af21f2f481500d0f053569f6b22b249309a8d4ed
[l2tpns.git] / l2tpns.c
1 // L2TP Network Server
2 // Adrian Kennard 2002
3 // Copyright (c) 2003, 2004, 2005 Optus Internet Engineering
4 // Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
5 // vim: sw=8 ts=8
6
7 char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.119 2005-08-10 11:25:56 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
79 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
80
81 static void *ip_hash[256]; // Mapping from IP address to session structures.
82 struct ipv6radix {
83 int sess;
84 struct ipv6radix *branch;
85 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
86
87 // Traffic counters.
88 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
89 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
90 uint32_t eth_tx = 0;
91
92 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
93 time_t time_now = 0; // Current time in seconds since epoch.
94 static char time_now_string[64] = {0}; // Current time as a string.
95 char main_quit = 0; // True if we're in the process of exiting.
96 linked_list *loaded_plugins;
97 linked_list *plugins[MAX_PLUGIN_TYPES];
98
99 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
100 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
101
102 config_descriptt config_values[] = {
103 CONFIG("debug", debug, INT),
104 CONFIG("log_file", log_filename, STRING),
105 CONFIG("pid_file", pid_file, STRING),
106 CONFIG("random_device", random_device, STRING),
107 CONFIG("l2tp_secret", l2tpsecret, STRING),
108 CONFIG("ppp_restart_time", ppp_restart_time, INT),
109 CONFIG("ppp_max_configure", ppp_max_configure, INT),
110 CONFIG("ppp_max_failure", ppp_max_failure, INT),
111 CONFIG("primary_dns", default_dns1, IPv4),
112 CONFIG("secondary_dns", default_dns2, IPv4),
113 CONFIG("primary_radius", radiusserver[0], IPv4),
114 CONFIG("secondary_radius", radiusserver[1], IPv4),
115 CONFIG("primary_radius_port", radiusport[0], SHORT),
116 CONFIG("secondary_radius_port", radiusport[1], SHORT),
117 CONFIG("radius_accounting", radius_accounting, BOOL),
118 CONFIG("radius_interim", radius_interim, INT),
119 CONFIG("radius_secret", radiussecret, STRING),
120 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
121 CONFIG("radius_dae_port", radius_dae_port, SHORT),
122 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
123 CONFIG("bind_address", bind_address, IPv4),
124 CONFIG("peer_address", peer_address, IPv4),
125 CONFIG("send_garp", send_garp, BOOL),
126 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
127 CONFIG("throttle_buckets", num_tbfs, INT),
128 CONFIG("accounting_dir", accounting_dir, STRING),
129 CONFIG("setuid", target_uid, INT),
130 CONFIG("dump_speed", dump_speed, BOOL),
131 CONFIG("multi_read_count", multi_read_count, INT),
132 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
133 CONFIG("lock_pages", lock_pages, BOOL),
134 CONFIG("icmp_rate", icmp_rate, INT),
135 CONFIG("packet_limit", max_packets, INT),
136 CONFIG("cluster_address", cluster_address, IPv4),
137 CONFIG("cluster_interface", cluster_interface, STRING),
138 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
139 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
140 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
141 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
142 { NULL, 0, 0, 0 },
143 };
144
145 static char *plugin_functions[] = {
146 NULL,
147 "plugin_pre_auth",
148 "plugin_post_auth",
149 "plugin_packet_rx",
150 "plugin_packet_tx",
151 "plugin_timer",
152 "plugin_new_session",
153 "plugin_kill_session",
154 "plugin_control",
155 "plugin_radius_response",
156 "plugin_radius_reset",
157 "plugin_become_master",
158 "plugin_new_session_master",
159 };
160
161 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
162
163 // Counters for shutdown sessions
164 static sessiont shut_acct[8192];
165 static sessionidt shut_acct_n = 0;
166
167 tunnelt *tunnel = NULL; // Array of tunnel structures.
168 sessiont *session = NULL; // Array of session structures.
169 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
170 radiust *radius = NULL; // Array of radius structures.
171 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
172 ip_filtert *ip_filters = NULL; // Array of named filters.
173 static controlt *controlfree = 0;
174 struct Tstats *_statistics = NULL;
175 #ifdef RINGBUFFER
176 struct Tringbuffer *ringbuffer = NULL;
177 #endif
178
179 static void cache_ipmap(in_addr_t ip, int s);
180 static void uncache_ipmap(in_addr_t ip);
181 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
182 static void free_ip_address(sessionidt s);
183 static void dump_acct_info(int all);
184 static void sighup_handler(int sig);
185 static void sigalrm_handler(int sig);
186 static void shutdown_handler(int sig);
187 static void sigchild_handler(int sig);
188 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
189 static void update_config(void);
190 static void read_config_file(void);
191 static void initplugins(void);
192 static int add_plugin(char *plugin_name);
193 static int remove_plugin(char *plugin_name);
194 static void plugins_done(void);
195 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
196 static tunnelidt new_tunnel(void);
197 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
198
199 // on slaves, alow BGP to withdraw cleanly before exiting
200 #define QUIT_DELAY 5
201
202 // quit actions (master)
203 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
204 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
205
206 // return internal time (10ths since process startup), set f if given
207 static clockt now(double *f)
208 {
209 struct timeval t;
210 gettimeofday(&t, 0);
211 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
212 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
213 }
214
215 // work out a retry time based on try number
216 // This is a straight bounded exponential backoff.
217 // Maximum re-try time is 32 seconds. (2^5).
218 clockt backoff(uint8_t try)
219 {
220 if (try > 5) try = 5; // max backoff
221 return now(NULL) + 10 * (1 << try);
222 }
223
224
225 //
226 // Log a debug message. Typically called via the LOG macro
227 //
228 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
229 {
230 static char message[65536] = {0};
231 va_list ap;
232
233 #ifdef RINGBUFFER
234 if (ringbuffer)
235 {
236 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
237 ringbuffer->tail = 0;
238 if (ringbuffer->tail == ringbuffer->head)
239 if (++ringbuffer->head >= RINGBUFFER_SIZE)
240 ringbuffer->head = 0;
241
242 ringbuffer->buffer[ringbuffer->tail].level = level;
243 ringbuffer->buffer[ringbuffer->tail].session = s;
244 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
245 va_start(ap, format);
246 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
247 va_end(ap);
248 }
249 #endif
250
251 if (config->debug < level) return;
252
253 va_start(ap, format);
254 vsnprintf(message, sizeof(message), format, ap);
255
256 if (log_stream)
257 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
258 else if (syslog_log)
259 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
260
261 va_end(ap);
262 }
263
264 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
265 {
266 int i, j;
267 const uint8_t *d = data;
268
269 if (config->debug < level) return;
270
271 // No support for _log_hex to syslog
272 if (log_stream)
273 {
274 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
275 setvbuf(log_stream, NULL, _IOFBF, 16384);
276
277 for (i = 0; i < maxsize; )
278 {
279 fprintf(log_stream, "%4X: ", i);
280 for (j = i; j < maxsize && j < (i + 16); j++)
281 {
282 fprintf(log_stream, "%02X ", d[j]);
283 if (j == i + 7)
284 fputs(": ", log_stream);
285 }
286
287 for (; j < i + 16; j++)
288 {
289 fputs(" ", log_stream);
290 if (j == i + 7)
291 fputs(": ", log_stream);
292 }
293
294 fputs(" ", log_stream);
295 for (j = i; j < maxsize && j < (i + 16); j++)
296 {
297 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
298 fputc(d[j], log_stream);
299 else
300 fputc('.', log_stream);
301
302 if (j == i + 7)
303 fputs(" ", log_stream);
304 }
305
306 i = j;
307 fputs("\n", log_stream);
308 }
309
310 fflush(log_stream);
311 setbuf(log_stream, NULL);
312 }
313 }
314
315 // update a counter, accumulating 2^32 wraps
316 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
317 {
318 uint32_t new = *counter + delta;
319 if (new < *counter)
320 (*wrap)++;
321
322 *counter = new;
323 }
324
325 // initialise the random generator
326 static void initrandom(char *source)
327 {
328 static char path[sizeof(config->random_device)] = "*undefined*";
329
330 // reinitialise only if we are forced to do so or if the config has changed
331 if (source && !strncmp(path, source, sizeof(path)))
332 return;
333
334 // close previous source, if any
335 if (rand_fd >= 0)
336 close(rand_fd);
337
338 rand_fd = -1;
339
340 if (source)
341 {
342 // register changes
343 snprintf(path, sizeof(path), "%s", source);
344
345 if (*path == '/')
346 {
347 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
348 if (rand_fd < 0)
349 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
350 path, strerror(errno));
351 }
352 }
353 }
354
355 // fill buffer with random data
356 void random_data(uint8_t *buf, int len)
357 {
358 int n = 0;
359
360 CSTAT(random_data);
361 if (rand_fd >= 0)
362 {
363 n = read(rand_fd, buf, len);
364 if (n >= len) return;
365 if (n < 0)
366 {
367 if (errno != EAGAIN)
368 {
369 LOG(0, 0, 0, "Error reading from random source: %s\n",
370 strerror(errno));
371
372 // fall back to rand()
373 initrandom(NULL);
374 }
375
376 n = 0;
377 }
378 }
379
380 // append missing data
381 while (n < len)
382 // not using the low order bits from the prng stream
383 buf[n++] = (rand() >> 4) & 0xff;
384 }
385
386 // Add a route
387 //
388 // This adds it to the routing table, advertises it
389 // via BGP if enabled, and stuffs it into the
390 // 'sessionbyip' cache.
391 //
392 // 'ip' and 'mask' must be in _host_ order.
393 //
394 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
395 {
396 struct rtentry r;
397 int i;
398
399 if (!mask) mask = 0xffffffff;
400
401 ip &= mask; // Force the ip to be the first one in the route.
402
403 memset(&r, 0, sizeof(r));
404 r.rt_dev = config->tundevice;
405 r.rt_dst.sa_family = AF_INET;
406 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
407 r.rt_gateway.sa_family = AF_INET;
408 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
409 r.rt_genmask.sa_family = AF_INET;
410 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
411 r.rt_flags = (RTF_UP | RTF_STATIC);
412 if (gw)
413 r.rt_flags |= RTF_GATEWAY;
414 else if (mask == 0xffffffff)
415 r.rt_flags |= RTF_HOST;
416
417 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
418 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
419 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
420
421 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
422 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
423
424 #ifdef BGP
425 if (add)
426 bgp_add_route(htonl(ip), htonl(mask));
427 else
428 bgp_del_route(htonl(ip), htonl(mask));
429 #endif /* BGP */
430
431 // Add/Remove the IPs to the 'sessionbyip' cache.
432 // Note that we add the zero address in the case of
433 // a network route. Roll on CIDR.
434
435 // Note that 's == 0' implies this is the address pool.
436 // We still cache it here, because it will pre-fill
437 // the malloc'ed tree.
438
439 if (s)
440 {
441 if (!add) // Are we deleting a route?
442 s = 0; // Caching the session as '0' is the same as uncaching.
443
444 for (i = ip; (i&mask) == (ip&mask) ; ++i)
445 cache_ipmap(i, s);
446 }
447 }
448
449 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
450 {
451 struct in6_rtmsg rt;
452 char ipv6addr[INET6_ADDRSTRLEN];
453
454 if (ifr6fd < 0)
455 {
456 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
457 return;
458 }
459
460 memset(&rt, 0, sizeof(rt));
461
462 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
463 rt.rtmsg_dst_len = prefixlen;
464 rt.rtmsg_metric = 1;
465 rt.rtmsg_flags = RTF_UP;
466 rt.rtmsg_ifindex = tunidx;
467
468 LOG(1, 0, 0, "Route %s %s/%d\n",
469 add ? "add" : "del",
470 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
471 prefixlen);
472
473 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
474 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
475 strerror(errno));
476
477 // FIXME: need to add BGP routing (RFC2858)
478
479 if (s)
480 {
481 if (!add) // Are we deleting a route?
482 s = 0; // Caching the session as '0' is the same as uncaching.
483
484 cache_ipv6map(ip, prefixlen, s);
485 }
486
487 return;
488 }
489
490 // defined in linux/ipv6.h, but tricky to include from user-space
491 // TODO: move routing to use netlink rather than ioctl
492 struct in6_ifreq {
493 struct in6_addr ifr6_addr;
494 __u32 ifr6_prefixlen;
495 unsigned int ifr6_ifindex;
496 };
497
498 //
499 // Set up TUN interface
500 static void inittun(void)
501 {
502 struct ifreq ifr;
503 struct in6_ifreq ifr6;
504 struct sockaddr_in sin = {0};
505 memset(&ifr, 0, sizeof(ifr));
506 ifr.ifr_flags = IFF_TUN;
507
508 tunfd = open(TUNDEVICE, O_RDWR);
509 if (tunfd < 0)
510 { // fatal
511 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
512 exit(1);
513 }
514 {
515 int flags = fcntl(tunfd, F_GETFL, 0);
516 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
517 }
518 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
519 {
520 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
521 exit(1);
522 }
523 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
524 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
525 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
526
527 sin.sin_family = AF_INET;
528 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
529 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
530
531 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
532 {
533 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
534 exit(1);
535 }
536 /* Bump up the qlen to deal with bursts from the network */
537 ifr.ifr_qlen = 1000;
538 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
539 {
540 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
541 exit(1);
542 }
543 ifr.ifr_flags = IFF_UP;
544 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
545 {
546 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
547 exit(1);
548 }
549 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
550 {
551 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
552 exit(1);
553 }
554 tunidx = ifr.ifr_ifindex;
555
556 // Only setup IPv6 on the tun device if we have a configured prefix
557 if (config->ipv6_prefix.s6_addr[0]) {
558 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
559
560 // Link local address is FE80::1
561 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
562 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
563 ifr6.ifr6_addr.s6_addr[1] = 0x80;
564 ifr6.ifr6_addr.s6_addr[15] = 1;
565 ifr6.ifr6_prefixlen = 64;
566 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
567 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
568 {
569 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
570 " %s\n", strerror(errno));
571 }
572
573 // Global address is prefix::1
574 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
575 ifr6.ifr6_addr = config->ipv6_prefix;
576 ifr6.ifr6_addr.s6_addr[15] = 1;
577 ifr6.ifr6_prefixlen = 64;
578 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
579 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
580 {
581 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
582 strerror(errno));
583 }
584 }
585 }
586
587 // set up UDP ports
588 static void initudp(void)
589 {
590 int on = 1;
591 struct sockaddr_in addr;
592
593 // Tunnel
594 memset(&addr, 0, sizeof(addr));
595 addr.sin_family = AF_INET;
596 addr.sin_port = htons(L2TPPORT);
597 addr.sin_addr.s_addr = config->bind_address;
598 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
599 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
600 {
601 int flags = fcntl(udpfd, F_GETFL, 0);
602 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
603 }
604 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
605 {
606 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
607 exit(1);
608 }
609
610 // Control
611 memset(&addr, 0, sizeof(addr));
612 addr.sin_family = AF_INET;
613 addr.sin_port = htons(NSCTL_PORT);
614 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
615 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
616 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
617 {
618 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
619 exit(1);
620 }
621
622 // Dynamic Authorization Extensions to RADIUS
623 memset(&addr, 0, sizeof(addr));
624 addr.sin_family = AF_INET;
625 addr.sin_port = htons(config->radius_dae_port);
626 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
627 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
628 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
629 {
630 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
631 exit(1);
632 }
633
634 // Intercept
635 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
636 }
637
638 //
639 // Find session by IP, < 1 for not found
640 //
641 // Confusingly enough, this 'ip' must be
642 // in _network_ order. This being the common
643 // case when looking it up from IP packet headers.
644 //
645 // We actually use this cache for two things.
646 // #1. For used IP addresses, this maps to the
647 // session ID that it's used by.
648 // #2. For un-used IP addresses, this maps to the
649 // index into the pool table that contains that
650 // IP address.
651 //
652
653 static int lookup_ipmap(in_addr_t ip)
654 {
655 uint8_t *a = (uint8_t *) &ip;
656 uint8_t **d = (uint8_t **) ip_hash;
657
658 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
659 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
660 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
661
662 return (int) (intptr_t) d[(size_t) *a];
663 }
664
665 static int lookup_ipv6map(struct in6_addr ip)
666 {
667 struct ipv6radix *curnode;
668 int i;
669 int s;
670 char ipv6addr[INET6_ADDRSTRLEN];
671
672 curnode = &ipv6_hash[ip.s6_addr[0]];
673 i = 1;
674 s = curnode->sess;
675
676 while (s == 0 && i < 15 && curnode->branch != NULL)
677 {
678 curnode = &curnode->branch[ip.s6_addr[i]];
679 s = curnode->sess;
680 i++;
681 }
682
683 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
684 inet_ntop(AF_INET6, &ip, ipv6addr,
685 INET6_ADDRSTRLEN),
686 s);
687
688 return s;
689 }
690
691 sessionidt sessionbyip(in_addr_t ip)
692 {
693 int s = lookup_ipmap(ip);
694 CSTAT(sessionbyip);
695
696 if (s > 0 && s < MAXSESSION && session[s].opened)
697 return (sessionidt) s;
698
699 return 0;
700 }
701
702 sessionidt sessionbyipv6(struct in6_addr ip)
703 {
704 int s;
705 CSTAT(sessionbyipv6);
706
707 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
708 (ip.s6_addr[0] == 0xFE &&
709 ip.s6_addr[1] == 0x80 &&
710 ip.s6_addr16[1] == 0 &&
711 ip.s6_addr16[2] == 0 &&
712 ip.s6_addr16[3] == 0)) {
713 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
714 } else {
715 s = lookup_ipv6map(ip);
716 }
717
718 if (s > 0 && s < MAXSESSION && session[s].opened)
719 return s;
720
721 return 0;
722 }
723
724 //
725 // Take an IP address in HOST byte order and
726 // add it to the sessionid by IP cache.
727 //
728 // (It's actually cached in network order)
729 //
730 static void cache_ipmap(in_addr_t ip, int s)
731 {
732 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
733 uint8_t *a = (uint8_t *) &nip;
734 uint8_t **d = (uint8_t **) ip_hash;
735 int i;
736
737 for (i = 0; i < 3; i++)
738 {
739 if (!d[(size_t) a[i]])
740 {
741 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
742 return;
743 }
744
745 d = (uint8_t **) d[(size_t) a[i]];
746 }
747
748 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
749
750 if (s > 0)
751 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
752
753 else if (s == 0)
754 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
755 // else a map to an ip pool index.
756 }
757
758 static void uncache_ipmap(in_addr_t ip)
759 {
760 cache_ipmap(ip, 0); // Assign it to the NULL session.
761 }
762
763 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
764 {
765 int i;
766 int bytes;
767 struct ipv6radix *curnode;
768 char ipv6addr[INET6_ADDRSTRLEN];
769
770 curnode = &ipv6_hash[ip.s6_addr[0]];
771
772 bytes = prefixlen >> 3;
773 i = 1;
774 while (i < bytes) {
775 if (curnode->branch == NULL)
776 {
777 if (!(curnode->branch = calloc(256,
778 sizeof (struct ipv6radix))))
779 return;
780 }
781 curnode = &curnode->branch[ip.s6_addr[i]];
782 i++;
783 }
784
785 curnode->sess = s;
786
787 if (s > 0)
788 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
789 inet_ntop(AF_INET6, &ip, ipv6addr,
790 INET6_ADDRSTRLEN),
791 prefixlen);
792 else if (s == 0)
793 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
794 inet_ntop(AF_INET6, &ip, ipv6addr,
795 INET6_ADDRSTRLEN),
796 prefixlen);
797 }
798
799 //
800 // CLI list to dump current ipcache.
801 //
802 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
803 {
804 char **d = (char **) ip_hash, **e, **f, **g;
805 int i, j, k, l;
806 int count = 0;
807
808 if (CLI_HELP_REQUESTED)
809 return CLI_HELP_NO_ARGS;
810
811 cli_print(cli, "%7s %s", "Sess#", "IP Address");
812
813 for (i = 0; i < 256; ++i)
814 {
815 if (!d[i])
816 continue;
817 e = (char **) d[i];
818 for (j = 0; j < 256; ++j)
819 {
820 if (!e[j])
821 continue;
822 f = (char **) e[j];
823 for (k = 0; k < 256; ++k)
824 {
825 if (!f[k])
826 continue;
827 g = (char **)f[k];
828 for (l = 0; l < 256; ++l)
829 {
830 if (!g[l])
831 continue;
832 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
833 ++count;
834 }
835 }
836 }
837 }
838 cli_print(cli, "%d entries in cache", count);
839 return CLI_OK;
840 }
841
842
843 // Find session by username, 0 for not found
844 // walled garden users aren't authenticated, so the username is
845 // reasonably useless. Ignore them to avoid incorrect actions
846 //
847 // This is VERY inefficent. Don't call it often. :)
848 //
849 sessionidt sessionbyuser(char *username)
850 {
851 int s;
852 CSTAT(sessionbyuser);
853
854 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
855 {
856 if (!session[s].opened)
857 continue;
858
859 if (session[s].walled_garden)
860 continue; // Skip walled garden users.
861
862 if (!strncmp(session[s].user, username, 128))
863 return s;
864
865 }
866 return 0; // Not found.
867 }
868
869 void send_garp(in_addr_t ip)
870 {
871 int s;
872 struct ifreq ifr;
873 uint8_t mac[6];
874
875 s = socket(PF_INET, SOCK_DGRAM, 0);
876 if (s < 0)
877 {
878 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
879 return;
880 }
881 memset(&ifr, 0, sizeof(ifr));
882 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
883 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
884 {
885 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
886 close(s);
887 return;
888 }
889 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
890 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
891 {
892 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
893 close(s);
894 return;
895 }
896 close(s);
897 sendarp(ifr.ifr_ifindex, mac, ip);
898 }
899
900 static sessiont *sessiontbysessionidt(sessionidt s)
901 {
902 if (!s || s >= MAXSESSION) return NULL;
903 return &session[s];
904 }
905
906 static sessionidt sessionidtbysessiont(sessiont *s)
907 {
908 sessionidt val = s-session;
909 if (s < session || val >= MAXSESSION) return 0;
910 return val;
911 }
912
913 // actually send a control message for a specific tunnel
914 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
915 {
916 struct sockaddr_in addr;
917
918 CSTAT(tunnelsend);
919
920 if (!t)
921 {
922 static int backtrace_count = 0;
923 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
924 STAT(tunnel_tx_errors);
925 log_backtrace(backtrace_count, 5)
926 return;
927 }
928
929 if (!tunnel[t].ip)
930 {
931 static int backtrace_count = 0;
932 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
933 log_backtrace(backtrace_count, 5)
934 STAT(tunnel_tx_errors);
935 return;
936 }
937
938 memset(&addr, 0, sizeof(addr));
939 addr.sin_family = AF_INET;
940 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
941 addr.sin_port = htons(tunnel[t].port);
942
943 // sequence expected, if sequence in message
944 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
945
946 // If this is a control message, deal with retries
947 if (*buf & 0x80)
948 {
949 tunnel[t].last = time_now; // control message sent
950 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
951 if (tunnel[t].try > 1)
952 {
953 STAT(tunnel_retries);
954 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
955 }
956 }
957
958 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
959 {
960 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
961 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
962 STAT(tunnel_tx_errors);
963 return;
964 }
965
966 LOG_HEX(5, "Send Tunnel Data", buf, l);
967 STAT(tunnel_tx_packets);
968 INC_STAT(tunnel_tx_bytes, l);
969 }
970
971 //
972 // Tiny helper function to write data to
973 // the 'tun' device.
974 //
975 int tun_write(uint8_t * data, int size)
976 {
977 return write(tunfd, data, size);
978 }
979
980 // process outgoing (to tunnel) IP
981 //
982 static void processipout(uint8_t *buf, int len)
983 {
984 sessionidt s;
985 sessiont *sp;
986 tunnelidt t;
987 in_addr_t ip;
988
989 uint8_t *data = buf; // Keep a copy of the originals.
990 int size = len;
991
992 uint8_t b[MAXETHER + 20];
993
994 CSTAT(processipout);
995
996 if (len < MIN_IP_SIZE)
997 {
998 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
999 STAT(tun_rx_errors);
1000 return;
1001 }
1002 if (len >= MAXETHER)
1003 {
1004 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1005 STAT(tun_rx_errors);
1006 return;
1007 }
1008
1009 // Skip the tun header
1010 buf += 4;
1011 len -= 4;
1012
1013 // Got an IP header now
1014 if (*(uint8_t *)(buf) >> 4 != 4)
1015 {
1016 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1017 return;
1018 }
1019
1020 ip = *(uint32_t *)(buf + 16);
1021 if (!(s = sessionbyip(ip)))
1022 {
1023 // Is this a packet for a session that doesn't exist?
1024 static int rate = 0; // Number of ICMP packets we've sent this second.
1025 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1026
1027 if (last != time_now)
1028 {
1029 last = time_now;
1030 rate = 0;
1031 }
1032
1033 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1034 {
1035 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1036 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1037 config->bind_address ? config->bind_address : my_address, buf, len);
1038 }
1039 return;
1040 }
1041 t = session[s].tunnel;
1042 sp = &session[s];
1043
1044 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1045 if (config->max_packets > 0)
1046 {
1047 if (sess_local[s].last_packet_out == TIME)
1048 {
1049 int max = config->max_packets;
1050
1051 // All packets for throttled sessions are handled by the
1052 // master, so further limit by using the throttle rate.
1053 // A bit of a kludge, since throttle rate is in kbps,
1054 // but should still be generous given our average DSL
1055 // packet size is 200 bytes: a limit of 28kbps equates
1056 // to around 180 packets per second.
1057 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1058 max = sp->throttle_out;
1059
1060 if (++sess_local[s].packets_out > max)
1061 {
1062 sess_local[s].packets_dropped++;
1063 return;
1064 }
1065 }
1066 else
1067 {
1068 if (sess_local[s].packets_dropped)
1069 {
1070 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1071 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1072 sess_local[s].packets_dropped, sess_local[s].packets_out,
1073 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1074 sp->user);
1075 }
1076
1077 sess_local[s].last_packet_out = TIME;
1078 sess_local[s].packets_out = 1;
1079 sess_local[s].packets_dropped = 0;
1080 }
1081 }
1082
1083 // run access-list if any
1084 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1085 return;
1086
1087 if (sp->tbf_out)
1088 {
1089 // Are we throttling this session?
1090 if (config->cluster_iam_master)
1091 tbf_queue_packet(sp->tbf_out, data, size);
1092 else
1093 master_throttle_packet(sp->tbf_out, data, size);
1094 return;
1095 }
1096 else if (sp->walled_garden && !config->cluster_iam_master)
1097 {
1098 // We are walled-gardening this
1099 master_garden_packet(s, data, size);
1100 return;
1101 }
1102
1103 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1104
1105 // Add on L2TP header
1106 {
1107 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1108 if (!p) return;
1109 tunnelsend(b, len + (p-b), t); // send it...
1110 }
1111
1112 // Snooping this session, send it to intercept box
1113 if (sp->snoop_ip && sp->snoop_port)
1114 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1115
1116 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1117 sp->cout_delta += len;
1118 sp->pout++;
1119 udp_tx += len;
1120
1121 sess_local[s].cout += len; // To send to master..
1122 sess_local[s].pout++;
1123 }
1124
1125 // process outgoing (to tunnel) IPv6
1126 //
1127 static void processipv6out(uint8_t * buf, int len)
1128 {
1129 sessionidt s;
1130 sessiont *sp;
1131 tunnelidt t;
1132 in_addr_t ip;
1133 struct in6_addr ip6;
1134
1135 uint8_t *data = buf; // Keep a copy of the originals.
1136 int size = len;
1137
1138 uint8_t b[MAXETHER + 20];
1139
1140 CSTAT(processipv6out);
1141
1142 if (len < MIN_IP_SIZE)
1143 {
1144 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1145 STAT(tunnel_tx_errors);
1146 return;
1147 }
1148 if (len >= MAXETHER)
1149 {
1150 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1151 STAT(tunnel_tx_errors);
1152 return;
1153 }
1154
1155 // Skip the tun header
1156 buf += 4;
1157 len -= 4;
1158
1159 // Got an IP header now
1160 if (*(uint8_t *)(buf) >> 4 != 6)
1161 {
1162 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1163 return;
1164 }
1165
1166 ip6 = *(struct in6_addr *)(buf+24);
1167 s = sessionbyipv6(ip6);
1168
1169 if (s == 0)
1170 {
1171 ip = *(uint32_t *)(buf + 32);
1172 s = sessionbyip(ip);
1173 }
1174
1175 if (s == 0)
1176 {
1177 // Is this a packet for a session that doesn't exist?
1178 static int rate = 0; // Number of ICMP packets we've sent this second.
1179 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1180
1181 if (last != time_now)
1182 {
1183 last = time_now;
1184 rate = 0;
1185 }
1186
1187 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1188 {
1189 // FIXME: Should send icmp6 host unreachable
1190 }
1191 return;
1192 }
1193 t = session[s].tunnel;
1194 sp = &session[s];
1195
1196 // FIXME: add DoS prevention/filters?
1197
1198 if (sp->tbf_out)
1199 {
1200 // Are we throttling this session?
1201 if (config->cluster_iam_master)
1202 tbf_queue_packet(sp->tbf_out, data, size);
1203 else
1204 master_throttle_packet(sp->tbf_out, data, size);
1205 return;
1206 }
1207 else if (sp->walled_garden && !config->cluster_iam_master)
1208 {
1209 // We are walled-gardening this
1210 master_garden_packet(s, data, size);
1211 return;
1212 }
1213
1214 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1215
1216 // Add on L2TP header
1217 {
1218 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1219 if (!p) return;
1220 tunnelsend(b, len + (p-b), t); // send it...
1221 }
1222
1223 // Snooping this session, send it to intercept box
1224 if (sp->snoop_ip && sp->snoop_port)
1225 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1226
1227 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1228 sp->cout_delta += len;
1229 sp->pout++;
1230 udp_tx += len;
1231
1232 sess_local[s].cout += len; // To send to master..
1233 sess_local[s].pout++;
1234 }
1235
1236 //
1237 // Helper routine for the TBF filters.
1238 // Used to send queued data in to the user!
1239 //
1240 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1241 {
1242 sessiont *sp;
1243 tunnelidt t;
1244 in_addr_t ip;
1245
1246 uint8_t b[MAXETHER + 20];
1247
1248 if (len < 0 || len > MAXETHER)
1249 {
1250 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1251 return;
1252 }
1253
1254 // Skip the tun header
1255 buf += 4;
1256 len -= 4;
1257
1258 ip = *(in_addr_t *)(buf + 16);
1259
1260 if (!session[s].ip)
1261 return;
1262
1263 t = session[s].tunnel;
1264 sp = &session[s];
1265
1266 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1267
1268 // Add on L2TP header
1269 {
1270 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1271 if (!p) return;
1272 tunnelsend(b, len + (p-b), t); // send it...
1273 }
1274
1275 // Snooping this session.
1276 if (sp->snoop_ip && sp->snoop_port)
1277 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1278
1279 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1280 sp->cout_delta += len;
1281 sp->pout++;
1282 udp_tx += len;
1283
1284 sess_local[s].cout += len; // To send to master..
1285 sess_local[s].pout++;
1286 }
1287
1288 // add an AVP (16 bit)
1289 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1290 {
1291 uint16_t l = (m ? 0x8008 : 0x0008);
1292 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1293 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1294 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1295 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1296 c->length += 8;
1297 }
1298
1299 // add an AVP (32 bit)
1300 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1301 {
1302 uint16_t l = (m ? 0x800A : 0x000A);
1303 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1304 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1305 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1306 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1307 c->length += 10;
1308 }
1309
1310 // add an AVP (string)
1311 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1312 {
1313 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1314 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1315 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1316 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1317 memcpy(c->buf + c->length + 6, val, strlen(val));
1318 c->length += 6 + strlen(val);
1319 }
1320
1321 // add a binary AVP
1322 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1323 {
1324 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1325 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1326 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1327 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1328 memcpy(c->buf + c->length + 6, val, len);
1329 c->length += 6 + len;
1330 }
1331
1332 // new control connection
1333 static controlt *controlnew(uint16_t mtype)
1334 {
1335 controlt *c;
1336 if (!controlfree)
1337 c = malloc(sizeof(controlt));
1338 else
1339 {
1340 c = controlfree;
1341 controlfree = c->next;
1342 }
1343 assert(c);
1344 c->next = 0;
1345 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1346 c->length = 12;
1347 control16(c, 0, mtype, 1);
1348 return c;
1349 }
1350
1351 // send zero block if nothing is waiting
1352 // (ZLB send).
1353 static void controlnull(tunnelidt t)
1354 {
1355 uint8_t buf[12];
1356 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1357 return;
1358
1359 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1360 *(uint16_t *) (buf + 2) = htons(12); // length
1361 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1362 *(uint16_t *) (buf + 6) = htons(0); // session
1363 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1364 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1365 tunnelsend(buf, 12, t);
1366 }
1367
1368 // add a control message to a tunnel, and send if within window
1369 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1370 {
1371 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1372 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1373 *(uint16_t *) (c->buf + 6) = htons(far); // session
1374 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1375 tunnel[t].ns++; // advance sequence
1376 // link in message in to queue
1377 if (tunnel[t].controlc)
1378 tunnel[t].controle->next = c;
1379 else
1380 tunnel[t].controls = c;
1381
1382 tunnel[t].controle = c;
1383 tunnel[t].controlc++;
1384
1385 // send now if space in window
1386 if (tunnel[t].controlc <= tunnel[t].window)
1387 {
1388 tunnel[t].try = 0; // first send
1389 tunnelsend(c->buf, c->length, t);
1390 }
1391 }
1392
1393 //
1394 // Throttle or Unthrottle a session
1395 //
1396 // Throttle the data from/to through a session to no more than
1397 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1398 // user).
1399 //
1400 // If either value is -1, the current value is retained for that
1401 // direction.
1402 //
1403 void throttle_session(sessionidt s, int rate_in, int rate_out)
1404 {
1405 if (!session[s].opened)
1406 return; // No-one home.
1407
1408 if (!*session[s].user)
1409 return; // User not logged in
1410
1411 if (rate_in >= 0)
1412 {
1413 int bytes = rate_in * 1024 / 8; // kbits to bytes
1414 if (session[s].tbf_in)
1415 free_tbf(session[s].tbf_in);
1416
1417 if (rate_in > 0)
1418 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1419 else
1420 session[s].tbf_in = 0;
1421
1422 session[s].throttle_in = rate_in;
1423 }
1424
1425 if (rate_out >= 0)
1426 {
1427 int bytes = rate_out * 1024 / 8;
1428 if (session[s].tbf_out)
1429 free_tbf(session[s].tbf_out);
1430
1431 if (rate_out > 0)
1432 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1433 else
1434 session[s].tbf_out = 0;
1435
1436 session[s].throttle_out = rate_out;
1437 }
1438 }
1439
1440 // add/remove filters from session (-1 = no change)
1441 void filter_session(sessionidt s, int filter_in, int filter_out)
1442 {
1443 if (!session[s].opened)
1444 return; // No-one home.
1445
1446 if (!*session[s].user)
1447 return; // User not logged in
1448
1449 // paranoia
1450 if (filter_in > MAXFILTER) filter_in = -1;
1451 if (filter_out > MAXFILTER) filter_out = -1;
1452 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1453 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1454
1455 if (filter_in >= 0)
1456 {
1457 if (session[s].filter_in)
1458 ip_filters[session[s].filter_in - 1].used--;
1459
1460 if (filter_in > 0)
1461 ip_filters[filter_in - 1].used++;
1462
1463 session[s].filter_in = filter_in;
1464 }
1465
1466 if (filter_out >= 0)
1467 {
1468 if (session[s].filter_out)
1469 ip_filters[session[s].filter_out - 1].used--;
1470
1471 if (filter_out > 0)
1472 ip_filters[filter_out - 1].used++;
1473
1474 session[s].filter_out = filter_out;
1475 }
1476 }
1477
1478 // start tidy shutdown of session
1479 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1480 {
1481 int walled_garden = session[s].walled_garden;
1482
1483
1484 CSTAT(sessionshutdown);
1485
1486 if (!session[s].opened)
1487 {
1488 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1489 return; // not a live session
1490 }
1491
1492 if (!session[s].die)
1493 {
1494 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1495 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1496 run_plugins(PLUGIN_KILL_SESSION, &data);
1497 }
1498
1499 if (session[s].ip && !walled_garden && !session[s].die)
1500 {
1501 // RADIUS Stop message
1502 uint16_t r = radiusnew(s);
1503 if (r)
1504 {
1505 // stop, if not already trying
1506 if (radius[r].state != RADIUSSTOP)
1507 radiussend(r, RADIUSSTOP);
1508 }
1509 else
1510 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1511
1512 // Save counters to dump to accounting file
1513 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1514 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1515 }
1516
1517 if (session[s].ip)
1518 { // IP allocated, clear and unroute
1519 int r;
1520 int routed = 0;
1521 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1522 {
1523 if ((session[s].ip & session[s].route[r].mask) ==
1524 (session[s].route[r].ip & session[s].route[r].mask))
1525 routed++;
1526
1527 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1528 session[s].route[r].ip = 0;
1529 }
1530
1531 if (session[s].ip_pool_index == -1) // static ip
1532 {
1533 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1534 session[s].ip = 0;
1535 }
1536 else
1537 free_ip_address(s);
1538
1539 // unroute IPv6, if setup
1540 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1541 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1542 }
1543
1544 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1545 throttle_session(s, 0, 0);
1546
1547 if (result)
1548 { // Send CDN
1549 controlt *c = controlnew(14); // sending CDN
1550 if (error)
1551 {
1552 uint8_t buf[4];
1553 *(uint16_t *) buf = htons(result);
1554 *(uint16_t *) (buf+2) = htons(error);
1555 controlb(c, 1, buf, 4, 1);
1556 }
1557 else
1558 control16(c, 1, result, 1);
1559
1560 control16(c, 14, s, 1); // assigned session (our end)
1561 controladd(c, session[s].far, session[s].tunnel); // send the message
1562 }
1563
1564 if (!session[s].die)
1565 session[s].die = TIME + 150; // Clean up in 15 seconds
1566
1567 // update filter refcounts
1568 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1569 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1570
1571 // clear PPP state
1572 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1573 sess_local[s].lcp.restart = 0;
1574 sess_local[s].ipcp.restart = 0;
1575 sess_local[s].ipv6cp.restart = 0;
1576 sess_local[s].ccp.restart = 0;
1577
1578 cluster_send_session(s);
1579 }
1580
1581 void sendipcp(sessionidt s, tunnelidt t)
1582 {
1583 uint8_t buf[MAXCONTROL];
1584 uint8_t *q;
1585
1586 CSTAT(sendipcp);
1587
1588 if (!session[s].unique_id)
1589 {
1590 if (!++last_id) ++last_id; // skip zero
1591 session[s].unique_id = last_id;
1592 }
1593
1594 q = makeppp(buf,sizeof(buf), 0, 0, s, t, PPPIPCP);
1595 if (!q) return;
1596
1597 *q = ConfigReq;
1598 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1599 *(uint16_t *) (q + 2) = htons(10); // packet length
1600 q[4] = 3; // ip address option
1601 q[5] = 6; // option length
1602 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1603 config->bind_address ? config->bind_address :
1604 my_address; // send my IP
1605
1606 tunnelsend(buf, 10 + (q - buf), t); // send it
1607 }
1608
1609 void sendipv6cp(sessionidt s, tunnelidt t)
1610 {
1611 uint8_t buf[MAXCONTROL];
1612 uint8_t *q;
1613
1614 CSTAT(sendipv6cp);
1615
1616 q = makeppp(buf,sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1617 if (!q) return;
1618
1619 *q = ConfigReq;
1620 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1621 // only send one type
1622 // of request
1623 *(uint16_t *) (q + 2) = htons(14);
1624 q[4] = 1; // interface identifier option
1625 q[5] = 10; // option length
1626 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1627 *(uint32_t *) (q + 10) = 0;
1628 q[13] = 1;
1629
1630 tunnelsend(buf, 14 + (q - buf), t); // send it
1631 }
1632
1633 static void sessionclear(sessionidt s)
1634 {
1635 memset(&session[s], 0, sizeof(session[s]));
1636 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1637 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1638
1639 session[s].tunnel = T_FREE; // Mark it as free.
1640 session[s].next = sessionfree;
1641 sessionfree = s;
1642 }
1643
1644 // kill a session now
1645 void sessionkill(sessionidt s, char *reason)
1646 {
1647
1648 CSTAT(sessionkill);
1649
1650 if (!session[s].opened) // not alive
1651 return;
1652
1653 if (session[s].next)
1654 {
1655 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1656 return;
1657 }
1658
1659 session[s].die = TIME;
1660 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1661 if (sess_local[s].radius)
1662 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1663
1664 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1665 sessionclear(s);
1666 cluster_send_session(s);
1667 }
1668
1669 static void tunnelclear(tunnelidt t)
1670 {
1671 if (!t) return;
1672 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1673 tunnel[t].state = TUNNELFREE;
1674 }
1675
1676 // kill a tunnel now
1677 static void tunnelkill(tunnelidt t, char *reason)
1678 {
1679 sessionidt s;
1680 controlt *c;
1681
1682 CSTAT(tunnelkill);
1683
1684 tunnel[t].state = TUNNELDIE;
1685
1686 // free control messages
1687 while ((c = tunnel[t].controls))
1688 {
1689 controlt * n = c->next;
1690 tunnel[t].controls = n;
1691 tunnel[t].controlc--;
1692 c->next = controlfree;
1693 controlfree = c;
1694 }
1695 // kill sessions
1696 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1697 if (session[s].tunnel == t)
1698 sessionkill(s, reason);
1699
1700 // free tunnel
1701 tunnelclear(t);
1702 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1703 cli_tunnel_actions[t].action = 0;
1704 cluster_send_tunnel(t);
1705 }
1706
1707 // shut down a tunnel cleanly
1708 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1709 {
1710 sessionidt s;
1711
1712 CSTAT(tunnelshutdown);
1713
1714 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1715 {
1716 // never set up, can immediately kill
1717 tunnelkill(t, reason);
1718 return;
1719 }
1720 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1721
1722 // close session
1723 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1724 if (session[s].tunnel == t)
1725 sessionshutdown(s, reason, 0, 0);
1726
1727 tunnel[t].state = TUNNELDIE;
1728 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1729 cluster_send_tunnel(t);
1730 // TBA - should we wait for sessions to stop?
1731 if (result)
1732 {
1733 controlt *c = controlnew(4); // sending StopCCN
1734 if (error)
1735 {
1736 uint8_t buf[64];
1737 int l = 4;
1738 *(uint16_t *) buf = htons(result);
1739 *(uint16_t *) (buf+2) = htons(error);
1740 if (msg)
1741 {
1742 int m = strlen(msg);
1743 if (m + 4 > sizeof(buf))
1744 m = sizeof(buf) - 4;
1745
1746 memcpy(buf+4, msg, m);
1747 l += m;
1748 }
1749
1750 controlb(c, 1, buf, l, 1);
1751 }
1752 else
1753 control16(c, 1, result, 1);
1754
1755 control16(c, 9, t, 1); // assigned tunnel (our end)
1756 controladd(c, 0, t); // send the message
1757 }
1758 }
1759
1760 // read and process packet on tunnel (UDP)
1761 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1762 {
1763 uint8_t *chapresponse = NULL;
1764 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1765 uint8_t *p = buf + 2;
1766
1767
1768 CSTAT(processudp);
1769
1770 udp_rx += len;
1771 udp_rx_pkt++;
1772 LOG_HEX(5, "UDP Data", buf, len);
1773 STAT(tunnel_rx_packets);
1774 INC_STAT(tunnel_rx_bytes, len);
1775 if (len < 6)
1776 {
1777 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1778 STAT(tunnel_rx_errors);
1779 return;
1780 }
1781 if ((buf[1] & 0x0F) != 2)
1782 {
1783 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1784 STAT(tunnel_rx_errors);
1785 return;
1786 }
1787 if (*buf & 0x40)
1788 { // length
1789 l = ntohs(*(uint16_t *) p);
1790 p += 2;
1791 }
1792 t = ntohs(*(uint16_t *) p);
1793 p += 2;
1794 s = ntohs(*(uint16_t *) p);
1795 p += 2;
1796 if (s >= MAXSESSION)
1797 {
1798 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1799 STAT(tunnel_rx_errors);
1800 return;
1801 }
1802 if (t >= MAXTUNNEL)
1803 {
1804 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1805 STAT(tunnel_rx_errors);
1806 return;
1807 }
1808 if (*buf & 0x08)
1809 { // ns/nr
1810 ns = ntohs(*(uint16_t *) p);
1811 p += 2;
1812 nr = ntohs(*(uint16_t *) p);
1813 p += 2;
1814 }
1815 if (*buf & 0x02)
1816 { // offset
1817 uint16_t o = ntohs(*(uint16_t *) p);
1818 p += o + 2;
1819 }
1820 if ((p - buf) > l)
1821 {
1822 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1823 STAT(tunnel_rx_errors);
1824 return;
1825 }
1826 l -= (p - buf);
1827 if (*buf & 0x80)
1828 { // control
1829 uint16_t message = 0xFFFF; // message type
1830 uint8_t fatal = 0;
1831 uint8_t mandatory = 0;
1832 uint8_t authtype = 0; // proxy auth type
1833 uint16_t asession = 0; // assigned session
1834 uint32_t amagic = 0; // magic number
1835 uint8_t aflags = 0; // flags from last LCF
1836 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1837 char called[MAXTEL] = ""; // called number
1838 char calling[MAXTEL] = ""; // calling number
1839
1840 if (!config->cluster_iam_master)
1841 {
1842 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1843 return;
1844 }
1845
1846 // control messages must have bits 0x80|0x40|0x08
1847 // (type, length and sequence) set, and bits 0x02|0x01
1848 // (offset and priority) clear
1849 if ((*buf & 0xCB) != 0xC8)
1850 {
1851 LOG(1, s, t, "Bad control header %02X\n", *buf);
1852 STAT(tunnel_rx_errors);
1853 return;
1854 }
1855
1856 // check for duplicate tunnel open message
1857 if (!t && ns == 0)
1858 {
1859 int i;
1860
1861 //
1862 // Is this a duplicate of the first packet? (SCCRQ)
1863 //
1864 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1865 {
1866 if (tunnel[i].state != TUNNELOPENING ||
1867 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1868 tunnel[i].port != ntohs(addr->sin_port) )
1869 continue;
1870 t = i;
1871 LOG(3, s, t, "Duplicate SCCRQ?\n");
1872 break;
1873 }
1874 }
1875
1876 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1877 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1878
1879 // if no tunnel specified, assign one
1880 if (!t)
1881 {
1882 if (!(t = new_tunnel()))
1883 {
1884 LOG(1, 0, 0, "No more tunnels\n");
1885 STAT(tunnel_overflow);
1886 return;
1887 }
1888 tunnelclear(t);
1889 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1890 tunnel[t].port = ntohs(addr->sin_port);
1891 tunnel[t].window = 4; // default window
1892 STAT(tunnel_created);
1893 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1894 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1895 }
1896
1897 // If the 'ns' just received is not the 'nr' we're
1898 // expecting, just send an ack and drop it.
1899 //
1900 // if 'ns' is less, then we got a retransmitted packet.
1901 // if 'ns' is greater than missed a packet. Either way
1902 // we should ignore it.
1903 if (ns != tunnel[t].nr)
1904 {
1905 // is this the sequence we were expecting?
1906 STAT(tunnel_rx_errors);
1907 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1908 t, ns, tunnel[t].nr);
1909
1910 if (l) // Is this not a ZLB?
1911 controlnull(t);
1912 return;
1913 }
1914
1915 // This is used to time out old tunnels
1916 tunnel[t].lastrec = time_now;
1917
1918 // check sequence of this message
1919 {
1920 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1921 // some to clear maybe?
1922 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1923 {
1924 controlt *c = tunnel[t].controls;
1925 tunnel[t].controls = c->next;
1926 tunnel[t].controlc--;
1927 c->next = controlfree;
1928 controlfree = c;
1929 skip--;
1930 tunnel[t].try = 0; // we have progress
1931 }
1932
1933 // receiver advance (do here so quoted correctly in any sends below)
1934 if (l) tunnel[t].nr = (ns + 1);
1935 if (skip < 0) skip = 0;
1936 if (skip < tunnel[t].controlc)
1937 {
1938 // some control packets can now be sent that were previous stuck out of window
1939 int tosend = tunnel[t].window - skip;
1940 controlt *c = tunnel[t].controls;
1941 while (c && skip)
1942 {
1943 c = c->next;
1944 skip--;
1945 }
1946 while (c && tosend)
1947 {
1948 tunnel[t].try = 0; // first send
1949 tunnelsend(c->buf, c->length, t);
1950 c = c->next;
1951 tosend--;
1952 }
1953 }
1954 if (!tunnel[t].controlc)
1955 tunnel[t].retry = 0; // caught up
1956 }
1957 if (l)
1958 { // if not a null message
1959 int result = 0;
1960 int error = 0;
1961 char *msg = 0;
1962
1963 // process AVPs
1964 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1965 {
1966 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1967 uint8_t *b = p;
1968 uint8_t flags = *p;
1969 uint16_t mtype;
1970 if (n > l)
1971 {
1972 LOG(1, s, t, "Invalid length in AVP\n");
1973 STAT(tunnel_rx_errors);
1974 return;
1975 }
1976 p += n; // next
1977 l -= n;
1978 if (flags & 0x3C) // reserved bits, should be clear
1979 {
1980 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1981 fatal = flags;
1982 result = 2; // general error
1983 error = 3; // reserved field non-zero
1984 msg = 0;
1985 continue; // next
1986 }
1987 b += 2;
1988 if (*(uint16_t *) (b))
1989 {
1990 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1991 fatal = flags;
1992 result = 2; // general error
1993 error = 6; // generic vendor-specific error
1994 msg = "unsupported vendor-specific";
1995 continue; // next
1996 }
1997 b += 2;
1998 mtype = ntohs(*(uint16_t *) (b));
1999 b += 2;
2000 n -= 6;
2001
2002 if (flags & 0x40)
2003 {
2004 uint16_t orig_len;
2005
2006 // handle hidden AVPs
2007 if (!*config->l2tpsecret)
2008 {
2009 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2010 fatal = flags;
2011 result = 2; // general error
2012 error = 6; // generic vendor-specific error
2013 msg = "secret not specified";
2014 continue;
2015 }
2016 if (!session[s].random_vector_length)
2017 {
2018 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2019 fatal = flags;
2020 result = 2; // general error
2021 error = 6; // generic
2022 msg = "no random vector";
2023 continue;
2024 }
2025 if (n < 8)
2026 {
2027 LOG(2, s, t, "Short hidden AVP.\n");
2028 fatal = flags;
2029 result = 2; // general error
2030 error = 2; // length is wrong
2031 msg = 0;
2032 continue;
2033 }
2034
2035 // Unhide the AVP
2036 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2037
2038 orig_len = ntohs(*(uint16_t *) b);
2039 if (orig_len > n + 2)
2040 {
2041 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2042 orig_len, n);
2043
2044 fatal = flags;
2045 result = 2; // general error
2046 error = 2; // length is wrong
2047 msg = 0;
2048 continue;
2049 }
2050
2051 b += 2;
2052 n = orig_len;
2053 }
2054
2055 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2056 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2057
2058 switch (mtype)
2059 {
2060 case 0: // message type
2061 message = ntohs(*(uint16_t *) b);
2062 mandatory = flags & 0x80;
2063 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2064 break;
2065 case 1: // result code
2066 {
2067 uint16_t rescode = ntohs(*(uint16_t *) b);
2068 const char* resdesc = "(unknown)";
2069 if (message == 4)
2070 { /* StopCCN */
2071 resdesc = l2tp_stopccn_result_code(rescode);
2072 }
2073 else if (message == 14)
2074 { /* CDN */
2075 resdesc = l2tp_cdn_result_code(rescode);
2076 }
2077
2078 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2079 if (n >= 4)
2080 {
2081 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2082 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2083 }
2084 if (n > 4)
2085 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2086
2087 break;
2088 }
2089 break;
2090 case 2: // protocol version
2091 {
2092 version = ntohs(*(uint16_t *) (b));
2093 LOG(4, s, t, " Protocol version = %d\n", version);
2094 if (version && version != 0x0100)
2095 { // allow 0.0 and 1.0
2096 LOG(1, s, t, " Bad protocol version %04X\n", version);
2097 fatal = flags;
2098 result = 5; // unspported protocol version
2099 error = 0x0100; // supported version
2100 msg = 0;
2101 continue; // next
2102 }
2103 }
2104 break;
2105 case 3: // framing capabilities
2106 // LOG(4, s, t, "Framing capabilities\n");
2107 break;
2108 case 4: // bearer capabilities
2109 // LOG(4, s, t, "Bearer capabilities\n");
2110 break;
2111 case 5: // tie breaker
2112 // We never open tunnels, so we don't care about tie breakers
2113 // LOG(4, s, t, "Tie breaker\n");
2114 continue;
2115 case 6: // firmware revision
2116 // LOG(4, s, t, "Firmware revision\n");
2117 break;
2118 case 7: // host name
2119 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2120 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2121 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2122 // TBA - to send to RADIUS
2123 break;
2124 case 8: // vendor name
2125 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2126 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2127 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2128 break;
2129 case 9: // assigned tunnel
2130 tunnel[t].far = ntohs(*(uint16_t *) (b));
2131 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2132 break;
2133 case 10: // rx window
2134 tunnel[t].window = ntohs(*(uint16_t *) (b));
2135 if (!tunnel[t].window)
2136 tunnel[t].window = 1; // window of 0 is silly
2137 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2138 break;
2139 case 11: // Challenge
2140 {
2141 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2142 build_chap_response(b, 2, n, &chapresponse);
2143 }
2144 break;
2145 case 13: // Response
2146 // Why did they send a response? We never challenge.
2147 LOG(2, s, t, " received unexpected challenge response\n");
2148 break;
2149
2150 case 14: // assigned session
2151 asession = session[s].far = ntohs(*(uint16_t *) (b));
2152 LOG(4, s, t, " assigned session = %d\n", asession);
2153 break;
2154 case 15: // call serial number
2155 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2156 break;
2157 case 18: // bearer type
2158 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2159 // TBA - for RADIUS
2160 break;
2161 case 19: // framing type
2162 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2163 // TBA
2164 break;
2165 case 21: // called number
2166 memset(called, 0, sizeof(called));
2167 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2168 LOG(4, s, t, " Called <%s>\n", called);
2169 break;
2170 case 22: // calling number
2171 memset(calling, 0, sizeof(calling));
2172 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2173 LOG(4, s, t, " Calling <%s>\n", calling);
2174 break;
2175 case 23: // subtype
2176 break;
2177 case 24: // tx connect speed
2178 if (n == 4)
2179 {
2180 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2181 }
2182 else
2183 {
2184 // AS5300s send connect speed as a string
2185 char tmp[30];
2186 memset(tmp, 0, sizeof(tmp));
2187 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2188 session[s].tx_connect_speed = atol(tmp);
2189 }
2190 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2191 break;
2192 case 38: // rx connect speed
2193 if (n == 4)
2194 {
2195 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2196 }
2197 else
2198 {
2199 // AS5300s send connect speed as a string
2200 char tmp[30];
2201 memset(tmp, 0, sizeof(tmp));
2202 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2203 session[s].rx_connect_speed = atol(tmp);
2204 }
2205 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2206 break;
2207 case 25: // Physical Channel ID
2208 {
2209 uint32_t tmp = ntohl(*(uint32_t *) b);
2210 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2211 break;
2212 }
2213 case 29: // Proxy Authentication Type
2214 {
2215 uint16_t atype = ntohs(*(uint16_t *)b);
2216 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2217 if (atype == 2)
2218 authtype = AUTHCHAP;
2219 else if (atype == 3)
2220 authtype = AUTHPAP;
2221
2222 break;
2223 }
2224 case 30: // Proxy Authentication Name
2225 {
2226 char authname[64];
2227 memset(authname, 0, sizeof(authname));
2228 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2229 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2230 authname);
2231 break;
2232 }
2233 case 31: // Proxy Authentication Challenge
2234 {
2235 LOG(4, s, t, " Proxy Auth Challenge\n");
2236 break;
2237 }
2238 case 32: // Proxy Authentication ID
2239 {
2240 uint16_t authid = ntohs(*(uint16_t *)(b));
2241 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2242 break;
2243 }
2244 case 33: // Proxy Authentication Response
2245 LOG(4, s, t, " Proxy Auth Response\n");
2246 break;
2247 case 27: // last sent lcp
2248 { // find magic number
2249 uint8_t *p = b, *e = p + n;
2250 while (p + 1 < e && p[1] && p + p[1] <= e)
2251 {
2252 if (*p == 5 && p[1] == 6) // Magic-Number
2253 amagic = ntohl(*(uint32_t *) (p + 2));
2254 else if (*p == 3 && p[1] == 4 && *(uint16_t *) (p + 2) == htons(PPPPAP)) // Authentication-Protocol (PAP)
2255 authtype = AUTHPAP;
2256 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol (CHAP)
2257 authtype = AUTHCHAP;
2258 else if (*p == 7) // Protocol-Field-Compression
2259 aflags |= SESSIONPFC;
2260 else if (*p == 8) // Address-and-Control-Field-Compression
2261 aflags |= SESSIONACFC;
2262 p += p[1];
2263 }
2264 }
2265 break;
2266 case 28: // last recv lcp confreq
2267 break;
2268 case 26: // Initial Received LCP CONFREQ
2269 break;
2270 case 39: // seq required - we control it as an LNS anyway...
2271 break;
2272 case 36: // Random Vector
2273 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2274 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2275 if (n > sizeof(session[s].random_vector))
2276 n = sizeof(session[s].random_vector);
2277 memcpy(session[s].random_vector, b, n);
2278 session[s].random_vector_length = n;
2279 break;
2280 default:
2281 {
2282 static char e[] = "unknown AVP 0xXXXX";
2283 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2284 fatal = flags;
2285 result = 2; // general error
2286 error = 8; // unknown mandatory AVP
2287 sprintf((msg = e) + 14, "%04x", mtype);
2288 continue; // next
2289 }
2290 }
2291 }
2292 // process message
2293 if (fatal & 0x80)
2294 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2295 else
2296 switch (message)
2297 {
2298 case 1: // SCCRQ - Start Control Connection Request
2299 tunnel[t].state = TUNNELOPENING;
2300 if (main_quit != QUIT_SHUTDOWN)
2301 {
2302 controlt *c = controlnew(2); // sending SCCRP
2303 control16(c, 2, version, 1); // protocol version
2304 control32(c, 3, 3, 1); // framing
2305 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2306 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2307 control16(c, 9, t, 1); // assigned tunnel
2308 controladd(c, 0, t); // send the resply
2309 }
2310 else
2311 {
2312 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2313 }
2314 break;
2315 case 2: // SCCRP
2316 tunnel[t].state = TUNNELOPEN;
2317 break;
2318 case 3: // SCCN
2319 tunnel[t].state = TUNNELOPEN;
2320 controlnull(t); // ack
2321 break;
2322 case 4: // StopCCN
2323 controlnull(t); // ack
2324 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2325 break;
2326 case 6: // HELLO
2327 controlnull(t); // simply ACK
2328 break;
2329 case 7: // OCRQ
2330 // TBA
2331 break;
2332 case 8: // OCRO
2333 // TBA
2334 break;
2335 case 9: // OCCN
2336 // TBA
2337 break;
2338 case 10: // ICRQ
2339 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2340 {
2341 controlt *c = controlnew(11); // ICRP
2342
2343 s = sessionfree;
2344 sessionfree = session[s].next;
2345 memset(&session[s], 0, sizeof(session[s]));
2346
2347 if (s > config->cluster_highest_sessionid)
2348 config->cluster_highest_sessionid = s;
2349
2350 session[s].opened = time_now;
2351 session[s].tunnel = t;
2352 session[s].far = asession;
2353 session[s].last_packet = time_now;
2354 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2355 control16(c, 14, s, 1); // assigned session
2356 controladd(c, asession, t); // send the reply
2357
2358 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2359 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2360
2361 session[s].ppp.phase = Establish;
2362 session[s].ppp.lcp = Starting;
2363
2364 STAT(session_created);
2365 break;
2366 }
2367
2368 {
2369 controlt *c = controlnew(14); // CDN
2370 if (!sessionfree)
2371 {
2372 STAT(session_overflow);
2373 LOG(1, 0, t, "No free sessions\n");
2374 control16(c, 1, 4, 0); // temporary lack of resources
2375 }
2376 else
2377 control16(c, 1, 2, 7); // shutting down, try another
2378
2379 controladd(c, asession, t); // send the message
2380 }
2381 return;
2382 case 11: // ICRP
2383 // TBA
2384 break;
2385 case 12: // ICCN
2386 if (amagic == 0) amagic = time_now;
2387 session[s].magic = amagic; // set magic number
2388 session[s].l2tp_flags = aflags; // set flags received
2389 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
2390 controlnull(t); // ack
2391
2392 // proxy authentication type is not supported
2393 if (!(config->radius_authtypes & authtype))
2394 authtype = config->radius_authprefer;
2395
2396 // start LCP
2397 sendlcp(s, t, authtype);
2398 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2399 sess_local[s].lcp.conf_sent = 1;
2400 sess_local[s].lcp.nak_sent = 0;
2401 sess_local[s].lcp_authtype = authtype;
2402 session[s].ppp.lcp = RequestSent;
2403
2404 break;
2405 case 14: // CDN
2406 controlnull(t); // ack
2407 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2408 break;
2409 case 0xFFFF:
2410 LOG(1, s, t, "Missing message type\n");
2411 break;
2412 default:
2413 STAT(tunnel_rx_errors);
2414 if (mandatory)
2415 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2416 else
2417 LOG(1, s, t, "Unknown message type %d\n", message);
2418 break;
2419 }
2420 if (chapresponse) free(chapresponse);
2421 cluster_send_tunnel(t);
2422 }
2423 else
2424 {
2425 LOG(4, s, t, " Got a ZLB ack\n");
2426 }
2427 }
2428 else
2429 { // data
2430 uint16_t prot;
2431
2432 LOG_HEX(5, "Receive Tunnel Data", p, l);
2433 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2434 { // HDLC address header, discard
2435 p += 2;
2436 l -= 2;
2437 }
2438 if (l < 2)
2439 {
2440 LOG(1, s, t, "Short ppp length %d\n", l);
2441 STAT(tunnel_rx_errors);
2442 return;
2443 }
2444 if (*p & 1)
2445 {
2446 prot = *p++;
2447 l--;
2448 }
2449 else
2450 {
2451 prot = ntohs(*(uint16_t *) p);
2452 p += 2;
2453 l -= 2;
2454 }
2455
2456 if (s && !session[s].opened) // Is something wrong??
2457 {
2458 if (!config->cluster_iam_master)
2459 {
2460 // Pass it off to the master to deal with..
2461 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2462 return;
2463 }
2464
2465
2466 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2467 STAT(tunnel_rx_errors);
2468 return;
2469 }
2470
2471 if (prot == PPPPAP)
2472 {
2473 session[s].last_packet = time_now;
2474 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2475 processpap(s, t, p, l);
2476 }
2477 else if (prot == PPPCHAP)
2478 {
2479 session[s].last_packet = time_now;
2480 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2481 processchap(s, t, p, l);
2482 }
2483 else if (prot == PPPLCP)
2484 {
2485 session[s].last_packet = time_now;
2486 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2487 processlcp(s, t, p, l);
2488 }
2489 else if (prot == PPPIPCP)
2490 {
2491 session[s].last_packet = time_now;
2492 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2493 processipcp(s, t, p, l);
2494 }
2495 else if (prot == PPPIPV6CP)
2496 {
2497 session[s].last_packet = time_now;
2498 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2499 processipv6cp(s, t, p, l);
2500 }
2501 else if (prot == PPPCCP)
2502 {
2503 session[s].last_packet = time_now;
2504 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2505 processccp(s, t, p, l);
2506 }
2507 else if (prot == PPPIP)
2508 {
2509 if (session[s].die)
2510 {
2511 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2512 return; // closing session, PPP not processed
2513 }
2514
2515 session[s].last_packet = time_now;
2516 if (session[s].walled_garden && !config->cluster_iam_master)
2517 {
2518 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2519 return;
2520 }
2521
2522 processipin(s, t, p, l);
2523 }
2524 else if (prot == PPPIPV6)
2525 {
2526 if (!config->ipv6_prefix.s6_addr[0])
2527 {
2528 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2529 return;
2530 }
2531 if (session[s].die)
2532 {
2533 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2534 return; // closing session, PPP not processed
2535 }
2536
2537 session[s].last_packet = time_now;
2538 if (session[s].walled_garden && !config->cluster_iam_master)
2539 {
2540 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2541 return;
2542 }
2543
2544 processipv6in(s, t, p, l);
2545 }
2546 else
2547 {
2548 STAT(tunnel_rx_errors);
2549 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2550 }
2551 }
2552 }
2553
2554 // read and process packet on tun
2555 static void processtun(uint8_t * buf, int len)
2556 {
2557 LOG_HEX(5, "Receive TUN Data", buf, len);
2558 STAT(tun_rx_packets);
2559 INC_STAT(tun_rx_bytes, len);
2560
2561 CSTAT(processtun);
2562
2563 eth_rx_pkt++;
2564 eth_rx += len;
2565 if (len < 22)
2566 {
2567 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2568 STAT(tun_rx_errors);
2569 return;
2570 }
2571
2572 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2573 processipout(buf, len);
2574 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2575 && config->ipv6_prefix.s6_addr[0])
2576 processipv6out(buf, len);
2577
2578 // Else discard.
2579 }
2580
2581 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2582 // that we look at the whole of the tunnel, radius and session tables
2583 // every second
2584 static void regular_cleanups(double period)
2585 {
2586 // Next tunnel, radius and session to check for actions on.
2587 static tunnelidt t = 0;
2588 static int r = 0;
2589 static sessionidt s = 0;
2590
2591 int t_actions = 0;
2592 int r_actions = 0;
2593 int s_actions = 0;
2594
2595 int t_slice;
2596 int r_slice;
2597 int s_slice;
2598
2599 int i;
2600 int a;
2601
2602 // divide up tables into slices based on the last run
2603 t_slice = config->cluster_highest_tunnelid * period;
2604 r_slice = (MAXRADIUS - 1) * period;
2605 s_slice = config->cluster_highest_sessionid * period;
2606
2607 if (t_slice < 1)
2608 t_slice = 1;
2609 else if (t_slice > config->cluster_highest_tunnelid)
2610 t_slice = config->cluster_highest_tunnelid;
2611
2612 if (r_slice < 1)
2613 r_slice = 1;
2614 else if (r_slice > (MAXRADIUS - 1))
2615 r_slice = MAXRADIUS - 1;
2616
2617 if (s_slice < 1)
2618 s_slice = 1;
2619 else if (s_slice > config->cluster_highest_sessionid)
2620 s_slice = config->cluster_highest_sessionid;
2621
2622 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2623
2624 for (i = 0; i < t_slice; i++)
2625 {
2626 t++;
2627 if (t > config->cluster_highest_tunnelid)
2628 t = 1;
2629
2630 // check for expired tunnels
2631 if (tunnel[t].die && tunnel[t].die <= TIME)
2632 {
2633 STAT(tunnel_timeout);
2634 tunnelkill(t, "Expired");
2635 t_actions++;
2636 continue;
2637 }
2638 // check for message resend
2639 if (tunnel[t].retry && tunnel[t].controlc)
2640 {
2641 // resend pending messages as timeout on reply
2642 if (tunnel[t].retry <= TIME)
2643 {
2644 controlt *c = tunnel[t].controls;
2645 uint8_t w = tunnel[t].window;
2646 tunnel[t].try++; // another try
2647 if (tunnel[t].try > 5)
2648 tunnelkill(t, "Timeout on control message"); // game over
2649 else
2650 while (c && w--)
2651 {
2652 tunnelsend(c->buf, c->length, t);
2653 c = c->next;
2654 }
2655
2656 t_actions++;
2657 }
2658 }
2659 // Send hello
2660 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2661 {
2662 controlt *c = controlnew(6); // sending HELLO
2663 controladd(c, 0, t); // send the message
2664 LOG(3, 0, t, "Sending HELLO message\n");
2665 t_actions++;
2666 }
2667
2668 // Check for tunnel changes requested from the CLI
2669 if ((a = cli_tunnel_actions[t].action))
2670 {
2671 cli_tunnel_actions[t].action = 0;
2672 if (a & CLI_TUN_KILL)
2673 {
2674 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2675 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2676 t_actions++;
2677 }
2678 }
2679 }
2680
2681 for (i = 0; i < r_slice; i++)
2682 {
2683 r++;
2684 if (r >= MAXRADIUS)
2685 r = 1;
2686
2687 if (!radius[r].state)
2688 continue;
2689
2690 if (radius[r].retry <= TIME)
2691 {
2692 radiusretry(r);
2693 r_actions++;
2694 }
2695 }
2696
2697 for (i = 0; i < s_slice; i++)
2698 {
2699 s++;
2700 if (s > config->cluster_highest_sessionid)
2701 s = 1;
2702
2703 if (!session[s].opened) // Session isn't in use
2704 continue;
2705
2706 // check for expired sessions
2707 if (session[s].die)
2708 {
2709 if (session[s].die <= TIME)
2710 {
2711 sessionkill(s, "Expired");
2712 s_actions++;
2713 }
2714 continue;
2715 }
2716
2717 // PPP timeouts
2718 if (sess_local[s].lcp.restart <= time_now)
2719 {
2720 int next_state = session[s].ppp.lcp;
2721 switch (session[s].ppp.lcp)
2722 {
2723 case RequestSent:
2724 case AckReceived:
2725 next_state = RequestSent;
2726
2727 case AckSent:
2728 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2729 {
2730 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2731 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2732 sess_local[s].lcp.conf_sent++;
2733 sendlcp(s, t, sess_local[s].lcp_authtype);
2734 change_state(s, lcp, next_state);
2735 }
2736 else
2737 {
2738 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2739 STAT(session_timeout);
2740 }
2741
2742 s_actions++;
2743 }
2744
2745 if (session[s].die)
2746 continue;
2747 }
2748
2749 if (sess_local[s].ipcp.restart <= time_now)
2750 {
2751 int next_state = session[s].ppp.ipcp;
2752 switch (session[s].ppp.ipcp)
2753 {
2754 case RequestSent:
2755 case AckReceived:
2756 next_state = RequestSent;
2757
2758 case AckSent:
2759 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2760 {
2761 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2762 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2763 sess_local[s].ipcp.conf_sent++;
2764 sendipcp(s, t);
2765 change_state(s, ipcp, next_state);
2766 }
2767 else
2768 {
2769 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2770 STAT(session_timeout);
2771 }
2772
2773 s_actions++;
2774 }
2775
2776 if (session[s].die)
2777 continue;
2778 }
2779
2780 if (sess_local[s].ipv6cp.restart <= time_now)
2781 {
2782 int next_state = session[s].ppp.ipv6cp;
2783 switch (session[s].ppp.ipv6cp)
2784 {
2785 case RequestSent:
2786 case AckReceived:
2787 next_state = RequestSent;
2788
2789 case AckSent:
2790 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2791 {
2792 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2793 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2794 sess_local[s].ipv6cp.conf_sent++;
2795 sendipv6cp(s, t);
2796 change_state(s, ipv6cp, next_state);
2797 }
2798 else
2799 {
2800 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2801 change_state(s, ipv6cp, Stopped);
2802 }
2803
2804 s_actions++;
2805 }
2806 }
2807
2808 if (sess_local[s].ccp.restart <= time_now)
2809 {
2810 int next_state = session[s].ppp.ccp;
2811 switch (session[s].ppp.ccp)
2812 {
2813 case RequestSent:
2814 case AckReceived:
2815 next_state = RequestSent;
2816
2817 case AckSent:
2818 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2819 {
2820 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2821 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2822 sess_local[s].ccp.conf_sent++;
2823 sendccp(s, t);
2824 change_state(s, ccp, next_state);
2825 }
2826 else
2827 {
2828 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2829 change_state(s, ccp, Stopped);
2830 }
2831
2832 s_actions++;
2833 }
2834 }
2835
2836 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2837 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2838 {
2839 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2840 STAT(session_timeout);
2841 s_actions++;
2842 continue;
2843 }
2844
2845 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2846 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2847 {
2848 uint8_t b[MAXCONTROL] = {0};
2849
2850 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2851 if (!q) continue;
2852
2853 *q = EchoReq;
2854 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2855 *(uint16_t *)(q + 2) = htons(8); // Length
2856 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2857
2858 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2859 (int)(time_now - session[s].last_packet));
2860 tunnelsend(b, 24, session[s].tunnel); // send it
2861 s_actions++;
2862 }
2863
2864 // Check for actions requested from the CLI
2865 if ((a = cli_session_actions[s].action))
2866 {
2867 int send = 0;
2868
2869 cli_session_actions[s].action = 0;
2870 if (a & CLI_SESS_KILL)
2871 {
2872 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2873 sessionshutdown(s, "Requested by administrator.", 3, 0);
2874 a = 0; // dead, no need to check for other actions
2875 s_actions++;
2876 }
2877
2878 if (a & CLI_SESS_NOSNOOP)
2879 {
2880 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2881 session[s].snoop_ip = 0;
2882 session[s].snoop_port = 0;
2883 s_actions++;
2884 send++;
2885 }
2886 else if (a & CLI_SESS_SNOOP)
2887 {
2888 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2889 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2890 cli_session_actions[s].snoop_port);
2891
2892 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2893 session[s].snoop_port = cli_session_actions[s].snoop_port;
2894 s_actions++;
2895 send++;
2896 }
2897
2898 if (a & CLI_SESS_NOTHROTTLE)
2899 {
2900 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2901 throttle_session(s, 0, 0);
2902 s_actions++;
2903 send++;
2904 }
2905 else if (a & CLI_SESS_THROTTLE)
2906 {
2907 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2908 cli_session_actions[s].throttle_in,
2909 cli_session_actions[s].throttle_out);
2910
2911 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2912 s_actions++;
2913 send++;
2914 }
2915
2916 if (a & CLI_SESS_NOFILTER)
2917 {
2918 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2919 filter_session(s, 0, 0);
2920 s_actions++;
2921 send++;
2922 }
2923 else if (a & CLI_SESS_FILTER)
2924 {
2925 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2926 cli_session_actions[s].filter_in,
2927 cli_session_actions[s].filter_out);
2928
2929 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2930 s_actions++;
2931 send++;
2932 }
2933
2934 if (send)
2935 cluster_send_session(s);
2936 }
2937
2938 // RADIUS interim accounting
2939 if (config->radius_accounting && config->radius_interim > 0
2940 && session[s].ip && !session[s].walled_garden
2941 && !sess_local[s].radius // RADIUS already in progress
2942 && time_now - sess_local[s].last_interim >= config->radius_interim)
2943 {
2944 int rad = radiusnew(s);
2945 if (!rad)
2946 {
2947 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2948 STAT(radius_overflow);
2949 continue;
2950 }
2951
2952 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2953 session[s].user, session[s].unique_id);
2954
2955 radiussend(rad, RADIUSINTERIM);
2956 sess_local[s].last_interim = time_now;
2957 s_actions++;
2958 }
2959 }
2960
2961 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2962 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2963 }
2964
2965 //
2966 // Are we in the middle of a tunnel update, or radius
2967 // requests??
2968 //
2969 static int still_busy(void)
2970 {
2971 int i;
2972 static clockt last_talked = 0;
2973 static clockt start_busy_wait = 0;
2974
2975 if (!config->cluster_iam_master)
2976 {
2977 #ifdef BGP
2978 static time_t stopped_bgp = 0;
2979 if (bgp_configured)
2980 {
2981 if (!stopped_bgp)
2982 {
2983 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2984
2985 for (i = 0; i < BGP_NUM_PEERS; i++)
2986 if (bgp_peers[i].state == Established)
2987 bgp_stop(&bgp_peers[i]);
2988
2989 stopped_bgp = time_now;
2990
2991 // we don't want to become master
2992 cluster_send_ping(0);
2993
2994 return 1;
2995 }
2996
2997 if (time_now < (stopped_bgp + QUIT_DELAY))
2998 return 1;
2999 }
3000 #endif /* BGP */
3001
3002 return 0;
3003 }
3004
3005 if (main_quit == QUIT_SHUTDOWN)
3006 {
3007 static int dropped = 0;
3008 if (!dropped)
3009 {
3010 int i;
3011
3012 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3013 for (i = 1; i < MAXTUNNEL; i++)
3014 if (tunnel[i].ip || tunnel[i].state)
3015 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3016
3017 dropped = 1;
3018 }
3019 }
3020
3021 if (start_busy_wait == 0)
3022 start_busy_wait = TIME;
3023
3024 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3025 {
3026 if (!tunnel[i].controlc)
3027 continue;
3028
3029 if (last_talked != TIME)
3030 {
3031 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3032 last_talked = TIME;
3033 }
3034 return 1;
3035 }
3036
3037 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3038 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3039 {
3040 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3041 return 0;
3042 }
3043
3044 for (i = 1; i < MAXRADIUS; i++)
3045 {
3046 if (radius[i].state == RADIUSNULL)
3047 continue;
3048 if (radius[i].state == RADIUSWAIT)
3049 continue;
3050
3051 if (last_talked != TIME)
3052 {
3053 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3054 last_talked = TIME;
3055 }
3056 return 1;
3057 }
3058
3059 return 0;
3060 }
3061
3062 #ifdef HAVE_EPOLL
3063 # include <sys/epoll.h>
3064 #else
3065 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3066 # include "fake_epoll.h"
3067 #endif
3068
3069 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3070 #define BASE_FDS 6
3071
3072 // additional polled fds
3073 #ifdef BGP
3074 # define EXTRA_FDS BGP_NUM_PEERS
3075 #else
3076 # define EXTRA_FDS 0
3077 #endif
3078
3079 // main loop - gets packets on tun or udp and processes them
3080 static void mainloop(void)
3081 {
3082 int i;
3083 uint8_t buf[65536];
3084 clockt next_cluster_ping = 0; // send initial ping immediately
3085 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3086 int maxevent = sizeof(events)/sizeof(*events);
3087
3088 if ((epollfd = epoll_create(maxevent)) < 0)
3089 {
3090 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3091 exit(1);
3092 }
3093
3094 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3095 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3096
3097 /* setup our fds to poll for input */
3098 {
3099 static struct event_data d[BASE_FDS];
3100 struct epoll_event e;
3101
3102 e.events = EPOLLIN;
3103 i = 0;
3104
3105 d[i].type = FD_TYPE_CLI;
3106 e.data.ptr = &d[i++];
3107 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3108
3109 d[i].type = FD_TYPE_CLUSTER;
3110 e.data.ptr = &d[i++];
3111 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3112
3113 d[i].type = FD_TYPE_TUN;
3114 e.data.ptr = &d[i++];
3115 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3116
3117 d[i].type = FD_TYPE_UDP;
3118 e.data.ptr = &d[i++];
3119 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3120
3121 d[i].type = FD_TYPE_CONTROL;
3122 e.data.ptr = &d[i++];
3123 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3124
3125 d[i].type = FD_TYPE_DAE;
3126 e.data.ptr = &d[i++];
3127 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3128 }
3129
3130 #ifdef BGP
3131 signal(SIGPIPE, SIG_IGN);
3132 bgp_setup(config->as_number);
3133 if (config->bind_address)
3134 bgp_add_route(config->bind_address, 0xffffffff);
3135
3136 for (i = 0; i < BGP_NUM_PEERS; i++)
3137 {
3138 if (config->neighbour[i].name[0])
3139 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3140 config->neighbour[i].as, config->neighbour[i].keepalive,
3141 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3142 }
3143 #endif /* BGP */
3144
3145 while (!main_quit || still_busy())
3146 {
3147 int more = 0;
3148 int n;
3149
3150 if (config->reload_config)
3151 {
3152 // Update the config state based on config settings
3153 update_config();
3154 }
3155
3156 #ifdef BGP
3157 bgp_set_poll();
3158 #endif /* BGP */
3159
3160 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3161 STAT(select_called);
3162
3163 TIME = now(NULL);
3164 if (n < 0)
3165 {
3166 if (errno == EINTR ||
3167 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3168 continue;
3169
3170 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3171 break; // exit
3172 }
3173
3174 if (n)
3175 {
3176 struct sockaddr_in addr;
3177 socklen_t alen;
3178 int c, s;
3179 int udp_ready = 0;
3180 int tun_ready = 0;
3181 int cluster_ready = 0;
3182 int udp_pkts = 0;
3183 int tun_pkts = 0;
3184 int cluster_pkts = 0;
3185 #ifdef BGP
3186 uint32_t bgp_events[BGP_NUM_PEERS];
3187 memset(bgp_events, 0, sizeof(bgp_events));
3188 #endif /* BGP */
3189
3190 for (c = n, i = 0; i < c; i++)
3191 {
3192 struct event_data *d = events[i].data.ptr;
3193 switch (d->type)
3194 {
3195 case FD_TYPE_CLI: // CLI connections
3196 {
3197 int cli;
3198
3199 alen = sizeof(addr);
3200 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3201 {
3202 cli_do(cli);
3203 close(cli);
3204 }
3205 else
3206 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3207
3208 n--;
3209 break;
3210 }
3211
3212 // these are handled below, with multiple interleaved reads
3213 case FD_TYPE_CLUSTER: cluster_ready++; break;
3214 case FD_TYPE_TUN: tun_ready++; break;
3215 case FD_TYPE_UDP: udp_ready++; break;
3216
3217 case FD_TYPE_CONTROL: // nsctl commands
3218 alen = sizeof(addr);
3219 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3220 n--;
3221 break;
3222
3223 case FD_TYPE_DAE: // DAE requests
3224 alen = sizeof(addr);
3225 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3226 n--;
3227 break;
3228
3229 case FD_TYPE_RADIUS: // RADIUS response
3230 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3231 if (s >= 0 && config->cluster_iam_master)
3232 processrad(buf, s, d->index);
3233
3234 n--;
3235 break;
3236
3237 #ifdef BGP
3238 case FD_TYPE_BGP:
3239 bgp_events[d->index] = events[i].events;
3240 n--;
3241 break;
3242 #endif /* BGP */
3243
3244 default:
3245 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3246 }
3247 }
3248
3249 #ifdef BGP
3250 bgp_process(bgp_events);
3251 #endif /* BGP */
3252
3253 for (c = 0; n && c < config->multi_read_count; c++)
3254 {
3255 // L2TP
3256 if (udp_ready)
3257 {
3258 alen = sizeof(addr);
3259 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3260 {
3261 processudp(buf, s, &addr);
3262 udp_pkts++;
3263 }
3264 else
3265 {
3266 udp_ready = 0;
3267 n--;
3268 }
3269 }
3270
3271 // incoming IP
3272 if (tun_ready)
3273 {
3274 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3275 {
3276 processtun(buf, s);
3277 tun_pkts++;
3278 }
3279 else
3280 {
3281 tun_ready = 0;
3282 n--;
3283 }
3284 }
3285
3286 // cluster
3287 if (cluster_ready)
3288 {
3289 alen = sizeof(addr);
3290 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3291 {
3292 processcluster(buf, s, addr.sin_addr.s_addr);
3293 cluster_pkts++;
3294 }
3295 else
3296 {
3297 cluster_ready = 0;
3298 n--;
3299 }
3300 }
3301 }
3302
3303 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3304 STAT(multi_read_used);
3305
3306 if (c >= config->multi_read_count)
3307 {
3308 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3309 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3310
3311 STAT(multi_read_exceeded);
3312 more++;
3313 }
3314 }
3315
3316 // Runs on every machine (master and slaves).
3317 if (next_cluster_ping <= TIME)
3318 {
3319 // Check to see which of the cluster is still alive..
3320
3321 cluster_send_ping(basetime); // Only does anything if we're a slave
3322 cluster_check_master(); // ditto.
3323
3324 cluster_heartbeat(); // Only does anything if we're a master.
3325 cluster_check_slaves(); // ditto.
3326
3327 master_update_counts(); // If we're a slave, send our byte counters to our master.
3328
3329 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3330 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3331 else
3332 next_cluster_ping = TIME + config->cluster_hb_interval;
3333 }
3334
3335 if (!config->cluster_iam_master)
3336 continue;
3337
3338 // Run token bucket filtering queue..
3339 // Only run it every 1/10th of a second.
3340 {
3341 static clockt last_run = 0;
3342 if (last_run != TIME)
3343 {
3344 last_run = TIME;
3345 tbf_run_timer();
3346 }
3347 }
3348
3349 // Handle timeouts, retries etc.
3350 {
3351 static double last_clean = 0;
3352 double this_clean;
3353 double diff;
3354
3355 TIME = now(&this_clean);
3356 diff = this_clean - last_clean;
3357
3358 // Run during idle time (after we've handled
3359 // all incoming packets) or every 1/10th sec
3360 if (!more || diff > 0.1)
3361 {
3362 regular_cleanups(diff);
3363 last_clean = this_clean;
3364 }
3365 }
3366
3367 if (*config->accounting_dir)
3368 {
3369 static clockt next_acct = 0;
3370 static clockt next_shut_acct = 0;
3371
3372 if (next_acct <= TIME)
3373 {
3374 // Dump accounting data
3375 next_acct = TIME + ACCT_TIME;
3376 next_shut_acct = TIME + ACCT_SHUT_TIME;
3377 dump_acct_info(1);
3378 }
3379 else if (next_shut_acct <= TIME)
3380 {
3381 // Dump accounting data for shutdown sessions
3382 next_shut_acct = TIME + ACCT_SHUT_TIME;
3383 if (shut_acct_n)
3384 dump_acct_info(0);
3385 }
3386 }
3387 }
3388
3389 // Are we the master and shutting down??
3390 if (config->cluster_iam_master)
3391 cluster_heartbeat(); // Flush any queued changes..
3392
3393 // Ok. Notify everyone we're shutting down. If we're
3394 // the master, this will force an election.
3395 cluster_send_ping(0);
3396
3397 //
3398 // Important!!! We MUST not process any packets past this point!
3399 LOG(1, 0, 0, "Shutdown complete\n");
3400 }
3401
3402 static void stripdomain(char *host)
3403 {
3404 char *p;
3405
3406 if ((p = strchr(host, '.')))
3407 {
3408 char *domain = 0;
3409 char _domain[1024];
3410
3411 // strip off domain
3412 FILE *resolv = fopen("/etc/resolv.conf", "r");
3413 if (resolv)
3414 {
3415 char buf[1024];
3416 char *b;
3417
3418 while (fgets(buf, sizeof(buf), resolv))
3419 {
3420 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3421 continue;
3422
3423 if (!isspace(buf[6]))
3424 continue;
3425
3426 b = buf + 7;
3427 while (isspace(*b)) b++;
3428
3429 if (*b)
3430 {
3431 char *d = b;
3432 while (*b && !isspace(*b)) b++;
3433 *b = 0;
3434 if (buf[0] == 'd') // domain is canonical
3435 {
3436 domain = d;
3437 break;
3438 }
3439
3440 // first search line
3441 if (!domain)
3442 {
3443 // hold, may be subsequent domain line
3444 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3445 domain = _domain;
3446 }
3447 }
3448 }
3449
3450 fclose(resolv);
3451 }
3452
3453 if (domain)
3454 {
3455 int hl = strlen(host);
3456 int dl = strlen(domain);
3457 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3458 host[hl -dl - 1] = 0;
3459 }
3460 else
3461 {
3462 *p = 0; // everything after first dot
3463 }
3464 }
3465 }
3466
3467 // Init data structures
3468 static void initdata(int optdebug, char *optconfig)
3469 {
3470 int i;
3471
3472 if (!(config = shared_malloc(sizeof(configt))))
3473 {
3474 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3475 exit(1);
3476 }
3477
3478 memset(config, 0, sizeof(configt));
3479 time(&config->start_time);
3480 strncpy(config->config_file, optconfig, strlen(optconfig));
3481 config->debug = optdebug;
3482 config->num_tbfs = MAXTBFS;
3483 config->rl_rate = 28; // 28kbps
3484 config->cluster_master_min_adv = 1;
3485 config->ppp_restart_time = 3;
3486 config->ppp_max_configure = 10;
3487 config->ppp_max_failure = 5;
3488 strcpy(config->random_device, RANDOMDEVICE);
3489
3490 log_stream = stderr;
3491
3492 #ifdef RINGBUFFER
3493 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3494 {
3495 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3496 exit(1);
3497 }
3498 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3499 #endif
3500
3501 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3502 {
3503 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3504 exit(1);
3505 }
3506 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3507 {
3508 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3509 exit(1);
3510 }
3511 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3512 {
3513 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3514 exit(1);
3515 }
3516
3517 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3518 {
3519 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3520 exit(1);
3521 }
3522
3523 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3524 {
3525 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3526 exit(1);
3527 }
3528
3529 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3530 {
3531 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3532 exit(1);
3533 }
3534
3535 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3536 {
3537 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3538 exit(1);
3539 }
3540 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3541
3542 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3543 {
3544 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3545 exit(1);
3546 }
3547 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3548
3549 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3550 {
3551 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3552 exit(1);
3553 }
3554 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3555
3556 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3557 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3558 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3559 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3560
3561 // Put all the sessions on the free list marked as undefined.
3562 for (i = 1; i < MAXSESSION; i++)
3563 {
3564 session[i].next = i + 1;
3565 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3566 }
3567 session[MAXSESSION - 1].next = 0;
3568 sessionfree = 1;
3569
3570 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3571 for (i = 1; i < MAXTUNNEL; i++)
3572 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3573
3574 if (!*hostname)
3575 {
3576 // Grab my hostname unless it's been specified
3577 gethostname(hostname, sizeof(hostname));
3578 stripdomain(hostname);
3579 }
3580
3581 _statistics->start_time = _statistics->last_reset = time(NULL);
3582
3583 #ifdef BGP
3584 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3585 {
3586 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3587 exit(1);
3588 }
3589 #endif /* BGP */
3590 }
3591
3592 static int assign_ip_address(sessionidt s)
3593 {
3594 uint32_t i;
3595 int best = -1;
3596 time_t best_time = time_now;
3597 char *u = session[s].user;
3598 char reuse = 0;
3599
3600
3601 CSTAT(assign_ip_address);
3602
3603 for (i = 1; i < ip_pool_size; i++)
3604 {
3605 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3606 continue;
3607
3608 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3609 {
3610 best = i;
3611 reuse = 1;
3612 break;
3613 }
3614
3615 if (ip_address_pool[i].last < best_time)
3616 {
3617 best = i;
3618 if (!(best_time = ip_address_pool[i].last))
3619 break; // never used, grab this one
3620 }
3621 }
3622
3623 if (best < 0)
3624 {
3625 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3626 return 0;
3627 }
3628
3629 session[s].ip = ip_address_pool[best].address;
3630 session[s].ip_pool_index = best;
3631 ip_address_pool[best].assigned = 1;
3632 ip_address_pool[best].last = time_now;
3633 ip_address_pool[best].session = s;
3634 if (session[s].walled_garden)
3635 /* Don't track addresses of users in walled garden (note: this
3636 means that their address isn't "sticky" even if they get
3637 un-gardened). */
3638 ip_address_pool[best].user[0] = 0;
3639 else
3640 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3641
3642 STAT(ip_allocated);
3643 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3644 reuse ? "Reusing" : "Allocating", best);
3645
3646 return 1;
3647 }
3648
3649 static void free_ip_address(sessionidt s)
3650 {
3651 int i = session[s].ip_pool_index;
3652
3653
3654 CSTAT(free_ip_address);
3655
3656 if (!session[s].ip)
3657 return; // what the?
3658
3659 if (i < 0) // Is this actually part of the ip pool?
3660 i = 0;
3661
3662 STAT(ip_freed);
3663 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3664 session[s].ip = 0;
3665 ip_address_pool[i].assigned = 0;
3666 ip_address_pool[i].session = 0;
3667 ip_address_pool[i].last = time_now;
3668 }
3669
3670 //
3671 // Fsck the address pool against the session table.
3672 // Normally only called when we become a master.
3673 //
3674 // This isn't perfect: We aren't keep tracking of which
3675 // users used to have an IP address.
3676 //
3677 void rebuild_address_pool(void)
3678 {
3679 int i;
3680
3681 //
3682 // Zero the IP pool allocation, and build
3683 // a map from IP address to pool index.
3684 for (i = 1; i < MAXIPPOOL; ++i)
3685 {
3686 ip_address_pool[i].assigned = 0;
3687 ip_address_pool[i].session = 0;
3688 if (!ip_address_pool[i].address)
3689 continue;
3690
3691 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3692 }
3693
3694 for (i = 0; i < MAXSESSION; ++i)
3695 {
3696 int ipid;
3697 if (!(session[i].opened && session[i].ip))
3698 continue;
3699
3700 ipid = - lookup_ipmap(htonl(session[i].ip));
3701
3702 if (session[i].ip_pool_index < 0)
3703 {
3704 // Not allocated out of the pool.
3705 if (ipid < 1) // Not found in the pool either? good.
3706 continue;
3707
3708 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3709 i, fmtaddr(session[i].ip, 0), ipid);
3710
3711 // Fall through and process it as part of the pool.
3712 }
3713
3714
3715 if (ipid > MAXIPPOOL || ipid < 0)
3716 {
3717 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3718 ipid = -1;
3719 session[i].ip_pool_index = ipid;
3720 continue;
3721 }
3722
3723 ip_address_pool[ipid].assigned = 1;
3724 ip_address_pool[ipid].session = i;
3725 ip_address_pool[ipid].last = time_now;
3726 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3727 session[i].ip_pool_index = ipid;
3728 cache_ipmap(session[i].ip, i); // Fix the ip map.
3729 }
3730 }
3731
3732 //
3733 // Fix the address pool to match a changed session.
3734 // (usually when the master sends us an update).
3735 static void fix_address_pool(int sid)
3736 {
3737 int ipid;
3738
3739 ipid = session[sid].ip_pool_index;
3740
3741 if (ipid > ip_pool_size)
3742 return; // Ignore it. rebuild_address_pool will fix it up.
3743
3744 if (ip_address_pool[ipid].address != session[sid].ip)
3745 return; // Just ignore it. rebuild_address_pool will take care of it.
3746
3747 ip_address_pool[ipid].assigned = 1;
3748 ip_address_pool[ipid].session = sid;
3749 ip_address_pool[ipid].last = time_now;
3750 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3751 }
3752
3753 //
3754 // Add a block of addresses to the IP pool to hand out.
3755 //
3756 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3757 {
3758 int i;
3759 if (mask == 0)
3760 mask = 0xffffffff; // Host route only.
3761
3762 addr &= mask;
3763
3764 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3765 return ;
3766
3767 for (i = addr ;(i & mask) == addr; ++i)
3768 {
3769 if ((i & 0xff) == 0 || (i&0xff) == 255)
3770 continue; // Skip 0 and broadcast addresses.
3771
3772 ip_address_pool[ip_pool_size].address = i;
3773 ip_address_pool[ip_pool_size].assigned = 0;
3774 ++ip_pool_size;
3775 if (ip_pool_size >= MAXIPPOOL)
3776 {
3777 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3778 return;
3779 }
3780 }
3781 }
3782
3783 // Initialize the IP address pool
3784 static void initippool()
3785 {
3786 FILE *f;
3787 char *p;
3788 char buf[4096];
3789 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3790
3791 if (!(f = fopen(IPPOOLFILE, "r")))
3792 {
3793 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3794 exit(1);
3795 }
3796
3797 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3798 {
3799 char *pool = buf;
3800 buf[4095] = 0; // Force it to be zero terminated/
3801
3802 if (*buf == '#' || *buf == '\n')
3803 continue; // Skip comments / blank lines
3804 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3805 if ((p = (char *)strchr(buf, ':')))
3806 {
3807 in_addr_t src;
3808 *p = '\0';
3809 src = inet_addr(buf);
3810 if (src == INADDR_NONE)
3811 {
3812 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3813 exit(1);
3814 }
3815 // This entry is for a specific IP only
3816 if (src != config->bind_address)
3817 continue;
3818 *p = ':';
3819 pool = p+1;
3820 }
3821 if ((p = (char *)strchr(pool, '/')))
3822 {
3823 // It's a range
3824 int numbits = 0;
3825 in_addr_t start = 0, mask = 0;
3826
3827 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3828 *p++ = 0;
3829 if (!*p || !(numbits = atoi(p)))
3830 {
3831 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3832 continue;
3833 }
3834 start = ntohl(inet_addr(pool));
3835 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3836
3837 // Add a static route for this pool
3838 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3839 fmtaddr(htonl(start), 0), 32 + mask);
3840
3841 routeset(0, start, mask, 0, 1);
3842
3843 add_to_ip_pool(start, mask);
3844 }
3845 else
3846 {
3847 // It's a single ip address
3848 add_to_ip_pool(inet_addr(pool), 0);
3849 }
3850 }
3851 fclose(f);
3852 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3853 }
3854
3855 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3856 {
3857 struct sockaddr_in snoop_addr = {0};
3858 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3859 return;
3860
3861 snoop_addr.sin_family = AF_INET;
3862 snoop_addr.sin_addr.s_addr = destination;
3863 snoop_addr.sin_port = ntohs(port);
3864
3865 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3866 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3867 htons(snoop_addr.sin_port));
3868
3869 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3870 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3871
3872 STAT(packets_snooped);
3873 }
3874
3875 static int dump_session(FILE **f, sessiont *s)
3876 {
3877 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3878 return 1;
3879
3880 if (!*f)
3881 {
3882 char filename[1024];
3883 char timestr[64];
3884 time_t now = time(NULL);
3885
3886 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3887 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3888
3889 if (!(*f = fopen(filename, "w")))
3890 {
3891 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3892 return 0;
3893 }
3894
3895 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3896 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3897 "# host: %s\n"
3898 "# endpoint: %s\n"
3899 "# time: %ld\n"
3900 "# uptime: %ld\n"
3901 "# format: username ip qos uptxoctets downrxoctets\n",
3902 hostname,
3903 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3904 now,
3905 now - basetime);
3906 }
3907
3908 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3909 fprintf(*f, "%s %s %d %u %u\n",
3910 s->user, // username
3911 fmtaddr(htonl(s->ip), 0), // ip
3912 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3913 (uint32_t) s->cin_delta, // uptxoctets
3914 (uint32_t) s->cout_delta); // downrxoctets
3915
3916 s->cin_delta = s->cout_delta = 0;
3917
3918 return 1;
3919 }
3920
3921 static void dump_acct_info(int all)
3922 {
3923 int i;
3924 FILE *f = NULL;
3925
3926
3927 CSTAT(dump_acct_info);
3928
3929 if (shut_acct_n)
3930 {
3931 for (i = 0; i < shut_acct_n; i++)
3932 dump_session(&f, &shut_acct[i]);
3933
3934 shut_acct_n = 0;
3935 }
3936
3937 if (all)
3938 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3939 dump_session(&f, &session[i]);
3940
3941 if (f)
3942 fclose(f);
3943 }
3944
3945 // Main program
3946 int main(int argc, char *argv[])
3947 {
3948 int i;
3949 int optdebug = 0;
3950 char *optconfig = CONFIGFILE;
3951
3952 time(&basetime); // start clock
3953
3954 // scan args
3955 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3956 {
3957 switch (i)
3958 {
3959 case 'd':
3960 if (fork()) exit(0);
3961 setsid();
3962 freopen("/dev/null", "r", stdin);
3963 freopen("/dev/null", "w", stdout);
3964 freopen("/dev/null", "w", stderr);
3965 break;
3966 case 'v':
3967 optdebug++;
3968 break;
3969 case 'c':
3970 optconfig = optarg;
3971 break;
3972 case 'h':
3973 snprintf(hostname, sizeof(hostname), "%s", optarg);
3974 break;
3975 default:
3976 printf("Args are:\n"
3977 "\t-d\t\tDetach from terminal\n"
3978 "\t-c <file>\tConfig file\n"
3979 "\t-h <hostname>\tForce hostname\n"
3980 "\t-v\t\tDebug\n");
3981
3982 return (0);
3983 break;
3984 }
3985 }
3986
3987 // Start the timer routine off
3988 time(&time_now);
3989 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3990 signal(SIGALRM, sigalrm_handler);
3991 siginterrupt(SIGALRM, 0);
3992
3993 initplugins();
3994 initdata(optdebug, optconfig);
3995
3996 init_cli(hostname);
3997 read_config_file();
3998 init_tbf(config->num_tbfs);
3999
4000 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4001 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4002 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4003 {
4004 struct rlimit rlim;
4005 rlim.rlim_cur = RLIM_INFINITY;
4006 rlim.rlim_max = RLIM_INFINITY;
4007 // Remove the maximum core size
4008 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4009 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4010
4011 // Make core dumps go to /tmp
4012 chdir("/tmp");
4013 }
4014
4015 if (config->scheduler_fifo)
4016 {
4017 int ret;
4018 struct sched_param params = {0};
4019 params.sched_priority = 1;
4020
4021 if (get_nprocs() < 2)
4022 {
4023 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4024 config->scheduler_fifo = 0;
4025 }
4026 else
4027 {
4028 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4029 {
4030 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4031 }
4032 else
4033 {
4034 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4035 config->scheduler_fifo = 0;
4036 }
4037 }
4038 }
4039
4040 /* Set up the cluster communications port. */
4041 if (cluster_init() < 0)
4042 exit(1);
4043
4044 inittun();
4045 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4046
4047 initudp();
4048 initrad();
4049 initippool();
4050
4051 // seed prng
4052 {
4053 unsigned seed = time_now ^ getpid();
4054 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4055 srand(seed);
4056 }
4057
4058 signal(SIGHUP, sighup_handler);
4059 signal(SIGCHLD, sigchild_handler);
4060 signal(SIGTERM, shutdown_handler);
4061 signal(SIGINT, shutdown_handler);
4062 signal(SIGQUIT, shutdown_handler);
4063
4064 // Prevent us from getting paged out
4065 if (config->lock_pages)
4066 {
4067 if (!mlockall(MCL_CURRENT))
4068 LOG(1, 0, 0, "Locking pages into memory\n");
4069 else
4070 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4071 }
4072
4073 alarm(1);
4074
4075 // Drop privileges here
4076 if (config->target_uid > 0 && geteuid() == 0)
4077 setuid(config->target_uid);
4078
4079 mainloop();
4080
4081 /* remove plugins (so cleanup code gets run) */
4082 plugins_done();
4083
4084 // Remove the PID file if we wrote it
4085 if (config->wrote_pid && *config->pid_file == '/')
4086 unlink(config->pid_file);
4087
4088 /* kill CLI children */
4089 signal(SIGTERM, SIG_IGN);
4090 kill(0, SIGTERM);
4091 return 0;
4092 }
4093
4094 static void sighup_handler(int sig)
4095 {
4096 if (log_stream)
4097 {
4098 if (log_stream != stderr)
4099 fclose(log_stream);
4100
4101 log_stream = NULL;
4102 }
4103
4104 read_config_file();
4105 }
4106
4107 static void sigalrm_handler(int sig)
4108 {
4109 // Log current traffic stats
4110
4111 snprintf(config->bandwidth, sizeof(config->bandwidth),
4112 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4113 (udp_rx / 1024.0 / 1024.0 * 8),
4114 (eth_tx / 1024.0 / 1024.0 * 8),
4115 (eth_rx / 1024.0 / 1024.0 * 8),
4116 (udp_tx / 1024.0 / 1024.0 * 8),
4117 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4118 udp_rx_pkt, eth_rx_pkt);
4119
4120 udp_tx = udp_rx = 0;
4121 udp_rx_pkt = eth_rx_pkt = 0;
4122 eth_tx = eth_rx = 0;
4123
4124 if (config->dump_speed)
4125 printf("%s\n", config->bandwidth);
4126
4127 // Update the internal time counter
4128 time(&time_now);
4129 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4130 alarm(1);
4131
4132 {
4133 // Run timer hooks
4134 struct param_timer p = { time_now };
4135 run_plugins(PLUGIN_TIMER, &p);
4136 }
4137
4138 }
4139
4140 static void shutdown_handler(int sig)
4141 {
4142 LOG(1, 0, 0, "Shutting down\n");
4143 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4144 }
4145
4146 static void sigchild_handler(int sig)
4147 {
4148 while (waitpid(-1, NULL, WNOHANG) > 0)
4149 ;
4150 }
4151
4152 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4153 {
4154 MD5_CTX ctx;
4155 *challenge_response = NULL;
4156
4157 if (!*config->l2tpsecret)
4158 {
4159 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4160 return;
4161 }
4162
4163 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4164
4165 *challenge_response = calloc(17, 1);
4166
4167 MD5_Init(&ctx);
4168 MD5_Update(&ctx, &id, 1);
4169 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4170 MD5_Update(&ctx, challenge, challenge_length);
4171 MD5_Final(*challenge_response, &ctx);
4172
4173 return;
4174 }
4175
4176 static int facility_value(char *name)
4177 {
4178 int i;
4179 for (i = 0; facilitynames[i].c_name; i++)
4180 {
4181 if (strcmp(facilitynames[i].c_name, name) == 0)
4182 return facilitynames[i].c_val;
4183 }
4184 return 0;
4185 }
4186
4187 static void update_config()
4188 {
4189 int i;
4190 char *p;
4191 static int timeout = 0;
4192 static int interval = 0;
4193
4194 // Update logging
4195 closelog();
4196 syslog_log = 0;
4197 if (log_stream)
4198 {
4199 if (log_stream != stderr)
4200 fclose(log_stream);
4201
4202 log_stream = NULL;
4203 }
4204
4205 if (*config->log_filename)
4206 {
4207 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4208 {
4209 char *p = config->log_filename + 7;
4210 if (*p)
4211 {
4212 openlog("l2tpns", LOG_PID, facility_value(p));
4213 syslog_log = 1;
4214 }
4215 }
4216 else if (strchr(config->log_filename, '/') == config->log_filename)
4217 {
4218 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4219 {
4220 fseek(log_stream, 0, SEEK_END);
4221 setbuf(log_stream, NULL);
4222 }
4223 else
4224 {
4225 log_stream = stderr;
4226 setbuf(log_stream, NULL);
4227 }
4228 }
4229 }
4230 else
4231 {
4232 log_stream = stderr;
4233 setbuf(log_stream, NULL);
4234 }
4235
4236 // Update radius
4237 config->numradiusservers = 0;
4238 for (i = 0; i < MAXRADSERVER; i++)
4239 if (config->radiusserver[i])
4240 {
4241 config->numradiusservers++;
4242 // Set radius port: if not set, take the port from the
4243 // first radius server. For the first radius server,
4244 // take the #defined default value from l2tpns.h
4245
4246 // test twice, In case someone works with
4247 // a secondary radius server without defining
4248 // a primary one, this will work even then.
4249 if (i > 0 && !config->radiusport[i])
4250 config->radiusport[i] = config->radiusport[i-1];
4251 if (!config->radiusport[i])
4252 config->radiusport[i] = RADPORT;
4253 }
4254
4255 if (!config->numradiusservers)
4256 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4257
4258 // parse radius_authtypes_s
4259 config->radius_authtypes = config->radius_authprefer = 0;
4260 p = config->radius_authtypes_s;
4261 while (p && *p)
4262 {
4263 char *s = strpbrk(p, " \t,");
4264 int type = 0;
4265
4266 if (s)
4267 {
4268 *s++ = 0;
4269 while (*s == ' ' || *s == '\t')
4270 s++;
4271
4272 if (!*s)
4273 s = 0;
4274 }
4275
4276 if (!strncasecmp("chap", p, strlen(p)))
4277 type = AUTHCHAP;
4278 else if (!strncasecmp("pap", p, strlen(p)))
4279 type = AUTHPAP;
4280 else
4281 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4282
4283 config->radius_authtypes |= type;
4284 if (!config->radius_authprefer)
4285 config->radius_authprefer = type;
4286
4287 p = s;
4288 }
4289
4290 if (!config->radius_authtypes)
4291 {
4292 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4293 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4294 }
4295
4296 // normalise radius_authtypes_s
4297 if (config->radius_authprefer == AUTHPAP)
4298 {
4299 strcpy(config->radius_authtypes_s, "pap");
4300 if (config->radius_authtypes & AUTHCHAP)
4301 strcat(config->radius_authtypes_s, ", chap");
4302 }
4303 else
4304 {
4305 strcpy(config->radius_authtypes_s, "chap");
4306 if (config->radius_authtypes & AUTHPAP)
4307 strcat(config->radius_authtypes_s, ", pap");
4308 }
4309
4310 if (!config->radius_dae_port)
4311 config->radius_dae_port = DAEPORT;
4312
4313 // re-initialise the random number source
4314 initrandom(config->random_device);
4315
4316 // Update plugins
4317 for (i = 0; i < MAXPLUGINS; i++)
4318 {
4319 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4320 continue;
4321
4322 if (*config->plugins[i])
4323 {
4324 // Plugin added
4325 add_plugin(config->plugins[i]);
4326 }
4327 else if (*config->old_plugins[i])
4328 {
4329 // Plugin removed
4330 remove_plugin(config->old_plugins[i]);
4331 }
4332 }
4333
4334 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4335 if (!config->multi_read_count) config->multi_read_count = 10;
4336 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4337 if (!*config->cluster_interface)
4338 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4339
4340 if (!config->cluster_hb_interval)
4341 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4342
4343 if (!config->cluster_hb_timeout)
4344 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4345
4346 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4347 {
4348 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4349 // late, ensure we're sufficiently larger than that
4350 int t = 4 * config->cluster_hb_interval + 11;
4351
4352 if (config->cluster_hb_timeout < t)
4353 {
4354 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4355 config->cluster_hb_timeout = t;
4356 }
4357
4358 // Push timing changes to the slaves immediately if we're the master
4359 if (config->cluster_iam_master)
4360 cluster_heartbeat();
4361
4362 interval = config->cluster_hb_interval;
4363 timeout = config->cluster_hb_timeout;
4364 }
4365
4366 // Write PID file
4367 if (*config->pid_file == '/' && !config->wrote_pid)
4368 {
4369 FILE *f;
4370 if ((f = fopen(config->pid_file, "w")))
4371 {
4372 fprintf(f, "%d\n", getpid());
4373 fclose(f);
4374 config->wrote_pid = 1;
4375 }
4376 else
4377 {
4378 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4379 }
4380 }
4381
4382 config->reload_config = 0;
4383 }
4384
4385 static void read_config_file()
4386 {
4387 FILE *f;
4388
4389 if (!config->config_file) return;
4390 if (!(f = fopen(config->config_file, "r")))
4391 {
4392 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4393 return;
4394 }
4395
4396 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4397 cli_do_file(f);
4398 LOG(3, 0, 0, "Done reading config file\n");
4399 fclose(f);
4400 update_config();
4401 }
4402
4403 int sessionsetup(sessionidt s, tunnelidt t)
4404 {
4405 // A session now exists, set it up
4406 in_addr_t ip;
4407 char *user;
4408 sessionidt i;
4409 int r;
4410
4411 CSTAT(sessionsetup);
4412
4413 LOG(3, s, t, "Doing session setup for session\n");
4414
4415 if (!session[s].ip)
4416 {
4417 assign_ip_address(s);
4418 if (!session[s].ip)
4419 {
4420 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4421 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4422 return 0;
4423 }
4424 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4425 fmtaddr(htonl(session[s].ip), 0));
4426 }
4427
4428
4429 // Make sure this is right
4430 session[s].tunnel = t;
4431
4432 // zap old sessions with same IP and/or username
4433 // Don't kill gardened sessions - doing so leads to a DoS
4434 // from someone who doesn't need to know the password
4435 {
4436 ip = session[s].ip;
4437 user = session[s].user;
4438 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4439 {
4440 if (i == s) continue;
4441 if (!session[s].opened) continue;
4442 if (ip == session[i].ip)
4443 {
4444 sessionkill(i, "Duplicate IP address");
4445 continue;
4446 }
4447
4448 if (config->allow_duplicate_users) continue;
4449 if (session[s].walled_garden || session[i].walled_garden) continue;
4450 if (!strcasecmp(user, session[i].user))
4451 sessionkill(i, "Duplicate session for users");
4452 }
4453 }
4454
4455 {
4456 int routed = 0;
4457
4458 // Add the route for this session.
4459 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4460 {
4461 if ((session[s].ip & session[s].route[r].mask) ==
4462 (session[s].route[r].ip & session[s].route[r].mask))
4463 routed++;
4464
4465 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4466 }
4467
4468 // Static IPs need to be routed if not already
4469 // convered by a Framed-Route. Anything else is part
4470 // of the IP address pool and is already routed, it
4471 // just needs to be added to the IP cache.
4472 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4473 if (session[s].ip_pool_index == -1) // static ip
4474 {
4475 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4476 }
4477 else
4478 cache_ipmap(session[s].ip, s);
4479 }
4480
4481 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4482 lcp_open(s, t); // transition to Network phase and send initial IPCP
4483
4484 // Run the plugin's against this new session.
4485 {
4486 struct param_new_session data = { &tunnel[t], &session[s] };
4487 run_plugins(PLUGIN_NEW_SESSION, &data);
4488 }
4489
4490 // Allocate TBFs if throttled
4491 if (session[s].throttle_in || session[s].throttle_out)
4492 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4493
4494 session[s].last_packet = time_now;
4495
4496 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4497 fmtaddr(htonl(session[s].ip), 0),
4498 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4499
4500 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4501
4502 return 1; // RADIUS OK and IP allocated, done...
4503 }
4504
4505 //
4506 // This session just got dropped on us by the master or something.
4507 // Make sure our tables up up to date...
4508 //
4509 int load_session(sessionidt s, sessiont *new)
4510 {
4511 int i;
4512 int newip = 0;
4513
4514 // Sanity checks.
4515 if (new->ip_pool_index >= MAXIPPOOL ||
4516 new->tunnel >= MAXTUNNEL)
4517 {
4518 LOG(0, s, 0, "Strange session update received!\n");
4519 // FIXME! What to do here?
4520 return 0;
4521 }
4522
4523 //
4524 // Ok. All sanity checks passed. Now we're committed to
4525 // loading the new session.
4526 //
4527
4528 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4529
4530 // See if routes/ip cache need updating
4531 if (new->ip != session[s].ip)
4532 newip++;
4533
4534 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4535 if (new->route[i].ip != session[s].route[i].ip ||
4536 new->route[i].mask != session[s].route[i].mask)
4537 newip++;
4538
4539 // needs update
4540 if (newip)
4541 {
4542 int routed = 0;
4543
4544 // remove old routes...
4545 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4546 {
4547 if ((session[s].ip & session[s].route[i].mask) ==
4548 (session[s].route[i].ip & session[s].route[i].mask))
4549 routed++;
4550
4551 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4552 }
4553
4554 // ...ip
4555 if (session[s].ip)
4556 {
4557 if (session[s].ip_pool_index == -1) // static IP
4558 {
4559 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4560 }
4561 else // It's part of the IP pool, remove it manually.
4562 uncache_ipmap(session[s].ip);
4563 }
4564
4565 routed = 0;
4566
4567 // add new routes...
4568 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4569 {
4570 if ((new->ip & new->route[i].mask) ==
4571 (new->route[i].ip & new->route[i].mask))
4572 routed++;
4573
4574 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4575 }
4576
4577 // ...ip
4578 if (new->ip)
4579 {
4580 // If there's a new one, add it.
4581 if (new->ip_pool_index == -1)
4582 {
4583 if (!routed) routeset(s, new->ip, 0, 0, 1);
4584 }
4585 else
4586 cache_ipmap(new->ip, s);
4587 }
4588 }
4589
4590 // check v6 routing
4591 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4592 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4593
4594 // check filters
4595 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4596 {
4597 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4598 new->filter_in = 0;
4599 }
4600
4601 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4602 {
4603 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4604 new->filter_out = 0;
4605 }
4606
4607 if (new->filter_in != session[s].filter_in)
4608 {
4609 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4610 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4611 }
4612
4613 if (new->filter_out != session[s].filter_out)
4614 {
4615 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4616 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4617 }
4618
4619 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4620 // for walking the sessions to forward byte counts to the master.
4621 config->cluster_highest_sessionid = s;
4622
4623 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4624
4625 // Do fixups into address pool.
4626 if (new->ip_pool_index != -1)
4627 fix_address_pool(s);
4628
4629 return 1;
4630 }
4631
4632 static void initplugins()
4633 {
4634 int i;
4635
4636 loaded_plugins = ll_init();
4637 // Initialize the plugins to nothing
4638 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4639 plugins[i] = ll_init();
4640 }
4641
4642 static void *open_plugin(char *plugin_name, int load)
4643 {
4644 char path[256] = "";
4645
4646 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4647 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4648 return dlopen(path, RTLD_NOW);
4649 }
4650
4651 // plugin callback to get a config value
4652 static void *getconfig(char *key, enum config_typet type)
4653 {
4654 int i;
4655
4656 for (i = 0; config_values[i].key; i++)
4657 {
4658 if (!strcmp(config_values[i].key, key))
4659 {
4660 if (config_values[i].type == type)
4661 return ((void *) config) + config_values[i].offset;
4662
4663 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4664 key, type, config_values[i].type);
4665
4666 return 0;
4667 }
4668 }
4669
4670 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4671 return 0;
4672 }
4673
4674 static int add_plugin(char *plugin_name)
4675 {
4676 static struct pluginfuncs funcs = {
4677 _log,
4678 _log_hex,
4679 fmtaddr,
4680 sessionbyuser,
4681 sessiontbysessionidt,
4682 sessionidtbysessiont,
4683 radiusnew,
4684 radiussend,
4685 getconfig,
4686 sessionshutdown,
4687 sessionkill,
4688 throttle_session,
4689 cluster_send_session,
4690 };
4691
4692 void *p = open_plugin(plugin_name, 1);
4693 int (*initfunc)(struct pluginfuncs *);
4694 int i;
4695
4696 if (!p)
4697 {
4698 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4699 return -1;
4700 }
4701
4702 if (ll_contains(loaded_plugins, p))
4703 {
4704 dlclose(p);
4705 return 0; // already loaded
4706 }
4707
4708 {
4709 int *v = dlsym(p, "plugin_api_version");
4710 if (!v || *v != PLUGIN_API_VERSION)
4711 {
4712 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4713 dlclose(p);
4714 return -1;
4715 }
4716 }
4717
4718 if ((initfunc = dlsym(p, "plugin_init")))
4719 {
4720 if (!initfunc(&funcs))
4721 {
4722 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4723 dlclose(p);
4724 return -1;
4725 }
4726 }
4727
4728 ll_push(loaded_plugins, p);
4729
4730 for (i = 0; i < max_plugin_functions; i++)
4731 {
4732 void *x;
4733 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4734 {
4735 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4736 ll_push(plugins[i], x);
4737 }
4738 }
4739
4740 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4741 return 1;
4742 }
4743
4744 static void run_plugin_done(void *plugin)
4745 {
4746 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4747
4748 if (donefunc)
4749 donefunc();
4750 }
4751
4752 static int remove_plugin(char *plugin_name)
4753 {
4754 void *p = open_plugin(plugin_name, 0);
4755 int loaded = 0;
4756
4757 if (!p)
4758 return -1;
4759
4760 if (ll_contains(loaded_plugins, p))
4761 {
4762 int i;
4763 for (i = 0; i < max_plugin_functions; i++)
4764 {
4765 void *x;
4766 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4767 ll_delete(plugins[i], x);
4768 }
4769
4770 ll_delete(loaded_plugins, p);
4771 run_plugin_done(p);
4772 loaded = 1;
4773 }
4774
4775 dlclose(p);
4776 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4777 return loaded;
4778 }
4779
4780 int run_plugins(int plugin_type, void *data)
4781 {
4782 int (*func)(void *data);
4783
4784 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4785 return PLUGIN_RET_ERROR;
4786
4787 ll_reset(plugins[plugin_type]);
4788 while ((func = ll_next(plugins[plugin_type])))
4789 {
4790 int r = func(data);
4791
4792 if (r != PLUGIN_RET_OK)
4793 return r; // stop here
4794 }
4795
4796 return PLUGIN_RET_OK;
4797 }
4798
4799 static void plugins_done()
4800 {
4801 void *p;
4802
4803 ll_reset(loaded_plugins);
4804 while ((p = ll_next(loaded_plugins)))
4805 run_plugin_done(p);
4806 }
4807
4808 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4809 {
4810 struct nsctl request;
4811 struct nsctl response;
4812 int type = unpack_control(&request, buf, len);
4813 int r;
4814 void *p;
4815
4816 if (log_stream && config->debug >= 4)
4817 {
4818 if (type < 0)
4819 {
4820 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4821 fmtaddr(addr->sin_addr.s_addr, 0), type);
4822 }
4823 else
4824 {
4825 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4826 dump_control(&request, log_stream);
4827 }
4828 }
4829
4830 switch (type)
4831 {
4832 case NSCTL_REQ_LOAD:
4833 if (request.argc != 1)
4834 {
4835 response.type = NSCTL_RES_ERR;
4836 response.argc = 1;
4837 response.argv[0] = "name of plugin required";
4838 }
4839 else if ((r = add_plugin(request.argv[0])) < 1)
4840 {
4841 response.type = NSCTL_RES_ERR;
4842 response.argc = 1;
4843 response.argv[0] = !r
4844 ? "plugin already loaded"
4845 : "error loading plugin";
4846 }
4847 else
4848 {
4849 response.type = NSCTL_RES_OK;
4850 response.argc = 0;
4851 }
4852
4853 break;
4854
4855 case NSCTL_REQ_UNLOAD:
4856 if (request.argc != 1)
4857 {
4858 response.type = NSCTL_RES_ERR;
4859 response.argc = 1;
4860 response.argv[0] = "name of plugin required";
4861 }
4862 else if ((r = remove_plugin(request.argv[0])) < 1)
4863 {
4864 response.type = NSCTL_RES_ERR;
4865 response.argc = 1;
4866 response.argv[0] = !r
4867 ? "plugin not loaded"
4868 : "plugin not found";
4869 }
4870 else
4871 {
4872 response.type = NSCTL_RES_OK;
4873 response.argc = 0;
4874 }
4875
4876 break;
4877
4878 case NSCTL_REQ_HELP:
4879 response.type = NSCTL_RES_OK;
4880 response.argc = 0;
4881
4882 ll_reset(loaded_plugins);
4883 while ((p = ll_next(loaded_plugins)))
4884 {
4885 char **help = dlsym(p, "plugin_control_help");
4886 while (response.argc < 0xff && help && *help)
4887 response.argv[response.argc++] = *help++;
4888 }
4889
4890 break;
4891
4892 case NSCTL_REQ_CONTROL:
4893 {
4894 struct param_control param = {
4895 config->cluster_iam_master,
4896 request.argc,
4897 request.argv,
4898 0,
4899 NULL,
4900 };
4901
4902 int r = run_plugins(PLUGIN_CONTROL, &param);
4903
4904 if (r == PLUGIN_RET_ERROR)
4905 {
4906 response.type = NSCTL_RES_ERR;
4907 response.argc = 1;
4908 response.argv[0] = param.additional
4909 ? param.additional
4910 : "error returned by plugin";
4911 }
4912 else if (r == PLUGIN_RET_NOTMASTER)
4913 {
4914 static char msg[] = "must be run on master: 000.000.000.000";
4915
4916 response.type = NSCTL_RES_ERR;
4917 response.argc = 1;
4918 if (config->cluster_master_address)
4919 {
4920 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4921 response.argv[0] = msg;
4922 }
4923 else
4924 {
4925 response.argv[0] = "must be run on master: none elected";
4926 }
4927 }
4928 else if (!(param.response & NSCTL_RESPONSE))
4929 {
4930 response.type = NSCTL_RES_ERR;
4931 response.argc = 1;
4932 response.argv[0] = param.response
4933 ? "unrecognised response value from plugin"
4934 : "unhandled action";
4935 }
4936 else
4937 {
4938 response.type = param.response;
4939 response.argc = 0;
4940 if (param.additional)
4941 {
4942 response.argc = 1;
4943 response.argv[0] = param.additional;
4944 }
4945 }
4946 }
4947
4948 break;
4949
4950 default:
4951 response.type = NSCTL_RES_ERR;
4952 response.argc = 1;
4953 response.argv[0] = "error unpacking control packet";
4954 }
4955
4956 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4957 if (!buf)
4958 {
4959 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4960 return;
4961 }
4962
4963 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4964 if (r > 0)
4965 {
4966 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4967 if (log_stream && config->debug >= 4)
4968 {
4969 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4970 dump_control(&response, log_stream);
4971 }
4972 }
4973 else
4974 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4975 fmtaddr(addr->sin_addr.s_addr, 0), r);
4976
4977 free(buf);
4978 }
4979
4980 static tunnelidt new_tunnel()
4981 {
4982 tunnelidt i;
4983 for (i = 1; i < MAXTUNNEL; i++)
4984 {
4985 if (tunnel[i].state == TUNNELFREE)
4986 {
4987 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4988 if (i > config->cluster_highest_tunnelid)
4989 config->cluster_highest_tunnelid = i;
4990 return i;
4991 }
4992 }
4993 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4994 return 0;
4995 }
4996
4997 //
4998 // We're becoming the master. Do any required setup..
4999 //
5000 // This is principally telling all the plugins that we're
5001 // now a master, and telling them about all the sessions
5002 // that are active too..
5003 //
5004 void become_master(void)
5005 {
5006 int s, i;
5007 static struct event_data d[RADIUS_FDS];
5008 struct epoll_event e;
5009
5010 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5011
5012 // running a bunch of iptables commands is slow and can cause
5013 // the master to drop tunnels on takeover--kludge around the
5014 // problem by forking for the moment (note: race)
5015 if (!fork_and_close())
5016 {
5017 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5018 {
5019 if (!session[s].opened) // Not an in-use session.
5020 continue;
5021
5022 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5023 }
5024 exit(0);
5025 }
5026
5027 // add radius fds
5028 e.events = EPOLLIN;
5029 for (i = 0; i < RADIUS_FDS; i++)
5030 {
5031 d[i].type = FD_TYPE_RADIUS;
5032 d[i].index = i;
5033 e.data.ptr = &d[i];
5034
5035 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5036 }
5037 }
5038
5039 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5040 {
5041 int s, i;
5042 int count = 0;
5043 int buckets[64];
5044
5045 if (CLI_HELP_REQUESTED)
5046 return CLI_HELP_NO_ARGS;
5047
5048 time(&time_now);
5049 for (i = 0; i < 64;++i) buckets[i] = 0;
5050
5051 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5052 {
5053 int idle;
5054 if (!session[s].opened)
5055 continue;
5056
5057 idle = time_now - session[s].last_packet;
5058 idle /= 5 ; // In multiples of 5 seconds.
5059 if (idle < 0)
5060 idle = 0;
5061 if (idle > 63)
5062 idle = 63;
5063
5064 ++count;
5065 ++buckets[idle];
5066 }
5067
5068 for (i = 0; i < 63; ++i)
5069 {
5070 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5071 }
5072 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5073 cli_print(cli, "%d total sessions open.", count);
5074 return CLI_OK;
5075 }
5076
5077 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5078 {
5079 int s, i;
5080 int count = 0;
5081 int buckets[64];
5082
5083 if (CLI_HELP_REQUESTED)
5084 return CLI_HELP_NO_ARGS;
5085
5086 time(&time_now);
5087 for (i = 0; i < 64;++i) buckets[i] = 0;
5088
5089 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5090 {
5091 int open = 0, d;
5092 if (!session[s].opened)
5093 continue;
5094
5095 d = time_now - session[s].opened;
5096 if (d < 0)
5097 d = 0;
5098 while (d > 1 && open < 32)
5099 {
5100 ++open;
5101 d >>= 1; // half.
5102 }
5103 ++count;
5104 ++buckets[open];
5105 }
5106
5107 s = 1;
5108 for (i = 0; i < 30; ++i)
5109 {
5110 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5111 s <<= 1;
5112 }
5113 cli_print(cli, "%d total sessions open.", count);
5114 return CLI_OK;
5115 }
5116
5117 /* Unhide an avp.
5118 *
5119 * This unencodes the AVP using the L2TP secret and the previously
5120 * stored random vector. It overwrites the hidden data with the
5121 * unhidden AVP subformat.
5122 */
5123 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5124 {
5125 MD5_CTX ctx;
5126 uint8_t digest[16];
5127 uint8_t *last;
5128 size_t d = 0;
5129 uint16_t m = htons(type);
5130
5131 // Compute initial pad
5132 MD5_Init(&ctx);
5133 MD5_Update(&ctx, (unsigned char *) &m, 2);
5134 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5135 MD5_Update(&ctx, vector, vec_len);
5136 MD5_Final(digest, &ctx);
5137
5138 // pointer to last decoded 16 octets
5139 last = value;
5140
5141 while (len > 0)
5142 {
5143 // calculate a new pad based on the last decoded block
5144 if (d >= sizeof(digest))
5145 {
5146 MD5_Init(&ctx);
5147 MD5_Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5148 MD5_Update(&ctx, last, sizeof(digest));
5149 MD5_Final(digest, &ctx);
5150
5151 d = 0;
5152 last = value;
5153 }
5154
5155 *value++ ^= digest[d++];
5156 len--;
5157 }
5158 }
5159
5160 int find_filter(char const *name, size_t len)
5161 {
5162 int free = -1;
5163 int i;
5164
5165 for (i = 0; i < MAXFILTER; i++)
5166 {
5167 if (!*ip_filters[i].name)
5168 {
5169 if (free < 0)
5170 free = i;
5171
5172 continue;
5173 }
5174
5175 if (strlen(ip_filters[i].name) != len)
5176 continue;
5177
5178 if (!strncmp(ip_filters[i].name, name, len))
5179 return i;
5180 }
5181
5182 return free;
5183 }
5184
5185 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5186 {
5187 switch (p->op)
5188 {
5189 case FILTER_PORT_OP_EQ: return port == p->port;
5190 case FILTER_PORT_OP_NEQ: return port != p->port;
5191 case FILTER_PORT_OP_GT: return port > p->port;
5192 case FILTER_PORT_OP_LT: return port < p->port;
5193 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5194 }
5195
5196 return 0;
5197 }
5198
5199 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5200 {
5201 switch (op)
5202 {
5203 case FILTER_FLAG_OP_ANY:
5204 return (flags & sflags) || (~flags & cflags);
5205
5206 case FILTER_FLAG_OP_ALL:
5207 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5208
5209 case FILTER_FLAG_OP_EST:
5210 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5211 }
5212
5213 return 0;
5214 }
5215
5216 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5217 {
5218 uint16_t frag_offset;
5219 uint8_t proto;
5220 in_addr_t src_ip;
5221 in_addr_t dst_ip;
5222 uint16_t src_port = 0;
5223 uint16_t dst_port = 0;
5224 uint8_t flags = 0;
5225 ip_filter_rulet *rule;
5226
5227 if (len < 20) // up to end of destination address
5228 return 0;
5229
5230 if ((*buf >> 4) != 4) // IPv4
5231 return 0;
5232
5233 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5234 proto = buf[9];
5235 src_ip = *(in_addr_t *) (buf + 12);
5236 dst_ip = *(in_addr_t *) (buf + 16);
5237
5238 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5239 {
5240 int l = (buf[0] & 0xf) * 4; // length of IP header
5241 if (len < l + 4) // ports
5242 return 0;
5243
5244 src_port = ntohs(*(uint16_t *) (buf + l));
5245 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5246 if (proto == IPPROTO_TCP)
5247 {
5248 if (len < l + 14) // flags
5249 return 0;
5250
5251 flags = buf[l + 13] & 0x3f;
5252 }
5253 }
5254
5255 for (rule = ip_filters[filter].rules; rule->action; rule++)
5256 {
5257 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5258 continue;
5259
5260 if (rule->src_wild != INADDR_BROADCAST &&
5261 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5262 continue;
5263
5264 if (rule->dst_wild != INADDR_BROADCAST &&
5265 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5266 continue;
5267
5268 if (frag_offset)
5269 {
5270 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5271 continue;
5272 }
5273 else
5274 {
5275 if (rule->frag)
5276 continue;
5277
5278 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5279 {
5280 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5281 continue;
5282
5283 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5284 continue;
5285
5286 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5287 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5288 continue;
5289 }
5290 }
5291
5292 // matched
5293 rule->counter++;
5294 return rule->action == FILTER_ACTION_PERMIT;
5295 }
5296
5297 // default deny
5298 return 0;
5299 }