22187e1708904e25ec009a15d1169f600842c67e
[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 1.109 2005/06/12 06:10:29 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 snoopfd = -1; // UDP file handle for sending out intercept data
64 int *radfds = NULL; // RADIUS requests file handles
65 int ifrfd = -1; // File descriptor for routing, etc
66 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
67 int rand_fd = -1; // Random data source
68 int cluster_sockfd = -1; // Intra-cluster communications socket.
69 int epollfd = -1; // event polling
70 time_t basetime = 0; // base clock
71 char hostname[1000] = ""; // us.
72 static int tunidx; // ifr_ifindex of tun device
73 static int syslog_log = 0; // are we logging to syslog
74 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
75 uint32_t last_id = 0; // Unique ID for radius accounting
76
77 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
78 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
79
80 static void *ip_hash[256]; // Mapping from IP address to session structures.
81 struct ipv6radix {
82 int sess;
83 struct ipv6radix *branch;
84 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
85
86 // Traffic counters.
87 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
88 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
89 uint32_t eth_tx = 0;
90
91 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
92 time_t time_now = 0; // Current time in seconds since epoch.
93 static char time_now_string[64] = {0}; // Current time as a string.
94 char main_quit = 0; // True if we're in the process of exiting.
95 linked_list *loaded_plugins;
96 linked_list *plugins[MAX_PLUGIN_TYPES];
97
98 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
99 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
100
101 config_descriptt config_values[] = {
102 CONFIG("debug", debug, INT),
103 CONFIG("log_file", log_filename, STRING),
104 CONFIG("pid_file", pid_file, STRING),
105 CONFIG("random_device", random_device, STRING),
106 CONFIG("l2tp_secret", l2tpsecret, STRING),
107 CONFIG("primary_dns", default_dns1, IPv4),
108 CONFIG("secondary_dns", default_dns2, IPv4),
109 CONFIG("primary_radius", radiusserver[0], IPv4),
110 CONFIG("secondary_radius", radiusserver[1], IPv4),
111 CONFIG("primary_radius_port", radiusport[0], SHORT),
112 CONFIG("secondary_radius_port", radiusport[1], SHORT),
113 CONFIG("radius_accounting", radius_accounting, BOOL),
114 CONFIG("radius_interim", radius_interim, INT),
115 CONFIG("radius_secret", radiussecret, STRING),
116 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
117 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
118 CONFIG("bind_address", bind_address, IPv4),
119 CONFIG("peer_address", peer_address, IPv4),
120 CONFIG("send_garp", send_garp, BOOL),
121 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
122 CONFIG("throttle_buckets", num_tbfs, INT),
123 CONFIG("accounting_dir", accounting_dir, STRING),
124 CONFIG("setuid", target_uid, INT),
125 CONFIG("dump_speed", dump_speed, BOOL),
126 CONFIG("multi_read_count", multi_read_count, INT),
127 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
128 CONFIG("lock_pages", lock_pages, BOOL),
129 CONFIG("icmp_rate", icmp_rate, INT),
130 CONFIG("packet_limit", max_packets, INT),
131 CONFIG("cluster_address", cluster_address, IPv4),
132 CONFIG("cluster_interface", cluster_interface, STRING),
133 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
134 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
135 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
136 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
137 { NULL, 0, 0, 0 },
138 };
139
140 static char *plugin_functions[] = {
141 NULL,
142 "plugin_pre_auth",
143 "plugin_post_auth",
144 "plugin_packet_rx",
145 "plugin_packet_tx",
146 "plugin_timer",
147 "plugin_new_session",
148 "plugin_kill_session",
149 "plugin_control",
150 "plugin_radius_response",
151 "plugin_become_master",
152 "plugin_new_session_master",
153 };
154
155 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
156
157 // Counters for shutdown sessions
158 static sessiont shut_acct[8192];
159 static sessionidt shut_acct_n = 0;
160
161 tunnelt *tunnel = NULL; // Array of tunnel structures.
162 sessiont *session = NULL; // Array of session structures.
163 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
164 radiust *radius = NULL; // Array of radius structures.
165 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
166 ip_filtert *ip_filters = NULL; // Array of named filters.
167 static controlt *controlfree = 0;
168 struct Tstats *_statistics = NULL;
169 #ifdef RINGBUFFER
170 struct Tringbuffer *ringbuffer = NULL;
171 #endif
172
173 static void cache_ipmap(in_addr_t ip, int s);
174 static void uncache_ipmap(in_addr_t ip);
175 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
176 static void free_ip_address(sessionidt s);
177 static void dump_acct_info(int all);
178 static void sighup_handler(int sig);
179 static void sigalrm_handler(int sig);
180 static void shutdown_handler(int sig);
181 static void sigchild_handler(int sig);
182 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
183 static void update_config(void);
184 static void read_config_file(void);
185 static void initplugins(void);
186 static int add_plugin(char *plugin_name);
187 static int remove_plugin(char *plugin_name);
188 static void plugins_done(void);
189 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
190 static tunnelidt new_tunnel(void);
191 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
192
193 // on slaves, alow BGP to withdraw cleanly before exiting
194 #define QUIT_DELAY 5
195
196 // quit actions (master)
197 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
198 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
199
200 // return internal time (10ths since process startup), set f if given
201 static clockt now(double *f)
202 {
203 struct timeval t;
204 gettimeofday(&t, 0);
205 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
206 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
207 }
208
209 // work out a retry time based on try number
210 // This is a straight bounded exponential backoff.
211 // Maximum re-try time is 32 seconds. (2^5).
212 clockt backoff(uint8_t try)
213 {
214 if (try > 5) try = 5; // max backoff
215 return now(NULL) + 10 * (1 << try);
216 }
217
218
219 //
220 // Log a debug message. Typically called via the LOG macro
221 //
222 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
223 {
224 static char message[65536] = {0};
225 va_list ap;
226
227 #ifdef RINGBUFFER
228 if (ringbuffer)
229 {
230 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
231 ringbuffer->tail = 0;
232 if (ringbuffer->tail == ringbuffer->head)
233 if (++ringbuffer->head >= RINGBUFFER_SIZE)
234 ringbuffer->head = 0;
235
236 ringbuffer->buffer[ringbuffer->tail].level = level;
237 ringbuffer->buffer[ringbuffer->tail].session = s;
238 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
239 va_start(ap, format);
240 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
241 va_end(ap);
242 }
243 #endif
244
245 if (config->debug < level) return;
246
247 va_start(ap, format);
248 vsnprintf(message, sizeof(message), format, ap);
249
250 if (log_stream)
251 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
252 else if (syslog_log)
253 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
254
255 va_end(ap);
256 }
257
258 void _log_hex(int level, const char *title, const char *data, int maxsize)
259 {
260 int i, j;
261 const uint8_t *d = (const uint8_t *) data;
262
263 if (config->debug < level) return;
264
265 // No support for _log_hex to syslog
266 if (log_stream)
267 {
268 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
269 setvbuf(log_stream, NULL, _IOFBF, 16384);
270
271 for (i = 0; i < maxsize; )
272 {
273 fprintf(log_stream, "%4X: ", i);
274 for (j = i; j < maxsize && j < (i + 16); j++)
275 {
276 fprintf(log_stream, "%02X ", d[j]);
277 if (j == i + 7)
278 fputs(": ", log_stream);
279 }
280
281 for (; j < i + 16; j++)
282 {
283 fputs(" ", log_stream);
284 if (j == i + 7)
285 fputs(": ", log_stream);
286 }
287
288 fputs(" ", log_stream);
289 for (j = i; j < maxsize && j < (i + 16); j++)
290 {
291 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
292 fputc(d[j], log_stream);
293 else
294 fputc('.', log_stream);
295
296 if (j == i + 7)
297 fputs(" ", log_stream);
298 }
299
300 i = j;
301 fputs("\n", log_stream);
302 }
303
304 fflush(log_stream);
305 setbuf(log_stream, NULL);
306 }
307 }
308
309 // update a counter, accumulating 2^32 wraps
310 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
311 {
312 uint32_t new = *counter + delta;
313 if (new < *counter)
314 (*wrap)++;
315
316 *counter = new;
317 }
318
319 // initialise the random generator
320 static void initrandom(char *source)
321 {
322 static char path[sizeof(config->random_device)] = "*undefined*";
323
324 // reinitialise only if we are forced to do so or if the config has changed
325 if (source && !strncmp(path, source, sizeof(path)))
326 return;
327
328 // close previous source, if any
329 if (rand_fd >= 0) close(rand_fd);
330
331 rand_fd = -1;
332
333 if (source)
334 {
335 // register changes
336 snprintf(path, sizeof(path), "%s", source);
337
338 if (*path == '/')
339 {
340 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
341 if (rand_fd < 0)
342 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
343 path, strerror(errno));
344 }
345 }
346
347 // no source: seed prng
348 {
349 unsigned seed = time_now ^ getpid();
350 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
351 srand(seed);
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(0);
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] > 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 port
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 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
610
611 // Control
612 memset(&addr, 0, sizeof(addr));
613 addr.sin_family = AF_INET;
614 addr.sin_port = htons(NSCTL_PORT);
615 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
616 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
617 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
618 {
619 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
620 exit(1);
621 }
622 }
623
624 //
625 // Find session by IP, < 1 for not found
626 //
627 // Confusingly enough, this 'ip' must be
628 // in _network_ order. This being the common
629 // case when looking it up from IP packet headers.
630 //
631 // We actually use this cache for two things.
632 // #1. For used IP addresses, this maps to the
633 // session ID that it's used by.
634 // #2. For un-used IP addresses, this maps to the
635 // index into the pool table that contains that
636 // IP address.
637 //
638
639 static int lookup_ipmap(in_addr_t ip)
640 {
641 uint8_t *a = (uint8_t *) &ip;
642 uint8_t **d = (uint8_t **) ip_hash;
643
644 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
645 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
646 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
647
648 return (int) (intptr_t) d[(size_t) *a];
649 }
650
651 static int lookup_ipv6map(struct in6_addr ip)
652 {
653 struct ipv6radix *curnode;
654 int i;
655 int s;
656 char ipv6addr[INET6_ADDRSTRLEN];
657
658 curnode = &ipv6_hash[ip.s6_addr[0]];
659 i = 1;
660 s = curnode->sess;
661
662 while (s == 0 && i < 15 && curnode->branch != NULL)
663 {
664 curnode = &curnode->branch[ip.s6_addr[i]];
665 s = curnode->sess;
666 i++;
667 }
668
669 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
670 inet_ntop(AF_INET6, &ip, ipv6addr,
671 INET6_ADDRSTRLEN),
672 s);
673
674 return s;
675 }
676
677 sessionidt sessionbyip(in_addr_t ip)
678 {
679 int s = lookup_ipmap(ip);
680 CSTAT(sessionbyip);
681
682 if (s > 0 && s < MAXSESSION && session[s].opened)
683 return (sessionidt) s;
684
685 return 0;
686 }
687
688 sessionidt sessionbyipv6(struct in6_addr ip)
689 {
690 int s;
691 CSTAT(sessionbyipv6);
692
693 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
694 (ip.s6_addr[0] == 0xFE && ip.s6_addr[1] == 0x80 &&
695 (ip.s6_addr16[1] == ip.s6_addr16[2] == ip.s6_addr16[3] == 0))) {
696 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
697 } else {
698 s = lookup_ipv6map(ip);
699 }
700
701 if (s > 0 && s < MAXSESSION && session[s].opened)
702 return s;
703
704 return 0;
705 }
706
707 //
708 // Take an IP address in HOST byte order and
709 // add it to the sessionid by IP cache.
710 //
711 // (It's actually cached in network order)
712 //
713 static void cache_ipmap(in_addr_t ip, int s)
714 {
715 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
716 uint8_t *a = (uint8_t *) &nip;
717 uint8_t **d = (uint8_t **) ip_hash;
718 int i;
719
720 for (i = 0; i < 3; i++)
721 {
722 if (!d[(size_t) a[i]])
723 {
724 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
725 return;
726 }
727
728 d = (uint8_t **) d[(size_t) a[i]];
729 }
730
731 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
732
733 if (s > 0)
734 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
735
736 else if (s == 0)
737 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
738 // else a map to an ip pool index.
739 }
740
741 static void uncache_ipmap(in_addr_t ip)
742 {
743 cache_ipmap(ip, 0); // Assign it to the NULL session.
744 }
745
746 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
747 {
748 int i;
749 int bytes;
750 struct ipv6radix *curnode;
751 char ipv6addr[INET6_ADDRSTRLEN];
752
753 curnode = &ipv6_hash[ip.s6_addr[0]];
754
755 bytes = prefixlen >> 3;
756 i = 1;
757 while (i < bytes) {
758 if (curnode->branch == NULL)
759 {
760 if (!(curnode->branch = calloc(256,
761 sizeof (struct ipv6radix))))
762 return;
763 }
764 curnode = &curnode->branch[ip.s6_addr[i]];
765 i++;
766 }
767
768 curnode->sess = s;
769
770 if (s > 0)
771 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
772 inet_ntop(AF_INET6, &ip, ipv6addr,
773 INET6_ADDRSTRLEN),
774 prefixlen);
775 else if (s == 0)
776 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
777 inet_ntop(AF_INET6, &ip, ipv6addr,
778 INET6_ADDRSTRLEN),
779 prefixlen);
780 }
781
782 //
783 // CLI list to dump current ipcache.
784 //
785 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
786 {
787 char **d = (char **) ip_hash, **e, **f, **g;
788 int i, j, k, l;
789 int count = 0;
790
791 if (CLI_HELP_REQUESTED)
792 return CLI_HELP_NO_ARGS;
793
794 cli_print(cli, "%7s %s", "Sess#", "IP Address");
795
796 for (i = 0; i < 256; ++i)
797 {
798 if (!d[i])
799 continue;
800 e = (char **) d[i];
801 for (j = 0; j < 256; ++j)
802 {
803 if (!e[j])
804 continue;
805 f = (char **) e[j];
806 for (k = 0; k < 256; ++k)
807 {
808 if (!f[k])
809 continue;
810 g = (char **)f[k];
811 for (l = 0; l < 256; ++l)
812 {
813 if (!g[l])
814 continue;
815 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
816 ++count;
817 }
818 }
819 }
820 }
821 cli_print(cli, "%d entries in cache", count);
822 return CLI_OK;
823 }
824
825
826 // Find session by username, 0 for not found
827 // walled garden users aren't authenticated, so the username is
828 // reasonably useless. Ignore them to avoid incorrect actions
829 //
830 // This is VERY inefficent. Don't call it often. :)
831 //
832 sessionidt sessionbyuser(char *username)
833 {
834 int s;
835 CSTAT(sessionbyuser);
836
837 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
838 {
839 if (!session[s].opened)
840 continue;
841
842 if (session[s].walled_garden)
843 continue; // Skip walled garden users.
844
845 if (!strncmp(session[s].user, username, 128))
846 return s;
847
848 }
849 return 0; // Not found.
850 }
851
852 void send_garp(in_addr_t ip)
853 {
854 int s;
855 struct ifreq ifr;
856 uint8_t mac[6];
857
858 s = socket(PF_INET, SOCK_DGRAM, 0);
859 if (s < 0)
860 {
861 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
862 return;
863 }
864 memset(&ifr, 0, sizeof(ifr));
865 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
866 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
867 {
868 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
869 close(s);
870 return;
871 }
872 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
873 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
874 {
875 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
876 close(s);
877 return;
878 }
879 close(s);
880 sendarp(ifr.ifr_ifindex, mac, ip);
881 }
882
883 static sessiont *sessiontbysessionidt(sessionidt s)
884 {
885 if (!s || s >= MAXSESSION) return NULL;
886 return &session[s];
887 }
888
889 static sessionidt sessionidtbysessiont(sessiont *s)
890 {
891 sessionidt val = s-session;
892 if (s < session || val >= MAXSESSION) return 0;
893 return val;
894 }
895
896 // actually send a control message for a specific tunnel
897 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
898 {
899 struct sockaddr_in addr;
900
901 CSTAT(tunnelsend);
902
903 if (!t)
904 {
905 static int backtrace_count = 0;
906 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
907 STAT(tunnel_tx_errors);
908 log_backtrace(backtrace_count, 5)
909 return;
910 }
911
912 if (!tunnel[t].ip)
913 {
914 static int backtrace_count = 0;
915 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
916 log_backtrace(backtrace_count, 5)
917 STAT(tunnel_tx_errors);
918 return;
919 }
920
921 memset(&addr, 0, sizeof(addr));
922 addr.sin_family = AF_INET;
923 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
924 addr.sin_port = htons(tunnel[t].port);
925
926 // sequence expected, if sequence in message
927 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
928
929 // If this is a control message, deal with retries
930 if (*buf & 0x80)
931 {
932 tunnel[t].last = time_now; // control message sent
933 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
934 if (tunnel[t].try > 1)
935 {
936 STAT(tunnel_retries);
937 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
938 }
939 }
940
941 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
942 {
943 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
944 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
945 STAT(tunnel_tx_errors);
946 return;
947 }
948
949 LOG_HEX(5, "Send Tunnel Data", buf, l);
950 STAT(tunnel_tx_packets);
951 INC_STAT(tunnel_tx_bytes, l);
952 }
953
954 //
955 // Tiny helper function to write data to
956 // the 'tun' device.
957 //
958 int tun_write(uint8_t * data, int size)
959 {
960 return write(tunfd, data, size);
961 }
962
963 // process outgoing (to tunnel) IP
964 //
965 static void processipout(uint8_t * buf, int len)
966 {
967 sessionidt s;
968 sessiont *sp;
969 tunnelidt t;
970 in_addr_t ip;
971
972 char *data = buf; // Keep a copy of the originals.
973 int size = len;
974
975 uint8_t b[MAXETHER + 20];
976
977 CSTAT(processipout);
978
979 if (len < MIN_IP_SIZE)
980 {
981 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
982 STAT(tun_rx_errors);
983 return;
984 }
985 if (len >= MAXETHER)
986 {
987 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
988 STAT(tun_rx_errors);
989 return;
990 }
991
992 // Skip the tun header
993 buf += 4;
994 len -= 4;
995
996 // Got an IP header now
997 if (*(uint8_t *)(buf) >> 4 != 4)
998 {
999 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1000 return;
1001 }
1002
1003 ip = *(uint32_t *)(buf + 16);
1004 if (!(s = sessionbyip(ip)))
1005 {
1006 // Is this a packet for a session that doesn't exist?
1007 static int rate = 0; // Number of ICMP packets we've sent this second.
1008 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1009
1010 if (last != time_now)
1011 {
1012 last = time_now;
1013 rate = 0;
1014 }
1015
1016 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1017 {
1018 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1019 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1020 config->bind_address ? config->bind_address : my_address, buf, len);
1021 }
1022 return;
1023 }
1024 t = session[s].tunnel;
1025 sp = &session[s];
1026
1027 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1028 if (config->max_packets > 0)
1029 {
1030 if (sess_local[s].last_packet_out == TIME)
1031 {
1032 int max = config->max_packets;
1033
1034 // All packets for throttled sessions are handled by the
1035 // master, so further limit by using the throttle rate.
1036 // A bit of a kludge, since throttle rate is in kbps,
1037 // but should still be generous given our average DSL
1038 // packet size is 200 bytes: a limit of 28kbps equates
1039 // to around 180 packets per second.
1040 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1041 max = sp->throttle_out;
1042
1043 if (++sess_local[s].packets_out > max)
1044 {
1045 sess_local[s].packets_dropped++;
1046 return;
1047 }
1048 }
1049 else
1050 {
1051 if (sess_local[s].packets_dropped)
1052 {
1053 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1054 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1055 sess_local[s].packets_dropped, sess_local[s].packets_out,
1056 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1057 sp->user);
1058 }
1059
1060 sess_local[s].last_packet_out = TIME;
1061 sess_local[s].packets_out = 1;
1062 sess_local[s].packets_dropped = 0;
1063 }
1064 }
1065
1066 // run access-list if any
1067 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1068 return;
1069
1070 if (sp->tbf_out)
1071 {
1072 // Are we throttling this session?
1073 if (config->cluster_iam_master)
1074 tbf_queue_packet(sp->tbf_out, data, size);
1075 else
1076 master_throttle_packet(sp->tbf_out, data, size);
1077 return;
1078 }
1079 else if (sp->walled_garden && !config->cluster_iam_master)
1080 {
1081 // We are walled-gardening this
1082 master_garden_packet(s, data, size);
1083 return;
1084 }
1085
1086 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1087
1088 // Add on L2TP header
1089 {
1090 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1091 if (!p) return;
1092 tunnelsend(b, len + (p-b), t); // send it...
1093 }
1094
1095 // Snooping this session, send it to intercept box
1096 if (sp->snoop_ip && sp->snoop_port)
1097 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1098
1099 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1100 sp->cout_delta += len;
1101 sp->pout++;
1102 udp_tx += len;
1103
1104 sess_local[s].cout += len; // To send to master..
1105 sess_local[s].pout++;
1106 }
1107
1108 // process outgoing (to tunnel) IPv6
1109 //
1110 static void processipv6out(uint8_t * buf, int len)
1111 {
1112 sessionidt s;
1113 sessiont *sp;
1114 tunnelidt t;
1115 in_addr_t ip;
1116 struct in6_addr ip6;
1117
1118 char *data = buf; // Keep a copy of the originals.
1119 int size = len;
1120
1121 uint8_t b[MAXETHER + 20];
1122
1123 CSTAT(processipv6out);
1124
1125 if (len < MIN_IP_SIZE)
1126 {
1127 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1128 STAT(tunnel_tx_errors);
1129 return;
1130 }
1131 if (len >= MAXETHER)
1132 {
1133 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1134 STAT(tunnel_tx_errors);
1135 return;
1136 }
1137
1138 // Skip the tun header
1139 buf += 4;
1140 len -= 4;
1141
1142 // Got an IP header now
1143 if (*(uint8_t *)(buf) >> 4 != 6)
1144 {
1145 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1146 return;
1147 }
1148
1149 ip6 = *(struct in6_addr *)(buf+24);
1150 s = sessionbyipv6(ip6);
1151
1152 if (s == 0)
1153 {
1154 ip = *(uint32_t *)(buf + 32);
1155 s = sessionbyip(ip);
1156 }
1157
1158 if (s == 0)
1159 {
1160 // Is this a packet for a session that doesn't exist?
1161 static int rate = 0; // Number of ICMP packets we've sent this second.
1162 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1163
1164 if (last != time_now)
1165 {
1166 last = time_now;
1167 rate = 0;
1168 }
1169
1170 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1171 {
1172 // FIXME: Should send icmp6 host unreachable
1173 }
1174 return;
1175 }
1176 t = session[s].tunnel;
1177 sp = &session[s];
1178
1179 // FIXME: add DoS prevention/filters?
1180
1181 if (sp->tbf_out)
1182 {
1183 // Are we throttling this session?
1184 if (config->cluster_iam_master)
1185 tbf_queue_packet(sp->tbf_out, data, size);
1186 else
1187 master_throttle_packet(sp->tbf_out, data, size);
1188 return;
1189 }
1190 else if (sp->walled_garden && !config->cluster_iam_master)
1191 {
1192 // We are walled-gardening this
1193 master_garden_packet(s, data, size);
1194 return;
1195 }
1196
1197 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1198
1199 // Add on L2TP header
1200 {
1201 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIPV6);
1202 if (!p) return;
1203 tunnelsend(b, len + (p-b), t); // send it...
1204 }
1205
1206 // Snooping this session, send it to intercept box
1207 if (sp->snoop_ip && sp->snoop_port)
1208 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1209
1210 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1211 sp->cout_delta += len;
1212 sp->pout++;
1213 udp_tx += len;
1214
1215 sess_local[s].cout += len; // To send to master..
1216 sess_local[s].pout++;
1217 }
1218
1219 //
1220 // Helper routine for the TBF filters.
1221 // Used to send queued data in to the user!
1222 //
1223 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1224 {
1225 sessiont *sp;
1226 tunnelidt t;
1227 in_addr_t ip;
1228
1229 uint8_t b[MAXETHER + 20];
1230
1231 if (len < 0 || len > MAXETHER)
1232 {
1233 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1234 return;
1235 }
1236
1237 // Skip the tun header
1238 buf += 4;
1239 len -= 4;
1240
1241 ip = *(in_addr_t *)(buf + 16);
1242
1243 if (!session[s].ip)
1244 return;
1245
1246 t = session[s].tunnel;
1247 sp = &session[s];
1248
1249 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1250
1251 // Add on L2TP header
1252 {
1253 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1254 if (!p) return;
1255 tunnelsend(b, len + (p-b), t); // send it...
1256 }
1257
1258 // Snooping this session.
1259 if (sp->snoop_ip && sp->snoop_port)
1260 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1261
1262 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1263 sp->cout_delta += len;
1264 sp->pout++;
1265 udp_tx += len;
1266
1267 sess_local[s].cout += len; // To send to master..
1268 sess_local[s].pout++;
1269 }
1270
1271 // add an AVP (16 bit)
1272 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1273 {
1274 uint16_t l = (m ? 0x8008 : 0x0008);
1275 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1276 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1277 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1278 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1279 c->length += 8;
1280 }
1281
1282 // add an AVP (32 bit)
1283 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1284 {
1285 uint16_t l = (m ? 0x800A : 0x000A);
1286 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1287 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1288 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1289 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1290 c->length += 10;
1291 }
1292
1293 // add an AVP (string)
1294 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1295 {
1296 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1297 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1298 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1299 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1300 memcpy(c->buf + c->length + 6, val, strlen(val));
1301 c->length += 6 + strlen(val);
1302 }
1303
1304 // add a binary AVP
1305 static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
1306 {
1307 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1308 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1309 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1310 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1311 memcpy(c->buf + c->length + 6, val, len);
1312 c->length += 6 + len;
1313 }
1314
1315 // new control connection
1316 static controlt *controlnew(uint16_t mtype)
1317 {
1318 controlt *c;
1319 if (!controlfree)
1320 c = malloc(sizeof(controlt));
1321 else
1322 {
1323 c = controlfree;
1324 controlfree = c->next;
1325 }
1326 assert(c);
1327 c->next = 0;
1328 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1329 c->length = 12;
1330 control16(c, 0, mtype, 1);
1331 return c;
1332 }
1333
1334 // send zero block if nothing is waiting
1335 // (ZLB send).
1336 static void controlnull(tunnelidt t)
1337 {
1338 uint8_t buf[12];
1339 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1340 return;
1341
1342 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1343 *(uint16_t *) (buf + 2) = htons(12); // length
1344 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1345 *(uint16_t *) (buf + 6) = htons(0); // session
1346 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1347 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1348 tunnelsend(buf, 12, t);
1349 }
1350
1351 // add a control message to a tunnel, and send if within window
1352 static void controladd(controlt * c, tunnelidt t, sessionidt far)
1353 {
1354 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1355 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1356 *(uint16_t *) (c->buf + 6) = htons(far); // session
1357 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1358 tunnel[t].ns++; // advance sequence
1359 // link in message in to queue
1360 if (tunnel[t].controlc)
1361 tunnel[t].controle->next = c;
1362 else
1363 tunnel[t].controls = c;
1364
1365 tunnel[t].controle = c;
1366 tunnel[t].controlc++;
1367
1368 // send now if space in window
1369 if (tunnel[t].controlc <= tunnel[t].window)
1370 {
1371 tunnel[t].try = 0; // first send
1372 tunnelsend(c->buf, c->length, t);
1373 }
1374 }
1375
1376 //
1377 // Throttle or Unthrottle a session
1378 //
1379 // Throttle the data from/to through a session to no more than
1380 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1381 // user).
1382 //
1383 // If either value is -1, the current value is retained for that
1384 // direction.
1385 //
1386 void throttle_session(sessionidt s, int rate_in, int rate_out)
1387 {
1388 if (!session[s].opened)
1389 return; // No-one home.
1390
1391 if (!*session[s].user)
1392 return; // User not logged in
1393
1394 if (rate_in >= 0)
1395 {
1396 int bytes = rate_in * 1024 / 8; // kbits to bytes
1397 if (session[s].tbf_in)
1398 free_tbf(session[s].tbf_in);
1399
1400 if (rate_in > 0)
1401 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1402 else
1403 session[s].tbf_in = 0;
1404
1405 session[s].throttle_in = rate_in;
1406 }
1407
1408 if (rate_out >= 0)
1409 {
1410 int bytes = rate_out * 1024 / 8;
1411 if (session[s].tbf_out)
1412 free_tbf(session[s].tbf_out);
1413
1414 if (rate_out > 0)
1415 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1416 else
1417 session[s].tbf_out = 0;
1418
1419 session[s].throttle_out = rate_out;
1420 }
1421 }
1422
1423 // add/remove filters from session (-1 = no change)
1424 static void filter_session(sessionidt s, int filter_in, int filter_out)
1425 {
1426 if (!session[s].opened)
1427 return; // No-one home.
1428
1429 if (!*session[s].user)
1430 return; // User not logged in
1431
1432 // paranoia
1433 if (filter_in > MAXFILTER) filter_in = -1;
1434 if (filter_out > MAXFILTER) filter_out = -1;
1435 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1436 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1437
1438 if (filter_in >= 0)
1439 {
1440 if (session[s].filter_in)
1441 ip_filters[session[s].filter_in - 1].used--;
1442
1443 if (filter_in > 0)
1444 ip_filters[filter_in - 1].used++;
1445
1446 session[s].filter_in = filter_in;
1447 }
1448
1449 if (filter_out >= 0)
1450 {
1451 if (session[s].filter_out)
1452 ip_filters[session[s].filter_out - 1].used--;
1453
1454 if (filter_out > 0)
1455 ip_filters[filter_out - 1].used++;
1456
1457 session[s].filter_out = filter_out;
1458 }
1459 }
1460
1461 // start tidy shutdown of session
1462 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1463 {
1464 int walled_garden = session[s].walled_garden;
1465
1466
1467 CSTAT(sessionshutdown);
1468
1469 if (!session[s].opened)
1470 {
1471 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1472 return; // not a live session
1473 }
1474
1475 if (!session[s].die)
1476 {
1477 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1478 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1479 run_plugins(PLUGIN_KILL_SESSION, &data);
1480 }
1481
1482 if (session[s].ip && !walled_garden && !session[s].die)
1483 {
1484 // RADIUS Stop message
1485 uint16_t r = sess_local[s].radius;
1486 if (!r)
1487 r = radiusnew(s);
1488
1489 if (r)
1490 {
1491 // stop, if not already trying
1492 if (radius[r].state != RADIUSSTOP)
1493 radiussend(r, RADIUSSTOP);
1494 }
1495 else
1496 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1497
1498 // Save counters to dump to accounting file
1499 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1500 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1501 }
1502
1503 if (session[s].ip)
1504 { // IP allocated, clear and unroute
1505 int r;
1506 int routed = 0;
1507 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1508 {
1509 if ((session[s].ip & session[s].route[r].mask) ==
1510 (session[s].route[r].ip & session[s].route[r].mask))
1511 routed++;
1512
1513 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1514 session[s].route[r].ip = 0;
1515 }
1516
1517 if (session[s].ip_pool_index == -1) // static ip
1518 {
1519 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1520 session[s].ip = 0;
1521 }
1522 else
1523 free_ip_address(s);
1524
1525 // unroute IPv6, if setup
1526 if (session[s].flags & SF_IPV6_ROUTED)
1527 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1528 }
1529
1530 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1531 throttle_session(s, 0, 0);
1532
1533 if (result)
1534 { // Send CDN
1535 controlt *c = controlnew(14); // sending CDN
1536 if (error)
1537 {
1538 char buf[4];
1539 *(uint16_t *) buf = htons(result);
1540 *(uint16_t *) (buf+2) = htons(error);
1541 controlb(c, 1, buf, 4, 1);
1542 }
1543 else
1544 control16(c, 1, result, 1);
1545
1546 control16(c, 14, s, 1); // assigned session (our end)
1547 controladd(c, session[s].tunnel, session[s].far); // send the message
1548 }
1549
1550 if (!session[s].die)
1551 session[s].die = TIME + 150; // Clean up in 15 seconds
1552
1553 // update filter refcounts
1554 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1555 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1556
1557 cluster_send_session(s);
1558 }
1559
1560 void sendipcp(tunnelidt t, sessionidt s)
1561 {
1562 uint8_t buf[MAXCONTROL];
1563 uint16_t r = sess_local[s].radius;
1564 uint8_t *q;
1565
1566 CSTAT(sendipcp);
1567
1568 if (!r)
1569 r = radiusnew(s);
1570
1571 if (!r)
1572 {
1573 sessionshutdown(s, "No free RADIUS sessions for IPCP", 3, 0);
1574 return;
1575 }
1576
1577 if (radius[r].state != RADIUSIPCP)
1578 {
1579 radius[r].state = RADIUSIPCP;
1580 radius[r].try = 0;
1581 }
1582
1583 radius[r].retry = backoff(radius[r].try++);
1584 if (radius[r].try > 10)
1585 {
1586 radiusclear(r, s); // Clear radius session.
1587 sessionshutdown(s, "No reply to IPCP.", 3, 0);
1588 return;
1589 }
1590
1591 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1592 if (!q) return;
1593
1594 *q = ConfigReq;
1595 q[1] = r >> RADIUS_SHIFT; // ID, dont care, we only send one type of request
1596 *(uint16_t *) (q + 2) = htons(10);
1597 q[4] = 3;
1598 q[5] = 6;
1599 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1600 config->bind_address ? config->bind_address :
1601 my_address; // send my IP
1602
1603 tunnelsend(buf, 10 + (q - buf), t); // send it
1604 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1605
1606 // If we have an IPv6 prefix length configured, assume we should
1607 // try to negotiate an IPv6 session as well. Unless we've had a
1608 // (N)ACK for IPV6CP.
1609 if (config->ipv6_prefix.s6_addr[0] > 0 &&
1610 !(session[s].flags & SF_IPV6CP_ACKED) &&
1611 !(session[s].flags & SF_IPV6_NACKED))
1612 {
1613 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
1614 if (!q) return;
1615
1616 *q = ConfigReq;
1617 q[1] = r >> RADIUS_SHIFT; // ID, don't care, we
1618 // only send one type
1619 // of request
1620 *(uint16_t *) (q + 2) = htons(14);
1621 q[4] = 1;
1622 q[5] = 10;
1623 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1624 *(uint32_t *) (q + 10) = 0;
1625 q[13] = 1;
1626
1627 tunnelsend(buf, 14 + (q - buf), t); // send it
1628 }
1629 }
1630
1631 static void sessionclear(sessionidt s)
1632 {
1633 memset(&session[s], 0, sizeof(session[s]));
1634 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1635 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1636
1637 session[s].tunnel = T_FREE; // Mark it as free.
1638 session[s].next = sessionfree;
1639 sessionfree = s;
1640 }
1641
1642 // kill a session now
1643 void sessionkill(sessionidt s, char *reason)
1644 {
1645
1646 CSTAT(sessionkill);
1647
1648 if (!session[s].opened) // not alive
1649 return;
1650
1651 if (session[s].next)
1652 {
1653 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1654 return;
1655 }
1656
1657 session[s].die = TIME;
1658 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1659 if (sess_local[s].radius)
1660 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1661
1662 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1663 sessionclear(s);
1664 cluster_send_session(s);
1665 }
1666
1667 static void tunnelclear(tunnelidt t)
1668 {
1669 if (!t) return;
1670 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1671 tunnel[t].state = TUNNELFREE;
1672 }
1673
1674 // kill a tunnel now
1675 static void tunnelkill(tunnelidt t, char *reason)
1676 {
1677 sessionidt s;
1678 controlt *c;
1679
1680 CSTAT(tunnelkill);
1681
1682 tunnel[t].state = TUNNELDIE;
1683
1684 // free control messages
1685 while ((c = tunnel[t].controls))
1686 {
1687 controlt * n = c->next;
1688 tunnel[t].controls = n;
1689 tunnel[t].controlc--;
1690 c->next = controlfree;
1691 controlfree = c;
1692 }
1693 // kill sessions
1694 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1695 if (session[s].tunnel == t)
1696 sessionkill(s, reason);
1697
1698 // free tunnel
1699 tunnelclear(t);
1700 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1701 cli_tunnel_actions[t].action = 0;
1702 cluster_send_tunnel(t);
1703 }
1704
1705 // shut down a tunnel cleanly
1706 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1707 {
1708 sessionidt s;
1709
1710 CSTAT(tunnelshutdown);
1711
1712 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1713 {
1714 // never set up, can immediately kill
1715 tunnelkill(t, reason);
1716 return;
1717 }
1718 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1719
1720 // close session
1721 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1722 if (session[s].tunnel == t)
1723 sessionshutdown(s, reason, 0, 0);
1724
1725 tunnel[t].state = TUNNELDIE;
1726 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1727 cluster_send_tunnel(t);
1728 // TBA - should we wait for sessions to stop?
1729 if (result)
1730 {
1731 controlt *c = controlnew(4); // sending StopCCN
1732 if (error)
1733 {
1734 char buf[64];
1735 int l = 4;
1736 *(uint16_t *) buf = htons(result);
1737 *(uint16_t *) (buf+2) = htons(error);
1738 if (msg)
1739 {
1740 int m = strlen(msg);
1741 if (m + 4 > sizeof(buf))
1742 m = sizeof(buf) - 4;
1743
1744 memcpy(buf+4, msg, m);
1745 l += m;
1746 }
1747
1748 controlb(c, 1, buf, l, 1);
1749 }
1750 else
1751 control16(c, 1, result, 1);
1752
1753 control16(c, 9, t, 1); // assigned tunnel (our end)
1754 controladd(c, t, 0); // send the message
1755 }
1756 }
1757
1758 // read and process packet on tunnel (UDP)
1759 void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
1760 {
1761 char *chapresponse = NULL;
1762 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1763 uint8_t *p = buf + 2;
1764
1765
1766 CSTAT(processudp);
1767
1768 udp_rx += len;
1769 udp_rx_pkt++;
1770 LOG_HEX(5, "UDP Data", buf, len);
1771 STAT(tunnel_rx_packets);
1772 INC_STAT(tunnel_rx_bytes, len);
1773 if (len < 6)
1774 {
1775 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1776 STAT(tunnel_rx_errors);
1777 return;
1778 }
1779 if ((buf[1] & 0x0F) != 2)
1780 {
1781 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1782 STAT(tunnel_rx_errors);
1783 return;
1784 }
1785 if (*buf & 0x40)
1786 { // length
1787 l = ntohs(*(uint16_t *) p);
1788 p += 2;
1789 }
1790 t = ntohs(*(uint16_t *) p);
1791 p += 2;
1792 s = ntohs(*(uint16_t *) p);
1793 p += 2;
1794 if (s >= MAXSESSION)
1795 {
1796 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1797 STAT(tunnel_rx_errors);
1798 return;
1799 }
1800 if (t >= MAXTUNNEL)
1801 {
1802 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1803 STAT(tunnel_rx_errors);
1804 return;
1805 }
1806 if (*buf & 0x08)
1807 { // ns/nr
1808 ns = ntohs(*(uint16_t *) p);
1809 p += 2;
1810 nr = ntohs(*(uint16_t *) p);
1811 p += 2;
1812 }
1813 if (*buf & 0x02)
1814 { // offset
1815 uint16_t o = ntohs(*(uint16_t *) p);
1816 p += o + 2;
1817 }
1818 if ((p - buf) > l)
1819 {
1820 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1821 STAT(tunnel_rx_errors);
1822 return;
1823 }
1824 l -= (p - buf);
1825 if (*buf & 0x80)
1826 { // control
1827 uint16_t message = 0xFFFF; // message type
1828 uint8_t fatal = 0;
1829 uint8_t mandatory = 0;
1830 uint8_t authtype = 0; // proxy auth type
1831 uint16_t asession = 0; // assigned session
1832 uint32_t amagic = 0; // magic number
1833 uint8_t aflags = 0; // flags from last LCF
1834 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1835 char called[MAXTEL] = ""; // called number
1836 char calling[MAXTEL] = ""; // calling number
1837
1838 if (!config->cluster_iam_master)
1839 {
1840 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1841 return;
1842 }
1843
1844 // control messages must have bits 0x80|0x40|0x08
1845 // (type, length and sequence) set, and bits 0x02|0x01
1846 // (offset and priority) clear
1847 if ((*buf & 0xCB) != 0xC8)
1848 {
1849 LOG(1, s, t, "Bad control header %02X\n", *buf);
1850 STAT(tunnel_rx_errors);
1851 return;
1852 }
1853
1854 // check for duplicate tunnel open message
1855 if (!t && ns == 0)
1856 {
1857 int i;
1858
1859 //
1860 // Is this a duplicate of the first packet? (SCCRQ)
1861 //
1862 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1863 {
1864 if (tunnel[i].state != TUNNELOPENING ||
1865 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1866 tunnel[i].port != ntohs(addr->sin_port) )
1867 continue;
1868 t = i;
1869 LOG(3, s, t, "Duplicate SCCRQ?\n");
1870 break;
1871 }
1872 }
1873
1874 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1875 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1876
1877 // if no tunnel specified, assign one
1878 if (!t)
1879 {
1880 if (!(t = new_tunnel()))
1881 {
1882 LOG(1, 0, 0, "No more tunnels\n");
1883 STAT(tunnel_overflow);
1884 return;
1885 }
1886 tunnelclear(t);
1887 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1888 tunnel[t].port = ntohs(addr->sin_port);
1889 tunnel[t].window = 4; // default window
1890 STAT(tunnel_created);
1891 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1892 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1893 }
1894
1895 // If the 'ns' just received is not the 'nr' we're
1896 // expecting, just send an ack and drop it.
1897 //
1898 // if 'ns' is less, then we got a retransmitted packet.
1899 // if 'ns' is greater than missed a packet. Either way
1900 // we should ignore it.
1901 if (ns != tunnel[t].nr)
1902 {
1903 // is this the sequence we were expecting?
1904 STAT(tunnel_rx_errors);
1905 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1906 t, ns, tunnel[t].nr);
1907
1908 if (l) // Is this not a ZLB?
1909 controlnull(t);
1910 return;
1911 }
1912
1913 // This is used to time out old tunnels
1914 tunnel[t].lastrec = time_now;
1915
1916 // check sequence of this message
1917 {
1918 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1919 // some to clear maybe?
1920 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1921 {
1922 controlt *c = tunnel[t].controls;
1923 tunnel[t].controls = c->next;
1924 tunnel[t].controlc--;
1925 c->next = controlfree;
1926 controlfree = c;
1927 skip--;
1928 tunnel[t].try = 0; // we have progress
1929 }
1930
1931 // receiver advance (do here so quoted correctly in any sends below)
1932 if (l) tunnel[t].nr = (ns + 1);
1933 if (skip < 0) skip = 0;
1934 if (skip < tunnel[t].controlc)
1935 {
1936 // some control packets can now be sent that were previous stuck out of window
1937 int tosend = tunnel[t].window - skip;
1938 controlt *c = tunnel[t].controls;
1939 while (c && skip)
1940 {
1941 c = c->next;
1942 skip--;
1943 }
1944 while (c && tosend)
1945 {
1946 tunnel[t].try = 0; // first send
1947 tunnelsend(c->buf, c->length, t);
1948 c = c->next;
1949 tosend--;
1950 }
1951 }
1952 if (!tunnel[t].controlc)
1953 tunnel[t].retry = 0; // caught up
1954 }
1955 if (l)
1956 { // if not a null message
1957 int result = 0;
1958 int error = 0;
1959 char *msg = 0;
1960
1961 // process AVPs
1962 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1963 {
1964 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1965 uint8_t *b = p;
1966 uint8_t flags = *p;
1967 uint16_t mtype;
1968 if (n > l)
1969 {
1970 LOG(1, s, t, "Invalid length in AVP\n");
1971 STAT(tunnel_rx_errors);
1972 return;
1973 }
1974 p += n; // next
1975 l -= n;
1976 if (flags & 0x3C) // reserved bits, should be clear
1977 {
1978 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1979 fatal = flags;
1980 result = 2; // general error
1981 error = 3; // reserved field non-zero
1982 msg = 0;
1983 continue; // next
1984 }
1985 b += 2;
1986 if (*(uint16_t *) (b))
1987 {
1988 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1989 fatal = flags;
1990 result = 2; // general error
1991 error = 6; // generic vendor-specific error
1992 msg = "unsupported vendor-specific";
1993 continue; // next
1994 }
1995 b += 2;
1996 mtype = ntohs(*(uint16_t *) (b));
1997 b += 2;
1998 n -= 6;
1999
2000 if (flags & 0x40)
2001 {
2002 uint16_t orig_len;
2003
2004 // handle hidden AVPs
2005 if (!*config->l2tpsecret)
2006 {
2007 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2008 fatal = flags;
2009 result = 2; // general error
2010 error = 6; // generic vendor-specific error
2011 msg = "secret not specified";
2012 continue;
2013 }
2014 if (!session[s].random_vector_length)
2015 {
2016 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2017 fatal = flags;
2018 result = 2; // general error
2019 error = 6; // generic
2020 msg = "no random vector";
2021 continue;
2022 }
2023 if (n < 8)
2024 {
2025 LOG(2, s, t, "Short hidden AVP.\n");
2026 fatal = flags;
2027 result = 2; // general error
2028 error = 2; // length is wrong
2029 msg = 0;
2030 continue;
2031 }
2032
2033 LOG(4, s, t, "Hidden AVP\n");
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\n", mtype, avp_name(mtype), n);
2056 switch (mtype)
2057 {
2058 case 0: // message type
2059 message = ntohs(*(uint16_t *) b);
2060 mandatory = flags & 0x80;
2061 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_type(message));
2062 break;
2063 case 1: // result code
2064 {
2065 uint16_t rescode = ntohs(*(uint16_t *) b);
2066 const char* resdesc = "(unknown)";
2067 if (message == 4)
2068 { /* StopCCN */
2069 resdesc = stopccn_result_code(rescode);
2070 }
2071 else if (message == 14)
2072 { /* CDN */
2073 resdesc = cdn_result_code(rescode);
2074 }
2075
2076 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2077 if (n >= 4)
2078 {
2079 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2080 LOG(4, s, t, " Error Code %d: %s\n", errcode, error_code(errcode));
2081 }
2082 if (n > 4)
2083 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2084
2085 break;
2086 }
2087 break;
2088 case 2: // protocol version
2089 {
2090 version = ntohs(*(uint16_t *) (b));
2091 LOG(4, s, t, " Protocol version = %d\n", version);
2092 if (version && version != 0x0100)
2093 { // allow 0.0 and 1.0
2094 LOG(1, s, t, " Bad protocol version %04X\n", version);
2095 fatal = flags;
2096 result = 5; // unspported protocol version
2097 error = 0x0100; // supported version
2098 msg = 0;
2099 continue; // next
2100 }
2101 }
2102 break;
2103 case 3: // framing capabilities
2104 // LOG(4, s, t, "Framing capabilities\n");
2105 break;
2106 case 4: // bearer capabilities
2107 // LOG(4, s, t, "Bearer capabilities\n");
2108 break;
2109 case 5: // tie breaker
2110 // We never open tunnels, so we don't care about tie breakers
2111 // LOG(4, s, t, "Tie breaker\n");
2112 continue;
2113 case 6: // firmware revision
2114 // LOG(4, s, t, "Firmware revision\n");
2115 break;
2116 case 7: // host name
2117 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2118 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2119 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2120 // TBA - to send to RADIUS
2121 break;
2122 case 8: // vendor name
2123 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2124 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2125 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2126 break;
2127 case 9: // assigned tunnel
2128 tunnel[t].far = ntohs(*(uint16_t *) (b));
2129 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2130 break;
2131 case 10: // rx window
2132 tunnel[t].window = ntohs(*(uint16_t *) (b));
2133 if (!tunnel[t].window)
2134 tunnel[t].window = 1; // window of 0 is silly
2135 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2136 break;
2137 case 11: // Challenge
2138 {
2139 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2140 build_chap_response(b, 2, n, &chapresponse);
2141 }
2142 break;
2143 case 13: // Response
2144 // Why did they send a response? We never challenge.
2145 LOG(2, s, t, " received unexpected challenge response\n");
2146 break;
2147
2148 case 14: // assigned session
2149 asession = session[s].far = ntohs(*(uint16_t *) (b));
2150 LOG(4, s, t, " assigned session = %d\n", asession);
2151 break;
2152 case 15: // call serial number
2153 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2154 break;
2155 case 18: // bearer type
2156 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2157 // TBA - for RADIUS
2158 break;
2159 case 19: // framing type
2160 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2161 // TBA
2162 break;
2163 case 21: // called number
2164 memset(called, 0, sizeof(called));
2165 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2166 LOG(4, s, t, " Called <%s>\n", called);
2167 break;
2168 case 22: // calling number
2169 memset(calling, 0, sizeof(calling));
2170 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2171 LOG(4, s, t, " Calling <%s>\n", calling);
2172 break;
2173 case 23: // subtype
2174 break;
2175 case 24: // tx connect speed
2176 if (n == 4)
2177 {
2178 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2179 }
2180 else
2181 {
2182 // AS5300s send connect speed as a string
2183 char tmp[30];
2184 memset(tmp, 0, sizeof(tmp));
2185 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2186 session[s].tx_connect_speed = atol(tmp);
2187 }
2188 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2189 break;
2190 case 38: // rx connect speed
2191 if (n == 4)
2192 {
2193 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2194 }
2195 else
2196 {
2197 // AS5300s send connect speed as a string
2198 char tmp[30];
2199 memset(tmp, 0, sizeof(tmp));
2200 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2201 session[s].rx_connect_speed = atol(tmp);
2202 }
2203 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2204 break;
2205 case 25: // Physical Channel ID
2206 {
2207 uint32_t tmp = ntohl(*(uint32_t *) b);
2208 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2209 break;
2210 }
2211 case 29: // Proxy Authentication Type
2212 {
2213 uint16_t atype = ntohs(*(uint16_t *)b);
2214 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
2215 if (atype == 2)
2216 authtype = AUTHCHAP;
2217 else if (atype == 3)
2218 authtype = AUTHPAP;
2219
2220 break;
2221 }
2222 case 30: // Proxy Authentication Name
2223 {
2224 char authname[64];
2225 memset(authname, 0, sizeof(authname));
2226 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2227 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2228 authname);
2229 break;
2230 }
2231 case 31: // Proxy Authentication Challenge
2232 {
2233 LOG(4, s, t, " Proxy Auth Challenge\n");
2234 if (sess_local[s].radius)
2235 memcpy(radius[sess_local[s].radius].auth, b, 16);
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 if (sess_local[s].radius)
2243 radius[sess_local[s].radius].id = authid;
2244 break;
2245 }
2246 case 33: // Proxy Authentication Response
2247 LOG(4, s, t, " Proxy Auth Response\n");
2248 break;
2249 case 27: // last sent lcp
2250 { // find magic number
2251 uint8_t *p = b, *e = p + n;
2252 while (p + 1 < e && p[1] && p + p[1] <= e)
2253 {
2254 if (*p == 5 && p[1] == 6) // Magic-Number
2255 amagic = ntohl(*(uint32_t *) (p + 2));
2256 else if (*p == 3 && p[1] == 4 && *(uint16_t *) (p + 2) == htons(PPPPAP)) // Authentication-Protocol (PAP)
2257 authtype = AUTHPAP;
2258 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol (CHAP)
2259 authtype = AUTHCHAP;
2260 else if (*p == 7) // Protocol-Field-Compression
2261 aflags |= SESSIONPFC;
2262 else if (*p == 8) // Address-and-Control-Field-Compression
2263 aflags |= SESSIONACFC;
2264 p += p[1];
2265 }
2266 }
2267 break;
2268 case 28: // last recv lcp confreq
2269 break;
2270 case 26: // Initial Received LCP CONFREQ
2271 break;
2272 case 39: // seq required - we control it as an LNS anyway...
2273 break;
2274 case 36: // Random Vector
2275 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2276 memset(session[s].random_vector, 0, 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, t, 0); // 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 uint16_t r;
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 // make a RADIUS session
2351 if ((r = radiusnew(s)))
2352 {
2353 controlt *c = controlnew(11); // sending ICRP
2354 session[s].opened = time_now;
2355 session[s].tunnel = t;
2356 session[s].far = asession;
2357 session[s].last_packet = time_now;
2358 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2359 control16(c, 14, s, 1); // assigned session
2360 controladd(c, t, asession); // send the reply
2361
2362 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
2363 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2364 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2365 STAT(session_created);
2366 break;
2367 }
2368
2369
2370 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
2371 sessionclear(s);
2372 }
2373 else
2374 {
2375 STAT(session_overflow);
2376 LOG(1, 0, t, "No free sessions\n");
2377 }
2378
2379 {
2380 controlt *c = controlnew(14); // CDN
2381 if (main_quit == QUIT_SHUTDOWN)
2382 control16(c, 1, 2, 7); // try another
2383 else
2384 control16(c, 1, 4, 0); // temporary lack of resources
2385
2386 controladd(c, t, asession); // send the message
2387 }
2388 return;
2389 case 11: // ICRP
2390 // TBA
2391 break;
2392 case 12: // ICCN
2393 if (amagic == 0) amagic = time_now;
2394 session[s].magic = amagic; // set magic number
2395 session[s].l2tp_flags = aflags; // set flags received
2396 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
2397 controlnull(t); // ack
2398 // proxy authentication type is not supported
2399 if (!(config->radius_authtypes & authtype))
2400 authtype = config->radius_authprefer;
2401
2402 // start LCP
2403 sendlcp(t, s, authtype);
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(t, s, 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(t, s, 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(t, s, 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(t, s, p, l);
2494 }
2495 else if (prot == PPPIPV6CP)
2496 {
2497 if (config->ipv6_prefix.s6_addr[0] > 0)
2498 {
2499 session[s].last_packet = time_now;
2500 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2501 processipv6cp(t, s, p, l);
2502 }
2503 else
2504 {
2505 LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
2506 }
2507 }
2508 else if (prot == PPPCCP)
2509 {
2510 session[s].last_packet = time_now;
2511 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2512 processccp(t, s, p, l);
2513 }
2514 else if (prot == PPPIP)
2515 {
2516 if (session[s].die)
2517 {
2518 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2519 return; // closing session, PPP not processed
2520 }
2521
2522 session[s].last_packet = time_now;
2523 if (session[s].walled_garden && !config->cluster_iam_master)
2524 {
2525 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2526 return;
2527 }
2528
2529 processipin(t, s, p, l);
2530 }
2531 else if (prot == PPPIPV6)
2532 {
2533 if (!config->ipv6_prefix.s6_addr[0] > 0)
2534 {
2535 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2536 return;
2537 }
2538 if (session[s].die)
2539 {
2540 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2541 return; // closing session, PPP not processed
2542 }
2543
2544 session[s].last_packet = time_now;
2545 if (session[s].walled_garden && !config->cluster_iam_master)
2546 {
2547 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2548 return;
2549 }
2550
2551 processipv6in(t, s, p, l);
2552 }
2553 else
2554 {
2555 STAT(tunnel_rx_errors);
2556 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2557 }
2558 }
2559 }
2560
2561 // read and process packet on tun
2562 static void processtun(uint8_t * buf, int len)
2563 {
2564 LOG_HEX(5, "Receive TUN Data", buf, len);
2565 STAT(tun_rx_packets);
2566 INC_STAT(tun_rx_bytes, len);
2567
2568 CSTAT(processtun);
2569
2570 eth_rx_pkt++;
2571 eth_rx += len;
2572 if (len < 22)
2573 {
2574 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2575 STAT(tun_rx_errors);
2576 return;
2577 }
2578
2579 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2580 processipout(buf, len);
2581 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2582 && config->ipv6_prefix.s6_addr[0] > 0)
2583 processipv6out(buf, len);
2584
2585 // Else discard.
2586 }
2587
2588 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2589 // that we look at the whole of the tunnel, radius and session tables
2590 // every second
2591 static void regular_cleanups(double period)
2592 {
2593 // Next tunnel, radius and session to check for actions on.
2594 static tunnelidt t = 0;
2595 static int r = 0;
2596 static sessionidt s = 0;
2597
2598 int t_actions = 0;
2599 int r_actions = 0;
2600 int s_actions = 0;
2601
2602 int t_slice;
2603 int r_slice;
2604 int s_slice;
2605
2606 int i;
2607 int a;
2608
2609 // divide up tables into slices based on the last run
2610 t_slice = config->cluster_highest_tunnelid * period;
2611 r_slice = (MAXRADIUS - 1) * period;
2612 s_slice = config->cluster_highest_sessionid * period;
2613
2614 if (t_slice < 1)
2615 t_slice = 1;
2616 else if (t_slice > config->cluster_highest_tunnelid)
2617 t_slice = config->cluster_highest_tunnelid;
2618
2619 if (r_slice < 1)
2620 r_slice = 1;
2621 else if (r_slice > (MAXRADIUS - 1))
2622 r_slice = MAXRADIUS - 1;
2623
2624 if (s_slice < 1)
2625 s_slice = 1;
2626 else if (s_slice > config->cluster_highest_sessionid)
2627 s_slice = config->cluster_highest_sessionid;
2628
2629 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2630
2631 for (i = 0; i < t_slice; i++)
2632 {
2633 t++;
2634 if (t > config->cluster_highest_tunnelid)
2635 t = 1;
2636
2637 // check for expired tunnels
2638 if (tunnel[t].die && tunnel[t].die <= TIME)
2639 {
2640 STAT(tunnel_timeout);
2641 tunnelkill(t, "Expired");
2642 t_actions++;
2643 continue;
2644 }
2645 // check for message resend
2646 if (tunnel[t].retry && tunnel[t].controlc)
2647 {
2648 // resend pending messages as timeout on reply
2649 if (tunnel[t].retry <= TIME)
2650 {
2651 controlt *c = tunnel[t].controls;
2652 uint8_t w = tunnel[t].window;
2653 tunnel[t].try++; // another try
2654 if (tunnel[t].try > 5)
2655 tunnelkill(t, "Timeout on control message"); // game over
2656 else
2657 while (c && w--)
2658 {
2659 tunnelsend(c->buf, c->length, t);
2660 c = c->next;
2661 }
2662
2663 t_actions++;
2664 }
2665 }
2666 // Send hello
2667 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2668 {
2669 controlt *c = controlnew(6); // sending HELLO
2670 controladd(c, t, 0); // send the message
2671 LOG(3, 0, t, "Sending HELLO message\n");
2672 t_actions++;
2673 }
2674
2675 // Check for tunnel changes requested from the CLI
2676 if ((a = cli_tunnel_actions[t].action))
2677 {
2678 cli_tunnel_actions[t].action = 0;
2679 if (a & CLI_TUN_KILL)
2680 {
2681 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2682 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2683 t_actions++;
2684 }
2685 }
2686 }
2687
2688 for (i = 0; i < r_slice; i++)
2689 {
2690 r++;
2691 if (r >= MAXRADIUS)
2692 r = 1;
2693
2694 if (!radius[r].state)
2695 continue;
2696
2697 if (radius[r].retry <= TIME)
2698 {
2699 radiusretry(r);
2700 r_actions++;
2701 }
2702 }
2703
2704 for (i = 0; i < s_slice; i++)
2705 {
2706 s++;
2707 if (s > config->cluster_highest_sessionid)
2708 s = 1;
2709
2710 if (!session[s].opened) // Session isn't in use
2711 continue;
2712
2713 // check for expired sessions
2714 if (session[s].die)
2715 {
2716 if (session[s].die <= TIME)
2717 {
2718 sessionkill(s, "Expired");
2719 s_actions++;
2720 }
2721 continue;
2722 }
2723
2724 if (session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2725 {
2726 // IPCP has not completed yet. Resend
2727 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2728 sendipcp(session[s].tunnel, s);
2729 s_actions++;
2730 }
2731
2732 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2733 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2734 {
2735 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2736 STAT(session_timeout);
2737 s_actions++;
2738 continue;
2739 }
2740
2741 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2742 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2743 {
2744 uint8_t b[MAXCONTROL] = {0};
2745
2746 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2747 if (!q) continue;
2748
2749 *q = EchoReq;
2750 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2751 *(uint16_t *)(q + 2) = htons(8); // Length
2752 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2753
2754 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2755 (int)(time_now - session[s].last_packet));
2756 tunnelsend(b, 24, session[s].tunnel); // send it
2757 s_actions++;
2758 }
2759
2760 // Check for actions requested from the CLI
2761 if ((a = cli_session_actions[s].action))
2762 {
2763 int send = 0;
2764
2765 cli_session_actions[s].action = 0;
2766 if (a & CLI_SESS_KILL)
2767 {
2768 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2769 sessionshutdown(s, "Requested by administrator.", 3, 0);
2770 a = 0; // dead, no need to check for other actions
2771 s_actions++;
2772 }
2773
2774 if (a & CLI_SESS_NOSNOOP)
2775 {
2776 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2777 session[s].snoop_ip = 0;
2778 session[s].snoop_port = 0;
2779 s_actions++;
2780 send++;
2781 }
2782 else if (a & CLI_SESS_SNOOP)
2783 {
2784 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2785 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2786 cli_session_actions[s].snoop_port);
2787
2788 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2789 session[s].snoop_port = cli_session_actions[s].snoop_port;
2790 s_actions++;
2791 send++;
2792 }
2793
2794 if (a & CLI_SESS_NOTHROTTLE)
2795 {
2796 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2797 throttle_session(s, 0, 0);
2798 s_actions++;
2799 send++;
2800 }
2801 else if (a & CLI_SESS_THROTTLE)
2802 {
2803 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2804 cli_session_actions[s].throttle_in,
2805 cli_session_actions[s].throttle_out);
2806
2807 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2808 s_actions++;
2809 send++;
2810 }
2811
2812 if (a & CLI_SESS_NOFILTER)
2813 {
2814 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2815 filter_session(s, 0, 0);
2816 s_actions++;
2817 send++;
2818 }
2819 else if (a & CLI_SESS_FILTER)
2820 {
2821 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2822 cli_session_actions[s].filter_in,
2823 cli_session_actions[s].filter_out);
2824
2825 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2826 s_actions++;
2827 send++;
2828 }
2829
2830 if (send)
2831 cluster_send_session(s);
2832 }
2833
2834 // RADIUS interim accounting
2835 if (config->radius_accounting && config->radius_interim > 0
2836 && session[s].ip && !session[s].walled_garden
2837 && !sess_local[s].radius // RADIUS already in progress
2838 && time_now - sess_local[s].last_interim >= config->radius_interim)
2839 {
2840 if (!(r = radiusnew(s)))
2841 {
2842 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2843 STAT(radius_overflow);
2844 continue;
2845 }
2846
2847 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2848 session[s].user, session[s].unique_id);
2849
2850 radiussend(r, RADIUSINTERIM);
2851 sess_local[s].last_interim = time_now;
2852 s_actions++;
2853 }
2854 }
2855
2856 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2857 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2858 }
2859
2860 //
2861 // Are we in the middle of a tunnel update, or radius
2862 // requests??
2863 //
2864 static int still_busy(void)
2865 {
2866 int i;
2867 static clockt last_talked = 0;
2868 static clockt start_busy_wait = 0;
2869
2870 if (!config->cluster_iam_master)
2871 {
2872 #ifdef BGP
2873 static time_t stopped_bgp = 0;
2874 if (bgp_configured)
2875 {
2876 if (!stopped_bgp)
2877 {
2878 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2879
2880 for (i = 0; i < BGP_NUM_PEERS; i++)
2881 if (bgp_peers[i].state == Established)
2882 bgp_stop(&bgp_peers[i]);
2883
2884 stopped_bgp = time_now;
2885
2886 // we don't want to become master
2887 cluster_send_ping(0);
2888
2889 return 1;
2890 }
2891
2892 if (time_now < (stopped_bgp + QUIT_DELAY))
2893 return 1;
2894 }
2895 #endif /* BGP */
2896
2897 return 0;
2898 }
2899
2900 if (main_quit == QUIT_SHUTDOWN)
2901 {
2902 static int dropped = 0;
2903 if (!dropped)
2904 {
2905 int i;
2906
2907 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
2908 for (i = 1; i < MAXTUNNEL; i++)
2909 if (tunnel[i].ip || tunnel[i].state)
2910 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
2911
2912 dropped = 1;
2913 }
2914 }
2915
2916 if (start_busy_wait == 0)
2917 start_busy_wait = TIME;
2918
2919 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2920 {
2921 if (!tunnel[i].controlc)
2922 continue;
2923
2924 if (last_talked != TIME)
2925 {
2926 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2927 last_talked = TIME;
2928 }
2929 return 1;
2930 }
2931
2932 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2933 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2934 {
2935 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2936 return 0;
2937 }
2938
2939 for (i = 1; i < MAXRADIUS; i++)
2940 {
2941 if (radius[i].state == RADIUSNULL)
2942 continue;
2943 if (radius[i].state == RADIUSWAIT)
2944 continue;
2945
2946 if (last_talked != TIME)
2947 {
2948 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2949 last_talked = TIME;
2950 }
2951 return 1;
2952 }
2953
2954 return 0;
2955 }
2956
2957 #ifdef HAVE_EPOLL
2958 # include <sys/epoll.h>
2959 #else
2960 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
2961 # include "fake_epoll.h"
2962 #endif
2963
2964 // the base set of fds polled: control, cli, udp, tun, cluster
2965 #define BASE_FDS 5
2966
2967 // additional polled fds
2968 #ifdef BGP
2969 # define EXTRA_FDS BGP_NUM_PEERS
2970 #else
2971 # define EXTRA_FDS 0
2972 #endif
2973
2974 // main loop - gets packets on tun or udp and processes them
2975 static void mainloop(void)
2976 {
2977 int i;
2978 uint8_t buf[65536];
2979 clockt next_cluster_ping = 0; // send initial ping immediately
2980 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
2981 int maxevent = sizeof(events)/sizeof(*events);
2982
2983 if ((epollfd = epoll_create(maxevent)) < 0)
2984 {
2985 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
2986 exit(1);
2987 }
2988
2989 LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2990 udpfd, tunfd, cluster_sockfd, controlfd);
2991
2992 /* setup our fds to poll for input */
2993 {
2994 static struct event_data d[BASE_FDS];
2995 struct epoll_event e;
2996
2997 e.events = EPOLLIN;
2998 i = 0;
2999
3000 d[i].type = FD_TYPE_CONTROL;
3001 e.data.ptr = &d[i++];
3002 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3003
3004 d[i].type = FD_TYPE_CLI;
3005 e.data.ptr = &d[i++];
3006 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3007
3008 d[i].type = FD_TYPE_UDP;
3009 e.data.ptr = &d[i++];
3010 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3011
3012 d[i].type = FD_TYPE_TUN;
3013 e.data.ptr = &d[i++];
3014 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3015
3016 d[i].type = FD_TYPE_CLUSTER;
3017 e.data.ptr = &d[i++];
3018 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3019 }
3020
3021 #ifdef BGP
3022 signal(SIGPIPE, SIG_IGN);
3023 bgp_setup(config->as_number);
3024 if (config->bind_address)
3025 bgp_add_route(config->bind_address, 0xffffffff);
3026
3027 for (i = 0; i < BGP_NUM_PEERS; i++)
3028 {
3029 if (config->neighbour[i].name[0])
3030 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3031 config->neighbour[i].as, config->neighbour[i].keepalive,
3032 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3033 }
3034 #endif /* BGP */
3035
3036 while (!main_quit || still_busy())
3037 {
3038 int more = 0;
3039 int n;
3040
3041 if (config->reload_config)
3042 {
3043 // Update the config state based on config settings
3044 update_config();
3045 }
3046
3047 #ifdef BGP
3048 bgp_set_poll();
3049 #endif /* BGP */
3050
3051 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3052 STAT(select_called);
3053
3054 TIME = now(NULL);
3055 if (n < 0)
3056 {
3057 if (errno == EINTR ||
3058 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3059 continue;
3060
3061 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3062 break; // exit
3063 }
3064
3065 if (n)
3066 {
3067 struct sockaddr_in addr;
3068 int alen, c, s;
3069 int udp_ready = 0;
3070 int tun_ready = 0;
3071 int cluster_ready = 0;
3072 int udp_pkts = 0;
3073 int tun_pkts = 0;
3074 int cluster_pkts = 0;
3075 #ifdef BGP
3076 uint32_t bgp_events[BGP_NUM_PEERS];
3077 memset(bgp_events, 0, sizeof(bgp_events));
3078 #endif /* BGP */
3079
3080 for (c = n, i = 0; i < c; i++)
3081 {
3082 struct event_data *d = events[i].data.ptr;
3083 switch (d->type)
3084 {
3085 case FD_TYPE_CONTROL: // nsctl commands
3086 alen = sizeof(addr);
3087 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3088 n--;
3089 break;
3090
3091 case FD_TYPE_CLI: // CLI connections
3092 {
3093 int cli;
3094
3095 alen = sizeof(addr);
3096 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3097 {
3098 cli_do(cli);
3099 close(cli);
3100 }
3101 else
3102 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3103
3104 n--;
3105 break;
3106 }
3107
3108 // these are handled below, with multiple interleaved reads
3109 case FD_TYPE_UDP: udp_ready++; break;
3110 case FD_TYPE_TUN: tun_ready++; break;
3111 case FD_TYPE_CLUSTER: cluster_ready++; break;
3112
3113 case FD_TYPE_RADIUS: // RADIUS response
3114 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3115 if (s >= 0 && config->cluster_iam_master)
3116 processrad(buf, s, d->index);
3117
3118 n--;
3119 break;
3120
3121 #ifdef BGP
3122 case FD_TYPE_BGP:
3123 bgp_events[d->index] = events[i].events;
3124 n--;
3125 break;
3126 #endif /* BGP */
3127
3128 default:
3129 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3130 }
3131 }
3132
3133 #ifdef BGP
3134 bgp_process(bgp_events);
3135 #endif /* BGP */
3136
3137 for (c = 0; n && c < config->multi_read_count; c++)
3138 {
3139 // L2TP
3140 if (udp_ready)
3141 {
3142 alen = sizeof(addr);
3143 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3144 {
3145 processudp(buf, s, &addr);
3146 udp_pkts++;
3147 }
3148 else
3149 {
3150 udp_ready = 0;
3151 n--;
3152 }
3153 }
3154
3155 // incoming IP
3156 if (tun_ready)
3157 {
3158 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3159 {
3160 processtun(buf, s);
3161 tun_pkts++;
3162 }
3163 else
3164 {
3165 tun_ready = 0;
3166 n--;
3167 }
3168 }
3169
3170 // cluster
3171 if (cluster_ready)
3172 {
3173 alen = sizeof(addr);
3174 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3175 {
3176 processcluster(buf, s, addr.sin_addr.s_addr);
3177 cluster_pkts++;
3178 }
3179 else
3180 {
3181 cluster_ready = 0;
3182 n--;
3183 }
3184 }
3185 }
3186
3187 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3188 STAT(multi_read_used);
3189
3190 if (c >= config->multi_read_count)
3191 {
3192 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3193 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3194
3195 STAT(multi_read_exceeded);
3196 more++;
3197 }
3198 }
3199
3200 // Runs on every machine (master and slaves).
3201 if (next_cluster_ping <= TIME)
3202 {
3203 // Check to see which of the cluster is still alive..
3204
3205 cluster_send_ping(basetime); // Only does anything if we're a slave
3206 cluster_check_master(); // ditto.
3207
3208 cluster_heartbeat(); // Only does anything if we're a master.
3209 cluster_check_slaves(); // ditto.
3210
3211 master_update_counts(); // If we're a slave, send our byte counters to our master.
3212
3213 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3214 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3215 else
3216 next_cluster_ping = TIME + config->cluster_hb_interval;
3217 }
3218
3219 if (!config->cluster_iam_master)
3220 continue;
3221
3222 // Run token bucket filtering queue..
3223 // Only run it every 1/10th of a second.
3224 {
3225 static clockt last_run = 0;
3226 if (last_run != TIME)
3227 {
3228 last_run = TIME;
3229 tbf_run_timer();
3230 }
3231 }
3232
3233 // Handle timeouts, retries etc.
3234 {
3235 static double last_clean = 0;
3236 double this_clean;
3237 double diff;
3238
3239 TIME = now(&this_clean);
3240 diff = this_clean - last_clean;
3241
3242 // Run during idle time (after we've handled
3243 // all incoming packets) or every 1/10th sec
3244 if (!more || diff > 0.1)
3245 {
3246 regular_cleanups(diff);
3247 last_clean = this_clean;
3248 }
3249 }
3250
3251 if (*config->accounting_dir)
3252 {
3253 static clockt next_acct = 0;
3254 static clockt next_shut_acct = 0;
3255
3256 if (next_acct <= TIME)
3257 {
3258 // Dump accounting data
3259 next_acct = TIME + ACCT_TIME;
3260 next_shut_acct = TIME + ACCT_SHUT_TIME;
3261 dump_acct_info(1);
3262 }
3263 else if (next_shut_acct <= TIME)
3264 {
3265 // Dump accounting data for shutdown sessions
3266 next_shut_acct = TIME + ACCT_SHUT_TIME;
3267 if (shut_acct_n)
3268 dump_acct_info(0);
3269 }
3270 }
3271 }
3272
3273 // Are we the master and shutting down??
3274 if (config->cluster_iam_master)
3275 cluster_heartbeat(); // Flush any queued changes..
3276
3277 // Ok. Notify everyone we're shutting down. If we're
3278 // the master, this will force an election.
3279 cluster_send_ping(0);
3280
3281 //
3282 // Important!!! We MUST not process any packets past this point!
3283 LOG(1, 0, 0, "Shutdown complete\n");
3284 }
3285
3286 static void stripdomain(char *host)
3287 {
3288 char *p;
3289
3290 if ((p = strchr(host, '.')))
3291 {
3292 char *domain = 0;
3293 char _domain[1024];
3294
3295 // strip off domain
3296 FILE *resolv = fopen("/etc/resolv.conf", "r");
3297 if (resolv)
3298 {
3299 char buf[1024];
3300 char *b;
3301
3302 while (fgets(buf, sizeof(buf), resolv))
3303 {
3304 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3305 continue;
3306
3307 if (!isspace(buf[6]))
3308 continue;
3309
3310 b = buf + 7;
3311 while (isspace(*b)) b++;
3312
3313 if (*b)
3314 {
3315 char *d = b;
3316 while (*b && !isspace(*b)) b++;
3317 *b = 0;
3318 if (buf[0] == 'd') // domain is canonical
3319 {
3320 domain = d;
3321 break;
3322 }
3323
3324 // first search line
3325 if (!domain)
3326 {
3327 // hold, may be subsequent domain line
3328 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3329 domain = _domain;
3330 }
3331 }
3332 }
3333
3334 fclose(resolv);
3335 }
3336
3337 if (domain)
3338 {
3339 int hl = strlen(host);
3340 int dl = strlen(domain);
3341 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3342 host[hl -dl - 1] = 0;
3343 }
3344 else
3345 {
3346 *p = 0; // everything after first dot
3347 }
3348 }
3349 }
3350
3351 // Init data structures
3352 static void initdata(int optdebug, char *optconfig)
3353 {
3354 int i;
3355
3356 if (!(config = shared_malloc(sizeof(configt))))
3357 {
3358 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3359 exit(1);
3360 }
3361
3362 memset(config, 0, sizeof(configt));
3363 time(&config->start_time);
3364 strncpy(config->config_file, optconfig, strlen(optconfig));
3365 config->debug = optdebug;
3366 config->num_tbfs = MAXTBFS;
3367 config->rl_rate = 28; // 28kbps
3368 config->cluster_master_min_adv = 1;
3369 strcpy(config->random_device, RANDOMDEVICE);
3370
3371 log_stream = stderr;
3372
3373 #ifdef RINGBUFFER
3374 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3375 {
3376 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3377 exit(1);
3378 }
3379 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3380 #endif
3381
3382 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3383 {
3384 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3385 exit(1);
3386 }
3387 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3388 {
3389 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3390 exit(1);
3391 }
3392 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3393 {
3394 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3395 exit(1);
3396 }
3397
3398 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3399 {
3400 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3401 exit(1);
3402 }
3403
3404 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3405 {
3406 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3407 exit(1);
3408 }
3409
3410 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3411 {
3412 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3413 exit(1);
3414 }
3415
3416 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3417 {
3418 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3419 exit(1);
3420 }
3421 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3422
3423 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3424 {
3425 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3426 exit(1);
3427 }
3428 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3429
3430 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3431 {
3432 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3433 exit(1);
3434 }
3435 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3436
3437 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3438 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3439 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3440 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3441
3442 // Put all the sessions on the free list marked as undefined.
3443 for (i = 1; i < MAXSESSION; i++)
3444 {
3445 session[i].next = i + 1;
3446 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3447 }
3448 session[MAXSESSION - 1].next = 0;
3449 sessionfree = 1;
3450
3451 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3452 for (i = 1; i < MAXTUNNEL; i++)
3453 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3454
3455 if (!*hostname)
3456 {
3457 // Grab my hostname unless it's been specified
3458 gethostname(hostname, sizeof(hostname));
3459 stripdomain(hostname);
3460 }
3461
3462 _statistics->start_time = _statistics->last_reset = time(NULL);
3463
3464 #ifdef BGP
3465 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3466 {
3467 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3468 exit(1);
3469 }
3470 #endif /* BGP */
3471 }
3472
3473 static int assign_ip_address(sessionidt s)
3474 {
3475 uint32_t i;
3476 int best = -1;
3477 time_t best_time = time_now;
3478 char *u = session[s].user;
3479 char reuse = 0;
3480
3481
3482 CSTAT(assign_ip_address);
3483
3484 for (i = 1; i < ip_pool_size; i++)
3485 {
3486 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3487 continue;
3488
3489 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3490 {
3491 best = i;
3492 reuse = 1;
3493 break;
3494 }
3495
3496 if (ip_address_pool[i].last < best_time)
3497 {
3498 best = i;
3499 if (!(best_time = ip_address_pool[i].last))
3500 break; // never used, grab this one
3501 }
3502 }
3503
3504 if (best < 0)
3505 {
3506 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3507 return 0;
3508 }
3509
3510 session[s].ip = ip_address_pool[best].address;
3511 session[s].ip_pool_index = best;
3512 ip_address_pool[best].assigned = 1;
3513 ip_address_pool[best].last = time_now;
3514 ip_address_pool[best].session = s;
3515 if (session[s].walled_garden)
3516 /* Don't track addresses of users in walled garden (note: this
3517 means that their address isn't "sticky" even if they get
3518 un-gardened). */
3519 ip_address_pool[best].user[0] = 0;
3520 else
3521 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3522
3523 STAT(ip_allocated);
3524 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3525 reuse ? "Reusing" : "Allocating", best);
3526
3527 return 1;
3528 }
3529
3530 static void free_ip_address(sessionidt s)
3531 {
3532 int i = session[s].ip_pool_index;
3533
3534
3535 CSTAT(free_ip_address);
3536
3537 if (!session[s].ip)
3538 return; // what the?
3539
3540 if (i < 0) // Is this actually part of the ip pool?
3541 i = 0;
3542
3543 STAT(ip_freed);
3544 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3545 session[s].ip = 0;
3546 ip_address_pool[i].assigned = 0;
3547 ip_address_pool[i].session = 0;
3548 ip_address_pool[i].last = time_now;
3549 }
3550
3551 //
3552 // Fsck the address pool against the session table.
3553 // Normally only called when we become a master.
3554 //
3555 // This isn't perfect: We aren't keep tracking of which
3556 // users used to have an IP address.
3557 //
3558 void rebuild_address_pool(void)
3559 {
3560 int i;
3561
3562 //
3563 // Zero the IP pool allocation, and build
3564 // a map from IP address to pool index.
3565 for (i = 1; i < MAXIPPOOL; ++i)
3566 {
3567 ip_address_pool[i].assigned = 0;
3568 ip_address_pool[i].session = 0;
3569 if (!ip_address_pool[i].address)
3570 continue;
3571
3572 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3573 }
3574
3575 for (i = 0; i < MAXSESSION; ++i)
3576 {
3577 int ipid;
3578 if (!(session[i].opened && session[i].ip))
3579 continue;
3580
3581 ipid = - lookup_ipmap(htonl(session[i].ip));
3582
3583 if (session[i].ip_pool_index < 0)
3584 {
3585 // Not allocated out of the pool.
3586 if (ipid < 1) // Not found in the pool either? good.
3587 continue;
3588
3589 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3590 i, fmtaddr(session[i].ip, 0), ipid);
3591
3592 // Fall through and process it as part of the pool.
3593 }
3594
3595
3596 if (ipid > MAXIPPOOL || ipid < 0)
3597 {
3598 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3599 ipid = -1;
3600 session[i].ip_pool_index = ipid;
3601 continue;
3602 }
3603
3604 ip_address_pool[ipid].assigned = 1;
3605 ip_address_pool[ipid].session = i;
3606 ip_address_pool[ipid].last = time_now;
3607 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3608 session[i].ip_pool_index = ipid;
3609 cache_ipmap(session[i].ip, i); // Fix the ip map.
3610 }
3611 }
3612
3613 //
3614 // Fix the address pool to match a changed session.
3615 // (usually when the master sends us an update).
3616 static void fix_address_pool(int sid)
3617 {
3618 int ipid;
3619
3620 ipid = session[sid].ip_pool_index;
3621
3622 if (ipid > ip_pool_size)
3623 return; // Ignore it. rebuild_address_pool will fix it up.
3624
3625 if (ip_address_pool[ipid].address != session[sid].ip)
3626 return; // Just ignore it. rebuild_address_pool will take care of it.
3627
3628 ip_address_pool[ipid].assigned = 1;
3629 ip_address_pool[ipid].session = sid;
3630 ip_address_pool[ipid].last = time_now;
3631 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3632 }
3633
3634 //
3635 // Add a block of addresses to the IP pool to hand out.
3636 //
3637 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3638 {
3639 int i;
3640 if (mask == 0)
3641 mask = 0xffffffff; // Host route only.
3642
3643 addr &= mask;
3644
3645 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3646 return ;
3647
3648 for (i = addr ;(i & mask) == addr; ++i)
3649 {
3650 if ((i & 0xff) == 0 || (i&0xff) == 255)
3651 continue; // Skip 0 and broadcast addresses.
3652
3653 ip_address_pool[ip_pool_size].address = i;
3654 ip_address_pool[ip_pool_size].assigned = 0;
3655 ++ip_pool_size;
3656 if (ip_pool_size >= MAXIPPOOL)
3657 {
3658 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3659 return;
3660 }
3661 }
3662 }
3663
3664 // Initialize the IP address pool
3665 static void initippool()
3666 {
3667 FILE *f;
3668 char *p;
3669 char buf[4096];
3670 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3671
3672 if (!(f = fopen(IPPOOLFILE, "r")))
3673 {
3674 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3675 exit(1);
3676 }
3677
3678 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3679 {
3680 char *pool = buf;
3681 buf[4095] = 0; // Force it to be zero terminated/
3682
3683 if (*buf == '#' || *buf == '\n')
3684 continue; // Skip comments / blank lines
3685 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3686 if ((p = (char *)strchr(buf, ':')))
3687 {
3688 in_addr_t src;
3689 *p = '\0';
3690 src = inet_addr(buf);
3691 if (src == INADDR_NONE)
3692 {
3693 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3694 exit(1);
3695 }
3696 // This entry is for a specific IP only
3697 if (src != config->bind_address)
3698 continue;
3699 *p = ':';
3700 pool = p+1;
3701 }
3702 if ((p = (char *)strchr(pool, '/')))
3703 {
3704 // It's a range
3705 int numbits = 0;
3706 in_addr_t start = 0, mask = 0;
3707
3708 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3709 *p++ = 0;
3710 if (!*p || !(numbits = atoi(p)))
3711 {
3712 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3713 continue;
3714 }
3715 start = ntohl(inet_addr(pool));
3716 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3717
3718 // Add a static route for this pool
3719 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3720 fmtaddr(htonl(start), 0), 32 + mask);
3721
3722 routeset(0, start, mask, 0, 1);
3723
3724 add_to_ip_pool(start, mask);
3725 }
3726 else
3727 {
3728 // It's a single ip address
3729 add_to_ip_pool(inet_addr(pool), 0);
3730 }
3731 }
3732 fclose(f);
3733 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3734 }
3735
3736 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
3737 {
3738 struct sockaddr_in snoop_addr = {0};
3739 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3740 return;
3741
3742 snoop_addr.sin_family = AF_INET;
3743 snoop_addr.sin_addr.s_addr = destination;
3744 snoop_addr.sin_port = ntohs(port);
3745
3746 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3747 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3748 htons(snoop_addr.sin_port));
3749
3750 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3751 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3752
3753 STAT(packets_snooped);
3754 }
3755
3756 static int dump_session(FILE **f, sessiont *s)
3757 {
3758 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3759 return 1;
3760
3761 if (!*f)
3762 {
3763 char filename[1024];
3764 char timestr[64];
3765 time_t now = time(NULL);
3766
3767 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3768 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3769
3770 if (!(*f = fopen(filename, "w")))
3771 {
3772 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3773 return 0;
3774 }
3775
3776 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3777 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3778 "# host: %s\n"
3779 "# endpoint: %s\n"
3780 "# time: %ld\n"
3781 "# uptime: %ld\n"
3782 "# format: username ip qos uptxoctets downrxoctets\n",
3783 hostname,
3784 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3785 now,
3786 now - basetime);
3787 }
3788
3789 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3790 fprintf(*f, "%s %s %d %u %u\n",
3791 s->user, // username
3792 fmtaddr(htonl(s->ip), 0), // ip
3793 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3794 (uint32_t) s->cin_delta, // uptxoctets
3795 (uint32_t) s->cout_delta); // downrxoctets
3796
3797 s->cin_delta = s->cout_delta = 0;
3798
3799 return 1;
3800 }
3801
3802 static void dump_acct_info(int all)
3803 {
3804 int i;
3805 FILE *f = NULL;
3806
3807
3808 CSTAT(dump_acct_info);
3809
3810 if (shut_acct_n)
3811 {
3812 for (i = 0; i < shut_acct_n; i++)
3813 dump_session(&f, &shut_acct[i]);
3814
3815 shut_acct_n = 0;
3816 }
3817
3818 if (all)
3819 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3820 dump_session(&f, &session[i]);
3821
3822 if (f)
3823 fclose(f);
3824 }
3825
3826 // Main program
3827 int main(int argc, char *argv[])
3828 {
3829 int i;
3830 int optdebug = 0;
3831 char *optconfig = CONFIGFILE;
3832
3833 time(&basetime); // start clock
3834
3835 // scan args
3836 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3837 {
3838 switch (i)
3839 {
3840 case 'd':
3841 if (fork()) exit(0);
3842 setsid();
3843 freopen("/dev/null", "r", stdin);
3844 freopen("/dev/null", "w", stdout);
3845 freopen("/dev/null", "w", stderr);
3846 break;
3847 case 'v':
3848 optdebug++;
3849 break;
3850 case 'c':
3851 optconfig = optarg;
3852 break;
3853 case 'h':
3854 snprintf(hostname, sizeof(hostname), "%s", optarg);
3855 break;
3856 default:
3857 printf("Args are:\n"
3858 "\t-d\t\tDetach from terminal\n"
3859 "\t-c <file>\tConfig file\n"
3860 "\t-h <hostname>\tForce hostname\n"
3861 "\t-v\t\tDebug\n");
3862
3863 return (0);
3864 break;
3865 }
3866 }
3867
3868 // Start the timer routine off
3869 time(&time_now);
3870 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3871 signal(SIGALRM, sigalrm_handler);
3872 siginterrupt(SIGALRM, 0);
3873
3874 initplugins();
3875 initdata(optdebug, optconfig);
3876
3877 init_cli(hostname);
3878 read_config_file();
3879 init_tbf(config->num_tbfs);
3880
3881 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3882 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3883 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3884 {
3885 struct rlimit rlim;
3886 rlim.rlim_cur = RLIM_INFINITY;
3887 rlim.rlim_max = RLIM_INFINITY;
3888 // Remove the maximum core size
3889 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3890 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3891
3892 // Make core dumps go to /tmp
3893 chdir("/tmp");
3894 }
3895
3896 if (config->scheduler_fifo)
3897 {
3898 int ret;
3899 struct sched_param params = {0};
3900 params.sched_priority = 1;
3901
3902 if (get_nprocs() < 2)
3903 {
3904 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3905 config->scheduler_fifo = 0;
3906 }
3907 else
3908 {
3909 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3910 {
3911 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3912 }
3913 else
3914 {
3915 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3916 config->scheduler_fifo = 0;
3917 }
3918 }
3919 }
3920
3921 /* Set up the cluster communications port. */
3922 if (cluster_init() < 0)
3923 exit(1);
3924
3925 inittun();
3926 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3927
3928 initudp();
3929 initrad();
3930 initippool();
3931
3932 signal(SIGHUP, sighup_handler);
3933 signal(SIGCHLD, sigchild_handler);
3934 signal(SIGTERM, shutdown_handler);
3935 signal(SIGINT, shutdown_handler);
3936 signal(SIGQUIT, shutdown_handler);
3937
3938 // Prevent us from getting paged out
3939 if (config->lock_pages)
3940 {
3941 if (!mlockall(MCL_CURRENT))
3942 LOG(1, 0, 0, "Locking pages into memory\n");
3943 else
3944 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3945 }
3946
3947 alarm(1);
3948
3949 // Drop privileges here
3950 if (config->target_uid > 0 && geteuid() == 0)
3951 setuid(config->target_uid);
3952
3953 mainloop();
3954
3955 /* remove plugins (so cleanup code gets run) */
3956 plugins_done();
3957
3958 // Remove the PID file if we wrote it
3959 if (config->wrote_pid && *config->pid_file == '/')
3960 unlink(config->pid_file);
3961
3962 /* kill CLI children */
3963 signal(SIGTERM, SIG_IGN);
3964 kill(0, SIGTERM);
3965 return 0;
3966 }
3967
3968 static void sighup_handler(int sig)
3969 {
3970 if (log_stream)
3971 {
3972 if (log_stream != stderr)
3973 fclose(log_stream);
3974
3975 log_stream = NULL;
3976 }
3977
3978 read_config_file();
3979 }
3980
3981 static void sigalrm_handler(int sig)
3982 {
3983 // Log current traffic stats
3984
3985 snprintf(config->bandwidth, sizeof(config->bandwidth),
3986 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3987 (udp_rx / 1024.0 / 1024.0 * 8),
3988 (eth_tx / 1024.0 / 1024.0 * 8),
3989 (eth_rx / 1024.0 / 1024.0 * 8),
3990 (udp_tx / 1024.0 / 1024.0 * 8),
3991 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3992 udp_rx_pkt, eth_rx_pkt);
3993
3994 udp_tx = udp_rx = 0;
3995 udp_rx_pkt = eth_rx_pkt = 0;
3996 eth_tx = eth_rx = 0;
3997
3998 if (config->dump_speed)
3999 printf("%s\n", config->bandwidth);
4000
4001 // Update the internal time counter
4002 time(&time_now);
4003 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4004 alarm(1);
4005
4006 {
4007 // Run timer hooks
4008 struct param_timer p = { time_now };
4009 run_plugins(PLUGIN_TIMER, &p);
4010 }
4011
4012 }
4013
4014 static void shutdown_handler(int sig)
4015 {
4016 LOG(1, 0, 0, "Shutting down\n");
4017 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4018 }
4019
4020 static void sigchild_handler(int sig)
4021 {
4022 while (waitpid(-1, NULL, WNOHANG) > 0)
4023 ;
4024 }
4025
4026 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
4027 {
4028 MD5_CTX ctx;
4029 *challenge_response = NULL;
4030
4031 if (!*config->l2tpsecret)
4032 {
4033 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4034 return;
4035 }
4036
4037 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4038
4039 *challenge_response = (char *)calloc(17, 1);
4040
4041 MD5Init(&ctx);
4042 MD5Update(&ctx, &id, 1);
4043 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4044 MD5Update(&ctx, challenge, challenge_length);
4045 MD5Final(*challenge_response, &ctx);
4046
4047 return;
4048 }
4049
4050 static int facility_value(char *name)
4051 {
4052 int i;
4053 for (i = 0; facilitynames[i].c_name; i++)
4054 {
4055 if (strcmp(facilitynames[i].c_name, name) == 0)
4056 return facilitynames[i].c_val;
4057 }
4058 return 0;
4059 }
4060
4061 static void update_config()
4062 {
4063 int i;
4064 char *p;
4065 static int timeout = 0;
4066 static int interval = 0;
4067
4068 // Update logging
4069 closelog();
4070 syslog_log = 0;
4071 if (log_stream)
4072 {
4073 if (log_stream != stderr)
4074 fclose(log_stream);
4075
4076 log_stream = NULL;
4077 }
4078
4079 if (*config->log_filename)
4080 {
4081 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4082 {
4083 char *p = config->log_filename + 7;
4084 if (*p)
4085 {
4086 openlog("l2tpns", LOG_PID, facility_value(p));
4087 syslog_log = 1;
4088 }
4089 }
4090 else if (strchr(config->log_filename, '/') == config->log_filename)
4091 {
4092 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4093 {
4094 fseek(log_stream, 0, SEEK_END);
4095 setbuf(log_stream, NULL);
4096 }
4097 else
4098 {
4099 log_stream = stderr;
4100 setbuf(log_stream, NULL);
4101 }
4102 }
4103 }
4104 else
4105 {
4106 log_stream = stderr;
4107 setbuf(log_stream, NULL);
4108 }
4109
4110 // Update radius
4111 config->numradiusservers = 0;
4112 for (i = 0; i < MAXRADSERVER; i++)
4113 if (config->radiusserver[i])
4114 {
4115 config->numradiusservers++;
4116 // Set radius port: if not set, take the port from the
4117 // first radius server. For the first radius server,
4118 // take the #defined default value from l2tpns.h
4119
4120 // test twice, In case someone works with
4121 // a secondary radius server without defining
4122 // a primary one, this will work even then.
4123 if (i > 0 && !config->radiusport[i])
4124 config->radiusport[i] = config->radiusport[i-1];
4125 if (!config->radiusport[i])
4126 config->radiusport[i] = RADPORT;
4127 }
4128
4129 if (!config->numradiusservers)
4130 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4131
4132 // parse radius_authtypes_s
4133 config->radius_authtypes = config->radius_authprefer = 0;
4134 p = config->radius_authtypes_s;
4135 while (p && *p)
4136 {
4137 char *s = strpbrk(p, " \t,");
4138 int type = 0;
4139
4140 if (s)
4141 {
4142 *s++ = 0;
4143 while (*s == ' ' || *s == '\t')
4144 s++;
4145
4146 if (!*s)
4147 s = 0;
4148 }
4149
4150 if (!strncasecmp("chap", p, strlen(p)))
4151 type = AUTHCHAP;
4152 else if (!strncasecmp("pap", p, strlen(p)))
4153 type = AUTHPAP;
4154 else
4155 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4156
4157 config->radius_authtypes |= type;
4158 if (!config->radius_authprefer)
4159 config->radius_authprefer = type;
4160
4161 p = s;
4162 }
4163
4164 if (!config->radius_authtypes)
4165 {
4166 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4167 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4168 }
4169
4170 // normalise radius_authtypes_s
4171 if (config->radius_authprefer == AUTHPAP)
4172 {
4173 strcpy(config->radius_authtypes_s, "pap");
4174 if (config->radius_authtypes & AUTHCHAP)
4175 strcat(config->radius_authtypes_s, ", chap");
4176 }
4177 else
4178 {
4179 strcpy(config->radius_authtypes_s, "chap");
4180 if (config->radius_authtypes & AUTHPAP)
4181 strcat(config->radius_authtypes_s, ", pap");
4182 }
4183
4184 // re-initialise the random number source
4185 initrandom(config->random_device);
4186
4187 // Update plugins
4188 for (i = 0; i < MAXPLUGINS; i++)
4189 {
4190 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4191 continue;
4192
4193 if (*config->plugins[i])
4194 {
4195 // Plugin added
4196 add_plugin(config->plugins[i]);
4197 }
4198 else if (*config->old_plugins[i])
4199 {
4200 // Plugin removed
4201 remove_plugin(config->old_plugins[i]);
4202 }
4203 }
4204
4205 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4206 if (!config->multi_read_count) config->multi_read_count = 10;
4207 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4208 if (!*config->cluster_interface)
4209 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4210
4211 if (!config->cluster_hb_interval)
4212 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4213
4214 if (!config->cluster_hb_timeout)
4215 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4216
4217 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4218 {
4219 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4220 // late, ensure we're sufficiently larger than that
4221 int t = 4 * config->cluster_hb_interval + 11;
4222
4223 if (config->cluster_hb_timeout < t)
4224 {
4225 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4226 config->cluster_hb_timeout = t;
4227 }
4228
4229 // Push timing changes to the slaves immediately if we're the master
4230 if (config->cluster_iam_master)
4231 cluster_heartbeat();
4232
4233 interval = config->cluster_hb_interval;
4234 timeout = config->cluster_hb_timeout;
4235 }
4236
4237 // Write PID file
4238 if (*config->pid_file == '/' && !config->wrote_pid)
4239 {
4240 FILE *f;
4241 if ((f = fopen(config->pid_file, "w")))
4242 {
4243 fprintf(f, "%d\n", getpid());
4244 fclose(f);
4245 config->wrote_pid = 1;
4246 }
4247 else
4248 {
4249 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4250 }
4251 }
4252
4253 config->reload_config = 0;
4254 }
4255
4256 static void read_config_file()
4257 {
4258 FILE *f;
4259
4260 if (!config->config_file) return;
4261 if (!(f = fopen(config->config_file, "r")))
4262 {
4263 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4264 return;
4265 }
4266
4267 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4268 cli_do_file(f);
4269 LOG(3, 0, 0, "Done reading config file\n");
4270 fclose(f);
4271 update_config();
4272 }
4273
4274 int sessionsetup(tunnelidt t, sessionidt s)
4275 {
4276 // A session now exists, set it up
4277 in_addr_t ip;
4278 char *user;
4279 sessionidt i;
4280 int r;
4281
4282 CSTAT(sessionsetup);
4283
4284 LOG(3, s, t, "Doing session setup for session\n");
4285
4286 if (!session[s].ip)
4287 {
4288 assign_ip_address(s);
4289 if (!session[s].ip)
4290 {
4291 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4292 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4293 return 0;
4294 }
4295 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4296 fmtaddr(htonl(session[s].ip), 0));
4297 }
4298
4299
4300 // Make sure this is right
4301 session[s].tunnel = t;
4302
4303 // zap old sessions with same IP and/or username
4304 // Don't kill gardened sessions - doing so leads to a DoS
4305 // from someone who doesn't need to know the password
4306 {
4307 ip = session[s].ip;
4308 user = session[s].user;
4309 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4310 {
4311 if (i == s) continue;
4312 if (!session[s].opened) continue;
4313 if (ip == session[i].ip)
4314 {
4315 sessionkill(i, "Duplicate IP address");
4316 continue;
4317 }
4318
4319 if (config->allow_duplicate_users) continue;
4320 if (session[s].walled_garden || session[i].walled_garden) continue;
4321 if (!strcasecmp(user, session[i].user))
4322 sessionkill(i, "Duplicate session for users");
4323 }
4324 }
4325
4326 {
4327 int routed = 0;
4328
4329 // Add the route for this session.
4330 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4331 {
4332 if ((session[s].ip & session[s].route[r].mask) ==
4333 (session[s].route[r].ip & session[s].route[r].mask))
4334 routed++;
4335
4336 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4337 }
4338
4339 // Static IPs need to be routed if not already
4340 // convered by a Framed-Route. Anything else is part
4341 // of the IP address pool and is already routed, it
4342 // just needs to be added to the IP cache.
4343 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4344 if (session[s].ip_pool_index == -1) // static ip
4345 {
4346 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4347 }
4348 else
4349 cache_ipmap(session[s].ip, s);
4350 }
4351
4352 if (!session[s].unique_id)
4353 {
4354 // did this session just finish radius?
4355 LOG(3, s, t, "Sending initial IPCP to client\n");
4356 sendipcp(t, s);
4357 session[s].unique_id = ++last_id;
4358 }
4359
4360 // Run the plugin's against this new session.
4361 {
4362 struct param_new_session data = { &tunnel[t], &session[s] };
4363 run_plugins(PLUGIN_NEW_SESSION, &data);
4364 }
4365
4366 // Allocate TBFs if throttled
4367 if (session[s].throttle_in || session[s].throttle_out)
4368 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4369
4370 session[s].last_packet = time_now;
4371
4372 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4373 fmtaddr(htonl(session[s].ip), 0),
4374 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4375
4376 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4377
4378 return 1; // RADIUS OK and IP allocated, done...
4379 }
4380
4381 //
4382 // This session just got dropped on us by the master or something.
4383 // Make sure our tables up up to date...
4384 //
4385 int load_session(sessionidt s, sessiont *new)
4386 {
4387 int i;
4388 int newip = 0;
4389
4390 // Sanity checks.
4391 if (new->ip_pool_index >= MAXIPPOOL ||
4392 new->tunnel >= MAXTUNNEL)
4393 {
4394 LOG(0, s, 0, "Strange session update received!\n");
4395 // FIXME! What to do here?
4396 return 0;
4397 }
4398
4399 //
4400 // Ok. All sanity checks passed. Now we're committed to
4401 // loading the new session.
4402 //
4403
4404 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4405
4406 // See if routes/ip cache need updating
4407 if (new->ip != session[s].ip)
4408 newip++;
4409
4410 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4411 if (new->route[i].ip != session[s].route[i].ip ||
4412 new->route[i].mask != session[s].route[i].mask)
4413 newip++;
4414
4415 // needs update
4416 if (newip)
4417 {
4418 int routed = 0;
4419
4420 // remove old routes...
4421 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4422 {
4423 if ((session[s].ip & session[s].route[i].mask) ==
4424 (session[s].route[i].ip & session[s].route[i].mask))
4425 routed++;
4426
4427 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4428 }
4429
4430 // ...ip
4431 if (session[s].ip)
4432 {
4433 if (session[s].ip_pool_index == -1) // static IP
4434 {
4435 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4436 }
4437 else // It's part of the IP pool, remove it manually.
4438 uncache_ipmap(session[s].ip);
4439 }
4440
4441 routed = 0;
4442
4443 // add new routes...
4444 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4445 {
4446 if ((new->ip & new->route[i].mask) ==
4447 (new->route[i].ip & new->route[i].mask))
4448 routed++;
4449
4450 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4451 }
4452
4453 // ...ip
4454 if (new->ip)
4455 {
4456 // If there's a new one, add it.
4457 if (new->ip_pool_index == -1)
4458 {
4459 if (!routed) routeset(s, new->ip, 0, 0, 1);
4460 }
4461 else
4462 cache_ipmap(new->ip, s);
4463 }
4464 }
4465
4466 // check v6 routing
4467 if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
4468 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4469
4470 // check filters
4471 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4472 {
4473 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4474 new->filter_in = 0;
4475 }
4476
4477 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4478 {
4479 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4480 new->filter_out = 0;
4481 }
4482
4483 if (new->filter_in != session[s].filter_in)
4484 {
4485 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4486 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4487 }
4488
4489 if (new->filter_out != session[s].filter_out)
4490 {
4491 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4492 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4493 }
4494
4495 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4496 // for walking the sessions to forward byte counts to the master.
4497 config->cluster_highest_sessionid = s;
4498
4499 // TEMP: old session struct used a uint32_t to define the throttle
4500 // speed for both up/down, new uses a uint16_t for each. Deal with
4501 // sessions from an old master for migration.
4502 if (new->throttle_out == 0 && new->tbf_out)
4503 new->throttle_out = new->throttle_in;
4504
4505 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4506
4507 // Do fixups into address pool.
4508 if (new->ip_pool_index != -1)
4509 fix_address_pool(s);
4510
4511 return 1;
4512 }
4513
4514 static void initplugins()
4515 {
4516 int i;
4517
4518 loaded_plugins = ll_init();
4519 // Initialize the plugins to nothing
4520 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4521 plugins[i] = ll_init();
4522 }
4523
4524 static void *open_plugin(char *plugin_name, int load)
4525 {
4526 char path[256] = "";
4527
4528 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4529 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4530 return dlopen(path, RTLD_NOW);
4531 }
4532
4533 // plugin callback to get a config value
4534 static void *getconfig(char *key, enum config_typet type)
4535 {
4536 int i;
4537
4538 for (i = 0; config_values[i].key; i++)
4539 {
4540 if (!strcmp(config_values[i].key, key))
4541 {
4542 if (config_values[i].type == type)
4543 return ((void *) config) + config_values[i].offset;
4544
4545 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4546 key, type, config_values[i].type);
4547
4548 return 0;
4549 }
4550 }
4551
4552 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4553 return 0;
4554 }
4555
4556 static int add_plugin(char *plugin_name)
4557 {
4558 static struct pluginfuncs funcs = {
4559 _log,
4560 _log_hex,
4561 fmtaddr,
4562 sessionbyuser,
4563 sessiontbysessionidt,
4564 sessionidtbysessiont,
4565 radiusnew,
4566 radiussend,
4567 getconfig,
4568 sessionshutdown,
4569 sessionkill,
4570 throttle_session,
4571 cluster_send_session,
4572 };
4573
4574 void *p = open_plugin(plugin_name, 1);
4575 int (*initfunc)(struct pluginfuncs *);
4576 int i;
4577
4578 if (!p)
4579 {
4580 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4581 return -1;
4582 }
4583
4584 if (ll_contains(loaded_plugins, p))
4585 {
4586 dlclose(p);
4587 return 0; // already loaded
4588 }
4589
4590 {
4591 int *v = dlsym(p, "plugin_api_version");
4592 if (!v || *v != PLUGIN_API_VERSION)
4593 {
4594 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4595 dlclose(p);
4596 return -1;
4597 }
4598 }
4599
4600 if ((initfunc = dlsym(p, "plugin_init")))
4601 {
4602 if (!initfunc(&funcs))
4603 {
4604 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4605 dlclose(p);
4606 return -1;
4607 }
4608 }
4609
4610 ll_push(loaded_plugins, p);
4611
4612 for (i = 0; i < max_plugin_functions; i++)
4613 {
4614 void *x;
4615 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4616 {
4617 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4618 ll_push(plugins[i], x);
4619 }
4620 }
4621
4622 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4623 return 1;
4624 }
4625
4626 static void run_plugin_done(void *plugin)
4627 {
4628 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4629
4630 if (donefunc)
4631 donefunc();
4632 }
4633
4634 static int remove_plugin(char *plugin_name)
4635 {
4636 void *p = open_plugin(plugin_name, 0);
4637 int loaded = 0;
4638
4639 if (!p)
4640 return -1;
4641
4642 if (ll_contains(loaded_plugins, p))
4643 {
4644 int i;
4645 for (i = 0; i < max_plugin_functions; i++)
4646 {
4647 void *x;
4648 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4649 ll_delete(plugins[i], x);
4650 }
4651
4652 ll_delete(loaded_plugins, p);
4653 run_plugin_done(p);
4654 loaded = 1;
4655 }
4656
4657 dlclose(p);
4658 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4659 return loaded;
4660 }
4661
4662 int run_plugins(int plugin_type, void *data)
4663 {
4664 int (*func)(void *data);
4665
4666 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4667 return PLUGIN_RET_ERROR;
4668
4669 ll_reset(plugins[plugin_type]);
4670 while ((func = ll_next(plugins[plugin_type])))
4671 {
4672 int r = func(data);
4673
4674 if (r != PLUGIN_RET_OK)
4675 return r; // stop here
4676 }
4677
4678 return PLUGIN_RET_OK;
4679 }
4680
4681 static void plugins_done()
4682 {
4683 void *p;
4684
4685 ll_reset(loaded_plugins);
4686 while ((p = ll_next(loaded_plugins)))
4687 run_plugin_done(p);
4688 }
4689
4690 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4691 {
4692 struct nsctl request;
4693 struct nsctl response;
4694 int type = unpack_control(&request, buf, len);
4695 int r;
4696 void *p;
4697
4698 if (log_stream && config->debug >= 4)
4699 {
4700 if (type < 0)
4701 {
4702 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4703 fmtaddr(addr->sin_addr.s_addr, 0), type);
4704 }
4705 else
4706 {
4707 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4708 dump_control(&request, log_stream);
4709 }
4710 }
4711
4712 switch (type)
4713 {
4714 case NSCTL_REQ_LOAD:
4715 if (request.argc != 1)
4716 {
4717 response.type = NSCTL_RES_ERR;
4718 response.argc = 1;
4719 response.argv[0] = "name of plugin required";
4720 }
4721 else if ((r = add_plugin(request.argv[0])) < 1)
4722 {
4723 response.type = NSCTL_RES_ERR;
4724 response.argc = 1;
4725 response.argv[0] = !r
4726 ? "plugin already loaded"
4727 : "error loading plugin";
4728 }
4729 else
4730 {
4731 response.type = NSCTL_RES_OK;
4732 response.argc = 0;
4733 }
4734
4735 break;
4736
4737 case NSCTL_REQ_UNLOAD:
4738 if (request.argc != 1)
4739 {
4740 response.type = NSCTL_RES_ERR;
4741 response.argc = 1;
4742 response.argv[0] = "name of plugin required";
4743 }
4744 else if ((r = remove_plugin(request.argv[0])) < 1)
4745 {
4746 response.type = NSCTL_RES_ERR;
4747 response.argc = 1;
4748 response.argv[0] = !r
4749 ? "plugin not loaded"
4750 : "plugin not found";
4751 }
4752 else
4753 {
4754 response.type = NSCTL_RES_OK;
4755 response.argc = 0;
4756 }
4757
4758 break;
4759
4760 case NSCTL_REQ_HELP:
4761 response.type = NSCTL_RES_OK;
4762 response.argc = 0;
4763
4764 ll_reset(loaded_plugins);
4765 while ((p = ll_next(loaded_plugins)))
4766 {
4767 char **help = dlsym(p, "plugin_control_help");
4768 while (response.argc < 0xff && help && *help)
4769 response.argv[response.argc++] = *help++;
4770 }
4771
4772 break;
4773
4774 case NSCTL_REQ_CONTROL:
4775 {
4776 struct param_control param = {
4777 config->cluster_iam_master,
4778 request.argc,
4779 request.argv,
4780 0,
4781 NULL,
4782 };
4783
4784 int r = run_plugins(PLUGIN_CONTROL, &param);
4785
4786 if (r == PLUGIN_RET_ERROR)
4787 {
4788 response.type = NSCTL_RES_ERR;
4789 response.argc = 1;
4790 response.argv[0] = param.additional
4791 ? param.additional
4792 : "error returned by plugin";
4793 }
4794 else if (r == PLUGIN_RET_NOTMASTER)
4795 {
4796 static char msg[] = "must be run on master: 000.000.000.000";
4797
4798 response.type = NSCTL_RES_ERR;
4799 response.argc = 1;
4800 if (config->cluster_master_address)
4801 {
4802 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4803 response.argv[0] = msg;
4804 }
4805 else
4806 {
4807 response.argv[0] = "must be run on master: none elected";
4808 }
4809 }
4810 else if (!(param.response & NSCTL_RESPONSE))
4811 {
4812 response.type = NSCTL_RES_ERR;
4813 response.argc = 1;
4814 response.argv[0] = param.response
4815 ? "unrecognised response value from plugin"
4816 : "unhandled action";
4817 }
4818 else
4819 {
4820 response.type = param.response;
4821 response.argc = 0;
4822 if (param.additional)
4823 {
4824 response.argc = 1;
4825 response.argv[0] = param.additional;
4826 }
4827 }
4828 }
4829
4830 break;
4831
4832 default:
4833 response.type = NSCTL_RES_ERR;
4834 response.argc = 1;
4835 response.argv[0] = "error unpacking control packet";
4836 }
4837
4838 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4839 if (!buf)
4840 {
4841 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4842 return;
4843 }
4844
4845 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4846 if (r > 0)
4847 {
4848 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4849 if (log_stream && config->debug >= 4)
4850 {
4851 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4852 dump_control(&response, log_stream);
4853 }
4854 }
4855 else
4856 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4857 fmtaddr(addr->sin_addr.s_addr, 0), r);
4858
4859 free(buf);
4860 }
4861
4862 static tunnelidt new_tunnel()
4863 {
4864 tunnelidt i;
4865 for (i = 1; i < MAXTUNNEL; i++)
4866 {
4867 if (tunnel[i].state == TUNNELFREE)
4868 {
4869 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4870 if (i > config->cluster_highest_tunnelid)
4871 config->cluster_highest_tunnelid = i;
4872 return i;
4873 }
4874 }
4875 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4876 return 0;
4877 }
4878
4879 //
4880 // We're becoming the master. Do any required setup..
4881 //
4882 // This is principally telling all the plugins that we're
4883 // now a master, and telling them about all the sessions
4884 // that are active too..
4885 //
4886 void become_master(void)
4887 {
4888 int s, i;
4889 static struct event_data d[RADIUS_FDS];
4890 struct epoll_event e;
4891
4892 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4893
4894 // running a bunch of iptables commands is slow and can cause
4895 // the master to drop tunnels on takeover--kludge around the
4896 // problem by forking for the moment (note: race)
4897 if (!fork_and_close())
4898 {
4899 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4900 {
4901 if (!session[s].opened) // Not an in-use session.
4902 continue;
4903
4904 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4905 }
4906 exit(0);
4907 }
4908
4909 // add radius fds
4910 e.events = EPOLLIN;
4911 for (i = 0; i < RADIUS_FDS; i++)
4912 {
4913 d[i].type = FD_TYPE_RADIUS;
4914 d[i].index = i;
4915 e.data.ptr = &d[i];
4916
4917 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
4918 }
4919 }
4920
4921 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4922 {
4923 int s, i;
4924 int count = 0;
4925 int buckets[64];
4926
4927 if (CLI_HELP_REQUESTED)
4928 return CLI_HELP_NO_ARGS;
4929
4930 time(&time_now);
4931 for (i = 0; i < 64;++i) buckets[i] = 0;
4932
4933 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4934 {
4935 int idle;
4936 if (!session[s].opened)
4937 continue;
4938
4939 idle = time_now - session[s].last_packet;
4940 idle /= 5 ; // In multiples of 5 seconds.
4941 if (idle < 0)
4942 idle = 0;
4943 if (idle > 63)
4944 idle = 63;
4945
4946 ++count;
4947 ++buckets[idle];
4948 }
4949
4950 for (i = 0; i < 63; ++i)
4951 {
4952 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4953 }
4954 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4955 cli_print(cli, "%d total sessions open.", count);
4956 return CLI_OK;
4957 }
4958
4959 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4960 {
4961 int s, i;
4962 int count = 0;
4963 int buckets[64];
4964
4965 if (CLI_HELP_REQUESTED)
4966 return CLI_HELP_NO_ARGS;
4967
4968 time(&time_now);
4969 for (i = 0; i < 64;++i) buckets[i] = 0;
4970
4971 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4972 {
4973 int open = 0, d;
4974 if (!session[s].opened)
4975 continue;
4976
4977 d = time_now - session[s].opened;
4978 if (d < 0)
4979 d = 0;
4980 while (d > 1 && open < 32)
4981 {
4982 ++open;
4983 d >>= 1; // half.
4984 }
4985 ++count;
4986 ++buckets[open];
4987 }
4988
4989 s = 1;
4990 for (i = 0; i < 30; ++i)
4991 {
4992 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4993 s <<= 1;
4994 }
4995 cli_print(cli, "%d total sessions open.", count);
4996 return CLI_OK;
4997 }
4998
4999 /* Unhide an avp.
5000 *
5001 * This unencodes the AVP using the L2TP secret and the previously
5002 * stored random vector. It overwrites the hidden data with the
5003 * unhidden AVP subformat.
5004 */
5005 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5006 {
5007 MD5_CTX ctx;
5008 uint8_t digest[16];
5009 uint8_t *last;
5010 size_t d = 0;
5011
5012 // Compute initial pad
5013 MD5Init(&ctx);
5014 MD5Update(&ctx, (uint8_t) (type >> 8) & 0xff, 1);
5015 MD5Update(&ctx, (uint8_t) type & 0xff, 1);
5016 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5017 MD5Update(&ctx, vector, vec_len);
5018 MD5Final(digest, &ctx);
5019
5020 // pointer to last decoded 16 octets
5021 last = value;
5022
5023 while (len > 0)
5024 {
5025 // calculate a new pad based on the last decoded block
5026 if (d >= sizeof(digest))
5027 {
5028 MD5Init(&ctx);
5029 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5030 MD5Update(&ctx, last, sizeof(digest));
5031 MD5Final(digest, &ctx);
5032
5033 d = 0;
5034 last = value;
5035 }
5036
5037 *value++ ^= digest[d++];
5038 len--;
5039 }
5040 }
5041
5042 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5043 {
5044 switch (p->op)
5045 {
5046 case FILTER_PORT_OP_EQ: return port == p->port;
5047 case FILTER_PORT_OP_NEQ: return port != p->port;
5048 case FILTER_PORT_OP_GT: return port > p->port;
5049 case FILTER_PORT_OP_LT: return port < p->port;
5050 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5051 }
5052
5053 return 0;
5054 }
5055
5056 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5057 {
5058 switch (op)
5059 {
5060 case FILTER_FLAG_OP_ANY:
5061 return (flags & sflags) || (~flags & cflags);
5062
5063 case FILTER_FLAG_OP_ALL:
5064 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5065
5066 case FILTER_FLAG_OP_EST:
5067 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5068 }
5069
5070 return 0;
5071 }
5072
5073 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5074 {
5075 uint16_t frag_offset;
5076 uint8_t proto;
5077 in_addr_t src_ip;
5078 in_addr_t dst_ip;
5079 uint16_t src_port = 0;
5080 uint16_t dst_port = 0;
5081 uint8_t flags = 0;
5082 ip_filter_rulet *rule;
5083
5084 if (len < 20) // up to end of destination address
5085 return 0;
5086
5087 if ((*buf >> 4) != 4) // IPv4
5088 return 0;
5089
5090 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5091 proto = buf[9];
5092 src_ip = *(in_addr_t *) (buf + 12);
5093 dst_ip = *(in_addr_t *) (buf + 16);
5094
5095 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5096 {
5097 int l = (buf[0] & 0xf) * 4; // length of IP header
5098 if (len < l + 4) // ports
5099 return 0;
5100
5101 src_port = ntohs(*(uint16_t *) (buf + l));
5102 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5103 if (proto == IPPROTO_TCP)
5104 {
5105 if (len < l + 14) // flags
5106 return 0;
5107
5108 flags = buf[l + 13] & 0x3f;
5109 }
5110 }
5111
5112 for (rule = ip_filters[filter].rules; rule->action; rule++)
5113 {
5114 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5115 continue;
5116
5117 if (rule->src_wild != INADDR_BROADCAST &&
5118 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5119 continue;
5120
5121 if (rule->dst_wild != INADDR_BROADCAST &&
5122 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5123 continue;
5124
5125 if (frag_offset)
5126 {
5127 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5128 continue;
5129 }
5130 else
5131 {
5132 if (rule->frag)
5133 continue;
5134
5135 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5136 {
5137 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5138 continue;
5139
5140 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5141 continue;
5142
5143 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5144 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5145 continue;
5146 }
5147 }
5148
5149 // matched
5150 rule->counter++;
5151 return rule->action == FILTER_ACTION_PERMIT;
5152 }
5153
5154 // default deny
5155 return 0;
5156 }