6effc9f238176613376f206fa83e81c3f416821f
[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 1.149 2005/11/17 06:46:24 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 // calculated from config->l2tp_mtu
79 uint16_t MRU = 0; // PPP MRU
80 uint16_t MSS = 0; // TCP MSS
81
82 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
83 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
84
85 static void *ip_hash[256]; // Mapping from IP address to session structures.
86 struct ipv6radix {
87 int sess;
88 struct ipv6radix *branch;
89 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
90
91 // Traffic counters.
92 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
93 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
94 uint32_t eth_tx = 0;
95
96 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
97 time_t time_now = 0; // Current time in seconds since epoch.
98 static char time_now_string[64] = {0}; // Current time as a string.
99 int time_changed = 0; // time_now changed
100 char main_quit = 0; // True if we're in the process of exiting.
101 char main_reload = 0; // Re-load pending
102 linked_list *loaded_plugins;
103 linked_list *plugins[MAX_PLUGIN_TYPES];
104
105 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
106 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
107
108 config_descriptt config_values[] = {
109 CONFIG("debug", debug, INT),
110 CONFIG("log_file", log_filename, STRING),
111 CONFIG("pid_file", pid_file, STRING),
112 CONFIG("random_device", random_device, STRING),
113 CONFIG("l2tp_secret", l2tp_secret, STRING),
114 CONFIG("l2tp_mtu", l2tp_mtu, INT),
115 CONFIG("ppp_restart_time", ppp_restart_time, INT),
116 CONFIG("ppp_max_configure", ppp_max_configure, INT),
117 CONFIG("ppp_max_failure", ppp_max_failure, INT),
118 CONFIG("primary_dns", default_dns1, IPv4),
119 CONFIG("secondary_dns", default_dns2, IPv4),
120 CONFIG("primary_radius", radiusserver[0], IPv4),
121 CONFIG("secondary_radius", radiusserver[1], IPv4),
122 CONFIG("primary_radius_port", radiusport[0], SHORT),
123 CONFIG("secondary_radius_port", radiusport[1], SHORT),
124 CONFIG("radius_accounting", radius_accounting, BOOL),
125 CONFIG("radius_interim", radius_interim, INT),
126 CONFIG("radius_secret", radiussecret, STRING),
127 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
128 CONFIG("radius_dae_port", radius_dae_port, SHORT),
129 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
130 CONFIG("bind_address", bind_address, IPv4),
131 CONFIG("peer_address", peer_address, IPv4),
132 CONFIG("send_garp", send_garp, BOOL),
133 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
134 CONFIG("throttle_buckets", num_tbfs, INT),
135 CONFIG("accounting_dir", accounting_dir, STRING),
136 CONFIG("setuid", target_uid, INT),
137 CONFIG("dump_speed", dump_speed, BOOL),
138 CONFIG("multi_read_count", multi_read_count, INT),
139 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
140 CONFIG("lock_pages", lock_pages, BOOL),
141 CONFIG("icmp_rate", icmp_rate, INT),
142 CONFIG("packet_limit", max_packets, INT),
143 CONFIG("cluster_address", cluster_address, IPv4),
144 CONFIG("cluster_interface", cluster_interface, STRING),
145 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
146 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
147 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
148 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
149 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
150 { NULL, 0, 0, 0 },
151 };
152
153 static char *plugin_functions[] = {
154 NULL,
155 "plugin_pre_auth",
156 "plugin_post_auth",
157 "plugin_packet_rx",
158 "plugin_packet_tx",
159 "plugin_timer",
160 "plugin_new_session",
161 "plugin_kill_session",
162 "plugin_control",
163 "plugin_radius_response",
164 "plugin_radius_reset",
165 "plugin_radius_account",
166 "plugin_become_master",
167 "plugin_new_session_master",
168 };
169
170 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
171
172 // Counters for shutdown sessions
173 static sessiont shut_acct[8192];
174 static sessionidt shut_acct_n = 0;
175
176 tunnelt *tunnel = NULL; // Array of tunnel structures.
177 sessiont *session = NULL; // Array of session structures.
178 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
179 radiust *radius = NULL; // Array of radius structures.
180 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
181 ip_filtert *ip_filters = NULL; // Array of named filters.
182 static controlt *controlfree = 0;
183 struct Tstats *_statistics = NULL;
184 #ifdef RINGBUFFER
185 struct Tringbuffer *ringbuffer = NULL;
186 #endif
187
188 static void cache_ipmap(in_addr_t ip, int s);
189 static void uncache_ipmap(in_addr_t ip);
190 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
191 static void free_ip_address(sessionidt s);
192 static void dump_acct_info(int all);
193 static void sighup_handler(int sig);
194 static void shutdown_handler(int sig);
195 static void sigchild_handler(int sig);
196 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
197 static void update_config(void);
198 static void read_config_file(void);
199 static void initplugins(void);
200 static int add_plugin(char *plugin_name);
201 static int remove_plugin(char *plugin_name);
202 static void plugins_done(void);
203 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
204 static tunnelidt new_tunnel(void);
205 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
206
207 // on slaves, alow BGP to withdraw cleanly before exiting
208 #define QUIT_DELAY 5
209
210 // quit actions (master)
211 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
212 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
213
214 // return internal time (10ths since process startup), set f if given
215 // as a side-effect sets time_now, and time_changed
216 static clockt now(double *f)
217 {
218 struct timeval t;
219 gettimeofday(&t, 0);
220 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
221 if (t.tv_sec != time_now)
222 {
223 time_now = t.tv_sec;
224 time_changed++;
225 }
226 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
227 }
228
229 // work out a retry time based on try number
230 // This is a straight bounded exponential backoff.
231 // Maximum re-try time is 32 seconds. (2^5).
232 clockt backoff(uint8_t try)
233 {
234 if (try > 5) try = 5; // max backoff
235 return now(NULL) + 10 * (1 << try);
236 }
237
238
239 //
240 // Log a debug message. Typically called via the LOG macro
241 //
242 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
243 {
244 static char message[65536] = {0};
245 va_list ap;
246
247 #ifdef RINGBUFFER
248 if (ringbuffer)
249 {
250 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
251 ringbuffer->tail = 0;
252 if (ringbuffer->tail == ringbuffer->head)
253 if (++ringbuffer->head >= RINGBUFFER_SIZE)
254 ringbuffer->head = 0;
255
256 ringbuffer->buffer[ringbuffer->tail].level = level;
257 ringbuffer->buffer[ringbuffer->tail].session = s;
258 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
259 va_start(ap, format);
260 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
261 va_end(ap);
262 }
263 #endif
264
265 if (config->debug < level) return;
266
267 va_start(ap, format);
268 vsnprintf(message, sizeof(message), format, ap);
269
270 if (log_stream)
271 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
272 else if (syslog_log)
273 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
274
275 va_end(ap);
276 }
277
278 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
279 {
280 int i, j;
281 const uint8_t *d = data;
282
283 if (config->debug < level) return;
284
285 // No support for _log_hex to syslog
286 if (log_stream)
287 {
288 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
289 setvbuf(log_stream, NULL, _IOFBF, 16384);
290
291 for (i = 0; i < maxsize; )
292 {
293 fprintf(log_stream, "%4X: ", i);
294 for (j = i; j < maxsize && j < (i + 16); j++)
295 {
296 fprintf(log_stream, "%02X ", d[j]);
297 if (j == i + 7)
298 fputs(": ", log_stream);
299 }
300
301 for (; j < i + 16; j++)
302 {
303 fputs(" ", log_stream);
304 if (j == i + 7)
305 fputs(": ", log_stream);
306 }
307
308 fputs(" ", log_stream);
309 for (j = i; j < maxsize && j < (i + 16); j++)
310 {
311 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
312 fputc(d[j], log_stream);
313 else
314 fputc('.', log_stream);
315
316 if (j == i + 7)
317 fputs(" ", log_stream);
318 }
319
320 i = j;
321 fputs("\n", log_stream);
322 }
323
324 fflush(log_stream);
325 setbuf(log_stream, NULL);
326 }
327 }
328
329 // update a counter, accumulating 2^32 wraps
330 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
331 {
332 uint32_t new = *counter + delta;
333 if (new < *counter)
334 (*wrap)++;
335
336 *counter = new;
337 }
338
339 // initialise the random generator
340 static void initrandom(char *source)
341 {
342 static char path[sizeof(config->random_device)] = "*undefined*";
343
344 // reinitialise only if we are forced to do so or if the config has changed
345 if (source && !strncmp(path, source, sizeof(path)))
346 return;
347
348 // close previous source, if any
349 if (rand_fd >= 0)
350 close(rand_fd);
351
352 rand_fd = -1;
353
354 if (source)
355 {
356 // register changes
357 snprintf(path, sizeof(path), "%s", source);
358
359 if (*path == '/')
360 {
361 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
362 if (rand_fd < 0)
363 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
364 path, strerror(errno));
365 }
366 }
367 }
368
369 // fill buffer with random data
370 void random_data(uint8_t *buf, int len)
371 {
372 int n = 0;
373
374 CSTAT(random_data);
375 if (rand_fd >= 0)
376 {
377 n = read(rand_fd, buf, len);
378 if (n >= len) return;
379 if (n < 0)
380 {
381 if (errno != EAGAIN)
382 {
383 LOG(0, 0, 0, "Error reading from random source: %s\n",
384 strerror(errno));
385
386 // fall back to rand()
387 initrandom(NULL);
388 }
389
390 n = 0;
391 }
392 }
393
394 // append missing data
395 while (n < len)
396 // not using the low order bits from the prng stream
397 buf[n++] = (rand() >> 4) & 0xff;
398 }
399
400 // Add a route
401 //
402 // This adds it to the routing table, advertises it
403 // via BGP if enabled, and stuffs it into the
404 // 'sessionbyip' cache.
405 //
406 // 'ip' and 'mask' must be in _host_ order.
407 //
408 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
409 {
410 struct rtentry r;
411 int i;
412
413 if (!mask) mask = 0xffffffff;
414
415 ip &= mask; // Force the ip to be the first one in the route.
416
417 memset(&r, 0, sizeof(r));
418 r.rt_dev = config->tundevice;
419 r.rt_dst.sa_family = AF_INET;
420 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
421 r.rt_gateway.sa_family = AF_INET;
422 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
423 r.rt_genmask.sa_family = AF_INET;
424 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
425 r.rt_flags = (RTF_UP | RTF_STATIC);
426 if (gw)
427 r.rt_flags |= RTF_GATEWAY;
428 else if (mask == 0xffffffff)
429 r.rt_flags |= RTF_HOST;
430
431 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
432 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
433 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
434
435 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
436 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
437
438 #ifdef BGP
439 if (add)
440 bgp_add_route(htonl(ip), htonl(mask));
441 else
442 bgp_del_route(htonl(ip), htonl(mask));
443 #endif /* BGP */
444
445 // Add/Remove the IPs to the 'sessionbyip' cache.
446 // Note that we add the zero address in the case of
447 // a network route. Roll on CIDR.
448
449 // Note that 's == 0' implies this is the address pool.
450 // We still cache it here, because it will pre-fill
451 // the malloc'ed tree.
452
453 if (s)
454 {
455 if (!add) // Are we deleting a route?
456 s = 0; // Caching the session as '0' is the same as uncaching.
457
458 for (i = ip; (i&mask) == (ip&mask) ; ++i)
459 cache_ipmap(i, s);
460 }
461 }
462
463 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
464 {
465 struct in6_rtmsg rt;
466 char ipv6addr[INET6_ADDRSTRLEN];
467
468 if (ifr6fd < 0)
469 {
470 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
471 return;
472 }
473
474 memset(&rt, 0, sizeof(rt));
475
476 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
477 rt.rtmsg_dst_len = prefixlen;
478 rt.rtmsg_metric = 1;
479 rt.rtmsg_flags = RTF_UP;
480 rt.rtmsg_ifindex = tunidx;
481
482 LOG(1, 0, 0, "Route %s %s/%d\n",
483 add ? "add" : "del",
484 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
485 prefixlen);
486
487 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
488 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
489 strerror(errno));
490
491 // FIXME: need to add BGP routing (RFC2858)
492
493 if (s)
494 {
495 if (!add) // Are we deleting a route?
496 s = 0; // Caching the session as '0' is the same as uncaching.
497
498 cache_ipv6map(ip, prefixlen, s);
499 }
500
501 return;
502 }
503
504 // defined in linux/ipv6.h, but tricky to include from user-space
505 // TODO: move routing to use netlink rather than ioctl
506 struct in6_ifreq {
507 struct in6_addr ifr6_addr;
508 __u32 ifr6_prefixlen;
509 unsigned int ifr6_ifindex;
510 };
511
512 //
513 // Set up TUN interface
514 static void inittun(void)
515 {
516 struct ifreq ifr;
517 struct in6_ifreq ifr6;
518 struct sockaddr_in sin = {0};
519 memset(&ifr, 0, sizeof(ifr));
520 ifr.ifr_flags = IFF_TUN;
521
522 tunfd = open(TUNDEVICE, O_RDWR);
523 if (tunfd < 0)
524 { // fatal
525 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
526 exit(1);
527 }
528 {
529 int flags = fcntl(tunfd, F_GETFL, 0);
530 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
531 }
532 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
533 {
534 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
535 exit(1);
536 }
537 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
538 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
539 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
540
541 sin.sin_family = AF_INET;
542 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
543 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
544
545 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
546 {
547 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
548 exit(1);
549 }
550 /* Bump up the qlen to deal with bursts from the network */
551 ifr.ifr_qlen = 1000;
552 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
553 {
554 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
555 exit(1);
556 }
557 ifr.ifr_flags = IFF_UP;
558 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
559 {
560 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
561 exit(1);
562 }
563 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
564 {
565 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
566 exit(1);
567 }
568 tunidx = ifr.ifr_ifindex;
569
570 // Only setup IPv6 on the tun device if we have a configured prefix
571 if (config->ipv6_prefix.s6_addr[0]) {
572 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
573
574 // Link local address is FE80::1
575 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
576 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
577 ifr6.ifr6_addr.s6_addr[1] = 0x80;
578 ifr6.ifr6_addr.s6_addr[15] = 1;
579 ifr6.ifr6_prefixlen = 64;
580 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
581 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
582 {
583 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
584 " %s\n", strerror(errno));
585 }
586
587 // Global address is prefix::1
588 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
589 ifr6.ifr6_addr = config->ipv6_prefix;
590 ifr6.ifr6_addr.s6_addr[15] = 1;
591 ifr6.ifr6_prefixlen = 64;
592 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
593 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
594 {
595 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
596 strerror(errno));
597 }
598 }
599 }
600
601 // set up UDP ports
602 static void initudp(void)
603 {
604 int on = 1;
605 struct sockaddr_in addr;
606
607 // Tunnel
608 memset(&addr, 0, sizeof(addr));
609 addr.sin_family = AF_INET;
610 addr.sin_port = htons(L2TPPORT);
611 addr.sin_addr.s_addr = config->bind_address;
612 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
613 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
614 {
615 int flags = fcntl(udpfd, F_GETFL, 0);
616 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
617 }
618 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
619 {
620 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
621 exit(1);
622 }
623
624 // Control
625 memset(&addr, 0, sizeof(addr));
626 addr.sin_family = AF_INET;
627 addr.sin_port = htons(NSCTL_PORT);
628 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
629 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
630 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
631 {
632 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
633 exit(1);
634 }
635
636 // Dynamic Authorization Extensions to RADIUS
637 memset(&addr, 0, sizeof(addr));
638 addr.sin_family = AF_INET;
639 addr.sin_port = htons(config->radius_dae_port);
640 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
641 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
642 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
643 {
644 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
645 exit(1);
646 }
647
648 // Intercept
649 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
650 }
651
652 //
653 // Find session by IP, < 1 for not found
654 //
655 // Confusingly enough, this 'ip' must be
656 // in _network_ order. This being the common
657 // case when looking it up from IP packet headers.
658 //
659 // We actually use this cache for two things.
660 // #1. For used IP addresses, this maps to the
661 // session ID that it's used by.
662 // #2. For un-used IP addresses, this maps to the
663 // index into the pool table that contains that
664 // IP address.
665 //
666
667 static int lookup_ipmap(in_addr_t ip)
668 {
669 uint8_t *a = (uint8_t *) &ip;
670 uint8_t **d = (uint8_t **) ip_hash;
671
672 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
673 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
674 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
675
676 return (int) (intptr_t) d[(size_t) *a];
677 }
678
679 static int lookup_ipv6map(struct in6_addr ip)
680 {
681 struct ipv6radix *curnode;
682 int i;
683 int s;
684 char ipv6addr[INET6_ADDRSTRLEN];
685
686 curnode = &ipv6_hash[ip.s6_addr[0]];
687 i = 1;
688 s = curnode->sess;
689
690 while (s == 0 && i < 15 && curnode->branch != NULL)
691 {
692 curnode = &curnode->branch[ip.s6_addr[i]];
693 s = curnode->sess;
694 i++;
695 }
696
697 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
698 inet_ntop(AF_INET6, &ip, ipv6addr,
699 INET6_ADDRSTRLEN),
700 s);
701
702 return s;
703 }
704
705 sessionidt sessionbyip(in_addr_t ip)
706 {
707 int s = lookup_ipmap(ip);
708 CSTAT(sessionbyip);
709
710 if (s > 0 && s < MAXSESSION && session[s].opened)
711 return (sessionidt) s;
712
713 return 0;
714 }
715
716 sessionidt sessionbyipv6(struct in6_addr ip)
717 {
718 int s;
719 CSTAT(sessionbyipv6);
720
721 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
722 (ip.s6_addr[0] == 0xFE &&
723 ip.s6_addr[1] == 0x80 &&
724 ip.s6_addr16[1] == 0 &&
725 ip.s6_addr16[2] == 0 &&
726 ip.s6_addr16[3] == 0)) {
727 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
728 } else {
729 s = lookup_ipv6map(ip);
730 }
731
732 if (s > 0 && s < MAXSESSION && session[s].opened)
733 return s;
734
735 return 0;
736 }
737
738 //
739 // Take an IP address in HOST byte order and
740 // add it to the sessionid by IP cache.
741 //
742 // (It's actually cached in network order)
743 //
744 static void cache_ipmap(in_addr_t ip, int s)
745 {
746 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
747 uint8_t *a = (uint8_t *) &nip;
748 uint8_t **d = (uint8_t **) ip_hash;
749 int i;
750
751 for (i = 0; i < 3; i++)
752 {
753 if (!d[(size_t) a[i]])
754 {
755 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
756 return;
757 }
758
759 d = (uint8_t **) d[(size_t) a[i]];
760 }
761
762 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
763
764 if (s > 0)
765 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
766
767 else if (s == 0)
768 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
769 // else a map to an ip pool index.
770 }
771
772 static void uncache_ipmap(in_addr_t ip)
773 {
774 cache_ipmap(ip, 0); // Assign it to the NULL session.
775 }
776
777 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
778 {
779 int i;
780 int bytes;
781 struct ipv6radix *curnode;
782 char ipv6addr[INET6_ADDRSTRLEN];
783
784 curnode = &ipv6_hash[ip.s6_addr[0]];
785
786 bytes = prefixlen >> 3;
787 i = 1;
788 while (i < bytes) {
789 if (curnode->branch == NULL)
790 {
791 if (!(curnode->branch = calloc(256,
792 sizeof (struct ipv6radix))))
793 return;
794 }
795 curnode = &curnode->branch[ip.s6_addr[i]];
796 i++;
797 }
798
799 curnode->sess = s;
800
801 if (s > 0)
802 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
803 inet_ntop(AF_INET6, &ip, ipv6addr,
804 INET6_ADDRSTRLEN),
805 prefixlen);
806 else if (s == 0)
807 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
808 inet_ntop(AF_INET6, &ip, ipv6addr,
809 INET6_ADDRSTRLEN),
810 prefixlen);
811 }
812
813 //
814 // CLI list to dump current ipcache.
815 //
816 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
817 {
818 char **d = (char **) ip_hash, **e, **f, **g;
819 int i, j, k, l;
820 int count = 0;
821
822 if (CLI_HELP_REQUESTED)
823 return CLI_HELP_NO_ARGS;
824
825 cli_print(cli, "%7s %s", "Sess#", "IP Address");
826
827 for (i = 0; i < 256; ++i)
828 {
829 if (!d[i])
830 continue;
831 e = (char **) d[i];
832 for (j = 0; j < 256; ++j)
833 {
834 if (!e[j])
835 continue;
836 f = (char **) e[j];
837 for (k = 0; k < 256; ++k)
838 {
839 if (!f[k])
840 continue;
841 g = (char **)f[k];
842 for (l = 0; l < 256; ++l)
843 {
844 if (!g[l])
845 continue;
846 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
847 ++count;
848 }
849 }
850 }
851 }
852 cli_print(cli, "%d entries in cache", count);
853 return CLI_OK;
854 }
855
856
857 // Find session by username, 0 for not found
858 // walled garden users aren't authenticated, so the username is
859 // reasonably useless. Ignore them to avoid incorrect actions
860 //
861 // This is VERY inefficent. Don't call it often. :)
862 //
863 sessionidt sessionbyuser(char *username)
864 {
865 int s;
866 CSTAT(sessionbyuser);
867
868 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
869 {
870 if (!session[s].opened)
871 continue;
872
873 if (session[s].walled_garden)
874 continue; // Skip walled garden users.
875
876 if (!strncmp(session[s].user, username, 128))
877 return s;
878
879 }
880 return 0; // Not found.
881 }
882
883 void send_garp(in_addr_t ip)
884 {
885 int s;
886 struct ifreq ifr;
887 uint8_t mac[6];
888
889 s = socket(PF_INET, SOCK_DGRAM, 0);
890 if (s < 0)
891 {
892 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
893 return;
894 }
895 memset(&ifr, 0, sizeof(ifr));
896 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
897 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
898 {
899 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
900 close(s);
901 return;
902 }
903 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
904 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
905 {
906 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
907 close(s);
908 return;
909 }
910 close(s);
911 sendarp(ifr.ifr_ifindex, mac, ip);
912 }
913
914 static sessiont *sessiontbysessionidt(sessionidt s)
915 {
916 if (!s || s >= MAXSESSION) return NULL;
917 return &session[s];
918 }
919
920 static sessionidt sessionidtbysessiont(sessiont *s)
921 {
922 sessionidt val = s-session;
923 if (s < session || val >= MAXSESSION) return 0;
924 return val;
925 }
926
927 // actually send a control message for a specific tunnel
928 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
929 {
930 struct sockaddr_in addr;
931
932 CSTAT(tunnelsend);
933
934 if (!t)
935 {
936 static int backtrace_count = 0;
937 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
938 STAT(tunnel_tx_errors);
939 log_backtrace(backtrace_count, 5)
940 return;
941 }
942
943 if (!tunnel[t].ip)
944 {
945 static int backtrace_count = 0;
946 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
947 log_backtrace(backtrace_count, 5)
948 STAT(tunnel_tx_errors);
949 return;
950 }
951
952 memset(&addr, 0, sizeof(addr));
953 addr.sin_family = AF_INET;
954 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
955 addr.sin_port = htons(tunnel[t].port);
956
957 // sequence expected, if sequence in message
958 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
959
960 // If this is a control message, deal with retries
961 if (*buf & 0x80)
962 {
963 tunnel[t].last = time_now; // control message sent
964 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
965 if (tunnel[t].try)
966 {
967 STAT(tunnel_retries);
968 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
969 }
970 }
971
972 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
973 {
974 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
975 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
976 STAT(tunnel_tx_errors);
977 return;
978 }
979
980 LOG_HEX(5, "Send Tunnel Data", buf, l);
981 STAT(tunnel_tx_packets);
982 INC_STAT(tunnel_tx_bytes, l);
983 }
984
985 //
986 // Tiny helper function to write data to
987 // the 'tun' device.
988 //
989 int tun_write(uint8_t * data, int size)
990 {
991 return write(tunfd, data, size);
992 }
993
994 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
995 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
996 {
997 int d = (tcp[12] >> 4) * 4;
998 uint8_t *mss = 0;
999 uint8_t *opts;
1000 uint8_t *data;
1001 uint16_t orig;
1002 uint32_t sum;
1003
1004 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1005 return;
1006
1007 if (tcp + d > buf + len) // short?
1008 return;
1009
1010 opts = tcp + 20;
1011 data = tcp + d;
1012
1013 while (opts < data)
1014 {
1015 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1016 {
1017 mss = opts + 2;
1018 if (mss + 2 > data) return; // short?
1019 break;
1020 }
1021
1022 if (*opts == 0) return; // end of options
1023 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1024 opts++;
1025 else
1026 opts += opts[1]; // skip over option
1027 }
1028
1029 if (!mss) return; // not found
1030 orig = ntohs(*(uint16_t *) mss);
1031
1032 if (orig <= MSS) return; // mss OK
1033
1034 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1035 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1036 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1037 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1038
1039 // set mss
1040 *(int16_t *) mss = htons(MSS);
1041
1042 // adjust checksum (see rfc1141)
1043 sum = orig + (~MSS & 0xffff);
1044 sum += ntohs(*(uint16_t *) (tcp + 16));
1045 sum = (sum & 0xffff) + (sum >> 16);
1046 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1047 }
1048
1049 // process outgoing (to tunnel) IP
1050 //
1051 static void processipout(uint8_t *buf, int len)
1052 {
1053 sessionidt s;
1054 sessiont *sp;
1055 tunnelidt t;
1056 in_addr_t ip;
1057
1058 uint8_t *data = buf; // Keep a copy of the originals.
1059 int size = len;
1060
1061 uint8_t b[MAXETHER + 20];
1062
1063 CSTAT(processipout);
1064
1065 if (len < MIN_IP_SIZE)
1066 {
1067 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1068 STAT(tun_rx_errors);
1069 return;
1070 }
1071 if (len >= MAXETHER)
1072 {
1073 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1074 STAT(tun_rx_errors);
1075 return;
1076 }
1077
1078 // Skip the tun header
1079 buf += 4;
1080 len -= 4;
1081
1082 // Got an IP header now
1083 if (*(uint8_t *)(buf) >> 4 != 4)
1084 {
1085 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1086 return;
1087 }
1088
1089 ip = *(uint32_t *)(buf + 16);
1090 if (!(s = sessionbyip(ip)))
1091 {
1092 // Is this a packet for a session that doesn't exist?
1093 static int rate = 0; // Number of ICMP packets we've sent this second.
1094 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1095
1096 if (last != time_now)
1097 {
1098 last = time_now;
1099 rate = 0;
1100 }
1101
1102 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1103 {
1104 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1105 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1106 config->bind_address ? config->bind_address : my_address, buf, len);
1107 }
1108 return;
1109 }
1110 t = session[s].tunnel;
1111 sp = &session[s];
1112
1113 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1114 if (config->max_packets > 0)
1115 {
1116 if (sess_local[s].last_packet_out == TIME)
1117 {
1118 int max = config->max_packets;
1119
1120 // All packets for throttled sessions are handled by the
1121 // master, so further limit by using the throttle rate.
1122 // A bit of a kludge, since throttle rate is in kbps,
1123 // but should still be generous given our average DSL
1124 // packet size is 200 bytes: a limit of 28kbps equates
1125 // to around 180 packets per second.
1126 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1127 max = sp->throttle_out;
1128
1129 if (++sess_local[s].packets_out > max)
1130 {
1131 sess_local[s].packets_dropped++;
1132 return;
1133 }
1134 }
1135 else
1136 {
1137 if (sess_local[s].packets_dropped)
1138 {
1139 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1140 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1141 sess_local[s].packets_dropped, sess_local[s].packets_out,
1142 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1143 sp->user);
1144 }
1145
1146 sess_local[s].last_packet_out = TIME;
1147 sess_local[s].packets_out = 1;
1148 sess_local[s].packets_dropped = 0;
1149 }
1150 }
1151
1152 // run access-list if any
1153 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1154 return;
1155
1156 // adjust MSS on SYN and SYN,ACK packets with options
1157 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1158 {
1159 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1160 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1161 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1162 }
1163
1164 if (sp->tbf_out)
1165 {
1166 // Are we throttling this session?
1167 if (config->cluster_iam_master)
1168 tbf_queue_packet(sp->tbf_out, data, size);
1169 else
1170 master_throttle_packet(sp->tbf_out, data, size);
1171 return;
1172 }
1173
1174 if (sp->walled_garden && !config->cluster_iam_master)
1175 {
1176 // We are walled-gardening this
1177 master_garden_packet(s, data, size);
1178 return;
1179 }
1180
1181 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1182
1183 // Add on L2TP header
1184 {
1185 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1186 if (!p) return;
1187 tunnelsend(b, len + (p-b), t); // send it...
1188 }
1189
1190 // Snooping this session, send it to intercept box
1191 if (sp->snoop_ip && sp->snoop_port)
1192 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1193
1194 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1195 sp->cout_delta += len;
1196 sp->pout++;
1197 udp_tx += len;
1198
1199 sess_local[s].cout += len; // To send to master..
1200 sess_local[s].pout++;
1201 }
1202
1203 // process outgoing (to tunnel) IPv6
1204 //
1205 static void processipv6out(uint8_t * buf, int len)
1206 {
1207 sessionidt s;
1208 sessiont *sp;
1209 tunnelidt t;
1210 in_addr_t ip;
1211 struct in6_addr ip6;
1212
1213 uint8_t *data = buf; // Keep a copy of the originals.
1214 int size = len;
1215
1216 uint8_t b[MAXETHER + 20];
1217
1218 CSTAT(processipv6out);
1219
1220 if (len < MIN_IP_SIZE)
1221 {
1222 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1223 STAT(tunnel_tx_errors);
1224 return;
1225 }
1226 if (len >= MAXETHER)
1227 {
1228 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1229 STAT(tunnel_tx_errors);
1230 return;
1231 }
1232
1233 // Skip the tun header
1234 buf += 4;
1235 len -= 4;
1236
1237 // Got an IP header now
1238 if (*(uint8_t *)(buf) >> 4 != 6)
1239 {
1240 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1241 return;
1242 }
1243
1244 ip6 = *(struct in6_addr *)(buf+24);
1245 s = sessionbyipv6(ip6);
1246
1247 if (s == 0)
1248 {
1249 ip = *(uint32_t *)(buf + 32);
1250 s = sessionbyip(ip);
1251 }
1252
1253 if (s == 0)
1254 {
1255 // Is this a packet for a session that doesn't exist?
1256 static int rate = 0; // Number of ICMP packets we've sent this second.
1257 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1258
1259 if (last != time_now)
1260 {
1261 last = time_now;
1262 rate = 0;
1263 }
1264
1265 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1266 {
1267 // FIXME: Should send icmp6 host unreachable
1268 }
1269 return;
1270 }
1271 t = session[s].tunnel;
1272 sp = &session[s];
1273
1274 // FIXME: add DoS prevention/filters?
1275
1276 if (sp->tbf_out)
1277 {
1278 // Are we throttling this session?
1279 if (config->cluster_iam_master)
1280 tbf_queue_packet(sp->tbf_out, data, size);
1281 else
1282 master_throttle_packet(sp->tbf_out, data, size);
1283 return;
1284 }
1285 else if (sp->walled_garden && !config->cluster_iam_master)
1286 {
1287 // We are walled-gardening this
1288 master_garden_packet(s, data, size);
1289 return;
1290 }
1291
1292 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1293
1294 // Add on L2TP header
1295 {
1296 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1297 if (!p) return;
1298 tunnelsend(b, len + (p-b), t); // send it...
1299 }
1300
1301 // Snooping this session, send it to intercept box
1302 if (sp->snoop_ip && sp->snoop_port)
1303 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1304
1305 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1306 sp->cout_delta += len;
1307 sp->pout++;
1308 udp_tx += len;
1309
1310 sess_local[s].cout += len; // To send to master..
1311 sess_local[s].pout++;
1312 }
1313
1314 //
1315 // Helper routine for the TBF filters.
1316 // Used to send queued data in to the user!
1317 //
1318 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1319 {
1320 sessiont *sp;
1321 tunnelidt t;
1322 in_addr_t ip;
1323
1324 uint8_t b[MAXETHER + 20];
1325
1326 if (len < 0 || len > MAXETHER)
1327 {
1328 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1329 return;
1330 }
1331
1332 // Skip the tun header
1333 buf += 4;
1334 len -= 4;
1335
1336 ip = *(in_addr_t *)(buf + 16);
1337
1338 if (!session[s].ip)
1339 return;
1340
1341 t = session[s].tunnel;
1342 sp = &session[s];
1343
1344 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1345
1346 // Add on L2TP header
1347 {
1348 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1349 if (!p) return;
1350 tunnelsend(b, len + (p-b), t); // send it...
1351 }
1352
1353 // Snooping this session.
1354 if (sp->snoop_ip && sp->snoop_port)
1355 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1356
1357 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1358 sp->cout_delta += len;
1359 sp->pout++;
1360 udp_tx += len;
1361
1362 sess_local[s].cout += len; // To send to master..
1363 sess_local[s].pout++;
1364 }
1365
1366 // add an AVP (16 bit)
1367 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1368 {
1369 uint16_t l = (m ? 0x8008 : 0x0008);
1370 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1371 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1372 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1373 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1374 c->length += 8;
1375 }
1376
1377 // add an AVP (32 bit)
1378 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1379 {
1380 uint16_t l = (m ? 0x800A : 0x000A);
1381 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1382 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1383 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1384 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1385 c->length += 10;
1386 }
1387
1388 // add an AVP (string)
1389 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1390 {
1391 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1392 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1393 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1394 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1395 memcpy(c->buf + c->length + 6, val, strlen(val));
1396 c->length += 6 + strlen(val);
1397 }
1398
1399 // add a binary AVP
1400 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1401 {
1402 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1403 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1404 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1405 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1406 memcpy(c->buf + c->length + 6, val, len);
1407 c->length += 6 + len;
1408 }
1409
1410 // new control connection
1411 static controlt *controlnew(uint16_t mtype)
1412 {
1413 controlt *c;
1414 if (!controlfree)
1415 c = malloc(sizeof(controlt));
1416 else
1417 {
1418 c = controlfree;
1419 controlfree = c->next;
1420 }
1421 assert(c);
1422 c->next = 0;
1423 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1424 c->length = 12;
1425 control16(c, 0, mtype, 1);
1426 return c;
1427 }
1428
1429 // send zero block if nothing is waiting
1430 // (ZLB send).
1431 static void controlnull(tunnelidt t)
1432 {
1433 uint8_t buf[12];
1434 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1435 return;
1436
1437 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1438 *(uint16_t *) (buf + 2) = htons(12); // length
1439 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1440 *(uint16_t *) (buf + 6) = htons(0); // session
1441 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1442 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1443 tunnelsend(buf, 12, t);
1444 }
1445
1446 // add a control message to a tunnel, and send if within window
1447 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1448 {
1449 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1450 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1451 *(uint16_t *) (c->buf + 6) = htons(far); // session
1452 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1453 tunnel[t].ns++; // advance sequence
1454 // link in message in to queue
1455 if (tunnel[t].controlc)
1456 tunnel[t].controle->next = c;
1457 else
1458 tunnel[t].controls = c;
1459
1460 tunnel[t].controle = c;
1461 tunnel[t].controlc++;
1462
1463 // send now if space in window
1464 if (tunnel[t].controlc <= tunnel[t].window)
1465 {
1466 tunnel[t].try = 0; // first send
1467 tunnelsend(c->buf, c->length, t);
1468 }
1469 }
1470
1471 //
1472 // Throttle or Unthrottle a session
1473 //
1474 // Throttle the data from/to through a session to no more than
1475 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1476 // user).
1477 //
1478 // If either value is -1, the current value is retained for that
1479 // direction.
1480 //
1481 void throttle_session(sessionidt s, int rate_in, int rate_out)
1482 {
1483 if (!session[s].opened)
1484 return; // No-one home.
1485
1486 if (!*session[s].user)
1487 return; // User not logged in
1488
1489 if (rate_in >= 0)
1490 {
1491 int bytes = rate_in * 1024 / 8; // kbits to bytes
1492 if (session[s].tbf_in)
1493 free_tbf(session[s].tbf_in);
1494
1495 if (rate_in > 0)
1496 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1497 else
1498 session[s].tbf_in = 0;
1499
1500 session[s].throttle_in = rate_in;
1501 }
1502
1503 if (rate_out >= 0)
1504 {
1505 int bytes = rate_out * 1024 / 8;
1506 if (session[s].tbf_out)
1507 free_tbf(session[s].tbf_out);
1508
1509 if (rate_out > 0)
1510 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1511 else
1512 session[s].tbf_out = 0;
1513
1514 session[s].throttle_out = rate_out;
1515 }
1516 }
1517
1518 // add/remove filters from session (-1 = no change)
1519 void filter_session(sessionidt s, int filter_in, int filter_out)
1520 {
1521 if (!session[s].opened)
1522 return; // No-one home.
1523
1524 if (!*session[s].user)
1525 return; // User not logged in
1526
1527 // paranoia
1528 if (filter_in > MAXFILTER) filter_in = -1;
1529 if (filter_out > MAXFILTER) filter_out = -1;
1530 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1531 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1532
1533 if (filter_in >= 0)
1534 {
1535 if (session[s].filter_in)
1536 ip_filters[session[s].filter_in - 1].used--;
1537
1538 if (filter_in > 0)
1539 ip_filters[filter_in - 1].used++;
1540
1541 session[s].filter_in = filter_in;
1542 }
1543
1544 if (filter_out >= 0)
1545 {
1546 if (session[s].filter_out)
1547 ip_filters[session[s].filter_out - 1].used--;
1548
1549 if (filter_out > 0)
1550 ip_filters[filter_out - 1].used++;
1551
1552 session[s].filter_out = filter_out;
1553 }
1554 }
1555
1556 // start tidy shutdown of session
1557 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1558 {
1559 int walled_garden = session[s].walled_garden;
1560
1561
1562 CSTAT(sessionshutdown);
1563
1564 if (!session[s].opened)
1565 {
1566 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1567 return; // not a live session
1568 }
1569
1570 if (!session[s].die)
1571 {
1572 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1573 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1574 run_plugins(PLUGIN_KILL_SESSION, &data);
1575 }
1576
1577 if (session[s].ip && !walled_garden && !session[s].die)
1578 {
1579 // RADIUS Stop message
1580 uint16_t r = radiusnew(s);
1581 if (r)
1582 {
1583 // stop, if not already trying
1584 if (radius[r].state != RADIUSSTOP)
1585 radiussend(r, RADIUSSTOP);
1586 }
1587 else
1588 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1589
1590 // Save counters to dump to accounting file
1591 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1592 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1593 }
1594
1595 if (session[s].ip)
1596 { // IP allocated, clear and unroute
1597 int r;
1598 int routed = 0;
1599 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1600 {
1601 if ((session[s].ip & session[s].route[r].mask) ==
1602 (session[s].route[r].ip & session[s].route[r].mask))
1603 routed++;
1604
1605 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1606 session[s].route[r].ip = 0;
1607 }
1608
1609 if (session[s].ip_pool_index == -1) // static ip
1610 {
1611 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1612 session[s].ip = 0;
1613 }
1614 else
1615 free_ip_address(s);
1616
1617 // unroute IPv6, if setup
1618 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1619 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1620 }
1621
1622 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1623 throttle_session(s, 0, 0);
1624
1625 if (result)
1626 { // Send CDN
1627 controlt *c = controlnew(14); // sending CDN
1628 if (error)
1629 {
1630 uint8_t buf[4];
1631 *(uint16_t *) buf = htons(result);
1632 *(uint16_t *) (buf+2) = htons(error);
1633 controlb(c, 1, buf, 4, 1);
1634 }
1635 else
1636 control16(c, 1, result, 1);
1637
1638 control16(c, 14, s, 1); // assigned session (our end)
1639 controladd(c, session[s].far, session[s].tunnel); // send the message
1640 }
1641
1642 if (!session[s].die)
1643 session[s].die = TIME + 150; // Clean up in 15 seconds
1644
1645 // update filter refcounts
1646 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1647 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1648
1649 // clear PPP state
1650 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1651 sess_local[s].lcp.restart = 0;
1652 sess_local[s].ipcp.restart = 0;
1653 sess_local[s].ipv6cp.restart = 0;
1654 sess_local[s].ccp.restart = 0;
1655
1656 cluster_send_session(s);
1657 }
1658
1659 void sendipcp(sessionidt s, tunnelidt t)
1660 {
1661 uint8_t buf[MAXETHER];
1662 uint8_t *q;
1663
1664 CSTAT(sendipcp);
1665 LOG(3, s, t, "IPCP: send ConfigReq\n");
1666
1667 if (!session[s].unique_id)
1668 {
1669 if (!++last_id) ++last_id; // skip zero
1670 session[s].unique_id = last_id;
1671 }
1672
1673 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP);
1674 if (!q) return;
1675
1676 *q = ConfigReq;
1677 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1678 *(uint16_t *) (q + 2) = htons(10); // packet length
1679 q[4] = 3; // ip address option
1680 q[5] = 6; // option length
1681 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1682 config->bind_address ? config->bind_address :
1683 my_address; // send my IP
1684
1685 tunnelsend(buf, 10 + (q - buf), t); // send it
1686 restart_timer(s, ipcp);
1687 }
1688
1689 void sendipv6cp(sessionidt s, tunnelidt t)
1690 {
1691 uint8_t buf[MAXETHER];
1692 uint8_t *q;
1693
1694 CSTAT(sendipv6cp);
1695 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1696
1697 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1698 if (!q) return;
1699
1700 *q = ConfigReq;
1701 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1702 // only send one type
1703 // of request
1704 *(uint16_t *) (q + 2) = htons(14);
1705 q[4] = 1; // interface identifier option
1706 q[5] = 10; // option length
1707 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1708 *(uint32_t *) (q + 10) = 0;
1709 q[13] = 1;
1710
1711 tunnelsend(buf, 14 + (q - buf), t); // send it
1712 restart_timer(s, ipv6cp);
1713 }
1714
1715 static void sessionclear(sessionidt s)
1716 {
1717 memset(&session[s], 0, sizeof(session[s]));
1718 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1719 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1720
1721 session[s].tunnel = T_FREE; // Mark it as free.
1722 session[s].next = sessionfree;
1723 sessionfree = s;
1724 }
1725
1726 // kill a session now
1727 void sessionkill(sessionidt s, char *reason)
1728 {
1729
1730 CSTAT(sessionkill);
1731
1732 if (!session[s].opened) // not alive
1733 return;
1734
1735 if (session[s].next)
1736 {
1737 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1738 return;
1739 }
1740
1741 session[s].die = TIME;
1742 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1743 if (sess_local[s].radius)
1744 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1745
1746 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1747 sessionclear(s);
1748 cluster_send_session(s);
1749 }
1750
1751 static void tunnelclear(tunnelidt t)
1752 {
1753 if (!t) return;
1754 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1755 tunnel[t].state = TUNNELFREE;
1756 }
1757
1758 // kill a tunnel now
1759 static void tunnelkill(tunnelidt t, char *reason)
1760 {
1761 sessionidt s;
1762 controlt *c;
1763
1764 CSTAT(tunnelkill);
1765
1766 tunnel[t].state = TUNNELDIE;
1767
1768 // free control messages
1769 while ((c = tunnel[t].controls))
1770 {
1771 controlt * n = c->next;
1772 tunnel[t].controls = n;
1773 tunnel[t].controlc--;
1774 c->next = controlfree;
1775 controlfree = c;
1776 }
1777 // kill sessions
1778 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1779 if (session[s].tunnel == t)
1780 sessionkill(s, reason);
1781
1782 // free tunnel
1783 tunnelclear(t);
1784 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1785 cli_tunnel_actions[t].action = 0;
1786 cluster_send_tunnel(t);
1787 }
1788
1789 // shut down a tunnel cleanly
1790 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1791 {
1792 sessionidt s;
1793
1794 CSTAT(tunnelshutdown);
1795
1796 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1797 {
1798 // never set up, can immediately kill
1799 tunnelkill(t, reason);
1800 return;
1801 }
1802 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1803
1804 // close session
1805 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1806 if (session[s].tunnel == t)
1807 sessionshutdown(s, reason, 0, 0);
1808
1809 tunnel[t].state = TUNNELDIE;
1810 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1811 cluster_send_tunnel(t);
1812 // TBA - should we wait for sessions to stop?
1813 if (result)
1814 {
1815 controlt *c = controlnew(4); // sending StopCCN
1816 if (error)
1817 {
1818 uint8_t buf[64];
1819 int l = 4;
1820 *(uint16_t *) buf = htons(result);
1821 *(uint16_t *) (buf+2) = htons(error);
1822 if (msg)
1823 {
1824 int m = strlen(msg);
1825 if (m + 4 > sizeof(buf))
1826 m = sizeof(buf) - 4;
1827
1828 memcpy(buf+4, msg, m);
1829 l += m;
1830 }
1831
1832 controlb(c, 1, buf, l, 1);
1833 }
1834 else
1835 control16(c, 1, result, 1);
1836
1837 control16(c, 9, t, 1); // assigned tunnel (our end)
1838 controladd(c, 0, t); // send the message
1839 }
1840 }
1841
1842 // read and process packet on tunnel (UDP)
1843 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1844 {
1845 uint8_t *chapresponse = NULL;
1846 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1847 uint8_t *p = buf + 2;
1848
1849
1850 CSTAT(processudp);
1851
1852 udp_rx += len;
1853 udp_rx_pkt++;
1854 LOG_HEX(5, "UDP Data", buf, len);
1855 STAT(tunnel_rx_packets);
1856 INC_STAT(tunnel_rx_bytes, len);
1857 if (len < 6)
1858 {
1859 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1860 STAT(tunnel_rx_errors);
1861 return;
1862 }
1863 if ((buf[1] & 0x0F) != 2)
1864 {
1865 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1866 STAT(tunnel_rx_errors);
1867 return;
1868 }
1869 if (*buf & 0x40)
1870 { // length
1871 l = ntohs(*(uint16_t *) p);
1872 p += 2;
1873 }
1874 t = ntohs(*(uint16_t *) p);
1875 p += 2;
1876 s = ntohs(*(uint16_t *) p);
1877 p += 2;
1878 if (s >= MAXSESSION)
1879 {
1880 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1881 STAT(tunnel_rx_errors);
1882 return;
1883 }
1884 if (t >= MAXTUNNEL)
1885 {
1886 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1887 STAT(tunnel_rx_errors);
1888 return;
1889 }
1890 if (*buf & 0x08)
1891 { // ns/nr
1892 ns = ntohs(*(uint16_t *) p);
1893 p += 2;
1894 nr = ntohs(*(uint16_t *) p);
1895 p += 2;
1896 }
1897 if (*buf & 0x02)
1898 { // offset
1899 uint16_t o = ntohs(*(uint16_t *) p);
1900 p += o + 2;
1901 }
1902 if ((p - buf) > l)
1903 {
1904 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1905 STAT(tunnel_rx_errors);
1906 return;
1907 }
1908 l -= (p - buf);
1909
1910 // used to time out old tunnels
1911 if (t && tunnel[t].state == TUNNELOPEN)
1912 tunnel[t].lastrec = time_now;
1913
1914 if (*buf & 0x80)
1915 { // control
1916 uint16_t message = 0xFFFF; // message type
1917 uint8_t fatal = 0;
1918 uint8_t mandatory = 0;
1919 uint16_t asession = 0; // assigned session
1920 uint32_t amagic = 0; // magic number
1921 uint8_t aflags = 0; // flags from last LCF
1922 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1923 char called[MAXTEL] = ""; // called number
1924 char calling[MAXTEL] = ""; // calling number
1925
1926 if (!config->cluster_iam_master)
1927 {
1928 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1929 return;
1930 }
1931
1932 // control messages must have bits 0x80|0x40|0x08
1933 // (type, length and sequence) set, and bits 0x02|0x01
1934 // (offset and priority) clear
1935 if ((*buf & 0xCB) != 0xC8)
1936 {
1937 LOG(1, s, t, "Bad control header %02X\n", *buf);
1938 STAT(tunnel_rx_errors);
1939 return;
1940 }
1941
1942 // check for duplicate tunnel open message
1943 if (!t && ns == 0)
1944 {
1945 int i;
1946
1947 //
1948 // Is this a duplicate of the first packet? (SCCRQ)
1949 //
1950 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1951 {
1952 if (tunnel[i].state != TUNNELOPENING ||
1953 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1954 tunnel[i].port != ntohs(addr->sin_port) )
1955 continue;
1956 t = i;
1957 LOG(3, s, t, "Duplicate SCCRQ?\n");
1958 break;
1959 }
1960 }
1961
1962 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1963 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1964
1965 // if no tunnel specified, assign one
1966 if (!t)
1967 {
1968 if (!(t = new_tunnel()))
1969 {
1970 LOG(1, 0, 0, "No more tunnels\n");
1971 STAT(tunnel_overflow);
1972 return;
1973 }
1974 tunnelclear(t);
1975 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1976 tunnel[t].port = ntohs(addr->sin_port);
1977 tunnel[t].window = 4; // default window
1978 STAT(tunnel_created);
1979 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1980 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1981 }
1982
1983 // If the 'ns' just received is not the 'nr' we're
1984 // expecting, just send an ack and drop it.
1985 //
1986 // if 'ns' is less, then we got a retransmitted packet.
1987 // if 'ns' is greater than missed a packet. Either way
1988 // we should ignore it.
1989 if (ns != tunnel[t].nr)
1990 {
1991 // is this the sequence we were expecting?
1992 STAT(tunnel_rx_errors);
1993 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1994 t, ns, tunnel[t].nr);
1995
1996 if (l) // Is this not a ZLB?
1997 controlnull(t);
1998 return;
1999 }
2000
2001 // check sequence of this message
2002 {
2003 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2004 // some to clear maybe?
2005 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2006 {
2007 controlt *c = tunnel[t].controls;
2008 tunnel[t].controls = c->next;
2009 tunnel[t].controlc--;
2010 c->next = controlfree;
2011 controlfree = c;
2012 skip--;
2013 tunnel[t].try = 0; // we have progress
2014 }
2015
2016 // receiver advance (do here so quoted correctly in any sends below)
2017 if (l) tunnel[t].nr = (ns + 1);
2018 if (skip < 0) skip = 0;
2019 if (skip < tunnel[t].controlc)
2020 {
2021 // some control packets can now be sent that were previous stuck out of window
2022 int tosend = tunnel[t].window - skip;
2023 controlt *c = tunnel[t].controls;
2024 while (c && skip)
2025 {
2026 c = c->next;
2027 skip--;
2028 }
2029 while (c && tosend)
2030 {
2031 tunnel[t].try = 0; // first send
2032 tunnelsend(c->buf, c->length, t);
2033 c = c->next;
2034 tosend--;
2035 }
2036 }
2037 if (!tunnel[t].controlc)
2038 tunnel[t].retry = 0; // caught up
2039 }
2040 if (l)
2041 { // if not a null message
2042 int result = 0;
2043 int error = 0;
2044 char *msg = 0;
2045
2046 // process AVPs
2047 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2048 {
2049 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2050 uint8_t *b = p;
2051 uint8_t flags = *p;
2052 uint16_t mtype;
2053 if (n > l)
2054 {
2055 LOG(1, s, t, "Invalid length in AVP\n");
2056 STAT(tunnel_rx_errors);
2057 return;
2058 }
2059 p += n; // next
2060 l -= n;
2061 if (flags & 0x3C) // reserved bits, should be clear
2062 {
2063 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2064 fatal = flags;
2065 result = 2; // general error
2066 error = 3; // reserved field non-zero
2067 msg = 0;
2068 continue; // next
2069 }
2070 b += 2;
2071 if (*(uint16_t *) (b))
2072 {
2073 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
2074 fatal = flags;
2075 result = 2; // general error
2076 error = 6; // generic vendor-specific error
2077 msg = "unsupported vendor-specific";
2078 continue; // next
2079 }
2080 b += 2;
2081 mtype = ntohs(*(uint16_t *) (b));
2082 b += 2;
2083 n -= 6;
2084
2085 if (flags & 0x40)
2086 {
2087 uint16_t orig_len;
2088
2089 // handle hidden AVPs
2090 if (!*config->l2tp_secret)
2091 {
2092 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2093 fatal = flags;
2094 result = 2; // general error
2095 error = 6; // generic vendor-specific error
2096 msg = "secret not specified";
2097 continue;
2098 }
2099 if (!session[s].random_vector_length)
2100 {
2101 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2102 fatal = flags;
2103 result = 2; // general error
2104 error = 6; // generic
2105 msg = "no random vector";
2106 continue;
2107 }
2108 if (n < 8)
2109 {
2110 LOG(2, s, t, "Short hidden AVP.\n");
2111 fatal = flags;
2112 result = 2; // general error
2113 error = 2; // length is wrong
2114 msg = 0;
2115 continue;
2116 }
2117
2118 // Unhide the AVP
2119 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2120
2121 orig_len = ntohs(*(uint16_t *) b);
2122 if (orig_len > n + 2)
2123 {
2124 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2125 orig_len, n);
2126
2127 fatal = flags;
2128 result = 2; // general error
2129 error = 2; // length is wrong
2130 msg = 0;
2131 continue;
2132 }
2133
2134 b += 2;
2135 n = orig_len;
2136 }
2137
2138 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2139 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2140
2141 switch (mtype)
2142 {
2143 case 0: // message type
2144 message = ntohs(*(uint16_t *) b);
2145 mandatory = flags & 0x80;
2146 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2147 break;
2148 case 1: // result code
2149 {
2150 uint16_t rescode = ntohs(*(uint16_t *) b);
2151 const char* resdesc = "(unknown)";
2152 if (message == 4)
2153 { /* StopCCN */
2154 resdesc = l2tp_stopccn_result_code(rescode);
2155 }
2156 else if (message == 14)
2157 { /* CDN */
2158 resdesc = l2tp_cdn_result_code(rescode);
2159 }
2160
2161 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2162 if (n >= 4)
2163 {
2164 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2165 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2166 }
2167 if (n > 4)
2168 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2169
2170 break;
2171 }
2172 break;
2173 case 2: // protocol version
2174 {
2175 version = ntohs(*(uint16_t *) (b));
2176 LOG(4, s, t, " Protocol version = %d\n", version);
2177 if (version && version != 0x0100)
2178 { // allow 0.0 and 1.0
2179 LOG(1, s, t, " Bad protocol version %04X\n", version);
2180 fatal = flags;
2181 result = 5; // unspported protocol version
2182 error = 0x0100; // supported version
2183 msg = 0;
2184 continue; // next
2185 }
2186 }
2187 break;
2188 case 3: // framing capabilities
2189 // LOG(4, s, t, "Framing capabilities\n");
2190 break;
2191 case 4: // bearer capabilities
2192 // LOG(4, s, t, "Bearer capabilities\n");
2193 break;
2194 case 5: // tie breaker
2195 // We never open tunnels, so we don't care about tie breakers
2196 // LOG(4, s, t, "Tie breaker\n");
2197 continue;
2198 case 6: // firmware revision
2199 // LOG(4, s, t, "Firmware revision\n");
2200 break;
2201 case 7: // host name
2202 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2203 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2204 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2205 // TBA - to send to RADIUS
2206 break;
2207 case 8: // vendor name
2208 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2209 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2210 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2211 break;
2212 case 9: // assigned tunnel
2213 tunnel[t].far = ntohs(*(uint16_t *) (b));
2214 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2215 break;
2216 case 10: // rx window
2217 tunnel[t].window = ntohs(*(uint16_t *) (b));
2218 if (!tunnel[t].window)
2219 tunnel[t].window = 1; // window of 0 is silly
2220 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2221 break;
2222 case 11: // Challenge
2223 {
2224 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2225 build_chap_response(b, 2, n, &chapresponse);
2226 }
2227 break;
2228 case 13: // Response
2229 // Why did they send a response? We never challenge.
2230 LOG(2, s, t, " received unexpected challenge response\n");
2231 break;
2232
2233 case 14: // assigned session
2234 asession = session[s].far = ntohs(*(uint16_t *) (b));
2235 LOG(4, s, t, " assigned session = %d\n", asession);
2236 break;
2237 case 15: // call serial number
2238 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2239 break;
2240 case 18: // bearer type
2241 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2242 // TBA - for RADIUS
2243 break;
2244 case 19: // framing type
2245 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2246 // TBA
2247 break;
2248 case 21: // called number
2249 memset(called, 0, sizeof(called));
2250 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2251 LOG(4, s, t, " Called <%s>\n", called);
2252 break;
2253 case 22: // calling number
2254 memset(calling, 0, sizeof(calling));
2255 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2256 LOG(4, s, t, " Calling <%s>\n", calling);
2257 break;
2258 case 23: // subtype
2259 break;
2260 case 24: // tx connect speed
2261 if (n == 4)
2262 {
2263 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2264 }
2265 else
2266 {
2267 // AS5300s send connect speed as a string
2268 char tmp[30];
2269 memset(tmp, 0, sizeof(tmp));
2270 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2271 session[s].tx_connect_speed = atol(tmp);
2272 }
2273 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2274 break;
2275 case 38: // rx connect speed
2276 if (n == 4)
2277 {
2278 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2279 }
2280 else
2281 {
2282 // AS5300s send connect speed as a string
2283 char tmp[30];
2284 memset(tmp, 0, sizeof(tmp));
2285 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2286 session[s].rx_connect_speed = atol(tmp);
2287 }
2288 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2289 break;
2290 case 25: // Physical Channel ID
2291 {
2292 uint32_t tmp = ntohl(*(uint32_t *) b);
2293 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2294 break;
2295 }
2296 case 29: // Proxy Authentication Type
2297 {
2298 uint16_t atype = ntohs(*(uint16_t *)b);
2299 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2300 break;
2301 }
2302 case 30: // Proxy Authentication Name
2303 {
2304 char authname[64];
2305 memset(authname, 0, sizeof(authname));
2306 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2307 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2308 authname);
2309 break;
2310 }
2311 case 31: // Proxy Authentication Challenge
2312 {
2313 LOG(4, s, t, " Proxy Auth Challenge\n");
2314 break;
2315 }
2316 case 32: // Proxy Authentication ID
2317 {
2318 uint16_t authid = ntohs(*(uint16_t *)(b));
2319 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2320 break;
2321 }
2322 case 33: // Proxy Authentication Response
2323 LOG(4, s, t, " Proxy Auth Response\n");
2324 break;
2325 case 27: // last sent lcp
2326 { // find magic number
2327 uint8_t *p = b, *e = p + n;
2328 while (p + 1 < e && p[1] && p + p[1] <= e)
2329 {
2330 if (*p == 5 && p[1] == 6) // Magic-Number
2331 amagic = ntohl(*(uint32_t *) (p + 2));
2332 else if (*p == 7) // Protocol-Field-Compression
2333 aflags |= SESSION_PFC;
2334 else if (*p == 8) // Address-and-Control-Field-Compression
2335 aflags |= SESSION_ACFC;
2336 p += p[1];
2337 }
2338 }
2339 break;
2340 case 28: // last recv lcp confreq
2341 break;
2342 case 26: // Initial Received LCP CONFREQ
2343 break;
2344 case 39: // seq required - we control it as an LNS anyway...
2345 break;
2346 case 36: // Random Vector
2347 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2348 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2349 if (n > sizeof(session[s].random_vector))
2350 n = sizeof(session[s].random_vector);
2351 memcpy(session[s].random_vector, b, n);
2352 session[s].random_vector_length = n;
2353 break;
2354 default:
2355 {
2356 static char e[] = "unknown AVP 0xXXXX";
2357 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2358 fatal = flags;
2359 result = 2; // general error
2360 error = 8; // unknown mandatory AVP
2361 sprintf((msg = e) + 14, "%04x", mtype);
2362 continue; // next
2363 }
2364 }
2365 }
2366 // process message
2367 if (fatal & 0x80)
2368 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2369 else
2370 switch (message)
2371 {
2372 case 1: // SCCRQ - Start Control Connection Request
2373 tunnel[t].state = TUNNELOPENING;
2374 if (main_quit != QUIT_SHUTDOWN)
2375 {
2376 controlt *c = controlnew(2); // sending SCCRP
2377 control16(c, 2, version, 1); // protocol version
2378 control32(c, 3, 3, 1); // framing
2379 controls(c, 7, hostname, 1); // host name
2380 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2381 control16(c, 9, t, 1); // assigned tunnel
2382 controladd(c, 0, t); // send the resply
2383 }
2384 else
2385 {
2386 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2387 }
2388 break;
2389 case 2: // SCCRP
2390 tunnel[t].state = TUNNELOPEN;
2391 break;
2392 case 3: // SCCN
2393 tunnel[t].state = TUNNELOPEN;
2394 controlnull(t); // ack
2395 break;
2396 case 4: // StopCCN
2397 controlnull(t); // ack
2398 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2399 break;
2400 case 6: // HELLO
2401 controlnull(t); // simply ACK
2402 break;
2403 case 7: // OCRQ
2404 // TBA
2405 break;
2406 case 8: // OCRO
2407 // TBA
2408 break;
2409 case 9: // OCCN
2410 // TBA
2411 break;
2412 case 10: // ICRQ
2413 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2414 {
2415 controlt *c = controlnew(11); // ICRP
2416
2417 s = sessionfree;
2418 sessionfree = session[s].next;
2419 memset(&session[s], 0, sizeof(session[s]));
2420
2421 if (s > config->cluster_highest_sessionid)
2422 config->cluster_highest_sessionid = s;
2423
2424 session[s].opened = time_now;
2425 session[s].tunnel = t;
2426 session[s].far = asession;
2427 session[s].last_packet = time_now;
2428 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2429 control16(c, 14, s, 1); // assigned session
2430 controladd(c, asession, t); // send the reply
2431
2432 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2433 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2434
2435 session[s].ppp.phase = Establish;
2436 session[s].ppp.lcp = Starting;
2437
2438 STAT(session_created);
2439 break;
2440 }
2441
2442 {
2443 controlt *c = controlnew(14); // CDN
2444 if (!sessionfree)
2445 {
2446 STAT(session_overflow);
2447 LOG(1, 0, t, "No free sessions\n");
2448 control16(c, 1, 4, 0); // temporary lack of resources
2449 }
2450 else
2451 control16(c, 1, 2, 7); // shutting down, try another
2452
2453 controladd(c, asession, t); // send the message
2454 }
2455 return;
2456 case 11: // ICRP
2457 // TBA
2458 break;
2459 case 12: // ICCN
2460 if (amagic == 0) amagic = time_now;
2461 session[s].magic = amagic; // set magic number
2462 session[s].flags = aflags; // set flags received
2463 session[s].mru = PPPMTU; // default
2464 controlnull(t); // ack
2465
2466 // start LCP
2467 sess_local[s].lcp_authtype = config->radius_authprefer;
2468 sess_local[s].ppp_mru = MRU;
2469 sendlcp(s, t);
2470 change_state(s, lcp, RequestSent);
2471 break;
2472
2473 case 14: // CDN
2474 controlnull(t); // ack
2475 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2476 break;
2477 case 0xFFFF:
2478 LOG(1, s, t, "Missing message type\n");
2479 break;
2480 default:
2481 STAT(tunnel_rx_errors);
2482 if (mandatory)
2483 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2484 else
2485 LOG(1, s, t, "Unknown message type %d\n", message);
2486 break;
2487 }
2488 if (chapresponse) free(chapresponse);
2489 cluster_send_tunnel(t);
2490 }
2491 else
2492 {
2493 LOG(4, s, t, " Got a ZLB ack\n");
2494 }
2495 }
2496 else
2497 { // data
2498 uint16_t proto;
2499
2500 LOG_HEX(5, "Receive Tunnel Data", p, l);
2501 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2502 { // HDLC address header, discard
2503 p += 2;
2504 l -= 2;
2505 }
2506 if (l < 2)
2507 {
2508 LOG(1, s, t, "Short ppp length %d\n", l);
2509 STAT(tunnel_rx_errors);
2510 return;
2511 }
2512 if (*p & 1)
2513 {
2514 proto = *p++;
2515 l--;
2516 }
2517 else
2518 {
2519 proto = ntohs(*(uint16_t *) p);
2520 p += 2;
2521 l -= 2;
2522 }
2523
2524 if (s && !session[s].opened) // Is something wrong??
2525 {
2526 if (!config->cluster_iam_master)
2527 {
2528 // Pass it off to the master to deal with..
2529 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2530 return;
2531 }
2532
2533
2534 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2535 STAT(tunnel_rx_errors);
2536 return;
2537 }
2538
2539 if (proto == PPPPAP)
2540 {
2541 session[s].last_packet = time_now;
2542 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2543 processpap(s, t, p, l);
2544 }
2545 else if (proto == PPPCHAP)
2546 {
2547 session[s].last_packet = time_now;
2548 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2549 processchap(s, t, p, l);
2550 }
2551 else if (proto == PPPLCP)
2552 {
2553 session[s].last_packet = time_now;
2554 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2555 processlcp(s, t, p, l);
2556 }
2557 else if (proto == PPPIPCP)
2558 {
2559 session[s].last_packet = time_now;
2560 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2561 processipcp(s, t, p, l);
2562 }
2563 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2564 {
2565 session[s].last_packet = time_now;
2566 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2567 processipv6cp(s, t, p, l);
2568 }
2569 else if (proto == PPPCCP)
2570 {
2571 session[s].last_packet = time_now;
2572 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2573 processccp(s, t, p, l);
2574 }
2575 else if (proto == PPPIP)
2576 {
2577 if (session[s].die)
2578 {
2579 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2580 return; // closing session, PPP not processed
2581 }
2582
2583 session[s].last_packet = time_now;
2584 if (session[s].walled_garden && !config->cluster_iam_master)
2585 {
2586 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2587 return;
2588 }
2589
2590 processipin(s, t, p, l);
2591 }
2592 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2593 {
2594 if (session[s].die)
2595 {
2596 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2597 return; // closing session, PPP not processed
2598 }
2599
2600 session[s].last_packet = time_now;
2601 if (session[s].walled_garden && !config->cluster_iam_master)
2602 {
2603 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2604 return;
2605 }
2606
2607 processipv6in(s, t, p, l);
2608 }
2609 else if (session[s].ppp.lcp == Opened)
2610 {
2611 uint8_t buf[MAXETHER];
2612 uint8_t *q;
2613 int mru = session[s].mru;
2614 if (mru > sizeof(buf)) mru = sizeof(buf);
2615
2616 l += 6;
2617 if (l > mru) l = mru;
2618
2619 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPLCP);
2620 if (!q) return;
2621
2622 *q = ProtocolRej;
2623 *(q + 1) = ++sess_local[s].lcp_ident;
2624 *(uint16_t *)(q + 2) = htons(l);
2625 *(uint16_t *)(q + 4) = htons(proto);
2626 memcpy(q + 6, p, l - 6);
2627
2628 if (proto == PPPIPV6CP)
2629 LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n");
2630 else
2631 LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto);
2632
2633 tunnelsend(buf, l + (q - buf), t);
2634 }
2635 else
2636 {
2637 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2638 proto, ppp_state(session[s].ppp.lcp));
2639 }
2640 }
2641 }
2642
2643 // read and process packet on tun
2644 static void processtun(uint8_t * buf, int len)
2645 {
2646 LOG_HEX(5, "Receive TUN Data", buf, len);
2647 STAT(tun_rx_packets);
2648 INC_STAT(tun_rx_bytes, len);
2649
2650 CSTAT(processtun);
2651
2652 eth_rx_pkt++;
2653 eth_rx += len;
2654 if (len < 22)
2655 {
2656 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2657 STAT(tun_rx_errors);
2658 return;
2659 }
2660
2661 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2662 processipout(buf, len);
2663 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2664 && config->ipv6_prefix.s6_addr[0])
2665 processipv6out(buf, len);
2666
2667 // Else discard.
2668 }
2669
2670 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2671 // that we look at the whole of the tunnel, radius and session tables
2672 // every second
2673 static void regular_cleanups(double period)
2674 {
2675 // Next tunnel, radius and session to check for actions on.
2676 static tunnelidt t = 0;
2677 static int r = 0;
2678 static sessionidt s = 0;
2679
2680 int t_actions = 0;
2681 int r_actions = 0;
2682 int s_actions = 0;
2683
2684 int t_slice;
2685 int r_slice;
2686 int s_slice;
2687
2688 int i;
2689 int a;
2690
2691 // divide up tables into slices based on the last run
2692 t_slice = config->cluster_highest_tunnelid * period;
2693 r_slice = (MAXRADIUS - 1) * period;
2694 s_slice = config->cluster_highest_sessionid * period;
2695
2696 if (t_slice < 1)
2697 t_slice = 1;
2698 else if (t_slice > config->cluster_highest_tunnelid)
2699 t_slice = config->cluster_highest_tunnelid;
2700
2701 if (r_slice < 1)
2702 r_slice = 1;
2703 else if (r_slice > (MAXRADIUS - 1))
2704 r_slice = MAXRADIUS - 1;
2705
2706 if (s_slice < 1)
2707 s_slice = 1;
2708 else if (s_slice > config->cluster_highest_sessionid)
2709 s_slice = config->cluster_highest_sessionid;
2710
2711 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2712
2713 for (i = 0; i < t_slice; i++)
2714 {
2715 t++;
2716 if (t > config->cluster_highest_tunnelid)
2717 t = 1;
2718
2719 // check for expired tunnels
2720 if (tunnel[t].die && tunnel[t].die <= TIME)
2721 {
2722 STAT(tunnel_timeout);
2723 tunnelkill(t, "Expired");
2724 t_actions++;
2725 continue;
2726 }
2727 // check for message resend
2728 if (tunnel[t].retry && tunnel[t].controlc)
2729 {
2730 // resend pending messages as timeout on reply
2731 if (tunnel[t].retry <= TIME)
2732 {
2733 controlt *c = tunnel[t].controls;
2734 uint8_t w = tunnel[t].window;
2735 tunnel[t].try++; // another try
2736 if (tunnel[t].try > 5)
2737 tunnelkill(t, "Timeout on control message"); // game over
2738 else
2739 while (c && w--)
2740 {
2741 tunnelsend(c->buf, c->length, t);
2742 c = c->next;
2743 }
2744
2745 t_actions++;
2746 }
2747 }
2748 // Send hello
2749 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
2750 {
2751 controlt *c = controlnew(6); // sending HELLO
2752 controladd(c, 0, t); // send the message
2753 LOG(3, 0, t, "Sending HELLO message\n");
2754 t_actions++;
2755 }
2756
2757 // Check for tunnel changes requested from the CLI
2758 if ((a = cli_tunnel_actions[t].action))
2759 {
2760 cli_tunnel_actions[t].action = 0;
2761 if (a & CLI_TUN_KILL)
2762 {
2763 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2764 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2765 t_actions++;
2766 }
2767 }
2768 }
2769
2770 for (i = 0; i < r_slice; i++)
2771 {
2772 r++;
2773 if (r >= MAXRADIUS)
2774 r = 1;
2775
2776 if (!radius[r].state)
2777 continue;
2778
2779 if (radius[r].retry <= TIME)
2780 {
2781 radiusretry(r);
2782 r_actions++;
2783 }
2784 }
2785
2786 for (i = 0; i < s_slice; i++)
2787 {
2788 s++;
2789 if (s > config->cluster_highest_sessionid)
2790 s = 1;
2791
2792 if (!session[s].opened) // Session isn't in use
2793 continue;
2794
2795 // check for expired sessions
2796 if (session[s].die)
2797 {
2798 if (session[s].die <= TIME)
2799 {
2800 sessionkill(s, "Expired");
2801 s_actions++;
2802 }
2803 continue;
2804 }
2805
2806 // PPP timeouts
2807 if (sess_local[s].lcp.restart <= time_now)
2808 {
2809 int next_state = session[s].ppp.lcp;
2810 switch (session[s].ppp.lcp)
2811 {
2812 case RequestSent:
2813 case AckReceived:
2814 next_state = RequestSent;
2815
2816 case AckSent:
2817 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2818 {
2819 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2820 sendlcp(s, session[s].tunnel);
2821 change_state(s, lcp, next_state);
2822 }
2823 else
2824 {
2825 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2826 STAT(session_timeout);
2827 }
2828
2829 s_actions++;
2830 }
2831
2832 if (session[s].die)
2833 continue;
2834 }
2835
2836 if (sess_local[s].ipcp.restart <= time_now)
2837 {
2838 int next_state = session[s].ppp.ipcp;
2839 switch (session[s].ppp.ipcp)
2840 {
2841 case RequestSent:
2842 case AckReceived:
2843 next_state = RequestSent;
2844
2845 case AckSent:
2846 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2847 {
2848 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2849 sendipcp(s, session[s].tunnel);
2850 change_state(s, ipcp, next_state);
2851 }
2852 else
2853 {
2854 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2855 STAT(session_timeout);
2856 }
2857
2858 s_actions++;
2859 }
2860
2861 if (session[s].die)
2862 continue;
2863 }
2864
2865 if (sess_local[s].ipv6cp.restart <= time_now)
2866 {
2867 int next_state = session[s].ppp.ipv6cp;
2868 switch (session[s].ppp.ipv6cp)
2869 {
2870 case RequestSent:
2871 case AckReceived:
2872 next_state = RequestSent;
2873
2874 case AckSent:
2875 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2876 {
2877 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2878 sendipv6cp(s, session[s].tunnel);
2879 change_state(s, ipv6cp, next_state);
2880 }
2881 else
2882 {
2883 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2884 change_state(s, ipv6cp, Stopped);
2885 }
2886
2887 s_actions++;
2888 }
2889 }
2890
2891 if (sess_local[s].ccp.restart <= time_now)
2892 {
2893 int next_state = session[s].ppp.ccp;
2894 switch (session[s].ppp.ccp)
2895 {
2896 case RequestSent:
2897 case AckReceived:
2898 next_state = RequestSent;
2899
2900 case AckSent:
2901 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2902 {
2903 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2904 sendccp(s, session[s].tunnel);
2905 change_state(s, ccp, next_state);
2906 }
2907 else
2908 {
2909 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2910 change_state(s, ccp, Stopped);
2911 }
2912
2913 s_actions++;
2914 }
2915 }
2916
2917 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2918 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2919 {
2920 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2921 STAT(session_timeout);
2922 s_actions++;
2923 continue;
2924 }
2925
2926 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2927 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
2928 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
2929 {
2930 uint8_t b[MAXETHER];
2931
2932 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2933 if (!q) continue;
2934
2935 *q = EchoReq;
2936 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2937 *(uint16_t *)(q + 2) = htons(8); // Length
2938 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2939
2940 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2941 (int)(time_now - session[s].last_packet));
2942 tunnelsend(b, 24, session[s].tunnel); // send it
2943 sess_local[s].last_echo = time_now;
2944 s_actions++;
2945 }
2946
2947 // Check for actions requested from the CLI
2948 if ((a = cli_session_actions[s].action))
2949 {
2950 int send = 0;
2951
2952 cli_session_actions[s].action = 0;
2953 if (a & CLI_SESS_KILL)
2954 {
2955 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2956 sessionshutdown(s, "Requested by administrator.", 3, 0);
2957 a = 0; // dead, no need to check for other actions
2958 s_actions++;
2959 }
2960
2961 if (a & CLI_SESS_NOSNOOP)
2962 {
2963 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2964 session[s].snoop_ip = 0;
2965 session[s].snoop_port = 0;
2966 s_actions++;
2967 send++;
2968 }
2969 else if (a & CLI_SESS_SNOOP)
2970 {
2971 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2972 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2973 cli_session_actions[s].snoop_port);
2974
2975 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2976 session[s].snoop_port = cli_session_actions[s].snoop_port;
2977 s_actions++;
2978 send++;
2979 }
2980
2981 if (a & CLI_SESS_NOTHROTTLE)
2982 {
2983 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2984 throttle_session(s, 0, 0);
2985 s_actions++;
2986 send++;
2987 }
2988 else if (a & CLI_SESS_THROTTLE)
2989 {
2990 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2991 cli_session_actions[s].throttle_in,
2992 cli_session_actions[s].throttle_out);
2993
2994 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2995 s_actions++;
2996 send++;
2997 }
2998
2999 if (a & CLI_SESS_NOFILTER)
3000 {
3001 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3002 filter_session(s, 0, 0);
3003 s_actions++;
3004 send++;
3005 }
3006 else if (a & CLI_SESS_FILTER)
3007 {
3008 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3009 cli_session_actions[s].filter_in,
3010 cli_session_actions[s].filter_out);
3011
3012 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3013 s_actions++;
3014 send++;
3015 }
3016
3017 if (send)
3018 cluster_send_session(s);
3019 }
3020
3021 // RADIUS interim accounting
3022 if (config->radius_accounting && config->radius_interim > 0
3023 && session[s].ip && !session[s].walled_garden
3024 && !sess_local[s].radius // RADIUS already in progress
3025 && time_now - sess_local[s].last_interim >= config->radius_interim)
3026 {
3027 int rad = radiusnew(s);
3028 if (!rad)
3029 {
3030 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3031 STAT(radius_overflow);
3032 continue;
3033 }
3034
3035 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3036 session[s].user, session[s].unique_id);
3037
3038 radiussend(rad, RADIUSINTERIM);
3039 sess_local[s].last_interim = time_now;
3040 s_actions++;
3041 }
3042 }
3043
3044 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3045 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3046 }
3047
3048 //
3049 // Are we in the middle of a tunnel update, or radius
3050 // requests??
3051 //
3052 static int still_busy(void)
3053 {
3054 int i;
3055 static clockt last_talked = 0;
3056 static clockt start_busy_wait = 0;
3057
3058 if (!config->cluster_iam_master)
3059 {
3060 #ifdef BGP
3061 static time_t stopped_bgp = 0;
3062 if (bgp_configured)
3063 {
3064 if (!stopped_bgp)
3065 {
3066 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3067
3068 for (i = 0; i < BGP_NUM_PEERS; i++)
3069 if (bgp_peers[i].state == Established)
3070 bgp_stop(&bgp_peers[i]);
3071
3072 stopped_bgp = time_now;
3073
3074 // we don't want to become master
3075 cluster_send_ping(0);
3076
3077 return 1;
3078 }
3079
3080 if (time_now < (stopped_bgp + QUIT_DELAY))
3081 return 1;
3082 }
3083 #endif /* BGP */
3084
3085 return 0;
3086 }
3087
3088 if (main_quit == QUIT_SHUTDOWN)
3089 {
3090 static int dropped = 0;
3091 if (!dropped)
3092 {
3093 int i;
3094
3095 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3096 for (i = 1; i < MAXTUNNEL; i++)
3097 if (tunnel[i].ip || tunnel[i].state)
3098 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3099
3100 dropped = 1;
3101 }
3102 }
3103
3104 if (start_busy_wait == 0)
3105 start_busy_wait = TIME;
3106
3107 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3108 {
3109 if (!tunnel[i].controlc)
3110 continue;
3111
3112 if (last_talked != TIME)
3113 {
3114 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3115 last_talked = TIME;
3116 }
3117 return 1;
3118 }
3119
3120 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3121 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3122 {
3123 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3124 return 0;
3125 }
3126
3127 for (i = 1; i < MAXRADIUS; i++)
3128 {
3129 if (radius[i].state == RADIUSNULL)
3130 continue;
3131 if (radius[i].state == RADIUSWAIT)
3132 continue;
3133
3134 if (last_talked != TIME)
3135 {
3136 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3137 last_talked = TIME;
3138 }
3139 return 1;
3140 }
3141
3142 return 0;
3143 }
3144
3145 #ifdef HAVE_EPOLL
3146 # include <sys/epoll.h>
3147 #else
3148 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3149 # include "fake_epoll.h"
3150 #endif
3151
3152 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3153 #define BASE_FDS 6
3154
3155 // additional polled fds
3156 #ifdef BGP
3157 # define EXTRA_FDS BGP_NUM_PEERS
3158 #else
3159 # define EXTRA_FDS 0
3160 #endif
3161
3162 // main loop - gets packets on tun or udp and processes them
3163 static void mainloop(void)
3164 {
3165 int i;
3166 uint8_t buf[65536];
3167 clockt next_cluster_ping = 0; // send initial ping immediately
3168 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3169 int maxevent = sizeof(events)/sizeof(*events);
3170
3171 if ((epollfd = epoll_create(maxevent)) < 0)
3172 {
3173 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3174 exit(1);
3175 }
3176
3177 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3178 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3179
3180 /* setup our fds to poll for input */
3181 {
3182 static struct event_data d[BASE_FDS];
3183 struct epoll_event e;
3184
3185 e.events = EPOLLIN;
3186 i = 0;
3187
3188 d[i].type = FD_TYPE_CLI;
3189 e.data.ptr = &d[i++];
3190 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3191
3192 d[i].type = FD_TYPE_CLUSTER;
3193 e.data.ptr = &d[i++];
3194 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3195
3196 d[i].type = FD_TYPE_TUN;
3197 e.data.ptr = &d[i++];
3198 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3199
3200 d[i].type = FD_TYPE_UDP;
3201 e.data.ptr = &d[i++];
3202 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3203
3204 d[i].type = FD_TYPE_CONTROL;
3205 e.data.ptr = &d[i++];
3206 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3207
3208 d[i].type = FD_TYPE_DAE;
3209 e.data.ptr = &d[i++];
3210 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3211 }
3212
3213 #ifdef BGP
3214 signal(SIGPIPE, SIG_IGN);
3215 bgp_setup(config->as_number);
3216 if (config->bind_address)
3217 bgp_add_route(config->bind_address, 0xffffffff);
3218
3219 for (i = 0; i < BGP_NUM_PEERS; i++)
3220 {
3221 if (config->neighbour[i].name[0])
3222 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3223 config->neighbour[i].as, config->neighbour[i].keepalive,
3224 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3225 }
3226 #endif /* BGP */
3227
3228 while (!main_quit || still_busy())
3229 {
3230 int more = 0;
3231 int n;
3232
3233
3234 if (main_reload)
3235 {
3236 main_reload = 0;
3237 read_config_file();
3238 config->reload_config++;
3239 }
3240
3241 if (config->reload_config)
3242 {
3243 config->reload_config = 0;
3244 update_config();
3245 }
3246
3247 #ifdef BGP
3248 bgp_set_poll();
3249 #endif /* BGP */
3250
3251 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3252 STAT(select_called);
3253
3254 TIME = now(NULL);
3255 if (n < 0)
3256 {
3257 if (errno == EINTR ||
3258 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3259 continue;
3260
3261 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3262 break; // exit
3263 }
3264
3265 if (n)
3266 {
3267 struct sockaddr_in addr;
3268 socklen_t alen;
3269 int c, s;
3270 int udp_ready = 0;
3271 int tun_ready = 0;
3272 int cluster_ready = 0;
3273 int udp_pkts = 0;
3274 int tun_pkts = 0;
3275 int cluster_pkts = 0;
3276 #ifdef BGP
3277 uint32_t bgp_events[BGP_NUM_PEERS];
3278 memset(bgp_events, 0, sizeof(bgp_events));
3279 #endif /* BGP */
3280
3281 for (c = n, i = 0; i < c; i++)
3282 {
3283 struct event_data *d = events[i].data.ptr;
3284 switch (d->type)
3285 {
3286 case FD_TYPE_CLI: // CLI connections
3287 {
3288 int cli;
3289
3290 alen = sizeof(addr);
3291 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3292 {
3293 cli_do(cli);
3294 close(cli);
3295 }
3296 else
3297 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3298
3299 n--;
3300 break;
3301 }
3302
3303 // these are handled below, with multiple interleaved reads
3304 case FD_TYPE_CLUSTER: cluster_ready++; break;
3305 case FD_TYPE_TUN: tun_ready++; break;
3306 case FD_TYPE_UDP: udp_ready++; break;
3307
3308 case FD_TYPE_CONTROL: // nsctl commands
3309 alen = sizeof(addr);
3310 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3311 n--;
3312 break;
3313
3314 case FD_TYPE_DAE: // DAE requests
3315 alen = sizeof(addr);
3316 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3317 n--;
3318 break;
3319
3320 case FD_TYPE_RADIUS: // RADIUS response
3321 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3322 if (s >= 0 && config->cluster_iam_master)
3323 processrad(buf, s, d->index);
3324
3325 n--;
3326 break;
3327
3328 #ifdef BGP
3329 case FD_TYPE_BGP:
3330 bgp_events[d->index] = events[i].events;
3331 n--;
3332 break;
3333 #endif /* BGP */
3334
3335 default:
3336 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3337 }
3338 }
3339
3340 #ifdef BGP
3341 bgp_process(bgp_events);
3342 #endif /* BGP */
3343
3344 for (c = 0; n && c < config->multi_read_count; c++)
3345 {
3346 // L2TP
3347 if (udp_ready)
3348 {
3349 alen = sizeof(addr);
3350 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3351 {
3352 processudp(buf, s, &addr);
3353 udp_pkts++;
3354 }
3355 else
3356 {
3357 udp_ready = 0;
3358 n--;
3359 }
3360 }
3361
3362 // incoming IP
3363 if (tun_ready)
3364 {
3365 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3366 {
3367 processtun(buf, s);
3368 tun_pkts++;
3369 }
3370 else
3371 {
3372 tun_ready = 0;
3373 n--;
3374 }
3375 }
3376
3377 // cluster
3378 if (cluster_ready)
3379 {
3380 alen = sizeof(addr);
3381 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3382 {
3383 processcluster(buf, s, addr.sin_addr.s_addr);
3384 cluster_pkts++;
3385 }
3386 else
3387 {
3388 cluster_ready = 0;
3389 n--;
3390 }
3391 }
3392 }
3393
3394 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3395 STAT(multi_read_used);
3396
3397 if (c >= config->multi_read_count)
3398 {
3399 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3400 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3401
3402 STAT(multi_read_exceeded);
3403 more++;
3404 }
3405 }
3406
3407 if (time_changed)
3408 {
3409 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
3410
3411 // Log current traffic stats
3412 snprintf(config->bandwidth, sizeof(config->bandwidth),
3413 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3414 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
3415 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
3416 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
3417
3418 udp_tx = udp_rx = 0;
3419 udp_rx_pkt = eth_rx_pkt = 0;
3420 eth_tx = eth_rx = 0;
3421 time_changed = 0;
3422
3423 if (config->dump_speed)
3424 printf("%s\n", config->bandwidth);
3425
3426 // Update the internal time counter
3427 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3428
3429 {
3430 // Run timer hooks
3431 struct param_timer p = { time_now };
3432 run_plugins(PLUGIN_TIMER, &p);
3433 }
3434 }
3435
3436 // Runs on every machine (master and slaves).
3437 if (next_cluster_ping <= TIME)
3438 {
3439 // Check to see which of the cluster is still alive..
3440
3441 cluster_send_ping(basetime); // Only does anything if we're a slave
3442 cluster_check_master(); // ditto.
3443
3444 cluster_heartbeat(); // Only does anything if we're a master.
3445 cluster_check_slaves(); // ditto.
3446
3447 master_update_counts(); // If we're a slave, send our byte counters to our master.
3448
3449 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3450 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3451 else
3452 next_cluster_ping = TIME + config->cluster_hb_interval;
3453 }
3454
3455 if (!config->cluster_iam_master)
3456 continue;
3457
3458 // Run token bucket filtering queue..
3459 // Only run it every 1/10th of a second.
3460 {
3461 static clockt last_run = 0;
3462 if (last_run != TIME)
3463 {
3464 last_run = TIME;
3465 tbf_run_timer();
3466 }
3467 }
3468
3469 // Handle timeouts, retries etc.
3470 {
3471 static double last_clean = 0;
3472 double this_clean;
3473 double diff;
3474
3475 TIME = now(&this_clean);
3476 diff = this_clean - last_clean;
3477
3478 // Run during idle time (after we've handled
3479 // all incoming packets) or every 1/10th sec
3480 if (!more || diff > 0.1)
3481 {
3482 regular_cleanups(diff);
3483 last_clean = this_clean;
3484 }
3485 }
3486
3487 if (*config->accounting_dir)
3488 {
3489 static clockt next_acct = 0;
3490 static clockt next_shut_acct = 0;
3491
3492 if (next_acct <= TIME)
3493 {
3494 // Dump accounting data
3495 next_acct = TIME + ACCT_TIME;
3496 next_shut_acct = TIME + ACCT_SHUT_TIME;
3497 dump_acct_info(1);
3498 }
3499 else if (next_shut_acct <= TIME)
3500 {
3501 // Dump accounting data for shutdown sessions
3502 next_shut_acct = TIME + ACCT_SHUT_TIME;
3503 if (shut_acct_n)
3504 dump_acct_info(0);
3505 }
3506 }
3507 }
3508
3509 // Are we the master and shutting down??
3510 if (config->cluster_iam_master)
3511 cluster_heartbeat(); // Flush any queued changes..
3512
3513 // Ok. Notify everyone we're shutting down. If we're
3514 // the master, this will force an election.
3515 cluster_send_ping(0);
3516
3517 //
3518 // Important!!! We MUST not process any packets past this point!
3519 LOG(1, 0, 0, "Shutdown complete\n");
3520 }
3521
3522 static void stripdomain(char *host)
3523 {
3524 char *p;
3525
3526 if ((p = strchr(host, '.')))
3527 {
3528 char *domain = 0;
3529 char _domain[1024];
3530
3531 // strip off domain
3532 FILE *resolv = fopen("/etc/resolv.conf", "r");
3533 if (resolv)
3534 {
3535 char buf[1024];
3536 char *b;
3537
3538 while (fgets(buf, sizeof(buf), resolv))
3539 {
3540 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3541 continue;
3542
3543 if (!isspace(buf[6]))
3544 continue;
3545
3546 b = buf + 7;
3547 while (isspace(*b)) b++;
3548
3549 if (*b)
3550 {
3551 char *d = b;
3552 while (*b && !isspace(*b)) b++;
3553 *b = 0;
3554 if (buf[0] == 'd') // domain is canonical
3555 {
3556 domain = d;
3557 break;
3558 }
3559
3560 // first search line
3561 if (!domain)
3562 {
3563 // hold, may be subsequent domain line
3564 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3565 domain = _domain;
3566 }
3567 }
3568 }
3569
3570 fclose(resolv);
3571 }
3572
3573 if (domain)
3574 {
3575 int hl = strlen(host);
3576 int dl = strlen(domain);
3577 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3578 host[hl -dl - 1] = 0;
3579 }
3580 else
3581 {
3582 *p = 0; // everything after first dot
3583 }
3584 }
3585 }
3586
3587 // Init data structures
3588 static void initdata(int optdebug, char *optconfig)
3589 {
3590 int i;
3591
3592 if (!(config = shared_malloc(sizeof(configt))))
3593 {
3594 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3595 exit(1);
3596 }
3597
3598 memset(config, 0, sizeof(configt));
3599 time(&config->start_time);
3600 strncpy(config->config_file, optconfig, strlen(optconfig));
3601 config->debug = optdebug;
3602 config->num_tbfs = MAXTBFS;
3603 config->rl_rate = 28; // 28kbps
3604 config->cluster_mcast_ttl = 1;
3605 config->cluster_master_min_adv = 1;
3606 config->ppp_restart_time = 3;
3607 config->ppp_max_configure = 10;
3608 config->ppp_max_failure = 5;
3609 strcpy(config->random_device, RANDOMDEVICE);
3610
3611 log_stream = stderr;
3612
3613 #ifdef RINGBUFFER
3614 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3615 {
3616 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3617 exit(1);
3618 }
3619 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3620 #endif
3621
3622 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3623 {
3624 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3625 exit(1);
3626 }
3627 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3628 {
3629 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3630 exit(1);
3631 }
3632 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3633 {
3634 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3635 exit(1);
3636 }
3637
3638 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3639 {
3640 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3641 exit(1);
3642 }
3643
3644 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3645 {
3646 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3647 exit(1);
3648 }
3649
3650 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3651 {
3652 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3653 exit(1);
3654 }
3655
3656 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3657 {
3658 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3659 exit(1);
3660 }
3661 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3662
3663 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3664 {
3665 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3666 exit(1);
3667 }
3668 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3669
3670 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3671 {
3672 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3673 exit(1);
3674 }
3675 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3676
3677 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3678 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3679 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3680 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3681
3682 // Put all the sessions on the free list marked as undefined.
3683 for (i = 1; i < MAXSESSION; i++)
3684 {
3685 session[i].next = i + 1;
3686 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3687 }
3688 session[MAXSESSION - 1].next = 0;
3689 sessionfree = 1;
3690
3691 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3692 for (i = 1; i < MAXTUNNEL; i++)
3693 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3694
3695 if (!*hostname)
3696 {
3697 // Grab my hostname unless it's been specified
3698 gethostname(hostname, sizeof(hostname));
3699 stripdomain(hostname);
3700 }
3701
3702 _statistics->start_time = _statistics->last_reset = time(NULL);
3703
3704 #ifdef BGP
3705 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3706 {
3707 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3708 exit(1);
3709 }
3710 #endif /* BGP */
3711 }
3712
3713 static int assign_ip_address(sessionidt s)
3714 {
3715 uint32_t i;
3716 int best = -1;
3717 time_t best_time = time_now;
3718 char *u = session[s].user;
3719 char reuse = 0;
3720
3721
3722 CSTAT(assign_ip_address);
3723
3724 for (i = 1; i < ip_pool_size; i++)
3725 {
3726 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3727 continue;
3728
3729 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3730 {
3731 best = i;
3732 reuse = 1;
3733 break;
3734 }
3735
3736 if (ip_address_pool[i].last < best_time)
3737 {
3738 best = i;
3739 if (!(best_time = ip_address_pool[i].last))
3740 break; // never used, grab this one
3741 }
3742 }
3743
3744 if (best < 0)
3745 {
3746 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3747 return 0;
3748 }
3749
3750 session[s].ip = ip_address_pool[best].address;
3751 session[s].ip_pool_index = best;
3752 ip_address_pool[best].assigned = 1;
3753 ip_address_pool[best].last = time_now;
3754 ip_address_pool[best].session = s;
3755 if (session[s].walled_garden)
3756 /* Don't track addresses of users in walled garden (note: this
3757 means that their address isn't "sticky" even if they get
3758 un-gardened). */
3759 ip_address_pool[best].user[0] = 0;
3760 else
3761 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3762
3763 STAT(ip_allocated);
3764 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3765 reuse ? "Reusing" : "Allocating", best);
3766
3767 return 1;
3768 }
3769
3770 static void free_ip_address(sessionidt s)
3771 {
3772 int i = session[s].ip_pool_index;
3773
3774
3775 CSTAT(free_ip_address);
3776
3777 if (!session[s].ip)
3778 return; // what the?
3779
3780 if (i < 0) // Is this actually part of the ip pool?
3781 i = 0;
3782
3783 STAT(ip_freed);
3784 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3785 session[s].ip = 0;
3786 ip_address_pool[i].assigned = 0;
3787 ip_address_pool[i].session = 0;
3788 ip_address_pool[i].last = time_now;
3789 }
3790
3791 //
3792 // Fsck the address pool against the session table.
3793 // Normally only called when we become a master.
3794 //
3795 // This isn't perfect: We aren't keep tracking of which
3796 // users used to have an IP address.
3797 //
3798 void rebuild_address_pool(void)
3799 {
3800 int i;
3801
3802 //
3803 // Zero the IP pool allocation, and build
3804 // a map from IP address to pool index.
3805 for (i = 1; i < MAXIPPOOL; ++i)
3806 {
3807 ip_address_pool[i].assigned = 0;
3808 ip_address_pool[i].session = 0;
3809 if (!ip_address_pool[i].address)
3810 continue;
3811
3812 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3813 }
3814
3815 for (i = 0; i < MAXSESSION; ++i)
3816 {
3817 int ipid;
3818 if (!(session[i].opened && session[i].ip))
3819 continue;
3820
3821 ipid = - lookup_ipmap(htonl(session[i].ip));
3822
3823 if (session[i].ip_pool_index < 0)
3824 {
3825 // Not allocated out of the pool.
3826 if (ipid < 1) // Not found in the pool either? good.
3827 continue;
3828
3829 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3830 i, fmtaddr(session[i].ip, 0), ipid);
3831
3832 // Fall through and process it as part of the pool.
3833 }
3834
3835
3836 if (ipid > MAXIPPOOL || ipid < 0)
3837 {
3838 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3839 ipid = -1;
3840 session[i].ip_pool_index = ipid;
3841 continue;
3842 }
3843
3844 ip_address_pool[ipid].assigned = 1;
3845 ip_address_pool[ipid].session = i;
3846 ip_address_pool[ipid].last = time_now;
3847 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3848 session[i].ip_pool_index = ipid;
3849 cache_ipmap(session[i].ip, i); // Fix the ip map.
3850 }
3851 }
3852
3853 //
3854 // Fix the address pool to match a changed session.
3855 // (usually when the master sends us an update).
3856 static void fix_address_pool(int sid)
3857 {
3858 int ipid;
3859
3860 ipid = session[sid].ip_pool_index;
3861
3862 if (ipid > ip_pool_size)
3863 return; // Ignore it. rebuild_address_pool will fix it up.
3864
3865 if (ip_address_pool[ipid].address != session[sid].ip)
3866 return; // Just ignore it. rebuild_address_pool will take care of it.
3867
3868 ip_address_pool[ipid].assigned = 1;
3869 ip_address_pool[ipid].session = sid;
3870 ip_address_pool[ipid].last = time_now;
3871 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3872 }
3873
3874 //
3875 // Add a block of addresses to the IP pool to hand out.
3876 //
3877 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3878 {
3879 int i;
3880 if (mask == 0)
3881 mask = 0xffffffff; // Host route only.
3882
3883 addr &= mask;
3884
3885 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3886 return ;
3887
3888 for (i = addr ;(i & mask) == addr; ++i)
3889 {
3890 if ((i & 0xff) == 0 || (i&0xff) == 255)
3891 continue; // Skip 0 and broadcast addresses.
3892
3893 ip_address_pool[ip_pool_size].address = i;
3894 ip_address_pool[ip_pool_size].assigned = 0;
3895 ++ip_pool_size;
3896 if (ip_pool_size >= MAXIPPOOL)
3897 {
3898 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3899 return;
3900 }
3901 }
3902 }
3903
3904 // Initialize the IP address pool
3905 static void initippool()
3906 {
3907 FILE *f;
3908 char *p;
3909 char buf[4096];
3910 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3911
3912 if (!(f = fopen(IPPOOLFILE, "r")))
3913 {
3914 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3915 exit(1);
3916 }
3917
3918 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3919 {
3920 char *pool = buf;
3921 buf[4095] = 0; // Force it to be zero terminated/
3922
3923 if (*buf == '#' || *buf == '\n')
3924 continue; // Skip comments / blank lines
3925 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3926 if ((p = (char *)strchr(buf, ':')))
3927 {
3928 in_addr_t src;
3929 *p = '\0';
3930 src = inet_addr(buf);
3931 if (src == INADDR_NONE)
3932 {
3933 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3934 exit(1);
3935 }
3936 // This entry is for a specific IP only
3937 if (src != config->bind_address)
3938 continue;
3939 *p = ':';
3940 pool = p+1;
3941 }
3942 if ((p = (char *)strchr(pool, '/')))
3943 {
3944 // It's a range
3945 int numbits = 0;
3946 in_addr_t start = 0, mask = 0;
3947
3948 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3949 *p++ = 0;
3950 if (!*p || !(numbits = atoi(p)))
3951 {
3952 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3953 continue;
3954 }
3955 start = ntohl(inet_addr(pool));
3956 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3957
3958 // Add a static route for this pool
3959 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3960 fmtaddr(htonl(start), 0), 32 + mask);
3961
3962 routeset(0, start, mask, 0, 1);
3963
3964 add_to_ip_pool(start, mask);
3965 }
3966 else
3967 {
3968 // It's a single ip address
3969 add_to_ip_pool(inet_addr(pool), 0);
3970 }
3971 }
3972 fclose(f);
3973 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3974 }
3975
3976 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3977 {
3978 struct sockaddr_in snoop_addr = {0};
3979 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3980 return;
3981
3982 snoop_addr.sin_family = AF_INET;
3983 snoop_addr.sin_addr.s_addr = destination;
3984 snoop_addr.sin_port = ntohs(port);
3985
3986 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3987 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3988 htons(snoop_addr.sin_port));
3989
3990 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3991 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3992
3993 STAT(packets_snooped);
3994 }
3995
3996 static int dump_session(FILE **f, sessiont *s)
3997 {
3998 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3999 return 1;
4000
4001 if (!*f)
4002 {
4003 char filename[1024];
4004 char timestr[64];
4005 time_t now = time(NULL);
4006
4007 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4008 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4009
4010 if (!(*f = fopen(filename, "w")))
4011 {
4012 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4013 return 0;
4014 }
4015
4016 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4017 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4018 "# host: %s\n"
4019 "# endpoint: %s\n"
4020 "# time: %ld\n"
4021 "# uptime: %ld\n"
4022 "# format: username ip qos uptxoctets downrxoctets\n",
4023 hostname,
4024 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
4025 now,
4026 now - basetime);
4027 }
4028
4029 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4030 fprintf(*f, "%s %s %d %u %u\n",
4031 s->user, // username
4032 fmtaddr(htonl(s->ip), 0), // ip
4033 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4034 (uint32_t) s->cin_delta, // uptxoctets
4035 (uint32_t) s->cout_delta); // downrxoctets
4036
4037 s->cin_delta = s->cout_delta = 0;
4038
4039 return 1;
4040 }
4041
4042 static void dump_acct_info(int all)
4043 {
4044 int i;
4045 FILE *f = NULL;
4046
4047
4048 CSTAT(dump_acct_info);
4049
4050 if (shut_acct_n)
4051 {
4052 for (i = 0; i < shut_acct_n; i++)
4053 dump_session(&f, &shut_acct[i]);
4054
4055 shut_acct_n = 0;
4056 }
4057
4058 if (all)
4059 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4060 dump_session(&f, &session[i]);
4061
4062 if (f)
4063 fclose(f);
4064 }
4065
4066 // Main program
4067 int main(int argc, char *argv[])
4068 {
4069 int i;
4070 int optdebug = 0;
4071 char *optconfig = CONFIGFILE;
4072
4073 time(&basetime); // start clock
4074
4075 // scan args
4076 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4077 {
4078 switch (i)
4079 {
4080 case 'd':
4081 if (fork()) exit(0);
4082 setsid();
4083 freopen("/dev/null", "r", stdin);
4084 freopen("/dev/null", "w", stdout);
4085 freopen("/dev/null", "w", stderr);
4086 break;
4087 case 'v':
4088 optdebug++;
4089 break;
4090 case 'c':
4091 optconfig = optarg;
4092 break;
4093 case 'h':
4094 snprintf(hostname, sizeof(hostname), "%s", optarg);
4095 break;
4096 default:
4097 printf("Args are:\n"
4098 "\t-d\t\tDetach from terminal\n"
4099 "\t-c <file>\tConfig file\n"
4100 "\t-h <hostname>\tForce hostname\n"
4101 "\t-v\t\tDebug\n");
4102
4103 return (0);
4104 break;
4105 }
4106 }
4107
4108 // Start the timer routine off
4109 time(&time_now);
4110 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4111
4112 initplugins();
4113 initdata(optdebug, optconfig);
4114
4115 init_cli(hostname);
4116 read_config_file();
4117 update_config();
4118 init_tbf(config->num_tbfs);
4119
4120 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4121 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4122 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4123 {
4124 struct rlimit rlim;
4125 rlim.rlim_cur = RLIM_INFINITY;
4126 rlim.rlim_max = RLIM_INFINITY;
4127 // Remove the maximum core size
4128 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4129 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4130
4131 // Make core dumps go to /tmp
4132 chdir("/tmp");
4133 }
4134
4135 if (config->scheduler_fifo)
4136 {
4137 int ret;
4138 struct sched_param params = {0};
4139 params.sched_priority = 1;
4140
4141 if (get_nprocs() < 2)
4142 {
4143 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4144 config->scheduler_fifo = 0;
4145 }
4146 else
4147 {
4148 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4149 {
4150 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4151 }
4152 else
4153 {
4154 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4155 config->scheduler_fifo = 0;
4156 }
4157 }
4158 }
4159
4160 /* Set up the cluster communications port. */
4161 if (cluster_init() < 0)
4162 exit(1);
4163
4164 inittun();
4165 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4166
4167 initudp();
4168 initrad();
4169 initippool();
4170
4171 // seed prng
4172 {
4173 unsigned seed = time_now ^ getpid();
4174 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4175 srand(seed);
4176 }
4177
4178 signal(SIGHUP, sighup_handler);
4179 signal(SIGCHLD, sigchild_handler);
4180 signal(SIGTERM, shutdown_handler);
4181 signal(SIGINT, shutdown_handler);
4182 signal(SIGQUIT, shutdown_handler);
4183
4184 // Prevent us from getting paged out
4185 if (config->lock_pages)
4186 {
4187 if (!mlockall(MCL_CURRENT))
4188 LOG(1, 0, 0, "Locking pages into memory\n");
4189 else
4190 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4191 }
4192
4193 // Drop privileges here
4194 if (config->target_uid > 0 && geteuid() == 0)
4195 setuid(config->target_uid);
4196
4197 mainloop();
4198
4199 /* remove plugins (so cleanup code gets run) */
4200 plugins_done();
4201
4202 // Remove the PID file if we wrote it
4203 if (config->wrote_pid && *config->pid_file == '/')
4204 unlink(config->pid_file);
4205
4206 /* kill CLI children */
4207 signal(SIGTERM, SIG_IGN);
4208 kill(0, SIGTERM);
4209 return 0;
4210 }
4211
4212 static void sighup_handler(int sig)
4213 {
4214 main_reload++;
4215 }
4216
4217 static void shutdown_handler(int sig)
4218 {
4219 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4220 }
4221
4222 static void sigchild_handler(int sig)
4223 {
4224 while (waitpid(-1, NULL, WNOHANG) > 0)
4225 ;
4226 }
4227
4228 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4229 {
4230 MD5_CTX ctx;
4231 *challenge_response = NULL;
4232
4233 if (!*config->l2tp_secret)
4234 {
4235 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4236 return;
4237 }
4238
4239 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4240
4241 *challenge_response = calloc(17, 1);
4242
4243 MD5_Init(&ctx);
4244 MD5_Update(&ctx, &id, 1);
4245 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4246 MD5_Update(&ctx, challenge, challenge_length);
4247 MD5_Final(*challenge_response, &ctx);
4248
4249 return;
4250 }
4251
4252 static int facility_value(char *name)
4253 {
4254 int i;
4255 for (i = 0; facilitynames[i].c_name; i++)
4256 {
4257 if (strcmp(facilitynames[i].c_name, name) == 0)
4258 return facilitynames[i].c_val;
4259 }
4260 return 0;
4261 }
4262
4263 static void update_config()
4264 {
4265 int i;
4266 char *p;
4267 static int timeout = 0;
4268 static int interval = 0;
4269
4270 // Update logging
4271 closelog();
4272 syslog_log = 0;
4273 if (log_stream)
4274 {
4275 if (log_stream != stderr)
4276 fclose(log_stream);
4277
4278 log_stream = NULL;
4279 }
4280
4281 if (*config->log_filename)
4282 {
4283 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4284 {
4285 char *p = config->log_filename + 7;
4286 if (*p)
4287 {
4288 openlog("l2tpns", LOG_PID, facility_value(p));
4289 syslog_log = 1;
4290 }
4291 }
4292 else if (strchr(config->log_filename, '/') == config->log_filename)
4293 {
4294 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4295 {
4296 fseek(log_stream, 0, SEEK_END);
4297 setbuf(log_stream, NULL);
4298 }
4299 else
4300 {
4301 log_stream = stderr;
4302 setbuf(log_stream, NULL);
4303 }
4304 }
4305 }
4306 else
4307 {
4308 log_stream = stderr;
4309 setbuf(log_stream, NULL);
4310 }
4311
4312 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4313 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4314
4315 if (config->l2tp_mtu <= 0) config->l2tp_mtu = PPPMTU;
4316 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4317 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4318
4319 // reset MRU/MSS globals
4320 MRU = config->l2tp_mtu - L2TP_HDRS;
4321 MSS = MRU - TCP_HDRS;
4322
4323 // Update radius
4324 config->numradiusservers = 0;
4325 for (i = 0; i < MAXRADSERVER; i++)
4326 if (config->radiusserver[i])
4327 {
4328 config->numradiusservers++;
4329 // Set radius port: if not set, take the port from the
4330 // first radius server. For the first radius server,
4331 // take the #defined default value from l2tpns.h
4332
4333 // test twice, In case someone works with
4334 // a secondary radius server without defining
4335 // a primary one, this will work even then.
4336 if (i > 0 && !config->radiusport[i])
4337 config->radiusport[i] = config->radiusport[i-1];
4338 if (!config->radiusport[i])
4339 config->radiusport[i] = RADPORT;
4340 }
4341
4342 if (!config->numradiusservers)
4343 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4344
4345 // parse radius_authtypes_s
4346 config->radius_authtypes = config->radius_authprefer = 0;
4347 p = config->radius_authtypes_s;
4348 while (p && *p)
4349 {
4350 char *s = strpbrk(p, " \t,");
4351 int type = 0;
4352
4353 if (s)
4354 {
4355 *s++ = 0;
4356 while (*s == ' ' || *s == '\t')
4357 s++;
4358
4359 if (!*s)
4360 s = 0;
4361 }
4362
4363 if (!strncasecmp("chap", p, strlen(p)))
4364 type = AUTHCHAP;
4365 else if (!strncasecmp("pap", p, strlen(p)))
4366 type = AUTHPAP;
4367 else
4368 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4369
4370 config->radius_authtypes |= type;
4371 if (!config->radius_authprefer)
4372 config->radius_authprefer = type;
4373
4374 p = s;
4375 }
4376
4377 if (!config->radius_authtypes)
4378 {
4379 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4380 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4381 }
4382
4383 // normalise radius_authtypes_s
4384 if (config->radius_authprefer == AUTHPAP)
4385 {
4386 strcpy(config->radius_authtypes_s, "pap");
4387 if (config->radius_authtypes & AUTHCHAP)
4388 strcat(config->radius_authtypes_s, ", chap");
4389 }
4390 else
4391 {
4392 strcpy(config->radius_authtypes_s, "chap");
4393 if (config->radius_authtypes & AUTHPAP)
4394 strcat(config->radius_authtypes_s, ", pap");
4395 }
4396
4397 if (!config->radius_dae_port)
4398 config->radius_dae_port = DAEPORT;
4399
4400 // re-initialise the random number source
4401 initrandom(config->random_device);
4402
4403 // Update plugins
4404 for (i = 0; i < MAXPLUGINS; i++)
4405 {
4406 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4407 continue;
4408
4409 if (*config->plugins[i])
4410 {
4411 // Plugin added
4412 add_plugin(config->plugins[i]);
4413 }
4414 else if (*config->old_plugins[i])
4415 {
4416 // Plugin removed
4417 remove_plugin(config->old_plugins[i]);
4418 }
4419 }
4420
4421 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4422 if (!config->multi_read_count) config->multi_read_count = 10;
4423 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4424 if (!*config->cluster_interface)
4425 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4426
4427 if (!config->cluster_hb_interval)
4428 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4429
4430 if (!config->cluster_hb_timeout)
4431 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4432
4433 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4434 {
4435 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4436 // late, ensure we're sufficiently larger than that
4437 int t = 4 * config->cluster_hb_interval + 11;
4438
4439 if (config->cluster_hb_timeout < t)
4440 {
4441 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4442 config->cluster_hb_timeout = t;
4443 }
4444
4445 // Push timing changes to the slaves immediately if we're the master
4446 if (config->cluster_iam_master)
4447 cluster_heartbeat();
4448
4449 interval = config->cluster_hb_interval;
4450 timeout = config->cluster_hb_timeout;
4451 }
4452
4453 // Write PID file
4454 if (*config->pid_file == '/' && !config->wrote_pid)
4455 {
4456 FILE *f;
4457 if ((f = fopen(config->pid_file, "w")))
4458 {
4459 fprintf(f, "%d\n", getpid());
4460 fclose(f);
4461 config->wrote_pid = 1;
4462 }
4463 else
4464 {
4465 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4466 }
4467 }
4468 }
4469
4470 static void read_config_file()
4471 {
4472 FILE *f;
4473
4474 if (!config->config_file) return;
4475 if (!(f = fopen(config->config_file, "r")))
4476 {
4477 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4478 return;
4479 }
4480
4481 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4482 cli_do_file(f);
4483 LOG(3, 0, 0, "Done reading config file\n");
4484 fclose(f);
4485 }
4486
4487 int sessionsetup(sessionidt s, tunnelidt t)
4488 {
4489 // A session now exists, set it up
4490 in_addr_t ip;
4491 char *user;
4492 sessionidt i;
4493 int r;
4494
4495 CSTAT(sessionsetup);
4496
4497 LOG(3, s, t, "Doing session setup for session\n");
4498
4499 if (!session[s].ip)
4500 {
4501 assign_ip_address(s);
4502 if (!session[s].ip)
4503 {
4504 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4505 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4506 return 0;
4507 }
4508 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4509 fmtaddr(htonl(session[s].ip), 0));
4510 }
4511
4512
4513 // Make sure this is right
4514 session[s].tunnel = t;
4515
4516 // zap old sessions with same IP and/or username
4517 // Don't kill gardened sessions - doing so leads to a DoS
4518 // from someone who doesn't need to know the password
4519 {
4520 ip = session[s].ip;
4521 user = session[s].user;
4522 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4523 {
4524 if (i == s) continue;
4525 if (!session[s].opened) continue;
4526 if (ip == session[i].ip)
4527 {
4528 sessionkill(i, "Duplicate IP address");
4529 continue;
4530 }
4531
4532 if (config->allow_duplicate_users) continue;
4533 if (session[s].walled_garden || session[i].walled_garden) continue;
4534 if (!strcasecmp(user, session[i].user))
4535 sessionkill(i, "Duplicate session for users");
4536 }
4537 }
4538
4539 {
4540 int routed = 0;
4541
4542 // Add the route for this session.
4543 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4544 {
4545 if ((session[s].ip & session[s].route[r].mask) ==
4546 (session[s].route[r].ip & session[s].route[r].mask))
4547 routed++;
4548
4549 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4550 }
4551
4552 // Static IPs need to be routed if not already
4553 // convered by a Framed-Route. Anything else is part
4554 // of the IP address pool and is already routed, it
4555 // just needs to be added to the IP cache.
4556 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4557 if (session[s].ip_pool_index == -1) // static ip
4558 {
4559 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4560 }
4561 else
4562 cache_ipmap(session[s].ip, s);
4563 }
4564
4565 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4566 lcp_open(s, t); // transition to Network phase and send initial IPCP
4567
4568 // Run the plugin's against this new session.
4569 {
4570 struct param_new_session data = { &tunnel[t], &session[s] };
4571 run_plugins(PLUGIN_NEW_SESSION, &data);
4572 }
4573
4574 // Allocate TBFs if throttled
4575 if (session[s].throttle_in || session[s].throttle_out)
4576 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4577
4578 session[s].last_packet = time_now;
4579
4580 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4581 fmtaddr(htonl(session[s].ip), 0),
4582 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4583
4584 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4585
4586 return 1; // RADIUS OK and IP allocated, done...
4587 }
4588
4589 //
4590 // This session just got dropped on us by the master or something.
4591 // Make sure our tables up up to date...
4592 //
4593 int load_session(sessionidt s, sessiont *new)
4594 {
4595 int i;
4596 int newip = 0;
4597
4598 // Sanity checks.
4599 if (new->ip_pool_index >= MAXIPPOOL ||
4600 new->tunnel >= MAXTUNNEL)
4601 {
4602 LOG(0, s, 0, "Strange session update received!\n");
4603 // FIXME! What to do here?
4604 return 0;
4605 }
4606
4607 //
4608 // Ok. All sanity checks passed. Now we're committed to
4609 // loading the new session.
4610 //
4611
4612 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4613
4614 // See if routes/ip cache need updating
4615 if (new->ip != session[s].ip)
4616 newip++;
4617
4618 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4619 if (new->route[i].ip != session[s].route[i].ip ||
4620 new->route[i].mask != session[s].route[i].mask)
4621 newip++;
4622
4623 // needs update
4624 if (newip)
4625 {
4626 int routed = 0;
4627
4628 // remove old routes...
4629 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4630 {
4631 if ((session[s].ip & session[s].route[i].mask) ==
4632 (session[s].route[i].ip & session[s].route[i].mask))
4633 routed++;
4634
4635 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4636 }
4637
4638 // ...ip
4639 if (session[s].ip)
4640 {
4641 if (session[s].ip_pool_index == -1) // static IP
4642 {
4643 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4644 }
4645 else // It's part of the IP pool, remove it manually.
4646 uncache_ipmap(session[s].ip);
4647 }
4648
4649 routed = 0;
4650
4651 // add new routes...
4652 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4653 {
4654 if ((new->ip & new->route[i].mask) ==
4655 (new->route[i].ip & new->route[i].mask))
4656 routed++;
4657
4658 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4659 }
4660
4661 // ...ip
4662 if (new->ip)
4663 {
4664 // If there's a new one, add it.
4665 if (new->ip_pool_index == -1)
4666 {
4667 if (!routed) routeset(s, new->ip, 0, 0, 1);
4668 }
4669 else
4670 cache_ipmap(new->ip, s);
4671 }
4672 }
4673
4674 // check v6 routing
4675 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4676 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4677
4678 // check filters
4679 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4680 {
4681 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4682 new->filter_in = 0;
4683 }
4684
4685 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4686 {
4687 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4688 new->filter_out = 0;
4689 }
4690
4691 if (new->filter_in != session[s].filter_in)
4692 {
4693 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4694 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4695 }
4696
4697 if (new->filter_out != session[s].filter_out)
4698 {
4699 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4700 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4701 }
4702
4703 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4704 // for walking the sessions to forward byte counts to the master.
4705 config->cluster_highest_sessionid = s;
4706
4707 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4708
4709 // Do fixups into address pool.
4710 if (new->ip_pool_index != -1)
4711 fix_address_pool(s);
4712
4713 return 1;
4714 }
4715
4716 static void initplugins()
4717 {
4718 int i;
4719
4720 loaded_plugins = ll_init();
4721 // Initialize the plugins to nothing
4722 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4723 plugins[i] = ll_init();
4724 }
4725
4726 static void *open_plugin(char *plugin_name, int load)
4727 {
4728 char path[256] = "";
4729
4730 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4731 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4732 return dlopen(path, RTLD_NOW);
4733 }
4734
4735 // plugin callback to get a config value
4736 static void *getconfig(char *key, enum config_typet type)
4737 {
4738 int i;
4739
4740 for (i = 0; config_values[i].key; i++)
4741 {
4742 if (!strcmp(config_values[i].key, key))
4743 {
4744 if (config_values[i].type == type)
4745 return ((void *) config) + config_values[i].offset;
4746
4747 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4748 key, type, config_values[i].type);
4749
4750 return 0;
4751 }
4752 }
4753
4754 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4755 return 0;
4756 }
4757
4758 static int add_plugin(char *plugin_name)
4759 {
4760 static struct pluginfuncs funcs = {
4761 _log,
4762 _log_hex,
4763 fmtaddr,
4764 sessionbyuser,
4765 sessiontbysessionidt,
4766 sessionidtbysessiont,
4767 radiusnew,
4768 radiussend,
4769 getconfig,
4770 sessionshutdown,
4771 sessionkill,
4772 throttle_session,
4773 cluster_send_session,
4774 };
4775
4776 void *p = open_plugin(plugin_name, 1);
4777 int (*initfunc)(struct pluginfuncs *);
4778 int i;
4779
4780 if (!p)
4781 {
4782 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4783 return -1;
4784 }
4785
4786 if (ll_contains(loaded_plugins, p))
4787 {
4788 dlclose(p);
4789 return 0; // already loaded
4790 }
4791
4792 {
4793 int *v = dlsym(p, "plugin_api_version");
4794 if (!v || *v != PLUGIN_API_VERSION)
4795 {
4796 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4797 dlclose(p);
4798 return -1;
4799 }
4800 }
4801
4802 if ((initfunc = dlsym(p, "plugin_init")))
4803 {
4804 if (!initfunc(&funcs))
4805 {
4806 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4807 dlclose(p);
4808 return -1;
4809 }
4810 }
4811
4812 ll_push(loaded_plugins, p);
4813
4814 for (i = 0; i < max_plugin_functions; i++)
4815 {
4816 void *x;
4817 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4818 {
4819 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4820 ll_push(plugins[i], x);
4821 }
4822 }
4823
4824 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4825 return 1;
4826 }
4827
4828 static void run_plugin_done(void *plugin)
4829 {
4830 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4831
4832 if (donefunc)
4833 donefunc();
4834 }
4835
4836 static int remove_plugin(char *plugin_name)
4837 {
4838 void *p = open_plugin(plugin_name, 0);
4839 int loaded = 0;
4840
4841 if (!p)
4842 return -1;
4843
4844 if (ll_contains(loaded_plugins, p))
4845 {
4846 int i;
4847 for (i = 0; i < max_plugin_functions; i++)
4848 {
4849 void *x;
4850 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4851 ll_delete(plugins[i], x);
4852 }
4853
4854 ll_delete(loaded_plugins, p);
4855 run_plugin_done(p);
4856 loaded = 1;
4857 }
4858
4859 dlclose(p);
4860 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4861 return loaded;
4862 }
4863
4864 int run_plugins(int plugin_type, void *data)
4865 {
4866 int (*func)(void *data);
4867
4868 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4869 return PLUGIN_RET_ERROR;
4870
4871 ll_reset(plugins[plugin_type]);
4872 while ((func = ll_next(plugins[plugin_type])))
4873 {
4874 int r = func(data);
4875
4876 if (r != PLUGIN_RET_OK)
4877 return r; // stop here
4878 }
4879
4880 return PLUGIN_RET_OK;
4881 }
4882
4883 static void plugins_done()
4884 {
4885 void *p;
4886
4887 ll_reset(loaded_plugins);
4888 while ((p = ll_next(loaded_plugins)))
4889 run_plugin_done(p);
4890 }
4891
4892 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4893 {
4894 struct nsctl request;
4895 struct nsctl response;
4896 int type = unpack_control(&request, buf, len);
4897 int r;
4898 void *p;
4899
4900 if (log_stream && config->debug >= 4)
4901 {
4902 if (type < 0)
4903 {
4904 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4905 fmtaddr(addr->sin_addr.s_addr, 0), type);
4906 }
4907 else
4908 {
4909 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4910 dump_control(&request, log_stream);
4911 }
4912 }
4913
4914 switch (type)
4915 {
4916 case NSCTL_REQ_LOAD:
4917 if (request.argc != 1)
4918 {
4919 response.type = NSCTL_RES_ERR;
4920 response.argc = 1;
4921 response.argv[0] = "name of plugin required";
4922 }
4923 else if ((r = add_plugin(request.argv[0])) < 1)
4924 {
4925 response.type = NSCTL_RES_ERR;
4926 response.argc = 1;
4927 response.argv[0] = !r
4928 ? "plugin already loaded"
4929 : "error loading plugin";
4930 }
4931 else
4932 {
4933 response.type = NSCTL_RES_OK;
4934 response.argc = 0;
4935 }
4936
4937 break;
4938
4939 case NSCTL_REQ_UNLOAD:
4940 if (request.argc != 1)
4941 {
4942 response.type = NSCTL_RES_ERR;
4943 response.argc = 1;
4944 response.argv[0] = "name of plugin required";
4945 }
4946 else if ((r = remove_plugin(request.argv[0])) < 1)
4947 {
4948 response.type = NSCTL_RES_ERR;
4949 response.argc = 1;
4950 response.argv[0] = !r
4951 ? "plugin not loaded"
4952 : "plugin not found";
4953 }
4954 else
4955 {
4956 response.type = NSCTL_RES_OK;
4957 response.argc = 0;
4958 }
4959
4960 break;
4961
4962 case NSCTL_REQ_HELP:
4963 response.type = NSCTL_RES_OK;
4964 response.argc = 0;
4965
4966 ll_reset(loaded_plugins);
4967 while ((p = ll_next(loaded_plugins)))
4968 {
4969 char **help = dlsym(p, "plugin_control_help");
4970 while (response.argc < 0xff && help && *help)
4971 response.argv[response.argc++] = *help++;
4972 }
4973
4974 break;
4975
4976 case NSCTL_REQ_CONTROL:
4977 {
4978 struct param_control param = {
4979 config->cluster_iam_master,
4980 request.argc,
4981 request.argv,
4982 0,
4983 NULL,
4984 };
4985
4986 int r = run_plugins(PLUGIN_CONTROL, &param);
4987
4988 if (r == PLUGIN_RET_ERROR)
4989 {
4990 response.type = NSCTL_RES_ERR;
4991 response.argc = 1;
4992 response.argv[0] = param.additional
4993 ? param.additional
4994 : "error returned by plugin";
4995 }
4996 else if (r == PLUGIN_RET_NOTMASTER)
4997 {
4998 static char msg[] = "must be run on master: 000.000.000.000";
4999
5000 response.type = NSCTL_RES_ERR;
5001 response.argc = 1;
5002 if (config->cluster_master_address)
5003 {
5004 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5005 response.argv[0] = msg;
5006 }
5007 else
5008 {
5009 response.argv[0] = "must be run on master: none elected";
5010 }
5011 }
5012 else if (!(param.response & NSCTL_RESPONSE))
5013 {
5014 response.type = NSCTL_RES_ERR;
5015 response.argc = 1;
5016 response.argv[0] = param.response
5017 ? "unrecognised response value from plugin"
5018 : "unhandled action";
5019 }
5020 else
5021 {
5022 response.type = param.response;
5023 response.argc = 0;
5024 if (param.additional)
5025 {
5026 response.argc = 1;
5027 response.argv[0] = param.additional;
5028 }
5029 }
5030 }
5031
5032 break;
5033
5034 default:
5035 response.type = NSCTL_RES_ERR;
5036 response.argc = 1;
5037 response.argv[0] = "error unpacking control packet";
5038 }
5039
5040 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5041 if (!buf)
5042 {
5043 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5044 return;
5045 }
5046
5047 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5048 if (r > 0)
5049 {
5050 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
5051 if (log_stream && config->debug >= 4)
5052 {
5053 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5054 dump_control(&response, log_stream);
5055 }
5056 }
5057 else
5058 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5059 fmtaddr(addr->sin_addr.s_addr, 0), r);
5060
5061 free(buf);
5062 }
5063
5064 static tunnelidt new_tunnel()
5065 {
5066 tunnelidt i;
5067 for (i = 1; i < MAXTUNNEL; i++)
5068 {
5069 if (tunnel[i].state == TUNNELFREE)
5070 {
5071 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
5072 if (i > config->cluster_highest_tunnelid)
5073 config->cluster_highest_tunnelid = i;
5074 return i;
5075 }
5076 }
5077 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5078 return 0;
5079 }
5080
5081 //
5082 // We're becoming the master. Do any required setup..
5083 //
5084 // This is principally telling all the plugins that we're
5085 // now a master, and telling them about all the sessions
5086 // that are active too..
5087 //
5088 void become_master(void)
5089 {
5090 int s, i;
5091 static struct event_data d[RADIUS_FDS];
5092 struct epoll_event e;
5093
5094 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5095
5096 // running a bunch of iptables commands is slow and can cause
5097 // the master to drop tunnels on takeover--kludge around the
5098 // problem by forking for the moment (note: race)
5099 if (!fork_and_close())
5100 {
5101 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5102 {
5103 if (!session[s].opened) // Not an in-use session.
5104 continue;
5105
5106 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5107 }
5108 exit(0);
5109 }
5110
5111 // add radius fds
5112 e.events = EPOLLIN;
5113 for (i = 0; i < RADIUS_FDS; i++)
5114 {
5115 d[i].type = FD_TYPE_RADIUS;
5116 d[i].index = i;
5117 e.data.ptr = &d[i];
5118
5119 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5120 }
5121 }
5122
5123 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5124 {
5125 int s, i;
5126 int count = 0;
5127 int buckets[64];
5128
5129 if (CLI_HELP_REQUESTED)
5130 return CLI_HELP_NO_ARGS;
5131
5132 time(&time_now);
5133 for (i = 0; i < 64;++i) buckets[i] = 0;
5134
5135 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5136 {
5137 int idle;
5138 if (!session[s].opened)
5139 continue;
5140
5141 idle = time_now - session[s].last_packet;
5142 idle /= 5 ; // In multiples of 5 seconds.
5143 if (idle < 0)
5144 idle = 0;
5145 if (idle > 63)
5146 idle = 63;
5147
5148 ++count;
5149 ++buckets[idle];
5150 }
5151
5152 for (i = 0; i < 63; ++i)
5153 {
5154 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5155 }
5156 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5157 cli_print(cli, "%d total sessions open.", count);
5158 return CLI_OK;
5159 }
5160
5161 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5162 {
5163 int s, i;
5164 int count = 0;
5165 int buckets[64];
5166
5167 if (CLI_HELP_REQUESTED)
5168 return CLI_HELP_NO_ARGS;
5169
5170 time(&time_now);
5171 for (i = 0; i < 64;++i) buckets[i] = 0;
5172
5173 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5174 {
5175 int open = 0, d;
5176 if (!session[s].opened)
5177 continue;
5178
5179 d = time_now - session[s].opened;
5180 if (d < 0)
5181 d = 0;
5182 while (d > 1 && open < 32)
5183 {
5184 ++open;
5185 d >>= 1; // half.
5186 }
5187 ++count;
5188 ++buckets[open];
5189 }
5190
5191 s = 1;
5192 for (i = 0; i < 30; ++i)
5193 {
5194 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5195 s <<= 1;
5196 }
5197 cli_print(cli, "%d total sessions open.", count);
5198 return CLI_OK;
5199 }
5200
5201 /* Unhide an avp.
5202 *
5203 * This unencodes the AVP using the L2TP secret and the previously
5204 * stored random vector. It overwrites the hidden data with the
5205 * unhidden AVP subformat.
5206 */
5207 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5208 {
5209 MD5_CTX ctx;
5210 uint8_t digest[16];
5211 uint8_t *last;
5212 size_t d = 0;
5213 uint16_t m = htons(type);
5214
5215 // Compute initial pad
5216 MD5_Init(&ctx);
5217 MD5_Update(&ctx, (unsigned char *) &m, 2);
5218 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5219 MD5_Update(&ctx, vector, vec_len);
5220 MD5_Final(digest, &ctx);
5221
5222 // pointer to last decoded 16 octets
5223 last = value;
5224
5225 while (len > 0)
5226 {
5227 // calculate a new pad based on the last decoded block
5228 if (d >= sizeof(digest))
5229 {
5230 MD5_Init(&ctx);
5231 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5232 MD5_Update(&ctx, last, sizeof(digest));
5233 MD5_Final(digest, &ctx);
5234
5235 d = 0;
5236 last = value;
5237 }
5238
5239 *value++ ^= digest[d++];
5240 len--;
5241 }
5242 }
5243
5244 int find_filter(char const *name, size_t len)
5245 {
5246 int free = -1;
5247 int i;
5248
5249 for (i = 0; i < MAXFILTER; i++)
5250 {
5251 if (!*ip_filters[i].name)
5252 {
5253 if (free < 0)
5254 free = i;
5255
5256 continue;
5257 }
5258
5259 if (strlen(ip_filters[i].name) != len)
5260 continue;
5261
5262 if (!strncmp(ip_filters[i].name, name, len))
5263 return i;
5264 }
5265
5266 return free;
5267 }
5268
5269 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5270 {
5271 switch (p->op)
5272 {
5273 case FILTER_PORT_OP_EQ: return port == p->port;
5274 case FILTER_PORT_OP_NEQ: return port != p->port;
5275 case FILTER_PORT_OP_GT: return port > p->port;
5276 case FILTER_PORT_OP_LT: return port < p->port;
5277 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5278 }
5279
5280 return 0;
5281 }
5282
5283 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5284 {
5285 switch (op)
5286 {
5287 case FILTER_FLAG_OP_ANY:
5288 return (flags & sflags) || (~flags & cflags);
5289
5290 case FILTER_FLAG_OP_ALL:
5291 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5292
5293 case FILTER_FLAG_OP_EST:
5294 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5295 }
5296
5297 return 0;
5298 }
5299
5300 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5301 {
5302 uint16_t frag_offset;
5303 uint8_t proto;
5304 in_addr_t src_ip;
5305 in_addr_t dst_ip;
5306 uint16_t src_port = 0;
5307 uint16_t dst_port = 0;
5308 uint8_t flags = 0;
5309 ip_filter_rulet *rule;
5310
5311 if (len < 20) // up to end of destination address
5312 return 0;
5313
5314 if ((*buf >> 4) != 4) // IPv4
5315 return 0;
5316
5317 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5318 proto = buf[9];
5319 src_ip = *(in_addr_t *) (buf + 12);
5320 dst_ip = *(in_addr_t *) (buf + 16);
5321
5322 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5323 {
5324 int l = (buf[0] & 0xf) * 4; // length of IP header
5325 if (len < l + 4) // ports
5326 return 0;
5327
5328 src_port = ntohs(*(uint16_t *) (buf + l));
5329 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5330 if (proto == IPPROTO_TCP)
5331 {
5332 if (len < l + 14) // flags
5333 return 0;
5334
5335 flags = buf[l + 13] & 0x3f;
5336 }
5337 }
5338
5339 for (rule = ip_filters[filter].rules; rule->action; rule++)
5340 {
5341 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5342 continue;
5343
5344 if (rule->src_wild != INADDR_BROADCAST &&
5345 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5346 continue;
5347
5348 if (rule->dst_wild != INADDR_BROADCAST &&
5349 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5350 continue;
5351
5352 if (frag_offset)
5353 {
5354 // layer 4 deny rules are skipped
5355 if (rule->action == FILTER_ACTION_DENY &&
5356 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
5357 continue;
5358 }
5359 else
5360 {
5361 if (rule->frag)
5362 continue;
5363
5364 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5365 {
5366 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5367 continue;
5368
5369 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5370 continue;
5371
5372 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5373 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5374 continue;
5375 }
5376 }
5377
5378 // matched
5379 rule->counter++;
5380 return rule->action == FILTER_ACTION_PERMIT;
5381 }
5382
5383 // default deny
5384 return 0;
5385 }