_name, 1);
4681 int (*initfunc)(struct pluginfuncs *);
4682 int i;
4683
4684 if (!p)
4685 {
4686 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4687 return -1;
4688 }
4689
4690 if (ll_contains(loaded_plugins, p))
4691 {
4692 dlclose(p);
4693 return 0; // already loaded
4694 }
4695
4696 {
4697 int *v = dlsym(p, "plugin_api_version");
4698 if (!v || *v != PLUGIN_API_VERSION)
4699 {
4700 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4701 dlclose(p);
4702 return -1;
4703 }
4704 }
4705
4706 if ((initfunc = dlsym(p, "plugin_init")))
4707 {
4708 if (!initfunc(&funcs))
4709 {
4710 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4711 dlclose(p);
4712 return -1;
4713 }
4714 }
4715
4716 ll_push(loaded_plugins, p);
4717
4718 for (i = 0; i < max_plugin_functions; i++)
4719 {
4720 void *x;
4721 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4722 {
4723 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4724 ll_push(plugins[i], x);
4725 }
4726 }
4727
4728 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4729 return 1;
4730 }
4731
4732 static void run_plugin_done(void *plugin)
4733 {
4734 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4735
4736 if (donefunc)
4737 donefunc();
4738 }
4739
4740 static int remove_plugin(char *plugin_name)
4741 {
4742 void *p = open_plugin(plugin_name, 0);
4743 int loaded = 0;
4744
4745 if (!p)
4746 return -1;
4747
4748 if (ll_contains(loaded_plugins, p))
4749 {
4750 int i;
4751 for (i = 0; i < max_plugin_functions; i++)
4752 {
4753 void *x;
4754 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4755 ll_delete(plugins[i], x);
4756 }
4757
4758 ll_delete(loaded_plugins, p);
4759 run_plugin_done(p);
4760 loaded = 1;
4761 }
4762
4763 dlclose(p);
4764 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4765 return loaded;
4766 }
4767
4768 int run_plugins(int plugin_type, void *data)
4769 {
4770 int (*func)(void *data);
4771
4772 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4773 return PLUGIN_RET_ERROR;
4774
4775 ll_reset(plugins[plugin_type]);
4776 while ((func = ll_next(plugins[plugin_type])))
4777 {
4778 int r = func(data);
4779
4780 if (r != PLUGIN_RET_OK)
4781 return r; // stop here
4782 }
4783
4784 return PLUGIN_RET_OK;
4785 }
4786
4787 static void plugins_done()
4788 {
4789 void *p;
4790
4791 ll_reset(loaded_plugins);
4792 while ((p = ll_next(loaded_plugins)))
4793 run_plugin_done(p);
4794 }
4795
4796 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4797 {
4798 struct nsctl request;
4799 struct nsctl response;
4800 int type = unpack_control(&request, buf, len);
4801 int r;
4802 void *p;
4803
4804 if (log_stream && config->debug >= 4)
4805 {
4806 if (type < 0)
4807 {
4808 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4809 fmtaddr(addr->sin_addr.s_addr, 0), type);
4810 }
4811 else
4812 {
4813 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4814 dump_control(&request, log_stream);
4815 }
4816 }
4817
4818 switch (type)
4819 {
4820 case NSCTL_REQ_LOAD:
4821 if (request.argc != 1)
4822 {
4823 response.type = NSCTL_RES_ERR;
4824 response.argc = 1;
4825 response.argv[0] = "name of plugin required";
4826 }
4827 else if ((r = add_plugin(request.argv[0])) < 1)
4828 {
4829 response.type = NSCTL_RES_ERR;
4830 response.argc = 1;
4831 response.argv[0] = !r
4832 ? "plugin already loaded"
4833 : "error loading plugin";
4834 }
4835 else
4836 {
4837 response.type = NSCTL_RES_OK;
4838 response.argc = 0;
4839 }
4840
4841 break;
4842
4843 case NSCTL_REQ_UNLOAD:
4844 if (request.argc != 1)
4845 {
4846 response.type = NSCTL_RES_ERR;
4847 response.argc = 1;
4848 response.argv[0] = "name of plugin required";
4849 }
4850 else if ((r = remove_plugin(request.argv[0])) < 1)
4851 {
4852 response.type = NSCTL_RES_ERR;
4853 response.argc = 1;
4854 response.argv[0] = !r
4855 ? "plugin not loaded"
4856 : "plugin not found";
4857 }
4858 else
4859 {
4860 response.type = NSCTL_RES_OK;
4861 response.argc = 0;
4862 }
4863
4864 break;
4865
4866 case NSCTL_REQ_HELP:
4867 response.type = NSCTL_RES_OK;
4868 response.argc = 0;
4869
4870 ll_reset(loaded_plugins);
4871 while ((p = ll_next(loaded_plugins)))
4872 {
4873 char **help = dlsym(p, "plugin_control_help");
4874 while (response.argc < 0xff && help && *help)
4875 response.argv[response.argc++] = *help++;
4876 }
4877
4878 break;
4879
4880 case NSCTL_REQ_CONTROL:
4881 {
4882 struct param_control param = {
4883 config->cluster_iam_master,
4884 request.argc,
4885 request.argv,
4886 0,
4887 NULL,
4888 };
4889
4890 int r = run_plugins(PLUGIN_CONTROL, &param);
4891
4892 if (r == PLUGIN_RET_ERROR)
4893 {
4894 response.type = NSCTL_RES_ERR;
4895 response.argc = 1;
4896 response.argv[0] = param.additional
4897 ? param.additional
4898 : "error returned by plugin";
4899 }
4900 else if (r == PLUGIN_RET_NOTMASTER)
4901 {
4902 static char msg[] = "must be run on master: 000.000.000.000";
4903
4904 response.type = NSCTL_RES_ERR;
4905 response.argc = 1;
4906 if (config->cluster_master_address)
4907 {
4908 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4909 response.argv[0] = msg;
4910 }
4911 else
4912 {
4913 response.argv[0] = "must be run on master: none elected";
4914 }
4915 }
4916 else if (!(param.response & NSCTL_RESPONSE))
4917 {
4918 response.type = NSCTL_RES_ERR;
4919 response.argc = 1;
4920 response.argv[0] = param.response
4921 ? "unrecognised response value from plugin"
4922 : "unhandled action";
4923 }
4924 else
4925 {
4926 response.type = param.response;
4927 response.argc = 0;
4928 if (param.additional)
4929 {
4930 response.argc = 1;
4931 response.argv[0] = param.additional;
4932 }
4933 }
4934 }
4935
4936 break;
4937
4938 default:
4939 response.type = NSCTL_RES_ERR;
4940 response.argc = 1;
4941 response.argv[0] = "error unpacking control packet";
4942 }
4943
4944 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4945 if (!buf)
4946 {
4947 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4948 return;
4949 }
4950
4951 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4952 if (r > 0)
4953 {
4954 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4955 if (log_stream && config->debug >= 4)
4956 {
4957 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4958 dump_control(&response, log_stream);
4959 }
4960 }
4961 else
4962 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4963 fmtaddr(addr->sin_addr.s_addr, 0), r);
4964
4965 free(buf);
4966 }
4967
4968 static tunnelidt new_tunnel()
4969 {
4970 tunnelidt i;
4971 for (i = 1; i < MAXTUNNEL; i++)
4972 {
4973 if (tunnel[i].state == TUNNELFREE)
4974 {
4975 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4976 if (i > config->cluster_highest_tunnelid)
4977 config->cluster_highest_tunnelid = i;
4978 return i;
4979 }
4980 }
4981 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4982 return 0;
4983 }
4984
4985 //
4986 // We're becoming the master. Do any required setup..
4987 //
4988 // This is principally telling all the plugins that we're
4989 // now a master, and telling them about all the sessions
4990 // that are active too..
4991 //
4992 void become_master(void)
4993 {
4994 int s, i;
4995 static struct event_data d[RADIUS_FDS];
4996 struct epoll_event e;
4997
4998 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4999
5000 // running a bunch of iptables commands is slow and can cause
5001 // the master to drop tunnels on takeover--kludge around the
5002 // problem by forking for the moment (note: race)
5003 if (!fork_and_close())
5004 {
5005 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5006 {
5007 if (!session[s].opened) // Not an in-use session.
5008 continue;
5009
5010 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5011 }
5012 exit(0);
5013 }
5014
5015 // add radius fds
5016 e.events = EPOLLIN;
5017 for (i = 0; i < RADIUS_FDS; i++)
5018 {
5019 d[i].type = FD_TYPE_RADIUS;
5020 d[i].index = i;
5021 e.data.ptr = &d[i];
5022
5023 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5024 }
5025 }
5026
5027 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5028 {
5029 int s, i;
5030 int count = 0;
5031 int buckets[64];
5032
5033 if (CLI_HELP_REQUESTED)
5034 return CLI_HELP_NO_ARGS;
5035
5036 time(&time_now);
5037 for (i = 0; i < 64;++i) buckets[i] = 0;
5038
5039 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5040 {
5041 int idle;
5042 if (!session[s].opened)
5043 continue;
5044
5045 idle = time_now - session[s].last_packet;
5046 idle /= 5 ; // In multiples of 5 seconds.
5047 if (idle < 0)
5048 idle = 0;
5049 if (idle > 63)
5050 idle = 63;
5051
5052 ++count;
5053 ++buckets[idle];
5054 }
5055
5056 for (i = 0; i < 63; ++i)
5057 {
5058 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5059 }
5060 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5061 cli_print(cli, "%d total sessions open.", count);
5062 return CLI_OK;
5063 }
5064
5065 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5066 {
5067 int s, i;
5068 int count = 0;
5069 int buckets[64];
5070
5071 if (CLI_HELP_REQUESTED)
5072 return CLI_HELP_NO_ARGS;
5073
5074 time(&time_now);
5075 for (i = 0; i < 64;++i) buckets[i] = 0;
5076
5077 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5078 {
5079 int open = 0, d;
5080 if (!session[s].opened)
5081 continue;
5082
5083 d = time_now - session[s].opened;
5084 if (d < 0)
5085 d = 0;
5086 while (d > 1 && open < 32)
5087 {
5088 ++open;
5089 d >>= 1; // half.
5090 }
5091 ++count;
5092 ++buckets[open];
5093 }
5094
5095 s = 1;
5096 for (i = 0; i < 30; ++i)
5097 {
5098 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5099 s <<= 1;
5100 }
5101 cli_print(cli, "%d total sessions open.", count);
5102 return CLI_OK;
5103 }
5104
5105 /* Unhide an avp.
5106 *
5107 * This unencodes the AVP using the L2TP secret and the previously
5108 * stored random vector. It overwrites the hidden data with the
5109 * unhidden AVP subformat.
5110 */
5111 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5112 {
5113 MD5_CTX ctx;
5114 uint8_t digest[16];
5115 uint8_t *last;
5116 size_t d = 0;
5117 uint16_t m = htons(type);
5118
5119 // Compute initial pad
5120 MD5_Init(&ctx);
5121 MD5_Update(&ctx, (unsigned char *) &m, 2);
5122 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5123 MD5_Update(&ctx, vector, vec_len);
5124 MD5_Final(digest, &ctx);
5125
5126 // pointer to last decoded 16 octets
5127 last = value;
5128
5129 while (len > 0)
5130 {
5131 // calculate a new pad based on the last decoded block
5132 if (d >= sizeof(digest))
5133 {
5134 MD5_Init(&ctx);
5135 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5136 MD5_Update(&ctx, last, sizeof(digest));
5137 MD5_Final(digest, &ctx);
5138
5139 d = 0;
5140 last = value;
5141 }
5142
5143 *value++ ^= digest[d++];
5144 len--;
5145 }
5146 }
5147
5148 int find_filter(char const *name, size_t len)
5149 {
5150 int free = -1;
5151 int i;
5152
5153 for (i = 0; i < MAXFILTER; i++)
5154 {
5155 if (!*ip_filters[i].name)
5156 {
5157 if (free < 0)
5158 free = i;
5159
5160 continue;
5161 }
5162
5163 if (strlen(ip_filters[i].name) != len)
5164 continue;
5165
5166 if (!strncmp(ip_filters[i].name, name, len))
5167 return i;
5168 }
5169
5170 return free;
5171 }
5172
5173 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5174 {
5175 switch (p->op)
5176 {
5177 case FILTER_PORT_OP_EQ: return port == p->port;
5178 case FILTER_PORT_OP_NEQ: return port != p->port;
5179 case FILTER_PORT_OP_GT: return port > p->port;
5180 case FILTER_PORT_OP_LT: return port < p->port;
5181 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5182 }
5183
5184 return 0;
5185 }
5186
5187 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5188 {
5189 switch (op)
5190 {
5191 case FILTER_FLAG_OP_ANY:
5192 return (flags & sflags) || (~flags & cflags);
5193
5194 case FILTER_FLAG_OP_ALL:
5195 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5196
5197 case FILTER_FLAG_OP_EST:
5198 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5199 }
5200
5201 return 0;
5202 }
5203
5204 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5205 {
5206 uint16_t frag_offset;
5207 uint8_t proto;
5208 in_addr_t src_ip;
5209 in_addr_t dst_ip;
5210 uint16_t src_port = 0;
5211 uint16_t dst_port = 0;
5212 uint8_t flags = 0;
5213 ip_filter_rulet *rule;
5214
5215 if (len < 20) // up to end of destination address
5216 return 0;
5217
5218 if ((*buf >> 4) != 4) // IPv4
5219 return 0;
5220
5221 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5222 proto = buf[9];
5223 src_ip = *(in_addr_t *) (buf + 12);
5224 dst_ip = *(in_addr_t *) (buf + 16);
5225
5226 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5227 {
5228 int l = (buf[0] & 0xf) * 4; // length of IP header
5229 if (len < l + 4) // ports
5230 return 0;
5231
5232 src_port = ntohs(*(uint16_t *) (buf + l));
5233 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5234 if (proto == IPPROTO_TCP)
5235 {
5236 if (len < l + 14) // flags
5237 return 0;
5238
5239 flags = buf[l + 13] & 0x3f;
5240 }
5241 }
5242
5243 for (rule = ip_filters[filter].rules; rule->action; rule++)
5244 {
5245 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5246 continue;
5247
5248 if (rule->src_wild != INADDR_BROADCAST &&
5249 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5250 continue;
5251
5252 if (rule->dst_wild != INADDR_BROADCAST &&
5253 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5254 continue;
5255
5256 if (frag_offset)
5257 {
5258 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5259 continue;
5260 }
5261 else
5262 {
5263 if (rule->frag)
5264 continue;
5265
5266 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5267 {
5268 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5269 continue;
5270
5271 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5272 continue;
5273
5274 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5275 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5276 continue;
5277 }
5278 }
5279
5280 // matched
5281 rule->counter++;
5282 return rule->action == FILTER_ACTION_PERMIT;
5283 }
5284
5285 // default deny
5286 return 0;
5287 }