8f1ace5b921f9dfc17cd748d5421007886fbfd4e
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005, 2006 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 #include <arpa/inet.h>
8 #include <assert.h>
9 #include <errno.h>
10 #include <fcntl.h>
11 #include <linux/if_tun.h>
12 #define SYSLOG_NAMES
13 #include <syslog.h>
14 #include <malloc.h>
15 #include <net/route.h>
16 #include <sys/mman.h>
17 #include <netdb.h>
18 #include <netinet/in.h>
19 #include <netinet/ip6.h>
20 #include <stdarg.h>
21 #include <stdlib.h>
22 #include <stdio.h>
23 #include <string.h>
24 #include <ctype.h>
25 #include <sys/ioctl.h>
26 #include <sys/socket.h>
27 #include <sys/stat.h>
28 #include <sys/time.h>
29 #include <sys/resource.h>
30 #include <sys/wait.h>
31 #include <net/if.h>
32 #include <stddef.h>
33 #include <time.h>
34 #include <dlfcn.h>
35 #include <unistd.h>
36 #include <sched.h>
37 #include <sys/sysinfo.h>
38 #include <libcli.h>
39 #include <linux/netlink.h>
40 #include <linux/rtnetlink.h>
41
42 #include "md5.h"
43 #include "l2tpns.h"
44 #include "cluster.h"
45 #include "plugin.h"
46 #include "ll.h"
47 #include "constants.h"
48 #include "control.h"
49 #include "util.h"
50 #include "tbf.h"
51
52 #ifdef BGP
53 #include "bgp.h"
54 #endif
55
56 #include "l2tplac.h"
57 #include "pppoe.h"
58
59 char * Vendor_name = "Linux L2TPNS";
60 uint32_t call_serial_number = 0;
61
62 // Globals
63 configt *config = NULL; // all configuration
64 int nlfd = -1; // netlink socket
65 int tunfd = -1; // tun interface file handle. (network device)
66 int udpfd[MAX_UDPFD + 1] = INIT_TABUDPFD; // array UDP file handle + 1 for lac udp
67 int udplacfd = -1; // UDP LAC file handle
68 int controlfd = -1; // Control signal handle
69 int clifd = -1; // Socket listening for CLI connections.
70 int daefd = -1; // Socket listening for DAE connections.
71 int snoopfd = -1; // UDP file handle for sending out intercept data
72 int *radfds = NULL; // RADIUS requests file handles
73 int rand_fd = -1; // Random data source
74 int cluster_sockfd = -1; // Intra-cluster communications socket.
75 int epollfd = -1; // event polling
76 time_t basetime = 0; // base clock
77 char hostname[MAXHOSTNAME] = ""; // us.
78 static int tunidx; // ifr_ifindex of tun device
79 int nlseqnum = 0; // netlink sequence number
80 int min_initok_nlseqnum = 0; // minimun seq number for messages after init is ok
81 static int syslog_log = 0; // are we logging to syslog
82 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
83 uint32_t last_id = 0; // Unique ID for radius accounting
84 // Guest change
85 char guest_users[10][32]; // Array of guest users
86 int guest_accounts_num = 0; // Number of guest users
87
88 // calculated from config->l2tp_mtu
89 uint16_t MRU = 0; // PPP MRU
90 uint16_t MSS = 0; // TCP MSS
91
92 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
93 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
94
95 union iphash {
96 sessionidt sess;
97 union iphash *idx;
98 } ip_hash[256]; // Mapping from IP address to session structures.
99
100 struct ipv6radix {
101 sessionidt sess;
102 struct ipv6radix *branch;
103 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
104
105 // Traffic counters.
106 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
107 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
108 uint32_t eth_tx = 0;
109
110 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
111 time_t time_now = 0; // Current time in seconds since epoch.
112 uint64_t time_now_ms = 0; // Current time in milliseconds since epoch.
113 static char time_now_string[64] = {0}; // Current time as a string.
114 static int time_changed = 0; // time_now changed
115 char main_quit = 0; // True if we're in the process of exiting.
116 static char main_reload = 0; // Re-load pending
117 linked_list *loaded_plugins;
118 linked_list *plugins[MAX_PLUGIN_TYPES];
119
120 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
121 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
122
123 config_descriptt config_values[] = {
124 CONFIG("debug", debug, INT),
125 CONFIG("log_file", log_filename, STRING),
126 CONFIG("pid_file", pid_file, STRING),
127 CONFIG("random_device", random_device, STRING),
128 CONFIG("l2tp_secret", l2tp_secret, STRING),
129 CONFIG("l2tp_mtu", l2tp_mtu, INT),
130 CONFIG("ppp_restart_time", ppp_restart_time, INT),
131 CONFIG("ppp_max_configure", ppp_max_configure, INT),
132 CONFIG("ppp_max_failure", ppp_max_failure, INT),
133 CONFIG("primary_dns", default_dns1, IPv4),
134 CONFIG("secondary_dns", default_dns2, IPv4),
135 CONFIG("primary_radius", radiusserver[0], IPv4),
136 CONFIG("secondary_radius", radiusserver[1], IPv4),
137 CONFIG("primary_radius_port", radiusport[0], SHORT),
138 CONFIG("secondary_radius_port", radiusport[1], SHORT),
139 CONFIG("radius_accounting", radius_accounting, BOOL),
140 CONFIG("radius_interim", radius_interim, INT),
141 CONFIG("radius_secret", radiussecret, STRING),
142 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
143 CONFIG("radius_dae_port", radius_dae_port, SHORT),
144 CONFIG("radius_bind_min", radius_bind_min, SHORT),
145 CONFIG("radius_bind_max", radius_bind_max, SHORT),
146 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
147 CONFIG("kill_timedout_sessions", kill_timedout_sessions, BOOL),
148 CONFIG("guest_account", guest_user, STRING),
149 CONFIG("bind_address", bind_address, IPv4),
150 CONFIG("peer_address", peer_address, IPv4),
151 CONFIG("send_garp", send_garp, BOOL),
152 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
153 CONFIG("throttle_buckets", num_tbfs, INT),
154 CONFIG("accounting_dir", accounting_dir, STRING),
155 CONFIG("dump_speed", dump_speed, BOOL),
156 CONFIG("multi_read_count", multi_read_count, INT),
157 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
158 CONFIG("lock_pages", lock_pages, BOOL),
159 CONFIG("icmp_rate", icmp_rate, INT),
160 CONFIG("packet_limit", max_packets, INT),
161 CONFIG("cluster_address", cluster_address, IPv4),
162 CONFIG("cluster_interface", cluster_interface, STRING),
163 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
164 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
165 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
166 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
167 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
168 CONFIG("cli_bind_address", cli_bind_address, IPv4),
169 CONFIG("hostname", hostname, STRING),
170 #ifdef BGP
171 CONFIG("nexthop_address", nexthop_address, IPv4),
172 CONFIG("nexthop6_address", nexthop6_address, IPv6),
173 #endif
174 CONFIG("echo_timeout", echo_timeout, INT),
175 CONFIG("idle_echo_timeout", idle_echo_timeout, INT),
176 CONFIG("iftun_address", iftun_address, IPv4),
177 CONFIG("tundevicename", tundevicename, STRING),
178 CONFIG("disable_lac_func", disable_lac_func, BOOL),
179 CONFIG("auth_tunnel_change_addr_src", auth_tunnel_change_addr_src, BOOL),
180 CONFIG("bind_address_remotelns", bind_address_remotelns, IPv4),
181 CONFIG("bind_portremotelns", bind_portremotelns, SHORT),
182 CONFIG("pppoe_if_to_bind", pppoe_if_to_bind, STRING),
183 CONFIG("pppoe_service_name", pppoe_service_name, STRING),
184 CONFIG("pppoe_ac_name", pppoe_ac_name, STRING),
185 CONFIG("disable_sending_hello", disable_sending_hello, BOOL),
186 CONFIG("disable_no_spoof", disable_no_spoof, BOOL),
187 CONFIG("bind_multi_address", bind_multi_address, STRING),
188 CONFIG("pppoe_only_equal_svc_name", pppoe_only_equal_svc_name, BOOL),
189 { NULL, 0, 0, 0 }
190 };
191
192 static char *plugin_functions[] = {
193 NULL,
194 "plugin_pre_auth",
195 "plugin_post_auth",
196 "plugin_timer",
197 "plugin_new_session",
198 "plugin_kill_session",
199 "plugin_control",
200 "plugin_radius_response",
201 "plugin_radius_reset",
202 "plugin_radius_account",
203 "plugin_become_master",
204 "plugin_new_session_master",
205 };
206
207 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
208
209 // Counters for shutdown sessions
210 static sessiont shut_acct[8192];
211 static sessionidt shut_acct_n = 0;
212
213 tunnelt *tunnel = NULL; // Array of tunnel structures.
214 bundlet *bundle = NULL; // Array of bundle structures.
215 fragmentationt *frag = NULL; // Array of fragmentation structures.
216 sessiont *session = NULL; // Array of session structures.
217 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
218 radiust *radius = NULL; // Array of radius structures.
219 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
220 ip_filtert *ip_filters = NULL; // Array of named filters.
221 static controlt *controlfree = 0;
222 struct Tstats *_statistics = NULL;
223 #ifdef RINGBUFFER
224 struct Tringbuffer *ringbuffer = NULL;
225 #endif
226
227 static ssize_t netlink_send(struct nlmsghdr *nh);
228 static void netlink_addattr(struct nlmsghdr *nh, int type, const void *data, int alen);
229 static void cache_ipmap(in_addr_t ip, sessionidt s);
230 static void uncache_ipmap(in_addr_t ip);
231 static void cache_ipv6map(struct in6_addr ip, int prefixlen, sessionidt s);
232 static void free_ip_address(sessionidt s);
233 static void dump_acct_info(int all);
234 static void sighup_handler(int sig);
235 static void shutdown_handler(int sig);
236 static void sigchild_handler(int sig);
237 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
238 static void update_config(void);
239 static void read_config_file(void);
240 static void initplugins(void);
241 static int add_plugin(char *plugin_name);
242 static int remove_plugin(char *plugin_name);
243 static void plugins_done(void);
244 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
245 static tunnelidt new_tunnel(void);
246 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
247 static void bundleclear(bundleidt b);
248
249 // return internal time (10ths since process startup), set f if given
250 // as a side-effect sets time_now, and time_changed
251 static clockt now(double *f)
252 {
253 struct timeval t;
254 gettimeofday(&t, 0);
255 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
256 if (t.tv_sec != time_now)
257 {
258 time_now = t.tv_sec;
259 time_changed++;
260 }
261
262 // Time in milliseconds
263 // TODO FOR MLPPP DEV
264 //time_now_ms = (t.tv_sec * 1000) + (t.tv_usec/1000);
265
266 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
267 }
268
269 // work out a retry time based on try number
270 // This is a straight bounded exponential backoff.
271 // Maximum re-try time is 32 seconds. (2^5).
272 clockt backoff(uint8_t try)
273 {
274 if (try > 5) try = 5; // max backoff
275 return now(NULL) + 10 * (1 << try);
276 }
277
278
279 //
280 // Log a debug message. Typically called via the LOG macro
281 //
282 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
283 {
284 static char message[65536] = {0};
285 va_list ap;
286
287 #ifdef RINGBUFFER
288 if (ringbuffer)
289 {
290 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
291 ringbuffer->tail = 0;
292 if (ringbuffer->tail == ringbuffer->head)
293 if (++ringbuffer->head >= RINGBUFFER_SIZE)
294 ringbuffer->head = 0;
295
296 ringbuffer->buffer[ringbuffer->tail].level = level;
297 ringbuffer->buffer[ringbuffer->tail].session = s;
298 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
299 va_start(ap, format);
300 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, MAX_LOG_LENGTH, format, ap);
301 va_end(ap);
302 }
303 #endif
304
305 if (config->debug < level) return;
306
307 va_start(ap, format);
308 vsnprintf(message, sizeof(message), format, ap);
309
310 if (log_stream)
311 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
312 else if (syslog_log)
313 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
314
315 va_end(ap);
316 }
317
318 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
319 {
320 int i, j;
321 const uint8_t *d = data;
322
323 if (config->debug < level) return;
324
325 // No support for _log_hex to syslog
326 if (log_stream)
327 {
328 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
329 setvbuf(log_stream, NULL, _IOFBF, 16384);
330
331 for (i = 0; i < maxsize; )
332 {
333 fprintf(log_stream, "%4X: ", i);
334 for (j = i; j < maxsize && j < (i + 16); j++)
335 {
336 fprintf(log_stream, "%02X ", d[j]);
337 if (j == i + 7)
338 fputs(": ", log_stream);
339 }
340
341 for (; j < i + 16; j++)
342 {
343 fputs(" ", log_stream);
344 if (j == i + 7)
345 fputs(": ", log_stream);
346 }
347
348 fputs(" ", log_stream);
349 for (j = i; j < maxsize && j < (i + 16); j++)
350 {
351 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
352 fputc(d[j], log_stream);
353 else
354 fputc('.', log_stream);
355
356 if (j == i + 7)
357 fputs(" ", log_stream);
358 }
359
360 i = j;
361 fputs("\n", log_stream);
362 }
363
364 fflush(log_stream);
365 setbuf(log_stream, NULL);
366 }
367 }
368
369 // update a counter, accumulating 2^32 wraps
370 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
371 {
372 uint32_t new = *counter + delta;
373 if (new < *counter)
374 (*wrap)++;
375
376 *counter = new;
377 }
378
379 // initialise the random generator
380 static void initrandom(char *source)
381 {
382 static char path[sizeof(config->random_device)] = "*undefined*";
383
384 // reinitialise only if we are forced to do so or if the config has changed
385 if (source && !strncmp(path, source, sizeof(path)))
386 return;
387
388 // close previous source, if any
389 if (rand_fd >= 0)
390 close(rand_fd);
391
392 rand_fd = -1;
393
394 if (source)
395 {
396 // register changes
397 snprintf(path, sizeof(path), "%s", source);
398
399 if (*path == '/')
400 {
401 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
402 if (rand_fd < 0)
403 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
404 path, strerror(errno));
405 }
406 }
407 }
408
409 // fill buffer with random data
410 void random_data(uint8_t *buf, int len)
411 {
412 int n = 0;
413
414 CSTAT(random_data);
415 if (rand_fd >= 0)
416 {
417 n = read(rand_fd, buf, len);
418 if (n >= len) return;
419 if (n < 0)
420 {
421 if (errno != EAGAIN)
422 {
423 LOG(0, 0, 0, "Error reading from random source: %s\n",
424 strerror(errno));
425
426 // fall back to rand()
427 initrandom(NULL);
428 }
429
430 n = 0;
431 }
432 }
433
434 // append missing data
435 while (n < len)
436 // not using the low order bits from the prng stream
437 buf[n++] = (rand() >> 4) & 0xff;
438 }
439
440 // Add a route
441 //
442 // This adds it to the routing table, advertises it
443 // via BGP if enabled, and stuffs it into the
444 // 'sessionbyip' cache.
445 //
446 // 'ip' must be in _host_ order.
447 //
448 static void routeset(sessionidt s, in_addr_t ip, int prefixlen, in_addr_t gw, int add)
449 {
450 struct {
451 struct nlmsghdr nh;
452 struct rtmsg rt;
453 char buf[32];
454 } req;
455 int i;
456 in_addr_t n_ip;
457
458 if (!prefixlen) prefixlen = 32;
459
460 ip &= 0xffffffff << (32 - prefixlen);; // Force the ip to be the first one in the route.
461
462 memset(&req, 0, sizeof(req));
463
464 if (add)
465 {
466 req.nh.nlmsg_type = RTM_NEWROUTE;
467 req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE;
468 }
469 else
470 {
471 req.nh.nlmsg_type = RTM_DELROUTE;
472 req.nh.nlmsg_flags = NLM_F_REQUEST;
473 }
474
475 req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.rt));
476
477 req.rt.rtm_family = AF_INET;
478 req.rt.rtm_dst_len = prefixlen;
479 req.rt.rtm_table = RT_TABLE_MAIN;
480 req.rt.rtm_protocol = 42;
481 req.rt.rtm_scope = RT_SCOPE_LINK;
482 req.rt.rtm_type = RTN_UNICAST;
483
484 netlink_addattr(&req.nh, RTA_OIF, &tunidx, sizeof(int));
485 n_ip = htonl(ip);
486 netlink_addattr(&req.nh, RTA_DST, &n_ip, sizeof(n_ip));
487 if (gw)
488 {
489 n_ip = htonl(gw);
490 netlink_addattr(&req.nh, RTA_GATEWAY, &n_ip, sizeof(n_ip));
491 }
492
493 LOG(1, s, session[s].tunnel, "Route %s %s/%d%s%s\n", add ? "add" : "del",
494 fmtaddr(htonl(ip), 0), prefixlen,
495 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
496
497 if (netlink_send(&req.nh) < 0)
498 LOG(0, 0, 0, "routeset() error in sending netlink message: %s\n", strerror(errno));
499
500 #ifdef BGP
501 if (add)
502 bgp_add_route(htonl(ip), prefixlen);
503 else
504 bgp_del_route(htonl(ip), prefixlen);
505 #endif /* BGP */
506
507 // Add/Remove the IPs to the 'sessionbyip' cache.
508 // Note that we add the zero address in the case of
509 // a network route. Roll on CIDR.
510
511 // Note that 's == 0' implies this is the address pool.
512 // We still cache it here, because it will pre-fill
513 // the malloc'ed tree.
514
515 if (s)
516 {
517 if (!add) // Are we deleting a route?
518 s = 0; // Caching the session as '0' is the same as uncaching.
519
520 for (i = ip; i < ip+(1<<(32-prefixlen)) ; ++i)
521 cache_ipmap(i, s);
522 }
523 }
524
525 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
526 {
527 struct {
528 struct nlmsghdr nh;
529 struct rtmsg rt;
530 char buf[64];
531 } req;
532 int metric;
533 char ipv6addr[INET6_ADDRSTRLEN];
534
535 if (!config->ipv6_prefix.s6_addr[0])
536 {
537 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
538 return;
539 }
540
541 memset(&req, 0, sizeof(req));
542
543 if (add)
544 {
545 req.nh.nlmsg_type = RTM_NEWROUTE;
546 req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE;
547 }
548 else
549 {
550 req.nh.nlmsg_type = RTM_DELROUTE;
551 req.nh.nlmsg_flags = NLM_F_REQUEST;
552 }
553
554 req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.rt));
555
556 req.rt.rtm_family = AF_INET6;
557 req.rt.rtm_dst_len = prefixlen;
558 req.rt.rtm_table = RT_TABLE_MAIN;
559 req.rt.rtm_protocol = 42;
560 req.rt.rtm_scope = RT_SCOPE_LINK;
561 req.rt.rtm_type = RTN_UNICAST;
562
563 netlink_addattr(&req.nh, RTA_OIF, &tunidx, sizeof(int));
564 netlink_addattr(&req.nh, RTA_DST, &ip, sizeof(ip));
565 metric = 1;
566 netlink_addattr(&req.nh, RTA_METRICS, &metric, sizeof(metric));
567
568 LOG(1, s, session[s].tunnel, "Route %s %s/%d\n",
569 add ? "add" : "del",
570 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
571 prefixlen);
572
573 if (netlink_send(&req.nh) < 0)
574 LOG(0, 0, 0, "route6set() error in sending netlink message: %s\n", strerror(errno));
575
576 #ifdef BGP
577 if (add)
578 bgp_add_route6(ip, prefixlen);
579 else
580 bgp_del_route6(ip, prefixlen);
581 #endif /* BGP */
582
583 if (s)
584 {
585 if (!add) // Are we deleting a route?
586 s = 0; // Caching the session as '0' is the same as uncaching.
587
588 cache_ipv6map(ip, prefixlen, s);
589 }
590
591 return;
592 }
593
594 //
595 // Set up netlink socket
596 static void initnetlink(void)
597 {
598 struct sockaddr_nl nladdr;
599
600 nlfd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
601 if (nlfd < 0)
602 {
603 LOG(0, 0, 0, "Can't create netlink socket: %s\n", strerror(errno));
604 exit(1);
605 }
606
607 memset(&nladdr, 0, sizeof(nladdr));
608 nladdr.nl_family = AF_NETLINK;
609 nladdr.nl_pid = getpid();
610
611 if (bind(nlfd, (struct sockaddr *)&nladdr, sizeof(nladdr)) < 0)
612 {
613 LOG(0, 0, 0, "Can't bind netlink socket: %s\n", strerror(errno));
614 exit(1);
615 }
616 }
617
618 static ssize_t netlink_send(struct nlmsghdr *nh)
619 {
620 struct sockaddr_nl nladdr;
621 struct iovec iov;
622 struct msghdr msg;
623
624 nh->nlmsg_pid = getpid();
625 nh->nlmsg_seq = ++nlseqnum;
626
627 // set kernel address
628 memset(&nladdr, 0, sizeof(nladdr));
629 nladdr.nl_family = AF_NETLINK;
630
631 iov = (struct iovec){ (void *)nh, nh->nlmsg_len };
632 msg = (struct msghdr){ (void *)&nladdr, sizeof(nladdr), &iov, 1, NULL, 0, 0 };
633
634 return sendmsg(nlfd, &msg, 0);
635 }
636
637 static ssize_t netlink_recv(void *buf, ssize_t len)
638 {
639 struct sockaddr_nl nladdr;
640 struct iovec iov;
641 struct msghdr msg;
642
643 // set kernel address
644 memset(&nladdr, 0, sizeof(nladdr));
645 nladdr.nl_family = AF_NETLINK;
646
647 iov = (struct iovec){ buf, len };
648 msg = (struct msghdr){ (void *)&nladdr, sizeof(nladdr), &iov, 1, NULL, 0, 0 };
649
650 return recvmsg(nlfd, &msg, 0);
651 }
652
653 /* adapted from iproute2 */
654 static void netlink_addattr(struct nlmsghdr *nh, int type, const void *data, int alen)
655 {
656 int len = RTA_LENGTH(alen);
657 struct rtattr *rta;
658
659 rta = (struct rtattr *)(((void *)nh) + NLMSG_ALIGN(nh->nlmsg_len));
660 rta->rta_type = type;
661 rta->rta_len = len;
662 memcpy(RTA_DATA(rta), data, alen);
663 nh->nlmsg_len = NLMSG_ALIGN(nh->nlmsg_len) + RTA_ALIGN(len);
664 }
665
666 // messages corresponding to different phases seq number
667 static char *tun_nl_phase_msg[] = {
668 "initialized",
669 "getting tun interface index",
670 "setting tun interface parameters",
671 "setting tun IPv4 address",
672 "setting tun LL IPv6 address",
673 "setting tun global IPv6 address",
674 };
675
676 //
677 // Set up TUN interface
678 static void inittun(void)
679 {
680 struct ifreq ifr;
681
682 memset(&ifr, 0, sizeof(ifr));
683 ifr.ifr_flags = IFF_TUN;
684
685 tunfd = open(TUNDEVICE, O_RDWR);
686 if (tunfd < 0)
687 { // fatal
688 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
689 exit(1);
690 }
691 {
692 int flags = fcntl(tunfd, F_GETFL, 0);
693 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
694 }
695
696 if (*config->tundevicename)
697 strncpy(ifr.ifr_name, config->tundevicename, IFNAMSIZ);
698
699 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
700 {
701 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
702 exit(1);
703 }
704 assert(strlen(ifr.ifr_name) < sizeof(config->tundevicename) - 1);
705 strncpy(config->tundevicename, ifr.ifr_name, sizeof(config->tundevicename));
706
707 tunidx = if_nametoindex(config->tundevicename);
708 if (tunidx == 0)
709 {
710 LOG(0, 0, 0, "Can't get tun interface index\n");
711 exit(1);
712 }
713
714 {
715 struct {
716 // interface setting
717 struct nlmsghdr nh;
718 union {
719 struct ifinfomsg ifinfo;
720 struct ifaddrmsg ifaddr;
721 } ifmsg;
722 char rtdata[32]; // 32 should be enough
723 } req;
724 uint32_t txqlen, mtu;
725 in_addr_t ip;
726
727 memset(&req, 0, sizeof(req));
728
729 req.nh.nlmsg_type = RTM_NEWLINK;
730 req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_MULTI;
731 req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifinfo));
732
733 req.ifmsg.ifinfo.ifi_family = AF_UNSPEC;
734 req.ifmsg.ifinfo.ifi_index = tunidx;
735 req.ifmsg.ifinfo.ifi_flags |= IFF_UP; // set interface up
736 req.ifmsg.ifinfo.ifi_change = IFF_UP; // only change this flag
737
738 /* Bump up the qlen to deal with bursts from the network */
739 txqlen = 1000;
740 netlink_addattr(&req.nh, IFLA_TXQLEN, &txqlen, sizeof(txqlen));
741 /* set MTU to modem MRU */
742 mtu = MRU;
743 netlink_addattr(&req.nh, IFLA_MTU, &mtu, sizeof(mtu));
744
745 if (netlink_send(&req.nh) < 0)
746 goto senderror;
747
748 memset(&req, 0, sizeof(req));
749
750 req.nh.nlmsg_type = RTM_NEWADDR;
751 req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_MULTI;
752 req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr));
753
754 req.ifmsg.ifaddr.ifa_family = AF_INET;
755 req.ifmsg.ifaddr.ifa_prefixlen = 32;
756 req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_UNIVERSE;
757 req.ifmsg.ifaddr.ifa_index = tunidx;
758
759 if (config->nbmultiaddress > 1)
760 {
761 int i;
762 for (i = 0; i < config->nbmultiaddress ; i++)
763 {
764 ip = config->iftun_n_address[i];
765 netlink_addattr(&req.nh, IFA_LOCAL, &ip, sizeof(ip));
766 if (netlink_send(&req.nh) < 0)
767 goto senderror;
768 }
769 }
770 else
771 {
772 if (config->iftun_address)
773 ip = config->iftun_address;
774 else
775 ip = 0x01010101; // 1.1.1.1
776 netlink_addattr(&req.nh, IFA_LOCAL, &ip, sizeof(ip));
777
778 if (netlink_send(&req.nh) < 0)
779 goto senderror;
780 }
781
782
783
784 // Only setup IPv6 on the tun device if we have a configured prefix
785 if (config->ipv6_prefix.s6_addr[0]) {
786 struct in6_addr ip6;
787
788 memset(&req, 0, sizeof(req));
789
790 req.nh.nlmsg_type = RTM_NEWADDR;
791 req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_MULTI;
792 req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr));
793
794 req.ifmsg.ifaddr.ifa_family = AF_INET6;
795 req.ifmsg.ifaddr.ifa_prefixlen = 64;
796 req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_LINK;
797 req.ifmsg.ifaddr.ifa_index = tunidx;
798
799 // Link local address is FE80::1
800 memset(&ip6, 0, sizeof(ip6));
801 ip6.s6_addr[0] = 0xFE;
802 ip6.s6_addr[1] = 0x80;
803 ip6.s6_addr[15] = 1;
804 netlink_addattr(&req.nh, IFA_LOCAL, &ip6, sizeof(ip6));
805
806 if (netlink_send(&req.nh) < 0)
807 goto senderror;
808
809 memset(&req, 0, sizeof(req));
810
811 req.nh.nlmsg_type = RTM_NEWADDR;
812 req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE | NLM_F_MULTI;
813 req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr));
814
815 req.ifmsg.ifaddr.ifa_family = AF_INET6;
816 req.ifmsg.ifaddr.ifa_prefixlen = 64;
817 req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_UNIVERSE;
818 req.ifmsg.ifaddr.ifa_index = tunidx;
819
820 // Global address is prefix::1
821 ip6 = config->ipv6_prefix;
822 ip6.s6_addr[15] = 1;
823 netlink_addattr(&req.nh, IFA_LOCAL, &ip6, sizeof(ip6));
824
825 if (netlink_send(&req.nh) < 0)
826 goto senderror;
827 }
828
829 memset(&req, 0, sizeof(req));
830
831 req.nh.nlmsg_type = NLMSG_DONE;
832 req.nh.nlmsg_len = NLMSG_LENGTH(0);
833
834 if (netlink_send(&req.nh) < 0)
835 goto senderror;
836
837 // if we get an error for seqnum < min_initok_nlseqnum,
838 // we must exit as initialization went wrong
839 if (config->ipv6_prefix.s6_addr[0])
840 min_initok_nlseqnum = 5 + 1; // idx + if + addr + 2*addr6
841 else
842 min_initok_nlseqnum = 3 + 1; // idx + if + addr
843 }
844
845 return;
846
847 senderror:
848 LOG(0, 0, 0, "Error while setting up tun device: %s\n", strerror(errno));
849 exit(1);
850 }
851
852 // set up LAC UDP ports
853 static void initlacudp(void)
854 {
855 int on = 1;
856 struct sockaddr_in addr;
857
858 // Tunnel to Remote LNS
859 memset(&addr, 0, sizeof(addr));
860 addr.sin_family = AF_INET;
861 addr.sin_port = htons(config->bind_portremotelns);
862 addr.sin_addr.s_addr = config->bind_address_remotelns;
863 udplacfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
864 setsockopt(udplacfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
865 {
866 int flags = fcntl(udplacfd, F_GETFL, 0);
867 fcntl(udplacfd, F_SETFL, flags | O_NONBLOCK);
868 }
869 if (bind(udplacfd, (struct sockaddr *) &addr, sizeof(addr)) < 0)
870 {
871 LOG(0, 0, 0, "Error in UDP REMOTE LNS bind: %s\n", strerror(errno));
872 exit(1);
873 }
874 }
875
876 // set up control ports
877 static void initcontrol(void)
878 {
879 int on = 1;
880 struct sockaddr_in addr;
881
882 // Control
883 memset(&addr, 0, sizeof(addr));
884 addr.sin_family = AF_INET;
885 addr.sin_port = htons(NSCTL_PORT);
886 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
887 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
888 setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
889 if (bind(controlfd, (struct sockaddr *) &addr, sizeof(addr)) < 0)
890 {
891 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
892 exit(1);
893 }
894 }
895
896 // set up Dynamic Authorization Extensions to RADIUS port
897 static void initdae(void)
898 {
899 int on = 1;
900 struct sockaddr_in addr;
901
902 // Dynamic Authorization Extensions to RADIUS
903 memset(&addr, 0, sizeof(addr));
904 addr.sin_family = AF_INET;
905 addr.sin_port = htons(config->radius_dae_port);
906 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
907 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
908 setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
909 if (bind(daefd, (struct sockaddr *) &addr, sizeof(addr)) < 0)
910 {
911 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
912 exit(1);
913 }
914 }
915
916 // set up UDP ports
917 static void initudp(int * pudpfd, in_addr_t ip_bind)
918 {
919 int on = 1;
920 struct sockaddr_in addr;
921
922 // Tunnel
923 memset(&addr, 0, sizeof(addr));
924 addr.sin_family = AF_INET;
925 addr.sin_port = htons(L2TPPORT);
926 addr.sin_addr.s_addr = ip_bind;
927 (*pudpfd) = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
928 setsockopt((*pudpfd), SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
929 {
930 int flags = fcntl((*pudpfd), F_GETFL, 0);
931 fcntl((*pudpfd), F_SETFL, flags | O_NONBLOCK);
932 }
933 if (bind((*pudpfd), (struct sockaddr *) &addr, sizeof(addr)) < 0)
934 {
935 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
936 exit(1);
937 }
938 }
939
940 //
941 // Find session by IP, < 1 for not found
942 //
943 // Confusingly enough, this 'ip' must be
944 // in _network_ order. This being the common
945 // case when looking it up from IP packet headers.
946 //
947 // We actually use this cache for two things.
948 // #1. For used IP addresses, this maps to the
949 // session ID that it's used by.
950 // #2. For un-used IP addresses, this maps to the
951 // index into the pool table that contains that
952 // IP address.
953 //
954
955 static sessionidt lookup_ipmap(in_addr_t ip)
956 {
957 uint8_t *a = (uint8_t *) &ip;
958 union iphash *h = ip_hash;
959
960 if (!(h = h[*a++].idx)) return 0;
961 if (!(h = h[*a++].idx)) return 0;
962 if (!(h = h[*a++].idx)) return 0;
963
964 return h[*a].sess;
965 }
966
967 static sessionidt lookup_ipv6map(struct in6_addr ip)
968 {
969 struct ipv6radix *curnode;
970 int i;
971 int s;
972 char ipv6addr[INET6_ADDRSTRLEN];
973
974 curnode = &ipv6_hash[ip.s6_addr[0]];
975 i = 1;
976 s = curnode->sess;
977
978 while (s == 0 && i < 15 && curnode->branch != NULL)
979 {
980 curnode = &curnode->branch[ip.s6_addr[i]];
981 s = curnode->sess;
982 i++;
983 }
984
985 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
986 inet_ntop(AF_INET6, &ip, ipv6addr,
987 INET6_ADDRSTRLEN),
988 s);
989
990 return s;
991 }
992
993 sessionidt sessionbyip(in_addr_t ip)
994 {
995 sessionidt s = lookup_ipmap(ip);
996 CSTAT(sessionbyip);
997
998 if (s > 0 && s < MAXSESSION && session[s].opened)
999 return s;
1000
1001 return 0;
1002 }
1003
1004 sessionidt sessionbyipv6(struct in6_addr ip)
1005 {
1006 sessionidt s;
1007 CSTAT(sessionbyipv6);
1008
1009 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
1010 (ip.s6_addr[0] == 0xFE &&
1011 ip.s6_addr[1] == 0x80 &&
1012 ip.s6_addr16[1] == 0 &&
1013 ip.s6_addr16[2] == 0 &&
1014 ip.s6_addr16[3] == 0)) {
1015 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
1016 } else {
1017 s = lookup_ipv6map(ip);
1018 }
1019
1020 if (s > 0 && s < MAXSESSION && session[s].opened)
1021 return s;
1022
1023 return 0;
1024 }
1025
1026 //
1027 // Take an IP address in HOST byte order and
1028 // add it to the sessionid by IP cache.
1029 //
1030 // (It's actually cached in network order)
1031 //
1032 static void cache_ipmap(in_addr_t ip, sessionidt s)
1033 {
1034 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
1035 uint8_t *a = (uint8_t *) &nip;
1036 union iphash *h = ip_hash;
1037 int i;
1038
1039 for (i = 0; i < 3; i++)
1040 {
1041 if (!(h[a[i]].idx || (h[a[i]].idx = calloc(256, sizeof(union iphash)))))
1042 return;
1043
1044 h = h[a[i]].idx;
1045 }
1046
1047 h[a[3]].sess = s;
1048
1049 if (s > 0)
1050 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
1051
1052 else if (s == 0)
1053 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
1054 // else a map to an ip pool index.
1055 }
1056
1057 static void uncache_ipmap(in_addr_t ip)
1058 {
1059 cache_ipmap(ip, 0); // Assign it to the NULL session.
1060 }
1061
1062 static void cache_ipv6map(struct in6_addr ip, int prefixlen, sessionidt s)
1063 {
1064 int i;
1065 int bytes;
1066 struct ipv6radix *curnode;
1067 char ipv6addr[INET6_ADDRSTRLEN];
1068
1069 curnode = &ipv6_hash[ip.s6_addr[0]];
1070
1071 bytes = prefixlen >> 3;
1072 i = 1;
1073 while (i < bytes) {
1074 if (curnode->branch == NULL)
1075 {
1076 if (!(curnode->branch = calloc(256,
1077 sizeof (struct ipv6radix))))
1078 return;
1079 }
1080 curnode = &curnode->branch[ip.s6_addr[i]];
1081 i++;
1082 }
1083
1084 curnode->sess = s;
1085
1086 if (s > 0)
1087 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
1088 inet_ntop(AF_INET6, &ip, ipv6addr,
1089 INET6_ADDRSTRLEN),
1090 prefixlen);
1091 else if (s == 0)
1092 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
1093 inet_ntop(AF_INET6, &ip, ipv6addr,
1094 INET6_ADDRSTRLEN),
1095 prefixlen);
1096 }
1097
1098 //
1099 // CLI list to dump current ipcache.
1100 //
1101 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
1102 {
1103 union iphash *d = ip_hash, *e, *f, *g;
1104 int i, j, k, l;
1105 int count = 0;
1106
1107 if (CLI_HELP_REQUESTED)
1108 return CLI_HELP_NO_ARGS;
1109
1110 cli_print(cli, "%7s %s", "Sess#", "IP Address");
1111
1112 for (i = 0; i < 256; ++i)
1113 {
1114 if (!d[i].idx)
1115 continue;
1116
1117 e = d[i].idx;
1118 for (j = 0; j < 256; ++j)
1119 {
1120 if (!e[j].idx)
1121 continue;
1122
1123 f = e[j].idx;
1124 for (k = 0; k < 256; ++k)
1125 {
1126 if (!f[k].idx)
1127 continue;
1128
1129 g = f[k].idx;
1130 for (l = 0; l < 256; ++l)
1131 {
1132 if (!g[l].sess)
1133 continue;
1134
1135 cli_print(cli, "%7d %d.%d.%d.%d", g[l].sess, i, j, k, l);
1136 ++count;
1137 }
1138 }
1139 }
1140 }
1141 cli_print(cli, "%d entries in cache", count);
1142 return CLI_OK;
1143 }
1144
1145
1146 // Find session by username, 0 for not found
1147 // walled garden users aren't authenticated, so the username is
1148 // reasonably useless. Ignore them to avoid incorrect actions
1149 //
1150 // This is VERY inefficent. Don't call it often. :)
1151 //
1152 sessionidt sessionbyuser(char *username)
1153 {
1154 int s;
1155 CSTAT(sessionbyuser);
1156
1157 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1158 {
1159 if (!session[s].opened)
1160 continue;
1161
1162 if (session[s].walled_garden)
1163 continue; // Skip walled garden users.
1164
1165 if (!strncmp(session[s].user, username, 128))
1166 return s;
1167
1168 }
1169 return 0; // Not found.
1170 }
1171
1172 void send_garp(in_addr_t ip)
1173 {
1174 int s;
1175 struct ifreq ifr;
1176 uint8_t mac[6];
1177
1178 s = socket(PF_INET, SOCK_DGRAM, 0);
1179 if (s < 0)
1180 {
1181 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
1182 return;
1183 }
1184 memset(&ifr, 0, sizeof(ifr));
1185 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
1186 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
1187 {
1188 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
1189 close(s);
1190 return;
1191 }
1192 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
1193 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
1194 {
1195 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
1196 close(s);
1197 return;
1198 }
1199 close(s);
1200 sendarp(ifr.ifr_ifindex, mac, ip);
1201 }
1202
1203 static sessiont *sessiontbysessionidt(sessionidt s)
1204 {
1205 if (!s || s >= MAXSESSION) return NULL;
1206 return &session[s];
1207 }
1208
1209 static sessionidt sessionidtbysessiont(sessiont *s)
1210 {
1211 sessionidt val = s-session;
1212 if (s < session || val >= MAXSESSION) return 0;
1213 return val;
1214 }
1215
1216 // actually send a control message for a specific tunnel
1217 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
1218 {
1219 struct sockaddr_in addr;
1220
1221 CSTAT(tunnelsend);
1222
1223 if (!t)
1224 {
1225 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
1226 STAT(tunnel_tx_errors);
1227 return;
1228 }
1229
1230 if (t == TUNNEL_ID_PPPOE)
1231 {
1232 pppoe_sess_send(buf, l, t);
1233 return;
1234 }
1235
1236 if (!tunnel[t].ip)
1237 {
1238 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
1239 STAT(tunnel_tx_errors);
1240 return;
1241 }
1242
1243 memset(&addr, 0, sizeof(addr));
1244 addr.sin_family = AF_INET;
1245 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
1246 addr.sin_port = htons(tunnel[t].port);
1247
1248 // sequence expected, if sequence in message
1249 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
1250
1251 // If this is a control message, deal with retries
1252 if (*buf & 0x80)
1253 {
1254 tunnel[t].last = time_now; // control message sent
1255 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
1256 if (tunnel[t].try)
1257 {
1258 STAT(tunnel_retries);
1259 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
1260 }
1261 }
1262
1263 if (sendto(udpfd[tunnel[t].indexudp], buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
1264 {
1265 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
1266 strerror(errno), udpfd[tunnel[t].indexudp], buf, l, inet_ntoa(addr.sin_addr));
1267 STAT(tunnel_tx_errors);
1268 return;
1269 }
1270
1271 LOG_HEX(5, "Send Tunnel Data", buf, l);
1272 STAT(tunnel_tx_packets);
1273 INC_STAT(tunnel_tx_bytes, l);
1274 }
1275
1276 //
1277 // Tiny helper function to write data to
1278 // the 'tun' device.
1279 //
1280 int tun_write(uint8_t * data, int size)
1281 {
1282 return write(tunfd, data, size);
1283 }
1284
1285 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
1286 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
1287 {
1288 int d = (tcp[12] >> 4) * 4;
1289 uint8_t *mss = 0;
1290 uint8_t *opts;
1291 uint8_t *data;
1292 uint16_t orig;
1293 uint32_t sum;
1294
1295 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1296 return;
1297
1298 if (tcp + d > buf + len) // short?
1299 return;
1300
1301 opts = tcp + 20;
1302 data = tcp + d;
1303
1304 while (opts < data)
1305 {
1306 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1307 {
1308 mss = opts + 2;
1309 if (mss + 2 > data) return; // short?
1310 break;
1311 }
1312
1313 if (*opts == 0) return; // end of options
1314 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1315 opts++;
1316 else
1317 opts += opts[1]; // skip over option
1318 }
1319
1320 if (!mss) return; // not found
1321 orig = ntohs(*(uint16_t *) mss);
1322
1323 if (orig <= MSS) return; // mss OK
1324
1325 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1326 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1327 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1328 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1329
1330 // set mss
1331 *(int16_t *) mss = htons(MSS);
1332
1333 // adjust checksum (see rfc1141)
1334 sum = orig + (~MSS & 0xffff);
1335 sum += ntohs(*(uint16_t *) (tcp + 16));
1336 sum = (sum & 0xffff) + (sum >> 16);
1337 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1338 }
1339
1340 void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra)
1341 {
1342 uint16_t proto;
1343 if (extra) {
1344 // Skip the four extra bytes
1345 p += 4;
1346 l -= 4;
1347 }
1348
1349 if (*p & 1)
1350 {
1351 proto = *p++;
1352 l--;
1353 }
1354 else
1355 {
1356 proto = ntohs(*(uint16_t *) p);
1357 p += 2;
1358 l -= 2;
1359 }
1360 if (proto == PPPIP)
1361 {
1362 if (session[s].die)
1363 {
1364 LOG(4, s, t, "MPPP: Session %d is closing. Don't process PPP packets\n", s);
1365 return; // closing session, PPP not processed
1366 }
1367 session[s].last_packet = session[s].last_data = time_now;
1368 processipin(s, t, p, l);
1369 }
1370 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
1371 {
1372 if (session[s].die)
1373 {
1374 LOG(4, s, t, "MPPP: Session %d is closing. Don't process PPP packets\n", s);
1375 return; // closing session, PPP not processed
1376 }
1377
1378 session[s].last_packet = session[s].last_data = time_now;
1379 processipv6in(s, t, p, l);
1380 }
1381 else if (proto == PPPIPCP)
1382 {
1383 session[s].last_packet = session[s].last_data = time_now;
1384 processipcp(s, t, p, l);
1385 }
1386 else if (proto == PPPCCP)
1387 {
1388 session[s].last_packet = session[s].last_data = time_now;
1389 processccp(s, t, p, l);
1390 }
1391 else
1392 {
1393 LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto);
1394 }
1395 }
1396
1397 static void update_session_out_stat(sessionidt s, sessiont *sp, int len)
1398 {
1399 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1400 sp->cout_delta += len;
1401 sp->pout++;
1402 sp->last_data = time_now;
1403
1404 sess_local[s].cout += len; // To send to master..
1405 sess_local[s].pout++;
1406 }
1407
1408 // process outgoing (to tunnel) IP
1409 //
1410 // (i.e. this routine writes to data[-8]).
1411 void processipout(uint8_t *buf, int len)
1412 {
1413 sessionidt s;
1414 sessiont *sp;
1415 tunnelidt t;
1416 in_addr_t ip;
1417
1418 uint8_t *data = buf; // Keep a copy of the originals.
1419 int size = len;
1420
1421 uint8_t fragbuf[MAXETHER + 20];
1422
1423 CSTAT(processipout);
1424
1425 if (len < MIN_IP_SIZE)
1426 {
1427 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1428 STAT(tun_rx_errors);
1429 return;
1430 }
1431 if (len >= MAXETHER)
1432 {
1433 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1434 STAT(tun_rx_errors);
1435 return;
1436 }
1437
1438 // Skip the tun header
1439 buf += 4;
1440 len -= 4;
1441
1442 // Got an IP header now
1443 if (*(uint8_t *)(buf) >> 4 != 4)
1444 {
1445 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1446 return;
1447 }
1448
1449 ip = *(uint32_t *)(buf + 16);
1450 if (!(s = sessionbyip(ip)))
1451 {
1452 // Is this a packet for a session that doesn't exist?
1453 static int rate = 0; // Number of ICMP packets we've sent this second.
1454 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1455
1456 if (last != time_now)
1457 {
1458 last = time_now;
1459 rate = 0;
1460 }
1461
1462 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1463 {
1464 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1465 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1466 config->bind_address ? config->bind_address : my_address, buf, len);
1467 }
1468 return;
1469 }
1470
1471 t = session[s].tunnel;
1472 if (len > session[s].mru || (session[s].mrru && len > session[s].mrru))
1473 {
1474 LOG(3, s, t, "Packet size more than session MRU\n");
1475 return;
1476 }
1477
1478 sp = &session[s];
1479
1480 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1481 if (config->max_packets > 0)
1482 {
1483 if (sess_local[s].last_packet_out == TIME)
1484 {
1485 int max = config->max_packets;
1486
1487 // All packets for throttled sessions are handled by the
1488 // master, so further limit by using the throttle rate.
1489 // A bit of a kludge, since throttle rate is in kbps,
1490 // but should still be generous given our average DSL
1491 // packet size is 200 bytes: a limit of 28kbps equates
1492 // to around 180 packets per second.
1493 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1494 max = sp->throttle_out;
1495
1496 if (++sess_local[s].packets_out > max)
1497 {
1498 sess_local[s].packets_dropped++;
1499 return;
1500 }
1501 }
1502 else
1503 {
1504 if (sess_local[s].packets_dropped)
1505 {
1506 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1507 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1508 sess_local[s].packets_dropped, sess_local[s].packets_out,
1509 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1510 sp->user);
1511 }
1512
1513 sess_local[s].last_packet_out = TIME;
1514 sess_local[s].packets_out = 1;
1515 sess_local[s].packets_dropped = 0;
1516 }
1517 }
1518
1519 // run access-list if any
1520 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1521 return;
1522
1523 // adjust MSS on SYN and SYN,ACK packets with options
1524 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1525 {
1526 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1527 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1528 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1529 }
1530
1531 if (sp->tbf_out)
1532 {
1533 // Are we throttling this session?
1534 if (config->cluster_iam_master)
1535 tbf_queue_packet(sp->tbf_out, data, size);
1536 else
1537 master_throttle_packet(sp->tbf_out, data, size);
1538 return;
1539 }
1540
1541 if (sp->walled_garden && !config->cluster_iam_master)
1542 {
1543 // We are walled-gardening this
1544 master_garden_packet(s, data, size);
1545 return;
1546 }
1547
1548 if(session[s].bundle != 0 && bundle[session[s].bundle].num_of_links > 1)
1549 {
1550
1551 if (!config->cluster_iam_master)
1552 {
1553 // The MPPP packets must be managed by the Master.
1554 master_forward_mppp_packet(s, data, size);
1555 return;
1556 }
1557
1558 // Add on L2TP header
1559 sessionidt members[MAXBUNDLESES];
1560 bundleidt bid = session[s].bundle;
1561 bundlet *b = &bundle[bid];
1562 uint32_t num_of_links, nb_opened;
1563 int i;
1564
1565 num_of_links = b->num_of_links;
1566 nb_opened = 0;
1567 for (i = 0;i < num_of_links;i++)
1568 {
1569 s = b->members[i];
1570 if (session[s].ppp.lcp == Opened)
1571 {
1572 members[nb_opened] = s;
1573 nb_opened++;
1574 }
1575 }
1576
1577 if (nb_opened < 1)
1578 {
1579 LOG(3, s, t, "MPPP: PROCESSIPOUT ERROR, no session opened in bundle:%d\n", bid);
1580 return;
1581 }
1582
1583 num_of_links = nb_opened;
1584 b->current_ses = (b->current_ses + 1) % num_of_links;
1585 s = members[b->current_ses];
1586 t = session[s].tunnel;
1587 sp = &session[s];
1588 LOG(4, s, t, "MPPP: (1)Session number becomes: %d\n", s);
1589
1590 if (num_of_links > 1)
1591 {
1592 if(len > MINFRAGLEN)
1593 {
1594 //for rotate traffic among the member links
1595 uint32_t divisor = num_of_links;
1596 if (divisor > 2)
1597 divisor = divisor/2 + (divisor & 1);
1598
1599 // Partition the packet to "num_of_links" fragments
1600 uint32_t fraglen = len / divisor;
1601 uint32_t last_fraglen = fraglen + len % divisor;
1602 uint32_t remain = len;
1603
1604 // send the first packet
1605 uint8_t *p = makeppp(fragbuf, sizeof(fragbuf), buf, fraglen, s, t, PPPIP, 0, bid, MP_BEGIN);
1606 if (!p) return;
1607 tunnelsend(fragbuf, fraglen + (p-fragbuf), t); // send it...
1608
1609 // statistics
1610 update_session_out_stat(s, sp, fraglen);
1611
1612 remain -= fraglen;
1613 while (remain > last_fraglen)
1614 {
1615 b->current_ses = (b->current_ses + 1) % num_of_links;
1616 s = members[b->current_ses];
1617 t = session[s].tunnel;
1618 sp = &session[s];
1619 LOG(4, s, t, "MPPP: (2)Session number becomes: %d\n", s);
1620 p = makeppp(fragbuf, sizeof(fragbuf), buf+(len - remain), fraglen, s, t, PPPIP, 0, bid, 0);
1621 if (!p) return;
1622 tunnelsend(fragbuf, fraglen + (p-fragbuf), t); // send it...
1623 update_session_out_stat(s, sp, fraglen);
1624 remain -= fraglen;
1625 }
1626 // send the last fragment
1627 b->current_ses = (b->current_ses + 1) % num_of_links;
1628 s = members[b->current_ses];
1629 t = session[s].tunnel;
1630 sp = &session[s];
1631 LOG(4, s, t, "MPPP: (2)Session number becomes: %d\n", s);
1632 p = makeppp(fragbuf, sizeof(fragbuf), buf+(len - remain), remain, s, t, PPPIP, 0, bid, MP_END);
1633 if (!p) return;
1634 tunnelsend(fragbuf, remain + (p-fragbuf), t); // send it...
1635 update_session_out_stat(s, sp, remain);
1636 if (remain != last_fraglen)
1637 LOG(3, s, t, "PROCESSIPOUT ERROR REMAIN != LAST_FRAGLEN, %d != %d\n", remain, last_fraglen);
1638 }
1639 else
1640 {
1641 // Send it as one frame
1642 uint8_t *p = makeppp(fragbuf, sizeof(fragbuf), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS);
1643 if (!p) return;
1644 tunnelsend(fragbuf, len + (p-fragbuf), t); // send it...
1645 LOG(4, s, t, "MPPP: packet sent as one frame\n");
1646 update_session_out_stat(s, sp, len);
1647 }
1648 }
1649 else
1650 {
1651 // Send it as one frame (NO MPPP Frame)
1652 uint8_t *p = opt_makeppp(buf, len, s, t, PPPIP, 0, 0, 0);
1653 tunnelsend(p, len + (buf-p), t); // send it...
1654 update_session_out_stat(s, sp, len);
1655 }
1656 }
1657 else
1658 {
1659 uint8_t *p = opt_makeppp(buf, len, s, t, PPPIP, 0, 0, 0);
1660 tunnelsend(p, len + (buf-p), t); // send it...
1661 update_session_out_stat(s, sp, len);
1662 }
1663
1664 // Snooping this session, send it to intercept box
1665 if (sp->snoop_ip && sp->snoop_port)
1666 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1667
1668 udp_tx += len;
1669 }
1670
1671 // process outgoing (to tunnel) IPv6
1672 //
1673 static void processipv6out(uint8_t * buf, int len)
1674 {
1675 sessionidt s;
1676 sessiont *sp;
1677 tunnelidt t;
1678 in_addr_t ip;
1679 struct in6_addr ip6;
1680
1681 uint8_t *data = buf; // Keep a copy of the originals.
1682 int size = len;
1683
1684 uint8_t b[MAXETHER + 20];
1685
1686 CSTAT(processipv6out);
1687
1688 if (len < MIN_IP_SIZE)
1689 {
1690 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1691 STAT(tunnel_tx_errors);
1692 return;
1693 }
1694 if (len >= MAXETHER)
1695 {
1696 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1697 STAT(tunnel_tx_errors);
1698 return;
1699 }
1700
1701 // Skip the tun header
1702 buf += 4;
1703 len -= 4;
1704
1705 // Got an IP header now
1706 if (*(uint8_t *)(buf) >> 4 != 6)
1707 {
1708 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1709 return;
1710 }
1711
1712 ip6 = *(struct in6_addr *)(buf+24);
1713 s = sessionbyipv6(ip6);
1714
1715 if (s == 0)
1716 {
1717 ip = *(uint32_t *)(buf + 32);
1718 s = sessionbyip(ip);
1719 }
1720
1721 if (s == 0)
1722 {
1723 // Is this a packet for a session that doesn't exist?
1724 static int rate = 0; // Number of ICMP packets we've sent this second.
1725 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1726
1727 if (last != time_now)
1728 {
1729 last = time_now;
1730 rate = 0;
1731 }
1732
1733 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1734 {
1735 // FIXME: Should send icmp6 host unreachable
1736 }
1737 return;
1738 }
1739 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1740 {
1741 bundleidt bid = session[s].bundle;
1742 bundlet *b = &bundle[bid];
1743
1744 b->current_ses = (b->current_ses + 1) % b->num_of_links;
1745 s = b->members[b->current_ses];
1746 LOG(3, s, session[s].tunnel, "MPPP: Session number becomes: %u\n", s);
1747 }
1748 t = session[s].tunnel;
1749 sp = &session[s];
1750 sp->last_data = time_now;
1751
1752 // FIXME: add DoS prevention/filters?
1753
1754 if (sp->tbf_out)
1755 {
1756 // Are we throttling this session?
1757 if (config->cluster_iam_master)
1758 tbf_queue_packet(sp->tbf_out, data, size);
1759 else
1760 master_throttle_packet(sp->tbf_out, data, size);
1761 return;
1762 }
1763 else if (sp->walled_garden && !config->cluster_iam_master)
1764 {
1765 // We are walled-gardening this
1766 master_garden_packet(s, data, size);
1767 return;
1768 }
1769
1770 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1771
1772 // Add on L2TP header
1773 {
1774 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6, 0, 0, 0);
1775 if (!p) return;
1776 tunnelsend(b, len + (p-b), t); // send it...
1777 }
1778
1779 // Snooping this session, send it to intercept box
1780 if (sp->snoop_ip && sp->snoop_port)
1781 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1782
1783 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1784 sp->cout_delta += len;
1785 sp->pout++;
1786 udp_tx += len;
1787
1788 sess_local[s].cout += len; // To send to master..
1789 sess_local[s].pout++;
1790 }
1791
1792 //
1793 // Helper routine for the TBF filters.
1794 // Used to send queued data in to the user!
1795 //
1796 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1797 {
1798 sessiont *sp;
1799 tunnelidt t;
1800
1801 uint8_t b[MAXETHER + 20];
1802
1803 if (len < 0 || len > MAXETHER)
1804 {
1805 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1806 return;
1807 }
1808
1809 // Skip the tun header
1810 buf += 4;
1811 len -= 4;
1812
1813 if (!session[s].ip)
1814 return;
1815
1816 t = session[s].tunnel;
1817 sp = &session[s];
1818
1819 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1820
1821 // Add on L2TP header
1822 {
1823 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP, 0, 0, 0);
1824 if (!p) return;
1825 tunnelsend(b, len + (p-b), t); // send it...
1826 }
1827
1828 // Snooping this session.
1829 if (sp->snoop_ip && sp->snoop_port)
1830 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1831
1832 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1833 sp->cout_delta += len;
1834 sp->pout++;
1835 udp_tx += len;
1836
1837 sess_local[s].cout += len; // To send to master..
1838 sess_local[s].pout++;
1839 }
1840
1841 // add an AVP (16 bit)
1842 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1843 {
1844 uint16_t l = (m ? 0x8008 : 0x0008);
1845 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1846 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1847 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1848 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1849 c->length += 8;
1850 }
1851
1852 // add an AVP (32 bit)
1853 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1854 {
1855 uint16_t l = (m ? 0x800A : 0x000A);
1856 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1857 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1858 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1859 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1860 c->length += 10;
1861 }
1862
1863 // add an AVP (string)
1864 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1865 {
1866 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1867 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1868 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1869 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1870 memcpy(c->buf + c->length + 6, val, strlen(val));
1871 c->length += 6 + strlen(val);
1872 }
1873
1874 // add a binary AVP
1875 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1876 {
1877 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1878 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1879 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1880 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1881 memcpy(c->buf + c->length + 6, val, len);
1882 c->length += 6 + len;
1883 }
1884
1885 // new control connection
1886 static controlt *controlnew(uint16_t mtype)
1887 {
1888 controlt *c;
1889 if (!controlfree)
1890 c = malloc(sizeof(controlt));
1891 else
1892 {
1893 c = controlfree;
1894 controlfree = c->next;
1895 }
1896 assert(c);
1897 c->next = 0;
1898 c->buf[0] = 0xC8; // flags
1899 c->buf[1] = 0x02; // ver
1900 c->length = 12;
1901 control16(c, 0, mtype, 1);
1902 return c;
1903 }
1904
1905 // send zero block if nothing is waiting
1906 // (ZLB send).
1907 static void controlnull(tunnelidt t)
1908 {
1909 uint16_t buf[6];
1910 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1911 return;
1912
1913 buf[0] = htons(0xC802); // flags/ver
1914 buf[1] = htons(12); // length
1915 buf[2] = htons(tunnel[t].far); // tunnel
1916 buf[3] = htons(0); // session
1917 buf[4] = htons(tunnel[t].ns); // sequence
1918 buf[5] = htons(tunnel[t].nr); // sequence
1919 tunnelsend((uint8_t *)buf, 12, t);
1920 }
1921
1922 // add a control message to a tunnel, and send if within window
1923 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1924 {
1925 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1926 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1927 *(uint16_t *) (c->buf + 6) = htons(far); // session
1928 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1929 tunnel[t].ns++; // advance sequence
1930 // link in message in to queue
1931 if (tunnel[t].controlc)
1932 tunnel[t].controle->next = c;
1933 else
1934 tunnel[t].controls = c;
1935
1936 tunnel[t].controle = c;
1937 tunnel[t].controlc++;
1938
1939 // send now if space in window
1940 if (tunnel[t].controlc <= tunnel[t].window)
1941 {
1942 tunnel[t].try = 0; // first send
1943 tunnelsend(c->buf, c->length, t);
1944 }
1945 }
1946
1947 //
1948 // Throttle or Unthrottle a session
1949 //
1950 // Throttle the data from/to through a session to no more than
1951 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1952 // user).
1953 //
1954 // If either value is -1, the current value is retained for that
1955 // direction.
1956 //
1957 void throttle_session(sessionidt s, int rate_in, int rate_out)
1958 {
1959 if (!session[s].opened)
1960 return; // No-one home.
1961
1962 if (!*session[s].user)
1963 return; // User not logged in
1964
1965 if (rate_in >= 0)
1966 {
1967 int bytes = rate_in * 1024 / 8; // kbits to bytes
1968 if (session[s].tbf_in)
1969 free_tbf(session[s].tbf_in);
1970
1971 if (rate_in > 0)
1972 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1973 else
1974 session[s].tbf_in = 0;
1975
1976 session[s].throttle_in = rate_in;
1977 }
1978
1979 if (rate_out >= 0)
1980 {
1981 int bytes = rate_out * 1024 / 8;
1982 if (session[s].tbf_out)
1983 free_tbf(session[s].tbf_out);
1984
1985 if (rate_out > 0)
1986 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1987 else
1988 session[s].tbf_out = 0;
1989
1990 session[s].throttle_out = rate_out;
1991 }
1992 }
1993
1994 // add/remove filters from session (-1 = no change)
1995 void filter_session(sessionidt s, int filter_in, int filter_out)
1996 {
1997 if (!session[s].opened)
1998 return; // No-one home.
1999
2000 if (!*session[s].user)
2001 return; // User not logged in
2002
2003 // paranoia
2004 if (filter_in > MAXFILTER) filter_in = -1;
2005 if (filter_out > MAXFILTER) filter_out = -1;
2006 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
2007 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
2008
2009 if (filter_in >= 0)
2010 {
2011 if (session[s].filter_in)
2012 ip_filters[session[s].filter_in - 1].used--;
2013
2014 if (filter_in > 0)
2015 ip_filters[filter_in - 1].used++;
2016
2017 session[s].filter_in = filter_in;
2018 }
2019
2020 if (filter_out >= 0)
2021 {
2022 if (session[s].filter_out)
2023 ip_filters[session[s].filter_out - 1].used--;
2024
2025 if (filter_out > 0)
2026 ip_filters[filter_out - 1].used++;
2027
2028 session[s].filter_out = filter_out;
2029 }
2030 }
2031
2032 // start tidy shutdown of session
2033 void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause)
2034 {
2035 int walled_garden = session[s].walled_garden;
2036 bundleidt b = session[s].bundle;
2037 //delete routes only for last session in bundle (in case of MPPP)
2038 int del_routes = !b || (bundle[b].num_of_links == 1);
2039
2040 CSTAT(sessionshutdown);
2041
2042 if (!session[s].opened)
2043 {
2044 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
2045 return; // not a live session
2046 }
2047
2048 if (!session[s].die)
2049 {
2050 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
2051 LOG(2, s, session[s].tunnel, "Shutting down session %u: %s\n", s, reason);
2052 run_plugins(PLUGIN_KILL_SESSION, &data);
2053 }
2054
2055 if (session[s].ip && !walled_garden && !session[s].die)
2056 {
2057 // RADIUS Stop message
2058 uint16_t r = radiusnew(s);
2059 if (r)
2060 {
2061 // stop, if not already trying
2062 if (radius[r].state != RADIUSSTOP)
2063 {
2064 radius[r].term_cause = term_cause;
2065 radius[r].term_msg = reason;
2066 radiussend(r, RADIUSSTOP);
2067 }
2068 }
2069 else
2070 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
2071
2072 // Save counters to dump to accounting file
2073 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
2074 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
2075 }
2076
2077 if (!session[s].die)
2078 session[s].die = TIME + 150; // Clean up in 15 seconds
2079
2080 if (session[s].ip)
2081 { // IP allocated, clear and unroute
2082 int r;
2083 int routed = 0;
2084 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
2085 {
2086 if ((session[s].ip >> (32-session[s].route[r].prefixlen)) ==
2087 (session[s].route[r].ip >> (32-session[s].route[r].prefixlen)))
2088 routed++;
2089
2090 if (del_routes) routeset(s, session[s].route[r].ip, session[s].route[r].prefixlen, 0, 0);
2091 session[s].route[r].ip = 0;
2092 }
2093
2094 if (session[s].ip_pool_index == -1) // static ip
2095 {
2096 if (!routed && del_routes) routeset(s, session[s].ip, 0, 0, 0);
2097 session[s].ip = 0;
2098 }
2099 else
2100 free_ip_address(s);
2101
2102 // unroute IPv6, if setup
2103 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen && del_routes)
2104 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
2105
2106 if (b)
2107 {
2108 // This session was part of a bundle
2109 bundle[b].num_of_links--;
2110 LOG(3, s, session[s].tunnel, "MPPP: Dropping member link: %d from bundle %d\n",s,b);
2111 if(bundle[b].num_of_links == 0)
2112 {
2113 bundleclear(b);
2114 LOG(3, s, session[s].tunnel, "MPPP: Kill bundle: %d (No remaing member links)\n",b);
2115 }
2116 else
2117 {
2118 // Adjust the members array to accomodate the new change
2119 uint8_t mem_num = 0;
2120 // It should be here num_of_links instead of num_of_links-1 (previous instruction "num_of_links--")
2121 if(bundle[b].members[bundle[b].num_of_links] != s)
2122 {
2123 uint8_t ml;
2124 for(ml = 0; ml<bundle[b].num_of_links; ml++)
2125 if(bundle[b].members[ml] == s)
2126 {
2127 mem_num = ml;
2128 break;
2129 }
2130 bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
2131 LOG(3, s, session[s].tunnel, "MPPP: Adjusted member links array\n");
2132
2133 // If the killed session is the first of the bundle,
2134 // the new first session must be stored in the cache_ipmap
2135 // else the function sessionbyip return 0 and the sending not work any more (processipout).
2136 if (mem_num == 0)
2137 {
2138 sessionidt new_s = bundle[b].members[0];
2139
2140 routed = 0;
2141 // Add the route for this session.
2142 for (r = 0; r < MAXROUTE && session[new_s].route[r].ip; r++)
2143 {
2144 int i, prefixlen;
2145 in_addr_t ip;
2146
2147 prefixlen = session[new_s].route[r].prefixlen;
2148 ip = session[new_s].route[r].ip;
2149
2150 if (!prefixlen) prefixlen = 32;
2151 ip &= 0xffffffff << (32 - prefixlen); // Force the ip to be the first one in the route.
2152
2153 for (i = ip; i < ip+(1<<(32-prefixlen)) ; ++i)
2154 cache_ipmap(i, new_s);
2155 }
2156 cache_ipmap(session[new_s].ip, new_s);
2157
2158 // IPV6 route
2159 if (session[new_s].ipv6prefixlen)
2160 cache_ipv6map(session[new_s].ipv6route, session[new_s].ipv6prefixlen, new_s);
2161 }
2162 }
2163 }
2164
2165 cluster_send_bundle(b);
2166 }
2167 }
2168
2169 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
2170 throttle_session(s, 0, 0);
2171
2172 if (cdn_result)
2173 {
2174 if (session[s].tunnel == TUNNEL_ID_PPPOE)
2175 {
2176 pppoe_shutdown_session(s);
2177 }
2178 else
2179 {
2180 // Send CDN
2181 controlt *c = controlnew(14); // sending CDN
2182 if (cdn_error)
2183 {
2184 uint16_t buf[2];
2185 buf[0] = htons(cdn_result);
2186 buf[1] = htons(cdn_error);
2187 controlb(c, 1, (uint8_t *)buf, 4, 1);
2188 }
2189 else
2190 control16(c, 1, cdn_result, 1);
2191
2192 control16(c, 14, s, 1); // assigned session (our end)
2193 controladd(c, session[s].far, session[s].tunnel); // send the message
2194 }
2195 }
2196
2197 // update filter refcounts
2198 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
2199 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
2200
2201 // clear PPP state
2202 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
2203 sess_local[s].lcp.restart = 0;
2204 sess_local[s].ipcp.restart = 0;
2205 sess_local[s].ipv6cp.restart = 0;
2206 sess_local[s].ccp.restart = 0;
2207
2208 cluster_send_session(s);
2209 }
2210
2211 void sendipcp(sessionidt s, tunnelidt t)
2212 {
2213 uint8_t buf[MAXETHER];
2214 uint8_t *q;
2215
2216 CSTAT(sendipcp);
2217 LOG(3, s, t, "IPCP: send ConfigReq\n");
2218
2219 if (!session[s].unique_id)
2220 {
2221 if (!++last_id) ++last_id; // skip zero
2222 session[s].unique_id = last_id;
2223 }
2224
2225 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP, 0, 0, 0);
2226 if (!q) return;
2227
2228 *q = ConfigReq;
2229 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
2230 *(uint16_t *) (q + 2) = htons(10); // packet length
2231 q[4] = 3; // ip address option
2232 q[5] = 6; // option length
2233 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
2234 config->iftun_n_address[tunnel[t].indexudp] ? config->iftun_n_address[tunnel[t].indexudp] :
2235 my_address; // send my IP
2236
2237 tunnelsend(buf, 10 + (q - buf), t); // send it
2238 restart_timer(s, ipcp);
2239 }
2240
2241 void sendipv6cp(sessionidt s, tunnelidt t)
2242 {
2243 uint8_t buf[MAXETHER];
2244 uint8_t *q;
2245
2246 CSTAT(sendipv6cp);
2247 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
2248
2249 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP, 0, 0, 0);
2250 if (!q) return;
2251
2252 *q = ConfigReq;
2253 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
2254 // only send one type
2255 // of request
2256 *(uint16_t *) (q + 2) = htons(14);
2257 q[4] = 1; // interface identifier option
2258 q[5] = 10; // option length
2259 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
2260 *(uint32_t *) (q + 10) = 0;
2261 q[13] = 1;
2262
2263 tunnelsend(buf, 14 + (q - buf), t); // send it
2264 restart_timer(s, ipv6cp);
2265 }
2266
2267 static void sessionclear(sessionidt s)
2268 {
2269 memset(&session[s], 0, sizeof(session[s]));
2270 memset(&sess_local[s], 0, sizeof(sess_local[s]));
2271 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
2272
2273 session[s].tunnel = T_FREE; // Mark it as free.
2274 session[s].next = sessionfree;
2275 sessionfree = s;
2276 }
2277
2278 // kill a session now
2279 void sessionkill(sessionidt s, char *reason)
2280 {
2281 CSTAT(sessionkill);
2282
2283 if (!session[s].opened) // not alive
2284 return;
2285
2286 if (session[s].next)
2287 {
2288 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%u)\n", session[s].next);
2289 return;
2290 }
2291
2292 if (!session[s].die)
2293 sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
2294
2295 if (sess_local[s].radius)
2296 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
2297
2298 if (session[s].forwardtosession)
2299 {
2300 sessionidt sess = session[s].forwardtosession;
2301 if (session[sess].forwardtosession == s)
2302 {
2303 // Shutdown the linked session also.
2304 sessionshutdown(sess, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET);
2305 }
2306 }
2307
2308 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
2309 sessionclear(s);
2310 cluster_send_session(s);
2311 }
2312
2313 static void tunnelclear(tunnelidt t)
2314 {
2315 if (!t) return;
2316 memset(&tunnel[t], 0, sizeof(tunnel[t]));
2317 tunnel[t].state = TUNNELFREE;
2318 }
2319
2320 static void bundleclear(bundleidt b)
2321 {
2322 if (!b) return;
2323 memset(&bundle[b], 0, sizeof(bundle[b]));
2324 bundle[b].state = BUNDLEFREE;
2325 }
2326
2327 // kill a tunnel now
2328 static void tunnelkill(tunnelidt t, char *reason)
2329 {
2330 sessionidt s;
2331 controlt *c;
2332
2333 CSTAT(tunnelkill);
2334
2335 tunnel[t].state = TUNNELDIE;
2336
2337 // free control messages
2338 while ((c = tunnel[t].controls))
2339 {
2340 controlt * n = c->next;
2341 tunnel[t].controls = n;
2342 tunnel[t].controlc--;
2343 c->next = controlfree;
2344 controlfree = c;
2345 }
2346 // kill sessions
2347 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
2348 if (session[s].tunnel == t)
2349 sessionkill(s, reason);
2350
2351 // free tunnel
2352 tunnelclear(t);
2353 LOG(1, 0, t, "Kill tunnel %u: %s\n", t, reason);
2354 cli_tunnel_actions[t].action = 0;
2355 cluster_send_tunnel(t);
2356 }
2357
2358 // shut down a tunnel cleanly
2359 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
2360 {
2361 sessionidt s;
2362
2363 CSTAT(tunnelshutdown);
2364
2365 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
2366 {
2367 // never set up, can immediately kill
2368 tunnelkill(t, reason);
2369 return;
2370 }
2371 LOG(1, 0, t, "Shutting down tunnel %u (%s)\n", t, reason);
2372
2373 // close session
2374 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
2375 if (session[s].tunnel == t)
2376 sessionshutdown(s, reason, CDN_NONE, TERM_ADMIN_RESET);
2377
2378 tunnel[t].state = TUNNELDIE;
2379 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
2380 cluster_send_tunnel(t);
2381 // TBA - should we wait for sessions to stop?
2382 if (result)
2383 {
2384 controlt *c = controlnew(4); // sending StopCCN
2385 if (error)
2386 {
2387 uint16_t buf[32];
2388 int l = 4;
2389 buf[0] = htons(result);
2390 buf[1] = htons(error);
2391 if (msg)
2392 {
2393 int m = strlen(msg);
2394 if (m + 4 > sizeof(buf))
2395 m = sizeof(buf) - 4;
2396
2397 memcpy(buf+2, msg, m);
2398 l += m;
2399 }
2400
2401 controlb(c, 1, (uint8_t *)buf, l, 1);
2402 }
2403 else
2404 control16(c, 1, result, 1);
2405
2406 control16(c, 9, t, 1); // assigned tunnel (our end)
2407 controladd(c, 0, t); // send the message
2408 }
2409 }
2410
2411 // read and process packet on tunnel (UDP)
2412 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr, uint16_t indexudpfd)
2413 {
2414 uint8_t *chapresponse = NULL;
2415 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
2416 uint8_t *p = buf + 2;
2417
2418
2419 CSTAT(processudp);
2420
2421 udp_rx += len;
2422 udp_rx_pkt++;
2423 LOG_HEX(5, "UDP Data", buf, len);
2424 STAT(tunnel_rx_packets);
2425 INC_STAT(tunnel_rx_bytes, len);
2426 if (len < 6)
2427 {
2428 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
2429 STAT(tunnel_rx_errors);
2430 return;
2431 }
2432 if ((buf[1] & 0x0F) != 2)
2433 {
2434 LOG(1, 0, 0, "Bad L2TP ver %d\n", buf[1] & 0x0F);
2435 STAT(tunnel_rx_errors);
2436 return;
2437 }
2438 if (*buf & 0x40)
2439 { // length
2440 l = ntohs(*(uint16_t *) p);
2441 p += 2;
2442 }
2443 t = ntohs(*(uint16_t *) p);
2444 p += 2;
2445 s = ntohs(*(uint16_t *) p);
2446 p += 2;
2447 if (s >= MAXSESSION)
2448 {
2449 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
2450 STAT(tunnel_rx_errors);
2451 return;
2452 }
2453 if (t >= MAXTUNNEL)
2454 {
2455 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
2456 STAT(tunnel_rx_errors);
2457 return;
2458 }
2459 if (t == TUNNEL_ID_PPPOE)
2460 {
2461 LOG(1, s, t, "Received UDP packet with tunnel ID reserved for pppoe\n");
2462 STAT(tunnel_rx_errors);
2463 return;
2464 }
2465 if (*buf & 0x08)
2466 { // ns/nr
2467 ns = ntohs(*(uint16_t *) p);
2468 p += 2;
2469 nr = ntohs(*(uint16_t *) p);
2470 p += 2;
2471 }
2472 if (*buf & 0x02)
2473 { // offset
2474 uint16_t o = ntohs(*(uint16_t *) p);
2475 p += o + 2;
2476 }
2477 if ((p - buf) > l)
2478 {
2479 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
2480 STAT(tunnel_rx_errors);
2481 return;
2482 }
2483 l -= (p - buf);
2484
2485 // used to time out old tunnels
2486 if (t && tunnel[t].state == TUNNELOPEN)
2487 tunnel[t].lastrec = time_now;
2488
2489 if (*buf & 0x80)
2490 { // control
2491 uint16_t message = 0xFFFF; // message type
2492 uint8_t fatal = 0;
2493 uint8_t mandatory = 0;
2494 uint16_t asession = 0; // assigned session
2495 uint32_t amagic = 0; // magic number
2496 uint8_t aflags = 0; // flags from last LCF
2497 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
2498 char called[MAXTEL] = ""; // called number
2499 char calling[MAXTEL] = ""; // calling number
2500
2501 if (!config->cluster_iam_master)
2502 {
2503 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd);
2504 return;
2505 }
2506
2507 // control messages must have bits 0x80|0x40|0x08
2508 // (type, length and sequence) set, and bits 0x02|0x01
2509 // (offset and priority) clear
2510 if ((*buf & 0xCB) != 0xC8)
2511 {
2512 LOG(1, s, t, "Bad control header %02X\n", *buf);
2513 STAT(tunnel_rx_errors);
2514 return;
2515 }
2516
2517 // check for duplicate tunnel open message
2518 if (!t && ns == 0)
2519 {
2520 int i;
2521
2522 //
2523 // Is this a duplicate of the first packet? (SCCRQ)
2524 //
2525 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
2526 {
2527 if (tunnel[i].state != TUNNELOPENING ||
2528 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
2529 tunnel[i].port != ntohs(addr->sin_port) )
2530 continue;
2531 t = i;
2532 LOG(3, s, t, "Duplicate SCCRQ?\n");
2533 break;
2534 }
2535 }
2536
2537 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %u l-nr %u r-ns %u r-nr %u\n",
2538 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
2539
2540 // if no tunnel specified, assign one
2541 if (!t)
2542 {
2543 if (!(t = new_tunnel()))
2544 {
2545 LOG(1, 0, 0, "No more tunnels\n");
2546 STAT(tunnel_overflow);
2547 return;
2548 }
2549 tunnelclear(t);
2550 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
2551 tunnel[t].port = ntohs(addr->sin_port);
2552 tunnel[t].window = 4; // default window
2553 tunnel[t].indexudp = indexudpfd;
2554 STAT(tunnel_created);
2555 LOG(1, 0, t, " New tunnel from %s:%u ID %u\n",
2556 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
2557 }
2558
2559 // If the 'ns' just received is not the 'nr' we're
2560 // expecting, just send an ack and drop it.
2561 //
2562 // if 'ns' is less, then we got a retransmitted packet.
2563 // if 'ns' is greater than missed a packet. Either way
2564 // we should ignore it.
2565 if (ns != tunnel[t].nr)
2566 {
2567 // is this the sequence we were expecting?
2568 STAT(tunnel_rx_errors);
2569 LOG(1, 0, t, " Out of sequence tunnel %u, (%u is not the expected %u)\n",
2570 t, ns, tunnel[t].nr);
2571
2572 if (l) // Is this not a ZLB?
2573 controlnull(t);
2574 return;
2575 }
2576
2577 // check sequence of this message
2578 {
2579 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2580 // some to clear maybe?
2581 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2582 {
2583 controlt *c = tunnel[t].controls;
2584 tunnel[t].controls = c->next;
2585 tunnel[t].controlc--;
2586 c->next = controlfree;
2587 controlfree = c;
2588 skip--;
2589 tunnel[t].try = 0; // we have progress
2590 }
2591
2592 // receiver advance (do here so quoted correctly in any sends below)
2593 if (l) tunnel[t].nr = (ns + 1);
2594 if (skip < 0) skip = 0;
2595 if (skip < tunnel[t].controlc)
2596 {
2597 // some control packets can now be sent that were previous stuck out of window
2598 int tosend = tunnel[t].window - skip;
2599 controlt *c = tunnel[t].controls;
2600 while (c && skip)
2601 {
2602 c = c->next;
2603 skip--;
2604 }
2605 while (c && tosend)
2606 {
2607 tunnel[t].try = 0; // first send
2608 tunnelsend(c->buf, c->length, t);
2609 c = c->next;
2610 tosend--;
2611 }
2612 }
2613 if (!tunnel[t].controlc)
2614 tunnel[t].retry = 0; // caught up
2615 }
2616 if (l)
2617 { // if not a null message
2618 int result = 0;
2619 int error = 0;
2620 char *msg = 0;
2621
2622 // Default disconnect cause/message on receipt of CDN. Set to
2623 // more specific value from attribute 1 (result code) or 46
2624 // (disconnect cause) if present below.
2625 int disc_cause_set = 0;
2626 int disc_cause = TERM_NAS_REQUEST;
2627 char const *disc_reason = "Closed (Received CDN).";
2628
2629 // process AVPs
2630 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2631 {
2632 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2633 uint8_t *b = p;
2634 uint8_t flags = *p;
2635 uint16_t mtype;
2636
2637 if (n > l)
2638 {
2639 LOG(1, s, t, "Invalid length in AVP\n");
2640 STAT(tunnel_rx_errors);
2641 return;
2642 }
2643 p += n; // next
2644 l -= n;
2645 if (flags & 0x3C) // reserved bits, should be clear
2646 {
2647 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2648 fatal = flags;
2649 result = 2; // general error
2650 error = 3; // reserved field non-zero
2651 msg = 0;
2652 continue; // next
2653 }
2654 b += 2;
2655 if (*(uint16_t *) (b))
2656 {
2657 LOG(2, s, t, "Unknown AVP vendor %u\n", ntohs(*(uint16_t *) (b)));
2658 fatal = flags;
2659 result = 2; // general error
2660 error = 6; // generic vendor-specific error
2661 msg = "unsupported vendor-specific";
2662 continue; // next
2663 }
2664 b += 2;
2665 mtype = ntohs(*(uint16_t *) (b));
2666 b += 2;
2667 n -= 6;
2668
2669 if (flags & 0x40)
2670 {
2671 uint16_t orig_len;
2672
2673 // handle hidden AVPs
2674 if (!*config->l2tp_secret)
2675 {
2676 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2677 fatal = flags;
2678 result = 2; // general error
2679 error = 6; // generic vendor-specific error
2680 msg = "secret not specified";
2681 continue;
2682 }
2683 if (!session[s].random_vector_length)
2684 {
2685 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2686 fatal = flags;
2687 result = 2; // general error
2688 error = 6; // generic
2689 msg = "no random vector";
2690 continue;
2691 }
2692 if (n < 8)
2693 {
2694 LOG(2, s, t, "Short hidden AVP.\n");
2695 fatal = flags;
2696 result = 2; // general error
2697 error = 2; // length is wrong
2698 msg = 0;
2699 continue;
2700 }
2701
2702 // Unhide the AVP
2703 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2704
2705 orig_len = ntohs(*(uint16_t *) b);
2706 if (orig_len > n + 2)
2707 {
2708 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2709 orig_len, n);
2710
2711 fatal = flags;
2712 result = 2; // general error
2713 error = 2; // length is wrong
2714 msg = 0;
2715 continue;
2716 }
2717
2718 b += 2;
2719 n = orig_len;
2720 }
2721
2722 LOG(4, s, t, " AVP %u (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2723 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2724
2725 switch (mtype)
2726 {
2727 case 0: // message type
2728 message = ntohs(*(uint16_t *) b);
2729 mandatory = flags & 0x80;
2730 LOG(4, s, t, " Message type = %u (%s)\n", message, l2tp_code(message));
2731 break;
2732 case 1: // result code
2733 {
2734 uint16_t rescode = ntohs(*(uint16_t *) b);
2735 char const *resdesc = "(unknown)";
2736 char const *errdesc = NULL;
2737 int cause = 0;
2738
2739 if (message == 4)
2740 { /* StopCCN */
2741 resdesc = l2tp_stopccn_result_code(rescode);
2742 cause = TERM_LOST_SERVICE;
2743 }
2744 else if (message == 14)
2745 { /* CDN */
2746 resdesc = l2tp_cdn_result_code(rescode);
2747 if (rescode == 1)
2748 cause = TERM_LOST_CARRIER;
2749 else
2750 cause = TERM_ADMIN_RESET;
2751 }
2752
2753 LOG(4, s, t, " Result Code %u: %s\n", rescode, resdesc);
2754 if (n >= 4)
2755 {
2756 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2757 errdesc = l2tp_error_code(errcode);
2758 LOG(4, s, t, " Error Code %u: %s\n", errcode, errdesc);
2759 }
2760 if (n > 4)
2761 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2762
2763 if (cause && disc_cause_set < mtype) // take cause from attrib 46 in preference
2764 {
2765 disc_cause_set = mtype;
2766 disc_reason = errdesc ? errdesc : resdesc;
2767 disc_cause = cause;
2768 }
2769
2770 break;
2771 }
2772 break;
2773 case 2: // protocol version
2774 {
2775 version = ntohs(*(uint16_t *) (b));
2776 LOG(4, s, t, " Protocol version = %u\n", version);
2777 if (version && version != 0x0100)
2778 { // allow 0.0 and 1.0
2779 LOG(1, s, t, " Bad protocol version %04X\n", version);
2780 fatal = flags;
2781 result = 5; // unspported protocol version
2782 error = 0x0100; // supported version
2783 msg = 0;
2784 continue; // next
2785 }
2786 }
2787 break;
2788 case 3: // framing capabilities
2789 break;
2790 case 4: // bearer capabilities
2791 break;
2792 case 5: // tie breaker
2793 // We never open tunnels, so we don't care about tie breakers
2794 continue;
2795 case 6: // firmware revision
2796 break;
2797 case 7: // host name
2798 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2799 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2800 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2801 // TBA - to send to RADIUS
2802 break;
2803 case 8: // vendor name
2804 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2805 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2806 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2807 break;
2808 case 9: // assigned tunnel
2809 tunnel[t].far = ntohs(*(uint16_t *) (b));
2810 LOG(4, s, t, " Remote tunnel id = %u\n", tunnel[t].far);
2811 break;
2812 case 10: // rx window
2813 tunnel[t].window = ntohs(*(uint16_t *) (b));
2814 if (!tunnel[t].window)
2815 tunnel[t].window = 1; // window of 0 is silly
2816 LOG(4, s, t, " rx window = %u\n", tunnel[t].window);
2817 break;
2818 case 11: // Challenge
2819 {
2820 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2821 build_chap_response(b, 2, n, &chapresponse);
2822 }
2823 break;
2824 case 13: // Response
2825 if (tunnel[t].isremotelns)
2826 {
2827 chapresponse = calloc(17, 1);
2828 memcpy(chapresponse, b, (n < 17) ? n : 16);
2829 LOG(3, s, t, "received challenge response from REMOTE LNS\n");
2830 }
2831 else
2832 // Why did they send a response? We never challenge.
2833 LOG(2, s, t, " received unexpected challenge response\n");
2834 break;
2835
2836 case 14: // assigned session
2837 asession = session[s].far = ntohs(*(uint16_t *) (b));
2838 LOG(4, s, t, " assigned session = %u\n", asession);
2839 break;
2840 case 15: // call serial number
2841 LOG(4, s, t, " call serial number = %u\n", ntohl(*(uint32_t *)b));
2842 break;
2843 case 18: // bearer type
2844 LOG(4, s, t, " bearer type = %u\n", ntohl(*(uint32_t *)b));
2845 // TBA - for RADIUS
2846 break;
2847 case 19: // framing type
2848 LOG(4, s, t, " framing type = %u\n", ntohl(*(uint32_t *)b));
2849 // TBA
2850 break;
2851 case 21: // called number
2852 memset(called, 0, sizeof(called));
2853 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2854 LOG(4, s, t, " Called <%s>\n", called);
2855 break;
2856 case 22: // calling number
2857 memset(calling, 0, sizeof(calling));
2858 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2859 LOG(4, s, t, " Calling <%s>\n", calling);
2860 break;
2861 case 23: // subtype
2862 break;
2863 case 24: // tx connect speed
2864 if (n == 4)
2865 {
2866 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2867 }
2868 else
2869 {
2870 // AS5300s send connect speed as a string
2871 char tmp[30];
2872 memset(tmp, 0, sizeof(tmp));
2873 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2874 session[s].tx_connect_speed = atol(tmp);
2875 }
2876 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2877 break;
2878 case 38: // rx connect speed
2879 if (n == 4)
2880 {
2881 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2882 }
2883 else
2884 {
2885 // AS5300s send connect speed as a string
2886 char tmp[30];
2887 memset(tmp, 0, sizeof(tmp));
2888 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2889 session[s].rx_connect_speed = atol(tmp);
2890 }
2891 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2892 break;
2893 case 25: // Physical Channel ID
2894 {
2895 uint32_t tmp = ntohl(*(uint32_t *) b);
2896 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2897 break;
2898 }
2899 case 29: // Proxy Authentication Type
2900 {
2901 uint16_t atype = ntohs(*(uint16_t *)b);
2902 LOG(4, s, t, " Proxy Auth Type %u (%s)\n", atype, ppp_auth_type(atype));
2903 break;
2904 }
2905 case 30: // Proxy Authentication Name
2906 {
2907 char authname[64];
2908 memset(authname, 0, sizeof(authname));
2909 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2910 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2911 authname);
2912 break;
2913 }
2914 case 31: // Proxy Authentication Challenge
2915 {
2916 LOG(4, s, t, " Proxy Auth Challenge\n");
2917 break;
2918 }
2919 case 32: // Proxy Authentication ID
2920 {
2921 uint16_t authid = ntohs(*(uint16_t *)(b));
2922 LOG(4, s, t, " Proxy Auth ID (%u)\n", authid);
2923 break;
2924 }
2925 case 33: // Proxy Authentication Response
2926 LOG(4, s, t, " Proxy Auth Response\n");
2927 break;
2928 case 27: // last sent lcp
2929 { // find magic number
2930 uint8_t *p = b, *e = p + n;
2931 while (p + 1 < e && p[1] && p + p[1] <= e)
2932 {
2933 if (*p == 5 && p[1] == 6) // Magic-Number
2934 amagic = ntohl(*(uint32_t *) (p + 2));
2935 else if (*p == 7) // Protocol-Field-Compression
2936 aflags |= SESSION_PFC;
2937 else if (*p == 8) // Address-and-Control-Field-Compression
2938 aflags |= SESSION_ACFC;
2939 p += p[1];
2940 }
2941 }
2942 break;
2943 case 28: // last recv lcp confreq
2944 break;
2945 case 26: // Initial Received LCP CONFREQ
2946 break;
2947 case 39: // seq required - we control it as an LNS anyway...
2948 break;
2949 case 36: // Random Vector
2950 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2951 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2952 if (n > sizeof(session[s].random_vector))
2953 n = sizeof(session[s].random_vector);
2954 memcpy(session[s].random_vector, b, n);
2955 session[s].random_vector_length = n;
2956 break;
2957 case 46: // ppp disconnect cause
2958 if (n >= 5)
2959 {
2960 uint16_t code = ntohs(*(uint16_t *) b);
2961 uint16_t proto = ntohs(*(uint16_t *) (b + 2));
2962 uint8_t dir = *(b + 4);
2963
2964 LOG(4, s, t, " PPP disconnect cause "
2965 "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
2966 code, proto, dir, n - 5, b + 5);
2967
2968 disc_cause_set = mtype;
2969
2970 switch (code)
2971 {
2972 case 1: // admin disconnect
2973 disc_cause = TERM_ADMIN_RESET;
2974 disc_reason = "Administrative disconnect";
2975 break;
2976 case 3: // lcp terminate
2977 if (dir != 2) break; // 1=peer (LNS), 2=local (LAC)
2978 disc_cause = TERM_USER_REQUEST;
2979 disc_reason = "Normal disconnection";
2980 break;
2981 case 4: // compulsory encryption unavailable
2982 if (dir != 1) break; // 1=refused by peer, 2=local
2983 disc_cause = TERM_USER_ERROR;
2984 disc_reason = "Compulsory encryption refused";
2985 break;
2986 case 5: // lcp: fsm timeout
2987 disc_cause = TERM_PORT_ERROR;
2988 disc_reason = "LCP: FSM timeout";
2989 break;
2990 case 6: // lcp: no recognisable lcp packets received
2991 disc_cause = TERM_PORT_ERROR;
2992 disc_reason = "LCP: no recognisable LCP packets";
2993 break;
2994 case 7: // lcp: magic-no error (possibly looped back)
2995 disc_cause = TERM_PORT_ERROR;
2996 disc_reason = "LCP: magic-no error (possible loop)";
2997 break;
2998 case 8: // lcp: echo request timeout
2999 disc_cause = TERM_PORT_ERROR;
3000 disc_reason = "LCP: echo request timeout";
3001 break;
3002 case 13: // auth: fsm timeout
3003 disc_cause = TERM_SERVICE_UNAVAILABLE;
3004 disc_reason = "Authentication: FSM timeout";
3005 break;
3006 case 15: // auth: unacceptable auth protocol
3007 disc_cause = TERM_SERVICE_UNAVAILABLE;
3008 disc_reason = "Unacceptable authentication protocol";
3009 break;
3010 case 16: // auth: authentication failed
3011 disc_cause = TERM_SERVICE_UNAVAILABLE;
3012 disc_reason = "Authentication failed";
3013 break;
3014 case 17: // ncp: fsm timeout
3015 disc_cause = TERM_SERVICE_UNAVAILABLE;
3016 disc_reason = "NCP: FSM timeout";
3017 break;
3018 case 18: // ncp: no ncps available
3019 disc_cause = TERM_SERVICE_UNAVAILABLE;
3020 disc_reason = "NCP: no NCPs available";
3021 break;
3022 case 19: // ncp: failure to converge on acceptable address
3023 disc_cause = TERM_SERVICE_UNAVAILABLE;
3024 disc_reason = (dir == 1)
3025 ? "NCP: too many Configure-Naks received from peer"
3026 : "NCP: too many Configure-Naks sent to peer";
3027 break;
3028 case 20: // ncp: user not permitted to use any address
3029 disc_cause = TERM_SERVICE_UNAVAILABLE;
3030 disc_reason = (dir == 1)
3031 ? "NCP: local link address not acceptable to peer"
3032 : "NCP: remote link address not acceptable";
3033 break;
3034 }
3035 }
3036 break;
3037 default:
3038 {
3039 static char e[] = "unknown AVP 0xXXXX";
3040 LOG(2, s, t, " Unknown AVP type %u\n", mtype);
3041 fatal = flags;
3042 result = 2; // general error
3043 error = 8; // unknown mandatory AVP
3044 sprintf((msg = e) + 14, "%04x", mtype);
3045 continue; // next
3046 }
3047 }
3048 }
3049 // process message
3050 if (fatal & 0x80)
3051 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
3052 else
3053 switch (message)
3054 {
3055 case 1: // SCCRQ - Start Control Connection Request
3056 tunnel[t].state = TUNNELOPENING;
3057 LOG(3, s, t, "Received SCCRQ\n");
3058 if (main_quit != QUIT_SHUTDOWN)
3059 {
3060 LOG(3, s, t, "sending SCCRP\n");
3061 controlt *c = controlnew(2); // sending SCCRP
3062 control16(c, 2, version, 1); // protocol version
3063 control32(c, 3, 3, 1); // framing
3064 controls(c, 7, hostname, 1); // host name
3065 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
3066 control16(c, 9, t, 1); // assigned tunnel
3067 controladd(c, 0, t); // send the resply
3068 }
3069 else
3070 {
3071 tunnelshutdown(t, "Shutting down", 6, 0, 0);
3072 }
3073 break;
3074 case 2: // SCCRP
3075 tunnel[t].state = TUNNELOPEN;
3076 tunnel[t].lastrec = time_now;
3077 LOG(3, s, t, "Received SCCRP\n");
3078 if (main_quit != QUIT_SHUTDOWN)
3079 {
3080 if (tunnel[t].isremotelns && chapresponse)
3081 {
3082 hasht hash;
3083
3084 lac_calc_rlns_auth(t, 2, hash); // id = 2 (SCCRP)
3085 // check authenticator
3086 if (memcmp(hash, chapresponse, 16) == 0)
3087 {
3088 LOG(3, s, t, "sending SCCCN to REMOTE LNS\n");
3089 controlt *c = controlnew(3); // sending SCCCN
3090 controls(c, 7, hostname, 1); // host name
3091 controls(c, 8, Vendor_name, 1); // Vendor name
3092 control16(c, 2, version, 1); // protocol version
3093 control32(c, 3, 3, 1); // framing Capabilities
3094 control16(c, 9, t, 1); // assigned tunnel
3095 controladd(c, 0, t); // send
3096 }
3097 else
3098 {
3099 tunnelshutdown(t, "Bad chap response from REMOTE LNS", 4, 0, 0);
3100 }
3101 }
3102 }
3103 else
3104 {
3105 tunnelshutdown(t, "Shutting down", 6, 0, 0);
3106 }
3107 break;
3108 case 3: // SCCN
3109 LOG(3, s, t, "Received SCCN\n");
3110 tunnel[t].state = TUNNELOPEN;
3111 tunnel[t].lastrec = time_now;
3112 controlnull(t); // ack
3113 break;
3114 case 4: // StopCCN
3115 LOG(3, s, t, "Received StopCCN\n");
3116 controlnull(t); // ack
3117 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
3118 break;
3119 case 6: // HELLO
3120 LOG(3, s, t, "Received HELLO\n");
3121 controlnull(t); // simply ACK
3122 break;
3123 case 7: // OCRQ
3124 // TBA
3125 LOG(3, s, t, "Received OCRQ\n");
3126 break;
3127 case 8: // OCRO
3128 // TBA
3129 LOG(3, s, t, "Received OCRO\n");
3130 break;
3131 case 9: // OCCN
3132 // TBA
3133 LOG(3, s, t, "Received OCCN\n");
3134 break;
3135 case 10: // ICRQ
3136 LOG(3, s, t, "Received ICRQ\n");
3137 if (sessionfree && main_quit != QUIT_SHUTDOWN)
3138 {
3139 controlt *c = controlnew(11); // ICRP
3140
3141 LOG(3, s, t, "Sending ICRP\n");
3142
3143 s = sessionfree;
3144 sessionfree = session[s].next;
3145 memset(&session[s], 0, sizeof(session[s]));
3146
3147 if (s > config->cluster_highest_sessionid)
3148 config->cluster_highest_sessionid = s;
3149
3150 session[s].opened = time_now;
3151 session[s].tunnel = t;
3152 session[s].far = asession;
3153 session[s].last_packet = session[s].last_data = time_now;
3154 LOG(3, s, t, "New session (%u/%u)\n", tunnel[t].far, session[s].far);
3155 control16(c, 14, s, 1); // assigned session
3156 controladd(c, asession, t); // send the reply
3157
3158 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
3159 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
3160
3161 session[s].ppp.phase = Establish;
3162 session[s].ppp.lcp = Starting;
3163
3164 STAT(session_created);
3165 break;
3166 }
3167
3168 {
3169 controlt *c = controlnew(14); // CDN
3170 LOG(3, s, t, "Sending CDN\n");
3171 if (!sessionfree)
3172 {
3173 STAT(session_overflow);
3174 LOG(1, 0, t, "No free sessions\n");
3175 control16(c, 1, 4, 0); // temporary lack of resources
3176 }
3177 else
3178 control16(c, 1, 2, 7); // shutting down, try another
3179
3180 controladd(c, asession, t); // send the message
3181 }
3182 return;
3183 case 11: // ICRP
3184 LOG(3, s, t, "Received ICRP\n");
3185 if (session[s].forwardtosession)
3186 {
3187 controlt *c = controlnew(12); // ICCN
3188
3189 session[s].opened = time_now;
3190 session[s].tunnel = t;
3191 session[s].far = asession;
3192 session[s].last_packet = session[s].last_data = time_now;
3193
3194 control32(c, 19, 1, 1); // Framing Type
3195 control32(c, 24, 10000000, 1); // Tx Connect Speed
3196 controladd(c, asession, t); // send the message
3197 LOG(3, s, t, "Sending ICCN\n");
3198 }
3199 break;
3200 case 12: // ICCN
3201 LOG(3, s, t, "Received ICCN\n");
3202 if (amagic == 0) amagic = time_now;
3203 session[s].magic = amagic; // set magic number
3204 session[s].flags = aflags; // set flags received
3205 session[s].mru = PPPoE_MRU; // default
3206 controlnull(t); // ack
3207
3208 // start LCP
3209 sess_local[s].lcp_authtype = config->radius_authprefer;
3210 sess_local[s].ppp_mru = MRU;
3211
3212 // Set multilink options before sending initial LCP packet
3213 sess_local[s].mp_mrru = 1614;
3214 sess_local[s].mp_epdis = ntohl(config->iftun_n_address[tunnel[t].indexudp] ? config->iftun_n_address[tunnel[t].indexudp] : my_address);
3215
3216 sendlcp(s, t);
3217 change_state(s, lcp, RequestSent);
3218 break;
3219
3220 case 14: // CDN
3221 LOG(3, s, t, "Received CDN\n");
3222 controlnull(t); // ack
3223 sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
3224 break;
3225 case 0xFFFF:
3226 LOG(1, s, t, "Missing message type\n");
3227 break;
3228 default:
3229 STAT(tunnel_rx_errors);
3230 if (mandatory)
3231 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
3232 else
3233 LOG(1, s, t, "Unknown message type %u\n", message);
3234 break;
3235 }
3236 if (chapresponse) free(chapresponse);
3237 cluster_send_tunnel(t);
3238 }
3239 else
3240 {
3241 LOG(4, s, t, " Got a ZLB ack\n");
3242 }
3243 }
3244 else
3245 { // data
3246 uint16_t proto;
3247
3248 LOG_HEX(5, "Receive Tunnel Data", p, l);
3249 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
3250 { // HDLC address header, discard
3251 p += 2;
3252 l -= 2;
3253 }
3254 if (l < 2)
3255 {
3256 LOG(1, s, t, "Short ppp length %d\n", l);
3257 STAT(tunnel_rx_errors);
3258 return;
3259 }
3260 if (*p & 1)
3261 {
3262 proto = *p++;
3263 l--;
3264 }
3265 else
3266 {
3267 proto = ntohs(*(uint16_t *) p);
3268 p += 2;
3269 l -= 2;
3270 }
3271
3272 if (session[s].forwardtosession)
3273 {
3274 LOG(5, s, t, "Forwarding data session to session %u\n", session[s].forwardtosession);
3275 // Forward to LAC/BAS or Remote LNS session
3276 lac_session_forward(buf, len, s, proto, addr->sin_addr.s_addr, addr->sin_port, indexudpfd);
3277 return;
3278 }
3279 else if (config->auth_tunnel_change_addr_src)
3280 {
3281 if (tunnel[t].ip != ntohl(addr->sin_addr.s_addr) &&
3282 tunnel[t].port == ntohs(addr->sin_port))
3283 {
3284 // The remotes BAS are a clustered l2tpns server and the source IP has changed
3285 LOG(5, s, t, "The tunnel IP source (%s) has changed by new IP (%s)\n",
3286 fmtaddr(htonl(tunnel[t].ip), 0), fmtaddr(addr->sin_addr.s_addr, 0));
3287
3288 tunnel[t].ip = ntohl(addr->sin_addr.s_addr);
3289 }
3290 }
3291
3292 if (s && !session[s].opened) // Is something wrong??
3293 {
3294 if (!config->cluster_iam_master)
3295 {
3296 // Pass it off to the master to deal with..
3297 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd);
3298 return;
3299 }
3300
3301 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
3302 STAT(tunnel_rx_errors);
3303 return;
3304 }
3305
3306 if (proto == PPPPAP)
3307 {
3308 session[s].last_packet = time_now;
3309 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; }
3310 processpap(s, t, p, l);
3311 }
3312 else if (proto == PPPCHAP)
3313 {
3314 session[s].last_packet = time_now;
3315 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; }
3316 processchap(s, t, p, l);
3317 }
3318 else if (proto == PPPLCP)
3319 {
3320 session[s].last_packet = time_now;
3321 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; }
3322 processlcp(s, t, p, l);
3323 }
3324 else if (proto == PPPIPCP)
3325 {
3326 session[s].last_packet = time_now;
3327 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; }
3328 processipcp(s, t, p, l);
3329 }
3330 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
3331 {
3332 session[s].last_packet = time_now;
3333 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; }
3334 processipv6cp(s, t, p, l);
3335 }
3336 else if (proto == PPPCCP)
3337 {
3338 session[s].last_packet = time_now;
3339 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; }
3340 processccp(s, t, p, l);
3341 }
3342 else if (proto == PPPIP)
3343 {
3344 if (session[s].die)
3345 {
3346 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
3347 return; // closing session, PPP not processed
3348 }
3349
3350 session[s].last_packet = session[s].last_data = time_now;
3351 if (session[s].walled_garden && !config->cluster_iam_master)
3352 {
3353 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd);
3354 return;
3355 }
3356
3357 processipin(s, t, p, l);
3358 }
3359 else if (proto == PPPMP)
3360 {
3361 if (session[s].die)
3362 {
3363 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
3364 return; // closing session, PPP not processed
3365 }
3366
3367 session[s].last_packet = session[s].last_data = time_now;
3368 if (!config->cluster_iam_master)
3369 {
3370 // The fragments reconstruction is managed by the Master.
3371 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd);
3372 return;
3373 }
3374
3375 processmpin(s, t, p, l);
3376 }
3377 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
3378 {
3379 if (session[s].die)
3380 {
3381 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
3382 return; // closing session, PPP not processed
3383 }
3384
3385 session[s].last_packet = session[s].last_data = time_now;
3386 if (session[s].walled_garden && !config->cluster_iam_master)
3387 {
3388 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd);
3389 return;
3390 }
3391
3392 processipv6in(s, t, p, l);
3393 }
3394 else if (session[s].ppp.lcp == Opened)
3395 {
3396 session[s].last_packet = time_now;
3397 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port, indexudpfd); return; }
3398 protoreject(s, t, p, l, proto);
3399 }
3400 else
3401 {
3402 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
3403 proto, ppp_state(session[s].ppp.lcp));
3404 }
3405 }
3406 }
3407
3408 // read and process packet on tun
3409 // (i.e. this routine writes to buf[-8]).
3410 static void processtun(uint8_t * buf, int len)
3411 {
3412 LOG_HEX(5, "Receive TUN Data", buf, len);
3413 STAT(tun_rx_packets);
3414 INC_STAT(tun_rx_bytes, len);
3415
3416 CSTAT(processtun);
3417
3418 eth_rx_pkt++;
3419 eth_rx += len;
3420 if (len < 22)
3421 {
3422 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
3423 STAT(tun_rx_errors);
3424 return;
3425 }
3426
3427 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
3428 processipout(buf, len);
3429 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
3430 && config->ipv6_prefix.s6_addr[0])
3431 processipv6out(buf, len);
3432
3433 // Else discard.
3434 }
3435
3436 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
3437 // that we look at the whole of the tunnel, radius and session tables
3438 // every second
3439 static void regular_cleanups(double period)
3440 {
3441 // Next tunnel, radius and session to check for actions on.
3442 static tunnelidt t = 0;
3443 static int r = 0;
3444 static sessionidt s = 0;
3445
3446 int t_actions = 0;
3447 int r_actions = 0;
3448 int s_actions = 0;
3449
3450 int t_slice;
3451 int r_slice;
3452 int s_slice;
3453
3454 int i;
3455 int a;
3456
3457 // divide up tables into slices based on the last run
3458 t_slice = config->cluster_highest_tunnelid * period;
3459 r_slice = (MAXRADIUS - 1) * period;
3460 s_slice = config->cluster_highest_sessionid * period;
3461
3462 if (t_slice < 1)
3463 t_slice = 1;
3464 else if (t_slice > config->cluster_highest_tunnelid)
3465 t_slice = config->cluster_highest_tunnelid;
3466
3467 if (r_slice < 1)
3468 r_slice = 1;
3469 else if (r_slice > (MAXRADIUS - 1))
3470 r_slice = MAXRADIUS - 1;
3471
3472 if (s_slice < 1)
3473 s_slice = 1;
3474 else if (s_slice > config->cluster_highest_sessionid)
3475 s_slice = config->cluster_highest_sessionid;
3476
3477 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
3478
3479 for (i = 0; i < t_slice; i++)
3480 {
3481 t++;
3482 if (t > config->cluster_highest_tunnelid)
3483 t = 1;
3484
3485 if (t == TUNNEL_ID_PPPOE)
3486 continue;
3487
3488 // check for expired tunnels
3489 if (tunnel[t].die && tunnel[t].die <= TIME)
3490 {
3491 STAT(tunnel_timeout);
3492 tunnelkill(t, "Expired");
3493 t_actions++;
3494 continue;
3495 }
3496 // check for message resend
3497 if (tunnel[t].retry && tunnel[t].controlc)
3498 {
3499 // resend pending messages as timeout on reply
3500 if (tunnel[t].retry <= TIME)
3501 {
3502 controlt *c = tunnel[t].controls;
3503 uint16_t w = tunnel[t].window;
3504 tunnel[t].try++; // another try
3505 if (tunnel[t].try > 5)
3506 tunnelkill(t, "Timeout on control message"); // game over
3507 else
3508 while (c && w--)
3509 {
3510 tunnelsend(c->buf, c->length, t);
3511 c = c->next;
3512 }
3513
3514 t_actions++;
3515 }
3516 }
3517 // Send hello
3518 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
3519 {
3520 if (!config->disable_sending_hello)
3521 {
3522 controlt *c = controlnew(6); // sending HELLO
3523 controladd(c, 0, t); // send the message
3524 LOG(3, 0, t, "Sending HELLO message\n");
3525 t_actions++;
3526 }
3527 }
3528
3529 // Check for tunnel changes requested from the CLI
3530 if ((a = cli_tunnel_actions[t].action))
3531 {
3532 cli_tunnel_actions[t].action = 0;
3533 if (a & CLI_TUN_KILL)
3534 {
3535 LOG(2, 0, t, "Dropping tunnel by CLI\n");
3536 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
3537 t_actions++;
3538 }
3539 }
3540 }
3541
3542 for (i = 0; i < r_slice; i++)
3543 {
3544 r++;
3545 if (r >= MAXRADIUS)
3546 r = 1;
3547
3548 if (!radius[r].state)
3549 continue;
3550
3551 if (radius[r].retry <= TIME)
3552 {
3553 radiusretry(r);
3554 r_actions++;
3555 }
3556 }
3557
3558 for (i = 0; i < s_slice; i++)
3559 {
3560 s++;
3561 if (s > config->cluster_highest_sessionid)
3562 s = 1;
3563
3564 if (!session[s].opened) // Session isn't in use
3565 continue;
3566
3567 // check for expired sessions
3568 if (session[s].die)
3569 {
3570 if (session[s].die <= TIME)
3571 {
3572 sessionkill(s, "Expired");
3573 s_actions++;
3574 }
3575 continue;
3576 }
3577
3578 // PPP timeouts
3579 if (sess_local[s].lcp.restart <= time_now)
3580 {
3581 int next_state = session[s].ppp.lcp;
3582 switch (session[s].ppp.lcp)
3583 {
3584 case RequestSent:
3585 case AckReceived:
3586 next_state = RequestSent;
3587
3588 case AckSent:
3589 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
3590 {
3591 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
3592 sendlcp(s, session[s].tunnel);
3593 change_state(s, lcp, next_state);
3594 }
3595 else
3596 {
3597 sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3598 STAT(session_timeout);
3599 }
3600
3601 s_actions++;
3602 }
3603
3604 if (session[s].die)
3605 continue;
3606 }
3607
3608 if (sess_local[s].ipcp.restart <= time_now)
3609 {
3610 int next_state = session[s].ppp.ipcp;
3611 switch (session[s].ppp.ipcp)
3612 {
3613 case RequestSent:
3614 case AckReceived:
3615 next_state = RequestSent;
3616
3617 case AckSent:
3618 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
3619 {
3620 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
3621 sendipcp(s, session[s].tunnel);
3622 change_state(s, ipcp, next_state);
3623 }
3624 else
3625 {
3626 sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3627 STAT(session_timeout);
3628 }
3629
3630 s_actions++;
3631 }
3632
3633 if (session[s].die)
3634 continue;
3635 }
3636
3637 if (sess_local[s].ipv6cp.restart <= time_now)
3638 {
3639 int next_state = session[s].ppp.ipv6cp;
3640 switch (session[s].ppp.ipv6cp)
3641 {
3642 case RequestSent:
3643 case AckReceived:
3644 next_state = RequestSent;
3645
3646 case AckSent:
3647 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
3648 {
3649 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
3650 sendipv6cp(s, session[s].tunnel);
3651 change_state(s, ipv6cp, next_state);
3652 }
3653 else
3654 {
3655 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
3656 change_state(s, ipv6cp, Stopped);
3657 }
3658
3659 s_actions++;
3660 }
3661 }
3662
3663 if (sess_local[s].ccp.restart <= time_now)
3664 {
3665 int next_state = session[s].ppp.ccp;
3666 switch (session[s].ppp.ccp)
3667 {
3668 case RequestSent:
3669 case AckReceived:
3670 next_state = RequestSent;
3671
3672 case AckSent:
3673 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
3674 {
3675 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
3676 sendccp(s, session[s].tunnel);
3677 change_state(s, ccp, next_state);
3678 }
3679 else
3680 {
3681 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
3682 change_state(s, ccp, Stopped);
3683 }
3684
3685 s_actions++;
3686 }
3687 }
3688
3689 // Drop sessions who have not responded within IDLE_ECHO_TIMEOUT seconds
3690 if (session[s].last_packet && (time_now - session[s].last_packet >= config->idle_echo_timeout))
3691 {
3692 sessionshutdown(s, "No response to LCP ECHO requests.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3693 STAT(session_timeout);
3694 s_actions++;
3695 continue;
3696 }
3697
3698 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
3699 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= config->echo_timeout) &&
3700 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
3701 {
3702 uint8_t b[MAXETHER];
3703
3704 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP, 1, 0, 0);
3705 if (!q) continue;
3706
3707 *q = EchoReq;
3708 *(uint8_t *)(q + 1) = (time_now % 255); // ID
3709 *(uint16_t *)(q + 2) = htons(8); // Length
3710 *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
3711
3712 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
3713 (int)(time_now - session[s].last_packet));
3714
3715 tunnelsend(b, (q - b) + 8, session[s].tunnel); // send it
3716 sess_local[s].last_echo = time_now;
3717 s_actions++;
3718 }
3719
3720 // Drop sessions who have reached session_timeout seconds
3721 if (session[s].session_timeout)
3722 {
3723 bundleidt bid = session[s].bundle;
3724 if (bid)
3725 {
3726 if (time_now - bundle[bid].last_check >= 1)
3727 {
3728 bundle[bid].online_time += (time_now - bundle[bid].last_check) * bundle[bid].num_of_links;
3729 bundle[bid].last_check = time_now;
3730 if (bundle[bid].online_time >= session[s].session_timeout)
3731 {
3732 int ses;
3733 for (ses = bundle[bid].num_of_links - 1; ses >= 0; ses--)
3734 {
3735 sessionshutdown(bundle[bid].members[ses], "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3736 s_actions++;
3737 continue;
3738 }
3739 }
3740 }
3741 }
3742 else if (time_now - session[s].opened >= session[s].session_timeout)
3743 {
3744 sessionshutdown(s, "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3745 s_actions++;
3746 continue;
3747 }
3748 }
3749
3750 // Drop sessions who have reached idle_timeout seconds
3751 if (session[s].last_data && session[s].idle_timeout && (time_now - session[s].last_data >= session[s].idle_timeout))
3752 {
3753 sessionshutdown(s, "Idle Timeout Reached", CDN_ADMIN_DISC, TERM_IDLE_TIMEOUT);
3754 STAT(session_timeout);
3755 s_actions++;
3756 continue;
3757 }
3758
3759 // Check for actions requested from the CLI
3760 if ((a = cli_session_actions[s].action))
3761 {
3762 int send = 0;
3763
3764 cli_session_actions[s].action = 0;
3765 if (a & CLI_SESS_KILL)
3766 {
3767 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
3768 sessionshutdown(s, "Requested by administrator.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
3769 a = 0; // dead, no need to check for other actions
3770 s_actions++;
3771 }
3772
3773 if (a & CLI_SESS_NOSNOOP)
3774 {
3775 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
3776 session[s].snoop_ip = 0;
3777 session[s].snoop_port = 0;
3778 s_actions++;
3779 send++;
3780 }
3781 else if (a & CLI_SESS_SNOOP)
3782 {
3783 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%u)\n",
3784 fmtaddr(cli_session_actions[s].snoop_ip, 0),
3785 cli_session_actions[s].snoop_port);
3786
3787 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
3788 session[s].snoop_port = cli_session_actions[s].snoop_port;
3789 s_actions++;
3790 send++;
3791 }
3792
3793 if (a & CLI_SESS_NOTHROTTLE)
3794 {
3795 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
3796 throttle_session(s, 0, 0);
3797 s_actions++;
3798 send++;
3799 }
3800 else if (a & CLI_SESS_THROTTLE)
3801 {
3802 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
3803 cli_session_actions[s].throttle_in,
3804 cli_session_actions[s].throttle_out);
3805
3806 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
3807 s_actions++;
3808 send++;
3809 }
3810
3811 if (a & CLI_SESS_NOFILTER)
3812 {
3813 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3814 filter_session(s, 0, 0);
3815 s_actions++;
3816 send++;
3817 }
3818 else if (a & CLI_SESS_FILTER)
3819 {
3820 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3821 cli_session_actions[s].filter_in,
3822 cli_session_actions[s].filter_out);
3823
3824 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3825 s_actions++;
3826 send++;
3827 }
3828
3829 if (send)
3830 cluster_send_session(s);
3831 }
3832
3833 // RADIUS interim accounting
3834 if (config->radius_accounting && config->radius_interim > 0
3835 && session[s].ip && !session[s].walled_garden
3836 && !sess_local[s].radius // RADIUS already in progress
3837 && time_now - sess_local[s].last_interim >= config->radius_interim
3838 && session[s].flags & SESSION_STARTED)
3839 {
3840 int rad = radiusnew(s);
3841 if (!rad)
3842 {
3843 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3844 STAT(radius_overflow);
3845 continue;
3846 }
3847
3848 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3849 session[s].user, session[s].unique_id);
3850
3851 radiussend(rad, RADIUSINTERIM);
3852 sess_local[s].last_interim = time_now;
3853 s_actions++;
3854 }
3855 }
3856
3857 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3858 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3859 }
3860
3861 //
3862 // Are we in the middle of a tunnel update, or radius
3863 // requests??
3864 //
3865 static int still_busy(void)
3866 {
3867 int i;
3868 static clockt last_talked = 0;
3869 static clockt start_busy_wait = 0;
3870
3871 #ifdef BGP
3872 static time_t stopped_bgp = 0;
3873 if (bgp_configured)
3874 {
3875 if (!stopped_bgp)
3876 {
3877 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3878
3879 for (i = 0; i < BGP_NUM_PEERS; i++)
3880 if (bgp_peers[i].state == Established)
3881 bgp_stop(&bgp_peers[i]);
3882
3883 stopped_bgp = time_now;
3884
3885 if (!config->cluster_iam_master)
3886 {
3887 // we don't want to become master
3888 cluster_send_ping(0);
3889
3890 return 1;
3891 }
3892 }
3893
3894 if (!config->cluster_iam_master && time_now < (stopped_bgp + QUIT_DELAY))
3895 return 1;
3896 }
3897 #endif /* BGP */
3898
3899 if (!config->cluster_iam_master)
3900 return 0;
3901
3902 if (main_quit == QUIT_SHUTDOWN)
3903 {
3904 static int dropped = 0;
3905 if (!dropped)
3906 {
3907 int i;
3908
3909 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3910 for (i = 1; i < MAXTUNNEL; i++)
3911 if (tunnel[i].ip || tunnel[i].state)
3912 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3913
3914 dropped = 1;
3915 }
3916 }
3917
3918 if (start_busy_wait == 0)
3919 start_busy_wait = TIME;
3920
3921 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3922 {
3923 if (!tunnel[i].controlc)
3924 continue;
3925
3926 if (last_talked != TIME)
3927 {
3928 LOG(2, 0, 0, "Tunnel %u still has un-acked control messages.\n", i);
3929 last_talked = TIME;
3930 }
3931 return 1;
3932 }
3933
3934 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3935 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3936 {
3937 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3938 return 0;
3939 }
3940
3941 for (i = 1; i < MAXRADIUS; i++)
3942 {
3943 if (radius[i].state == RADIUSNULL)
3944 continue;
3945 if (radius[i].state == RADIUSWAIT)
3946 continue;
3947
3948 if (last_talked != TIME)
3949 {
3950 LOG(2, 0, 0, "Radius session %u is still busy (sid %u)\n", i, radius[i].session);
3951 last_talked = TIME;
3952 }
3953 return 1;
3954 }
3955
3956 return 0;
3957 }
3958
3959 #ifdef HAVE_EPOLL
3960 # include <sys/epoll.h>
3961 #else
3962 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3963 # include "fake_epoll.h"
3964 #endif
3965
3966 // the base set of fds polled: cli, cluster, tun, udp (MAX_UDPFD), control, dae, netlink, udplac, pppoedisc, pppoesess
3967 #define BASE_FDS (9 + MAX_UDPFD)
3968
3969 // additional polled fds
3970 #ifdef BGP
3971 # define EXTRA_FDS BGP_NUM_PEERS
3972 #else
3973 # define EXTRA_FDS 0
3974 #endif
3975
3976 // main loop - gets packets on tun or udp and processes them
3977 static void mainloop(void)
3978 {
3979 int i, j;
3980 uint8_t buf[65536];
3981 uint8_t *p = buf + 32; // for the hearder of the forwarded MPPP packet (see C_MPPP_FORWARD)
3982 // and the forwarded pppoe session
3983 int size_bufp = sizeof(buf) - 32;
3984 clockt next_cluster_ping = 0; // send initial ping immediately
3985 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3986 int maxevent = sizeof(events)/sizeof(*events);
3987
3988 if ((epollfd = epoll_create(maxevent)) < 0)
3989 {
3990 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3991 exit(1);
3992 }
3993
3994 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d, nlfd=%d , udplacfd=%d, pppoefd=%d, pppoesessfd=%d\n",
3995 clifd, cluster_sockfd, tunfd, udpfd[0], controlfd, daefd, nlfd, udplacfd, pppoediscfd, pppoesessfd);
3996
3997 /* setup our fds to poll for input */
3998 {
3999 static struct event_data d[BASE_FDS];
4000 struct epoll_event e;
4001
4002 e.events = EPOLLIN;
4003 i = 0;
4004
4005 if (clifd >= 0)
4006 {
4007 d[i].type = FD_TYPE_CLI;
4008 e.data.ptr = &d[i++];
4009 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
4010 }
4011
4012 d[i].type = FD_TYPE_CLUSTER;
4013 e.data.ptr = &d[i++];
4014 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
4015
4016 d[i].type = FD_TYPE_TUN;
4017 e.data.ptr = &d[i++];
4018 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
4019
4020 d[i].type = FD_TYPE_CONTROL;
4021 e.data.ptr = &d[i++];
4022 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
4023
4024 d[i].type = FD_TYPE_DAE;
4025 e.data.ptr = &d[i++];
4026 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
4027
4028 d[i].type = FD_TYPE_NETLINK;
4029 e.data.ptr = &d[i++];
4030 epoll_ctl(epollfd, EPOLL_CTL_ADD, nlfd, &e);
4031
4032 d[i].type = FD_TYPE_PPPOEDISC;
4033 e.data.ptr = &d[i++];
4034 epoll_ctl(epollfd, EPOLL_CTL_ADD, pppoediscfd, &e);
4035
4036 d[i].type = FD_TYPE_PPPOESESS;
4037 e.data.ptr = &d[i++];
4038 epoll_ctl(epollfd, EPOLL_CTL_ADD, pppoesessfd, &e);
4039
4040 for (j = 0; j < config->nbudpfd; j++)
4041 {
4042 d[i].type = FD_TYPE_UDP;
4043 d[i].index = j;
4044 e.data.ptr = &d[i++];
4045 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd[j], &e);
4046 }
4047 }
4048
4049 #ifdef BGP
4050 signal(SIGPIPE, SIG_IGN);
4051 bgp_setup(config->as_number);
4052 if (config->bind_address)
4053 bgp_add_route(config->bind_address, 0xffffffff);
4054
4055 for (i = 0; i < BGP_NUM_PEERS; i++)
4056 {
4057 if (config->neighbour[i].name[0])
4058 bgp_start(&bgp_peers[i], config->neighbour[i].name,
4059 config->neighbour[i].as, config->neighbour[i].keepalive,
4060 config->neighbour[i].hold, config->neighbour[i].update_source,
4061 0); /* 0 = routing disabled */
4062 }
4063 #endif /* BGP */
4064
4065 while (!main_quit || still_busy())
4066 {
4067 int more = 0;
4068 int n;
4069
4070
4071 if (main_reload)
4072 {
4073 main_reload = 0;
4074 read_config_file();
4075 config->reload_config++;
4076 }
4077
4078 if (config->reload_config)
4079 {
4080 config->reload_config = 0;
4081 update_config();
4082 }
4083
4084 #ifdef BGP
4085 bgp_set_poll();
4086 #endif /* BGP */
4087
4088 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
4089 STAT(select_called);
4090
4091 TIME = now(NULL);
4092 if (n < 0)
4093 {
4094 if (errno == EINTR ||
4095 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
4096 continue;
4097
4098 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
4099 break; // exit
4100 }
4101
4102 if (n)
4103 {
4104 struct sockaddr_in addr;
4105 struct in_addr local;
4106 socklen_t alen;
4107 int c, s;
4108 int udp_ready[MAX_UDPFD + 1] = INIT_TABUDPVAR;
4109 int pppoesess_ready = 0;
4110 int pppoesess_pkts = 0;
4111 int tun_ready = 0;
4112 int cluster_ready = 0;
4113 int udp_pkts[MAX_UDPFD + 1] = INIT_TABUDPVAR;
4114 int tun_pkts = 0;
4115 int cluster_pkts = 0;
4116 #ifdef BGP
4117 uint32_t bgp_events[BGP_NUM_PEERS];
4118 memset(bgp_events, 0, sizeof(bgp_events));
4119 #endif /* BGP */
4120
4121 for (c = n, i = 0; i < c; i++)
4122 {
4123 struct event_data *d = events[i].data.ptr;
4124
4125 switch (d->type)
4126 {
4127 case FD_TYPE_CLI: // CLI connections
4128 {
4129 int cli;
4130
4131 alen = sizeof(addr);
4132 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
4133 {
4134 cli_do(cli);
4135 close(cli);
4136 }
4137 else
4138 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
4139
4140 n--;
4141 break;
4142 }
4143
4144 // these are handled below, with multiple interleaved reads
4145 case FD_TYPE_CLUSTER: cluster_ready++; break;
4146 case FD_TYPE_TUN: tun_ready++; break;
4147 case FD_TYPE_UDP: udp_ready[d->index]++; break;
4148 case FD_TYPE_PPPOESESS: pppoesess_ready++; break;
4149
4150 case FD_TYPE_PPPOEDISC: // pppoe discovery
4151 s = read(pppoediscfd, p, size_bufp);
4152 if (s > 0) process_pppoe_disc(p, s);
4153 n--;
4154 break;
4155
4156 case FD_TYPE_CONTROL: // nsctl commands
4157 alen = sizeof(addr);
4158 s = recvfromto(controlfd, p, size_bufp, MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
4159 if (s > 0) processcontrol(p, s, &addr, alen, &local);
4160 n--;
4161 break;
4162
4163 case FD_TYPE_DAE: // DAE requests
4164 alen = sizeof(addr);
4165 s = recvfromto(daefd, p, size_bufp, MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
4166 if (s > 0) processdae(p, s, &addr, alen, &local);
4167 n--;
4168 break;
4169
4170 case FD_TYPE_RADIUS: // RADIUS response
4171 alen = sizeof(addr);
4172 s = recvfrom(radfds[d->index], p, size_bufp, MSG_WAITALL, (struct sockaddr *) &addr, &alen);
4173 if (s >= 0 && config->cluster_iam_master)
4174 {
4175 if (addr.sin_addr.s_addr == config->radiusserver[0] ||
4176 addr.sin_addr.s_addr == config->radiusserver[1])
4177 processrad(p, s, d->index);
4178 else
4179 LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
4180 fmtaddr(addr.sin_addr.s_addr, 0));
4181 }
4182
4183 n--;
4184 break;
4185
4186 #ifdef BGP
4187 case FD_TYPE_BGP:
4188 bgp_events[d->index] = events[i].events;
4189 n--;
4190 break;
4191 #endif /* BGP */
4192
4193 case FD_TYPE_NETLINK:
4194 {
4195 struct nlmsghdr *nh = (struct nlmsghdr *)p;
4196 s = netlink_recv(p, size_bufp);
4197 if (nh->nlmsg_type == NLMSG_ERROR)
4198 {
4199 struct nlmsgerr *errmsg = NLMSG_DATA(nh);
4200 if (errmsg->error)
4201 {
4202 if (errmsg->msg.nlmsg_seq < min_initok_nlseqnum)
4203 {
4204 LOG(0, 0, 0, "Got a fatal netlink error (while %s): %s\n", tun_nl_phase_msg[nh->nlmsg_seq], strerror(-errmsg->error));
4205 exit(1);
4206 }
4207 else
4208 LOG(0, 0, 0, "Got a netlink error: %s\n", strerror(-errmsg->error));
4209 }
4210 // else it's a ack
4211 }
4212 else
4213 LOG(1, 0, 0, "Got a unknown netlink message: type %d seq %d flags %d\n", nh->nlmsg_type, nh->nlmsg_seq, nh->nlmsg_flags);
4214 n--;
4215 break;
4216 }
4217
4218 default:
4219 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
4220 }
4221 }
4222
4223 #ifdef BGP
4224 bgp_process(bgp_events);
4225 #endif /* BGP */
4226
4227 for (c = 0; n && c < config->multi_read_count; c++)
4228 {
4229 for (j = 0; j < config->nbudpfd; j++)
4230 {
4231 // L2TP and L2TP REMOTE LNS
4232 if (udp_ready[j])
4233 {
4234 alen = sizeof(addr);
4235 if ((s = recvfrom(udpfd[j], p, size_bufp, 0, (void *) &addr, &alen)) > 0)
4236 {
4237 processudp(p, s, &addr, j);
4238 udp_pkts[j]++;
4239 }
4240 else
4241 {
4242 udp_ready[j] = 0;
4243 n--;
4244 }
4245 }
4246 }
4247
4248 // incoming IP
4249 if (tun_ready)
4250 {
4251 if ((s = read(tunfd, p, size_bufp)) > 0)
4252 {
4253 processtun(p, s);
4254 tun_pkts++;
4255 }
4256 else
4257 {
4258 tun_ready = 0;
4259 n--;
4260 }
4261 }
4262
4263 // pppoe session
4264 if (pppoesess_ready)
4265 {
4266 if ((s = read(pppoesessfd, p, size_bufp)) > 0)
4267 {
4268 process_pppoe_sess(p, s);
4269 pppoesess_pkts++;
4270 }
4271 else
4272 {
4273 pppoesess_ready = 0;
4274 n--;
4275 }
4276 }
4277
4278 // cluster
4279 if (cluster_ready)
4280 {
4281 alen = sizeof(addr);
4282 if ((s = recvfrom(cluster_sockfd, p, size_bufp, MSG_WAITALL, (void *) &addr, &alen)) > 0)
4283 {
4284 processcluster(p, s, addr.sin_addr.s_addr);
4285 cluster_pkts++;
4286 }
4287 else
4288 {
4289 cluster_ready = 0;
4290 n--;
4291 }
4292 }
4293 }
4294
4295 if (udp_pkts[0] > 1 || tun_pkts > 1 || cluster_pkts > 1)
4296 STAT(multi_read_used);
4297
4298 if (c >= config->multi_read_count)
4299 {
4300 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun %d cluster and %d pppoe packets\n",
4301 config->multi_read_count, udp_pkts[0], tun_pkts, cluster_pkts, pppoesess_pkts);
4302 STAT(multi_read_exceeded);
4303 more++;
4304 }
4305 }
4306 #ifdef BGP
4307 else
4308 /* no event received, but timers could still have expired */
4309 bgp_process_peers_timers();
4310 #endif /* BGP */
4311
4312 if (time_changed)
4313 {
4314 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
4315
4316 // Log current traffic stats
4317 snprintf(config->bandwidth, sizeof(config->bandwidth),
4318 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4319 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
4320 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
4321 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
4322
4323 udp_tx = udp_rx = 0;
4324 udp_rx_pkt = eth_rx_pkt = 0;
4325 eth_tx = eth_rx = 0;
4326 time_changed = 0;
4327
4328 if (config->dump_speed)
4329 printf("%s\n", config->bandwidth);
4330
4331 // Update the internal time counter
4332 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4333
4334 {
4335 // Run timer hooks
4336 struct param_timer p = { time_now };
4337 run_plugins(PLUGIN_TIMER, &p);
4338 }
4339 }
4340
4341 // Runs on every machine (master and slaves).
4342 if (next_cluster_ping <= TIME)
4343 {
4344 // Check to see which of the cluster is still alive..
4345
4346 cluster_send_ping(basetime); // Only does anything if we're a slave
4347 cluster_check_master(); // ditto.
4348
4349 cluster_heartbeat(); // Only does anything if we're a master.
4350 cluster_check_slaves(); // ditto.
4351
4352 master_update_counts(); // If we're a slave, send our byte counters to our master.
4353
4354 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
4355 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
4356 else
4357 next_cluster_ping = TIME + config->cluster_hb_interval;
4358 }
4359
4360 if (!config->cluster_iam_master)
4361 continue;
4362
4363 // Run token bucket filtering queue..
4364 // Only run it every 1/10th of a second.
4365 {
4366 static clockt last_run = 0;
4367 if (last_run != TIME)
4368 {
4369 last_run = TIME;
4370 tbf_run_timer();
4371 }
4372 }
4373
4374 // Handle timeouts, retries etc.
4375 {
4376 static double last_clean = 0;
4377 double this_clean;
4378 double diff;
4379
4380 TIME = now(&this_clean);
4381 diff = this_clean - last_clean;
4382
4383 // Run during idle time (after we've handled
4384 // all incoming packets) or every 1/10th sec
4385 if (!more || diff > 0.1)
4386 {
4387 regular_cleanups(diff);
4388 last_clean = this_clean;
4389 }
4390 }
4391
4392 if (*config->accounting_dir)
4393 {
4394 static clockt next_acct = 0;
4395 static clockt next_shut_acct = 0;
4396
4397 if (next_acct <= TIME)
4398 {
4399 // Dump accounting data
4400 next_acct = TIME + ACCT_TIME;
4401 next_shut_acct = TIME + ACCT_SHUT_TIME;
4402 dump_acct_info(1);
4403 }
4404 else if (next_shut_acct <= TIME)
4405 {
4406 // Dump accounting data for shutdown sessions
4407 next_shut_acct = TIME + ACCT_SHUT_TIME;
4408 if (shut_acct_n)
4409 dump_acct_info(0);
4410 }
4411 }
4412 }
4413
4414 // Are we the master and shutting down??
4415 if (config->cluster_iam_master)
4416 cluster_heartbeat(); // Flush any queued changes..
4417
4418 // Ok. Notify everyone we're shutting down. If we're
4419 // the master, this will force an election.
4420 cluster_send_ping(0);
4421
4422 //
4423 // Important!!! We MUST not process any packets past this point!
4424 LOG(1, 0, 0, "Shutdown complete\n");
4425 }
4426
4427 static void stripdomain(char *host)
4428 {
4429 char *p;
4430
4431 if ((p = strchr(host, '.')))
4432 {
4433 char *domain = 0;
4434 char _domain[1024];
4435
4436 // strip off domain
4437 FILE *resolv = fopen("/etc/resolv.conf", "r");
4438 if (resolv)
4439 {
4440 char buf[1024];
4441 char *b;
4442
4443 while (fgets(buf, sizeof(buf), resolv))
4444 {
4445 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
4446 continue;
4447
4448 if (!isspace(buf[6]))
4449 continue;
4450
4451 b = buf + 7;
4452 while (isspace(*b)) b++;
4453
4454 if (*b)
4455 {
4456 char *d = b;
4457 while (*b && !isspace(*b)) b++;
4458 *b = 0;
4459 if (buf[0] == 'd') // domain is canonical
4460 {
4461 domain = d;
4462 break;
4463 }
4464
4465 // first search line
4466 if (!domain)
4467 {
4468 // hold, may be subsequent domain line
4469 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
4470 domain = _domain;
4471 }
4472 }
4473 }
4474
4475 fclose(resolv);
4476 }
4477
4478 if (domain)
4479 {
4480 int hl = strlen(host);
4481 int dl = strlen(domain);
4482 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
4483 host[hl -dl - 1] = 0;
4484 }
4485 else
4486 {
4487 *p = 0; // everything after first dot
4488 }
4489 }
4490 }
4491
4492 // Init data structures
4493 static void initdata(int optdebug, char *optconfig)
4494 {
4495 int i;
4496
4497 if (!(config = shared_malloc(sizeof(configt))))
4498 {
4499 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
4500 exit(1);
4501 }
4502
4503 memset(config, 0, sizeof(configt));
4504 time(&config->start_time);
4505 strncpy(config->config_file, optconfig, strlen(optconfig));
4506 config->debug = optdebug;
4507 config->num_tbfs = MAXTBFS;
4508 config->rl_rate = 28; // 28kbps
4509 config->cluster_mcast_ttl = 1;
4510 config->cluster_master_min_adv = 1;
4511 config->ppp_restart_time = 3;
4512 config->ppp_max_configure = 10;
4513 config->ppp_max_failure = 5;
4514 config->kill_timedout_sessions = 1;
4515 strcpy(config->random_device, RANDOMDEVICE);
4516 // Set default value echo_timeout and idle_echo_timeout
4517 config->echo_timeout = ECHO_TIMEOUT;
4518 config->idle_echo_timeout = IDLE_ECHO_TIMEOUT;
4519
4520 log_stream = stderr;
4521
4522 #ifdef RINGBUFFER
4523 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
4524 {
4525 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
4526 exit(1);
4527 }
4528 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
4529 #endif
4530
4531 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
4532 {
4533 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
4534 exit(1);
4535 }
4536 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
4537 {
4538 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
4539 exit(1);
4540 }
4541 if (!(bundle = shared_malloc(sizeof(bundlet) * MAXBUNDLE)))
4542 {
4543 LOG(0, 0, 0, "Error doing malloc for bundles: %s\n", strerror(errno));
4544 exit(1);
4545 }
4546 if (!(frag = shared_malloc(sizeof(fragmentationt) * MAXBUNDLE)))
4547 {
4548 LOG(0, 0, 0, "Error doing malloc for fragmentations: %s\n", strerror(errno));
4549 exit(1);
4550 }
4551 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
4552 {
4553 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
4554 exit(1);
4555 }
4556
4557 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
4558 {
4559 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
4560 exit(1);
4561 }
4562
4563 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
4564 {
4565 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
4566 exit(1);
4567 }
4568
4569 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
4570 {
4571 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
4572 exit(1);
4573 }
4574
4575 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
4576 {
4577 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
4578 exit(1);
4579 }
4580 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
4581
4582 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
4583 {
4584 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
4585 exit(1);
4586 }
4587 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
4588
4589 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
4590 {
4591 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
4592 exit(1);
4593 }
4594 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
4595
4596 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
4597 memset(bundle, 0, sizeof(bundlet) * MAXBUNDLE);
4598 memset(session, 0, sizeof(sessiont) * MAXSESSION);
4599 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
4600 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
4601
4602 // Put all the sessions on the free list marked as undefined.
4603 for (i = 1; i < MAXSESSION; i++)
4604 {
4605 session[i].next = i + 1;
4606 session[i].tunnel = T_UNDEF; // mark it as not filled in.
4607 }
4608 session[MAXSESSION - 1].next = 0;
4609 sessionfree = 1;
4610
4611 // Mark all the tunnels as undefined (waiting to be filled in by a download).
4612 for (i = 1; i < MAXTUNNEL; i++)
4613 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
4614
4615 for (i = 1; i < MAXBUNDLE; i++) {
4616 bundle[i].state = BUNDLEUNDEF;
4617 }
4618
4619 if (!*hostname)
4620 {
4621 // Grab my hostname unless it's been specified
4622 gethostname(hostname, sizeof(hostname));
4623 stripdomain(hostname);
4624 }
4625
4626 _statistics->start_time = _statistics->last_reset = time(NULL);
4627
4628 #ifdef BGP
4629 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
4630 {
4631 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
4632 exit(1);
4633 }
4634 #endif /* BGP */
4635
4636 lac_initremotelnsdata();
4637 }
4638
4639 static int assign_ip_address(sessionidt s)
4640 {
4641 uint32_t i;
4642 int best = -1;
4643 time_t best_time = time_now;
4644 char *u = session[s].user;
4645 char reuse = 0;
4646
4647
4648 CSTAT(assign_ip_address);
4649
4650 for (i = 1; i < ip_pool_size; i++)
4651 {
4652 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
4653 continue;
4654
4655 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
4656 {
4657 best = i;
4658 reuse = 1;
4659 break;
4660 }
4661
4662 if (ip_address_pool[i].last < best_time)
4663 {
4664 best = i;
4665 if (!(best_time = ip_address_pool[i].last))
4666 break; // never used, grab this one
4667 }
4668 }
4669
4670 if (best < 0)
4671 {
4672 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
4673 return 0;
4674 }
4675
4676 session[s].ip = ip_address_pool[best].address;
4677 session[s].ip_pool_index = best;
4678 ip_address_pool[best].assigned = 1;
4679 ip_address_pool[best].last = time_now;
4680 ip_address_pool[best].session = s;
4681 if (session[s].walled_garden)
4682 /* Don't track addresses of users in walled garden (note: this
4683 means that their address isn't "sticky" even if they get
4684 un-gardened). */
4685 ip_address_pool[best].user[0] = 0;
4686 else
4687 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
4688
4689 STAT(ip_allocated);
4690 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
4691 reuse ? "Reusing" : "Allocating", best);
4692
4693 return 1;
4694 }
4695
4696 static void free_ip_address(sessionidt s)
4697 {
4698 int i = session[s].ip_pool_index;
4699
4700
4701 CSTAT(free_ip_address);
4702
4703 if (!session[s].ip)
4704 return; // what the?
4705
4706 if (i < 0) // Is this actually part of the ip pool?
4707 i = 0;
4708
4709 STAT(ip_freed);
4710 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
4711 session[s].ip = 0;
4712 ip_address_pool[i].assigned = 0;
4713 ip_address_pool[i].session = 0;
4714 ip_address_pool[i].last = time_now;
4715 }
4716
4717 //
4718 // Fsck the address pool against the session table.
4719 // Normally only called when we become a master.
4720 //
4721 // This isn't perfect: We aren't keep tracking of which
4722 // users used to have an IP address.
4723 //
4724 void rebuild_address_pool(void)
4725 {
4726 int i;
4727
4728 //
4729 // Zero the IP pool allocation, and build
4730 // a map from IP address to pool index.
4731 for (i = 1; i < MAXIPPOOL; ++i)
4732 {
4733 ip_address_pool[i].assigned = 0;
4734 ip_address_pool[i].session = 0;
4735 if (!ip_address_pool[i].address)
4736 continue;
4737
4738 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
4739 }
4740
4741 for (i = 0; i < MAXSESSION; ++i)
4742 {
4743 int ipid;
4744 if (!(session[i].opened && session[i].ip))
4745 continue;
4746
4747 ipid = - lookup_ipmap(htonl(session[i].ip));
4748
4749 if (session[i].ip_pool_index < 0)
4750 {
4751 // Not allocated out of the pool.
4752 if (ipid < 1) // Not found in the pool either? good.
4753 continue;
4754
4755 LOG(0, i, 0, "Session %u has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
4756 i, fmtaddr(session[i].ip, 0), ipid);
4757
4758 // Fall through and process it as part of the pool.
4759 }
4760
4761
4762 if (ipid > MAXIPPOOL || ipid < 0)
4763 {
4764 LOG(0, i, 0, "Session %u has a pool IP that's not found in the pool! (%d)\n", i, ipid);
4765 ipid = -1;
4766 session[i].ip_pool_index = ipid;
4767 continue;
4768 }
4769
4770 ip_address_pool[ipid].assigned = 1;
4771 ip_address_pool[ipid].session = i;
4772 ip_address_pool[ipid].last = time_now;
4773 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
4774 session[i].ip_pool_index = ipid;
4775 cache_ipmap(session[i].ip, i); // Fix the ip map.
4776 }
4777 }
4778
4779 //
4780 // Fix the address pool to match a changed session.
4781 // (usually when the master sends us an update).
4782 static void fix_address_pool(int sid)
4783 {
4784 int ipid;
4785
4786 ipid = session[sid].ip_pool_index;
4787
4788 if (ipid > ip_pool_size)
4789 return; // Ignore it. rebuild_address_pool will fix it up.
4790
4791 if (ip_address_pool[ipid].address != session[sid].ip)
4792 return; // Just ignore it. rebuild_address_pool will take care of it.
4793
4794 ip_address_pool[ipid].assigned = 1;
4795 ip_address_pool[ipid].session = sid;
4796 ip_address_pool[ipid].last = time_now;
4797 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
4798 }
4799
4800 //
4801 // Add a block of addresses to the IP pool to hand out.
4802 //
4803 static void add_to_ip_pool(in_addr_t addr, int prefixlen)
4804 {
4805 int i;
4806 if (prefixlen == 0)
4807 prefixlen = 32; // Host route only.
4808
4809 addr &= 0xffffffff << (32 - prefixlen);
4810
4811 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
4812 return ;
4813
4814 for (i = addr ; i < addr+(1<<(32-prefixlen)); ++i)
4815 {
4816 if ((i & 0xff) == 0 || (i&0xff) == 255)
4817 continue; // Skip 0 and broadcast addresses.
4818
4819 ip_address_pool[ip_pool_size].address = i;
4820 ip_address_pool[ip_pool_size].assigned = 0;
4821 ++ip_pool_size;
4822 if (ip_pool_size >= MAXIPPOOL)
4823 {
4824 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
4825 return;
4826 }
4827 }
4828 }
4829
4830 // Initialize the IP address pool
4831 static void initippool()
4832 {
4833 FILE *f;
4834 char *p;
4835 char buf[4096];
4836 memset(ip_address_pool, 0, sizeof(ip_address_pool));
4837
4838 if (!(f = fopen(IPPOOLFILE, "r")))
4839 {
4840 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
4841 exit(1);
4842 }
4843
4844 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
4845 {
4846 char *pool = buf;
4847 buf[4095] = 0; // Force it to be zero terminated/
4848
4849 if (*buf == '#' || *buf == '\n')
4850 continue; // Skip comments / blank lines
4851 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
4852 if ((p = (char *)strchr(buf, ':')))
4853 {
4854 in_addr_t src;
4855 *p = '\0';
4856 src = inet_addr(buf);
4857 if (src == INADDR_NONE)
4858 {
4859 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
4860 exit(1);
4861 }
4862 // This entry is for a specific IP only
4863 if (src != config->bind_address)
4864 continue;
4865 *p = ':';
4866 pool = p+1;
4867 }
4868 if ((p = (char *)strchr(pool, '/')))
4869 {
4870 // It's a range
4871 int numbits = 0;
4872 in_addr_t start = 0;
4873
4874 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
4875 *p++ = 0;
4876 if (!*p || !(numbits = atoi(p)))
4877 {
4878 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
4879 continue;
4880 }
4881 start = ntohl(inet_addr(pool));
4882
4883 // Add a static route for this pool
4884 LOG(5, 0, 0, "Adding route for address pool %s/%d\n",
4885 fmtaddr(htonl(start), 0), numbits);
4886
4887 routeset(0, start, numbits, 0, 1);
4888
4889 add_to_ip_pool(start, numbits);
4890 }
4891 else
4892 {
4893 // It's a single ip address
4894 add_to_ip_pool(ntohl(inet_addr(pool)), 0);
4895 }
4896 }
4897 fclose(f);
4898 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
4899 }
4900
4901 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
4902 {
4903 struct sockaddr_in snoop_addr = {0};
4904 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
4905 return;
4906
4907 snoop_addr.sin_family = AF_INET;
4908 snoop_addr.sin_addr.s_addr = destination;
4909 snoop_addr.sin_port = ntohs(port);
4910
4911 LOG(5, 0, 0, "Snooping %d byte packet to %s:%u\n", size,
4912 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
4913 htons(snoop_addr.sin_port));
4914
4915 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
4916 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
4917
4918 STAT(packets_snooped);
4919 }
4920
4921 static int dump_session(FILE **f, sessiont *s)
4922 {
4923 if (!s->opened || (!s->ip && !s->forwardtosession) || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
4924 return 1;
4925
4926 if (!*f)
4927 {
4928 char filename[1024];
4929 char timestr[64];
4930 time_t now = time(NULL);
4931
4932 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4933 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4934
4935 if (!(*f = fopen(filename, "w")))
4936 {
4937 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4938 return 0;
4939 }
4940
4941 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4942 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4943 "# host: %s\n"
4944 "# endpoint: %s\n"
4945 "# time: %ld\n"
4946 "# uptime: %ld\n"
4947 "# format: username ip qos uptxoctets downrxoctets\n",
4948 hostname,
4949 fmtaddr(config->iftun_n_address[tunnel[s->tunnel].indexudp] ? config->iftun_n_address[tunnel[s->tunnel].indexudp] : my_address, 0),
4950 now,
4951 now - basetime);
4952 }
4953
4954 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4955 fprintf(*f, "%s %s %d %u %u\n",
4956 s->user, // username
4957 fmtaddr(htonl(s->ip), 0), // ip
4958 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4959 (uint32_t) s->cin_delta, // uptxoctets
4960 (uint32_t) s->cout_delta); // downrxoctets
4961
4962 s->cin_delta = s->cout_delta = 0;
4963
4964 return 1;
4965 }
4966
4967 static void dump_acct_info(int all)
4968 {
4969 int i;
4970 FILE *f = NULL;
4971
4972
4973 CSTAT(dump_acct_info);
4974
4975 if (shut_acct_n)
4976 {
4977 for (i = 0; i < shut_acct_n; i++)
4978 dump_session(&f, &shut_acct[i]);
4979
4980 shut_acct_n = 0;
4981 }
4982
4983 if (all)
4984 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4985 dump_session(&f, &session[i]);
4986
4987 if (f)
4988 fclose(f);
4989 }
4990
4991 // Main program
4992 int main(int argc, char *argv[])
4993 {
4994 int i;
4995 int optdebug = 0;
4996 char *optconfig = CONFIGFILE;
4997
4998 time(&basetime); // start clock
4999
5000 // scan args
5001 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
5002 {
5003 switch (i)
5004 {
5005 case 'd':
5006 if (fork()) exit(0);
5007 setsid();
5008 freopen("/dev/null", "r", stdin);
5009 freopen("/dev/null", "w", stdout);
5010 freopen("/dev/null", "w", stderr);
5011 break;
5012 case 'v':
5013 optdebug++;
5014 break;
5015 case 'c':
5016 optconfig = optarg;
5017 break;
5018 case 'h':
5019 snprintf(hostname, sizeof(hostname), "%s", optarg);
5020 break;
5021 default:
5022 printf("Args are:\n"
5023 "\t-d\t\tDetach from terminal\n"
5024 "\t-c <file>\tConfig file\n"
5025 "\t-h <hostname>\tForce hostname\n"
5026 "\t-v\t\tDebug\n");
5027
5028 return (0);
5029 break;
5030 }
5031 }
5032
5033 // Start the timer routine off
5034 time(&time_now);
5035 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
5036
5037 initplugins();
5038 initdata(optdebug, optconfig);
5039
5040 init_cli();
5041 read_config_file();
5042 /* set hostname /after/ having read the config file */
5043 if (*config->hostname)
5044 strcpy(hostname, config->hostname);
5045 cli_init_complete(hostname);
5046 update_config();
5047 init_tbf(config->num_tbfs);
5048
5049 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
5050 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005, 2006 Optus Internet Engineering\n");
5051 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
5052 {
5053 struct rlimit rlim;
5054 rlim.rlim_cur = RLIM_INFINITY;
5055 rlim.rlim_max = RLIM_INFINITY;
5056 // Remove the maximum core size
5057 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
5058 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
5059
5060 // Make core dumps go to /tmp
5061 chdir("/tmp");
5062 }
5063
5064 if (config->scheduler_fifo)
5065 {
5066 int ret;
5067 struct sched_param params = {0};
5068 params.sched_priority = 1;
5069
5070 if (get_nprocs() < 2)
5071 {
5072 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
5073 config->scheduler_fifo = 0;
5074 }
5075 else
5076 {
5077 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
5078 {
5079 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
5080 }
5081 else
5082 {
5083 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
5084 config->scheduler_fifo = 0;
5085 }
5086 }
5087 }
5088
5089 initnetlink();
5090
5091 /* Set up the cluster communications port. */
5092 if (cluster_init() < 0)
5093 exit(1);
5094
5095 inittun();
5096 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevicename);
5097
5098 if (*config->pppoe_if_to_bind)
5099 {
5100 init_pppoe();
5101 LOG(1, 0, 0, "Set up on pppoe interface %s\n", config->pppoe_if_to_bind);
5102 }
5103
5104 if (!config->nbmultiaddress)
5105 {
5106 config->bind_n_address[0] = config->bind_address;
5107 config->nbmultiaddress++;
5108 }
5109 config->nbudpfd = config->nbmultiaddress;
5110 for (i = 0; i < config->nbudpfd; i++)
5111 initudp(&udpfd[i], config->bind_n_address[i]);
5112 initlacudp();
5113 config->indexlacudpfd = config->nbudpfd;
5114 udpfd[config->indexlacudpfd] = udplacfd;
5115 config->nbudpfd++;
5116
5117 initcontrol();
5118 initdae();
5119
5120 // Intercept
5121 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
5122
5123 initrad();
5124 initippool();
5125
5126 // seed prng
5127 {
5128 unsigned seed = time_now ^ getpid();
5129 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
5130 srand(seed);
5131 }
5132
5133 signal(SIGHUP, sighup_handler);
5134 signal(SIGCHLD, sigchild_handler);
5135 signal(SIGTERM, shutdown_handler);
5136 signal(SIGINT, shutdown_handler);
5137 signal(SIGQUIT, shutdown_handler);
5138
5139 // Prevent us from getting paged out
5140 if (config->lock_pages)
5141 {
5142 if (!mlockall(MCL_CURRENT))
5143 LOG(1, 0, 0, "Locking pages into memory\n");
5144 else
5145 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
5146 }
5147
5148 mainloop();
5149
5150 /* remove plugins (so cleanup code gets run) */
5151 plugins_done();
5152
5153 // Remove the PID file if we wrote it
5154 if (config->wrote_pid && *config->pid_file == '/')
5155 unlink(config->pid_file);
5156
5157 /* kill CLI children */
5158 signal(SIGTERM, SIG_IGN);
5159 kill(0, SIGTERM);
5160 return 0;
5161 }
5162
5163 static void sighup_handler(int sig)
5164 {
5165 main_reload++;
5166 }
5167
5168 static void shutdown_handler(int sig)
5169 {
5170 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
5171 }
5172
5173 static void sigchild_handler(int sig)
5174 {
5175 while (waitpid(-1, NULL, WNOHANG) > 0)
5176 ;
5177 }
5178
5179 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
5180 {
5181 MD5_CTX ctx;
5182 *challenge_response = NULL;
5183
5184 if (!*config->l2tp_secret)
5185 {
5186 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
5187 return;
5188 }
5189
5190 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
5191
5192 *challenge_response = calloc(17, 1);
5193
5194 MD5_Init(&ctx);
5195 MD5_Update(&ctx, &id, 1);
5196 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5197 MD5_Update(&ctx, challenge, challenge_length);
5198 MD5_Final(*challenge_response, &ctx);
5199
5200 return;
5201 }
5202
5203 static int facility_value(char *name)
5204 {
5205 int i;
5206 for (i = 0; facilitynames[i].c_name; i++)
5207 {
5208 if (strcmp(facilitynames[i].c_name, name) == 0)
5209 return facilitynames[i].c_val;
5210 }
5211 return 0;
5212 }
5213
5214 static void update_config()
5215 {
5216 int i;
5217 char *p;
5218 static int timeout = 0;
5219 static int interval = 0;
5220
5221 // Update logging
5222 closelog();
5223 syslog_log = 0;
5224 if (log_stream)
5225 {
5226 if (log_stream != stderr)
5227 fclose(log_stream);
5228
5229 log_stream = NULL;
5230 }
5231
5232 if (*config->log_filename)
5233 {
5234 if (strstr(config->log_filename, "syslog:") == config->log_filename)
5235 {
5236 char *p = config->log_filename + 7;
5237 if (*p)
5238 {
5239 openlog("l2tpns", LOG_PID, facility_value(p));
5240 syslog_log = 1;
5241 }
5242 }
5243 else if (strchr(config->log_filename, '/') == config->log_filename)
5244 {
5245 if ((log_stream = fopen((char *)(config->log_filename), "a")))
5246 {
5247 fseek(log_stream, 0, SEEK_END);
5248 setbuf(log_stream, NULL);
5249 }
5250 else
5251 {
5252 log_stream = stderr;
5253 setbuf(log_stream, NULL);
5254 }
5255 }
5256 }
5257 else
5258 {
5259 log_stream = stderr;
5260 setbuf(log_stream, NULL);
5261 }
5262
5263 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
5264 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
5265
5266 if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
5267 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
5268 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
5269
5270 // reset MRU/MSS globals
5271 MRU = config->l2tp_mtu - L2TP_HDRS;
5272 if (MRU > PPPoE_MRU)
5273 MRU = PPPoE_MRU;
5274
5275 MSS = MRU - TCP_HDRS;
5276
5277 // Update radius
5278 config->numradiusservers = 0;
5279 for (i = 0; i < MAXRADSERVER; i++)
5280 if (config->radiusserver[i])
5281 {
5282 config->numradiusservers++;
5283 // Set radius port: if not set, take the port from the
5284 // first radius server. For the first radius server,
5285 // take the #defined default value from l2tpns.h
5286
5287 // test twice, In case someone works with
5288 // a secondary radius server without defining
5289 // a primary one, this will work even then.
5290 if (i > 0 && !config->radiusport[i])
5291 config->radiusport[i] = config->radiusport[i-1];
5292 if (!config->radiusport[i])
5293 config->radiusport[i] = RADPORT;
5294 }
5295
5296 if (!config->numradiusservers)
5297 LOG(0, 0, 0, "No RADIUS servers defined!\n");
5298
5299 // parse radius_authtypes_s
5300 config->radius_authtypes = config->radius_authprefer = 0;
5301 p = config->radius_authtypes_s;
5302 while (p && *p)
5303 {
5304 char *s = strpbrk(p, " \t,");
5305 int type = 0;
5306
5307 if (s)
5308 {
5309 *s++ = 0;
5310 while (*s == ' ' || *s == '\t')
5311 s++;
5312
5313 if (!*s)
5314 s = 0;
5315 }
5316
5317 if (!strncasecmp("chap", p, strlen(p)))
5318 type = AUTHCHAP;
5319 else if (!strncasecmp("pap", p, strlen(p)))
5320 type = AUTHPAP;
5321 else
5322 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
5323
5324 config->radius_authtypes |= type;
5325 if (!config->radius_authprefer)
5326 config->radius_authprefer = type;
5327
5328 p = s;
5329 }
5330
5331 if (!config->radius_authtypes)
5332 {
5333 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
5334 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
5335 }
5336
5337 // normalise radius_authtypes_s
5338 if (config->radius_authprefer == AUTHPAP)
5339 {
5340 strcpy(config->radius_authtypes_s, "pap");
5341 if (config->radius_authtypes & AUTHCHAP)
5342 strcat(config->radius_authtypes_s, ", chap");
5343 }
5344 else
5345 {
5346 strcpy(config->radius_authtypes_s, "chap");
5347 if (config->radius_authtypes & AUTHPAP)
5348 strcat(config->radius_authtypes_s, ", pap");
5349 }
5350
5351 if (!config->radius_dae_port)
5352 config->radius_dae_port = DAEPORT;
5353
5354 if(!config->bind_portremotelns)
5355 config->bind_portremotelns = L2TPLACPORT;
5356 if(!config->bind_address_remotelns)
5357 config->bind_address_remotelns = INADDR_ANY;
5358
5359 if (*config->bind_multi_address)
5360 {
5361 char *sip = config->bind_multi_address;
5362 char *n = sip;
5363 char *e = config->bind_multi_address + strlen(config->bind_multi_address);
5364 config->nbmultiaddress = 0;
5365
5366 while (*sip && (sip < e))
5367 {
5368 in_addr_t ip = 0;
5369 uint8_t u = 0;
5370
5371 while (n < e && (*n == ',' || *n == ' ')) n++;
5372
5373 while (n < e && (isdigit(*n) || *n == '.'))
5374 {
5375 if (*n == '.')
5376 {
5377 ip = (ip << 8) + u;
5378 u = 0;
5379 }
5380 else
5381 u = u * 10 + *n - '0';
5382 n++;
5383 }
5384 ip = (ip << 8) + u;
5385 n++;
5386
5387 if (ip)
5388 {
5389 config->bind_n_address[config->nbmultiaddress] = htonl(ip);
5390 config->iftun_n_address[config->nbmultiaddress] = htonl(ip);
5391 config->nbmultiaddress++;
5392 LOG(1, 0, 0, "Bind address %s\n", fmtaddr(htonl(ip), 0));
5393 }
5394
5395 sip = n;
5396 }
5397
5398 if (config->nbmultiaddress >= 1)
5399 {
5400 config->bind_address = config->bind_n_address[0];
5401 config->iftun_address = config->bind_address;
5402 }
5403 }
5404
5405 if(!config->iftun_address)
5406 {
5407 config->iftun_address = config->bind_address;
5408 config->iftun_n_address[0] = config->iftun_address;
5409 }
5410
5411 if (!*config->pppoe_ac_name)
5412 strncpy(config->pppoe_ac_name, DEFAULT_PPPOE_AC_NAME, sizeof(config->pppoe_ac_name) - 1);
5413
5414 // re-initialise the random number source
5415 initrandom(config->random_device);
5416
5417 // Update plugins
5418 for (i = 0; i < MAXPLUGINS; i++)
5419 {
5420 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
5421 continue;
5422
5423 if (*config->plugins[i])
5424 {
5425 // Plugin added
5426 add_plugin(config->plugins[i]);
5427 }
5428 else if (*config->old_plugins[i])
5429 {
5430 // Plugin removed
5431 remove_plugin(config->old_plugins[i]);
5432 }
5433 }
5434
5435 // Guest change
5436 guest_accounts_num = 0;
5437 char *p2 = config->guest_user;
5438 while (p2 && *p2)
5439 {
5440 char *s = strpbrk(p2, " \t,");
5441 if (s)
5442 {
5443 *s++ = 0;
5444 while (*s == ' ' || *s == '\t')
5445 s++;
5446
5447 if (!*s)
5448 s = 0;
5449 }
5450
5451 strcpy(guest_users[guest_accounts_num], p2);
5452 LOG(1, 0, 0, "Guest account[%d]: %s\n", guest_accounts_num, guest_users[guest_accounts_num]);
5453 guest_accounts_num++;
5454 p2 = s;
5455 }
5456 // Rebuild the guest_user array
5457 strcpy(config->guest_user, "");
5458 int ui = 0;
5459 for (ui=0; ui<guest_accounts_num; ui++)
5460 {
5461 strcat(config->guest_user, guest_users[ui]);
5462 if (ui<guest_accounts_num-1)
5463 {
5464 strcat(config->guest_user, ",");
5465 }
5466 }
5467
5468
5469 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
5470 if (!config->multi_read_count) config->multi_read_count = 10;
5471 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
5472 if (!*config->cluster_interface)
5473 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
5474
5475 if (!config->cluster_hb_interval)
5476 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
5477
5478 if (!config->cluster_hb_timeout)
5479 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
5480
5481 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
5482 {
5483 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
5484 // late, ensure we're sufficiently larger than that
5485 int t = 4 * config->cluster_hb_interval + 11;
5486
5487 if (config->cluster_hb_timeout < t)
5488 {
5489 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
5490 config->cluster_hb_timeout = t;
5491 }
5492
5493 // Push timing changes to the slaves immediately if we're the master
5494 if (config->cluster_iam_master)
5495 cluster_heartbeat();
5496
5497 interval = config->cluster_hb_interval;
5498 timeout = config->cluster_hb_timeout;
5499 }
5500
5501 // Write PID file
5502 if (*config->pid_file == '/' && !config->wrote_pid)
5503 {
5504 FILE *f;
5505 if ((f = fopen(config->pid_file, "w")))
5506 {
5507 fprintf(f, "%d\n", getpid());
5508 fclose(f);
5509 config->wrote_pid = 1;
5510 }
5511 else
5512 {
5513 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
5514 }
5515 }
5516 }
5517
5518 static void read_config_file()
5519 {
5520 FILE *f;
5521
5522 if (!config->config_file) return;
5523 if (!(f = fopen(config->config_file, "r")))
5524 {
5525 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
5526 return;
5527 }
5528
5529 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
5530 cli_do_file(f);
5531 LOG(3, 0, 0, "Done reading config file\n");
5532 fclose(f);
5533 }
5534
5535 int sessionsetup(sessionidt s, tunnelidt t)
5536 {
5537 // A session now exists, set it up
5538 in_addr_t ip;
5539 char *user;
5540 sessionidt i;
5541 int r;
5542
5543 CSTAT(sessionsetup);
5544
5545 LOG(3, s, t, "Doing session setup for session\n");
5546
5547 // Join a bundle if the MRRU option is accepted
5548 if(session[s].mrru > 0 && session[s].bundle == 0)
5549 {
5550 LOG(3, s, t, "This session can be part of multilink bundle\n");
5551 if (join_bundle(s) > 0)
5552 cluster_send_bundle(session[s].bundle);
5553 else
5554 {
5555 LOG(0, s, t, "MPPP: Mismaching mssf option with other sessions in bundle\n");
5556 sessionshutdown(s, "Mismaching mssf option.", CDN_NONE, TERM_SERVICE_UNAVAILABLE);
5557 return 0;
5558 }
5559 }
5560
5561 if (!session[s].ip)
5562 {
5563 assign_ip_address(s);
5564 if (!session[s].ip)
5565 {
5566 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
5567 sessionshutdown(s, "No IP addresses available.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
5568 return 0;
5569 }
5570 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
5571 fmtaddr(htonl(session[s].ip), 0));
5572 }
5573
5574 // Make sure this is right
5575 session[s].tunnel = t;
5576
5577 // zap old sessions with same IP and/or username
5578 // Don't kill gardened sessions - doing so leads to a DoS
5579 // from someone who doesn't need to know the password
5580 {
5581 ip = session[s].ip;
5582 user = session[s].user;
5583 for (i = 1; i <= config->cluster_highest_sessionid; i++)
5584 {
5585 if (i == s) continue;
5586 if (!session[s].opened) break;
5587 // Allow duplicate sessions for multilink ones of the same bundle.
5588 if (session[s].bundle && session[i].bundle && session[s].bundle == session[i].bundle) continue;
5589
5590 if (ip == session[i].ip)
5591 {
5592 sessionshutdown(i, "Duplicate IP address", CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
5593 continue;
5594 }
5595
5596 if (config->allow_duplicate_users) continue;
5597 if (session[s].walled_garden || session[i].walled_garden) continue;
5598 // Guest change
5599 int found = 0;
5600 int gu;
5601 for (gu = 0; gu < guest_accounts_num; gu++)
5602 {
5603 if (!strcasecmp(user, guest_users[gu]))
5604 {
5605 found = 1;
5606 break;
5607 }
5608 }
5609 if (found) continue;
5610
5611 // Drop the new session in case of duplicate sessionss, not the old one.
5612 if (!strcasecmp(user, session[i].user))
5613 sessionshutdown(i, "Duplicate session for users", CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
5614 }
5615 }
5616
5617 // no need to set a route for the same IP address of the bundle
5618 if (!session[s].bundle || (bundle[session[s].bundle].num_of_links == 1))
5619 {
5620 int routed = 0;
5621
5622 // Add the route for this session.
5623 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
5624 {
5625 if ((session[s].ip >> (32-session[s].route[r].prefixlen)) ==
5626 (session[s].route[r].ip >> (32-session[s].route[r].prefixlen)))
5627 routed++;
5628
5629 routeset(s, session[s].route[r].ip, session[s].route[r].prefixlen, 0, 1);
5630 }
5631
5632 // Static IPs need to be routed if not already
5633 // convered by a Framed-Route. Anything else is part
5634 // of the IP address pool and is already routed, it
5635 // just needs to be added to the IP cache.
5636 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
5637 if (session[s].ip_pool_index == -1) // static ip
5638 {
5639 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
5640 }
5641 else
5642 cache_ipmap(session[s].ip, s);
5643 }
5644
5645 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
5646 lcp_open(s, t); // transition to Network phase and send initial IPCP
5647
5648 // Run the plugin's against this new session.
5649 {
5650 struct param_new_session data = { &tunnel[t], &session[s] };
5651 run_plugins(PLUGIN_NEW_SESSION, &data);
5652 }
5653
5654 // Allocate TBFs if throttled
5655 if (session[s].throttle_in || session[s].throttle_out)
5656 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
5657
5658 session[s].last_packet = session[s].last_data = time_now;
5659
5660 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
5661 fmtaddr(htonl(session[s].ip), 0),
5662 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
5663
5664 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
5665
5666 return 1; // RADIUS OK and IP allocated, done...
5667 }
5668
5669 //
5670 // This session just got dropped on us by the master or something.
5671 // Make sure our tables up up to date...
5672 //
5673 int load_session(sessionidt s, sessiont *new)
5674 {
5675 int i;
5676 int newip = 0;
5677
5678 // Sanity checks.
5679 if (new->ip_pool_index >= MAXIPPOOL ||
5680 new->tunnel >= MAXTUNNEL)
5681 {
5682 LOG(0, s, 0, "Strange session update received!\n");
5683 // FIXME! What to do here?
5684 return 0;
5685 }
5686
5687 //
5688 // Ok. All sanity checks passed. Now we're committed to
5689 // loading the new session.
5690 //
5691
5692 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
5693
5694 // See if routes/ip cache need updating
5695 if (new->ip != session[s].ip)
5696 newip++;
5697
5698 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
5699 if (new->route[i].ip != session[s].route[i].ip ||
5700 new->route[i].prefixlen != session[s].route[i].prefixlen)
5701 newip++;
5702
5703 // needs update
5704 if (newip)
5705 {
5706 int routed = 0;
5707
5708 // remove old routes...
5709 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
5710 {
5711 if ((session[s].ip >> (32-session[s].route[i].prefixlen)) ==
5712 (session[s].route[i].ip >> (32-session[s].route[i].prefixlen)))
5713 routed++;
5714
5715 routeset(s, session[s].route[i].ip, session[s].route[i].prefixlen, 0, 0);
5716 }
5717
5718 // ...ip
5719 if (session[s].ip)
5720 {
5721 if (session[s].ip_pool_index == -1) // static IP
5722 {
5723 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
5724 }
5725 else // It's part of the IP pool, remove it manually.
5726 uncache_ipmap(session[s].ip);
5727 }
5728
5729 routed = 0;
5730
5731 // add new routes...
5732 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
5733 {
5734 if ((new->ip >> (32-new->route[i].prefixlen)) ==
5735 (new->route[i].ip >> (32-new->route[i].prefixlen)))
5736 routed++;
5737
5738 routeset(s, new->route[i].ip, new->route[i].prefixlen, 0, 1);
5739 }
5740
5741 // ...ip
5742 if (new->ip)
5743 {
5744 // If there's a new one, add it.
5745 if (new->ip_pool_index == -1)
5746 {
5747 if (!routed) routeset(s, new->ip, 0, 0, 1);
5748 }
5749 else
5750 cache_ipmap(new->ip, s);
5751 }
5752 }
5753
5754 // check v6 routing
5755 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
5756 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
5757
5758 // check filters
5759 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
5760 {
5761 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %u\n", (int) new->filter_in);
5762 new->filter_in = 0;
5763 }
5764
5765 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
5766 {
5767 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %u\n", (int) new->filter_out);
5768 new->filter_out = 0;
5769 }
5770
5771 if (new->filter_in != session[s].filter_in)
5772 {
5773 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
5774 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
5775 }
5776
5777 if (new->filter_out != session[s].filter_out)
5778 {
5779 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
5780 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
5781 }
5782
5783 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
5784 // for walking the sessions to forward byte counts to the master.
5785 config->cluster_highest_sessionid = s;
5786
5787 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
5788
5789 // Do fixups into address pool.
5790 if (new->ip_pool_index != -1)
5791 fix_address_pool(s);
5792
5793 return 1;
5794 }
5795
5796 static void initplugins()
5797 {
5798 int i;
5799
5800 loaded_plugins = ll_init();
5801 // Initialize the plugins to nothing
5802 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
5803 plugins[i] = ll_init();
5804 }
5805
5806 static void *open_plugin(char *plugin_name, int load)
5807 {
5808 char path[256] = "";
5809
5810 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
5811 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
5812 return dlopen(path, RTLD_NOW);
5813 }
5814
5815 // plugin callback to get a config value
5816 static void *getconfig(char *key, enum config_typet type)
5817 {
5818 int i;
5819
5820 for (i = 0; config_values[i].key; i++)
5821 {
5822 if (!strcmp(config_values[i].key, key))
5823 {
5824 if (config_values[i].type == type)
5825 return ((void *) config) + config_values[i].offset;
5826
5827 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
5828 key, type, config_values[i].type);
5829
5830 return 0;
5831 }
5832 }
5833
5834 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
5835 return 0;
5836 }
5837
5838 static int add_plugin(char *plugin_name)
5839 {
5840 static struct pluginfuncs funcs = {
5841 _log,
5842 _log_hex,
5843 fmtaddr,
5844 sessionbyuser,
5845 sessiontbysessionidt,
5846 sessionidtbysessiont,
5847 radiusnew,
5848 radiussend,
5849 getconfig,
5850 sessionshutdown,
5851 sessionkill,
5852 throttle_session,
5853 cluster_send_session,
5854 };
5855
5856 void *p = open_plugin(plugin_name, 1);
5857 int (*initfunc)(struct pluginfuncs *);
5858 int i;
5859
5860 if (!p)
5861 {
5862 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
5863 return -1;
5864 }
5865
5866 if (ll_contains(loaded_plugins, p))
5867 {
5868 dlclose(p);
5869 return 0; // already loaded
5870 }
5871
5872 {
5873 int *v = dlsym(p, "plugin_api_version");
5874 if (!v || *v != PLUGIN_API_VERSION)
5875 {
5876 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
5877 dlclose(p);
5878 return -1;
5879 }
5880 }
5881
5882 if ((initfunc = dlsym(p, "plugin_init")))
5883 {
5884 if (!initfunc(&funcs))
5885 {
5886 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
5887 dlclose(p);
5888 return -1;
5889 }
5890 }
5891
5892 ll_push(loaded_plugins, p);
5893
5894 for (i = 0; i < max_plugin_functions; i++)
5895 {
5896 void *x;
5897 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5898 {
5899 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
5900 ll_push(plugins[i], x);
5901 }
5902 }
5903
5904 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
5905 return 1;
5906 }
5907
5908 static void run_plugin_done(void *plugin)
5909 {
5910 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
5911
5912 if (donefunc)
5913 donefunc();
5914 }
5915
5916 static int remove_plugin(char *plugin_name)
5917 {
5918 void *p = open_plugin(plugin_name, 0);
5919 int loaded = 0;
5920
5921 if (!p)
5922 return -1;
5923
5924 if (ll_contains(loaded_plugins, p))
5925 {
5926 int i;
5927 for (i = 0; i < max_plugin_functions; i++)
5928 {
5929 void *x;
5930 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5931 ll_delete(plugins[i], x);
5932 }
5933
5934 ll_delete(loaded_plugins, p);
5935 run_plugin_done(p);
5936 loaded = 1;
5937 }
5938
5939 dlclose(p);
5940 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
5941 return loaded;
5942 }
5943
5944 int run_plugins(int plugin_type, void *data)
5945 {
5946 int (*func)(void *data);
5947
5948 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
5949 return PLUGIN_RET_ERROR;
5950
5951 ll_reset(plugins[plugin_type]);
5952 while ((func = ll_next(plugins[plugin_type])))
5953 {
5954 int r = func(data);
5955
5956 if (r != PLUGIN_RET_OK)
5957 return r; // stop here
5958 }
5959
5960 return PLUGIN_RET_OK;
5961 }
5962
5963 static void plugins_done()
5964 {
5965 void *p;
5966
5967 ll_reset(loaded_plugins);
5968 while ((p = ll_next(loaded_plugins)))
5969 run_plugin_done(p);
5970 }
5971
5972 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
5973 {
5974 struct nsctl request;
5975 struct nsctl response;
5976 int type = unpack_control(&request, buf, len);
5977 int r;
5978 void *p;
5979
5980 if (log_stream && config->debug >= 4)
5981 {
5982 if (type < 0)
5983 {
5984 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
5985 fmtaddr(addr->sin_addr.s_addr, 0), type);
5986 }
5987 else
5988 {
5989 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5990 dump_control(&request, log_stream);
5991 }
5992 }
5993
5994 switch (type)
5995 {
5996 case NSCTL_REQ_LOAD:
5997 if (request.argc != 1)
5998 {
5999 response.type = NSCTL_RES_ERR;
6000 response.argc = 1;
6001 response.argv[0] = "name of plugin required";
6002 }
6003 else if ((r = add_plugin(request.argv[0])) < 1)
6004 {
6005 response.type = NSCTL_RES_ERR;
6006 response.argc = 1;
6007 response.argv[0] = !r
6008 ? "plugin already loaded"
6009 : "error loading plugin";
6010 }
6011 else
6012 {
6013 response.type = NSCTL_RES_OK;
6014 response.argc = 0;
6015 }
6016
6017 break;
6018
6019 case NSCTL_REQ_UNLOAD:
6020 if (request.argc != 1)
6021 {
6022 response.type = NSCTL_RES_ERR;
6023 response.argc = 1;
6024 response.argv[0] = "name of plugin required";
6025 }
6026 else if ((r = remove_plugin(request.argv[0])) < 1)
6027 {
6028 response.type = NSCTL_RES_ERR;
6029 response.argc = 1;
6030 response.argv[0] = !r
6031 ? "plugin not loaded"
6032 : "plugin not found";
6033 }
6034 else
6035 {
6036 response.type = NSCTL_RES_OK;
6037 response.argc = 0;
6038 }
6039
6040 break;
6041
6042 case NSCTL_REQ_HELP:
6043 response.type = NSCTL_RES_OK;
6044 response.argc = 0;
6045
6046 ll_reset(loaded_plugins);
6047 while ((p = ll_next(loaded_plugins)))
6048 {
6049 char **help = dlsym(p, "plugin_control_help");
6050 while (response.argc < 0xff && help && *help)
6051 response.argv[response.argc++] = *help++;
6052 }
6053
6054 break;
6055
6056 case NSCTL_REQ_CONTROL:
6057 {
6058 struct param_control param = {
6059 config->cluster_iam_master,
6060 request.argc,
6061 request.argv,
6062 0,
6063 NULL,
6064 };
6065
6066 int r = run_plugins(PLUGIN_CONTROL, &param);
6067
6068 if (r == PLUGIN_RET_ERROR)
6069 {
6070 response.type = NSCTL_RES_ERR;
6071 response.argc = 1;
6072 response.argv[0] = param.additional
6073 ? param.additional
6074 : "error returned by plugin";
6075 }
6076 else if (r == PLUGIN_RET_NOTMASTER)
6077 {
6078 static char msg[] = "must be run on master: 000.000.000.000";
6079
6080 response.type = NSCTL_RES_ERR;
6081 response.argc = 1;
6082 if (config->cluster_master_address)
6083 {
6084 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
6085 response.argv[0] = msg;
6086 }
6087 else
6088 {
6089 response.argv[0] = "must be run on master: none elected";
6090 }
6091 }
6092 else if (!(param.response & NSCTL_RESPONSE))
6093 {
6094 response.type = NSCTL_RES_ERR;
6095 response.argc = 1;
6096 response.argv[0] = param.response
6097 ? "unrecognised response value from plugin"
6098 : "unhandled action";
6099 }
6100 else
6101 {
6102 response.type = param.response;
6103 response.argc = 0;
6104 if (param.additional)
6105 {
6106 response.argc = 1;
6107 response.argv[0] = param.additional;
6108 }
6109 }
6110 }
6111
6112 break;
6113
6114 default:
6115 response.type = NSCTL_RES_ERR;
6116 response.argc = 1;
6117 response.argv[0] = "error unpacking control packet";
6118 }
6119
6120 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
6121 if (!buf)
6122 {
6123 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
6124 return;
6125 }
6126
6127 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
6128 if (r > 0)
6129 {
6130 sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
6131 if (log_stream && config->debug >= 4)
6132 {
6133 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
6134 dump_control(&response, log_stream);
6135 }
6136 }
6137 else
6138 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
6139 fmtaddr(addr->sin_addr.s_addr, 0), r);
6140
6141 free(buf);
6142 }
6143
6144 static tunnelidt new_tunnel()
6145 {
6146 tunnelidt i;
6147 for (i = 1; i < MAXTUNNEL; i++)
6148 {
6149 if ((tunnel[i].state == TUNNELFREE) && (i != TUNNEL_ID_PPPOE))
6150 {
6151 LOG(4, 0, i, "Assigning tunnel ID %u\n", i);
6152 if (i > config->cluster_highest_tunnelid)
6153 config->cluster_highest_tunnelid = i;
6154 return i;
6155 }
6156 }
6157 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
6158 return 0;
6159 }
6160
6161 //
6162 // We're becoming the master. Do any required setup..
6163 //
6164 // This is principally telling all the plugins that we're
6165 // now a master, and telling them about all the sessions
6166 // that are active too..
6167 //
6168 void become_master(void)
6169 {
6170 int s, i;
6171 static struct event_data d[RADIUS_FDS];
6172 struct epoll_event e;
6173
6174 run_plugins(PLUGIN_BECOME_MASTER, NULL);
6175
6176 // running a bunch of iptables commands is slow and can cause
6177 // the master to drop tunnels on takeover--kludge around the
6178 // problem by forking for the moment (note: race)
6179 if (!fork_and_close())
6180 {
6181 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
6182 {
6183 if (!session[s].opened) // Not an in-use session.
6184 continue;
6185
6186 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
6187 }
6188 exit(0);
6189 }
6190
6191 // add radius fds
6192 e.events = EPOLLIN;
6193 for (i = 0; i < RADIUS_FDS; i++)
6194 {
6195 d[i].type = FD_TYPE_RADIUS;
6196 d[i].index = i;
6197 e.data.ptr = &d[i];
6198
6199 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
6200 }
6201 }
6202
6203 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
6204 {
6205 int s, i;
6206 int count = 0;
6207 int buckets[64];
6208
6209 if (CLI_HELP_REQUESTED)
6210 return CLI_HELP_NO_ARGS;
6211
6212 time(&time_now);
6213 for (i = 0; i < 64;++i) buckets[i] = 0;
6214
6215 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
6216 {
6217 int idle;
6218 if (!session[s].opened)
6219 continue;
6220
6221 idle = time_now - session[s].last_data;
6222 idle /= 5 ; // In multiples of 5 seconds.
6223 if (idle < 0)
6224 idle = 0;
6225 if (idle > 63)
6226 idle = 63;
6227
6228 ++count;
6229 ++buckets[idle];
6230 }
6231
6232 for (i = 0; i < 63; ++i)
6233 {
6234 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
6235 }
6236 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
6237 cli_print(cli, "%d total sessions open.", count);
6238 return CLI_OK;
6239 }
6240
6241 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
6242 {
6243 int s, i;
6244 int count = 0;
6245 int buckets[64];
6246
6247 if (CLI_HELP_REQUESTED)
6248 return CLI_HELP_NO_ARGS;
6249
6250 time(&time_now);
6251 for (i = 0; i < 64;++i) buckets[i] = 0;
6252
6253 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
6254 {
6255 int open = 0, d;
6256 if (!session[s].opened)
6257 continue;
6258
6259 d = time_now - session[s].opened;
6260 if (d < 0)
6261 d = 0;
6262 while (d > 1 && open < 32)
6263 {
6264 ++open;
6265 d >>= 1; // half.
6266 }
6267 ++count;
6268 ++buckets[open];
6269 }
6270
6271 s = 1;
6272 for (i = 0; i < 30; ++i)
6273 {
6274 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
6275 s <<= 1;
6276 }
6277 cli_print(cli, "%d total sessions open.", count);
6278 return CLI_OK;
6279 }
6280
6281 /* Unhide an avp.
6282 *
6283 * This unencodes the AVP using the L2TP secret and the previously
6284 * stored random vector. It overwrites the hidden data with the
6285 * unhidden AVP subformat.
6286 */
6287 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
6288 {
6289 MD5_CTX ctx;
6290 uint8_t digest[16];
6291 uint8_t *last;
6292 size_t d = 0;
6293 uint16_t m = htons(type);
6294
6295 // Compute initial pad
6296 MD5_Init(&ctx);
6297 MD5_Update(&ctx, (unsigned char *) &m, 2);
6298 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
6299 MD5_Update(&ctx, vector, vec_len);
6300 MD5_Final(digest, &ctx);
6301
6302 // pointer to last decoded 16 octets
6303 last = value;
6304
6305 while (len > 0)
6306 {
6307 // calculate a new pad based on the last decoded block
6308 if (d >= sizeof(digest))
6309 {
6310 MD5_Init(&ctx);
6311 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
6312 MD5_Update(&ctx, last, sizeof(digest));
6313 MD5_Final(digest, &ctx);
6314
6315 d = 0;
6316 last = value;
6317 }
6318
6319 *value++ ^= digest[d++];
6320 len--;
6321 }
6322 }
6323
6324 int find_filter(char const *name, size_t len)
6325 {
6326 int free = -1;
6327 int i;
6328
6329 for (i = 0; i < MAXFILTER; i++)
6330 {
6331 if (!*ip_filters[i].name)
6332 {
6333 if (free < 0)
6334 free = i;
6335
6336 continue;
6337 }
6338
6339 if (strlen(ip_filters[i].name) != len)
6340 continue;
6341
6342 if (!strncmp(ip_filters[i].name, name, len))
6343 return i;
6344 }
6345
6346 return free;
6347 }
6348
6349 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
6350 {
6351 switch (p->op)
6352 {
6353 case FILTER_PORT_OP_EQ: return port == p->port;
6354 case FILTER_PORT_OP_NEQ: return port != p->port;
6355 case FILTER_PORT_OP_GT: return port > p->port;
6356 case FILTER_PORT_OP_LT: return port < p->port;
6357 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
6358 }
6359
6360 return 0;
6361 }
6362
6363 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
6364 {
6365 switch (op)
6366 {
6367 case FILTER_FLAG_OP_ANY:
6368 return (flags & sflags) || (~flags & cflags);
6369
6370 case FILTER_FLAG_OP_ALL:
6371 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
6372
6373 case FILTER_FLAG_OP_EST:
6374 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
6375 }
6376
6377 return 0;
6378 }
6379
6380 int ip_filter(uint8_t *buf, int len, uint8_t filter)
6381 {
6382 uint16_t frag_offset;
6383 uint8_t proto;
6384 in_addr_t src_ip;
6385 in_addr_t dst_ip;
6386 uint16_t src_port = 0;
6387 uint16_t dst_port = 0;
6388 uint8_t flags = 0;
6389 ip_filter_rulet *rule;
6390
6391 if (len < 20) // up to end of destination address
6392 return 0;
6393
6394 if ((*buf >> 4) != 4) // IPv4
6395 return 0;
6396
6397 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
6398 proto = buf[9];
6399 src_ip = *(in_addr_t *) (buf + 12);
6400 dst_ip = *(in_addr_t *) (buf + 16);
6401
6402 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
6403 {
6404 int l = (buf[0] & 0xf) * 4; // length of IP header
6405 if (len < l + 4) // ports
6406 return 0;
6407
6408 src_port = ntohs(*(uint16_t *) (buf + l));
6409 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
6410 if (proto == IPPROTO_TCP)
6411 {
6412 if (len < l + 14) // flags
6413 return 0;
6414
6415 flags = buf[l + 13] & 0x3f;
6416 }
6417 }
6418
6419 for (rule = ip_filters[filter].rules; rule->action; rule++)
6420 {
6421 if (rule->proto != IPPROTO_IP && proto != rule->proto)
6422 continue;
6423
6424 if (rule->src_wild != INADDR_BROADCAST &&
6425 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
6426 continue;
6427
6428 if (rule->dst_wild != INADDR_BROADCAST &&
6429 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
6430 continue;
6431
6432 if (frag_offset)
6433 {
6434 // layer 4 deny rules are skipped
6435 if (rule->action == FILTER_ACTION_DENY &&
6436 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
6437 continue;
6438 }
6439 else
6440 {
6441 if (rule->frag)
6442 continue;
6443
6444 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
6445 {
6446 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
6447 continue;
6448
6449 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
6450 continue;
6451
6452 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
6453 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
6454 continue;
6455 }
6456 }
6457
6458 // matched
6459 rule->counter++;
6460 return rule->action == FILTER_ACTION_PERMIT;
6461 }
6462
6463 // default deny
6464 return 0;
6465 }
6466
6467 tunnelidt lac_new_tunnel()
6468 {
6469 return new_tunnel();
6470 }
6471
6472 void lac_tunnelclear(tunnelidt t)
6473 {
6474 tunnelclear(t);
6475 }
6476
6477 void lac_send_SCCRQ(tunnelidt t, uint8_t * auth, unsigned int auth_len)
6478 {
6479 uint16_t version = 0x0100; // protocol version
6480
6481 tunnel[t].state = TUNNELOPENING;
6482
6483 // Sent SCCRQ - Start Control Connection Request
6484 controlt *c = controlnew(1); // sending SCCRQ
6485 controls(c, 7, hostname, 1); // host name
6486 controls(c, 8, Vendor_name, 1); // Vendor name
6487 control16(c, 2, version, 1); // protocol version
6488 control32(c, 3, 3, 1); // framing Capabilities
6489 control16(c, 9, t, 1); // assigned tunnel
6490 controlb(c, 11, (uint8_t *) auth, auth_len, 1); // CHAP Challenge
6491 LOG(3, 0, t, "Sent SCCRQ to REMOTE LNS\n");
6492 controladd(c, 0, t); // send
6493 }
6494
6495 void lac_send_ICRQ(tunnelidt t, sessionidt s)
6496 {
6497 // Sent ICRQ Incoming-call-request
6498 controlt *c = controlnew(10); // ICRQ
6499
6500 control16(c, 14, s, 1); // assigned sesion
6501 call_serial_number++;
6502 control32(c, 15, call_serial_number, 1); // call serial number
6503 LOG(3, s, t, "Sent ICRQ to REMOTE LNS (far ID %u)\n", tunnel[t].far);
6504 controladd(c, 0, t); // send
6505 }
6506
6507 void lac_tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
6508 {
6509 tunnelshutdown(t, reason, result, error, msg);
6510 }
6511