7ce6e6b1c3875b2bdc85dca43dbac87c100866dc
[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 1.111 2005/06/14 04:47:24 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int 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)
330 close(rand_fd);
331
332 rand_fd = -1;
333
334 if (source)
335 {
336 // register changes
337 snprintf(path, sizeof(path), "%s", source);
338
339 if (*path == '/')
340 {
341 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
342 if (rand_fd < 0)
343 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
344 path, strerror(errno));
345 }
346 }
347 }
348
349 // fill buffer with random data
350 void random_data(uint8_t *buf, int len)
351 {
352 int n = 0;
353
354 CSTAT(random_data);
355 if (rand_fd >= 0)
356 {
357 n = read(rand_fd, buf, len);
358 if (n >= len) return;
359 if (n < 0)
360 {
361 if (errno != EAGAIN)
362 {
363 LOG(0, 0, 0, "Error reading from random source: %s\n",
364 strerror(errno));
365
366 // fall back to rand()
367 initrandom(NULL);
368 }
369
370 n = 0;
371 }
372 }
373
374 // append missing data
375 while (n < len)
376 // not using the low order bits from the prng stream
377 buf[n++] = (rand() >> 4) & 0xff;
378 }
379
380 // Add a route
381 //
382 // This adds it to the routing table, advertises it
383 // via BGP if enabled, and stuffs it into the
384 // 'sessionbyip' cache.
385 //
386 // 'ip' and 'mask' must be in _host_ order.
387 //
388 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
389 {
390 struct rtentry r;
391 int i;
392
393 if (!mask) mask = 0xffffffff;
394
395 ip &= mask; // Force the ip to be the first one in the route.
396
397 memset(&r, 0, sizeof(r));
398 r.rt_dev = config->tundevice;
399 r.rt_dst.sa_family = AF_INET;
400 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
401 r.rt_gateway.sa_family = AF_INET;
402 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
403 r.rt_genmask.sa_family = AF_INET;
404 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
405 r.rt_flags = (RTF_UP | RTF_STATIC);
406 if (gw)
407 r.rt_flags |= RTF_GATEWAY;
408 else if (mask == 0xffffffff)
409 r.rt_flags |= RTF_HOST;
410
411 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
412 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
413 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
414
415 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
416 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
417
418 #ifdef BGP
419 if (add)
420 bgp_add_route(htonl(ip), htonl(mask));
421 else
422 bgp_del_route(htonl(ip), htonl(mask));
423 #endif /* BGP */
424
425 // Add/Remove the IPs to the 'sessionbyip' cache.
426 // Note that we add the zero address in the case of
427 // a network route. Roll on CIDR.
428
429 // Note that 's == 0' implies this is the address pool.
430 // We still cache it here, because it will pre-fill
431 // the malloc'ed tree.
432
433 if (s)
434 {
435 if (!add) // Are we deleting a route?
436 s = 0; // Caching the session as '0' is the same as uncaching.
437
438 for (i = ip; (i&mask) == (ip&mask) ; ++i)
439 cache_ipmap(i, s);
440 }
441 }
442
443 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
444 {
445 struct in6_rtmsg rt;
446 char ipv6addr[INET6_ADDRSTRLEN];
447
448 if (ifr6fd < 0)
449 {
450 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
451 return;
452 }
453
454 memset(&rt, 0, sizeof(rt));
455
456 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
457 rt.rtmsg_dst_len = prefixlen;
458 rt.rtmsg_metric = 1;
459 rt.rtmsg_flags = RTF_UP;
460 rt.rtmsg_ifindex = tunidx;
461
462 LOG(1, 0, 0, "Route %s %s/%d\n",
463 add ? "add" : "del",
464 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
465 prefixlen);
466
467 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
468 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
469 strerror(errno));
470
471 // FIXME: need to add BGP routing (RFC2858)
472
473 if (s)
474 {
475 if (!add) // Are we deleting a route?
476 s = 0; // Caching the session as '0' is the same as uncaching.
477
478 cache_ipv6map(ip, prefixlen, s);
479 }
480
481 return;
482 }
483
484 // defined in linux/ipv6.h, but tricky to include from user-space
485 // TODO: move routing to use netlink rather than ioctl
486 struct in6_ifreq {
487 struct in6_addr ifr6_addr;
488 __u32 ifr6_prefixlen;
489 unsigned int ifr6_ifindex;
490 };
491
492 //
493 // Set up TUN interface
494 static void inittun(void)
495 {
496 struct ifreq ifr;
497 struct in6_ifreq ifr6;
498 struct sockaddr_in sin = {0};
499 memset(&ifr, 0, sizeof(ifr));
500 ifr.ifr_flags = IFF_TUN;
501
502 tunfd = open(TUNDEVICE, O_RDWR);
503 if (tunfd < 0)
504 { // fatal
505 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
506 exit(1);
507 }
508 {
509 int flags = fcntl(tunfd, F_GETFL, 0);
510 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
511 }
512 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
513 {
514 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
515 exit(1);
516 }
517 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
518 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
519 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
520
521 sin.sin_family = AF_INET;
522 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
523 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
524
525 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
526 {
527 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
528 exit(1);
529 }
530 /* Bump up the qlen to deal with bursts from the network */
531 ifr.ifr_qlen = 1000;
532 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
533 {
534 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
535 exit(1);
536 }
537 ifr.ifr_flags = IFF_UP;
538 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
539 {
540 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
541 exit(1);
542 }
543 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
544 {
545 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
546 exit(1);
547 }
548 tunidx = ifr.ifr_ifindex;
549
550 // Only setup IPv6 on the tun device if we have a configured prefix
551 if (config->ipv6_prefix.s6_addr[0] > 0) {
552 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
553
554 // Link local address is FE80::1
555 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
556 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
557 ifr6.ifr6_addr.s6_addr[1] = 0x80;
558 ifr6.ifr6_addr.s6_addr[15] = 1;
559 ifr6.ifr6_prefixlen = 64;
560 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
561 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
562 {
563 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
564 " %s\n", strerror(errno));
565 }
566
567 // Global address is prefix::1
568 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
569 ifr6.ifr6_addr = config->ipv6_prefix;
570 ifr6.ifr6_addr.s6_addr[15] = 1;
571 ifr6.ifr6_prefixlen = 64;
572 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
573 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
574 {
575 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
576 strerror(errno));
577 }
578 }
579 }
580
581 // set up UDP port
582 static void initudp(void)
583 {
584 int on = 1;
585 struct sockaddr_in addr;
586
587 // Tunnel
588 memset(&addr, 0, sizeof(addr));
589 addr.sin_family = AF_INET;
590 addr.sin_port = htons(L2TPPORT);
591 addr.sin_addr.s_addr = config->bind_address;
592 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
593 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
594 {
595 int flags = fcntl(udpfd, F_GETFL, 0);
596 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
597 }
598 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
599 {
600 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
601 exit(1);
602 }
603 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
604
605 // Control
606 memset(&addr, 0, sizeof(addr));
607 addr.sin_family = AF_INET;
608 addr.sin_port = htons(NSCTL_PORT);
609 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
610 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
611 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
612 {
613 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
614 exit(1);
615 }
616 }
617
618 //
619 // Find session by IP, < 1 for not found
620 //
621 // Confusingly enough, this 'ip' must be
622 // in _network_ order. This being the common
623 // case when looking it up from IP packet headers.
624 //
625 // We actually use this cache for two things.
626 // #1. For used IP addresses, this maps to the
627 // session ID that it's used by.
628 // #2. For un-used IP addresses, this maps to the
629 // index into the pool table that contains that
630 // IP address.
631 //
632
633 static int lookup_ipmap(in_addr_t ip)
634 {
635 uint8_t *a = (uint8_t *) &ip;
636 uint8_t **d = (uint8_t **) ip_hash;
637
638 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
639 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
640 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
641
642 return (int) (intptr_t) d[(size_t) *a];
643 }
644
645 static int lookup_ipv6map(struct in6_addr ip)
646 {
647 struct ipv6radix *curnode;
648 int i;
649 int s;
650 char ipv6addr[INET6_ADDRSTRLEN];
651
652 curnode = &ipv6_hash[ip.s6_addr[0]];
653 i = 1;
654 s = curnode->sess;
655
656 while (s == 0 && i < 15 && curnode->branch != NULL)
657 {
658 curnode = &curnode->branch[ip.s6_addr[i]];
659 s = curnode->sess;
660 i++;
661 }
662
663 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
664 inet_ntop(AF_INET6, &ip, ipv6addr,
665 INET6_ADDRSTRLEN),
666 s);
667
668 return s;
669 }
670
671 sessionidt sessionbyip(in_addr_t ip)
672 {
673 int s = lookup_ipmap(ip);
674 CSTAT(sessionbyip);
675
676 if (s > 0 && s < MAXSESSION && session[s].opened)
677 return (sessionidt) s;
678
679 return 0;
680 }
681
682 sessionidt sessionbyipv6(struct in6_addr ip)
683 {
684 int s;
685 CSTAT(sessionbyipv6);
686
687 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
688 (ip.s6_addr[0] == 0xFE && ip.s6_addr[1] == 0x80 &&
689 (ip.s6_addr16[1] == ip.s6_addr16[2] == ip.s6_addr16[3] == 0))) {
690 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
691 } else {
692 s = lookup_ipv6map(ip);
693 }
694
695 if (s > 0 && s < MAXSESSION && session[s].opened)
696 return s;
697
698 return 0;
699 }
700
701 //
702 // Take an IP address in HOST byte order and
703 // add it to the sessionid by IP cache.
704 //
705 // (It's actually cached in network order)
706 //
707 static void cache_ipmap(in_addr_t ip, int s)
708 {
709 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
710 uint8_t *a = (uint8_t *) &nip;
711 uint8_t **d = (uint8_t **) ip_hash;
712 int i;
713
714 for (i = 0; i < 3; i++)
715 {
716 if (!d[(size_t) a[i]])
717 {
718 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
719 return;
720 }
721
722 d = (uint8_t **) d[(size_t) a[i]];
723 }
724
725 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
726
727 if (s > 0)
728 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
729
730 else if (s == 0)
731 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
732 // else a map to an ip pool index.
733 }
734
735 static void uncache_ipmap(in_addr_t ip)
736 {
737 cache_ipmap(ip, 0); // Assign it to the NULL session.
738 }
739
740 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
741 {
742 int i;
743 int bytes;
744 struct ipv6radix *curnode;
745 char ipv6addr[INET6_ADDRSTRLEN];
746
747 curnode = &ipv6_hash[ip.s6_addr[0]];
748
749 bytes = prefixlen >> 3;
750 i = 1;
751 while (i < bytes) {
752 if (curnode->branch == NULL)
753 {
754 if (!(curnode->branch = calloc(256,
755 sizeof (struct ipv6radix))))
756 return;
757 }
758 curnode = &curnode->branch[ip.s6_addr[i]];
759 i++;
760 }
761
762 curnode->sess = s;
763
764 if (s > 0)
765 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
766 inet_ntop(AF_INET6, &ip, ipv6addr,
767 INET6_ADDRSTRLEN),
768 prefixlen);
769 else if (s == 0)
770 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
771 inet_ntop(AF_INET6, &ip, ipv6addr,
772 INET6_ADDRSTRLEN),
773 prefixlen);
774 }
775
776 //
777 // CLI list to dump current ipcache.
778 //
779 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
780 {
781 char **d = (char **) ip_hash, **e, **f, **g;
782 int i, j, k, l;
783 int count = 0;
784
785 if (CLI_HELP_REQUESTED)
786 return CLI_HELP_NO_ARGS;
787
788 cli_print(cli, "%7s %s", "Sess#", "IP Address");
789
790 for (i = 0; i < 256; ++i)
791 {
792 if (!d[i])
793 continue;
794 e = (char **) d[i];
795 for (j = 0; j < 256; ++j)
796 {
797 if (!e[j])
798 continue;
799 f = (char **) e[j];
800 for (k = 0; k < 256; ++k)
801 {
802 if (!f[k])
803 continue;
804 g = (char **)f[k];
805 for (l = 0; l < 256; ++l)
806 {
807 if (!g[l])
808 continue;
809 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
810 ++count;
811 }
812 }
813 }
814 }
815 cli_print(cli, "%d entries in cache", count);
816 return CLI_OK;
817 }
818
819
820 // Find session by username, 0 for not found
821 // walled garden users aren't authenticated, so the username is
822 // reasonably useless. Ignore them to avoid incorrect actions
823 //
824 // This is VERY inefficent. Don't call it often. :)
825 //
826 sessionidt sessionbyuser(char *username)
827 {
828 int s;
829 CSTAT(sessionbyuser);
830
831 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
832 {
833 if (!session[s].opened)
834 continue;
835
836 if (session[s].walled_garden)
837 continue; // Skip walled garden users.
838
839 if (!strncmp(session[s].user, username, 128))
840 return s;
841
842 }
843 return 0; // Not found.
844 }
845
846 void send_garp(in_addr_t ip)
847 {
848 int s;
849 struct ifreq ifr;
850 uint8_t mac[6];
851
852 s = socket(PF_INET, SOCK_DGRAM, 0);
853 if (s < 0)
854 {
855 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
856 return;
857 }
858 memset(&ifr, 0, sizeof(ifr));
859 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
860 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
861 {
862 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
863 close(s);
864 return;
865 }
866 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
867 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
868 {
869 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
870 close(s);
871 return;
872 }
873 close(s);
874 sendarp(ifr.ifr_ifindex, mac, ip);
875 }
876
877 static sessiont *sessiontbysessionidt(sessionidt s)
878 {
879 if (!s || s >= MAXSESSION) return NULL;
880 return &session[s];
881 }
882
883 static sessionidt sessionidtbysessiont(sessiont *s)
884 {
885 sessionidt val = s-session;
886 if (s < session || val >= MAXSESSION) return 0;
887 return val;
888 }
889
890 // actually send a control message for a specific tunnel
891 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
892 {
893 struct sockaddr_in addr;
894
895 CSTAT(tunnelsend);
896
897 if (!t)
898 {
899 static int backtrace_count = 0;
900 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
901 STAT(tunnel_tx_errors);
902 log_backtrace(backtrace_count, 5)
903 return;
904 }
905
906 if (!tunnel[t].ip)
907 {
908 static int backtrace_count = 0;
909 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
910 log_backtrace(backtrace_count, 5)
911 STAT(tunnel_tx_errors);
912 return;
913 }
914
915 memset(&addr, 0, sizeof(addr));
916 addr.sin_family = AF_INET;
917 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
918 addr.sin_port = htons(tunnel[t].port);
919
920 // sequence expected, if sequence in message
921 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
922
923 // If this is a control message, deal with retries
924 if (*buf & 0x80)
925 {
926 tunnel[t].last = time_now; // control message sent
927 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
928 if (tunnel[t].try > 1)
929 {
930 STAT(tunnel_retries);
931 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
932 }
933 }
934
935 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
936 {
937 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
938 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
939 STAT(tunnel_tx_errors);
940 return;
941 }
942
943 LOG_HEX(5, "Send Tunnel Data", buf, l);
944 STAT(tunnel_tx_packets);
945 INC_STAT(tunnel_tx_bytes, l);
946 }
947
948 //
949 // Tiny helper function to write data to
950 // the 'tun' device.
951 //
952 int tun_write(uint8_t * data, int size)
953 {
954 return write(tunfd, data, size);
955 }
956
957 // process outgoing (to tunnel) IP
958 //
959 static void processipout(uint8_t * buf, int len)
960 {
961 sessionidt s;
962 sessiont *sp;
963 tunnelidt t;
964 in_addr_t ip;
965
966 char *data = buf; // Keep a copy of the originals.
967 int size = len;
968
969 uint8_t b[MAXETHER + 20];
970
971 CSTAT(processipout);
972
973 if (len < MIN_IP_SIZE)
974 {
975 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
976 STAT(tun_rx_errors);
977 return;
978 }
979 if (len >= MAXETHER)
980 {
981 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
982 STAT(tun_rx_errors);
983 return;
984 }
985
986 // Skip the tun header
987 buf += 4;
988 len -= 4;
989
990 // Got an IP header now
991 if (*(uint8_t *)(buf) >> 4 != 4)
992 {
993 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
994 return;
995 }
996
997 ip = *(uint32_t *)(buf + 16);
998 if (!(s = sessionbyip(ip)))
999 {
1000 // Is this a packet for a session that doesn't exist?
1001 static int rate = 0; // Number of ICMP packets we've sent this second.
1002 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1003
1004 if (last != time_now)
1005 {
1006 last = time_now;
1007 rate = 0;
1008 }
1009
1010 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1011 {
1012 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1013 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1014 config->bind_address ? config->bind_address : my_address, buf, len);
1015 }
1016 return;
1017 }
1018 t = session[s].tunnel;
1019 sp = &session[s];
1020
1021 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1022 if (config->max_packets > 0)
1023 {
1024 if (sess_local[s].last_packet_out == TIME)
1025 {
1026 int max = config->max_packets;
1027
1028 // All packets for throttled sessions are handled by the
1029 // master, so further limit by using the throttle rate.
1030 // A bit of a kludge, since throttle rate is in kbps,
1031 // but should still be generous given our average DSL
1032 // packet size is 200 bytes: a limit of 28kbps equates
1033 // to around 180 packets per second.
1034 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1035 max = sp->throttle_out;
1036
1037 if (++sess_local[s].packets_out > max)
1038 {
1039 sess_local[s].packets_dropped++;
1040 return;
1041 }
1042 }
1043 else
1044 {
1045 if (sess_local[s].packets_dropped)
1046 {
1047 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1048 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1049 sess_local[s].packets_dropped, sess_local[s].packets_out,
1050 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1051 sp->user);
1052 }
1053
1054 sess_local[s].last_packet_out = TIME;
1055 sess_local[s].packets_out = 1;
1056 sess_local[s].packets_dropped = 0;
1057 }
1058 }
1059
1060 // run access-list if any
1061 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1062 return;
1063
1064 if (sp->tbf_out)
1065 {
1066 // Are we throttling this session?
1067 if (config->cluster_iam_master)
1068 tbf_queue_packet(sp->tbf_out, data, size);
1069 else
1070 master_throttle_packet(sp->tbf_out, data, size);
1071 return;
1072 }
1073 else if (sp->walled_garden && !config->cluster_iam_master)
1074 {
1075 // We are walled-gardening this
1076 master_garden_packet(s, data, size);
1077 return;
1078 }
1079
1080 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1081
1082 // Add on L2TP header
1083 {
1084 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1085 if (!p) return;
1086 tunnelsend(b, len + (p-b), t); // send it...
1087 }
1088
1089 // Snooping this session, send it to intercept box
1090 if (sp->snoop_ip && sp->snoop_port)
1091 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1092
1093 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1094 sp->cout_delta += len;
1095 sp->pout++;
1096 udp_tx += len;
1097
1098 sess_local[s].cout += len; // To send to master..
1099 sess_local[s].pout++;
1100 }
1101
1102 // process outgoing (to tunnel) IPv6
1103 //
1104 static void processipv6out(uint8_t * buf, int len)
1105 {
1106 sessionidt s;
1107 sessiont *sp;
1108 tunnelidt t;
1109 in_addr_t ip;
1110 struct in6_addr ip6;
1111
1112 char *data = buf; // Keep a copy of the originals.
1113 int size = len;
1114
1115 uint8_t b[MAXETHER + 20];
1116
1117 CSTAT(processipv6out);
1118
1119 if (len < MIN_IP_SIZE)
1120 {
1121 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1122 STAT(tunnel_tx_errors);
1123 return;
1124 }
1125 if (len >= MAXETHER)
1126 {
1127 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1128 STAT(tunnel_tx_errors);
1129 return;
1130 }
1131
1132 // Skip the tun header
1133 buf += 4;
1134 len -= 4;
1135
1136 // Got an IP header now
1137 if (*(uint8_t *)(buf) >> 4 != 6)
1138 {
1139 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1140 return;
1141 }
1142
1143 ip6 = *(struct in6_addr *)(buf+24);
1144 s = sessionbyipv6(ip6);
1145
1146 if (s == 0)
1147 {
1148 ip = *(uint32_t *)(buf + 32);
1149 s = sessionbyip(ip);
1150 }
1151
1152 if (s == 0)
1153 {
1154 // Is this a packet for a session that doesn't exist?
1155 static int rate = 0; // Number of ICMP packets we've sent this second.
1156 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1157
1158 if (last != time_now)
1159 {
1160 last = time_now;
1161 rate = 0;
1162 }
1163
1164 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1165 {
1166 // FIXME: Should send icmp6 host unreachable
1167 }
1168 return;
1169 }
1170 t = session[s].tunnel;
1171 sp = &session[s];
1172
1173 // FIXME: add DoS prevention/filters?
1174
1175 if (sp->tbf_out)
1176 {
1177 // Are we throttling this session?
1178 if (config->cluster_iam_master)
1179 tbf_queue_packet(sp->tbf_out, data, size);
1180 else
1181 master_throttle_packet(sp->tbf_out, data, size);
1182 return;
1183 }
1184 else if (sp->walled_garden && !config->cluster_iam_master)
1185 {
1186 // We are walled-gardening this
1187 master_garden_packet(s, data, size);
1188 return;
1189 }
1190
1191 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1192
1193 // Add on L2TP header
1194 {
1195 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIPV6);
1196 if (!p) return;
1197 tunnelsend(b, len + (p-b), t); // send it...
1198 }
1199
1200 // Snooping this session, send it to intercept box
1201 if (sp->snoop_ip && sp->snoop_port)
1202 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1203
1204 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1205 sp->cout_delta += len;
1206 sp->pout++;
1207 udp_tx += len;
1208
1209 sess_local[s].cout += len; // To send to master..
1210 sess_local[s].pout++;
1211 }
1212
1213 //
1214 // Helper routine for the TBF filters.
1215 // Used to send queued data in to the user!
1216 //
1217 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1218 {
1219 sessiont *sp;
1220 tunnelidt t;
1221 in_addr_t ip;
1222
1223 uint8_t b[MAXETHER + 20];
1224
1225 if (len < 0 || len > MAXETHER)
1226 {
1227 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1228 return;
1229 }
1230
1231 // Skip the tun header
1232 buf += 4;
1233 len -= 4;
1234
1235 ip = *(in_addr_t *)(buf + 16);
1236
1237 if (!session[s].ip)
1238 return;
1239
1240 t = session[s].tunnel;
1241 sp = &session[s];
1242
1243 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1244
1245 // Add on L2TP header
1246 {
1247 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1248 if (!p) return;
1249 tunnelsend(b, len + (p-b), t); // send it...
1250 }
1251
1252 // Snooping this session.
1253 if (sp->snoop_ip && sp->snoop_port)
1254 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1255
1256 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1257 sp->cout_delta += len;
1258 sp->pout++;
1259 udp_tx += len;
1260
1261 sess_local[s].cout += len; // To send to master..
1262 sess_local[s].pout++;
1263 }
1264
1265 // add an AVP (16 bit)
1266 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1267 {
1268 uint16_t l = (m ? 0x8008 : 0x0008);
1269 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1270 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1271 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1272 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1273 c->length += 8;
1274 }
1275
1276 // add an AVP (32 bit)
1277 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1278 {
1279 uint16_t l = (m ? 0x800A : 0x000A);
1280 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1281 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1282 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1283 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1284 c->length += 10;
1285 }
1286
1287 // add an AVP (string)
1288 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1289 {
1290 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1291 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1292 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1293 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1294 memcpy(c->buf + c->length + 6, val, strlen(val));
1295 c->length += 6 + strlen(val);
1296 }
1297
1298 // add a binary AVP
1299 static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
1300 {
1301 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1302 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1303 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1304 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1305 memcpy(c->buf + c->length + 6, val, len);
1306 c->length += 6 + len;
1307 }
1308
1309 // new control connection
1310 static controlt *controlnew(uint16_t mtype)
1311 {
1312 controlt *c;
1313 if (!controlfree)
1314 c = malloc(sizeof(controlt));
1315 else
1316 {
1317 c = controlfree;
1318 controlfree = c->next;
1319 }
1320 assert(c);
1321 c->next = 0;
1322 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1323 c->length = 12;
1324 control16(c, 0, mtype, 1);
1325 return c;
1326 }
1327
1328 // send zero block if nothing is waiting
1329 // (ZLB send).
1330 static void controlnull(tunnelidt t)
1331 {
1332 uint8_t buf[12];
1333 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1334 return;
1335
1336 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1337 *(uint16_t *) (buf + 2) = htons(12); // length
1338 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1339 *(uint16_t *) (buf + 6) = htons(0); // session
1340 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1341 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1342 tunnelsend(buf, 12, t);
1343 }
1344
1345 // add a control message to a tunnel, and send if within window
1346 static void controladd(controlt * c, tunnelidt t, sessionidt far)
1347 {
1348 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1349 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1350 *(uint16_t *) (c->buf + 6) = htons(far); // session
1351 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1352 tunnel[t].ns++; // advance sequence
1353 // link in message in to queue
1354 if (tunnel[t].controlc)
1355 tunnel[t].controle->next = c;
1356 else
1357 tunnel[t].controls = c;
1358
1359 tunnel[t].controle = c;
1360 tunnel[t].controlc++;
1361
1362 // send now if space in window
1363 if (tunnel[t].controlc <= tunnel[t].window)
1364 {
1365 tunnel[t].try = 0; // first send
1366 tunnelsend(c->buf, c->length, t);
1367 }
1368 }
1369
1370 //
1371 // Throttle or Unthrottle a session
1372 //
1373 // Throttle the data from/to through a session to no more than
1374 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1375 // user).
1376 //
1377 // If either value is -1, the current value is retained for that
1378 // direction.
1379 //
1380 void throttle_session(sessionidt s, int rate_in, int rate_out)
1381 {
1382 if (!session[s].opened)
1383 return; // No-one home.
1384
1385 if (!*session[s].user)
1386 return; // User not logged in
1387
1388 if (rate_in >= 0)
1389 {
1390 int bytes = rate_in * 1024 / 8; // kbits to bytes
1391 if (session[s].tbf_in)
1392 free_tbf(session[s].tbf_in);
1393
1394 if (rate_in > 0)
1395 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1396 else
1397 session[s].tbf_in = 0;
1398
1399 session[s].throttle_in = rate_in;
1400 }
1401
1402 if (rate_out >= 0)
1403 {
1404 int bytes = rate_out * 1024 / 8;
1405 if (session[s].tbf_out)
1406 free_tbf(session[s].tbf_out);
1407
1408 if (rate_out > 0)
1409 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1410 else
1411 session[s].tbf_out = 0;
1412
1413 session[s].throttle_out = rate_out;
1414 }
1415 }
1416
1417 // add/remove filters from session (-1 = no change)
1418 static void filter_session(sessionidt s, int filter_in, int filter_out)
1419 {
1420 if (!session[s].opened)
1421 return; // No-one home.
1422
1423 if (!*session[s].user)
1424 return; // User not logged in
1425
1426 // paranoia
1427 if (filter_in > MAXFILTER) filter_in = -1;
1428 if (filter_out > MAXFILTER) filter_out = -1;
1429 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1430 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1431
1432 if (filter_in >= 0)
1433 {
1434 if (session[s].filter_in)
1435 ip_filters[session[s].filter_in - 1].used--;
1436
1437 if (filter_in > 0)
1438 ip_filters[filter_in - 1].used++;
1439
1440 session[s].filter_in = filter_in;
1441 }
1442
1443 if (filter_out >= 0)
1444 {
1445 if (session[s].filter_out)
1446 ip_filters[session[s].filter_out - 1].used--;
1447
1448 if (filter_out > 0)
1449 ip_filters[filter_out - 1].used++;
1450
1451 session[s].filter_out = filter_out;
1452 }
1453 }
1454
1455 // start tidy shutdown of session
1456 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1457 {
1458 int walled_garden = session[s].walled_garden;
1459
1460
1461 CSTAT(sessionshutdown);
1462
1463 if (!session[s].opened)
1464 {
1465 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1466 return; // not a live session
1467 }
1468
1469 if (!session[s].die)
1470 {
1471 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1472 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1473 run_plugins(PLUGIN_KILL_SESSION, &data);
1474 }
1475
1476 if (session[s].ip && !walled_garden && !session[s].die)
1477 {
1478 // RADIUS Stop message
1479 uint16_t r = sess_local[s].radius;
1480 if (!r)
1481 r = radiusnew(s);
1482
1483 if (r)
1484 {
1485 // stop, if not already trying
1486 if (radius[r].state != RADIUSSTOP)
1487 radiussend(r, RADIUSSTOP);
1488 }
1489 else
1490 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1491
1492 // Save counters to dump to accounting file
1493 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1494 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1495 }
1496
1497 if (session[s].ip)
1498 { // IP allocated, clear and unroute
1499 int r;
1500 int routed = 0;
1501 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1502 {
1503 if ((session[s].ip & session[s].route[r].mask) ==
1504 (session[s].route[r].ip & session[s].route[r].mask))
1505 routed++;
1506
1507 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1508 session[s].route[r].ip = 0;
1509 }
1510
1511 if (session[s].ip_pool_index == -1) // static ip
1512 {
1513 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1514 session[s].ip = 0;
1515 }
1516 else
1517 free_ip_address(s);
1518
1519 // unroute IPv6, if setup
1520 if (session[s].flags & SF_IPV6_ROUTED)
1521 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1522 }
1523
1524 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1525 throttle_session(s, 0, 0);
1526
1527 if (result)
1528 { // Send CDN
1529 controlt *c = controlnew(14); // sending CDN
1530 if (error)
1531 {
1532 char buf[4];
1533 *(uint16_t *) buf = htons(result);
1534 *(uint16_t *) (buf+2) = htons(error);
1535 controlb(c, 1, buf, 4, 1);
1536 }
1537 else
1538 control16(c, 1, result, 1);
1539
1540 control16(c, 14, s, 1); // assigned session (our end)
1541 controladd(c, session[s].tunnel, session[s].far); // send the message
1542 }
1543
1544 if (!session[s].die)
1545 session[s].die = TIME + 150; // Clean up in 15 seconds
1546
1547 // update filter refcounts
1548 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1549 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1550
1551 cluster_send_session(s);
1552 }
1553
1554 void sendipcp(tunnelidt t, sessionidt s)
1555 {
1556 uint8_t buf[MAXCONTROL];
1557 uint16_t r = sess_local[s].radius;
1558 uint8_t *q;
1559
1560 CSTAT(sendipcp);
1561
1562 if (!r)
1563 r = radiusnew(s);
1564
1565 if (!r)
1566 {
1567 sessionshutdown(s, "No free RADIUS sessions for IPCP", 3, 0);
1568 return;
1569 }
1570
1571 if (radius[r].state != RADIUSIPCP)
1572 {
1573 radius[r].state = RADIUSIPCP;
1574 radius[r].try = 0;
1575 }
1576
1577 radius[r].retry = backoff(radius[r].try++);
1578 if (radius[r].try > 10)
1579 {
1580 radiusclear(r, s); // Clear radius session.
1581 sessionshutdown(s, "No reply to IPCP.", 3, 0);
1582 return;
1583 }
1584
1585 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1586 if (!q) return;
1587
1588 *q = ConfigReq;
1589 q[1] = r >> RADIUS_SHIFT; // ID, dont care, we only send one type of request
1590 *(uint16_t *) (q + 2) = htons(10);
1591 q[4] = 3;
1592 q[5] = 6;
1593 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1594 config->bind_address ? config->bind_address :
1595 my_address; // send my IP
1596
1597 tunnelsend(buf, 10 + (q - buf), t); // send it
1598 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1599
1600 // If we have an IPv6 prefix length configured, assume we should
1601 // try to negotiate an IPv6 session as well. Unless we've had a
1602 // (N)ACK for IPV6CP.
1603 if (config->ipv6_prefix.s6_addr[0] > 0 &&
1604 !(session[s].flags & SF_IPV6CP_ACKED) &&
1605 !(session[s].flags & SF_IPV6_NACKED))
1606 {
1607 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
1608 if (!q) return;
1609
1610 *q = ConfigReq;
1611 q[1] = r >> RADIUS_SHIFT; // ID, don't care, we
1612 // only send one type
1613 // of request
1614 *(uint16_t *) (q + 2) = htons(14);
1615 q[4] = 1;
1616 q[5] = 10;
1617 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1618 *(uint32_t *) (q + 10) = 0;
1619 q[13] = 1;
1620
1621 tunnelsend(buf, 14 + (q - buf), t); // send it
1622 }
1623 }
1624
1625 static void sessionclear(sessionidt s)
1626 {
1627 memset(&session[s], 0, sizeof(session[s]));
1628 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1629 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1630
1631 session[s].tunnel = T_FREE; // Mark it as free.
1632 session[s].next = sessionfree;
1633 sessionfree = s;
1634 }
1635
1636 // kill a session now
1637 void sessionkill(sessionidt s, char *reason)
1638 {
1639
1640 CSTAT(sessionkill);
1641
1642 if (!session[s].opened) // not alive
1643 return;
1644
1645 if (session[s].next)
1646 {
1647 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1648 return;
1649 }
1650
1651 session[s].die = TIME;
1652 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1653 if (sess_local[s].radius)
1654 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1655
1656 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1657 sessionclear(s);
1658 cluster_send_session(s);
1659 }
1660
1661 static void tunnelclear(tunnelidt t)
1662 {
1663 if (!t) return;
1664 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1665 tunnel[t].state = TUNNELFREE;
1666 }
1667
1668 // kill a tunnel now
1669 static void tunnelkill(tunnelidt t, char *reason)
1670 {
1671 sessionidt s;
1672 controlt *c;
1673
1674 CSTAT(tunnelkill);
1675
1676 tunnel[t].state = TUNNELDIE;
1677
1678 // free control messages
1679 while ((c = tunnel[t].controls))
1680 {
1681 controlt * n = c->next;
1682 tunnel[t].controls = n;
1683 tunnel[t].controlc--;
1684 c->next = controlfree;
1685 controlfree = c;
1686 }
1687 // kill sessions
1688 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1689 if (session[s].tunnel == t)
1690 sessionkill(s, reason);
1691
1692 // free tunnel
1693 tunnelclear(t);
1694 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1695 cli_tunnel_actions[t].action = 0;
1696 cluster_send_tunnel(t);
1697 }
1698
1699 // shut down a tunnel cleanly
1700 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1701 {
1702 sessionidt s;
1703
1704 CSTAT(tunnelshutdown);
1705
1706 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1707 {
1708 // never set up, can immediately kill
1709 tunnelkill(t, reason);
1710 return;
1711 }
1712 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1713
1714 // close session
1715 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1716 if (session[s].tunnel == t)
1717 sessionshutdown(s, reason, 0, 0);
1718
1719 tunnel[t].state = TUNNELDIE;
1720 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1721 cluster_send_tunnel(t);
1722 // TBA - should we wait for sessions to stop?
1723 if (result)
1724 {
1725 controlt *c = controlnew(4); // sending StopCCN
1726 if (error)
1727 {
1728 char buf[64];
1729 int l = 4;
1730 *(uint16_t *) buf = htons(result);
1731 *(uint16_t *) (buf+2) = htons(error);
1732 if (msg)
1733 {
1734 int m = strlen(msg);
1735 if (m + 4 > sizeof(buf))
1736 m = sizeof(buf) - 4;
1737
1738 memcpy(buf+4, msg, m);
1739 l += m;
1740 }
1741
1742 controlb(c, 1, buf, l, 1);
1743 }
1744 else
1745 control16(c, 1, result, 1);
1746
1747 control16(c, 9, t, 1); // assigned tunnel (our end)
1748 controladd(c, t, 0); // send the message
1749 }
1750 }
1751
1752 // read and process packet on tunnel (UDP)
1753 void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
1754 {
1755 char *chapresponse = NULL;
1756 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1757 uint8_t *p = buf + 2;
1758
1759
1760 CSTAT(processudp);
1761
1762 udp_rx += len;
1763 udp_rx_pkt++;
1764 LOG_HEX(5, "UDP Data", buf, len);
1765 STAT(tunnel_rx_packets);
1766 INC_STAT(tunnel_rx_bytes, len);
1767 if (len < 6)
1768 {
1769 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1770 STAT(tunnel_rx_errors);
1771 return;
1772 }
1773 if ((buf[1] & 0x0F) != 2)
1774 {
1775 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1776 STAT(tunnel_rx_errors);
1777 return;
1778 }
1779 if (*buf & 0x40)
1780 { // length
1781 l = ntohs(*(uint16_t *) p);
1782 p += 2;
1783 }
1784 t = ntohs(*(uint16_t *) p);
1785 p += 2;
1786 s = ntohs(*(uint16_t *) p);
1787 p += 2;
1788 if (s >= MAXSESSION)
1789 {
1790 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1791 STAT(tunnel_rx_errors);
1792 return;
1793 }
1794 if (t >= MAXTUNNEL)
1795 {
1796 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1797 STAT(tunnel_rx_errors);
1798 return;
1799 }
1800 if (*buf & 0x08)
1801 { // ns/nr
1802 ns = ntohs(*(uint16_t *) p);
1803 p += 2;
1804 nr = ntohs(*(uint16_t *) p);
1805 p += 2;
1806 }
1807 if (*buf & 0x02)
1808 { // offset
1809 uint16_t o = ntohs(*(uint16_t *) p);
1810 p += o + 2;
1811 }
1812 if ((p - buf) > l)
1813 {
1814 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1815 STAT(tunnel_rx_errors);
1816 return;
1817 }
1818 l -= (p - buf);
1819 if (*buf & 0x80)
1820 { // control
1821 uint16_t message = 0xFFFF; // message type
1822 uint8_t fatal = 0;
1823 uint8_t mandatory = 0;
1824 uint8_t authtype = 0; // proxy auth type
1825 uint16_t asession = 0; // assigned session
1826 uint32_t amagic = 0; // magic number
1827 uint8_t aflags = 0; // flags from last LCF
1828 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1829 char called[MAXTEL] = ""; // called number
1830 char calling[MAXTEL] = ""; // calling number
1831
1832 if (!config->cluster_iam_master)
1833 {
1834 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1835 return;
1836 }
1837
1838 // control messages must have bits 0x80|0x40|0x08
1839 // (type, length and sequence) set, and bits 0x02|0x01
1840 // (offset and priority) clear
1841 if ((*buf & 0xCB) != 0xC8)
1842 {
1843 LOG(1, s, t, "Bad control header %02X\n", *buf);
1844 STAT(tunnel_rx_errors);
1845 return;
1846 }
1847
1848 // check for duplicate tunnel open message
1849 if (!t && ns == 0)
1850 {
1851 int i;
1852
1853 //
1854 // Is this a duplicate of the first packet? (SCCRQ)
1855 //
1856 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1857 {
1858 if (tunnel[i].state != TUNNELOPENING ||
1859 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1860 tunnel[i].port != ntohs(addr->sin_port) )
1861 continue;
1862 t = i;
1863 LOG(3, s, t, "Duplicate SCCRQ?\n");
1864 break;
1865 }
1866 }
1867
1868 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1869 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1870
1871 // if no tunnel specified, assign one
1872 if (!t)
1873 {
1874 if (!(t = new_tunnel()))
1875 {
1876 LOG(1, 0, 0, "No more tunnels\n");
1877 STAT(tunnel_overflow);
1878 return;
1879 }
1880 tunnelclear(t);
1881 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1882 tunnel[t].port = ntohs(addr->sin_port);
1883 tunnel[t].window = 4; // default window
1884 STAT(tunnel_created);
1885 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1886 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1887 }
1888
1889 // If the 'ns' just received is not the 'nr' we're
1890 // expecting, just send an ack and drop it.
1891 //
1892 // if 'ns' is less, then we got a retransmitted packet.
1893 // if 'ns' is greater than missed a packet. Either way
1894 // we should ignore it.
1895 if (ns != tunnel[t].nr)
1896 {
1897 // is this the sequence we were expecting?
1898 STAT(tunnel_rx_errors);
1899 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1900 t, ns, tunnel[t].nr);
1901
1902 if (l) // Is this not a ZLB?
1903 controlnull(t);
1904 return;
1905 }
1906
1907 // This is used to time out old tunnels
1908 tunnel[t].lastrec = time_now;
1909
1910 // check sequence of this message
1911 {
1912 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1913 // some to clear maybe?
1914 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1915 {
1916 controlt *c = tunnel[t].controls;
1917 tunnel[t].controls = c->next;
1918 tunnel[t].controlc--;
1919 c->next = controlfree;
1920 controlfree = c;
1921 skip--;
1922 tunnel[t].try = 0; // we have progress
1923 }
1924
1925 // receiver advance (do here so quoted correctly in any sends below)
1926 if (l) tunnel[t].nr = (ns + 1);
1927 if (skip < 0) skip = 0;
1928 if (skip < tunnel[t].controlc)
1929 {
1930 // some control packets can now be sent that were previous stuck out of window
1931 int tosend = tunnel[t].window - skip;
1932 controlt *c = tunnel[t].controls;
1933 while (c && skip)
1934 {
1935 c = c->next;
1936 skip--;
1937 }
1938 while (c && tosend)
1939 {
1940 tunnel[t].try = 0; // first send
1941 tunnelsend(c->buf, c->length, t);
1942 c = c->next;
1943 tosend--;
1944 }
1945 }
1946 if (!tunnel[t].controlc)
1947 tunnel[t].retry = 0; // caught up
1948 }
1949 if (l)
1950 { // if not a null message
1951 int result = 0;
1952 int error = 0;
1953 char *msg = 0;
1954
1955 // process AVPs
1956 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1957 {
1958 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1959 uint8_t *b = p;
1960 uint8_t flags = *p;
1961 uint16_t mtype;
1962 if (n > l)
1963 {
1964 LOG(1, s, t, "Invalid length in AVP\n");
1965 STAT(tunnel_rx_errors);
1966 return;
1967 }
1968 p += n; // next
1969 l -= n;
1970 if (flags & 0x3C) // reserved bits, should be clear
1971 {
1972 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1973 fatal = flags;
1974 result = 2; // general error
1975 error = 3; // reserved field non-zero
1976 msg = 0;
1977 continue; // next
1978 }
1979 b += 2;
1980 if (*(uint16_t *) (b))
1981 {
1982 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1983 fatal = flags;
1984 result = 2; // general error
1985 error = 6; // generic vendor-specific error
1986 msg = "unsupported vendor-specific";
1987 continue; // next
1988 }
1989 b += 2;
1990 mtype = ntohs(*(uint16_t *) (b));
1991 b += 2;
1992 n -= 6;
1993
1994 if (flags & 0x40)
1995 {
1996 uint16_t orig_len;
1997
1998 // handle hidden AVPs
1999 if (!*config->l2tpsecret)
2000 {
2001 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2002 fatal = flags;
2003 result = 2; // general error
2004 error = 6; // generic vendor-specific error
2005 msg = "secret not specified";
2006 continue;
2007 }
2008 if (!session[s].random_vector_length)
2009 {
2010 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2011 fatal = flags;
2012 result = 2; // general error
2013 error = 6; // generic
2014 msg = "no random vector";
2015 continue;
2016 }
2017 if (n < 8)
2018 {
2019 LOG(2, s, t, "Short hidden AVP.\n");
2020 fatal = flags;
2021 result = 2; // general error
2022 error = 2; // length is wrong
2023 msg = 0;
2024 continue;
2025 }
2026
2027 // Unhide the AVP
2028 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2029
2030 orig_len = ntohs(*(uint16_t *) b);
2031 if (orig_len > n + 2)
2032 {
2033 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2034 orig_len, n);
2035
2036 fatal = flags;
2037 result = 2; // general error
2038 error = 2; // length is wrong
2039 msg = 0;
2040 continue;
2041 }
2042
2043 b += 2;
2044 n = orig_len;
2045 }
2046
2047 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, avp_name(mtype), n,
2048 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2049
2050 switch (mtype)
2051 {
2052 case 0: // message type
2053 message = ntohs(*(uint16_t *) b);
2054 mandatory = flags & 0x80;
2055 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_type(message));
2056 break;
2057 case 1: // result code
2058 {
2059 uint16_t rescode = ntohs(*(uint16_t *) b);
2060 const char* resdesc = "(unknown)";
2061 if (message == 4)
2062 { /* StopCCN */
2063 resdesc = stopccn_result_code(rescode);
2064 }
2065 else if (message == 14)
2066 { /* CDN */
2067 resdesc = cdn_result_code(rescode);
2068 }
2069
2070 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2071 if (n >= 4)
2072 {
2073 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2074 LOG(4, s, t, " Error Code %d: %s\n", errcode, error_code(errcode));
2075 }
2076 if (n > 4)
2077 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2078
2079 break;
2080 }
2081 break;
2082 case 2: // protocol version
2083 {
2084 version = ntohs(*(uint16_t *) (b));
2085 LOG(4, s, t, " Protocol version = %d\n", version);
2086 if (version && version != 0x0100)
2087 { // allow 0.0 and 1.0
2088 LOG(1, s, t, " Bad protocol version %04X\n", version);
2089 fatal = flags;
2090 result = 5; // unspported protocol version
2091 error = 0x0100; // supported version
2092 msg = 0;
2093 continue; // next
2094 }
2095 }
2096 break;
2097 case 3: // framing capabilities
2098 // LOG(4, s, t, "Framing capabilities\n");
2099 break;
2100 case 4: // bearer capabilities
2101 // LOG(4, s, t, "Bearer capabilities\n");
2102 break;
2103 case 5: // tie breaker
2104 // We never open tunnels, so we don't care about tie breakers
2105 // LOG(4, s, t, "Tie breaker\n");
2106 continue;
2107 case 6: // firmware revision
2108 // LOG(4, s, t, "Firmware revision\n");
2109 break;
2110 case 7: // host name
2111 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2112 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2113 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2114 // TBA - to send to RADIUS
2115 break;
2116 case 8: // vendor name
2117 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2118 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2119 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2120 break;
2121 case 9: // assigned tunnel
2122 tunnel[t].far = ntohs(*(uint16_t *) (b));
2123 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2124 break;
2125 case 10: // rx window
2126 tunnel[t].window = ntohs(*(uint16_t *) (b));
2127 if (!tunnel[t].window)
2128 tunnel[t].window = 1; // window of 0 is silly
2129 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2130 break;
2131 case 11: // Challenge
2132 {
2133 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2134 build_chap_response(b, 2, n, &chapresponse);
2135 }
2136 break;
2137 case 13: // Response
2138 // Why did they send a response? We never challenge.
2139 LOG(2, s, t, " received unexpected challenge response\n");
2140 break;
2141
2142 case 14: // assigned session
2143 asession = session[s].far = ntohs(*(uint16_t *) (b));
2144 LOG(4, s, t, " assigned session = %d\n", asession);
2145 break;
2146 case 15: // call serial number
2147 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2148 break;
2149 case 18: // bearer type
2150 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2151 // TBA - for RADIUS
2152 break;
2153 case 19: // framing type
2154 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2155 // TBA
2156 break;
2157 case 21: // called number
2158 memset(called, 0, sizeof(called));
2159 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2160 LOG(4, s, t, " Called <%s>\n", called);
2161 break;
2162 case 22: // calling number
2163 memset(calling, 0, sizeof(calling));
2164 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2165 LOG(4, s, t, " Calling <%s>\n", calling);
2166 break;
2167 case 23: // subtype
2168 break;
2169 case 24: // tx connect speed
2170 if (n == 4)
2171 {
2172 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2173 }
2174 else
2175 {
2176 // AS5300s send connect speed as a string
2177 char tmp[30];
2178 memset(tmp, 0, sizeof(tmp));
2179 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2180 session[s].tx_connect_speed = atol(tmp);
2181 }
2182 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2183 break;
2184 case 38: // rx connect speed
2185 if (n == 4)
2186 {
2187 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2188 }
2189 else
2190 {
2191 // AS5300s send connect speed as a string
2192 char tmp[30];
2193 memset(tmp, 0, sizeof(tmp));
2194 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2195 session[s].rx_connect_speed = atol(tmp);
2196 }
2197 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2198 break;
2199 case 25: // Physical Channel ID
2200 {
2201 uint32_t tmp = ntohl(*(uint32_t *) b);
2202 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2203 break;
2204 }
2205 case 29: // Proxy Authentication Type
2206 {
2207 uint16_t atype = ntohs(*(uint16_t *)b);
2208 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
2209 if (atype == 2)
2210 authtype = AUTHCHAP;
2211 else if (atype == 3)
2212 authtype = AUTHPAP;
2213
2214 break;
2215 }
2216 case 30: // Proxy Authentication Name
2217 {
2218 char authname[64];
2219 memset(authname, 0, sizeof(authname));
2220 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2221 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2222 authname);
2223 break;
2224 }
2225 case 31: // Proxy Authentication Challenge
2226 {
2227 LOG(4, s, t, " Proxy Auth Challenge\n");
2228 if (sess_local[s].radius)
2229 memcpy(radius[sess_local[s].radius].auth, b, 16);
2230 break;
2231 }
2232 case 32: // Proxy Authentication ID
2233 {
2234 uint16_t authid = ntohs(*(uint16_t *)(b));
2235 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2236 if (sess_local[s].radius)
2237 radius[sess_local[s].radius].id = authid;
2238 break;
2239 }
2240 case 33: // Proxy Authentication Response
2241 LOG(4, s, t, " Proxy Auth Response\n");
2242 break;
2243 case 27: // last sent lcp
2244 { // find magic number
2245 uint8_t *p = b, *e = p + n;
2246 while (p + 1 < e && p[1] && p + p[1] <= e)
2247 {
2248 if (*p == 5 && p[1] == 6) // Magic-Number
2249 amagic = ntohl(*(uint32_t *) (p + 2));
2250 else if (*p == 3 && p[1] == 4 && *(uint16_t *) (p + 2) == htons(PPPPAP)) // Authentication-Protocol (PAP)
2251 authtype = AUTHPAP;
2252 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol (CHAP)
2253 authtype = AUTHCHAP;
2254 else if (*p == 7) // Protocol-Field-Compression
2255 aflags |= SESSIONPFC;
2256 else if (*p == 8) // Address-and-Control-Field-Compression
2257 aflags |= SESSIONACFC;
2258 p += p[1];
2259 }
2260 }
2261 break;
2262 case 28: // last recv lcp confreq
2263 break;
2264 case 26: // Initial Received LCP CONFREQ
2265 break;
2266 case 39: // seq required - we control it as an LNS anyway...
2267 break;
2268 case 36: // Random Vector
2269 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2270 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2271 if (n > sizeof(session[s].random_vector))
2272 n = sizeof(session[s].random_vector);
2273 memcpy(session[s].random_vector, b, n);
2274 session[s].random_vector_length = n;
2275 break;
2276 default:
2277 {
2278 static char e[] = "unknown AVP 0xXXXX";
2279 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2280 fatal = flags;
2281 result = 2; // general error
2282 error = 8; // unknown mandatory AVP
2283 sprintf((msg = e) + 14, "%04x", mtype);
2284 continue; // next
2285 }
2286 }
2287 }
2288 // process message
2289 if (fatal & 0x80)
2290 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2291 else
2292 switch (message)
2293 {
2294 case 1: // SCCRQ - Start Control Connection Request
2295 tunnel[t].state = TUNNELOPENING;
2296 if (main_quit != QUIT_SHUTDOWN)
2297 {
2298 controlt *c = controlnew(2); // sending SCCRP
2299 control16(c, 2, version, 1); // protocol version
2300 control32(c, 3, 3, 1); // framing
2301 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2302 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2303 control16(c, 9, t, 1); // assigned tunnel
2304 controladd(c, t, 0); // send the resply
2305 }
2306 else
2307 {
2308 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2309 }
2310 break;
2311 case 2: // SCCRP
2312 tunnel[t].state = TUNNELOPEN;
2313 break;
2314 case 3: // SCCN
2315 tunnel[t].state = TUNNELOPEN;
2316 controlnull(t); // ack
2317 break;
2318 case 4: // StopCCN
2319 controlnull(t); // ack
2320 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2321 break;
2322 case 6: // HELLO
2323 controlnull(t); // simply ACK
2324 break;
2325 case 7: // OCRQ
2326 // TBA
2327 break;
2328 case 8: // OCRO
2329 // TBA
2330 break;
2331 case 9: // OCCN
2332 // TBA
2333 break;
2334 case 10: // ICRQ
2335 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2336 {
2337 uint16_t r;
2338
2339 s = sessionfree;
2340 sessionfree = session[s].next;
2341 memset(&session[s], 0, sizeof(session[s]));
2342
2343 if (s > config->cluster_highest_sessionid)
2344 config->cluster_highest_sessionid = s;
2345
2346 // make a RADIUS session
2347 if ((r = radiusnew(s)))
2348 {
2349 controlt *c = controlnew(11); // sending ICRP
2350 session[s].opened = time_now;
2351 session[s].tunnel = t;
2352 session[s].far = asession;
2353 session[s].last_packet = time_now;
2354 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2355 control16(c, 14, s, 1); // assigned session
2356 controladd(c, t, asession); // send the reply
2357
2358 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
2359 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2360 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2361 STAT(session_created);
2362 break;
2363 }
2364
2365
2366 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
2367 sessionclear(s);
2368 }
2369 else
2370 {
2371 STAT(session_overflow);
2372 LOG(1, 0, t, "No free sessions\n");
2373 }
2374
2375 {
2376 controlt *c = controlnew(14); // CDN
2377 if (main_quit == QUIT_SHUTDOWN)
2378 control16(c, 1, 2, 7); // try another
2379 else
2380 control16(c, 1, 4, 0); // temporary lack of resources
2381
2382 controladd(c, t, asession); // send the message
2383 }
2384 return;
2385 case 11: // ICRP
2386 // TBA
2387 break;
2388 case 12: // ICCN
2389 if (amagic == 0) amagic = time_now;
2390 session[s].magic = amagic; // set magic number
2391 session[s].l2tp_flags = aflags; // set flags received
2392 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
2393 controlnull(t); // ack
2394 // proxy authentication type is not supported
2395 if (!(config->radius_authtypes & authtype))
2396 authtype = config->radius_authprefer;
2397
2398 // start LCP
2399 sendlcp(t, s, authtype);
2400 break;
2401 case 14: // CDN
2402 controlnull(t); // ack
2403 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2404 break;
2405 case 0xFFFF:
2406 LOG(1, s, t, "Missing message type\n");
2407 break;
2408 default:
2409 STAT(tunnel_rx_errors);
2410 if (mandatory)
2411 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2412 else
2413 LOG(1, s, t, "Unknown message type %d\n", message);
2414 break;
2415 }
2416 if (chapresponse) free(chapresponse);
2417 cluster_send_tunnel(t);
2418 }
2419 else
2420 {
2421 LOG(4, s, t, " Got a ZLB ack\n");
2422 }
2423 }
2424 else
2425 { // data
2426 uint16_t prot;
2427
2428 LOG_HEX(5, "Receive Tunnel Data", p, l);
2429 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2430 { // HDLC address header, discard
2431 p += 2;
2432 l -= 2;
2433 }
2434 if (l < 2)
2435 {
2436 LOG(1, s, t, "Short ppp length %d\n", l);
2437 STAT(tunnel_rx_errors);
2438 return;
2439 }
2440 if (*p & 1)
2441 {
2442 prot = *p++;
2443 l--;
2444 }
2445 else
2446 {
2447 prot = ntohs(*(uint16_t *) p);
2448 p += 2;
2449 l -= 2;
2450 }
2451
2452 if (s && !session[s].opened) // Is something wrong??
2453 {
2454 if (!config->cluster_iam_master)
2455 {
2456 // Pass it off to the master to deal with..
2457 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2458 return;
2459 }
2460
2461
2462 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2463 STAT(tunnel_rx_errors);
2464 return;
2465 }
2466
2467 if (prot == PPPPAP)
2468 {
2469 session[s].last_packet = time_now;
2470 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2471 processpap(t, s, p, l);
2472 }
2473 else if (prot == PPPCHAP)
2474 {
2475 session[s].last_packet = time_now;
2476 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2477 processchap(t, s, p, l);
2478 }
2479 else if (prot == PPPLCP)
2480 {
2481 session[s].last_packet = time_now;
2482 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2483 processlcp(t, s, p, l);
2484 }
2485 else if (prot == PPPIPCP)
2486 {
2487 session[s].last_packet = time_now;
2488 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2489 processipcp(t, s, p, l);
2490 }
2491 else if (prot == PPPIPV6CP)
2492 {
2493 if (config->ipv6_prefix.s6_addr[0] > 0)
2494 {
2495 session[s].last_packet = time_now;
2496 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2497 processipv6cp(t, s, p, l);
2498 }
2499 else
2500 {
2501 LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
2502 }
2503 }
2504 else if (prot == PPPCCP)
2505 {
2506 session[s].last_packet = time_now;
2507 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2508 processccp(t, s, p, l);
2509 }
2510 else if (prot == PPPIP)
2511 {
2512 if (session[s].die)
2513 {
2514 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2515 return; // closing session, PPP not processed
2516 }
2517
2518 session[s].last_packet = time_now;
2519 if (session[s].walled_garden && !config->cluster_iam_master)
2520 {
2521 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2522 return;
2523 }
2524
2525 processipin(t, s, p, l);
2526 }
2527 else if (prot == PPPIPV6)
2528 {
2529 if (!config->ipv6_prefix.s6_addr[0] > 0)
2530 {
2531 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2532 return;
2533 }
2534 if (session[s].die)
2535 {
2536 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2537 return; // closing session, PPP not processed
2538 }
2539
2540 session[s].last_packet = time_now;
2541 if (session[s].walled_garden && !config->cluster_iam_master)
2542 {
2543 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2544 return;
2545 }
2546
2547 processipv6in(t, s, p, l);
2548 }
2549 else
2550 {
2551 STAT(tunnel_rx_errors);
2552 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2553 }
2554 }
2555 }
2556
2557 // read and process packet on tun
2558 static void processtun(uint8_t * buf, int len)
2559 {
2560 LOG_HEX(5, "Receive TUN Data", buf, len);
2561 STAT(tun_rx_packets);
2562 INC_STAT(tun_rx_bytes, len);
2563
2564 CSTAT(processtun);
2565
2566 eth_rx_pkt++;
2567 eth_rx += len;
2568 if (len < 22)
2569 {
2570 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2571 STAT(tun_rx_errors);
2572 return;
2573 }
2574
2575 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2576 processipout(buf, len);
2577 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2578 && config->ipv6_prefix.s6_addr[0] > 0)
2579 processipv6out(buf, len);
2580
2581 // Else discard.
2582 }
2583
2584 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2585 // that we look at the whole of the tunnel, radius and session tables
2586 // every second
2587 static void regular_cleanups(double period)
2588 {
2589 // Next tunnel, radius and session to check for actions on.
2590 static tunnelidt t = 0;
2591 static int r = 0;
2592 static sessionidt s = 0;
2593
2594 int t_actions = 0;
2595 int r_actions = 0;
2596 int s_actions = 0;
2597
2598 int t_slice;
2599 int r_slice;
2600 int s_slice;
2601
2602 int i;
2603 int a;
2604
2605 // divide up tables into slices based on the last run
2606 t_slice = config->cluster_highest_tunnelid * period;
2607 r_slice = (MAXRADIUS - 1) * period;
2608 s_slice = config->cluster_highest_sessionid * period;
2609
2610 if (t_slice < 1)
2611 t_slice = 1;
2612 else if (t_slice > config->cluster_highest_tunnelid)
2613 t_slice = config->cluster_highest_tunnelid;
2614
2615 if (r_slice < 1)
2616 r_slice = 1;
2617 else if (r_slice > (MAXRADIUS - 1))
2618 r_slice = MAXRADIUS - 1;
2619
2620 if (s_slice < 1)
2621 s_slice = 1;
2622 else if (s_slice > config->cluster_highest_sessionid)
2623 s_slice = config->cluster_highest_sessionid;
2624
2625 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2626
2627 for (i = 0; i < t_slice; i++)
2628 {
2629 t++;
2630 if (t > config->cluster_highest_tunnelid)
2631 t = 1;
2632
2633 // check for expired tunnels
2634 if (tunnel[t].die && tunnel[t].die <= TIME)
2635 {
2636 STAT(tunnel_timeout);
2637 tunnelkill(t, "Expired");
2638 t_actions++;
2639 continue;
2640 }
2641 // check for message resend
2642 if (tunnel[t].retry && tunnel[t].controlc)
2643 {
2644 // resend pending messages as timeout on reply
2645 if (tunnel[t].retry <= TIME)
2646 {
2647 controlt *c = tunnel[t].controls;
2648 uint8_t w = tunnel[t].window;
2649 tunnel[t].try++; // another try
2650 if (tunnel[t].try > 5)
2651 tunnelkill(t, "Timeout on control message"); // game over
2652 else
2653 while (c && w--)
2654 {
2655 tunnelsend(c->buf, c->length, t);
2656 c = c->next;
2657 }
2658
2659 t_actions++;
2660 }
2661 }
2662 // Send hello
2663 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2664 {
2665 controlt *c = controlnew(6); // sending HELLO
2666 controladd(c, t, 0); // send the message
2667 LOG(3, 0, t, "Sending HELLO message\n");
2668 t_actions++;
2669 }
2670
2671 // Check for tunnel changes requested from the CLI
2672 if ((a = cli_tunnel_actions[t].action))
2673 {
2674 cli_tunnel_actions[t].action = 0;
2675 if (a & CLI_TUN_KILL)
2676 {
2677 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2678 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2679 t_actions++;
2680 }
2681 }
2682 }
2683
2684 for (i = 0; i < r_slice; i++)
2685 {
2686 r++;
2687 if (r >= MAXRADIUS)
2688 r = 1;
2689
2690 if (!radius[r].state)
2691 continue;
2692
2693 if (radius[r].retry <= TIME)
2694 {
2695 radiusretry(r);
2696 r_actions++;
2697 }
2698 }
2699
2700 for (i = 0; i < s_slice; i++)
2701 {
2702 s++;
2703 if (s > config->cluster_highest_sessionid)
2704 s = 1;
2705
2706 if (!session[s].opened) // Session isn't in use
2707 continue;
2708
2709 // check for expired sessions
2710 if (session[s].die)
2711 {
2712 if (session[s].die <= TIME)
2713 {
2714 sessionkill(s, "Expired");
2715 s_actions++;
2716 }
2717 continue;
2718 }
2719
2720 if (session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2721 {
2722 // IPCP has not completed yet. Resend
2723 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2724 sendipcp(session[s].tunnel, s);
2725 s_actions++;
2726 }
2727
2728 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2729 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2730 {
2731 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2732 STAT(session_timeout);
2733 s_actions++;
2734 continue;
2735 }
2736
2737 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2738 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2739 {
2740 uint8_t b[MAXCONTROL] = {0};
2741
2742 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2743 if (!q) continue;
2744
2745 *q = EchoReq;
2746 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2747 *(uint16_t *)(q + 2) = htons(8); // Length
2748 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2749
2750 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2751 (int)(time_now - session[s].last_packet));
2752 tunnelsend(b, 24, session[s].tunnel); // send it
2753 s_actions++;
2754 }
2755
2756 // Check for actions requested from the CLI
2757 if ((a = cli_session_actions[s].action))
2758 {
2759 int send = 0;
2760
2761 cli_session_actions[s].action = 0;
2762 if (a & CLI_SESS_KILL)
2763 {
2764 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2765 sessionshutdown(s, "Requested by administrator.", 3, 0);
2766 a = 0; // dead, no need to check for other actions
2767 s_actions++;
2768 }
2769
2770 if (a & CLI_SESS_NOSNOOP)
2771 {
2772 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2773 session[s].snoop_ip = 0;
2774 session[s].snoop_port = 0;
2775 s_actions++;
2776 send++;
2777 }
2778 else if (a & CLI_SESS_SNOOP)
2779 {
2780 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2781 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2782 cli_session_actions[s].snoop_port);
2783
2784 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2785 session[s].snoop_port = cli_session_actions[s].snoop_port;
2786 s_actions++;
2787 send++;
2788 }
2789
2790 if (a & CLI_SESS_NOTHROTTLE)
2791 {
2792 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2793 throttle_session(s, 0, 0);
2794 s_actions++;
2795 send++;
2796 }
2797 else if (a & CLI_SESS_THROTTLE)
2798 {
2799 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2800 cli_session_actions[s].throttle_in,
2801 cli_session_actions[s].throttle_out);
2802
2803 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2804 s_actions++;
2805 send++;
2806 }
2807
2808 if (a & CLI_SESS_NOFILTER)
2809 {
2810 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2811 filter_session(s, 0, 0);
2812 s_actions++;
2813 send++;
2814 }
2815 else if (a & CLI_SESS_FILTER)
2816 {
2817 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2818 cli_session_actions[s].filter_in,
2819 cli_session_actions[s].filter_out);
2820
2821 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2822 s_actions++;
2823 send++;
2824 }
2825
2826 if (send)
2827 cluster_send_session(s);
2828 }
2829
2830 // RADIUS interim accounting
2831 if (config->radius_accounting && config->radius_interim > 0
2832 && session[s].ip && !session[s].walled_garden
2833 && !sess_local[s].radius // RADIUS already in progress
2834 && time_now - sess_local[s].last_interim >= config->radius_interim)
2835 {
2836 if (!(r = radiusnew(s)))
2837 {
2838 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2839 STAT(radius_overflow);
2840 continue;
2841 }
2842
2843 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2844 session[s].user, session[s].unique_id);
2845
2846 radiussend(r, RADIUSINTERIM);
2847 sess_local[s].last_interim = time_now;
2848 s_actions++;
2849 }
2850 }
2851
2852 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
2853 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
2854 }
2855
2856 //
2857 // Are we in the middle of a tunnel update, or radius
2858 // requests??
2859 //
2860 static int still_busy(void)
2861 {
2862 int i;
2863 static clockt last_talked = 0;
2864 static clockt start_busy_wait = 0;
2865
2866 if (!config->cluster_iam_master)
2867 {
2868 #ifdef BGP
2869 static time_t stopped_bgp = 0;
2870 if (bgp_configured)
2871 {
2872 if (!stopped_bgp)
2873 {
2874 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
2875
2876 for (i = 0; i < BGP_NUM_PEERS; i++)
2877 if (bgp_peers[i].state == Established)
2878 bgp_stop(&bgp_peers[i]);
2879
2880 stopped_bgp = time_now;
2881
2882 // we don't want to become master
2883 cluster_send_ping(0);
2884
2885 return 1;
2886 }
2887
2888 if (time_now < (stopped_bgp + QUIT_DELAY))
2889 return 1;
2890 }
2891 #endif /* BGP */
2892
2893 return 0;
2894 }
2895
2896 if (main_quit == QUIT_SHUTDOWN)
2897 {
2898 static int dropped = 0;
2899 if (!dropped)
2900 {
2901 int i;
2902
2903 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
2904 for (i = 1; i < MAXTUNNEL; i++)
2905 if (tunnel[i].ip || tunnel[i].state)
2906 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
2907
2908 dropped = 1;
2909 }
2910 }
2911
2912 if (start_busy_wait == 0)
2913 start_busy_wait = TIME;
2914
2915 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2916 {
2917 if (!tunnel[i].controlc)
2918 continue;
2919
2920 if (last_talked != TIME)
2921 {
2922 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2923 last_talked = TIME;
2924 }
2925 return 1;
2926 }
2927
2928 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2929 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2930 {
2931 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2932 return 0;
2933 }
2934
2935 for (i = 1; i < MAXRADIUS; i++)
2936 {
2937 if (radius[i].state == RADIUSNULL)
2938 continue;
2939 if (radius[i].state == RADIUSWAIT)
2940 continue;
2941
2942 if (last_talked != TIME)
2943 {
2944 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2945 last_talked = TIME;
2946 }
2947 return 1;
2948 }
2949
2950 return 0;
2951 }
2952
2953 #ifdef HAVE_EPOLL
2954 # include <sys/epoll.h>
2955 #else
2956 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
2957 # include "fake_epoll.h"
2958 #endif
2959
2960 // the base set of fds polled: control, cli, udp, tun, cluster
2961 #define BASE_FDS 5
2962
2963 // additional polled fds
2964 #ifdef BGP
2965 # define EXTRA_FDS BGP_NUM_PEERS
2966 #else
2967 # define EXTRA_FDS 0
2968 #endif
2969
2970 // main loop - gets packets on tun or udp and processes them
2971 static void mainloop(void)
2972 {
2973 int i;
2974 uint8_t buf[65536];
2975 clockt next_cluster_ping = 0; // send initial ping immediately
2976 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
2977 int maxevent = sizeof(events)/sizeof(*events);
2978
2979 if ((epollfd = epoll_create(maxevent)) < 0)
2980 {
2981 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
2982 exit(1);
2983 }
2984
2985 LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2986 udpfd, tunfd, cluster_sockfd, controlfd);
2987
2988 /* setup our fds to poll for input */
2989 {
2990 static struct event_data d[BASE_FDS];
2991 struct epoll_event e;
2992
2993 e.events = EPOLLIN;
2994 i = 0;
2995
2996 d[i].type = FD_TYPE_CONTROL;
2997 e.data.ptr = &d[i++];
2998 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
2999
3000 d[i].type = FD_TYPE_CLI;
3001 e.data.ptr = &d[i++];
3002 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3003
3004 d[i].type = FD_TYPE_UDP;
3005 e.data.ptr = &d[i++];
3006 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3007
3008 d[i].type = FD_TYPE_TUN;
3009 e.data.ptr = &d[i++];
3010 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3011
3012 d[i].type = FD_TYPE_CLUSTER;
3013 e.data.ptr = &d[i++];
3014 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3015 }
3016
3017 #ifdef BGP
3018 signal(SIGPIPE, SIG_IGN);
3019 bgp_setup(config->as_number);
3020 if (config->bind_address)
3021 bgp_add_route(config->bind_address, 0xffffffff);
3022
3023 for (i = 0; i < BGP_NUM_PEERS; i++)
3024 {
3025 if (config->neighbour[i].name[0])
3026 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3027 config->neighbour[i].as, config->neighbour[i].keepalive,
3028 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3029 }
3030 #endif /* BGP */
3031
3032 while (!main_quit || still_busy())
3033 {
3034 int more = 0;
3035 int n;
3036
3037 if (config->reload_config)
3038 {
3039 // Update the config state based on config settings
3040 update_config();
3041 }
3042
3043 #ifdef BGP
3044 bgp_set_poll();
3045 #endif /* BGP */
3046
3047 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3048 STAT(select_called);
3049
3050 TIME = now(NULL);
3051 if (n < 0)
3052 {
3053 if (errno == EINTR ||
3054 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3055 continue;
3056
3057 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3058 break; // exit
3059 }
3060
3061 if (n)
3062 {
3063 struct sockaddr_in addr;
3064 int alen, c, s;
3065 int udp_ready = 0;
3066 int tun_ready = 0;
3067 int cluster_ready = 0;
3068 int udp_pkts = 0;
3069 int tun_pkts = 0;
3070 int cluster_pkts = 0;
3071 #ifdef BGP
3072 uint32_t bgp_events[BGP_NUM_PEERS];
3073 memset(bgp_events, 0, sizeof(bgp_events));
3074 #endif /* BGP */
3075
3076 for (c = n, i = 0; i < c; i++)
3077 {
3078 struct event_data *d = events[i].data.ptr;
3079 switch (d->type)
3080 {
3081 case FD_TYPE_CONTROL: // nsctl commands
3082 alen = sizeof(addr);
3083 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3084 n--;
3085 break;
3086
3087 case FD_TYPE_CLI: // CLI connections
3088 {
3089 int cli;
3090
3091 alen = sizeof(addr);
3092 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3093 {
3094 cli_do(cli);
3095 close(cli);
3096 }
3097 else
3098 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3099
3100 n--;
3101 break;
3102 }
3103
3104 // these are handled below, with multiple interleaved reads
3105 case FD_TYPE_UDP: udp_ready++; break;
3106 case FD_TYPE_TUN: tun_ready++; break;
3107 case FD_TYPE_CLUSTER: cluster_ready++; break;
3108
3109 case FD_TYPE_RADIUS: // RADIUS response
3110 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3111 if (s >= 0 && config->cluster_iam_master)
3112 processrad(buf, s, d->index);
3113
3114 n--;
3115 break;
3116
3117 #ifdef BGP
3118 case FD_TYPE_BGP:
3119 bgp_events[d->index] = events[i].events;
3120 n--;
3121 break;
3122 #endif /* BGP */
3123
3124 default:
3125 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3126 }
3127 }
3128
3129 #ifdef BGP
3130 bgp_process(bgp_events);
3131 #endif /* BGP */
3132
3133 for (c = 0; n && c < config->multi_read_count; c++)
3134 {
3135 // L2TP
3136 if (udp_ready)
3137 {
3138 alen = sizeof(addr);
3139 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3140 {
3141 processudp(buf, s, &addr);
3142 udp_pkts++;
3143 }
3144 else
3145 {
3146 udp_ready = 0;
3147 n--;
3148 }
3149 }
3150
3151 // incoming IP
3152 if (tun_ready)
3153 {
3154 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3155 {
3156 processtun(buf, s);
3157 tun_pkts++;
3158 }
3159 else
3160 {
3161 tun_ready = 0;
3162 n--;
3163 }
3164 }
3165
3166 // cluster
3167 if (cluster_ready)
3168 {
3169 alen = sizeof(addr);
3170 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3171 {
3172 processcluster(buf, s, addr.sin_addr.s_addr);
3173 cluster_pkts++;
3174 }
3175 else
3176 {
3177 cluster_ready = 0;
3178 n--;
3179 }
3180 }
3181 }
3182
3183 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3184 STAT(multi_read_used);
3185
3186 if (c >= config->multi_read_count)
3187 {
3188 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3189 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3190
3191 STAT(multi_read_exceeded);
3192 more++;
3193 }
3194 }
3195
3196 // Runs on every machine (master and slaves).
3197 if (next_cluster_ping <= TIME)
3198 {
3199 // Check to see which of the cluster is still alive..
3200
3201 cluster_send_ping(basetime); // Only does anything if we're a slave
3202 cluster_check_master(); // ditto.
3203
3204 cluster_heartbeat(); // Only does anything if we're a master.
3205 cluster_check_slaves(); // ditto.
3206
3207 master_update_counts(); // If we're a slave, send our byte counters to our master.
3208
3209 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3210 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3211 else
3212 next_cluster_ping = TIME + config->cluster_hb_interval;
3213 }
3214
3215 if (!config->cluster_iam_master)
3216 continue;
3217
3218 // Run token bucket filtering queue..
3219 // Only run it every 1/10th of a second.
3220 {
3221 static clockt last_run = 0;
3222 if (last_run != TIME)
3223 {
3224 last_run = TIME;
3225 tbf_run_timer();
3226 }
3227 }
3228
3229 // Handle timeouts, retries etc.
3230 {
3231 static double last_clean = 0;
3232 double this_clean;
3233 double diff;
3234
3235 TIME = now(&this_clean);
3236 diff = this_clean - last_clean;
3237
3238 // Run during idle time (after we've handled
3239 // all incoming packets) or every 1/10th sec
3240 if (!more || diff > 0.1)
3241 {
3242 regular_cleanups(diff);
3243 last_clean = this_clean;
3244 }
3245 }
3246
3247 if (*config->accounting_dir)
3248 {
3249 static clockt next_acct = 0;
3250 static clockt next_shut_acct = 0;
3251
3252 if (next_acct <= TIME)
3253 {
3254 // Dump accounting data
3255 next_acct = TIME + ACCT_TIME;
3256 next_shut_acct = TIME + ACCT_SHUT_TIME;
3257 dump_acct_info(1);
3258 }
3259 else if (next_shut_acct <= TIME)
3260 {
3261 // Dump accounting data for shutdown sessions
3262 next_shut_acct = TIME + ACCT_SHUT_TIME;
3263 if (shut_acct_n)
3264 dump_acct_info(0);
3265 }
3266 }
3267 }
3268
3269 // Are we the master and shutting down??
3270 if (config->cluster_iam_master)
3271 cluster_heartbeat(); // Flush any queued changes..
3272
3273 // Ok. Notify everyone we're shutting down. If we're
3274 // the master, this will force an election.
3275 cluster_send_ping(0);
3276
3277 //
3278 // Important!!! We MUST not process any packets past this point!
3279 LOG(1, 0, 0, "Shutdown complete\n");
3280 }
3281
3282 static void stripdomain(char *host)
3283 {
3284 char *p;
3285
3286 if ((p = strchr(host, '.')))
3287 {
3288 char *domain = 0;
3289 char _domain[1024];
3290
3291 // strip off domain
3292 FILE *resolv = fopen("/etc/resolv.conf", "r");
3293 if (resolv)
3294 {
3295 char buf[1024];
3296 char *b;
3297
3298 while (fgets(buf, sizeof(buf), resolv))
3299 {
3300 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3301 continue;
3302
3303 if (!isspace(buf[6]))
3304 continue;
3305
3306 b = buf + 7;
3307 while (isspace(*b)) b++;
3308
3309 if (*b)
3310 {
3311 char *d = b;
3312 while (*b && !isspace(*b)) b++;
3313 *b = 0;
3314 if (buf[0] == 'd') // domain is canonical
3315 {
3316 domain = d;
3317 break;
3318 }
3319
3320 // first search line
3321 if (!domain)
3322 {
3323 // hold, may be subsequent domain line
3324 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3325 domain = _domain;
3326 }
3327 }
3328 }
3329
3330 fclose(resolv);
3331 }
3332
3333 if (domain)
3334 {
3335 int hl = strlen(host);
3336 int dl = strlen(domain);
3337 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3338 host[hl -dl - 1] = 0;
3339 }
3340 else
3341 {
3342 *p = 0; // everything after first dot
3343 }
3344 }
3345 }
3346
3347 // Init data structures
3348 static void initdata(int optdebug, char *optconfig)
3349 {
3350 int i;
3351
3352 if (!(config = shared_malloc(sizeof(configt))))
3353 {
3354 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3355 exit(1);
3356 }
3357
3358 memset(config, 0, sizeof(configt));
3359 time(&config->start_time);
3360 strncpy(config->config_file, optconfig, strlen(optconfig));
3361 config->debug = optdebug;
3362 config->num_tbfs = MAXTBFS;
3363 config->rl_rate = 28; // 28kbps
3364 config->cluster_master_min_adv = 1;
3365 strcpy(config->random_device, RANDOMDEVICE);
3366
3367 log_stream = stderr;
3368
3369 #ifdef RINGBUFFER
3370 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3371 {
3372 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3373 exit(1);
3374 }
3375 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3376 #endif
3377
3378 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3379 {
3380 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3381 exit(1);
3382 }
3383 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3384 {
3385 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3386 exit(1);
3387 }
3388 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3389 {
3390 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3391 exit(1);
3392 }
3393
3394 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3395 {
3396 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3397 exit(1);
3398 }
3399
3400 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3401 {
3402 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3403 exit(1);
3404 }
3405
3406 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3407 {
3408 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3409 exit(1);
3410 }
3411
3412 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3413 {
3414 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3415 exit(1);
3416 }
3417 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3418
3419 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3420 {
3421 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3422 exit(1);
3423 }
3424 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3425
3426 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3427 {
3428 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3429 exit(1);
3430 }
3431 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3432
3433 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3434 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3435 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3436 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3437
3438 // Put all the sessions on the free list marked as undefined.
3439 for (i = 1; i < MAXSESSION; i++)
3440 {
3441 session[i].next = i + 1;
3442 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3443 }
3444 session[MAXSESSION - 1].next = 0;
3445 sessionfree = 1;
3446
3447 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3448 for (i = 1; i < MAXTUNNEL; i++)
3449 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3450
3451 if (!*hostname)
3452 {
3453 // Grab my hostname unless it's been specified
3454 gethostname(hostname, sizeof(hostname));
3455 stripdomain(hostname);
3456 }
3457
3458 _statistics->start_time = _statistics->last_reset = time(NULL);
3459
3460 #ifdef BGP
3461 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3462 {
3463 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3464 exit(1);
3465 }
3466 #endif /* BGP */
3467 }
3468
3469 static int assign_ip_address(sessionidt s)
3470 {
3471 uint32_t i;
3472 int best = -1;
3473 time_t best_time = time_now;
3474 char *u = session[s].user;
3475 char reuse = 0;
3476
3477
3478 CSTAT(assign_ip_address);
3479
3480 for (i = 1; i < ip_pool_size; i++)
3481 {
3482 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3483 continue;
3484
3485 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3486 {
3487 best = i;
3488 reuse = 1;
3489 break;
3490 }
3491
3492 if (ip_address_pool[i].last < best_time)
3493 {
3494 best = i;
3495 if (!(best_time = ip_address_pool[i].last))
3496 break; // never used, grab this one
3497 }
3498 }
3499
3500 if (best < 0)
3501 {
3502 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3503 return 0;
3504 }
3505
3506 session[s].ip = ip_address_pool[best].address;
3507 session[s].ip_pool_index = best;
3508 ip_address_pool[best].assigned = 1;
3509 ip_address_pool[best].last = time_now;
3510 ip_address_pool[best].session = s;
3511 if (session[s].walled_garden)
3512 /* Don't track addresses of users in walled garden (note: this
3513 means that their address isn't "sticky" even if they get
3514 un-gardened). */
3515 ip_address_pool[best].user[0] = 0;
3516 else
3517 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3518
3519 STAT(ip_allocated);
3520 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3521 reuse ? "Reusing" : "Allocating", best);
3522
3523 return 1;
3524 }
3525
3526 static void free_ip_address(sessionidt s)
3527 {
3528 int i = session[s].ip_pool_index;
3529
3530
3531 CSTAT(free_ip_address);
3532
3533 if (!session[s].ip)
3534 return; // what the?
3535
3536 if (i < 0) // Is this actually part of the ip pool?
3537 i = 0;
3538
3539 STAT(ip_freed);
3540 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3541 session[s].ip = 0;
3542 ip_address_pool[i].assigned = 0;
3543 ip_address_pool[i].session = 0;
3544 ip_address_pool[i].last = time_now;
3545 }
3546
3547 //
3548 // Fsck the address pool against the session table.
3549 // Normally only called when we become a master.
3550 //
3551 // This isn't perfect: We aren't keep tracking of which
3552 // users used to have an IP address.
3553 //
3554 void rebuild_address_pool(void)
3555 {
3556 int i;
3557
3558 //
3559 // Zero the IP pool allocation, and build
3560 // a map from IP address to pool index.
3561 for (i = 1; i < MAXIPPOOL; ++i)
3562 {
3563 ip_address_pool[i].assigned = 0;
3564 ip_address_pool[i].session = 0;
3565 if (!ip_address_pool[i].address)
3566 continue;
3567
3568 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3569 }
3570
3571 for (i = 0; i < MAXSESSION; ++i)
3572 {
3573 int ipid;
3574 if (!(session[i].opened && session[i].ip))
3575 continue;
3576
3577 ipid = - lookup_ipmap(htonl(session[i].ip));
3578
3579 if (session[i].ip_pool_index < 0)
3580 {
3581 // Not allocated out of the pool.
3582 if (ipid < 1) // Not found in the pool either? good.
3583 continue;
3584
3585 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3586 i, fmtaddr(session[i].ip, 0), ipid);
3587
3588 // Fall through and process it as part of the pool.
3589 }
3590
3591
3592 if (ipid > MAXIPPOOL || ipid < 0)
3593 {
3594 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3595 ipid = -1;
3596 session[i].ip_pool_index = ipid;
3597 continue;
3598 }
3599
3600 ip_address_pool[ipid].assigned = 1;
3601 ip_address_pool[ipid].session = i;
3602 ip_address_pool[ipid].last = time_now;
3603 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3604 session[i].ip_pool_index = ipid;
3605 cache_ipmap(session[i].ip, i); // Fix the ip map.
3606 }
3607 }
3608
3609 //
3610 // Fix the address pool to match a changed session.
3611 // (usually when the master sends us an update).
3612 static void fix_address_pool(int sid)
3613 {
3614 int ipid;
3615
3616 ipid = session[sid].ip_pool_index;
3617
3618 if (ipid > ip_pool_size)
3619 return; // Ignore it. rebuild_address_pool will fix it up.
3620
3621 if (ip_address_pool[ipid].address != session[sid].ip)
3622 return; // Just ignore it. rebuild_address_pool will take care of it.
3623
3624 ip_address_pool[ipid].assigned = 1;
3625 ip_address_pool[ipid].session = sid;
3626 ip_address_pool[ipid].last = time_now;
3627 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3628 }
3629
3630 //
3631 // Add a block of addresses to the IP pool to hand out.
3632 //
3633 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3634 {
3635 int i;
3636 if (mask == 0)
3637 mask = 0xffffffff; // Host route only.
3638
3639 addr &= mask;
3640
3641 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3642 return ;
3643
3644 for (i = addr ;(i & mask) == addr; ++i)
3645 {
3646 if ((i & 0xff) == 0 || (i&0xff) == 255)
3647 continue; // Skip 0 and broadcast addresses.
3648
3649 ip_address_pool[ip_pool_size].address = i;
3650 ip_address_pool[ip_pool_size].assigned = 0;
3651 ++ip_pool_size;
3652 if (ip_pool_size >= MAXIPPOOL)
3653 {
3654 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3655 return;
3656 }
3657 }
3658 }
3659
3660 // Initialize the IP address pool
3661 static void initippool()
3662 {
3663 FILE *f;
3664 char *p;
3665 char buf[4096];
3666 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3667
3668 if (!(f = fopen(IPPOOLFILE, "r")))
3669 {
3670 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3671 exit(1);
3672 }
3673
3674 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3675 {
3676 char *pool = buf;
3677 buf[4095] = 0; // Force it to be zero terminated/
3678
3679 if (*buf == '#' || *buf == '\n')
3680 continue; // Skip comments / blank lines
3681 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3682 if ((p = (char *)strchr(buf, ':')))
3683 {
3684 in_addr_t src;
3685 *p = '\0';
3686 src = inet_addr(buf);
3687 if (src == INADDR_NONE)
3688 {
3689 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3690 exit(1);
3691 }
3692 // This entry is for a specific IP only
3693 if (src != config->bind_address)
3694 continue;
3695 *p = ':';
3696 pool = p+1;
3697 }
3698 if ((p = (char *)strchr(pool, '/')))
3699 {
3700 // It's a range
3701 int numbits = 0;
3702 in_addr_t start = 0, mask = 0;
3703
3704 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3705 *p++ = 0;
3706 if (!*p || !(numbits = atoi(p)))
3707 {
3708 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3709 continue;
3710 }
3711 start = ntohl(inet_addr(pool));
3712 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3713
3714 // Add a static route for this pool
3715 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3716 fmtaddr(htonl(start), 0), 32 + mask);
3717
3718 routeset(0, start, mask, 0, 1);
3719
3720 add_to_ip_pool(start, mask);
3721 }
3722 else
3723 {
3724 // It's a single ip address
3725 add_to_ip_pool(inet_addr(pool), 0);
3726 }
3727 }
3728 fclose(f);
3729 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3730 }
3731
3732 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
3733 {
3734 struct sockaddr_in snoop_addr = {0};
3735 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3736 return;
3737
3738 snoop_addr.sin_family = AF_INET;
3739 snoop_addr.sin_addr.s_addr = destination;
3740 snoop_addr.sin_port = ntohs(port);
3741
3742 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3743 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3744 htons(snoop_addr.sin_port));
3745
3746 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3747 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3748
3749 STAT(packets_snooped);
3750 }
3751
3752 static int dump_session(FILE **f, sessiont *s)
3753 {
3754 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3755 return 1;
3756
3757 if (!*f)
3758 {
3759 char filename[1024];
3760 char timestr[64];
3761 time_t now = time(NULL);
3762
3763 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3764 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3765
3766 if (!(*f = fopen(filename, "w")))
3767 {
3768 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3769 return 0;
3770 }
3771
3772 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3773 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3774 "# host: %s\n"
3775 "# endpoint: %s\n"
3776 "# time: %ld\n"
3777 "# uptime: %ld\n"
3778 "# format: username ip qos uptxoctets downrxoctets\n",
3779 hostname,
3780 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3781 now,
3782 now - basetime);
3783 }
3784
3785 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3786 fprintf(*f, "%s %s %d %u %u\n",
3787 s->user, // username
3788 fmtaddr(htonl(s->ip), 0), // ip
3789 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3790 (uint32_t) s->cin_delta, // uptxoctets
3791 (uint32_t) s->cout_delta); // downrxoctets
3792
3793 s->cin_delta = s->cout_delta = 0;
3794
3795 return 1;
3796 }
3797
3798 static void dump_acct_info(int all)
3799 {
3800 int i;
3801 FILE *f = NULL;
3802
3803
3804 CSTAT(dump_acct_info);
3805
3806 if (shut_acct_n)
3807 {
3808 for (i = 0; i < shut_acct_n; i++)
3809 dump_session(&f, &shut_acct[i]);
3810
3811 shut_acct_n = 0;
3812 }
3813
3814 if (all)
3815 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3816 dump_session(&f, &session[i]);
3817
3818 if (f)
3819 fclose(f);
3820 }
3821
3822 // Main program
3823 int main(int argc, char *argv[])
3824 {
3825 int i;
3826 int optdebug = 0;
3827 char *optconfig = CONFIGFILE;
3828
3829 time(&basetime); // start clock
3830
3831 // scan args
3832 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3833 {
3834 switch (i)
3835 {
3836 case 'd':
3837 if (fork()) exit(0);
3838 setsid();
3839 freopen("/dev/null", "r", stdin);
3840 freopen("/dev/null", "w", stdout);
3841 freopen("/dev/null", "w", stderr);
3842 break;
3843 case 'v':
3844 optdebug++;
3845 break;
3846 case 'c':
3847 optconfig = optarg;
3848 break;
3849 case 'h':
3850 snprintf(hostname, sizeof(hostname), "%s", optarg);
3851 break;
3852 default:
3853 printf("Args are:\n"
3854 "\t-d\t\tDetach from terminal\n"
3855 "\t-c <file>\tConfig file\n"
3856 "\t-h <hostname>\tForce hostname\n"
3857 "\t-v\t\tDebug\n");
3858
3859 return (0);
3860 break;
3861 }
3862 }
3863
3864 // Start the timer routine off
3865 time(&time_now);
3866 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3867 signal(SIGALRM, sigalrm_handler);
3868 siginterrupt(SIGALRM, 0);
3869
3870 initplugins();
3871 initdata(optdebug, optconfig);
3872
3873 init_cli(hostname);
3874 read_config_file();
3875 init_tbf(config->num_tbfs);
3876
3877 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3878 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3879 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3880 {
3881 struct rlimit rlim;
3882 rlim.rlim_cur = RLIM_INFINITY;
3883 rlim.rlim_max = RLIM_INFINITY;
3884 // Remove the maximum core size
3885 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3886 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3887
3888 // Make core dumps go to /tmp
3889 chdir("/tmp");
3890 }
3891
3892 if (config->scheduler_fifo)
3893 {
3894 int ret;
3895 struct sched_param params = {0};
3896 params.sched_priority = 1;
3897
3898 if (get_nprocs() < 2)
3899 {
3900 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3901 config->scheduler_fifo = 0;
3902 }
3903 else
3904 {
3905 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3906 {
3907 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3908 }
3909 else
3910 {
3911 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3912 config->scheduler_fifo = 0;
3913 }
3914 }
3915 }
3916
3917 /* Set up the cluster communications port. */
3918 if (cluster_init() < 0)
3919 exit(1);
3920
3921 inittun();
3922 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3923
3924 initudp();
3925 initrad();
3926 initippool();
3927
3928 // seed prng
3929 {
3930 unsigned seed = time_now ^ getpid();
3931 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
3932 srand(seed);
3933 }
3934
3935 signal(SIGHUP, sighup_handler);
3936 signal(SIGCHLD, sigchild_handler);
3937 signal(SIGTERM, shutdown_handler);
3938 signal(SIGINT, shutdown_handler);
3939 signal(SIGQUIT, shutdown_handler);
3940
3941 // Prevent us from getting paged out
3942 if (config->lock_pages)
3943 {
3944 if (!mlockall(MCL_CURRENT))
3945 LOG(1, 0, 0, "Locking pages into memory\n");
3946 else
3947 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3948 }
3949
3950 alarm(1);
3951
3952 // Drop privileges here
3953 if (config->target_uid > 0 && geteuid() == 0)
3954 setuid(config->target_uid);
3955
3956 mainloop();
3957
3958 /* remove plugins (so cleanup code gets run) */
3959 plugins_done();
3960
3961 // Remove the PID file if we wrote it
3962 if (config->wrote_pid && *config->pid_file == '/')
3963 unlink(config->pid_file);
3964
3965 /* kill CLI children */
3966 signal(SIGTERM, SIG_IGN);
3967 kill(0, SIGTERM);
3968 return 0;
3969 }
3970
3971 static void sighup_handler(int sig)
3972 {
3973 if (log_stream)
3974 {
3975 if (log_stream != stderr)
3976 fclose(log_stream);
3977
3978 log_stream = NULL;
3979 }
3980
3981 read_config_file();
3982 }
3983
3984 static void sigalrm_handler(int sig)
3985 {
3986 // Log current traffic stats
3987
3988 snprintf(config->bandwidth, sizeof(config->bandwidth),
3989 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3990 (udp_rx / 1024.0 / 1024.0 * 8),
3991 (eth_tx / 1024.0 / 1024.0 * 8),
3992 (eth_rx / 1024.0 / 1024.0 * 8),
3993 (udp_tx / 1024.0 / 1024.0 * 8),
3994 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3995 udp_rx_pkt, eth_rx_pkt);
3996
3997 udp_tx = udp_rx = 0;
3998 udp_rx_pkt = eth_rx_pkt = 0;
3999 eth_tx = eth_rx = 0;
4000
4001 if (config->dump_speed)
4002 printf("%s\n", config->bandwidth);
4003
4004 // Update the internal time counter
4005 time(&time_now);
4006 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4007 alarm(1);
4008
4009 {
4010 // Run timer hooks
4011 struct param_timer p = { time_now };
4012 run_plugins(PLUGIN_TIMER, &p);
4013 }
4014
4015 }
4016
4017 static void shutdown_handler(int sig)
4018 {
4019 LOG(1, 0, 0, "Shutting down\n");
4020 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4021 }
4022
4023 static void sigchild_handler(int sig)
4024 {
4025 while (waitpid(-1, NULL, WNOHANG) > 0)
4026 ;
4027 }
4028
4029 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
4030 {
4031 MD5_CTX ctx;
4032 *challenge_response = NULL;
4033
4034 if (!*config->l2tpsecret)
4035 {
4036 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4037 return;
4038 }
4039
4040 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4041
4042 *challenge_response = (char *)calloc(17, 1);
4043
4044 MD5Init(&ctx);
4045 MD5Update(&ctx, &id, 1);
4046 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4047 MD5Update(&ctx, challenge, challenge_length);
4048 MD5Final(*challenge_response, &ctx);
4049
4050 return;
4051 }
4052
4053 static int facility_value(char *name)
4054 {
4055 int i;
4056 for (i = 0; facilitynames[i].c_name; i++)
4057 {
4058 if (strcmp(facilitynames[i].c_name, name) == 0)
4059 return facilitynames[i].c_val;
4060 }
4061 return 0;
4062 }
4063
4064 static void update_config()
4065 {
4066 int i;
4067 char *p;
4068 static int timeout = 0;
4069 static int interval = 0;
4070
4071 // Update logging
4072 closelog();
4073 syslog_log = 0;
4074 if (log_stream)
4075 {
4076 if (log_stream != stderr)
4077 fclose(log_stream);
4078
4079 log_stream = NULL;
4080 }
4081
4082 if (*config->log_filename)
4083 {
4084 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4085 {
4086 char *p = config->log_filename + 7;
4087 if (*p)
4088 {
4089 openlog("l2tpns", LOG_PID, facility_value(p));
4090 syslog_log = 1;
4091 }
4092 }
4093 else if (strchr(config->log_filename, '/') == config->log_filename)
4094 {
4095 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4096 {
4097 fseek(log_stream, 0, SEEK_END);
4098 setbuf(log_stream, NULL);
4099 }
4100 else
4101 {
4102 log_stream = stderr;
4103 setbuf(log_stream, NULL);
4104 }
4105 }
4106 }
4107 else
4108 {
4109 log_stream = stderr;
4110 setbuf(log_stream, NULL);
4111 }
4112
4113 // Update radius
4114 config->numradiusservers = 0;
4115 for (i = 0; i < MAXRADSERVER; i++)
4116 if (config->radiusserver[i])
4117 {
4118 config->numradiusservers++;
4119 // Set radius port: if not set, take the port from the
4120 // first radius server. For the first radius server,
4121 // take the #defined default value from l2tpns.h
4122
4123 // test twice, In case someone works with
4124 // a secondary radius server without defining
4125 // a primary one, this will work even then.
4126 if (i > 0 && !config->radiusport[i])
4127 config->radiusport[i] = config->radiusport[i-1];
4128 if (!config->radiusport[i])
4129 config->radiusport[i] = RADPORT;
4130 }
4131
4132 if (!config->numradiusservers)
4133 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4134
4135 // parse radius_authtypes_s
4136 config->radius_authtypes = config->radius_authprefer = 0;
4137 p = config->radius_authtypes_s;
4138 while (p && *p)
4139 {
4140 char *s = strpbrk(p, " \t,");
4141 int type = 0;
4142
4143 if (s)
4144 {
4145 *s++ = 0;
4146 while (*s == ' ' || *s == '\t')
4147 s++;
4148
4149 if (!*s)
4150 s = 0;
4151 }
4152
4153 if (!strncasecmp("chap", p, strlen(p)))
4154 type = AUTHCHAP;
4155 else if (!strncasecmp("pap", p, strlen(p)))
4156 type = AUTHPAP;
4157 else
4158 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4159
4160 config->radius_authtypes |= type;
4161 if (!config->radius_authprefer)
4162 config->radius_authprefer = type;
4163
4164 p = s;
4165 }
4166
4167 if (!config->radius_authtypes)
4168 {
4169 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4170 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4171 }
4172
4173 // normalise radius_authtypes_s
4174 if (config->radius_authprefer == AUTHPAP)
4175 {
4176 strcpy(config->radius_authtypes_s, "pap");
4177 if (config->radius_authtypes & AUTHCHAP)
4178 strcat(config->radius_authtypes_s, ", chap");
4179 }
4180 else
4181 {
4182 strcpy(config->radius_authtypes_s, "chap");
4183 if (config->radius_authtypes & AUTHPAP)
4184 strcat(config->radius_authtypes_s, ", pap");
4185 }
4186
4187 // re-initialise the random number source
4188 initrandom(config->random_device);
4189
4190 // Update plugins
4191 for (i = 0; i < MAXPLUGINS; i++)
4192 {
4193 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4194 continue;
4195
4196 if (*config->plugins[i])
4197 {
4198 // Plugin added
4199 add_plugin(config->plugins[i]);
4200 }
4201 else if (*config->old_plugins[i])
4202 {
4203 // Plugin removed
4204 remove_plugin(config->old_plugins[i]);
4205 }
4206 }
4207
4208 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4209 if (!config->multi_read_count) config->multi_read_count = 10;
4210 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4211 if (!*config->cluster_interface)
4212 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4213
4214 if (!config->cluster_hb_interval)
4215 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4216
4217 if (!config->cluster_hb_timeout)
4218 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4219
4220 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4221 {
4222 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4223 // late, ensure we're sufficiently larger than that
4224 int t = 4 * config->cluster_hb_interval + 11;
4225
4226 if (config->cluster_hb_timeout < t)
4227 {
4228 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4229 config->cluster_hb_timeout = t;
4230 }
4231
4232 // Push timing changes to the slaves immediately if we're the master
4233 if (config->cluster_iam_master)
4234 cluster_heartbeat();
4235
4236 interval = config->cluster_hb_interval;
4237 timeout = config->cluster_hb_timeout;
4238 }
4239
4240 // Write PID file
4241 if (*config->pid_file == '/' && !config->wrote_pid)
4242 {
4243 FILE *f;
4244 if ((f = fopen(config->pid_file, "w")))
4245 {
4246 fprintf(f, "%d\n", getpid());
4247 fclose(f);
4248 config->wrote_pid = 1;
4249 }
4250 else
4251 {
4252 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4253 }
4254 }
4255
4256 config->reload_config = 0;
4257 }
4258
4259 static void read_config_file()
4260 {
4261 FILE *f;
4262
4263 if (!config->config_file) return;
4264 if (!(f = fopen(config->config_file, "r")))
4265 {
4266 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4267 return;
4268 }
4269
4270 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4271 cli_do_file(f);
4272 LOG(3, 0, 0, "Done reading config file\n");
4273 fclose(f);
4274 update_config();
4275 }
4276
4277 int sessionsetup(tunnelidt t, sessionidt s)
4278 {
4279 // A session now exists, set it up
4280 in_addr_t ip;
4281 char *user;
4282 sessionidt i;
4283 int r;
4284
4285 CSTAT(sessionsetup);
4286
4287 LOG(3, s, t, "Doing session setup for session\n");
4288
4289 if (!session[s].ip)
4290 {
4291 assign_ip_address(s);
4292 if (!session[s].ip)
4293 {
4294 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4295 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4296 return 0;
4297 }
4298 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4299 fmtaddr(htonl(session[s].ip), 0));
4300 }
4301
4302
4303 // Make sure this is right
4304 session[s].tunnel = t;
4305
4306 // zap old sessions with same IP and/or username
4307 // Don't kill gardened sessions - doing so leads to a DoS
4308 // from someone who doesn't need to know the password
4309 {
4310 ip = session[s].ip;
4311 user = session[s].user;
4312 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4313 {
4314 if (i == s) continue;
4315 if (!session[s].opened) continue;
4316 if (ip == session[i].ip)
4317 {
4318 sessionkill(i, "Duplicate IP address");
4319 continue;
4320 }
4321
4322 if (config->allow_duplicate_users) continue;
4323 if (session[s].walled_garden || session[i].walled_garden) continue;
4324 if (!strcasecmp(user, session[i].user))
4325 sessionkill(i, "Duplicate session for users");
4326 }
4327 }
4328
4329 {
4330 int routed = 0;
4331
4332 // Add the route for this session.
4333 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4334 {
4335 if ((session[s].ip & session[s].route[r].mask) ==
4336 (session[s].route[r].ip & session[s].route[r].mask))
4337 routed++;
4338
4339 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4340 }
4341
4342 // Static IPs need to be routed if not already
4343 // convered by a Framed-Route. Anything else is part
4344 // of the IP address pool and is already routed, it
4345 // just needs to be added to the IP cache.
4346 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4347 if (session[s].ip_pool_index == -1) // static ip
4348 {
4349 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4350 }
4351 else
4352 cache_ipmap(session[s].ip, s);
4353 }
4354
4355 if (!session[s].unique_id)
4356 {
4357 // did this session just finish radius?
4358 LOG(3, s, t, "Sending initial IPCP to client\n");
4359 sendipcp(t, s);
4360 session[s].unique_id = ++last_id;
4361 }
4362
4363 // Run the plugin's against this new session.
4364 {
4365 struct param_new_session data = { &tunnel[t], &session[s] };
4366 run_plugins(PLUGIN_NEW_SESSION, &data);
4367 }
4368
4369 // Allocate TBFs if throttled
4370 if (session[s].throttle_in || session[s].throttle_out)
4371 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4372
4373 session[s].last_packet = time_now;
4374
4375 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4376 fmtaddr(htonl(session[s].ip), 0),
4377 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4378
4379 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4380
4381 return 1; // RADIUS OK and IP allocated, done...
4382 }
4383
4384 //
4385 // This session just got dropped on us by the master or something.
4386 // Make sure our tables up up to date...
4387 //
4388 int load_session(sessionidt s, sessiont *new)
4389 {
4390 int i;
4391 int newip = 0;
4392
4393 // Sanity checks.
4394 if (new->ip_pool_index >= MAXIPPOOL ||
4395 new->tunnel >= MAXTUNNEL)
4396 {
4397 LOG(0, s, 0, "Strange session update received!\n");
4398 // FIXME! What to do here?
4399 return 0;
4400 }
4401
4402 //
4403 // Ok. All sanity checks passed. Now we're committed to
4404 // loading the new session.
4405 //
4406
4407 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4408
4409 // See if routes/ip cache need updating
4410 if (new->ip != session[s].ip)
4411 newip++;
4412
4413 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4414 if (new->route[i].ip != session[s].route[i].ip ||
4415 new->route[i].mask != session[s].route[i].mask)
4416 newip++;
4417
4418 // needs update
4419 if (newip)
4420 {
4421 int routed = 0;
4422
4423 // remove old routes...
4424 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4425 {
4426 if ((session[s].ip & session[s].route[i].mask) ==
4427 (session[s].route[i].ip & session[s].route[i].mask))
4428 routed++;
4429
4430 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4431 }
4432
4433 // ...ip
4434 if (session[s].ip)
4435 {
4436 if (session[s].ip_pool_index == -1) // static IP
4437 {
4438 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4439 }
4440 else // It's part of the IP pool, remove it manually.
4441 uncache_ipmap(session[s].ip);
4442 }
4443
4444 routed = 0;
4445
4446 // add new routes...
4447 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4448 {
4449 if ((new->ip & new->route[i].mask) ==
4450 (new->route[i].ip & new->route[i].mask))
4451 routed++;
4452
4453 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4454 }
4455
4456 // ...ip
4457 if (new->ip)
4458 {
4459 // If there's a new one, add it.
4460 if (new->ip_pool_index == -1)
4461 {
4462 if (!routed) routeset(s, new->ip, 0, 0, 1);
4463 }
4464 else
4465 cache_ipmap(new->ip, s);
4466 }
4467 }
4468
4469 // check v6 routing
4470 if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
4471 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4472
4473 // check filters
4474 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4475 {
4476 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4477 new->filter_in = 0;
4478 }
4479
4480 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4481 {
4482 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4483 new->filter_out = 0;
4484 }
4485
4486 if (new->filter_in != session[s].filter_in)
4487 {
4488 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4489 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4490 }
4491
4492 if (new->filter_out != session[s].filter_out)
4493 {
4494 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4495 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4496 }
4497
4498 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4499 // for walking the sessions to forward byte counts to the master.
4500 config->cluster_highest_sessionid = s;
4501
4502 // TEMP: old session struct used a uint32_t to define the throttle
4503 // speed for both up/down, new uses a uint16_t for each. Deal with
4504 // sessions from an old master for migration.
4505 if (new->throttle_out == 0 && new->tbf_out)
4506 new->throttle_out = new->throttle_in;
4507
4508 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4509
4510 // Do fixups into address pool.
4511 if (new->ip_pool_index != -1)
4512 fix_address_pool(s);
4513
4514 return 1;
4515 }
4516
4517 static void initplugins()
4518 {
4519 int i;
4520
4521 loaded_plugins = ll_init();
4522 // Initialize the plugins to nothing
4523 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4524 plugins[i] = ll_init();
4525 }
4526
4527 static void *open_plugin(char *plugin_name, int load)
4528 {
4529 char path[256] = "";
4530
4531 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4532 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4533 return dlopen(path, RTLD_NOW);
4534 }
4535
4536 // plugin callback to get a config value
4537 static void *getconfig(char *key, enum config_typet type)
4538 {
4539 int i;
4540
4541 for (i = 0; config_values[i].key; i++)
4542 {
4543 if (!strcmp(config_values[i].key, key))
4544 {
4545 if (config_values[i].type == type)
4546 return ((void *) config) + config_values[i].offset;
4547
4548 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4549 key, type, config_values[i].type);
4550
4551 return 0;
4552 }
4553 }
4554
4555 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4556 return 0;
4557 }
4558
4559 static int add_plugin(char *plugin_name)
4560 {
4561 static struct pluginfuncs funcs = {
4562 _log,
4563 _log_hex,
4564 fmtaddr,
4565 sessionbyuser,
4566 sessiontbysessionidt,
4567 sessionidtbysessiont,
4568 radiusnew,
4569 radiussend,
4570 getconfig,
4571 sessionshutdown,
4572 sessionkill,
4573 throttle_session,
4574 cluster_send_session,
4575 };
4576
4577 void *p = open_plugin(plugin_name, 1);
4578 int (*initfunc)(struct pluginfuncs *);
4579 int i;
4580
4581 if (!p)
4582 {
4583 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4584 return -1;
4585 }
4586
4587 if (ll_contains(loaded_plugins, p))
4588 {
4589 dlclose(p);
4590 return 0; // already loaded
4591 }
4592
4593 {
4594 int *v = dlsym(p, "plugin_api_version");
4595 if (!v || *v != PLUGIN_API_VERSION)
4596 {
4597 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4598 dlclose(p);
4599 return -1;
4600 }
4601 }
4602
4603 if ((initfunc = dlsym(p, "plugin_init")))
4604 {
4605 if (!initfunc(&funcs))
4606 {
4607 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4608 dlclose(p);
4609 return -1;
4610 }
4611 }
4612
4613 ll_push(loaded_plugins, p);
4614
4615 for (i = 0; i < max_plugin_functions; i++)
4616 {
4617 void *x;
4618 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4619 {
4620 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4621 ll_push(plugins[i], x);
4622 }
4623 }
4624
4625 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4626 return 1;
4627 }
4628
4629 static void run_plugin_done(void *plugin)
4630 {
4631 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4632
4633 if (donefunc)
4634 donefunc();
4635 }
4636
4637 static int remove_plugin(char *plugin_name)
4638 {
4639 void *p = open_plugin(plugin_name, 0);
4640 int loaded = 0;
4641
4642 if (!p)
4643 return -1;
4644
4645 if (ll_contains(loaded_plugins, p))
4646 {
4647 int i;
4648 for (i = 0; i < max_plugin_functions; i++)
4649 {
4650 void *x;
4651 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4652 ll_delete(plugins[i], x);
4653 }
4654
4655 ll_delete(loaded_plugins, p);
4656 run_plugin_done(p);
4657 loaded = 1;
4658 }
4659
4660 dlclose(p);
4661 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4662 return loaded;
4663 }
4664
4665 int run_plugins(int plugin_type, void *data)
4666 {
4667 int (*func)(void *data);
4668
4669 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4670 return PLUGIN_RET_ERROR;
4671
4672 ll_reset(plugins[plugin_type]);
4673 while ((func = ll_next(plugins[plugin_type])))
4674 {
4675 int r = func(data);
4676
4677 if (r != PLUGIN_RET_OK)
4678 return r; // stop here
4679 }
4680
4681 return PLUGIN_RET_OK;
4682 }
4683
4684 static void plugins_done()
4685 {
4686 void *p;
4687
4688 ll_reset(loaded_plugins);
4689 while ((p = ll_next(loaded_plugins)))
4690 run_plugin_done(p);
4691 }
4692
4693 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4694 {
4695 struct nsctl request;
4696 struct nsctl response;
4697 int type = unpack_control(&request, buf, len);
4698 int r;
4699 void *p;
4700
4701 if (log_stream && config->debug >= 4)
4702 {
4703 if (type < 0)
4704 {
4705 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4706 fmtaddr(addr->sin_addr.s_addr, 0), type);
4707 }
4708 else
4709 {
4710 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4711 dump_control(&request, log_stream);
4712 }
4713 }
4714
4715 switch (type)
4716 {
4717 case NSCTL_REQ_LOAD:
4718 if (request.argc != 1)
4719 {
4720 response.type = NSCTL_RES_ERR;
4721 response.argc = 1;
4722 response.argv[0] = "name of plugin required";
4723 }
4724 else if ((r = add_plugin(request.argv[0])) < 1)
4725 {
4726 response.type = NSCTL_RES_ERR;
4727 response.argc = 1;
4728 response.argv[0] = !r
4729 ? "plugin already loaded"
4730 : "error loading plugin";
4731 }
4732 else
4733 {
4734 response.type = NSCTL_RES_OK;
4735 response.argc = 0;
4736 }
4737
4738 break;
4739
4740 case NSCTL_REQ_UNLOAD:
4741 if (request.argc != 1)
4742 {
4743 response.type = NSCTL_RES_ERR;
4744 response.argc = 1;
4745 response.argv[0] = "name of plugin required";
4746 }
4747 else if ((r = remove_plugin(request.argv[0])) < 1)
4748 {
4749 response.type = NSCTL_RES_ERR;
4750 response.argc = 1;
4751 response.argv[0] = !r
4752 ? "plugin not loaded"
4753 : "plugin not found";
4754 }
4755 else
4756 {
4757 response.type = NSCTL_RES_OK;
4758 response.argc = 0;
4759 }
4760
4761 break;
4762
4763 case NSCTL_REQ_HELP:
4764 response.type = NSCTL_RES_OK;
4765 response.argc = 0;
4766
4767 ll_reset(loaded_plugins);
4768 while ((p = ll_next(loaded_plugins)))
4769 {
4770 char **help = dlsym(p, "plugin_control_help");
4771 while (response.argc < 0xff && help && *help)
4772 response.argv[response.argc++] = *help++;
4773 }
4774
4775 break;
4776
4777 case NSCTL_REQ_CONTROL:
4778 {
4779 struct param_control param = {
4780 config->cluster_iam_master,
4781 request.argc,
4782 request.argv,
4783 0,
4784 NULL,
4785 };
4786
4787 int r = run_plugins(PLUGIN_CONTROL, &param);
4788
4789 if (r == PLUGIN_RET_ERROR)
4790 {
4791 response.type = NSCTL_RES_ERR;
4792 response.argc = 1;
4793 response.argv[0] = param.additional
4794 ? param.additional
4795 : "error returned by plugin";
4796 }
4797 else if (r == PLUGIN_RET_NOTMASTER)
4798 {
4799 static char msg[] = "must be run on master: 000.000.000.000";
4800
4801 response.type = NSCTL_RES_ERR;
4802 response.argc = 1;
4803 if (config->cluster_master_address)
4804 {
4805 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4806 response.argv[0] = msg;
4807 }
4808 else
4809 {
4810 response.argv[0] = "must be run on master: none elected";
4811 }
4812 }
4813 else if (!(param.response & NSCTL_RESPONSE))
4814 {
4815 response.type = NSCTL_RES_ERR;
4816 response.argc = 1;
4817 response.argv[0] = param.response
4818 ? "unrecognised response value from plugin"
4819 : "unhandled action";
4820 }
4821 else
4822 {
4823 response.type = param.response;
4824 response.argc = 0;
4825 if (param.additional)
4826 {
4827 response.argc = 1;
4828 response.argv[0] = param.additional;
4829 }
4830 }
4831 }
4832
4833 break;
4834
4835 default:
4836 response.type = NSCTL_RES_ERR;
4837 response.argc = 1;
4838 response.argv[0] = "error unpacking control packet";
4839 }
4840
4841 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4842 if (!buf)
4843 {
4844 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4845 return;
4846 }
4847
4848 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4849 if (r > 0)
4850 {
4851 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4852 if (log_stream && config->debug >= 4)
4853 {
4854 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4855 dump_control(&response, log_stream);
4856 }
4857 }
4858 else
4859 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4860 fmtaddr(addr->sin_addr.s_addr, 0), r);
4861
4862 free(buf);
4863 }
4864
4865 static tunnelidt new_tunnel()
4866 {
4867 tunnelidt i;
4868 for (i = 1; i < MAXTUNNEL; i++)
4869 {
4870 if (tunnel[i].state == TUNNELFREE)
4871 {
4872 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4873 if (i > config->cluster_highest_tunnelid)
4874 config->cluster_highest_tunnelid = i;
4875 return i;
4876 }
4877 }
4878 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4879 return 0;
4880 }
4881
4882 //
4883 // We're becoming the master. Do any required setup..
4884 //
4885 // This is principally telling all the plugins that we're
4886 // now a master, and telling them about all the sessions
4887 // that are active too..
4888 //
4889 void become_master(void)
4890 {
4891 int s, i;
4892 static struct event_data d[RADIUS_FDS];
4893 struct epoll_event e;
4894
4895 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4896
4897 // running a bunch of iptables commands is slow and can cause
4898 // the master to drop tunnels on takeover--kludge around the
4899 // problem by forking for the moment (note: race)
4900 if (!fork_and_close())
4901 {
4902 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4903 {
4904 if (!session[s].opened) // Not an in-use session.
4905 continue;
4906
4907 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4908 }
4909 exit(0);
4910 }
4911
4912 // add radius fds
4913 e.events = EPOLLIN;
4914 for (i = 0; i < RADIUS_FDS; i++)
4915 {
4916 d[i].type = FD_TYPE_RADIUS;
4917 d[i].index = i;
4918 e.data.ptr = &d[i];
4919
4920 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
4921 }
4922 }
4923
4924 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4925 {
4926 int s, i;
4927 int count = 0;
4928 int buckets[64];
4929
4930 if (CLI_HELP_REQUESTED)
4931 return CLI_HELP_NO_ARGS;
4932
4933 time(&time_now);
4934 for (i = 0; i < 64;++i) buckets[i] = 0;
4935
4936 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4937 {
4938 int idle;
4939 if (!session[s].opened)
4940 continue;
4941
4942 idle = time_now - session[s].last_packet;
4943 idle /= 5 ; // In multiples of 5 seconds.
4944 if (idle < 0)
4945 idle = 0;
4946 if (idle > 63)
4947 idle = 63;
4948
4949 ++count;
4950 ++buckets[idle];
4951 }
4952
4953 for (i = 0; i < 63; ++i)
4954 {
4955 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4956 }
4957 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4958 cli_print(cli, "%d total sessions open.", count);
4959 return CLI_OK;
4960 }
4961
4962 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4963 {
4964 int s, i;
4965 int count = 0;
4966 int buckets[64];
4967
4968 if (CLI_HELP_REQUESTED)
4969 return CLI_HELP_NO_ARGS;
4970
4971 time(&time_now);
4972 for (i = 0; i < 64;++i) buckets[i] = 0;
4973
4974 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4975 {
4976 int open = 0, d;
4977 if (!session[s].opened)
4978 continue;
4979
4980 d = time_now - session[s].opened;
4981 if (d < 0)
4982 d = 0;
4983 while (d > 1 && open < 32)
4984 {
4985 ++open;
4986 d >>= 1; // half.
4987 }
4988 ++count;
4989 ++buckets[open];
4990 }
4991
4992 s = 1;
4993 for (i = 0; i < 30; ++i)
4994 {
4995 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4996 s <<= 1;
4997 }
4998 cli_print(cli, "%d total sessions open.", count);
4999 return CLI_OK;
5000 }
5001
5002 /* Unhide an avp.
5003 *
5004 * This unencodes the AVP using the L2TP secret and the previously
5005 * stored random vector. It overwrites the hidden data with the
5006 * unhidden AVP subformat.
5007 */
5008 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5009 {
5010 MD5_CTX ctx;
5011 uint8_t digest[16];
5012 uint8_t *last;
5013 size_t d = 0;
5014 uint16_t m = htons(type);
5015
5016 // Compute initial pad
5017 MD5Init(&ctx);
5018 MD5Update(&ctx, (unsigned char *) &m, 2);
5019 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5020 MD5Update(&ctx, vector, vec_len);
5021 MD5Final(digest, &ctx);
5022
5023 // pointer to last decoded 16 octets
5024 last = value;
5025
5026 while (len > 0)
5027 {
5028 // calculate a new pad based on the last decoded block
5029 if (d >= sizeof(digest))
5030 {
5031 MD5Init(&ctx);
5032 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
5033 MD5Update(&ctx, last, sizeof(digest));
5034 MD5Final(digest, &ctx);
5035
5036 d = 0;
5037 last = value;
5038 }
5039
5040 *value++ ^= digest[d++];
5041 len--;
5042 }
5043 }
5044
5045 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5046 {
5047 switch (p->op)
5048 {
5049 case FILTER_PORT_OP_EQ: return port == p->port;
5050 case FILTER_PORT_OP_NEQ: return port != p->port;
5051 case FILTER_PORT_OP_GT: return port > p->port;
5052 case FILTER_PORT_OP_LT: return port < p->port;
5053 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5054 }
5055
5056 return 0;
5057 }
5058
5059 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5060 {
5061 switch (op)
5062 {
5063 case FILTER_FLAG_OP_ANY:
5064 return (flags & sflags) || (~flags & cflags);
5065
5066 case FILTER_FLAG_OP_ALL:
5067 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5068
5069 case FILTER_FLAG_OP_EST:
5070 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5071 }
5072
5073 return 0;
5074 }
5075
5076 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5077 {
5078 uint16_t frag_offset;
5079 uint8_t proto;
5080 in_addr_t src_ip;
5081 in_addr_t dst_ip;
5082 uint16_t src_port = 0;
5083 uint16_t dst_port = 0;
5084 uint8_t flags = 0;
5085 ip_filter_rulet *rule;
5086
5087 if (len < 20) // up to end of destination address
5088 return 0;
5089
5090 if ((*buf >> 4) != 4) // IPv4
5091 return 0;
5092
5093 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5094 proto = buf[9];
5095 src_ip = *(in_addr_t *) (buf + 12);
5096 dst_ip = *(in_addr_t *) (buf + 16);
5097
5098 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5099 {
5100 int l = (buf[0] & 0xf) * 4; // length of IP header
5101 if (len < l + 4) // ports
5102 return 0;
5103
5104 src_port = ntohs(*(uint16_t *) (buf + l));
5105 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5106 if (proto == IPPROTO_TCP)
5107 {
5108 if (len < l + 14) // flags
5109 return 0;
5110
5111 flags = buf[l + 13] & 0x3f;
5112 }
5113 }
5114
5115 for (rule = ip_filters[filter].rules; rule->action; rule++)
5116 {
5117 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5118 continue;
5119
5120 if (rule->src_wild != INADDR_BROADCAST &&
5121 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5122 continue;
5123
5124 if (rule->dst_wild != INADDR_BROADCAST &&
5125 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5126 continue;
5127
5128 if (frag_offset)
5129 {
5130 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5131 continue;
5132 }
5133 else
5134 {
5135 if (rule->frag)
5136 continue;
5137
5138 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5139 {
5140 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5141 continue;
5142
5143 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5144 continue;
5145
5146 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5147 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5148 continue;
5149 }
5150 }
5151
5152 // matched
5153 rule->counter++;
5154 return rule->action == FILTER_ACTION_PERMIT;
5155 }
5156
5157 // default deny
5158 return 0;
5159 }