af19f9af6bb552011745d2581adf6d12d2f817a2
[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 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.176 2011/01/20 12:48:40 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42 #include <linux/netlink.h>
43
44 #include "md5.h"
45 #include "l2tpns.h"
46 #include "cluster.h"
47 #include "plugin.h"
48 #include "ll.h"
49 #include "constants.h"
50 #include "control.h"
51 #include "util.h"
52 #include "tbf.h"
53
54 #ifdef BGP
55 #include "bgp.h"
56 #endif
57
58 // Globals
59 configt *config = NULL; // all configuration
60 int nlfd = -1; // netlink socket
61 int tunfd = -1; // tun interface file handle. (network device)
62 int udpfd = -1; // UDP file handle
63 int controlfd = -1; // Control signal handle
64 int clifd = -1; // Socket listening for CLI connections.
65 int daefd = -1; // Socket listening for DAE connections.
66 int snoopfd = -1; // UDP file handle for sending out intercept data
67 int *radfds = NULL; // RADIUS requests file handles
68 int ifrfd = -1; // File descriptor for routing, etc
69 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
70 int rand_fd = -1; // Random data source
71 int cluster_sockfd = -1; // Intra-cluster communications socket.
72 int epollfd = -1; // event polling
73 time_t basetime = 0; // base clock
74 char hostname[1000] = ""; // us.
75 static int tunidx; // ifr_ifindex of tun device
76 int nlseqnum = 0; // netlink sequence number
77 static int syslog_log = 0; // are we logging to syslog
78 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
79 uint32_t last_id = 0; // Unique ID for radius accounting
80 // Guest change
81 char guest_users[10][32]; // Array of guest users
82 int guest_accounts_num = 0; // Number of guest users
83
84 // calculated from config->l2tp_mtu
85 uint16_t MRU = 0; // PPP MRU
86 uint16_t MSS = 0; // TCP MSS
87
88 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
89 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
90
91 union iphash {
92 sessionidt sess;
93 union iphash *idx;
94 } ip_hash[256]; // Mapping from IP address to session structures.
95
96 struct ipv6radix {
97 sessionidt sess;
98 struct ipv6radix *branch;
99 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
100
101 // Traffic counters.
102 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
103 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
104 uint32_t eth_tx = 0;
105
106 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
107 time_t time_now = 0; // Current time in seconds since epoch.
108 static char time_now_string[64] = {0}; // Current time as a string.
109 static int time_changed = 0; // time_now changed
110 char main_quit = 0; // True if we're in the process of exiting.
111 static char main_reload = 0; // Re-load pending
112 linked_list *loaded_plugins;
113 linked_list *plugins[MAX_PLUGIN_TYPES];
114
115 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
116 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
117
118 config_descriptt config_values[] = {
119 CONFIG("debug", debug, INT),
120 CONFIG("log_file", log_filename, STRING),
121 CONFIG("pid_file", pid_file, STRING),
122 CONFIG("random_device", random_device, STRING),
123 CONFIG("l2tp_secret", l2tp_secret, STRING),
124 CONFIG("l2tp_mtu", l2tp_mtu, INT),
125 CONFIG("ppp_restart_time", ppp_restart_time, INT),
126 CONFIG("ppp_max_configure", ppp_max_configure, INT),
127 CONFIG("ppp_max_failure", ppp_max_failure, INT),
128 CONFIG("primary_dns", default_dns1, IPv4),
129 CONFIG("secondary_dns", default_dns2, IPv4),
130 CONFIG("primary_radius", radiusserver[0], IPv4),
131 CONFIG("secondary_radius", radiusserver[1], IPv4),
132 CONFIG("primary_radius_port", radiusport[0], SHORT),
133 CONFIG("secondary_radius_port", radiusport[1], SHORT),
134 CONFIG("radius_accounting", radius_accounting, BOOL),
135 CONFIG("radius_interim", radius_interim, INT),
136 CONFIG("radius_secret", radiussecret, STRING),
137 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
138 CONFIG("radius_dae_port", radius_dae_port, SHORT),
139 CONFIG("radius_bind_min", radius_bind_min, SHORT),
140 CONFIG("radius_bind_max", radius_bind_max, SHORT),
141 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
142 CONFIG("kill_timedout_sessions", kill_timedout_sessions, BOOL),
143 CONFIG("guest_account", guest_user, STRING),
144 CONFIG("bind_address", bind_address, IPv4),
145 CONFIG("peer_address", peer_address, IPv4),
146 CONFIG("send_garp", send_garp, BOOL),
147 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
148 CONFIG("throttle_buckets", num_tbfs, INT),
149 CONFIG("accounting_dir", accounting_dir, STRING),
150 CONFIG("dump_speed", dump_speed, BOOL),
151 CONFIG("multi_read_count", multi_read_count, INT),
152 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
153 CONFIG("lock_pages", lock_pages, BOOL),
154 CONFIG("icmp_rate", icmp_rate, INT),
155 CONFIG("packet_limit", max_packets, INT),
156 CONFIG("cluster_address", cluster_address, IPv4),
157 CONFIG("cluster_interface", cluster_interface, STRING),
158 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
159 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
160 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
161 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
162 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
163 { NULL, 0, 0, 0 },
164 };
165
166 static char *plugin_functions[] = {
167 NULL,
168 "plugin_pre_auth",
169 "plugin_post_auth",
170 "plugin_packet_rx",
171 "plugin_packet_tx",
172 "plugin_timer",
173 "plugin_new_session",
174 "plugin_kill_session",
175 "plugin_control",
176 "plugin_radius_response",
177 "plugin_radius_reset",
178 "plugin_radius_account",
179 "plugin_become_master",
180 "plugin_new_session_master",
181 };
182
183 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
184
185 // Counters for shutdown sessions
186 static sessiont shut_acct[8192];
187 static sessionidt shut_acct_n = 0;
188
189 tunnelt *tunnel = NULL; // Array of tunnel structures.
190 bundlet *bundle = NULL; // Array of bundle structures.
191 fragmentationt *frag = NULL; // Array of fragmentation structures.
192 sessiont *session = NULL; // Array of session structures.
193 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
194 radiust *radius = NULL; // Array of radius structures.
195 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
196 ip_filtert *ip_filters = NULL; // Array of named filters.
197 static controlt *controlfree = 0;
198 struct Tstats *_statistics = NULL;
199 #ifdef RINGBUFFER
200 struct Tringbuffer *ringbuffer = NULL;
201 #endif
202
203 static void cache_ipmap(in_addr_t ip, sessionidt s);
204 static void uncache_ipmap(in_addr_t ip);
205 static void cache_ipv6map(struct in6_addr ip, int prefixlen, sessionidt s);
206 static void free_ip_address(sessionidt s);
207 static void dump_acct_info(int all);
208 static void sighup_handler(int sig);
209 static void shutdown_handler(int sig);
210 static void sigchild_handler(int sig);
211 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
212 static void update_config(void);
213 static void read_config_file(void);
214 static void initplugins(void);
215 static int add_plugin(char *plugin_name);
216 static int remove_plugin(char *plugin_name);
217 static void plugins_done(void);
218 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
219 static tunnelidt new_tunnel(void);
220 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
221 static void bundleclear(bundleidt b);
222
223 // on slaves, alow BGP to withdraw cleanly before exiting
224 #define QUIT_DELAY 5
225
226 // quit actions (master)
227 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
228 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
229
230 // return internal time (10ths since process startup), set f if given
231 // as a side-effect sets time_now, and time_changed
232 static clockt now(double *f)
233 {
234 struct timeval t;
235 gettimeofday(&t, 0);
236 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
237 if (t.tv_sec != time_now)
238 {
239 time_now = t.tv_sec;
240 time_changed++;
241 }
242 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
243 }
244
245 // work out a retry time based on try number
246 // This is a straight bounded exponential backoff.
247 // Maximum re-try time is 32 seconds. (2^5).
248 clockt backoff(uint8_t try)
249 {
250 if (try > 5) try = 5; // max backoff
251 return now(NULL) + 10 * (1 << try);
252 }
253
254
255 //
256 // Log a debug message. Typically called via the LOG macro
257 //
258 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
259 {
260 static char message[65536] = {0};
261 va_list ap;
262
263 #ifdef RINGBUFFER
264 if (ringbuffer)
265 {
266 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
267 ringbuffer->tail = 0;
268 if (ringbuffer->tail == ringbuffer->head)
269 if (++ringbuffer->head >= RINGBUFFER_SIZE)
270 ringbuffer->head = 0;
271
272 ringbuffer->buffer[ringbuffer->tail].level = level;
273 ringbuffer->buffer[ringbuffer->tail].session = s;
274 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
275 va_start(ap, format);
276 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
277 va_end(ap);
278 }
279 #endif
280
281 if (config->debug < level) return;
282
283 va_start(ap, format);
284 vsnprintf(message, sizeof(message), format, ap);
285
286 if (log_stream)
287 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
288 else if (syslog_log)
289 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
290
291 va_end(ap);
292 }
293
294 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
295 {
296 int i, j;
297 const uint8_t *d = data;
298
299 if (config->debug < level) return;
300
301 // No support for _log_hex to syslog
302 if (log_stream)
303 {
304 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
305 setvbuf(log_stream, NULL, _IOFBF, 16384);
306
307 for (i = 0; i < maxsize; )
308 {
309 fprintf(log_stream, "%4X: ", i);
310 for (j = i; j < maxsize && j < (i + 16); j++)
311 {
312 fprintf(log_stream, "%02X ", d[j]);
313 if (j == i + 7)
314 fputs(": ", log_stream);
315 }
316
317 for (; j < i + 16; j++)
318 {
319 fputs(" ", log_stream);
320 if (j == i + 7)
321 fputs(": ", log_stream);
322 }
323
324 fputs(" ", log_stream);
325 for (j = i; j < maxsize && j < (i + 16); j++)
326 {
327 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
328 fputc(d[j], log_stream);
329 else
330 fputc('.', log_stream);
331
332 if (j == i + 7)
333 fputs(" ", log_stream);
334 }
335
336 i = j;
337 fputs("\n", log_stream);
338 }
339
340 fflush(log_stream);
341 setbuf(log_stream, NULL);
342 }
343 }
344
345 // update a counter, accumulating 2^32 wraps
346 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
347 {
348 uint32_t new = *counter + delta;
349 if (new < *counter)
350 (*wrap)++;
351
352 *counter = new;
353 }
354
355 // initialise the random generator
356 static void initrandom(char *source)
357 {
358 static char path[sizeof(config->random_device)] = "*undefined*";
359
360 // reinitialise only if we are forced to do so or if the config has changed
361 if (source && !strncmp(path, source, sizeof(path)))
362 return;
363
364 // close previous source, if any
365 if (rand_fd >= 0)
366 close(rand_fd);
367
368 rand_fd = -1;
369
370 if (source)
371 {
372 // register changes
373 snprintf(path, sizeof(path), "%s", source);
374
375 if (*path == '/')
376 {
377 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
378 if (rand_fd < 0)
379 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
380 path, strerror(errno));
381 }
382 }
383 }
384
385 // fill buffer with random data
386 void random_data(uint8_t *buf, int len)
387 {
388 int n = 0;
389
390 CSTAT(random_data);
391 if (rand_fd >= 0)
392 {
393 n = read(rand_fd, buf, len);
394 if (n >= len) return;
395 if (n < 0)
396 {
397 if (errno != EAGAIN)
398 {
399 LOG(0, 0, 0, "Error reading from random source: %s\n",
400 strerror(errno));
401
402 // fall back to rand()
403 initrandom(NULL);
404 }
405
406 n = 0;
407 }
408 }
409
410 // append missing data
411 while (n < len)
412 // not using the low order bits from the prng stream
413 buf[n++] = (rand() >> 4) & 0xff;
414 }
415
416 // Add a route
417 //
418 // This adds it to the routing table, advertises it
419 // via BGP if enabled, and stuffs it into the
420 // 'sessionbyip' cache.
421 //
422 // 'ip' and 'mask' must be in _host_ order.
423 //
424 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
425 {
426 struct rtentry r;
427 int i;
428
429 if (!mask) mask = 0xffffffff;
430
431 ip &= mask; // Force the ip to be the first one in the route.
432
433 memset(&r, 0, sizeof(r));
434 r.rt_dev = config->tundevice;
435 r.rt_dst.sa_family = AF_INET;
436 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
437 r.rt_gateway.sa_family = AF_INET;
438 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
439 r.rt_genmask.sa_family = AF_INET;
440 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
441 r.rt_flags = (RTF_UP | RTF_STATIC);
442 if (gw)
443 r.rt_flags |= RTF_GATEWAY;
444 else if (mask == 0xffffffff)
445 r.rt_flags |= RTF_HOST;
446
447 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
448 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
449 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
450
451 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
452 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
453
454 #ifdef BGP
455 if (add)
456 bgp_add_route(htonl(ip), htonl(mask));
457 else
458 bgp_del_route(htonl(ip), htonl(mask));
459 #endif /* BGP */
460
461 // Add/Remove the IPs to the 'sessionbyip' cache.
462 // Note that we add the zero address in the case of
463 // a network route. Roll on CIDR.
464
465 // Note that 's == 0' implies this is the address pool.
466 // We still cache it here, because it will pre-fill
467 // the malloc'ed tree.
468
469 if (s)
470 {
471 if (!add) // Are we deleting a route?
472 s = 0; // Caching the session as '0' is the same as uncaching.
473
474 for (i = ip; (i&mask) == (ip&mask) ; ++i)
475 cache_ipmap(i, s);
476 }
477 }
478
479 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
480 {
481 struct in6_rtmsg rt;
482 char ipv6addr[INET6_ADDRSTRLEN];
483
484 if (ifr6fd < 0)
485 {
486 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
487 return;
488 }
489
490 memset(&rt, 0, sizeof(rt));
491
492 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
493 rt.rtmsg_dst_len = prefixlen;
494 rt.rtmsg_metric = 1;
495 rt.rtmsg_flags = RTF_UP;
496 rt.rtmsg_ifindex = tunidx;
497
498 LOG(1, 0, 0, "Route %s %s/%d\n",
499 add ? "add" : "del",
500 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
501 prefixlen);
502
503 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
504 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
505 strerror(errno));
506
507 // FIXME: need to add BGP routing (RFC2858)
508
509 if (s)
510 {
511 if (!add) // Are we deleting a route?
512 s = 0; // Caching the session as '0' is the same as uncaching.
513
514 cache_ipv6map(ip, prefixlen, s);
515 }
516
517 return;
518 }
519
520 //
521 // Set up netlink socket
522 static void initnetlink(void)
523 {
524 struct sockaddr_nl nladdr;
525
526 nlfd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
527 if (nlfd < 0)
528 return; // don't use netlink
529
530 memset(&nladdr, 0, sizeof(nladdr));
531 nladdr.nl_family = AF_NETLINK;
532 nladdr.nl_pid = getpid();
533
534 if (bind(fd, (struct sockaddr *)&nladdr, sizeof(nladdr)) < 0)
535 {
536 close(fd);
537 fd = -1;
538 return; // don't use netlink
539 }
540 }
541
542 static ssize_t netlink_send(struct nlmsghdr *nh)
543 {
544 struct sockaddr_nl nladdr;
545 struct iovec iov;
546 struct msghdr msg;
547 ssize_t len;
548 char buf[4096];
549 struct nlmsghdr *ack_nh;
550
551 nh->nlmsg_pid = getpid();
552 nh->nlmsg_seq = ++nlseqnum;
553 nh->nlmsg_flags |= NLM_F_ACK;
554
555 iov = { (void *)nh, nh->msg_len };
556 // set kernel address
557 memset(nladdr, 0, sizeof(nladdr));
558 nladdr.nl_family = AF_NETLINK;
559 msg = { (void *)&nladdr, sizeof(nladdr), &iov, 1, NULL, 0, 0 };
560
561 if ((len = sendmsg(nlfd, &msg, 0)) < 0)
562 return len; // return error code
563
564 // expect ack
565 iov = { buf, sizeof(buf) };
566 msg = { (void *)&nladdr, sizeof(nladdr), &iov, 1, NULL, 0, 0 };
567 if ((len = recvmsg(nlfd, &msg, 0)) < 0)
568 return len; // return error code
569
570 for (ack_nh = (struct nlmsghdr *)buf; NLMSG_OK (ack_nh, len);
571 ack_nh = NLMSG_NEXT (ack_nh, len))
572 {
573 if (ack_nh->nlmsg_type == NLMSG_DONE)
574 return 1; // didn't get the ack
575
576 if (ack_nh->nlmsg_type == NLMSG_ERROR)
577 {
578 struct nlmsgerr *errmsg = NLMSG_DATA(ack_nh);
579 if (errmsg->error)
580 return errmsg->error; // got an error back
581 if (errmsg->msg.nlmsg_seq == nh->nlmsg_seq)
582 return 0; // ack received
583 else
584 return 2; // wrong seq number?!
585 }
586 // unknown message
587 LOG(3, 0, 0, "Got an unknown netlink message: type %d\n", ack_nh->nlmsg_type);
588 }
589
590 return 3; // no end message?!
591 }
592
593 // defined in linux/ipv6.h, but tricky to include from user-space
594 // TODO: move routing to use netlink rather than ioctl
595 struct in6_ifreq {
596 struct in6_addr ifr6_addr;
597 __u32 ifr6_prefixlen;
598 unsigned int ifr6_ifindex;
599 };
600
601 //
602 // Set up TUN interface
603 static void inittun(void)
604 {
605 struct ifreq ifr;
606 struct in6_ifreq ifr6;
607 struct sockaddr_in sin = {0};
608 memset(&ifr, 0, sizeof(ifr));
609 ifr.ifr_flags = IFF_TUN;
610
611 tunfd = open(TUNDEVICE, O_RDWR);
612 if (tunfd < 0)
613 { // fatal
614 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
615 exit(1);
616 }
617 {
618 int flags = fcntl(tunfd, F_GETFL, 0);
619 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
620 }
621 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
622 {
623 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
624 exit(1);
625 }
626 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
627 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
628 {
629 struct nlmsghdr nlh;
630
631 {
632 LOG(0, 0, 0, "Error setting up tun device: %s", strerror(errno));
633 exit(1);
634 }
635 }
636 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
637
638 sin.sin_family = AF_INET;
639 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
640 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
641
642 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
643 {
644 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
645 exit(1);
646 }
647 /* Bump up the qlen to deal with bursts from the network */
648 ifr.ifr_qlen = 1000;
649 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
650 {
651 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
652 exit(1);
653 }
654 /* set MTU to modem MRU */
655 ifr.ifr_mtu = MRU;
656 if (ioctl(ifrfd, SIOCSIFMTU, (void *) &ifr) < 0)
657 {
658 LOG(0, 0, 0, "Error setting tun MTU: %s\n", strerror(errno));
659 exit(1);
660 }
661 ifr.ifr_flags = IFF_UP;
662 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
663 {
664 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
665 exit(1);
666 }
667 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
668 {
669 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
670 exit(1);
671 }
672 tunidx = ifr.ifr_ifindex;
673
674 // Only setup IPv6 on the tun device if we have a configured prefix
675 if (config->ipv6_prefix.s6_addr[0]) {
676 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
677
678 // Link local address is FE80::1
679 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
680 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
681 ifr6.ifr6_addr.s6_addr[1] = 0x80;
682 ifr6.ifr6_addr.s6_addr[15] = 1;
683 ifr6.ifr6_prefixlen = 64;
684 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
685 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
686 {
687 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
688 " %s\n", strerror(errno));
689 }
690
691 // Global address is prefix::1
692 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
693 ifr6.ifr6_addr = config->ipv6_prefix;
694 ifr6.ifr6_addr.s6_addr[15] = 1;
695 ifr6.ifr6_prefixlen = 64;
696 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
697 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
698 {
699 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
700 strerror(errno));
701 }
702 }
703 }
704
705 // set up UDP ports
706 static void initudp(void)
707 {
708 int on = 1;
709 struct sockaddr_in addr;
710
711 // Tunnel
712 memset(&addr, 0, sizeof(addr));
713 addr.sin_family = AF_INET;
714 addr.sin_port = htons(L2TPPORT);
715 addr.sin_addr.s_addr = config->bind_address;
716 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
717 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
718 {
719 int flags = fcntl(udpfd, F_GETFL, 0);
720 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
721 }
722 if (bind(udpfd, (struct sockaddr *) &addr, sizeof(addr)) < 0)
723 {
724 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
725 exit(1);
726 }
727
728 // Control
729 memset(&addr, 0, sizeof(addr));
730 addr.sin_family = AF_INET;
731 addr.sin_port = htons(NSCTL_PORT);
732 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
733 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
734 setsockopt(controlfd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
735 if (bind(controlfd, (struct sockaddr *) &addr, sizeof(addr)) < 0)
736 {
737 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
738 exit(1);
739 }
740
741 // Dynamic Authorization Extensions to RADIUS
742 memset(&addr, 0, sizeof(addr));
743 addr.sin_family = AF_INET;
744 addr.sin_port = htons(config->radius_dae_port);
745 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
746 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
747 setsockopt(daefd, SOL_IP, IP_PKTINFO, &on, sizeof(on)); // recvfromto
748 if (bind(daefd, (struct sockaddr *) &addr, sizeof(addr)) < 0)
749 {
750 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
751 exit(1);
752 }
753
754 // Intercept
755 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
756 }
757
758 //
759 // Find session by IP, < 1 for not found
760 //
761 // Confusingly enough, this 'ip' must be
762 // in _network_ order. This being the common
763 // case when looking it up from IP packet headers.
764 //
765 // We actually use this cache for two things.
766 // #1. For used IP addresses, this maps to the
767 // session ID that it's used by.
768 // #2. For un-used IP addresses, this maps to the
769 // index into the pool table that contains that
770 // IP address.
771 //
772
773 static sessionidt lookup_ipmap(in_addr_t ip)
774 {
775 uint8_t *a = (uint8_t *) &ip;
776 union iphash *h = ip_hash;
777
778 if (!(h = h[*a++].idx)) return 0;
779 if (!(h = h[*a++].idx)) return 0;
780 if (!(h = h[*a++].idx)) return 0;
781
782 return h[*a].sess;
783 }
784
785 static sessionidt lookup_ipv6map(struct in6_addr ip)
786 {
787 struct ipv6radix *curnode;
788 int i;
789 int s;
790 char ipv6addr[INET6_ADDRSTRLEN];
791
792 curnode = &ipv6_hash[ip.s6_addr[0]];
793 i = 1;
794 s = curnode->sess;
795
796 while (s == 0 && i < 15 && curnode->branch != NULL)
797 {
798 curnode = &curnode->branch[ip.s6_addr[i]];
799 s = curnode->sess;
800 i++;
801 }
802
803 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
804 inet_ntop(AF_INET6, &ip, ipv6addr,
805 INET6_ADDRSTRLEN),
806 s);
807
808 return s;
809 }
810
811 sessionidt sessionbyip(in_addr_t ip)
812 {
813 sessionidt s = lookup_ipmap(ip);
814 CSTAT(sessionbyip);
815
816 if (s > 0 && s < MAXSESSION && session[s].opened)
817 return s;
818
819 return 0;
820 }
821
822 sessionidt sessionbyipv6(struct in6_addr ip)
823 {
824 sessionidt s;
825 CSTAT(sessionbyipv6);
826
827 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
828 (ip.s6_addr[0] == 0xFE &&
829 ip.s6_addr[1] == 0x80 &&
830 ip.s6_addr16[1] == 0 &&
831 ip.s6_addr16[2] == 0 &&
832 ip.s6_addr16[3] == 0)) {
833 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
834 } else {
835 s = lookup_ipv6map(ip);
836 }
837
838 if (s > 0 && s < MAXSESSION && session[s].opened)
839 return s;
840
841 return 0;
842 }
843
844 //
845 // Take an IP address in HOST byte order and
846 // add it to the sessionid by IP cache.
847 //
848 // (It's actually cached in network order)
849 //
850 static void cache_ipmap(in_addr_t ip, sessionidt s)
851 {
852 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
853 uint8_t *a = (uint8_t *) &nip;
854 union iphash *h = ip_hash;
855 int i;
856
857 for (i = 0; i < 3; i++)
858 {
859 if (!(h[a[i]].idx || (h[a[i]].idx = calloc(256, sizeof(union iphash)))))
860 return;
861
862 h = h[a[i]].idx;
863 }
864
865 h[a[3]].sess = s;
866
867 if (s > 0)
868 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
869
870 else if (s == 0)
871 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
872 // else a map to an ip pool index.
873 }
874
875 static void uncache_ipmap(in_addr_t ip)
876 {
877 cache_ipmap(ip, 0); // Assign it to the NULL session.
878 }
879
880 static void cache_ipv6map(struct in6_addr ip, int prefixlen, sessionidt s)
881 {
882 int i;
883 int bytes;
884 struct ipv6radix *curnode;
885 char ipv6addr[INET6_ADDRSTRLEN];
886
887 curnode = &ipv6_hash[ip.s6_addr[0]];
888
889 bytes = prefixlen >> 3;
890 i = 1;
891 while (i < bytes) {
892 if (curnode->branch == NULL)
893 {
894 if (!(curnode->branch = calloc(256,
895 sizeof (struct ipv6radix))))
896 return;
897 }
898 curnode = &curnode->branch[ip.s6_addr[i]];
899 i++;
900 }
901
902 curnode->sess = s;
903
904 if (s > 0)
905 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
906 inet_ntop(AF_INET6, &ip, ipv6addr,
907 INET6_ADDRSTRLEN),
908 prefixlen);
909 else if (s == 0)
910 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
911 inet_ntop(AF_INET6, &ip, ipv6addr,
912 INET6_ADDRSTRLEN),
913 prefixlen);
914 }
915
916 //
917 // CLI list to dump current ipcache.
918 //
919 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
920 {
921 union iphash *d = ip_hash, *e, *f, *g;
922 int i, j, k, l;
923 int count = 0;
924
925 if (CLI_HELP_REQUESTED)
926 return CLI_HELP_NO_ARGS;
927
928 cli_print(cli, "%7s %s", "Sess#", "IP Address");
929
930 for (i = 0; i < 256; ++i)
931 {
932 if (!d[i].idx)
933 continue;
934
935 e = d[i].idx;
936 for (j = 0; j < 256; ++j)
937 {
938 if (!e[j].idx)
939 continue;
940
941 f = e[j].idx;
942 for (k = 0; k < 256; ++k)
943 {
944 if (!f[k].idx)
945 continue;
946
947 g = f[k].idx;
948 for (l = 0; l < 256; ++l)
949 {
950 if (!g[l].sess)
951 continue;
952
953 cli_print(cli, "%7d %d.%d.%d.%d", g[l].sess, i, j, k, l);
954 ++count;
955 }
956 }
957 }
958 }
959 cli_print(cli, "%d entries in cache", count);
960 return CLI_OK;
961 }
962
963
964 // Find session by username, 0 for not found
965 // walled garden users aren't authenticated, so the username is
966 // reasonably useless. Ignore them to avoid incorrect actions
967 //
968 // This is VERY inefficent. Don't call it often. :)
969 //
970 sessionidt sessionbyuser(char *username)
971 {
972 int s;
973 CSTAT(sessionbyuser);
974
975 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
976 {
977 if (!session[s].opened)
978 continue;
979
980 if (session[s].walled_garden)
981 continue; // Skip walled garden users.
982
983 if (!strncmp(session[s].user, username, 128))
984 return s;
985
986 }
987 return 0; // Not found.
988 }
989
990 void send_garp(in_addr_t ip)
991 {
992 int s;
993 struct ifreq ifr;
994 uint8_t mac[6];
995
996 s = socket(PF_INET, SOCK_DGRAM, 0);
997 if (s < 0)
998 {
999 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
1000 return;
1001 }
1002 memset(&ifr, 0, sizeof(ifr));
1003 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
1004 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
1005 {
1006 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
1007 close(s);
1008 return;
1009 }
1010 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
1011 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
1012 {
1013 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
1014 close(s);
1015 return;
1016 }
1017 close(s);
1018 sendarp(ifr.ifr_ifindex, mac, ip);
1019 }
1020
1021 static sessiont *sessiontbysessionidt(sessionidt s)
1022 {
1023 if (!s || s >= MAXSESSION) return NULL;
1024 return &session[s];
1025 }
1026
1027 static sessionidt sessionidtbysessiont(sessiont *s)
1028 {
1029 sessionidt val = s-session;
1030 if (s < session || val >= MAXSESSION) return 0;
1031 return val;
1032 }
1033
1034 // actually send a control message for a specific tunnel
1035 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
1036 {
1037 struct sockaddr_in addr;
1038
1039 CSTAT(tunnelsend);
1040
1041 if (!t)
1042 {
1043 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
1044 STAT(tunnel_tx_errors);
1045 return;
1046 }
1047
1048 if (!tunnel[t].ip)
1049 {
1050 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
1051 STAT(tunnel_tx_errors);
1052 return;
1053 }
1054
1055 memset(&addr, 0, sizeof(addr));
1056 addr.sin_family = AF_INET;
1057 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
1058 addr.sin_port = htons(tunnel[t].port);
1059
1060 // sequence expected, if sequence in message
1061 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
1062
1063 // If this is a control message, deal with retries
1064 if (*buf & 0x80)
1065 {
1066 tunnel[t].last = time_now; // control message sent
1067 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
1068 if (tunnel[t].try)
1069 {
1070 STAT(tunnel_retries);
1071 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
1072 }
1073 }
1074
1075 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
1076 {
1077 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
1078 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
1079 STAT(tunnel_tx_errors);
1080 return;
1081 }
1082
1083 LOG_HEX(5, "Send Tunnel Data", buf, l);
1084 STAT(tunnel_tx_packets);
1085 INC_STAT(tunnel_tx_bytes, l);
1086 }
1087
1088 //
1089 // Tiny helper function to write data to
1090 // the 'tun' device.
1091 //
1092 int tun_write(uint8_t * data, int size)
1093 {
1094 return write(tunfd, data, size);
1095 }
1096
1097 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
1098 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
1099 {
1100 int d = (tcp[12] >> 4) * 4;
1101 uint8_t *mss = 0;
1102 uint8_t *opts;
1103 uint8_t *data;
1104 uint16_t orig;
1105 uint32_t sum;
1106
1107 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
1108 return;
1109
1110 if (tcp + d > buf + len) // short?
1111 return;
1112
1113 opts = tcp + 20;
1114 data = tcp + d;
1115
1116 while (opts < data)
1117 {
1118 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1119 {
1120 mss = opts + 2;
1121 if (mss + 2 > data) return; // short?
1122 break;
1123 }
1124
1125 if (*opts == 0) return; // end of options
1126 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1127 opts++;
1128 else
1129 opts += opts[1]; // skip over option
1130 }
1131
1132 if (!mss) return; // not found
1133 orig = ntohs(*(uint16_t *) mss);
1134
1135 if (orig <= MSS) return; // mss OK
1136
1137 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s: adjusted mss from %u to %u\n",
1138 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1139 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1140 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1141
1142 // set mss
1143 *(int16_t *) mss = htons(MSS);
1144
1145 // adjust checksum (see rfc1141)
1146 sum = orig + (~MSS & 0xffff);
1147 sum += ntohs(*(uint16_t *) (tcp + 16));
1148 sum = (sum & 0xffff) + (sum >> 16);
1149 *(uint16_t *) (tcp + 16) = htons(sum + (sum >> 16));
1150 }
1151
1152 void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra)
1153 {
1154 uint16_t proto;
1155 if (extra) {
1156 // Skip the four extra bytes
1157 p += 4;
1158 l -= 4;
1159 }
1160
1161 if (*p & 1)
1162 {
1163 proto = *p++;
1164 l--;
1165 }
1166 else
1167 {
1168 proto = ntohs(*(uint16_t *) p);
1169 p += 2;
1170 l -= 2;
1171 }
1172 if (proto == PPPIP)
1173 {
1174 if (session[s].die)
1175 {
1176 LOG(4, s, t, "MPPP: Session %d is closing. Don't process PPP packets\n", s);
1177 return; // closing session, PPP not processed
1178 }
1179 session[s].last_packet = session[s].last_data = time_now;
1180 processipin(s, t, p, l);
1181 }
1182 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
1183 {
1184 if (session[s].die)
1185 {
1186 LOG(4, s, t, "MPPP: Session %d is closing. Don't process PPP packets\n", s);
1187 return; // closing session, PPP not processed
1188 }
1189
1190 session[s].last_packet = session[s].last_data = time_now;
1191 processipv6in(s, t, p, l);
1192 }
1193 else if (proto == PPPIPCP)
1194 {
1195 session[s].last_packet = session[s].last_data = time_now;
1196 processipcp(s, t, p, l);
1197 }
1198 else if (proto == PPPCCP)
1199 {
1200 session[s].last_packet = session[s].last_data = time_now;
1201 processccp(s, t, p, l);
1202 }
1203 else
1204 {
1205 LOG(2, s, t, "MPPP: Unsupported MP protocol 0x%04X received\n",proto);
1206 }
1207 }
1208
1209 static void update_session_out_stat(sessionidt s, sessiont *sp, int len)
1210 {
1211 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1212 sp->cout_delta += len;
1213 sp->pout++;
1214 sp->last_data = time_now;
1215
1216 sess_local[s].cout += len; // To send to master..
1217 sess_local[s].pout++;
1218 }
1219
1220 // process outgoing (to tunnel) IP
1221 //
1222 static void processipout(uint8_t *buf, int len)
1223 {
1224 sessionidt s;
1225 sessiont *sp;
1226 tunnelidt t;
1227 in_addr_t ip;
1228
1229 uint8_t *data = buf; // Keep a copy of the originals.
1230 int size = len;
1231
1232 uint8_t fragbuf[MAXETHER + 20];
1233
1234 CSTAT(processipout);
1235
1236 if (len < MIN_IP_SIZE)
1237 {
1238 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1239 STAT(tun_rx_errors);
1240 return;
1241 }
1242 if (len >= MAXETHER)
1243 {
1244 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1245 STAT(tun_rx_errors);
1246 return;
1247 }
1248
1249 // Skip the tun header
1250 buf += 4;
1251 len -= 4;
1252
1253 // Got an IP header now
1254 if (*(uint8_t *)(buf) >> 4 != 4)
1255 {
1256 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1257 return;
1258 }
1259
1260 ip = *(uint32_t *)(buf + 16);
1261 if (!(s = sessionbyip(ip)))
1262 {
1263 // Is this a packet for a session that doesn't exist?
1264 static int rate = 0; // Number of ICMP packets we've sent this second.
1265 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1266
1267 if (last != time_now)
1268 {
1269 last = time_now;
1270 rate = 0;
1271 }
1272
1273 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1274 {
1275 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1276 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1277 config->bind_address ? config->bind_address : my_address, buf, len);
1278 }
1279 return;
1280 }
1281
1282 t = session[s].tunnel;
1283 if (len > session[s].mru || (session[s].mrru && len > session[s].mrru))
1284 {
1285 LOG(3, s, t, "Packet size more than session MRU\n");
1286 return;
1287 }
1288
1289 sp = &session[s];
1290
1291 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1292 if (config->max_packets > 0)
1293 {
1294 if (sess_local[s].last_packet_out == TIME)
1295 {
1296 int max = config->max_packets;
1297
1298 // All packets for throttled sessions are handled by the
1299 // master, so further limit by using the throttle rate.
1300 // A bit of a kludge, since throttle rate is in kbps,
1301 // but should still be generous given our average DSL
1302 // packet size is 200 bytes: a limit of 28kbps equates
1303 // to around 180 packets per second.
1304 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1305 max = sp->throttle_out;
1306
1307 if (++sess_local[s].packets_out > max)
1308 {
1309 sess_local[s].packets_dropped++;
1310 return;
1311 }
1312 }
1313 else
1314 {
1315 if (sess_local[s].packets_dropped)
1316 {
1317 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1318 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1319 sess_local[s].packets_dropped, sess_local[s].packets_out,
1320 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1321 sp->user);
1322 }
1323
1324 sess_local[s].last_packet_out = TIME;
1325 sess_local[s].packets_out = 1;
1326 sess_local[s].packets_dropped = 0;
1327 }
1328 }
1329
1330 // run access-list if any
1331 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1332 return;
1333
1334 // adjust MSS on SYN and SYN,ACK packets with options
1335 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1336 {
1337 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1338 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1339 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1340 }
1341
1342 if (sp->tbf_out)
1343 {
1344 // Are we throttling this session?
1345 if (config->cluster_iam_master)
1346 tbf_queue_packet(sp->tbf_out, data, size);
1347 else
1348 master_throttle_packet(sp->tbf_out, data, size);
1349 return;
1350 }
1351
1352 if (sp->walled_garden && !config->cluster_iam_master)
1353 {
1354 // We are walled-gardening this
1355 master_garden_packet(s, data, size);
1356 return;
1357 }
1358
1359 // Add on L2TP header
1360 {
1361 bundleidt bid = 0;
1362 if(session[s].bundle != 0 && bundle[session[s].bundle].num_of_links > 1)
1363 {
1364 bid = session[s].bundle;
1365 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1366 t = session[s].tunnel;
1367 sp = &session[s];
1368 LOG(4, s, t, "MPPP: (1)Session number becomes: %d\n", s);
1369 if(len > MINFRAGLEN)
1370 {
1371 // Partition the packet to "bundle[b].num_of_links" fragments
1372 bundlet *b = &bundle[bid];
1373 uint32_t num_of_links = b->num_of_links;
1374 uint32_t fraglen = len / num_of_links;
1375 fraglen = (fraglen > session[s].mru ? session[s].mru : fraglen);
1376 uint32_t last_fraglen = fraglen + len % num_of_links;
1377 last_fraglen = (last_fraglen > session[s].mru ? len % num_of_links : last_fraglen);
1378 uint32_t remain = len;
1379
1380 // send the first packet
1381 uint8_t *p = makeppp(fragbuf, sizeof(fragbuf), buf, fraglen, s, t, PPPIP, 0, bid, MP_BEGIN);
1382 if (!p) return;
1383 tunnelsend(fragbuf, fraglen + (p-fragbuf), t); // send it...
1384 // statistics
1385 update_session_out_stat(s, sp, fraglen);
1386 remain -= fraglen;
1387 while (remain > last_fraglen)
1388 {
1389 s = b->members[b->current_ses = ++b->current_ses % num_of_links];
1390 t = session[s].tunnel;
1391 sp = &session[s];
1392 LOG(4, s, t, "MPPP: (2)Session number becomes: %d\n", s);
1393 p = makeppp(fragbuf, sizeof(fragbuf), buf+(len - remain), fraglen, s, t, PPPIP, 0, bid, 0);
1394 if (!p) return;
1395 tunnelsend(fragbuf, fraglen + (p-fragbuf), t); // send it...
1396 update_session_out_stat(s, sp, fraglen);
1397 remain -= fraglen;
1398 }
1399 // send the last fragment
1400 s = b->members[b->current_ses = ++b->current_ses % num_of_links];
1401 t = session[s].tunnel;
1402 sp = &session[s];
1403 LOG(4, s, t, "MPPP: (2)Session number becomes: %d\n", s);
1404 p = makeppp(fragbuf, sizeof(fragbuf), buf+(len - remain), remain, s, t, PPPIP, 0, bid, MP_END);
1405 if (!p) return;
1406 tunnelsend(fragbuf, remain + (p-fragbuf), t); // send it...
1407 update_session_out_stat(s, sp, remain);
1408 if (remain != last_fraglen)
1409 LOG(3, s, t, "PROCESSIPOUT ERROR REMAIN != LAST_FRAGLEN, %d != %d\n", remain, last_fraglen);
1410 }
1411 else {
1412 // Send it as one frame
1413 uint8_t *p = makeppp(fragbuf, sizeof(fragbuf), buf, len, s, t, PPPIP, 0, bid, MP_BOTH_BITS);
1414 if (!p) return;
1415 tunnelsend(fragbuf, len + (p-fragbuf), t); // send it...
1416 LOG(4, s, t, "MPPP: packet sent as one frame\n");
1417 update_session_out_stat(s, sp, len);
1418 }
1419 }
1420 else
1421 {
1422 uint8_t *p = makeppp(fragbuf, sizeof(fragbuf), buf, len, s, t, PPPIP, 0, 0, 0);
1423 if (!p) return;
1424 tunnelsend(fragbuf, len + (p-fragbuf), t); // send it...
1425 update_session_out_stat(s, sp, len);
1426 }
1427 }
1428
1429 // Snooping this session, send it to intercept box
1430 if (sp->snoop_ip && sp->snoop_port)
1431 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1432
1433 udp_tx += len;
1434 }
1435
1436 // process outgoing (to tunnel) IPv6
1437 //
1438 static void processipv6out(uint8_t * buf, int len)
1439 {
1440 sessionidt s;
1441 sessiont *sp;
1442 tunnelidt t;
1443 in_addr_t ip;
1444 struct in6_addr ip6;
1445
1446 uint8_t *data = buf; // Keep a copy of the originals.
1447 int size = len;
1448
1449 uint8_t b[MAXETHER + 20];
1450
1451 CSTAT(processipv6out);
1452
1453 if (len < MIN_IP_SIZE)
1454 {
1455 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1456 STAT(tunnel_tx_errors);
1457 return;
1458 }
1459 if (len >= MAXETHER)
1460 {
1461 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1462 STAT(tunnel_tx_errors);
1463 return;
1464 }
1465
1466 // Skip the tun header
1467 buf += 4;
1468 len -= 4;
1469
1470 // Got an IP header now
1471 if (*(uint8_t *)(buf) >> 4 != 6)
1472 {
1473 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1474 return;
1475 }
1476
1477 ip6 = *(struct in6_addr *)(buf+24);
1478 s = sessionbyipv6(ip6);
1479
1480 if (s == 0)
1481 {
1482 ip = *(uint32_t *)(buf + 32);
1483 s = sessionbyip(ip);
1484 }
1485
1486 if (s == 0)
1487 {
1488 // Is this a packet for a session that doesn't exist?
1489 static int rate = 0; // Number of ICMP packets we've sent this second.
1490 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1491
1492 if (last != time_now)
1493 {
1494 last = time_now;
1495 rate = 0;
1496 }
1497
1498 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1499 {
1500 // FIXME: Should send icmp6 host unreachable
1501 }
1502 return;
1503 }
1504 if (session[s].bundle && bundle[session[s].bundle].num_of_links > 1)
1505 {
1506 bundleidt bid = session[s].bundle;
1507 s = bundle[bid].members[bundle[bid].current_ses = ++bundle[bid].current_ses % bundle[bid].num_of_links];
1508 LOG(3, s, session[s].tunnel, "MPPP: Session number becomes: %u\n", s);
1509 }
1510 t = session[s].tunnel;
1511 sp = &session[s];
1512 sp->last_data = time_now;
1513
1514 // FIXME: add DoS prevention/filters?
1515
1516 if (sp->tbf_out)
1517 {
1518 // Are we throttling this session?
1519 if (config->cluster_iam_master)
1520 tbf_queue_packet(sp->tbf_out, data, size);
1521 else
1522 master_throttle_packet(sp->tbf_out, data, size);
1523 return;
1524 }
1525 else if (sp->walled_garden && !config->cluster_iam_master)
1526 {
1527 // We are walled-gardening this
1528 master_garden_packet(s, data, size);
1529 return;
1530 }
1531
1532 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1533
1534 // Add on L2TP header
1535 {
1536 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6, 0, 0, 0);
1537 if (!p) return;
1538 tunnelsend(b, len + (p-b), t); // send it...
1539 }
1540
1541 // Snooping this session, send it to intercept box
1542 if (sp->snoop_ip && sp->snoop_port)
1543 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1544
1545 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1546 sp->cout_delta += len;
1547 sp->pout++;
1548 udp_tx += len;
1549
1550 sess_local[s].cout += len; // To send to master..
1551 sess_local[s].pout++;
1552 }
1553
1554 //
1555 // Helper routine for the TBF filters.
1556 // Used to send queued data in to the user!
1557 //
1558 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1559 {
1560 sessiont *sp;
1561 tunnelidt t;
1562 in_addr_t ip;
1563
1564 uint8_t b[MAXETHER + 20];
1565
1566 if (len < 0 || len > MAXETHER)
1567 {
1568 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1569 return;
1570 }
1571
1572 // Skip the tun header
1573 buf += 4;
1574 len -= 4;
1575
1576 ip = *(in_addr_t *)(buf + 16);
1577
1578 if (!session[s].ip)
1579 return;
1580
1581 t = session[s].tunnel;
1582 sp = &session[s];
1583
1584 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1585
1586 // Add on L2TP header
1587 {
1588 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP, 0, 0, 0);
1589 if (!p) return;
1590 tunnelsend(b, len + (p-b), t); // send it...
1591 }
1592
1593 // Snooping this session.
1594 if (sp->snoop_ip && sp->snoop_port)
1595 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1596
1597 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1598 sp->cout_delta += len;
1599 sp->pout++;
1600 udp_tx += len;
1601
1602 sess_local[s].cout += len; // To send to master..
1603 sess_local[s].pout++;
1604 }
1605
1606 // add an AVP (16 bit)
1607 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1608 {
1609 uint16_t l = (m ? 0x8008 : 0x0008);
1610 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1611 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1612 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1613 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1614 c->length += 8;
1615 }
1616
1617 // add an AVP (32 bit)
1618 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1619 {
1620 uint16_t l = (m ? 0x800A : 0x000A);
1621 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1622 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1623 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1624 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1625 c->length += 10;
1626 }
1627
1628 // add an AVP (string)
1629 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1630 {
1631 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1632 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1633 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1634 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1635 memcpy(c->buf + c->length + 6, val, strlen(val));
1636 c->length += 6 + strlen(val);
1637 }
1638
1639 // add a binary AVP
1640 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1641 {
1642 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1643 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1644 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1645 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1646 memcpy(c->buf + c->length + 6, val, len);
1647 c->length += 6 + len;
1648 }
1649
1650 // new control connection
1651 static controlt *controlnew(uint16_t mtype)
1652 {
1653 controlt *c;
1654 if (!controlfree)
1655 c = malloc(sizeof(controlt));
1656 else
1657 {
1658 c = controlfree;
1659 controlfree = c->next;
1660 }
1661 assert(c);
1662 c->next = 0;
1663 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1664 c->length = 12;
1665 control16(c, 0, mtype, 1);
1666 return c;
1667 }
1668
1669 // send zero block if nothing is waiting
1670 // (ZLB send).
1671 static void controlnull(tunnelidt t)
1672 {
1673 uint8_t buf[12];
1674 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1675 return;
1676
1677 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1678 *(uint16_t *) (buf + 2) = htons(12); // length
1679 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1680 *(uint16_t *) (buf + 6) = htons(0); // session
1681 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1682 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1683 tunnelsend(buf, 12, t);
1684 }
1685
1686 // add a control message to a tunnel, and send if within window
1687 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1688 {
1689 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1690 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1691 *(uint16_t *) (c->buf + 6) = htons(far); // session
1692 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1693 tunnel[t].ns++; // advance sequence
1694 // link in message in to queue
1695 if (tunnel[t].controlc)
1696 tunnel[t].controle->next = c;
1697 else
1698 tunnel[t].controls = c;
1699
1700 tunnel[t].controle = c;
1701 tunnel[t].controlc++;
1702
1703 // send now if space in window
1704 if (tunnel[t].controlc <= tunnel[t].window)
1705 {
1706 tunnel[t].try = 0; // first send
1707 tunnelsend(c->buf, c->length, t);
1708 }
1709 }
1710
1711 //
1712 // Throttle or Unthrottle a session
1713 //
1714 // Throttle the data from/to through a session to no more than
1715 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1716 // user).
1717 //
1718 // If either value is -1, the current value is retained for that
1719 // direction.
1720 //
1721 void throttle_session(sessionidt s, int rate_in, int rate_out)
1722 {
1723 if (!session[s].opened)
1724 return; // No-one home.
1725
1726 if (!*session[s].user)
1727 return; // User not logged in
1728
1729 if (rate_in >= 0)
1730 {
1731 int bytes = rate_in * 1024 / 8; // kbits to bytes
1732 if (session[s].tbf_in)
1733 free_tbf(session[s].tbf_in);
1734
1735 if (rate_in > 0)
1736 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1737 else
1738 session[s].tbf_in = 0;
1739
1740 session[s].throttle_in = rate_in;
1741 }
1742
1743 if (rate_out >= 0)
1744 {
1745 int bytes = rate_out * 1024 / 8;
1746 if (session[s].tbf_out)
1747 free_tbf(session[s].tbf_out);
1748
1749 if (rate_out > 0)
1750 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1751 else
1752 session[s].tbf_out = 0;
1753
1754 session[s].throttle_out = rate_out;
1755 }
1756 }
1757
1758 // add/remove filters from session (-1 = no change)
1759 void filter_session(sessionidt s, int filter_in, int filter_out)
1760 {
1761 if (!session[s].opened)
1762 return; // No-one home.
1763
1764 if (!*session[s].user)
1765 return; // User not logged in
1766
1767 // paranoia
1768 if (filter_in > MAXFILTER) filter_in = -1;
1769 if (filter_out > MAXFILTER) filter_out = -1;
1770 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1771 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1772
1773 if (filter_in >= 0)
1774 {
1775 if (session[s].filter_in)
1776 ip_filters[session[s].filter_in - 1].used--;
1777
1778 if (filter_in > 0)
1779 ip_filters[filter_in - 1].used++;
1780
1781 session[s].filter_in = filter_in;
1782 }
1783
1784 if (filter_out >= 0)
1785 {
1786 if (session[s].filter_out)
1787 ip_filters[session[s].filter_out - 1].used--;
1788
1789 if (filter_out > 0)
1790 ip_filters[filter_out - 1].used++;
1791
1792 session[s].filter_out = filter_out;
1793 }
1794 }
1795
1796 // start tidy shutdown of session
1797 void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause)
1798 {
1799 int walled_garden = session[s].walled_garden;
1800 bundleidt b = session[s].bundle;
1801 //delete routes only for last session in bundle (in case of MPPP)
1802 int del_routes = !b || (bundle[b].num_of_links == 1);
1803
1804 CSTAT(sessionshutdown);
1805
1806 if (!session[s].opened)
1807 {
1808 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1809 return; // not a live session
1810 }
1811
1812 if (!session[s].die)
1813 {
1814 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1815 LOG(2, s, session[s].tunnel, "Shutting down session %u: %s\n", s, reason);
1816 run_plugins(PLUGIN_KILL_SESSION, &data);
1817 session[s].die = TIME + 150; // Clean up in 15 seconds
1818 }
1819
1820 if (session[s].ip && !walled_garden && !session[s].die)
1821 {
1822 // RADIUS Stop message
1823 uint16_t r = radiusnew(s);
1824 if (r)
1825 {
1826 // stop, if not already trying
1827 if (radius[r].state != RADIUSSTOP)
1828 {
1829 radius[r].term_cause = term_cause;
1830 radius[r].term_msg = reason;
1831 radiussend(r, RADIUSSTOP);
1832 }
1833 }
1834 else
1835 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1836
1837 // Save counters to dump to accounting file
1838 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1839 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1840 }
1841
1842 if (session[s].ip)
1843 { // IP allocated, clear and unroute
1844 int r;
1845 int routed = 0;
1846 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1847 {
1848 if ((session[s].ip & session[s].route[r].mask) ==
1849 (session[s].route[r].ip & session[s].route[r].mask))
1850 routed++;
1851
1852 if (del_routes) routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1853 session[s].route[r].ip = 0;
1854 }
1855
1856 if (session[s].ip_pool_index == -1) // static ip
1857 {
1858 if (!routed && del_routes) routeset(s, session[s].ip, 0, 0, 0);
1859 session[s].ip = 0;
1860 }
1861 else
1862 free_ip_address(s);
1863
1864 // unroute IPv6, if setup
1865 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen && del_routes)
1866 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1867
1868 if (b)
1869 {
1870 // This session was part of a bundle
1871 bundle[b].num_of_links--;
1872 LOG(3, s, 0, "MPPP: Dropping member link: %d from bundle %d\n",s,b);
1873 if(bundle[b].num_of_links == 0)
1874 {
1875 bundleclear(b);
1876 LOG(3, s, 0, "MPPP: Kill bundle: %d (No remaing member links)\n",b);
1877 }
1878 else
1879 {
1880 // Adjust the members array to accomodate the new change
1881 uint8_t mem_num = 0;
1882 // It should be here num_of_links instead of num_of_links-1 (previous instruction "num_of_links--")
1883 if(bundle[b].members[bundle[b].num_of_links] != s)
1884 {
1885 uint8_t ml;
1886 for(ml = 0; ml<bundle[b].num_of_links; ml++)
1887 if(bundle[b].members[ml] == s)
1888 {
1889 mem_num = ml;
1890 break;
1891 }
1892 bundle[b].members[mem_num] = bundle[b].members[bundle[b].num_of_links];
1893 LOG(3, s, 0, "MPPP: Adjusted member links array\n");
1894 }
1895 }
1896 cluster_send_bundle(b);
1897 }
1898 }
1899
1900 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1901 throttle_session(s, 0, 0);
1902
1903 if (cdn_result)
1904 { // Send CDN
1905 controlt *c = controlnew(14); // sending CDN
1906 if (cdn_error)
1907 {
1908 uint8_t buf[4];
1909 *(uint16_t *) buf = htons(cdn_result);
1910 *(uint16_t *) (buf+2) = htons(cdn_error);
1911 controlb(c, 1, buf, 4, 1);
1912 }
1913 else
1914 control16(c, 1, cdn_result, 1);
1915
1916 control16(c, 14, s, 1); // assigned session (our end)
1917 controladd(c, session[s].far, session[s].tunnel); // send the message
1918 }
1919
1920 // update filter refcounts
1921 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1922 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1923
1924 // clear PPP state
1925 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1926 sess_local[s].lcp.restart = 0;
1927 sess_local[s].ipcp.restart = 0;
1928 sess_local[s].ipv6cp.restart = 0;
1929 sess_local[s].ccp.restart = 0;
1930
1931 cluster_send_session(s);
1932 }
1933
1934 void sendipcp(sessionidt s, tunnelidt t)
1935 {
1936 uint8_t buf[MAXETHER];
1937 uint8_t *q;
1938
1939 CSTAT(sendipcp);
1940 LOG(3, s, t, "IPCP: send ConfigReq\n");
1941
1942 if (!session[s].unique_id)
1943 {
1944 if (!++last_id) ++last_id; // skip zero
1945 session[s].unique_id = last_id;
1946 }
1947
1948 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP, 0, 0, 0);
1949 if (!q) return;
1950
1951 *q = ConfigReq;
1952 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1953 *(uint16_t *) (q + 2) = htons(10); // packet length
1954 q[4] = 3; // ip address option
1955 q[5] = 6; // option length
1956 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1957 config->bind_address ? config->bind_address :
1958 my_address; // send my IP
1959
1960 tunnelsend(buf, 10 + (q - buf), t); // send it
1961 restart_timer(s, ipcp);
1962 }
1963
1964 void sendipv6cp(sessionidt s, tunnelidt t)
1965 {
1966 uint8_t buf[MAXETHER];
1967 uint8_t *q;
1968
1969 CSTAT(sendipv6cp);
1970 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1971
1972 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP, 0, 0, 0);
1973 if (!q) return;
1974
1975 *q = ConfigReq;
1976 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1977 // only send one type
1978 // of request
1979 *(uint16_t *) (q + 2) = htons(14);
1980 q[4] = 1; // interface identifier option
1981 q[5] = 10; // option length
1982 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1983 *(uint32_t *) (q + 10) = 0;
1984 q[13] = 1;
1985
1986 tunnelsend(buf, 14 + (q - buf), t); // send it
1987 restart_timer(s, ipv6cp);
1988 }
1989
1990 static void sessionclear(sessionidt s)
1991 {
1992 memset(&session[s], 0, sizeof(session[s]));
1993 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1994 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1995
1996 session[s].tunnel = T_FREE; // Mark it as free.
1997 session[s].next = sessionfree;
1998 sessionfree = s;
1999 }
2000
2001 // kill a session now
2002 void sessionkill(sessionidt s, char *reason)
2003 {
2004 CSTAT(sessionkill);
2005
2006 if (!session[s].opened) // not alive
2007 return;
2008
2009 if (session[s].next)
2010 {
2011 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%u)\n", session[s].next);
2012 return;
2013 }
2014
2015 if (!session[s].die)
2016 sessionshutdown(s, reason, CDN_ADMIN_DISC, TERM_ADMIN_RESET); // close radius/routes, etc.
2017
2018 if (sess_local[s].radius)
2019 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
2020
2021 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
2022 sessionclear(s);
2023 cluster_send_session(s);
2024 }
2025
2026 static void tunnelclear(tunnelidt t)
2027 {
2028 if (!t) return;
2029 memset(&tunnel[t], 0, sizeof(tunnel[t]));
2030 tunnel[t].state = TUNNELFREE;
2031 }
2032
2033 static void bundleclear(bundleidt b)
2034 {
2035 if (!b) return;
2036 memset(&bundle[b], 0, sizeof(bundle[b]));
2037 bundle[b].state = BUNDLEFREE;
2038 }
2039
2040 // kill a tunnel now
2041 static void tunnelkill(tunnelidt t, char *reason)
2042 {
2043 sessionidt s;
2044 controlt *c;
2045
2046 CSTAT(tunnelkill);
2047
2048 tunnel[t].state = TUNNELDIE;
2049
2050 // free control messages
2051 while ((c = tunnel[t].controls))
2052 {
2053 controlt * n = c->next;
2054 tunnel[t].controls = n;
2055 tunnel[t].controlc--;
2056 c->next = controlfree;
2057 controlfree = c;
2058 }
2059 // kill sessions
2060 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
2061 if (session[s].tunnel == t)
2062 sessionkill(s, reason);
2063
2064 // free tunnel
2065 tunnelclear(t);
2066 LOG(1, 0, t, "Kill tunnel %u: %s\n", t, reason);
2067 cli_tunnel_actions[t].action = 0;
2068 cluster_send_tunnel(t);
2069 }
2070
2071 // shut down a tunnel cleanly
2072 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
2073 {
2074 sessionidt s;
2075
2076 CSTAT(tunnelshutdown);
2077
2078 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
2079 {
2080 // never set up, can immediately kill
2081 tunnelkill(t, reason);
2082 return;
2083 }
2084 LOG(1, 0, t, "Shutting down tunnel %u (%s)\n", t, reason);
2085
2086 // close session
2087 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
2088 if (session[s].tunnel == t)
2089 sessionshutdown(s, reason, CDN_NONE, TERM_ADMIN_RESET);
2090
2091 tunnel[t].state = TUNNELDIE;
2092 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
2093 cluster_send_tunnel(t);
2094 // TBA - should we wait for sessions to stop?
2095 if (result)
2096 {
2097 controlt *c = controlnew(4); // sending StopCCN
2098 if (error)
2099 {
2100 uint8_t buf[64];
2101 int l = 4;
2102 *(uint16_t *) buf = htons(result);
2103 *(uint16_t *) (buf+2) = htons(error);
2104 if (msg)
2105 {
2106 int m = strlen(msg);
2107 if (m + 4 > sizeof(buf))
2108 m = sizeof(buf) - 4;
2109
2110 memcpy(buf+4, msg, m);
2111 l += m;
2112 }
2113
2114 controlb(c, 1, buf, l, 1);
2115 }
2116 else
2117 control16(c, 1, result, 1);
2118
2119 control16(c, 9, t, 1); // assigned tunnel (our end)
2120 controladd(c, 0, t); // send the message
2121 }
2122 }
2123
2124 // read and process packet on tunnel (UDP)
2125 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
2126 {
2127 uint8_t *chapresponse = NULL;
2128 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
2129 uint8_t *p = buf + 2;
2130
2131
2132 CSTAT(processudp);
2133
2134 udp_rx += len;
2135 udp_rx_pkt++;
2136 LOG_HEX(5, "UDP Data", buf, len);
2137 STAT(tunnel_rx_packets);
2138 INC_STAT(tunnel_rx_bytes, len);
2139 if (len < 6)
2140 {
2141 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
2142 STAT(tunnel_rx_errors);
2143 return;
2144 }
2145 if ((buf[1] & 0x0F) != 2)
2146 {
2147 LOG(1, 0, 0, "Bad L2TP ver %d\n", buf[1] & 0x0F);
2148 STAT(tunnel_rx_errors);
2149 return;
2150 }
2151 if (*buf & 0x40)
2152 { // length
2153 l = ntohs(*(uint16_t *) p);
2154 p += 2;
2155 }
2156 t = ntohs(*(uint16_t *) p);
2157 p += 2;
2158 s = ntohs(*(uint16_t *) p);
2159 p += 2;
2160 if (s >= MAXSESSION)
2161 {
2162 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
2163 STAT(tunnel_rx_errors);
2164 return;
2165 }
2166 if (t >= MAXTUNNEL)
2167 {
2168 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
2169 STAT(tunnel_rx_errors);
2170 return;
2171 }
2172 if (*buf & 0x08)
2173 { // ns/nr
2174 ns = ntohs(*(uint16_t *) p);
2175 p += 2;
2176 nr = ntohs(*(uint16_t *) p);
2177 p += 2;
2178 }
2179 if (*buf & 0x02)
2180 { // offset
2181 uint16_t o = ntohs(*(uint16_t *) p);
2182 p += o + 2;
2183 }
2184 if ((p - buf) > l)
2185 {
2186 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
2187 STAT(tunnel_rx_errors);
2188 return;
2189 }
2190 l -= (p - buf);
2191
2192 // used to time out old tunnels
2193 if (t && tunnel[t].state == TUNNELOPEN)
2194 tunnel[t].lastrec = time_now;
2195
2196 if (*buf & 0x80)
2197 { // control
2198 uint16_t message = 0xFFFF; // message type
2199 uint8_t fatal = 0;
2200 uint8_t mandatory = 0;
2201 uint16_t asession = 0; // assigned session
2202 uint32_t amagic = 0; // magic number
2203 uint8_t aflags = 0; // flags from last LCF
2204 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
2205 char called[MAXTEL] = ""; // called number
2206 char calling[MAXTEL] = ""; // calling number
2207
2208 if (!config->cluster_iam_master)
2209 {
2210 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2211 return;
2212 }
2213
2214 // control messages must have bits 0x80|0x40|0x08
2215 // (type, length and sequence) set, and bits 0x02|0x01
2216 // (offset and priority) clear
2217 if ((*buf & 0xCB) != 0xC8)
2218 {
2219 LOG(1, s, t, "Bad control header %02X\n", *buf);
2220 STAT(tunnel_rx_errors);
2221 return;
2222 }
2223
2224 // check for duplicate tunnel open message
2225 if (!t && ns == 0)
2226 {
2227 int i;
2228
2229 //
2230 // Is this a duplicate of the first packet? (SCCRQ)
2231 //
2232 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
2233 {
2234 if (tunnel[i].state != TUNNELOPENING ||
2235 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
2236 tunnel[i].port != ntohs(addr->sin_port) )
2237 continue;
2238 t = i;
2239 LOG(3, s, t, "Duplicate SCCRQ?\n");
2240 break;
2241 }
2242 }
2243
2244 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %u l-nr %u r-ns %u r-nr %u\n",
2245 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
2246
2247 // if no tunnel specified, assign one
2248 if (!t)
2249 {
2250 if (!(t = new_tunnel()))
2251 {
2252 LOG(1, 0, 0, "No more tunnels\n");
2253 STAT(tunnel_overflow);
2254 return;
2255 }
2256 tunnelclear(t);
2257 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
2258 tunnel[t].port = ntohs(addr->sin_port);
2259 tunnel[t].window = 4; // default window
2260 STAT(tunnel_created);
2261 LOG(1, 0, t, " New tunnel from %s:%u ID %u\n",
2262 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
2263 }
2264
2265 // If the 'ns' just received is not the 'nr' we're
2266 // expecting, just send an ack and drop it.
2267 //
2268 // if 'ns' is less, then we got a retransmitted packet.
2269 // if 'ns' is greater than missed a packet. Either way
2270 // we should ignore it.
2271 if (ns != tunnel[t].nr)
2272 {
2273 // is this the sequence we were expecting?
2274 STAT(tunnel_rx_errors);
2275 LOG(1, 0, t, " Out of sequence tunnel %u, (%u is not the expected %u)\n",
2276 t, ns, tunnel[t].nr);
2277
2278 if (l) // Is this not a ZLB?
2279 controlnull(t);
2280 return;
2281 }
2282
2283 // check sequence of this message
2284 {
2285 int skip = tunnel[t].window; // track how many in-window packets are still in queue
2286 // some to clear maybe?
2287 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
2288 {
2289 controlt *c = tunnel[t].controls;
2290 tunnel[t].controls = c->next;
2291 tunnel[t].controlc--;
2292 c->next = controlfree;
2293 controlfree = c;
2294 skip--;
2295 tunnel[t].try = 0; // we have progress
2296 }
2297
2298 // receiver advance (do here so quoted correctly in any sends below)
2299 if (l) tunnel[t].nr = (ns + 1);
2300 if (skip < 0) skip = 0;
2301 if (skip < tunnel[t].controlc)
2302 {
2303 // some control packets can now be sent that were previous stuck out of window
2304 int tosend = tunnel[t].window - skip;
2305 controlt *c = tunnel[t].controls;
2306 while (c && skip)
2307 {
2308 c = c->next;
2309 skip--;
2310 }
2311 while (c && tosend)
2312 {
2313 tunnel[t].try = 0; // first send
2314 tunnelsend(c->buf, c->length, t);
2315 c = c->next;
2316 tosend--;
2317 }
2318 }
2319 if (!tunnel[t].controlc)
2320 tunnel[t].retry = 0; // caught up
2321 }
2322 if (l)
2323 { // if not a null message
2324 int result = 0;
2325 int error = 0;
2326 char *msg = 0;
2327
2328 // Default disconnect cause/message on receipt of CDN. Set to
2329 // more specific value from attribute 1 (result code) or 46
2330 // (disconnect cause) if present below.
2331 int disc_cause_set = 0;
2332 int disc_cause = TERM_NAS_REQUEST;
2333 char const *disc_reason = "Closed (Received CDN).";
2334
2335 // process AVPs
2336 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2337 {
2338 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2339 uint8_t *b = p;
2340 uint8_t flags = *p;
2341 uint16_t mtype;
2342
2343 if (n > l)
2344 {
2345 LOG(1, s, t, "Invalid length in AVP\n");
2346 STAT(tunnel_rx_errors);
2347 return;
2348 }
2349 p += n; // next
2350 l -= n;
2351 if (flags & 0x3C) // reserved bits, should be clear
2352 {
2353 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2354 fatal = flags;
2355 result = 2; // general error
2356 error = 3; // reserved field non-zero
2357 msg = 0;
2358 continue; // next
2359 }
2360 b += 2;
2361 if (*(uint16_t *) (b))
2362 {
2363 LOG(2, s, t, "Unknown AVP vendor %u\n", ntohs(*(uint16_t *) (b)));
2364 fatal = flags;
2365 result = 2; // general error
2366 error = 6; // generic vendor-specific error
2367 msg = "unsupported vendor-specific";
2368 continue; // next
2369 }
2370 b += 2;
2371 mtype = ntohs(*(uint16_t *) (b));
2372 b += 2;
2373 n -= 6;
2374
2375 if (flags & 0x40)
2376 {
2377 uint16_t orig_len;
2378
2379 // handle hidden AVPs
2380 if (!*config->l2tp_secret)
2381 {
2382 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2383 fatal = flags;
2384 result = 2; // general error
2385 error = 6; // generic vendor-specific error
2386 msg = "secret not specified";
2387 continue;
2388 }
2389 if (!session[s].random_vector_length)
2390 {
2391 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2392 fatal = flags;
2393 result = 2; // general error
2394 error = 6; // generic
2395 msg = "no random vector";
2396 continue;
2397 }
2398 if (n < 8)
2399 {
2400 LOG(2, s, t, "Short hidden AVP.\n");
2401 fatal = flags;
2402 result = 2; // general error
2403 error = 2; // length is wrong
2404 msg = 0;
2405 continue;
2406 }
2407
2408 // Unhide the AVP
2409 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2410
2411 orig_len = ntohs(*(uint16_t *) b);
2412 if (orig_len > n + 2)
2413 {
2414 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2415 orig_len, n);
2416
2417 fatal = flags;
2418 result = 2; // general error
2419 error = 2; // length is wrong
2420 msg = 0;
2421 continue;
2422 }
2423
2424 b += 2;
2425 n = orig_len;
2426 }
2427
2428 LOG(4, s, t, " AVP %u (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2429 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2430
2431 switch (mtype)
2432 {
2433 case 0: // message type
2434 message = ntohs(*(uint16_t *) b);
2435 mandatory = flags & 0x80;
2436 LOG(4, s, t, " Message type = %u (%s)\n", *b, l2tp_code(message));
2437 break;
2438 case 1: // result code
2439 {
2440 uint16_t rescode = ntohs(*(uint16_t *) b);
2441 char const *resdesc = "(unknown)";
2442 char const *errdesc = NULL;
2443 int cause = 0;
2444
2445 if (message == 4)
2446 { /* StopCCN */
2447 resdesc = l2tp_stopccn_result_code(rescode);
2448 cause = TERM_LOST_SERVICE;
2449 }
2450 else if (message == 14)
2451 { /* CDN */
2452 resdesc = l2tp_cdn_result_code(rescode);
2453 if (rescode == 1)
2454 cause = TERM_LOST_CARRIER;
2455 else
2456 cause = TERM_ADMIN_RESET;
2457 }
2458
2459 LOG(4, s, t, " Result Code %u: %s\n", rescode, resdesc);
2460 if (n >= 4)
2461 {
2462 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2463 errdesc = l2tp_error_code(errcode);
2464 LOG(4, s, t, " Error Code %u: %s\n", errcode, errdesc);
2465 }
2466 if (n > 4)
2467 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2468
2469 if (cause && disc_cause_set < mtype) // take cause from attrib 46 in preference
2470 {
2471 disc_cause_set = mtype;
2472 disc_reason = errdesc ? errdesc : resdesc;
2473 disc_cause = cause;
2474 }
2475
2476 break;
2477 }
2478 break;
2479 case 2: // protocol version
2480 {
2481 version = ntohs(*(uint16_t *) (b));
2482 LOG(4, s, t, " Protocol version = %u\n", version);
2483 if (version && version != 0x0100)
2484 { // allow 0.0 and 1.0
2485 LOG(1, s, t, " Bad protocol version %04X\n", version);
2486 fatal = flags;
2487 result = 5; // unspported protocol version
2488 error = 0x0100; // supported version
2489 msg = 0;
2490 continue; // next
2491 }
2492 }
2493 break;
2494 case 3: // framing capabilities
2495 break;
2496 case 4: // bearer capabilities
2497 break;
2498 case 5: // tie breaker
2499 // We never open tunnels, so we don't care about tie breakers
2500 continue;
2501 case 6: // firmware revision
2502 break;
2503 case 7: // host name
2504 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2505 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2506 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2507 // TBA - to send to RADIUS
2508 break;
2509 case 8: // vendor name
2510 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2511 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2512 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2513 break;
2514 case 9: // assigned tunnel
2515 tunnel[t].far = ntohs(*(uint16_t *) (b));
2516 LOG(4, s, t, " Remote tunnel id = %u\n", tunnel[t].far);
2517 break;
2518 case 10: // rx window
2519 tunnel[t].window = ntohs(*(uint16_t *) (b));
2520 if (!tunnel[t].window)
2521 tunnel[t].window = 1; // window of 0 is silly
2522 LOG(4, s, t, " rx window = %u\n", tunnel[t].window);
2523 break;
2524 case 11: // Challenge
2525 {
2526 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2527 build_chap_response(b, 2, n, &chapresponse);
2528 }
2529 break;
2530 case 13: // Response
2531 // Why did they send a response? We never challenge.
2532 LOG(2, s, t, " received unexpected challenge response\n");
2533 break;
2534
2535 case 14: // assigned session
2536 asession = session[s].far = ntohs(*(uint16_t *) (b));
2537 LOG(4, s, t, " assigned session = %u\n", asession);
2538 break;
2539 case 15: // call serial number
2540 LOG(4, s, t, " call serial number = %u\n", ntohl(*(uint32_t *)b));
2541 break;
2542 case 18: // bearer type
2543 LOG(4, s, t, " bearer type = %u\n", ntohl(*(uint32_t *)b));
2544 // TBA - for RADIUS
2545 break;
2546 case 19: // framing type
2547 LOG(4, s, t, " framing type = %u\n", ntohl(*(uint32_t *)b));
2548 // TBA
2549 break;
2550 case 21: // called number
2551 memset(called, 0, sizeof(called));
2552 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2553 LOG(4, s, t, " Called <%s>\n", called);
2554 break;
2555 case 22: // calling number
2556 memset(calling, 0, sizeof(calling));
2557 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2558 LOG(4, s, t, " Calling <%s>\n", calling);
2559 break;
2560 case 23: // subtype
2561 break;
2562 case 24: // tx connect speed
2563 if (n == 4)
2564 {
2565 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2566 }
2567 else
2568 {
2569 // AS5300s send connect speed as a string
2570 char tmp[30];
2571 memset(tmp, 0, sizeof(tmp));
2572 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2573 session[s].tx_connect_speed = atol(tmp);
2574 }
2575 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2576 break;
2577 case 38: // rx connect speed
2578 if (n == 4)
2579 {
2580 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2581 }
2582 else
2583 {
2584 // AS5300s send connect speed as a string
2585 char tmp[30];
2586 memset(tmp, 0, sizeof(tmp));
2587 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2588 session[s].rx_connect_speed = atol(tmp);
2589 }
2590 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2591 break;
2592 case 25: // Physical Channel ID
2593 {
2594 uint32_t tmp = ntohl(*(uint32_t *) b);
2595 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2596 break;
2597 }
2598 case 29: // Proxy Authentication Type
2599 {
2600 uint16_t atype = ntohs(*(uint16_t *)b);
2601 LOG(4, s, t, " Proxy Auth Type %u (%s)\n", atype, ppp_auth_type(atype));
2602 break;
2603 }
2604 case 30: // Proxy Authentication Name
2605 {
2606 char authname[64];
2607 memset(authname, 0, sizeof(authname));
2608 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2609 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2610 authname);
2611 break;
2612 }
2613 case 31: // Proxy Authentication Challenge
2614 {
2615 LOG(4, s, t, " Proxy Auth Challenge\n");
2616 break;
2617 }
2618 case 32: // Proxy Authentication ID
2619 {
2620 uint16_t authid = ntohs(*(uint16_t *)(b));
2621 LOG(4, s, t, " Proxy Auth ID (%u)\n", authid);
2622 break;
2623 }
2624 case 33: // Proxy Authentication Response
2625 LOG(4, s, t, " Proxy Auth Response\n");
2626 break;
2627 case 27: // last sent lcp
2628 { // find magic number
2629 uint8_t *p = b, *e = p + n;
2630 while (p + 1 < e && p[1] && p + p[1] <= e)
2631 {
2632 if (*p == 5 && p[1] == 6) // Magic-Number
2633 amagic = ntohl(*(uint32_t *) (p + 2));
2634 else if (*p == 7) // Protocol-Field-Compression
2635 aflags |= SESSION_PFC;
2636 else if (*p == 8) // Address-and-Control-Field-Compression
2637 aflags |= SESSION_ACFC;
2638 p += p[1];
2639 }
2640 }
2641 break;
2642 case 28: // last recv lcp confreq
2643 break;
2644 case 26: // Initial Received LCP CONFREQ
2645 break;
2646 case 39: // seq required - we control it as an LNS anyway...
2647 break;
2648 case 36: // Random Vector
2649 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2650 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2651 if (n > sizeof(session[s].random_vector))
2652 n = sizeof(session[s].random_vector);
2653 memcpy(session[s].random_vector, b, n);
2654 session[s].random_vector_length = n;
2655 break;
2656 case 46: // ppp disconnect cause
2657 if (n >= 5)
2658 {
2659 uint16_t code = ntohs(*(uint16_t *) b);
2660 uint16_t proto = ntohs(*(uint16_t *) (b + 2));
2661 uint8_t dir = *(b + 4);
2662
2663 LOG(4, s, t, " PPP disconnect cause "
2664 "(code=%u, proto=%04X, dir=%u, msg=\"%.*s\")\n",
2665 code, proto, dir, n - 5, b + 5);
2666
2667 disc_cause_set = mtype;
2668
2669 switch (code)
2670 {
2671 case 1: // admin disconnect
2672 disc_cause = TERM_ADMIN_RESET;
2673 disc_reason = "Administrative disconnect";
2674 break;
2675 case 3: // lcp terminate
2676 if (dir != 2) break; // 1=peer (LNS), 2=local (LAC)
2677 disc_cause = TERM_USER_REQUEST;
2678 disc_reason = "Normal disconnection";
2679 break;
2680 case 4: // compulsory encryption unavailable
2681 if (dir != 1) break; // 1=refused by peer, 2=local
2682 disc_cause = TERM_USER_ERROR;
2683 disc_reason = "Compulsory encryption refused";
2684 break;
2685 case 5: // lcp: fsm timeout
2686 disc_cause = TERM_PORT_ERROR;
2687 disc_reason = "LCP: FSM timeout";
2688 break;
2689 case 6: // lcp: no recognisable lcp packets received
2690 disc_cause = TERM_PORT_ERROR;
2691 disc_reason = "LCP: no recognisable LCP packets";
2692 break;
2693 case 7: // lcp: magic-no error (possibly looped back)
2694 disc_cause = TERM_PORT_ERROR;
2695 disc_reason = "LCP: magic-no error (possible loop)";
2696 break;
2697 case 8: // lcp: echo request timeout
2698 disc_cause = TERM_PORT_ERROR;
2699 disc_reason = "LCP: echo request timeout";
2700 break;
2701 case 13: // auth: fsm timeout
2702 disc_cause = TERM_SERVICE_UNAVAILABLE;
2703 disc_reason = "Authentication: FSM timeout";
2704 break;
2705 case 15: // auth: unacceptable auth protocol
2706 disc_cause = TERM_SERVICE_UNAVAILABLE;
2707 disc_reason = "Unacceptable authentication protocol";
2708 break;
2709 case 16: // auth: authentication failed
2710 disc_cause = TERM_SERVICE_UNAVAILABLE;
2711 disc_reason = "Authentication failed";
2712 break;
2713 case 17: // ncp: fsm timeout
2714 disc_cause = TERM_SERVICE_UNAVAILABLE;
2715 disc_reason = "NCP: FSM timeout";
2716 break;
2717 case 18: // ncp: no ncps available
2718 disc_cause = TERM_SERVICE_UNAVAILABLE;
2719 disc_reason = "NCP: no NCPs available";
2720 break;
2721 case 19: // ncp: failure to converge on acceptable address
2722 disc_cause = TERM_SERVICE_UNAVAILABLE;
2723 disc_reason = (dir == 1)
2724 ? "NCP: too many Configure-Naks received from peer"
2725 : "NCP: too many Configure-Naks sent to peer";
2726 break;
2727 case 20: // ncp: user not permitted to use any address
2728 disc_cause = TERM_SERVICE_UNAVAILABLE;
2729 disc_reason = (dir == 1)
2730 ? "NCP: local link address not acceptable to peer"
2731 : "NCP: remote link address not acceptable";
2732 break;
2733 }
2734 }
2735 break;
2736 default:
2737 {
2738 static char e[] = "unknown AVP 0xXXXX";
2739 LOG(2, s, t, " Unknown AVP type %u\n", mtype);
2740 fatal = flags;
2741 result = 2; // general error
2742 error = 8; // unknown mandatory AVP
2743 sprintf((msg = e) + 14, "%04x", mtype);
2744 continue; // next
2745 }
2746 }
2747 }
2748 // process message
2749 if (fatal & 0x80)
2750 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2751 else
2752 switch (message)
2753 {
2754 case 1: // SCCRQ - Start Control Connection Request
2755 tunnel[t].state = TUNNELOPENING;
2756 if (main_quit != QUIT_SHUTDOWN)
2757 {
2758 controlt *c = controlnew(2); // sending SCCRP
2759 control16(c, 2, version, 1); // protocol version
2760 control32(c, 3, 3, 1); // framing
2761 controls(c, 7, hostname, 1); // host name
2762 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2763 control16(c, 9, t, 1); // assigned tunnel
2764 controladd(c, 0, t); // send the resply
2765 }
2766 else
2767 {
2768 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2769 }
2770 break;
2771 case 2: // SCCRP
2772 tunnel[t].state = TUNNELOPEN;
2773 tunnel[t].lastrec = time_now;
2774 break;
2775 case 3: // SCCN
2776 tunnel[t].state = TUNNELOPEN;
2777 tunnel[t].lastrec = time_now;
2778 controlnull(t); // ack
2779 break;
2780 case 4: // StopCCN
2781 controlnull(t); // ack
2782 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2783 break;
2784 case 6: // HELLO
2785 controlnull(t); // simply ACK
2786 break;
2787 case 7: // OCRQ
2788 // TBA
2789 break;
2790 case 8: // OCRO
2791 // TBA
2792 break;
2793 case 9: // OCCN
2794 // TBA
2795 break;
2796 case 10: // ICRQ
2797 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2798 {
2799 controlt *c = controlnew(11); // ICRP
2800
2801 s = sessionfree;
2802 sessionfree = session[s].next;
2803 memset(&session[s], 0, sizeof(session[s]));
2804
2805 if (s > config->cluster_highest_sessionid)
2806 config->cluster_highest_sessionid = s;
2807
2808 session[s].opened = time_now;
2809 session[s].tunnel = t;
2810 session[s].far = asession;
2811 session[s].last_packet = session[s].last_data = time_now;
2812 LOG(3, s, t, "New session (%u/%u)\n", tunnel[t].far, session[s].far);
2813 control16(c, 14, s, 1); // assigned session
2814 controladd(c, asession, t); // send the reply
2815
2816 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2817 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2818
2819 session[s].ppp.phase = Establish;
2820 session[s].ppp.lcp = Starting;
2821
2822 STAT(session_created);
2823 break;
2824 }
2825
2826 {
2827 controlt *c = controlnew(14); // CDN
2828 if (!sessionfree)
2829 {
2830 STAT(session_overflow);
2831 LOG(1, 0, t, "No free sessions\n");
2832 control16(c, 1, 4, 0); // temporary lack of resources
2833 }
2834 else
2835 control16(c, 1, 2, 7); // shutting down, try another
2836
2837 controladd(c, asession, t); // send the message
2838 }
2839 return;
2840 case 11: // ICRP
2841 // TBA
2842 break;
2843 case 12: // ICCN
2844 if (amagic == 0) amagic = time_now;
2845 session[s].magic = amagic; // set magic number
2846 session[s].flags = aflags; // set flags received
2847 session[s].mru = PPPoE_MRU; // default
2848 controlnull(t); // ack
2849
2850 // start LCP
2851 sess_local[s].lcp_authtype = config->radius_authprefer;
2852 sess_local[s].ppp_mru = MRU;
2853
2854 // Set multilink options before sending initial LCP packet
2855 sess_local[s].mp_mrru = 1614;
2856 sess_local[s].mp_epdis = config->bind_address ? config->bind_address : my_address;
2857
2858 sendlcp(s, t);
2859 change_state(s, lcp, RequestSent);
2860 break;
2861
2862 case 14: // CDN
2863 controlnull(t); // ack
2864 sessionshutdown(s, disc_reason, CDN_NONE, disc_cause);
2865 break;
2866 case 0xFFFF:
2867 LOG(1, s, t, "Missing message type\n");
2868 break;
2869 default:
2870 STAT(tunnel_rx_errors);
2871 if (mandatory)
2872 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2873 else
2874 LOG(1, s, t, "Unknown message type %u\n", message);
2875 break;
2876 }
2877 if (chapresponse) free(chapresponse);
2878 cluster_send_tunnel(t);
2879 }
2880 else
2881 {
2882 LOG(4, s, t, " Got a ZLB ack\n");
2883 }
2884 }
2885 else
2886 { // data
2887 uint16_t proto;
2888
2889 LOG_HEX(5, "Receive Tunnel Data", p, l);
2890 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2891 { // HDLC address header, discard
2892 p += 2;
2893 l -= 2;
2894 }
2895 if (l < 2)
2896 {
2897 LOG(1, s, t, "Short ppp length %d\n", l);
2898 STAT(tunnel_rx_errors);
2899 return;
2900 }
2901 if (*p & 1)
2902 {
2903 proto = *p++;
2904 l--;
2905 }
2906 else
2907 {
2908 proto = ntohs(*(uint16_t *) p);
2909 p += 2;
2910 l -= 2;
2911 }
2912
2913 if (s && !session[s].opened) // Is something wrong??
2914 {
2915 if (!config->cluster_iam_master)
2916 {
2917 // Pass it off to the master to deal with..
2918 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2919 return;
2920 }
2921
2922
2923 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2924 STAT(tunnel_rx_errors);
2925 return;
2926 }
2927
2928 if (proto == PPPPAP)
2929 {
2930 session[s].last_packet = time_now;
2931 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2932 processpap(s, t, p, l);
2933 }
2934 else if (proto == PPPCHAP)
2935 {
2936 session[s].last_packet = time_now;
2937 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2938 processchap(s, t, p, l);
2939 }
2940 else if (proto == PPPLCP)
2941 {
2942 session[s].last_packet = time_now;
2943 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2944 processlcp(s, t, p, l);
2945 }
2946 else if (proto == PPPIPCP)
2947 {
2948 session[s].last_packet = time_now;
2949 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2950 processipcp(s, t, p, l);
2951 }
2952 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2953 {
2954 session[s].last_packet = time_now;
2955 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2956 processipv6cp(s, t, p, l);
2957 }
2958 else if (proto == PPPCCP)
2959 {
2960 session[s].last_packet = time_now;
2961 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2962 processccp(s, t, p, l);
2963 }
2964 else if (proto == PPPIP)
2965 {
2966 if (session[s].die)
2967 {
2968 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2969 return; // closing session, PPP not processed
2970 }
2971
2972 session[s].last_packet = session[s].last_data = time_now;
2973 if (session[s].walled_garden && !config->cluster_iam_master)
2974 {
2975 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2976 return;
2977 }
2978
2979 processipin(s, t, p, l);
2980 }
2981 else if (proto == PPPMP)
2982 {
2983 if (session[s].die)
2984 {
2985 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
2986 return; // closing session, PPP not processed
2987 }
2988
2989 session[s].last_packet = session[s].last_data = time_now;
2990 if (session[s].walled_garden && !config->cluster_iam_master)
2991 {
2992 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2993 return;
2994 }
2995
2996 processmpin(s, t, p, l);
2997 }
2998 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2999 {
3000 if (session[s].die)
3001 {
3002 LOG(4, s, t, "Session %u is closing. Don't process PPP packets\n", s);
3003 return; // closing session, PPP not processed
3004 }
3005
3006 session[s].last_packet = session[s].last_data = time_now;
3007 if (session[s].walled_garden && !config->cluster_iam_master)
3008 {
3009 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
3010 return;
3011 }
3012
3013 processipv6in(s, t, p, l);
3014 }
3015 else if (session[s].ppp.lcp == Opened)
3016 {
3017 session[s].last_packet = time_now;
3018 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
3019 protoreject(s, t, p, l, proto);
3020 }
3021 else
3022 {
3023 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
3024 proto, ppp_state(session[s].ppp.lcp));
3025 }
3026 }
3027 }
3028
3029 // read and process packet on tun
3030 static void processtun(uint8_t * buf, int len)
3031 {
3032 LOG_HEX(5, "Receive TUN Data", buf, len);
3033 STAT(tun_rx_packets);
3034 INC_STAT(tun_rx_bytes, len);
3035
3036 CSTAT(processtun);
3037
3038 eth_rx_pkt++;
3039 eth_rx += len;
3040 if (len < 22)
3041 {
3042 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
3043 STAT(tun_rx_errors);
3044 return;
3045 }
3046
3047 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
3048 processipout(buf, len);
3049 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
3050 && config->ipv6_prefix.s6_addr[0])
3051 processipv6out(buf, len);
3052
3053 // Else discard.
3054 }
3055
3056 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
3057 // that we look at the whole of the tunnel, radius and session tables
3058 // every second
3059 static void regular_cleanups(double period)
3060 {
3061 // Next tunnel, radius and session to check for actions on.
3062 static tunnelidt t = 0;
3063 static int r = 0;
3064 static sessionidt s = 0;
3065
3066 int t_actions = 0;
3067 int r_actions = 0;
3068 int s_actions = 0;
3069
3070 int t_slice;
3071 int r_slice;
3072 int s_slice;
3073
3074 int i;
3075 int a;
3076
3077 // divide up tables into slices based on the last run
3078 t_slice = config->cluster_highest_tunnelid * period;
3079 r_slice = (MAXRADIUS - 1) * period;
3080 s_slice = config->cluster_highest_sessionid * period;
3081
3082 if (t_slice < 1)
3083 t_slice = 1;
3084 else if (t_slice > config->cluster_highest_tunnelid)
3085 t_slice = config->cluster_highest_tunnelid;
3086
3087 if (r_slice < 1)
3088 r_slice = 1;
3089 else if (r_slice > (MAXRADIUS - 1))
3090 r_slice = MAXRADIUS - 1;
3091
3092 if (s_slice < 1)
3093 s_slice = 1;
3094 else if (s_slice > config->cluster_highest_sessionid)
3095 s_slice = config->cluster_highest_sessionid;
3096
3097 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
3098
3099 for (i = 0; i < t_slice; i++)
3100 {
3101 t++;
3102 if (t > config->cluster_highest_tunnelid)
3103 t = 1;
3104
3105 // check for expired tunnels
3106 if (tunnel[t].die && tunnel[t].die <= TIME)
3107 {
3108 STAT(tunnel_timeout);
3109 tunnelkill(t, "Expired");
3110 t_actions++;
3111 continue;
3112 }
3113 // check for message resend
3114 if (tunnel[t].retry && tunnel[t].controlc)
3115 {
3116 // resend pending messages as timeout on reply
3117 if (tunnel[t].retry <= TIME)
3118 {
3119 controlt *c = tunnel[t].controls;
3120 uint16_t w = tunnel[t].window;
3121 tunnel[t].try++; // another try
3122 if (tunnel[t].try > 5)
3123 tunnelkill(t, "Timeout on control message"); // game over
3124 else
3125 while (c && w--)
3126 {
3127 tunnelsend(c->buf, c->length, t);
3128 c = c->next;
3129 }
3130
3131 t_actions++;
3132 }
3133 }
3134 // Send hello
3135 if (tunnel[t].state == TUNNELOPEN && !tunnel[t].controlc && (time_now - tunnel[t].lastrec) > 60)
3136 {
3137 controlt *c = controlnew(6); // sending HELLO
3138 controladd(c, 0, t); // send the message
3139 LOG(3, 0, t, "Sending HELLO message\n");
3140 t_actions++;
3141 }
3142
3143 // Check for tunnel changes requested from the CLI
3144 if ((a = cli_tunnel_actions[t].action))
3145 {
3146 cli_tunnel_actions[t].action = 0;
3147 if (a & CLI_TUN_KILL)
3148 {
3149 LOG(2, 0, t, "Dropping tunnel by CLI\n");
3150 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
3151 t_actions++;
3152 }
3153 }
3154 }
3155
3156 for (i = 0; i < r_slice; i++)
3157 {
3158 r++;
3159 if (r >= MAXRADIUS)
3160 r = 1;
3161
3162 if (!radius[r].state)
3163 continue;
3164
3165 if (radius[r].retry <= TIME)
3166 {
3167 radiusretry(r);
3168 r_actions++;
3169 }
3170 }
3171
3172 for (i = 0; i < s_slice; i++)
3173 {
3174 s++;
3175 if (s > config->cluster_highest_sessionid)
3176 s = 1;
3177
3178 if (!session[s].opened) // Session isn't in use
3179 continue;
3180
3181 // check for expired sessions
3182 if (session[s].die)
3183 {
3184 if (session[s].die <= TIME)
3185 {
3186 sessionkill(s, "Expired");
3187 s_actions++;
3188 }
3189 continue;
3190 }
3191
3192 // PPP timeouts
3193 if (sess_local[s].lcp.restart <= time_now)
3194 {
3195 int next_state = session[s].ppp.lcp;
3196 switch (session[s].ppp.lcp)
3197 {
3198 case RequestSent:
3199 case AckReceived:
3200 next_state = RequestSent;
3201
3202 case AckSent:
3203 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
3204 {
3205 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
3206 sendlcp(s, session[s].tunnel);
3207 change_state(s, lcp, next_state);
3208 }
3209 else
3210 {
3211 sessionshutdown(s, "No response to LCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3212 STAT(session_timeout);
3213 }
3214
3215 s_actions++;
3216 }
3217
3218 if (session[s].die)
3219 continue;
3220 }
3221
3222 if (sess_local[s].ipcp.restart <= time_now)
3223 {
3224 int next_state = session[s].ppp.ipcp;
3225 switch (session[s].ppp.ipcp)
3226 {
3227 case RequestSent:
3228 case AckReceived:
3229 next_state = RequestSent;
3230
3231 case AckSent:
3232 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
3233 {
3234 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
3235 sendipcp(s, session[s].tunnel);
3236 change_state(s, ipcp, next_state);
3237 }
3238 else
3239 {
3240 sessionshutdown(s, "No response to IPCP ConfigReq.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3241 STAT(session_timeout);
3242 }
3243
3244 s_actions++;
3245 }
3246
3247 if (session[s].die)
3248 continue;
3249 }
3250
3251 if (sess_local[s].ipv6cp.restart <= time_now)
3252 {
3253 int next_state = session[s].ppp.ipv6cp;
3254 switch (session[s].ppp.ipv6cp)
3255 {
3256 case RequestSent:
3257 case AckReceived:
3258 next_state = RequestSent;
3259
3260 case AckSent:
3261 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
3262 {
3263 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
3264 sendipv6cp(s, session[s].tunnel);
3265 change_state(s, ipv6cp, next_state);
3266 }
3267 else
3268 {
3269 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
3270 change_state(s, ipv6cp, Stopped);
3271 }
3272
3273 s_actions++;
3274 }
3275 }
3276
3277 if (sess_local[s].ccp.restart <= time_now)
3278 {
3279 int next_state = session[s].ppp.ccp;
3280 switch (session[s].ppp.ccp)
3281 {
3282 case RequestSent:
3283 case AckReceived:
3284 next_state = RequestSent;
3285
3286 case AckSent:
3287 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
3288 {
3289 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
3290 sendccp(s, session[s].tunnel);
3291 change_state(s, ccp, next_state);
3292 }
3293 else
3294 {
3295 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
3296 change_state(s, ccp, Stopped);
3297 }
3298
3299 s_actions++;
3300 }
3301 }
3302
3303 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
3304 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
3305 {
3306 sessionshutdown(s, "No response to LCP ECHO requests.", CDN_ADMIN_DISC, TERM_LOST_SERVICE);
3307 STAT(session_timeout);
3308 s_actions++;
3309 continue;
3310 }
3311
3312 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
3313 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT) &&
3314 (time_now - sess_local[s].last_echo >= ECHO_TIMEOUT))
3315 {
3316 uint8_t b[MAXETHER];
3317
3318 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP, 1, 0, 0);
3319 if (!q) continue;
3320
3321 *q = EchoReq;
3322 *(uint8_t *)(q + 1) = (time_now % 255); // ID
3323 *(uint16_t *)(q + 2) = htons(8); // Length
3324 *(uint32_t *)(q + 4) = session[s].ppp.lcp == Opened ? htonl(session[s].magic) : 0; // Magic Number
3325
3326 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
3327 (int)(time_now - session[s].last_packet));
3328 tunnelsend(b, 24, session[s].tunnel); // send it
3329 sess_local[s].last_echo = time_now;
3330 s_actions++;
3331 }
3332
3333 // Drop sessions who have reached session_timeout seconds
3334 if (session[s].session_timeout)
3335 {
3336 bundleidt bid = session[s].bundle;
3337 if (bid)
3338 {
3339 if (time_now - bundle[bid].last_check >= 1)
3340 {
3341 bundle[bid].online_time += (time_now - bundle[bid].last_check) * bundle[bid].num_of_links;
3342 bundle[bid].last_check = time_now;
3343 if (bundle[bid].online_time >= session[s].session_timeout)
3344 {
3345 int ses;
3346 for (ses = bundle[bid].num_of_links - 1; ses >= 0; ses--)
3347 {
3348 sessionshutdown(bundle[bid].members[ses], "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3349 s_actions++;
3350 continue;
3351 }
3352 }
3353 }
3354 }
3355 else if (time_now - session[s].opened >= session[s].session_timeout)
3356 {
3357 sessionshutdown(s, "Session timeout", CDN_ADMIN_DISC, TERM_SESSION_TIMEOUT);
3358 s_actions++;
3359 continue;
3360 }
3361 }
3362
3363 // Drop sessions who have reached idle_timeout seconds
3364 if (session[s].last_data && session[s].idle_timeout && (time_now - session[s].last_data >= session[s].idle_timeout))
3365 {
3366 sessionshutdown(s, "Idle Timeout Reached", CDN_ADMIN_DISC, TERM_IDLE_TIMEOUT);
3367 STAT(session_timeout);
3368 s_actions++;
3369 continue;
3370 }
3371
3372 // Check for actions requested from the CLI
3373 if ((a = cli_session_actions[s].action))
3374 {
3375 int send = 0;
3376
3377 cli_session_actions[s].action = 0;
3378 if (a & CLI_SESS_KILL)
3379 {
3380 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
3381 sessionshutdown(s, "Requested by administrator.", CDN_ADMIN_DISC, TERM_ADMIN_RESET);
3382 a = 0; // dead, no need to check for other actions
3383 s_actions++;
3384 }
3385
3386 if (a & CLI_SESS_NOSNOOP)
3387 {
3388 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
3389 session[s].snoop_ip = 0;
3390 session[s].snoop_port = 0;
3391 s_actions++;
3392 send++;
3393 }
3394 else if (a & CLI_SESS_SNOOP)
3395 {
3396 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%u)\n",
3397 fmtaddr(cli_session_actions[s].snoop_ip, 0),
3398 cli_session_actions[s].snoop_port);
3399
3400 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
3401 session[s].snoop_port = cli_session_actions[s].snoop_port;
3402 s_actions++;
3403 send++;
3404 }
3405
3406 if (a & CLI_SESS_NOTHROTTLE)
3407 {
3408 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
3409 throttle_session(s, 0, 0);
3410 s_actions++;
3411 send++;
3412 }
3413 else if (a & CLI_SESS_THROTTLE)
3414 {
3415 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
3416 cli_session_actions[s].throttle_in,
3417 cli_session_actions[s].throttle_out);
3418
3419 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
3420 s_actions++;
3421 send++;
3422 }
3423
3424 if (a & CLI_SESS_NOFILTER)
3425 {
3426 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3427 filter_session(s, 0, 0);
3428 s_actions++;
3429 send++;
3430 }
3431 else if (a & CLI_SESS_FILTER)
3432 {
3433 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3434 cli_session_actions[s].filter_in,
3435 cli_session_actions[s].filter_out);
3436
3437 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3438 s_actions++;
3439 send++;
3440 }
3441
3442 if (send)
3443 cluster_send_session(s);
3444 }
3445
3446 // RADIUS interim accounting
3447 if (config->radius_accounting && config->radius_interim > 0
3448 && session[s].ip && !session[s].walled_garden
3449 && !sess_local[s].radius // RADIUS already in progress
3450 && time_now - sess_local[s].last_interim >= config->radius_interim
3451 && session[s].flags & SESSION_STARTED)
3452 {
3453 int rad = radiusnew(s);
3454 if (!rad)
3455 {
3456 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3457 STAT(radius_overflow);
3458 continue;
3459 }
3460
3461 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3462 session[s].user, session[s].unique_id);
3463
3464 radiussend(rad, RADIUSINTERIM);
3465 sess_local[s].last_interim = time_now;
3466 s_actions++;
3467 }
3468 }
3469
3470 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3471 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3472 }
3473
3474 //
3475 // Are we in the middle of a tunnel update, or radius
3476 // requests??
3477 //
3478 static int still_busy(void)
3479 {
3480 int i;
3481 static clockt last_talked = 0;
3482 static clockt start_busy_wait = 0;
3483
3484 if (!config->cluster_iam_master)
3485 {
3486 #ifdef BGP
3487 static time_t stopped_bgp = 0;
3488 if (bgp_configured)
3489 {
3490 if (!stopped_bgp)
3491 {
3492 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3493
3494 for (i = 0; i < BGP_NUM_PEERS; i++)
3495 if (bgp_peers[i].state == Established)
3496 bgp_stop(&bgp_peers[i]);
3497
3498 stopped_bgp = time_now;
3499
3500 // we don't want to become master
3501 cluster_send_ping(0);
3502
3503 return 1;
3504 }
3505
3506 if (time_now < (stopped_bgp + QUIT_DELAY))
3507 return 1;
3508 }
3509 #endif /* BGP */
3510
3511 return 0;
3512 }
3513
3514 if (main_quit == QUIT_SHUTDOWN)
3515 {
3516 static int dropped = 0;
3517 if (!dropped)
3518 {
3519 int i;
3520
3521 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3522 for (i = 1; i < MAXTUNNEL; i++)
3523 if (tunnel[i].ip || tunnel[i].state)
3524 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3525
3526 dropped = 1;
3527 }
3528 }
3529
3530 if (start_busy_wait == 0)
3531 start_busy_wait = TIME;
3532
3533 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3534 {
3535 if (!tunnel[i].controlc)
3536 continue;
3537
3538 if (last_talked != TIME)
3539 {
3540 LOG(2, 0, 0, "Tunnel %u still has un-acked control messages.\n", i);
3541 last_talked = TIME;
3542 }
3543 return 1;
3544 }
3545
3546 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3547 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3548 {
3549 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3550 return 0;
3551 }
3552
3553 for (i = 1; i < MAXRADIUS; i++)
3554 {
3555 if (radius[i].state == RADIUSNULL)
3556 continue;
3557 if (radius[i].state == RADIUSWAIT)
3558 continue;
3559
3560 if (last_talked != TIME)
3561 {
3562 LOG(2, 0, 0, "Radius session %u is still busy (sid %u)\n", i, radius[i].session);
3563 last_talked = TIME;
3564 }
3565 return 1;
3566 }
3567
3568 return 0;
3569 }
3570
3571 #ifdef HAVE_EPOLL
3572 # include <sys/epoll.h>
3573 #else
3574 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3575 # include "fake_epoll.h"
3576 #endif
3577
3578 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3579 #define BASE_FDS 6
3580
3581 // additional polled fds
3582 #ifdef BGP
3583 # define EXTRA_FDS BGP_NUM_PEERS
3584 #else
3585 # define EXTRA_FDS 0
3586 #endif
3587
3588 // main loop - gets packets on tun or udp and processes them
3589 static void mainloop(void)
3590 {
3591 int i;
3592 uint8_t buf[65536];
3593 clockt next_cluster_ping = 0; // send initial ping immediately
3594 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3595 int maxevent = sizeof(events)/sizeof(*events);
3596
3597 if ((epollfd = epoll_create(maxevent)) < 0)
3598 {
3599 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3600 exit(1);
3601 }
3602
3603 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3604 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3605
3606 /* setup our fds to poll for input */
3607 {
3608 static struct event_data d[BASE_FDS];
3609 struct epoll_event e;
3610
3611 e.events = EPOLLIN;
3612 i = 0;
3613
3614 if (clifd >= 0)
3615 {
3616 d[i].type = FD_TYPE_CLI;
3617 e.data.ptr = &d[i++];
3618 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3619 }
3620
3621 d[i].type = FD_TYPE_CLUSTER;
3622 e.data.ptr = &d[i++];
3623 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3624
3625 d[i].type = FD_TYPE_TUN;
3626 e.data.ptr = &d[i++];
3627 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3628
3629 d[i].type = FD_TYPE_UDP;
3630 e.data.ptr = &d[i++];
3631 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3632
3633 d[i].type = FD_TYPE_CONTROL;
3634 e.data.ptr = &d[i++];
3635 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3636
3637 d[i].type = FD_TYPE_DAE;
3638 e.data.ptr = &d[i++];
3639 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3640 }
3641
3642 #ifdef BGP
3643 signal(SIGPIPE, SIG_IGN);
3644 bgp_setup(config->as_number);
3645 if (config->bind_address)
3646 bgp_add_route(config->bind_address, 0xffffffff);
3647
3648 for (i = 0; i < BGP_NUM_PEERS; i++)
3649 {
3650 if (config->neighbour[i].name[0])
3651 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3652 config->neighbour[i].as, config->neighbour[i].keepalive,
3653 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3654 }
3655 #endif /* BGP */
3656
3657 while (!main_quit || still_busy())
3658 {
3659 int more = 0;
3660 int n;
3661
3662
3663 if (main_reload)
3664 {
3665 main_reload = 0;
3666 read_config_file();
3667 config->reload_config++;
3668 }
3669
3670 if (config->reload_config)
3671 {
3672 config->reload_config = 0;
3673 update_config();
3674 }
3675
3676 #ifdef BGP
3677 bgp_set_poll();
3678 #endif /* BGP */
3679
3680 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3681 STAT(select_called);
3682
3683 TIME = now(NULL);
3684 if (n < 0)
3685 {
3686 if (errno == EINTR ||
3687 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3688 continue;
3689
3690 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3691 break; // exit
3692 }
3693
3694 if (n)
3695 {
3696 struct sockaddr_in addr;
3697 struct in_addr local;
3698 socklen_t alen;
3699 int c, s;
3700 int udp_ready = 0;
3701 int tun_ready = 0;
3702 int cluster_ready = 0;
3703 int udp_pkts = 0;
3704 int tun_pkts = 0;
3705 int cluster_pkts = 0;
3706 #ifdef BGP
3707 uint32_t bgp_events[BGP_NUM_PEERS];
3708 memset(bgp_events, 0, sizeof(bgp_events));
3709 #endif /* BGP */
3710
3711 for (c = n, i = 0; i < c; i++)
3712 {
3713 struct event_data *d = events[i].data.ptr;
3714
3715 switch (d->type)
3716 {
3717 case FD_TYPE_CLI: // CLI connections
3718 {
3719 int cli;
3720
3721 alen = sizeof(addr);
3722 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3723 {
3724 cli_do(cli);
3725 close(cli);
3726 }
3727 else
3728 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3729
3730 n--;
3731 break;
3732 }
3733
3734 // these are handled below, with multiple interleaved reads
3735 case FD_TYPE_CLUSTER: cluster_ready++; break;
3736 case FD_TYPE_TUN: tun_ready++; break;
3737 case FD_TYPE_UDP: udp_ready++; break;
3738
3739 case FD_TYPE_CONTROL: // nsctl commands
3740 alen = sizeof(addr);
3741 s = recvfromto(controlfd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3742 if (s > 0) processcontrol(buf, s, &addr, alen, &local);
3743 n--;
3744 break;
3745
3746 case FD_TYPE_DAE: // DAE requests
3747 alen = sizeof(addr);
3748 s = recvfromto(daefd, buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen, &local);
3749 if (s > 0) processdae(buf, s, &addr, alen, &local);
3750 n--;
3751 break;
3752
3753 case FD_TYPE_RADIUS: // RADIUS response
3754 alen = sizeof(addr);
3755 s = recvfrom(radfds[d->index], buf, sizeof(buf), MSG_WAITALL, (struct sockaddr *) &addr, &alen);
3756 if (s >= 0 && config->cluster_iam_master)
3757 {
3758 if (addr.sin_addr.s_addr == config->radiusserver[0] ||
3759 addr.sin_addr.s_addr == config->radiusserver[1])
3760 processrad(buf, s, d->index);
3761 else
3762 LOG(3, 0, 0, "Dropping RADIUS packet from unknown source %s\n",
3763 fmtaddr(addr.sin_addr.s_addr, 0));
3764 }
3765
3766 n--;
3767 break;
3768
3769 #ifdef BGP
3770 case FD_TYPE_BGP:
3771 bgp_events[d->index] = events[i].events;
3772 n--;
3773 break;
3774 #endif /* BGP */
3775
3776 default:
3777 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3778 }
3779 }
3780
3781 #ifdef BGP
3782 bgp_process(bgp_events);
3783 #endif /* BGP */
3784
3785 for (c = 0; n && c < config->multi_read_count; c++)
3786 {
3787 // L2TP
3788 if (udp_ready)
3789 {
3790 alen = sizeof(addr);
3791 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3792 {
3793 processudp(buf, s, &addr);
3794 udp_pkts++;
3795 }
3796 else
3797 {
3798 udp_ready = 0;
3799 n--;
3800 }
3801 }
3802
3803 // incoming IP
3804 if (tun_ready)
3805 {
3806 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3807 {
3808 processtun(buf, s);
3809 tun_pkts++;
3810 }
3811 else
3812 {
3813 tun_ready = 0;
3814 n--;
3815 }
3816 }
3817
3818 // cluster
3819 if (cluster_ready)
3820 {
3821 alen = sizeof(addr);
3822 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3823 {
3824 processcluster(buf, s, addr.sin_addr.s_addr);
3825 cluster_pkts++;
3826 }
3827 else
3828 {
3829 cluster_ready = 0;
3830 n--;
3831 }
3832 }
3833 }
3834
3835 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3836 STAT(multi_read_used);
3837
3838 if (c >= config->multi_read_count)
3839 {
3840 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3841 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3842
3843 STAT(multi_read_exceeded);
3844 more++;
3845 }
3846 }
3847
3848 if (time_changed)
3849 {
3850 double Mbps = 1024.0 * 1024.0 / 8 * time_changed;
3851
3852 // Log current traffic stats
3853 snprintf(config->bandwidth, sizeof(config->bandwidth),
3854 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3855 (udp_rx / Mbps), (eth_tx / Mbps), (eth_rx / Mbps), (udp_tx / Mbps),
3856 ((udp_tx + udp_rx + eth_tx + eth_rx) / Mbps),
3857 udp_rx_pkt / time_changed, eth_rx_pkt / time_changed);
3858
3859 udp_tx = udp_rx = 0;
3860 udp_rx_pkt = eth_rx_pkt = 0;
3861 eth_tx = eth_rx = 0;
3862 time_changed = 0;
3863
3864 if (config->dump_speed)
3865 printf("%s\n", config->bandwidth);
3866
3867 // Update the internal time counter
3868 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3869
3870 {
3871 // Run timer hooks
3872 struct param_timer p = { time_now };
3873 run_plugins(PLUGIN_TIMER, &p);
3874 }
3875 }
3876
3877 // Runs on every machine (master and slaves).
3878 if (next_cluster_ping <= TIME)
3879 {
3880 // Check to see which of the cluster is still alive..
3881
3882 cluster_send_ping(basetime); // Only does anything if we're a slave
3883 cluster_check_master(); // ditto.
3884
3885 cluster_heartbeat(); // Only does anything if we're a master.
3886 cluster_check_slaves(); // ditto.
3887
3888 master_update_counts(); // If we're a slave, send our byte counters to our master.
3889
3890 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3891 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3892 else
3893 next_cluster_ping = TIME + config->cluster_hb_interval;
3894 }
3895
3896 if (!config->cluster_iam_master)
3897 continue;
3898
3899 // Run token bucket filtering queue..
3900 // Only run it every 1/10th of a second.
3901 {
3902 static clockt last_run = 0;
3903 if (last_run != TIME)
3904 {
3905 last_run = TIME;
3906 tbf_run_timer();
3907 }
3908 }
3909
3910 // Handle timeouts, retries etc.
3911 {
3912 static double last_clean = 0;
3913 double this_clean;
3914 double diff;
3915
3916 TIME = now(&this_clean);
3917 diff = this_clean - last_clean;
3918
3919 // Run during idle time (after we've handled
3920 // all incoming packets) or every 1/10th sec
3921 if (!more || diff > 0.1)
3922 {
3923 regular_cleanups(diff);
3924 last_clean = this_clean;
3925 }
3926 }
3927
3928 if (*config->accounting_dir)
3929 {
3930 static clockt next_acct = 0;
3931 static clockt next_shut_acct = 0;
3932
3933 if (next_acct <= TIME)
3934 {
3935 // Dump accounting data
3936 next_acct = TIME + ACCT_TIME;
3937 next_shut_acct = TIME + ACCT_SHUT_TIME;
3938 dump_acct_info(1);
3939 }
3940 else if (next_shut_acct <= TIME)
3941 {
3942 // Dump accounting data for shutdown sessions
3943 next_shut_acct = TIME + ACCT_SHUT_TIME;
3944 if (shut_acct_n)
3945 dump_acct_info(0);
3946 }
3947 }
3948 }
3949
3950 // Are we the master and shutting down??
3951 if (config->cluster_iam_master)
3952 cluster_heartbeat(); // Flush any queued changes..
3953
3954 // Ok. Notify everyone we're shutting down. If we're
3955 // the master, this will force an election.
3956 cluster_send_ping(0);
3957
3958 //
3959 // Important!!! We MUST not process any packets past this point!
3960 LOG(1, 0, 0, "Shutdown complete\n");
3961 }
3962
3963 static void stripdomain(char *host)
3964 {
3965 char *p;
3966
3967 if ((p = strchr(host, '.')))
3968 {
3969 char *domain = 0;
3970 char _domain[1024];
3971
3972 // strip off domain
3973 FILE *resolv = fopen("/etc/resolv.conf", "r");
3974 if (resolv)
3975 {
3976 char buf[1024];
3977 char *b;
3978
3979 while (fgets(buf, sizeof(buf), resolv))
3980 {
3981 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3982 continue;
3983
3984 if (!isspace(buf[6]))
3985 continue;
3986
3987 b = buf + 7;
3988 while (isspace(*b)) b++;
3989
3990 if (*b)
3991 {
3992 char *d = b;
3993 while (*b && !isspace(*b)) b++;
3994 *b = 0;
3995 if (buf[0] == 'd') // domain is canonical
3996 {
3997 domain = d;
3998 break;
3999 }
4000
4001 // first search line
4002 if (!domain)
4003 {
4004 // hold, may be subsequent domain line
4005 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
4006 domain = _domain;
4007 }
4008 }
4009 }
4010
4011 fclose(resolv);
4012 }
4013
4014 if (domain)
4015 {
4016 int hl = strlen(host);
4017 int dl = strlen(domain);
4018 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
4019 host[hl -dl - 1] = 0;
4020 }
4021 else
4022 {
4023 *p = 0; // everything after first dot
4024 }
4025 }
4026 }
4027
4028 // Init data structures
4029 static void initdata(int optdebug, char *optconfig)
4030 {
4031 int i;
4032
4033 if (!(config = shared_malloc(sizeof(configt))))
4034 {
4035 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
4036 exit(1);
4037 }
4038
4039 memset(config, 0, sizeof(configt));
4040 time(&config->start_time);
4041 strncpy(config->config_file, optconfig, strlen(optconfig));
4042 config->debug = optdebug;
4043 config->num_tbfs = MAXTBFS;
4044 config->rl_rate = 28; // 28kbps
4045 config->cluster_mcast_ttl = 1;
4046 config->cluster_master_min_adv = 1;
4047 config->ppp_restart_time = 3;
4048 config->ppp_max_configure = 10;
4049 config->ppp_max_failure = 5;
4050 config->kill_timedout_sessions = 1;
4051 strcpy(config->random_device, RANDOMDEVICE);
4052
4053 log_stream = stderr;
4054
4055 #ifdef RINGBUFFER
4056 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
4057 {
4058 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
4059 exit(1);
4060 }
4061 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
4062 #endif
4063
4064 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
4065 {
4066 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
4067 exit(1);
4068 }
4069 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
4070 {
4071 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
4072 exit(1);
4073 }
4074 if (!(bundle = shared_malloc(sizeof(bundlet) * MAXBUNDLE)))
4075 {
4076 LOG(0, 0, 0, "Error doing malloc for bundles: %s\n", strerror(errno));
4077 exit(1);
4078 }
4079 if (!(frag = shared_malloc(sizeof(fragmentationt) * MAXBUNDLE)))
4080 {
4081 LOG(0, 0, 0, "Error doing malloc for fragmentations: %s\n", strerror(errno));
4082 exit(1);
4083 }
4084 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
4085 {
4086 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
4087 exit(1);
4088 }
4089
4090 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
4091 {
4092 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
4093 exit(1);
4094 }
4095
4096 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
4097 {
4098 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
4099 exit(1);
4100 }
4101
4102 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
4103 {
4104 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
4105 exit(1);
4106 }
4107
4108 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
4109 {
4110 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
4111 exit(1);
4112 }
4113 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
4114
4115 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
4116 {
4117 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
4118 exit(1);
4119 }
4120 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
4121
4122 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
4123 {
4124 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
4125 exit(1);
4126 }
4127 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
4128
4129 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
4130 memset(bundle, 0, sizeof(bundlet) * MAXBUNDLE);
4131 memset(session, 0, sizeof(sessiont) * MAXSESSION);
4132 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
4133 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
4134
4135 // Put all the sessions on the free list marked as undefined.
4136 for (i = 1; i < MAXSESSION; i++)
4137 {
4138 session[i].next = i + 1;
4139 session[i].tunnel = T_UNDEF; // mark it as not filled in.
4140 }
4141 session[MAXSESSION - 1].next = 0;
4142 sessionfree = 1;
4143
4144 // Mark all the tunnels as undefined (waiting to be filled in by a download).
4145 for (i = 1; i < MAXTUNNEL; i++)
4146 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
4147
4148 for (i = 1; i < MAXBUNDLE; i++) {
4149 bundle[i].state = BUNDLEUNDEF;
4150 }
4151
4152 if (!*hostname)
4153 {
4154 // Grab my hostname unless it's been specified
4155 gethostname(hostname, sizeof(hostname));
4156 stripdomain(hostname);
4157 }
4158
4159 _statistics->start_time = _statistics->last_reset = time(NULL);
4160
4161 #ifdef BGP
4162 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
4163 {
4164 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
4165 exit(1);
4166 }
4167 #endif /* BGP */
4168 }
4169
4170 static int assign_ip_address(sessionidt s)
4171 {
4172 uint32_t i;
4173 int best = -1;
4174 time_t best_time = time_now;
4175 char *u = session[s].user;
4176 char reuse = 0;
4177
4178
4179 CSTAT(assign_ip_address);
4180
4181 for (i = 1; i < ip_pool_size; i++)
4182 {
4183 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
4184 continue;
4185
4186 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
4187 {
4188 best = i;
4189 reuse = 1;
4190 break;
4191 }
4192
4193 if (ip_address_pool[i].last < best_time)
4194 {
4195 best = i;
4196 if (!(best_time = ip_address_pool[i].last))
4197 break; // never used, grab this one
4198 }
4199 }
4200
4201 if (best < 0)
4202 {
4203 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
4204 return 0;
4205 }
4206
4207 session[s].ip = ip_address_pool[best].address;
4208 session[s].ip_pool_index = best;
4209 ip_address_pool[best].assigned = 1;
4210 ip_address_pool[best].last = time_now;
4211 ip_address_pool[best].session = s;
4212 if (session[s].walled_garden)
4213 /* Don't track addresses of users in walled garden (note: this
4214 means that their address isn't "sticky" even if they get
4215 un-gardened). */
4216 ip_address_pool[best].user[0] = 0;
4217 else
4218 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
4219
4220 STAT(ip_allocated);
4221 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
4222 reuse ? "Reusing" : "Allocating", best);
4223
4224 return 1;
4225 }
4226
4227 static void free_ip_address(sessionidt s)
4228 {
4229 int i = session[s].ip_pool_index;
4230
4231
4232 CSTAT(free_ip_address);
4233
4234 if (!session[s].ip)
4235 return; // what the?
4236
4237 if (i < 0) // Is this actually part of the ip pool?
4238 i = 0;
4239
4240 STAT(ip_freed);
4241 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
4242 session[s].ip = 0;
4243 ip_address_pool[i].assigned = 0;
4244 ip_address_pool[i].session = 0;
4245 ip_address_pool[i].last = time_now;
4246 }
4247
4248 //
4249 // Fsck the address pool against the session table.
4250 // Normally only called when we become a master.
4251 //
4252 // This isn't perfect: We aren't keep tracking of which
4253 // users used to have an IP address.
4254 //
4255 void rebuild_address_pool(void)
4256 {
4257 int i;
4258
4259 //
4260 // Zero the IP pool allocation, and build
4261 // a map from IP address to pool index.
4262 for (i = 1; i < MAXIPPOOL; ++i)
4263 {
4264 ip_address_pool[i].assigned = 0;
4265 ip_address_pool[i].session = 0;
4266 if (!ip_address_pool[i].address)
4267 continue;
4268
4269 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
4270 }
4271
4272 for (i = 0; i < MAXSESSION; ++i)
4273 {
4274 int ipid;
4275 if (!(session[i].opened && session[i].ip))
4276 continue;
4277
4278 ipid = - lookup_ipmap(htonl(session[i].ip));
4279
4280 if (session[i].ip_pool_index < 0)
4281 {
4282 // Not allocated out of the pool.
4283 if (ipid < 1) // Not found in the pool either? good.
4284 continue;
4285
4286 LOG(0, i, 0, "Session %u has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
4287 i, fmtaddr(session[i].ip, 0), ipid);
4288
4289 // Fall through and process it as part of the pool.
4290 }
4291
4292
4293 if (ipid > MAXIPPOOL || ipid < 0)
4294 {
4295 LOG(0, i, 0, "Session %u has a pool IP that's not found in the pool! (%d)\n", i, ipid);
4296 ipid = -1;
4297 session[i].ip_pool_index = ipid;
4298 continue;
4299 }
4300
4301 ip_address_pool[ipid].assigned = 1;
4302 ip_address_pool[ipid].session = i;
4303 ip_address_pool[ipid].last = time_now;
4304 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
4305 session[i].ip_pool_index = ipid;
4306 cache_ipmap(session[i].ip, i); // Fix the ip map.
4307 }
4308 }
4309
4310 //
4311 // Fix the address pool to match a changed session.
4312 // (usually when the master sends us an update).
4313 static void fix_address_pool(int sid)
4314 {
4315 int ipid;
4316
4317 ipid = session[sid].ip_pool_index;
4318
4319 if (ipid > ip_pool_size)
4320 return; // Ignore it. rebuild_address_pool will fix it up.
4321
4322 if (ip_address_pool[ipid].address != session[sid].ip)
4323 return; // Just ignore it. rebuild_address_pool will take care of it.
4324
4325 ip_address_pool[ipid].assigned = 1;
4326 ip_address_pool[ipid].session = sid;
4327 ip_address_pool[ipid].last = time_now;
4328 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
4329 }
4330
4331 //
4332 // Add a block of addresses to the IP pool to hand out.
4333 //
4334 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
4335 {
4336 int i;
4337 if (mask == 0)
4338 mask = 0xffffffff; // Host route only.
4339
4340 addr &= mask;
4341
4342 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
4343 return ;
4344
4345 for (i = addr ;(i & mask) == addr; ++i)
4346 {
4347 if ((i & 0xff) == 0 || (i&0xff) == 255)
4348 continue; // Skip 0 and broadcast addresses.
4349
4350 ip_address_pool[ip_pool_size].address = i;
4351 ip_address_pool[ip_pool_size].assigned = 0;
4352 ++ip_pool_size;
4353 if (ip_pool_size >= MAXIPPOOL)
4354 {
4355 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
4356 return;
4357 }
4358 }
4359 }
4360
4361 // Initialize the IP address pool
4362 static void initippool()
4363 {
4364 FILE *f;
4365 char *p;
4366 char buf[4096];
4367 memset(ip_address_pool, 0, sizeof(ip_address_pool));
4368
4369 if (!(f = fopen(IPPOOLFILE, "r")))
4370 {
4371 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
4372 exit(1);
4373 }
4374
4375 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
4376 {
4377 char *pool = buf;
4378 buf[4095] = 0; // Force it to be zero terminated/
4379
4380 if (*buf == '#' || *buf == '\n')
4381 continue; // Skip comments / blank lines
4382 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
4383 if ((p = (char *)strchr(buf, ':')))
4384 {
4385 in_addr_t src;
4386 *p = '\0';
4387 src = inet_addr(buf);
4388 if (src == INADDR_NONE)
4389 {
4390 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
4391 exit(1);
4392 }
4393 // This entry is for a specific IP only
4394 if (src != config->bind_address)
4395 continue;
4396 *p = ':';
4397 pool = p+1;
4398 }
4399 if ((p = (char *)strchr(pool, '/')))
4400 {
4401 // It's a range
4402 int numbits = 0;
4403 in_addr_t start = 0, mask = 0;
4404
4405 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
4406 *p++ = 0;
4407 if (!*p || !(numbits = atoi(p)))
4408 {
4409 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
4410 continue;
4411 }
4412 start = ntohl(inet_addr(pool));
4413 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
4414
4415 // Add a static route for this pool
4416 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
4417 fmtaddr(htonl(start), 0), 32 + mask);
4418
4419 routeset(0, start, mask, 0, 1);
4420
4421 add_to_ip_pool(start, mask);
4422 }
4423 else
4424 {
4425 // It's a single ip address
4426 add_to_ip_pool(ntohl(inet_addr(pool)), 0);
4427 }
4428 }
4429 fclose(f);
4430 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
4431 }
4432
4433 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
4434 {
4435 struct sockaddr_in snoop_addr = {0};
4436 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
4437 return;
4438
4439 snoop_addr.sin_family = AF_INET;
4440 snoop_addr.sin_addr.s_addr = destination;
4441 snoop_addr.sin_port = ntohs(port);
4442
4443 LOG(5, 0, 0, "Snooping %d byte packet to %s:%u\n", size,
4444 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
4445 htons(snoop_addr.sin_port));
4446
4447 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
4448 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
4449
4450 STAT(packets_snooped);
4451 }
4452
4453 static int dump_session(FILE **f, sessiont *s)
4454 {
4455 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
4456 return 1;
4457
4458 if (!*f)
4459 {
4460 char filename[1024];
4461 char timestr[64];
4462 time_t now = time(NULL);
4463
4464 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
4465 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
4466
4467 if (!(*f = fopen(filename, "w")))
4468 {
4469 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
4470 return 0;
4471 }
4472
4473 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
4474 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
4475 "# host: %s\n"
4476 "# endpoint: %s\n"
4477 "# time: %ld\n"
4478 "# uptime: %ld\n"
4479 "# format: username ip qos uptxoctets downrxoctets\n",
4480 hostname,
4481 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
4482 now,
4483 now - basetime);
4484 }
4485
4486 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
4487 fprintf(*f, "%s %s %d %u %u\n",
4488 s->user, // username
4489 fmtaddr(htonl(s->ip), 0), // ip
4490 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
4491 (uint32_t) s->cin_delta, // uptxoctets
4492 (uint32_t) s->cout_delta); // downrxoctets
4493
4494 s->cin_delta = s->cout_delta = 0;
4495
4496 return 1;
4497 }
4498
4499 static void dump_acct_info(int all)
4500 {
4501 int i;
4502 FILE *f = NULL;
4503
4504
4505 CSTAT(dump_acct_info);
4506
4507 if (shut_acct_n)
4508 {
4509 for (i = 0; i < shut_acct_n; i++)
4510 dump_session(&f, &shut_acct[i]);
4511
4512 shut_acct_n = 0;
4513 }
4514
4515 if (all)
4516 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4517 dump_session(&f, &session[i]);
4518
4519 if (f)
4520 fclose(f);
4521 }
4522
4523 // Main program
4524 int main(int argc, char *argv[])
4525 {
4526 int i;
4527 int optdebug = 0;
4528 char *optconfig = CONFIGFILE;
4529
4530 time(&basetime); // start clock
4531
4532 // scan args
4533 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4534 {
4535 switch (i)
4536 {
4537 case 'd':
4538 if (fork()) exit(0);
4539 setsid();
4540 freopen("/dev/null", "r", stdin);
4541 freopen("/dev/null", "w", stdout);
4542 freopen("/dev/null", "w", stderr);
4543 break;
4544 case 'v':
4545 optdebug++;
4546 break;
4547 case 'c':
4548 optconfig = optarg;
4549 break;
4550 case 'h':
4551 snprintf(hostname, sizeof(hostname), "%s", optarg);
4552 break;
4553 default:
4554 printf("Args are:\n"
4555 "\t-d\t\tDetach from terminal\n"
4556 "\t-c <file>\tConfig file\n"
4557 "\t-h <hostname>\tForce hostname\n"
4558 "\t-v\t\tDebug\n");
4559
4560 return (0);
4561 break;
4562 }
4563 }
4564
4565 // Start the timer routine off
4566 time(&time_now);
4567 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4568
4569 initplugins();
4570 initdata(optdebug, optconfig);
4571
4572 init_cli(hostname);
4573 read_config_file();
4574 update_config();
4575 init_tbf(config->num_tbfs);
4576
4577 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4578 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005, 2006 Optus Internet Engineering\n");
4579 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4580 {
4581 struct rlimit rlim;
4582 rlim.rlim_cur = RLIM_INFINITY;
4583 rlim.rlim_max = RLIM_INFINITY;
4584 // Remove the maximum core size
4585 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4586 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4587
4588 // Make core dumps go to /tmp
4589 chdir("/tmp");
4590 }
4591
4592 if (config->scheduler_fifo)
4593 {
4594 int ret;
4595 struct sched_param params = {0};
4596 params.sched_priority = 1;
4597
4598 if (get_nprocs() < 2)
4599 {
4600 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4601 config->scheduler_fifo = 0;
4602 }
4603 else
4604 {
4605 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4606 {
4607 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4608 }
4609 else
4610 {
4611 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4612 config->scheduler_fifo = 0;
4613 }
4614 }
4615 }
4616
4617 /* Set up the cluster communications port. */
4618 if (cluster_init() < 0)
4619 exit(1);
4620
4621 inittun();
4622 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4623
4624 initudp();
4625 initrad();
4626 initippool();
4627
4628 // seed prng
4629 {
4630 unsigned seed = time_now ^ getpid();
4631 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4632 srand(seed);
4633 }
4634
4635 signal(SIGHUP, sighup_handler);
4636 signal(SIGCHLD, sigchild_handler);
4637 signal(SIGTERM, shutdown_handler);
4638 signal(SIGINT, shutdown_handler);
4639 signal(SIGQUIT, shutdown_handler);
4640
4641 // Prevent us from getting paged out
4642 if (config->lock_pages)
4643 {
4644 if (!mlockall(MCL_CURRENT))
4645 LOG(1, 0, 0, "Locking pages into memory\n");
4646 else
4647 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4648 }
4649
4650 mainloop();
4651
4652 /* remove plugins (so cleanup code gets run) */
4653 plugins_done();
4654
4655 // Remove the PID file if we wrote it
4656 if (config->wrote_pid && *config->pid_file == '/')
4657 unlink(config->pid_file);
4658
4659 /* kill CLI children */
4660 signal(SIGTERM, SIG_IGN);
4661 kill(0, SIGTERM);
4662 return 0;
4663 }
4664
4665 static void sighup_handler(int sig)
4666 {
4667 main_reload++;
4668 }
4669
4670 static void shutdown_handler(int sig)
4671 {
4672 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4673 }
4674
4675 static void sigchild_handler(int sig)
4676 {
4677 while (waitpid(-1, NULL, WNOHANG) > 0)
4678 ;
4679 }
4680
4681 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4682 {
4683 MD5_CTX ctx;
4684 *challenge_response = NULL;
4685
4686 if (!*config->l2tp_secret)
4687 {
4688 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4689 return;
4690 }
4691
4692 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4693
4694 *challenge_response = calloc(17, 1);
4695
4696 MD5_Init(&ctx);
4697 MD5_Update(&ctx, &id, 1);
4698 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4699 MD5_Update(&ctx, challenge, challenge_length);
4700 MD5_Final(*challenge_response, &ctx);
4701
4702 return;
4703 }
4704
4705 static int facility_value(char *name)
4706 {
4707 int i;
4708 for (i = 0; facilitynames[i].c_name; i++)
4709 {
4710 if (strcmp(facilitynames[i].c_name, name) == 0)
4711 return facilitynames[i].c_val;
4712 }
4713 return 0;
4714 }
4715
4716 static void update_config()
4717 {
4718 int i;
4719 char *p;
4720 static int timeout = 0;
4721 static int interval = 0;
4722
4723 // Update logging
4724 closelog();
4725 syslog_log = 0;
4726 if (log_stream)
4727 {
4728 if (log_stream != stderr)
4729 fclose(log_stream);
4730
4731 log_stream = NULL;
4732 }
4733
4734 if (*config->log_filename)
4735 {
4736 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4737 {
4738 char *p = config->log_filename + 7;
4739 if (*p)
4740 {
4741 openlog("l2tpns", LOG_PID, facility_value(p));
4742 syslog_log = 1;
4743 }
4744 }
4745 else if (strchr(config->log_filename, '/') == config->log_filename)
4746 {
4747 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4748 {
4749 fseek(log_stream, 0, SEEK_END);
4750 setbuf(log_stream, NULL);
4751 }
4752 else
4753 {
4754 log_stream = stderr;
4755 setbuf(log_stream, NULL);
4756 }
4757 }
4758 }
4759 else
4760 {
4761 log_stream = stderr;
4762 setbuf(log_stream, NULL);
4763 }
4764
4765 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4766 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4767
4768 if (config->l2tp_mtu <= 0) config->l2tp_mtu = 1500; // ethernet default
4769 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4770 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4771
4772 // reset MRU/MSS globals
4773 MRU = config->l2tp_mtu - L2TP_HDRS;
4774 if (MRU > PPPoE_MRU)
4775 MRU = PPPoE_MRU;
4776
4777 MSS = MRU - TCP_HDRS;
4778
4779 // Update radius
4780 config->numradiusservers = 0;
4781 for (i = 0; i < MAXRADSERVER; i++)
4782 if (config->radiusserver[i])
4783 {
4784 config->numradiusservers++;
4785 // Set radius port: if not set, take the port from the
4786 // first radius server. For the first radius server,
4787 // take the #defined default value from l2tpns.h
4788
4789 // test twice, In case someone works with
4790 // a secondary radius server without defining
4791 // a primary one, this will work even then.
4792 if (i > 0 && !config->radiusport[i])
4793 config->radiusport[i] = config->radiusport[i-1];
4794 if (!config->radiusport[i])
4795 config->radiusport[i] = RADPORT;
4796 }
4797
4798 if (!config->numradiusservers)
4799 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4800
4801 // parse radius_authtypes_s
4802 config->radius_authtypes = config->radius_authprefer = 0;
4803 p = config->radius_authtypes_s;
4804 while (p && *p)
4805 {
4806 char *s = strpbrk(p, " \t,");
4807 int type = 0;
4808
4809 if (s)
4810 {
4811 *s++ = 0;
4812 while (*s == ' ' || *s == '\t')
4813 s++;
4814
4815 if (!*s)
4816 s = 0;
4817 }
4818
4819 if (!strncasecmp("chap", p, strlen(p)))
4820 type = AUTHCHAP;
4821 else if (!strncasecmp("pap", p, strlen(p)))
4822 type = AUTHPAP;
4823 else
4824 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4825
4826 config->radius_authtypes |= type;
4827 if (!config->radius_authprefer)
4828 config->radius_authprefer = type;
4829
4830 p = s;
4831 }
4832
4833 if (!config->radius_authtypes)
4834 {
4835 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4836 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4837 }
4838
4839 // normalise radius_authtypes_s
4840 if (config->radius_authprefer == AUTHPAP)
4841 {
4842 strcpy(config->radius_authtypes_s, "pap");
4843 if (config->radius_authtypes & AUTHCHAP)
4844 strcat(config->radius_authtypes_s, ", chap");
4845 }
4846 else
4847 {
4848 strcpy(config->radius_authtypes_s, "chap");
4849 if (config->radius_authtypes & AUTHPAP)
4850 strcat(config->radius_authtypes_s, ", pap");
4851 }
4852
4853 if (!config->radius_dae_port)
4854 config->radius_dae_port = DAEPORT;
4855
4856 // re-initialise the random number source
4857 initrandom(config->random_device);
4858
4859 // Update plugins
4860 for (i = 0; i < MAXPLUGINS; i++)
4861 {
4862 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4863 continue;
4864
4865 if (*config->plugins[i])
4866 {
4867 // Plugin added
4868 add_plugin(config->plugins[i]);
4869 }
4870 else if (*config->old_plugins[i])
4871 {
4872 // Plugin removed
4873 remove_plugin(config->old_plugins[i]);
4874 }
4875 }
4876
4877 // Guest change
4878 guest_accounts_num = 0;
4879 char *p2 = config->guest_user;
4880 while (p2 && *p2)
4881 {
4882 char *s = strpbrk(p2, " \t,");
4883 if (s)
4884 {
4885 *s++ = 0;
4886 while (*s == ' ' || *s == '\t')
4887 s++;
4888
4889 if (!*s)
4890 s = 0;
4891 }
4892
4893 strcpy(guest_users[guest_accounts_num], p2);
4894 LOG(1, 0, 0, "Guest account[%d]: %s\n", guest_accounts_num, guest_users[guest_accounts_num]);
4895 guest_accounts_num++;
4896 p2 = s;
4897 }
4898 // Rebuild the guest_user array
4899 strcpy(config->guest_user, "");
4900 int ui = 0;
4901 for (ui=0; ui<guest_accounts_num; ui++)
4902 {
4903 strcat(config->guest_user, guest_users[ui]);
4904 if (ui<guest_accounts_num-1)
4905 {
4906 strcat(config->guest_user, ",");
4907 }
4908 }
4909
4910
4911 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4912 if (!config->multi_read_count) config->multi_read_count = 10;
4913 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4914 if (!*config->cluster_interface)
4915 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4916
4917 if (!config->cluster_hb_interval)
4918 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4919
4920 if (!config->cluster_hb_timeout)
4921 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4922
4923 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4924 {
4925 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4926 // late, ensure we're sufficiently larger than that
4927 int t = 4 * config->cluster_hb_interval + 11;
4928
4929 if (config->cluster_hb_timeout < t)
4930 {
4931 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4932 config->cluster_hb_timeout = t;
4933 }
4934
4935 // Push timing changes to the slaves immediately if we're the master
4936 if (config->cluster_iam_master)
4937 cluster_heartbeat();
4938
4939 interval = config->cluster_hb_interval;
4940 timeout = config->cluster_hb_timeout;
4941 }
4942
4943 // Write PID file
4944 if (*config->pid_file == '/' && !config->wrote_pid)
4945 {
4946 FILE *f;
4947 if ((f = fopen(config->pid_file, "w")))
4948 {
4949 fprintf(f, "%d\n", getpid());
4950 fclose(f);
4951 config->wrote_pid = 1;
4952 }
4953 else
4954 {
4955 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4956 }
4957 }
4958 }
4959
4960 static void read_config_file()
4961 {
4962 FILE *f;
4963
4964 if (!config->config_file) return;
4965 if (!(f = fopen(config->config_file, "r")))
4966 {
4967 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4968 return;
4969 }
4970
4971 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4972 cli_do_file(f);
4973 LOG(3, 0, 0, "Done reading config file\n");
4974 fclose(f);
4975 }
4976
4977 int sessionsetup(sessionidt s, tunnelidt t)
4978 {
4979 // A session now exists, set it up
4980 in_addr_t ip;
4981 char *user;
4982 sessionidt i;
4983 int r;
4984
4985 CSTAT(sessionsetup);
4986
4987 LOG(3, s, t, "Doing session setup for session\n");
4988
4989 // Join a bundle if the MRRU option is accepted
4990 if(session[s].mrru > 0 && session[s].bundle == 0)
4991 {
4992 LOG(3, s, t, "This session can be part of multilink bundle\n");
4993 if (join_bundle(s) > 0)
4994 cluster_send_bundle(session[s].bundle);
4995 else
4996 {
4997 LOG(0, s, t, "MPPP: Mismaching mssf option with other sessions in bundle\n");
4998 sessionshutdown(s, "Mismaching mssf option.", CDN_NONE, TERM_SERVICE_UNAVAILABLE);
4999 return 0;
5000 }
5001 }
5002
5003 if (!session[s].ip)
5004 {
5005 assign_ip_address(s);
5006 if (!session[s].ip)
5007 {
5008 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
5009 sessionshutdown(s, "No IP addresses available.", CDN_TRY_ANOTHER, TERM_SERVICE_UNAVAILABLE);
5010 return 0;
5011 }
5012 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
5013 fmtaddr(htonl(session[s].ip), 0));
5014 }
5015
5016
5017 // Make sure this is right
5018 session[s].tunnel = t;
5019
5020 // zap old sessions with same IP and/or username
5021 // Don't kill gardened sessions - doing so leads to a DoS
5022 // from someone who doesn't need to know the password
5023 {
5024 ip = session[s].ip;
5025 user = session[s].user;
5026 for (i = 1; i <= config->cluster_highest_sessionid; i++)
5027 {
5028 if (i == s) continue;
5029 if (!session[s].opened) continue;
5030 // Allow duplicate sessions for multilink ones of the same bundle.
5031 if (session[s].bundle && session[i].bundle && session[s].bundle == session[i].bundle)
5032 continue;
5033 if (ip == session[i].ip)
5034 {
5035 sessionkill(i, "Duplicate IP address");
5036 continue;
5037 }
5038
5039 if (config->allow_duplicate_users) continue;
5040 if (session[s].walled_garden || session[i].walled_garden) continue;
5041 // Guest change
5042 int found = 0;
5043 int gu;
5044 for (gu = 0; gu < guest_accounts_num; gu++)
5045 {
5046 if (!strcasecmp(user, guest_users[gu]))
5047 {
5048 found = 1;
5049 break;
5050 }
5051 }
5052 if (found) continue;
5053
5054 // Drop the new session in case of duplicate sessionss, not the old one.
5055 if (!strcasecmp(user, session[i].user))
5056 sessionkill(i, "Duplicate session for users");
5057 }
5058 }
5059
5060 // no need to set a route for the same IP address of the bundle
5061 if (!session[s].bundle || (bundle[session[s].bundle].num_of_links == 1))
5062 {
5063 int routed = 0;
5064
5065 // Add the route for this session.
5066 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
5067 {
5068 if ((session[s].ip & session[s].route[r].mask) ==
5069 (session[s].route[r].ip & session[s].route[r].mask))
5070 routed++;
5071
5072 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
5073 }
5074
5075 // Static IPs need to be routed if not already
5076 // convered by a Framed-Route. Anything else is part
5077 // of the IP address pool and is already routed, it
5078 // just needs to be added to the IP cache.
5079 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
5080 if (session[s].ip_pool_index == -1) // static ip
5081 {
5082 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
5083 }
5084 else
5085 cache_ipmap(session[s].ip, s);
5086 }
5087
5088 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
5089 lcp_open(s, t); // transition to Network phase and send initial IPCP
5090
5091 // Run the plugin's against this new session.
5092 {
5093 struct param_new_session data = { &tunnel[t], &session[s] };
5094 run_plugins(PLUGIN_NEW_SESSION, &data);
5095 }
5096
5097 // Allocate TBFs if throttled
5098 if (session[s].throttle_in || session[s].throttle_out)
5099 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
5100
5101 session[s].last_packet = session[s].last_data = time_now;
5102
5103 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
5104 fmtaddr(htonl(session[s].ip), 0),
5105 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
5106
5107 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
5108
5109 return 1; // RADIUS OK and IP allocated, done...
5110 }
5111
5112 //
5113 // This session just got dropped on us by the master or something.
5114 // Make sure our tables up up to date...
5115 //
5116 int load_session(sessionidt s, sessiont *new)
5117 {
5118 int i;
5119 int newip = 0;
5120
5121 // Sanity checks.
5122 if (new->ip_pool_index >= MAXIPPOOL ||
5123 new->tunnel >= MAXTUNNEL)
5124 {
5125 LOG(0, s, 0, "Strange session update received!\n");
5126 // FIXME! What to do here?
5127 return 0;
5128 }
5129
5130 //
5131 // Ok. All sanity checks passed. Now we're committed to
5132 // loading the new session.
5133 //
5134
5135 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
5136
5137 // See if routes/ip cache need updating
5138 if (new->ip != session[s].ip)
5139 newip++;
5140
5141 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
5142 if (new->route[i].ip != session[s].route[i].ip ||
5143 new->route[i].mask != session[s].route[i].mask)
5144 newip++;
5145
5146 // needs update
5147 if (newip)
5148 {
5149 int routed = 0;
5150
5151 // remove old routes...
5152 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
5153 {
5154 if ((session[s].ip & session[s].route[i].mask) ==
5155 (session[s].route[i].ip & session[s].route[i].mask))
5156 routed++;
5157
5158 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
5159 }
5160
5161 // ...ip
5162 if (session[s].ip)
5163 {
5164 if (session[s].ip_pool_index == -1) // static IP
5165 {
5166 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
5167 }
5168 else // It's part of the IP pool, remove it manually.
5169 uncache_ipmap(session[s].ip);
5170 }
5171
5172 routed = 0;
5173
5174 // add new routes...
5175 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
5176 {
5177 if ((new->ip & new->route[i].mask) ==
5178 (new->route[i].ip & new->route[i].mask))
5179 routed++;
5180
5181 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
5182 }
5183
5184 // ...ip
5185 if (new->ip)
5186 {
5187 // If there's a new one, add it.
5188 if (new->ip_pool_index == -1)
5189 {
5190 if (!routed) routeset(s, new->ip, 0, 0, 1);
5191 }
5192 else
5193 cache_ipmap(new->ip, s);
5194 }
5195 }
5196
5197 // check v6 routing
5198 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
5199 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
5200
5201 // check filters
5202 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
5203 {
5204 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %u\n", (int) new->filter_in);
5205 new->filter_in = 0;
5206 }
5207
5208 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
5209 {
5210 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %u\n", (int) new->filter_out);
5211 new->filter_out = 0;
5212 }
5213
5214 if (new->filter_in != session[s].filter_in)
5215 {
5216 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
5217 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
5218 }
5219
5220 if (new->filter_out != session[s].filter_out)
5221 {
5222 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
5223 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
5224 }
5225
5226 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
5227 // for walking the sessions to forward byte counts to the master.
5228 config->cluster_highest_sessionid = s;
5229
5230 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
5231
5232 // Do fixups into address pool.
5233 if (new->ip_pool_index != -1)
5234 fix_address_pool(s);
5235
5236 return 1;
5237 }
5238
5239 static void initplugins()
5240 {
5241 int i;
5242
5243 loaded_plugins = ll_init();
5244 // Initialize the plugins to nothing
5245 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
5246 plugins[i] = ll_init();
5247 }
5248
5249 static void *open_plugin(char *plugin_name, int load)
5250 {
5251 char path[256] = "";
5252
5253 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
5254 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
5255 return dlopen(path, RTLD_NOW);
5256 }
5257
5258 // plugin callback to get a config value
5259 static void *getconfig(char *key, enum config_typet type)
5260 {
5261 int i;
5262
5263 for (i = 0; config_values[i].key; i++)
5264 {
5265 if (!strcmp(config_values[i].key, key))
5266 {
5267 if (config_values[i].type == type)
5268 return ((void *) config) + config_values[i].offset;
5269
5270 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
5271 key, type, config_values[i].type);
5272
5273 return 0;
5274 }
5275 }
5276
5277 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
5278 return 0;
5279 }
5280
5281 static int add_plugin(char *plugin_name)
5282 {
5283 static struct pluginfuncs funcs = {
5284 _log,
5285 _log_hex,
5286 fmtaddr,
5287 sessionbyuser,
5288 sessiontbysessionidt,
5289 sessionidtbysessiont,
5290 radiusnew,
5291 radiussend,
5292 getconfig,
5293 sessionshutdown,
5294 sessionkill,
5295 throttle_session,
5296 cluster_send_session,
5297 };
5298
5299 void *p = open_plugin(plugin_name, 1);
5300 int (*initfunc)(struct pluginfuncs *);
5301 int i;
5302
5303 if (!p)
5304 {
5305 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
5306 return -1;
5307 }
5308
5309 if (ll_contains(loaded_plugins, p))
5310 {
5311 dlclose(p);
5312 return 0; // already loaded
5313 }
5314
5315 {
5316 int *v = dlsym(p, "plugin_api_version");
5317 if (!v || *v != PLUGIN_API_VERSION)
5318 {
5319 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
5320 dlclose(p);
5321 return -1;
5322 }
5323 }
5324
5325 if ((initfunc = dlsym(p, "plugin_init")))
5326 {
5327 if (!initfunc(&funcs))
5328 {
5329 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
5330 dlclose(p);
5331 return -1;
5332 }
5333 }
5334
5335 ll_push(loaded_plugins, p);
5336
5337 for (i = 0; i < max_plugin_functions; i++)
5338 {
5339 void *x;
5340 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5341 {
5342 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
5343 ll_push(plugins[i], x);
5344 }
5345 }
5346
5347 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
5348 return 1;
5349 }
5350
5351 static void run_plugin_done(void *plugin)
5352 {
5353 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
5354
5355 if (donefunc)
5356 donefunc();
5357 }
5358
5359 static int remove_plugin(char *plugin_name)
5360 {
5361 void *p = open_plugin(plugin_name, 0);
5362 int loaded = 0;
5363
5364 if (!p)
5365 return -1;
5366
5367 if (ll_contains(loaded_plugins, p))
5368 {
5369 int i;
5370 for (i = 0; i < max_plugin_functions; i++)
5371 {
5372 void *x;
5373 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
5374 ll_delete(plugins[i], x);
5375 }
5376
5377 ll_delete(loaded_plugins, p);
5378 run_plugin_done(p);
5379 loaded = 1;
5380 }
5381
5382 dlclose(p);
5383 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
5384 return loaded;
5385 }
5386
5387 int run_plugins(int plugin_type, void *data)
5388 {
5389 int (*func)(void *data);
5390
5391 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
5392 return PLUGIN_RET_ERROR;
5393
5394 ll_reset(plugins[plugin_type]);
5395 while ((func = ll_next(plugins[plugin_type])))
5396 {
5397 int r = func(data);
5398
5399 if (r != PLUGIN_RET_OK)
5400 return r; // stop here
5401 }
5402
5403 return PLUGIN_RET_OK;
5404 }
5405
5406 static void plugins_done()
5407 {
5408 void *p;
5409
5410 ll_reset(loaded_plugins);
5411 while ((p = ll_next(loaded_plugins)))
5412 run_plugin_done(p);
5413 }
5414
5415 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local)
5416 {
5417 struct nsctl request;
5418 struct nsctl response;
5419 int type = unpack_control(&request, buf, len);
5420 int r;
5421 void *p;
5422
5423 if (log_stream && config->debug >= 4)
5424 {
5425 if (type < 0)
5426 {
5427 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
5428 fmtaddr(addr->sin_addr.s_addr, 0), type);
5429 }
5430 else
5431 {
5432 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5433 dump_control(&request, log_stream);
5434 }
5435 }
5436
5437 switch (type)
5438 {
5439 case NSCTL_REQ_LOAD:
5440 if (request.argc != 1)
5441 {
5442 response.type = NSCTL_RES_ERR;
5443 response.argc = 1;
5444 response.argv[0] = "name of plugin required";
5445 }
5446 else if ((r = add_plugin(request.argv[0])) < 1)
5447 {
5448 response.type = NSCTL_RES_ERR;
5449 response.argc = 1;
5450 response.argv[0] = !r
5451 ? "plugin already loaded"
5452 : "error loading plugin";
5453 }
5454 else
5455 {
5456 response.type = NSCTL_RES_OK;
5457 response.argc = 0;
5458 }
5459
5460 break;
5461
5462 case NSCTL_REQ_UNLOAD:
5463 if (request.argc != 1)
5464 {
5465 response.type = NSCTL_RES_ERR;
5466 response.argc = 1;
5467 response.argv[0] = "name of plugin required";
5468 }
5469 else if ((r = remove_plugin(request.argv[0])) < 1)
5470 {
5471 response.type = NSCTL_RES_ERR;
5472 response.argc = 1;
5473 response.argv[0] = !r
5474 ? "plugin not loaded"
5475 : "plugin not found";
5476 }
5477 else
5478 {
5479 response.type = NSCTL_RES_OK;
5480 response.argc = 0;
5481 }
5482
5483 break;
5484
5485 case NSCTL_REQ_HELP:
5486 response.type = NSCTL_RES_OK;
5487 response.argc = 0;
5488
5489 ll_reset(loaded_plugins);
5490 while ((p = ll_next(loaded_plugins)))
5491 {
5492 char **help = dlsym(p, "plugin_control_help");
5493 while (response.argc < 0xff && help && *help)
5494 response.argv[response.argc++] = *help++;
5495 }
5496
5497 break;
5498
5499 case NSCTL_REQ_CONTROL:
5500 {
5501 struct param_control param = {
5502 config->cluster_iam_master,
5503 request.argc,
5504 request.argv,
5505 0,
5506 NULL,
5507 };
5508
5509 int r = run_plugins(PLUGIN_CONTROL, &param);
5510
5511 if (r == PLUGIN_RET_ERROR)
5512 {
5513 response.type = NSCTL_RES_ERR;
5514 response.argc = 1;
5515 response.argv[0] = param.additional
5516 ? param.additional
5517 : "error returned by plugin";
5518 }
5519 else if (r == PLUGIN_RET_NOTMASTER)
5520 {
5521 static char msg[] = "must be run on master: 000.000.000.000";
5522
5523 response.type = NSCTL_RES_ERR;
5524 response.argc = 1;
5525 if (config->cluster_master_address)
5526 {
5527 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5528 response.argv[0] = msg;
5529 }
5530 else
5531 {
5532 response.argv[0] = "must be run on master: none elected";
5533 }
5534 }
5535 else if (!(param.response & NSCTL_RESPONSE))
5536 {
5537 response.type = NSCTL_RES_ERR;
5538 response.argc = 1;
5539 response.argv[0] = param.response
5540 ? "unrecognised response value from plugin"
5541 : "unhandled action";
5542 }
5543 else
5544 {
5545 response.type = param.response;
5546 response.argc = 0;
5547 if (param.additional)
5548 {
5549 response.argc = 1;
5550 response.argv[0] = param.additional;
5551 }
5552 }
5553 }
5554
5555 break;
5556
5557 default:
5558 response.type = NSCTL_RES_ERR;
5559 response.argc = 1;
5560 response.argv[0] = "error unpacking control packet";
5561 }
5562
5563 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5564 if (!buf)
5565 {
5566 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5567 return;
5568 }
5569
5570 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5571 if (r > 0)
5572 {
5573 sendtofrom(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen, local);
5574 if (log_stream && config->debug >= 4)
5575 {
5576 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5577 dump_control(&response, log_stream);
5578 }
5579 }
5580 else
5581 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5582 fmtaddr(addr->sin_addr.s_addr, 0), r);
5583
5584 free(buf);
5585 }
5586
5587 static tunnelidt new_tunnel()
5588 {
5589 tunnelidt i;
5590 for (i = 1; i < MAXTUNNEL; i++)
5591 {
5592 if (tunnel[i].state == TUNNELFREE)
5593 {
5594 LOG(4, 0, i, "Assigning tunnel ID %u\n", i);
5595 if (i > config->cluster_highest_tunnelid)
5596 config->cluster_highest_tunnelid = i;
5597 return i;
5598 }
5599 }
5600 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5601 return 0;
5602 }
5603
5604 //
5605 // We're becoming the master. Do any required setup..
5606 //
5607 // This is principally telling all the plugins that we're
5608 // now a master, and telling them about all the sessions
5609 // that are active too..
5610 //
5611 void become_master(void)
5612 {
5613 int s, i;
5614 static struct event_data d[RADIUS_FDS];
5615 struct epoll_event e;
5616
5617 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5618
5619 // running a bunch of iptables commands is slow and can cause
5620 // the master to drop tunnels on takeover--kludge around the
5621 // problem by forking for the moment (note: race)
5622 if (!fork_and_close())
5623 {
5624 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5625 {
5626 if (!session[s].opened) // Not an in-use session.
5627 continue;
5628
5629 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5630 }
5631 exit(0);
5632 }
5633
5634 // add radius fds
5635 e.events = EPOLLIN;
5636 for (i = 0; i < RADIUS_FDS; i++)
5637 {
5638 d[i].type = FD_TYPE_RADIUS;
5639 d[i].index = i;
5640 e.data.ptr = &d[i];
5641
5642 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5643 }
5644 }
5645
5646 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5647 {
5648 int s, i;
5649 int count = 0;
5650 int buckets[64];
5651
5652 if (CLI_HELP_REQUESTED)
5653 return CLI_HELP_NO_ARGS;
5654
5655 time(&time_now);
5656 for (i = 0; i < 64;++i) buckets[i] = 0;
5657
5658 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5659 {
5660 int idle;
5661 if (!session[s].opened)
5662 continue;
5663
5664 idle = time_now - session[s].last_data;
5665 idle /= 5 ; // In multiples of 5 seconds.
5666 if (idle < 0)
5667 idle = 0;
5668 if (idle > 63)
5669 idle = 63;
5670
5671 ++count;
5672 ++buckets[idle];
5673 }
5674
5675 for (i = 0; i < 63; ++i)
5676 {
5677 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5678 }
5679 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5680 cli_print(cli, "%d total sessions open.", count);
5681 return CLI_OK;
5682 }
5683
5684 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5685 {
5686 int s, i;
5687 int count = 0;
5688 int buckets[64];
5689
5690 if (CLI_HELP_REQUESTED)
5691 return CLI_HELP_NO_ARGS;
5692
5693 time(&time_now);
5694 for (i = 0; i < 64;++i) buckets[i] = 0;
5695
5696 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5697 {
5698 int open = 0, d;
5699 if (!session[s].opened)
5700 continue;
5701
5702 d = time_now - session[s].opened;
5703 if (d < 0)
5704 d = 0;
5705 while (d > 1 && open < 32)
5706 {
5707 ++open;
5708 d >>= 1; // half.
5709 }
5710 ++count;
5711 ++buckets[open];
5712 }
5713
5714 s = 1;
5715 for (i = 0; i < 30; ++i)
5716 {
5717 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5718 s <<= 1;
5719 }
5720 cli_print(cli, "%d total sessions open.", count);
5721 return CLI_OK;
5722 }
5723
5724 /* Unhide an avp.
5725 *
5726 * This unencodes the AVP using the L2TP secret and the previously
5727 * stored random vector. It overwrites the hidden data with the
5728 * unhidden AVP subformat.
5729 */
5730 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5731 {
5732 MD5_CTX ctx;
5733 uint8_t digest[16];
5734 uint8_t *last;
5735 size_t d = 0;
5736 uint16_t m = htons(type);
5737
5738 // Compute initial pad
5739 MD5_Init(&ctx);
5740 MD5_Update(&ctx, (unsigned char *) &m, 2);
5741 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5742 MD5_Update(&ctx, vector, vec_len);
5743 MD5_Final(digest, &ctx);
5744
5745 // pointer to last decoded 16 octets
5746 last = value;
5747
5748 while (len > 0)
5749 {
5750 // calculate a new pad based on the last decoded block
5751 if (d >= sizeof(digest))
5752 {
5753 MD5_Init(&ctx);
5754 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5755 MD5_Update(&ctx, last, sizeof(digest));
5756 MD5_Final(digest, &ctx);
5757
5758 d = 0;
5759 last = value;
5760 }
5761
5762 *value++ ^= digest[d++];
5763 len--;
5764 }
5765 }
5766
5767 int find_filter(char const *name, size_t len)
5768 {
5769 int free = -1;
5770 int i;
5771
5772 for (i = 0; i < MAXFILTER; i++)
5773 {
5774 if (!*ip_filters[i].name)
5775 {
5776 if (free < 0)
5777 free = i;
5778
5779 continue;
5780 }
5781
5782 if (strlen(ip_filters[i].name) != len)
5783 continue;
5784
5785 if (!strncmp(ip_filters[i].name, name, len))
5786 return i;
5787 }
5788
5789 return free;
5790 }
5791
5792 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5793 {
5794 switch (p->op)
5795 {
5796 case FILTER_PORT_OP_EQ: return port == p->port;
5797 case FILTER_PORT_OP_NEQ: return port != p->port;
5798 case FILTER_PORT_OP_GT: return port > p->port;
5799 case FILTER_PORT_OP_LT: return port < p->port;
5800 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5801 }
5802
5803 return 0;
5804 }
5805
5806 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5807 {
5808 switch (op)
5809 {
5810 case FILTER_FLAG_OP_ANY:
5811 return (flags & sflags) || (~flags & cflags);
5812
5813 case FILTER_FLAG_OP_ALL:
5814 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5815
5816 case FILTER_FLAG_OP_EST:
5817 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5818 }
5819
5820 return 0;
5821 }
5822
5823 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5824 {
5825 uint16_t frag_offset;
5826 uint8_t proto;
5827 in_addr_t src_ip;
5828 in_addr_t dst_ip;
5829 uint16_t src_port = 0;
5830 uint16_t dst_port = 0;
5831 uint8_t flags = 0;
5832 ip_filter_rulet *rule;
5833
5834 if (len < 20) // up to end of destination address
5835 return 0;
5836
5837 if ((*buf >> 4) != 4) // IPv4
5838 return 0;
5839
5840 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5841 proto = buf[9];
5842 src_ip = *(in_addr_t *) (buf + 12);
5843 dst_ip = *(in_addr_t *) (buf + 16);
5844
5845 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5846 {
5847 int l = (buf[0] & 0xf) * 4; // length of IP header
5848 if (len < l + 4) // ports
5849 return 0;
5850
5851 src_port = ntohs(*(uint16_t *) (buf + l));
5852 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5853 if (proto == IPPROTO_TCP)
5854 {
5855 if (len < l + 14) // flags
5856 return 0;
5857
5858 flags = buf[l + 13] & 0x3f;
5859 }
5860 }
5861
5862 for (rule = ip_filters[filter].rules; rule->action; rule++)
5863 {
5864 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5865 continue;
5866
5867 if (rule->src_wild != INADDR_BROADCAST &&
5868 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5869 continue;
5870
5871 if (rule->dst_wild != INADDR_BROADCAST &&
5872 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5873 continue;
5874
5875 if (frag_offset)
5876 {
5877 // layer 4 deny rules are skipped
5878 if (rule->action == FILTER_ACTION_DENY &&
5879 (rule->src_ports.op || rule->dst_ports.op || rule->tcp_flag_op))
5880 continue;
5881 }
5882 else
5883 {
5884 if (rule->frag)
5885 continue;
5886
5887 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5888 {
5889 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5890 continue;
5891
5892 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5893 continue;
5894
5895 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5896 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5897 continue;
5898 }
5899 }
5900
5901 // matched
5902 rule->counter++;
5903 return rule->action == FILTER_ACTION_PERMIT;
5904 }
5905
5906 // default deny
5907 return 0;
5908 }