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[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 1.135 2005-09-16 05:35:31 bodea Exp $";
8
9 #include <arpa/inet.h>
10 #include <assert.h>
11 #include <errno.h>
12 #include <fcntl.h>
13 #include <linux/if_tun.h>
14 #define SYSLOG_NAMES
15 #include <syslog.h>
16 #include <malloc.h>
17 #include <math.h>
18 #include <net/route.h>
19 #include <sys/mman.h>
20 #include <netdb.h>
21 #include <netinet/in.h>
22 #include <netinet/ip6.h>
23 #include <stdarg.h>
24 #include <stdlib.h>
25 #include <stdio.h>
26 #include <string.h>
27 #include <ctype.h>
28 #include <sys/ioctl.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/resource.h>
33 #include <sys/wait.h>
34 #include <linux/if.h>
35 #include <stddef.h>
36 #include <time.h>
37 #include <dlfcn.h>
38 #include <unistd.h>
39 #include <sched.h>
40 #include <sys/sysinfo.h>
41 #include <libcli.h>
42
43 #include "md5.h"
44 #include "l2tpns.h"
45 #include "cluster.h"
46 #include "plugin.h"
47 #include "ll.h"
48 #include "constants.h"
49 #include "control.h"
50 #include "util.h"
51 #include "tbf.h"
52
53 #ifdef BGP
54 #include "bgp.h"
55 #endif
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int daefd = -1; // Socket listening for DAE connections.
64 int snoopfd = -1; // UDP file handle for sending out intercept data
65 int *radfds = NULL; // RADIUS requests file handles
66 int ifrfd = -1; // File descriptor for routing, etc
67 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
68 int rand_fd = -1; // Random data source
69 int cluster_sockfd = -1; // Intra-cluster communications socket.
70 int epollfd = -1; // event polling
71 time_t basetime = 0; // base clock
72 char hostname[1000] = ""; // us.
73 static int tunidx; // ifr_ifindex of tun device
74 static int syslog_log = 0; // are we logging to syslog
75 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
76 uint32_t last_id = 0; // Unique ID for radius accounting
77
78 // calculated from config->l2tp_mtu
79 uint16_t MRU = 0; // PPP MRU
80 uint16_t MSS = 0; // TCP MSS
81
82 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
83 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
84
85 static void *ip_hash[256]; // Mapping from IP address to session structures.
86 struct ipv6radix {
87 int sess;
88 struct ipv6radix *branch;
89 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
90
91 // Traffic counters.
92 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
93 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
94 uint32_t eth_tx = 0;
95
96 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
97 time_t time_now = 0; // Current time in seconds since epoch.
98 static char time_now_string[64] = {0}; // Current time as a string.
99 char main_quit = 0; // True if we're in the process of exiting.
100 linked_list *loaded_plugins;
101 linked_list *plugins[MAX_PLUGIN_TYPES];
102
103 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
104 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
105
106 config_descriptt config_values[] = {
107 CONFIG("debug", debug, INT),
108 CONFIG("log_file", log_filename, STRING),
109 CONFIG("pid_file", pid_file, STRING),
110 CONFIG("random_device", random_device, STRING),
111 CONFIG("l2tp_secret", l2tp_secret, STRING),
112 CONFIG("l2tp_mtu", l2tp_mtu, INT),
113 CONFIG("ppp_restart_time", ppp_restart_time, INT),
114 CONFIG("ppp_max_configure", ppp_max_configure, INT),
115 CONFIG("ppp_max_failure", ppp_max_failure, INT),
116 CONFIG("primary_dns", default_dns1, IPv4),
117 CONFIG("secondary_dns", default_dns2, IPv4),
118 CONFIG("primary_radius", radiusserver[0], IPv4),
119 CONFIG("secondary_radius", radiusserver[1], IPv4),
120 CONFIG("primary_radius_port", radiusport[0], SHORT),
121 CONFIG("secondary_radius_port", radiusport[1], SHORT),
122 CONFIG("radius_accounting", radius_accounting, BOOL),
123 CONFIG("radius_interim", radius_interim, INT),
124 CONFIG("radius_secret", radiussecret, STRING),
125 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
126 CONFIG("radius_dae_port", radius_dae_port, SHORT),
127 CONFIG("allow_duplicate_users", allow_duplicate_users, BOOL),
128 CONFIG("bind_address", bind_address, IPv4),
129 CONFIG("peer_address", peer_address, IPv4),
130 CONFIG("send_garp", send_garp, BOOL),
131 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
132 CONFIG("throttle_buckets", num_tbfs, INT),
133 CONFIG("accounting_dir", accounting_dir, STRING),
134 CONFIG("setuid", target_uid, INT),
135 CONFIG("dump_speed", dump_speed, BOOL),
136 CONFIG("multi_read_count", multi_read_count, INT),
137 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
138 CONFIG("lock_pages", lock_pages, BOOL),
139 CONFIG("icmp_rate", icmp_rate, INT),
140 CONFIG("packet_limit", max_packets, INT),
141 CONFIG("cluster_address", cluster_address, IPv4),
142 CONFIG("cluster_interface", cluster_interface, STRING),
143 CONFIG("cluster_mcast_ttl", cluster_mcast_ttl, INT),
144 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
145 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
146 CONFIG("cluster_master_min_adv", cluster_master_min_adv, INT),
147 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
148 { NULL, 0, 0, 0 },
149 };
150
151 static char *plugin_functions[] = {
152 NULL,
153 "plugin_pre_auth",
154 "plugin_post_auth",
155 "plugin_packet_rx",
156 "plugin_packet_tx",
157 "plugin_timer",
158 "plugin_new_session",
159 "plugin_kill_session",
160 "plugin_control",
161 "plugin_radius_response",
162 "plugin_radius_reset",
163 "plugin_become_master",
164 "plugin_new_session_master",
165 };
166
167 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
168
169 // Counters for shutdown sessions
170 static sessiont shut_acct[8192];
171 static sessionidt shut_acct_n = 0;
172
173 tunnelt *tunnel = NULL; // Array of tunnel structures.
174 sessiont *session = NULL; // Array of session structures.
175 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
176 radiust *radius = NULL; // Array of radius structures.
177 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
178 ip_filtert *ip_filters = NULL; // Array of named filters.
179 static controlt *controlfree = 0;
180 struct Tstats *_statistics = NULL;
181 #ifdef RINGBUFFER
182 struct Tringbuffer *ringbuffer = NULL;
183 #endif
184
185 static void cache_ipmap(in_addr_t ip, int s);
186 static void uncache_ipmap(in_addr_t ip);
187 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
188 static void free_ip_address(sessionidt s);
189 static void dump_acct_info(int all);
190 static void sighup_handler(int sig);
191 static void sigalrm_handler(int sig);
192 static void shutdown_handler(int sig);
193 static void sigchild_handler(int sig);
194 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response);
195 static void update_config(void);
196 static void read_config_file(void);
197 static void initplugins(void);
198 static int add_plugin(char *plugin_name);
199 static int remove_plugin(char *plugin_name);
200 static void plugins_done(void);
201 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
202 static tunnelidt new_tunnel(void);
203 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
204
205 // on slaves, alow BGP to withdraw cleanly before exiting
206 #define QUIT_DELAY 5
207
208 // quit actions (master)
209 #define QUIT_FAILOVER 1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
210 #define QUIT_SHUTDOWN 2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
211
212 // return internal time (10ths since process startup), set f if given
213 static clockt now(double *f)
214 {
215 struct timeval t;
216 gettimeofday(&t, 0);
217 if (f) *f = t.tv_sec + t.tv_usec / 1000000.0;
218 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
219 }
220
221 // work out a retry time based on try number
222 // This is a straight bounded exponential backoff.
223 // Maximum re-try time is 32 seconds. (2^5).
224 clockt backoff(uint8_t try)
225 {
226 if (try > 5) try = 5; // max backoff
227 return now(NULL) + 10 * (1 << try);
228 }
229
230
231 //
232 // Log a debug message. Typically called via the LOG macro
233 //
234 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
235 {
236 static char message[65536] = {0};
237 va_list ap;
238
239 #ifdef RINGBUFFER
240 if (ringbuffer)
241 {
242 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
243 ringbuffer->tail = 0;
244 if (ringbuffer->tail == ringbuffer->head)
245 if (++ringbuffer->head >= RINGBUFFER_SIZE)
246 ringbuffer->head = 0;
247
248 ringbuffer->buffer[ringbuffer->tail].level = level;
249 ringbuffer->buffer[ringbuffer->tail].session = s;
250 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
251 va_start(ap, format);
252 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
253 va_end(ap);
254 }
255 #endif
256
257 if (config->debug < level) return;
258
259 va_start(ap, format);
260 vsnprintf(message, sizeof(message), format, ap);
261
262 if (log_stream)
263 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
264 else if (syslog_log)
265 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
266
267 va_end(ap);
268 }
269
270 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize)
271 {
272 int i, j;
273 const uint8_t *d = data;
274
275 if (config->debug < level) return;
276
277 // No support for _log_hex to syslog
278 if (log_stream)
279 {
280 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
281 setvbuf(log_stream, NULL, _IOFBF, 16384);
282
283 for (i = 0; i < maxsize; )
284 {
285 fprintf(log_stream, "%4X: ", i);
286 for (j = i; j < maxsize && j < (i + 16); j++)
287 {
288 fprintf(log_stream, "%02X ", d[j]);
289 if (j == i + 7)
290 fputs(": ", log_stream);
291 }
292
293 for (; j < i + 16; j++)
294 {
295 fputs(" ", log_stream);
296 if (j == i + 7)
297 fputs(": ", log_stream);
298 }
299
300 fputs(" ", log_stream);
301 for (j = i; j < maxsize && j < (i + 16); j++)
302 {
303 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
304 fputc(d[j], log_stream);
305 else
306 fputc('.', log_stream);
307
308 if (j == i + 7)
309 fputs(" ", log_stream);
310 }
311
312 i = j;
313 fputs("\n", log_stream);
314 }
315
316 fflush(log_stream);
317 setbuf(log_stream, NULL);
318 }
319 }
320
321 // update a counter, accumulating 2^32 wraps
322 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta)
323 {
324 uint32_t new = *counter + delta;
325 if (new < *counter)
326 (*wrap)++;
327
328 *counter = new;
329 }
330
331 // initialise the random generator
332 static void initrandom(char *source)
333 {
334 static char path[sizeof(config->random_device)] = "*undefined*";
335
336 // reinitialise only if we are forced to do so or if the config has changed
337 if (source && !strncmp(path, source, sizeof(path)))
338 return;
339
340 // close previous source, if any
341 if (rand_fd >= 0)
342 close(rand_fd);
343
344 rand_fd = -1;
345
346 if (source)
347 {
348 // register changes
349 snprintf(path, sizeof(path), "%s", source);
350
351 if (*path == '/')
352 {
353 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
354 if (rand_fd < 0)
355 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
356 path, strerror(errno));
357 }
358 }
359 }
360
361 // fill buffer with random data
362 void random_data(uint8_t *buf, int len)
363 {
364 int n = 0;
365
366 CSTAT(random_data);
367 if (rand_fd >= 0)
368 {
369 n = read(rand_fd, buf, len);
370 if (n >= len) return;
371 if (n < 0)
372 {
373 if (errno != EAGAIN)
374 {
375 LOG(0, 0, 0, "Error reading from random source: %s\n",
376 strerror(errno));
377
378 // fall back to rand()
379 initrandom(NULL);
380 }
381
382 n = 0;
383 }
384 }
385
386 // append missing data
387 while (n < len)
388 // not using the low order bits from the prng stream
389 buf[n++] = (rand() >> 4) & 0xff;
390 }
391
392 // Add a route
393 //
394 // This adds it to the routing table, advertises it
395 // via BGP if enabled, and stuffs it into the
396 // 'sessionbyip' cache.
397 //
398 // 'ip' and 'mask' must be in _host_ order.
399 //
400 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
401 {
402 struct rtentry r;
403 int i;
404
405 if (!mask) mask = 0xffffffff;
406
407 ip &= mask; // Force the ip to be the first one in the route.
408
409 memset(&r, 0, sizeof(r));
410 r.rt_dev = config->tundevice;
411 r.rt_dst.sa_family = AF_INET;
412 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
413 r.rt_gateway.sa_family = AF_INET;
414 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
415 r.rt_genmask.sa_family = AF_INET;
416 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
417 r.rt_flags = (RTF_UP | RTF_STATIC);
418 if (gw)
419 r.rt_flags |= RTF_GATEWAY;
420 else if (mask == 0xffffffff)
421 r.rt_flags |= RTF_HOST;
422
423 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
424 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
425 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
426
427 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
428 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
429
430 #ifdef BGP
431 if (add)
432 bgp_add_route(htonl(ip), htonl(mask));
433 else
434 bgp_del_route(htonl(ip), htonl(mask));
435 #endif /* BGP */
436
437 // Add/Remove the IPs to the 'sessionbyip' cache.
438 // Note that we add the zero address in the case of
439 // a network route. Roll on CIDR.
440
441 // Note that 's == 0' implies this is the address pool.
442 // We still cache it here, because it will pre-fill
443 // the malloc'ed tree.
444
445 if (s)
446 {
447 if (!add) // Are we deleting a route?
448 s = 0; // Caching the session as '0' is the same as uncaching.
449
450 for (i = ip; (i&mask) == (ip&mask) ; ++i)
451 cache_ipmap(i, s);
452 }
453 }
454
455 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
456 {
457 struct in6_rtmsg rt;
458 char ipv6addr[INET6_ADDRSTRLEN];
459
460 if (ifr6fd < 0)
461 {
462 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
463 return;
464 }
465
466 memset(&rt, 0, sizeof(rt));
467
468 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
469 rt.rtmsg_dst_len = prefixlen;
470 rt.rtmsg_metric = 1;
471 rt.rtmsg_flags = RTF_UP;
472 rt.rtmsg_ifindex = tunidx;
473
474 LOG(1, 0, 0, "Route %s %s/%d\n",
475 add ? "add" : "del",
476 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
477 prefixlen);
478
479 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
480 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
481 strerror(errno));
482
483 // FIXME: need to add BGP routing (RFC2858)
484
485 if (s)
486 {
487 if (!add) // Are we deleting a route?
488 s = 0; // Caching the session as '0' is the same as uncaching.
489
490 cache_ipv6map(ip, prefixlen, s);
491 }
492
493 return;
494 }
495
496 // defined in linux/ipv6.h, but tricky to include from user-space
497 // TODO: move routing to use netlink rather than ioctl
498 struct in6_ifreq {
499 struct in6_addr ifr6_addr;
500 __u32 ifr6_prefixlen;
501 unsigned int ifr6_ifindex;
502 };
503
504 //
505 // Set up TUN interface
506 static void inittun(void)
507 {
508 struct ifreq ifr;
509 struct in6_ifreq ifr6;
510 struct sockaddr_in sin = {0};
511 memset(&ifr, 0, sizeof(ifr));
512 ifr.ifr_flags = IFF_TUN;
513
514 tunfd = open(TUNDEVICE, O_RDWR);
515 if (tunfd < 0)
516 { // fatal
517 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
518 exit(1);
519 }
520 {
521 int flags = fcntl(tunfd, F_GETFL, 0);
522 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
523 }
524 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
525 {
526 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
527 exit(1);
528 }
529 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
530 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
531 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
532
533 sin.sin_family = AF_INET;
534 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
535 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
536
537 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
538 {
539 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
540 exit(1);
541 }
542 /* Bump up the qlen to deal with bursts from the network */
543 ifr.ifr_qlen = 1000;
544 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
545 {
546 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
547 exit(1);
548 }
549 ifr.ifr_flags = IFF_UP;
550 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
551 {
552 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
553 exit(1);
554 }
555 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
556 {
557 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
558 exit(1);
559 }
560 tunidx = ifr.ifr_ifindex;
561
562 // Only setup IPv6 on the tun device if we have a configured prefix
563 if (config->ipv6_prefix.s6_addr[0]) {
564 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
565
566 // Link local address is FE80::1
567 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
568 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
569 ifr6.ifr6_addr.s6_addr[1] = 0x80;
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 link local address:"
576 " %s\n", strerror(errno));
577 }
578
579 // Global address is prefix::1
580 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
581 ifr6.ifr6_addr = config->ipv6_prefix;
582 ifr6.ifr6_addr.s6_addr[15] = 1;
583 ifr6.ifr6_prefixlen = 64;
584 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
585 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
586 {
587 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
588 strerror(errno));
589 }
590 }
591 }
592
593 // set up UDP ports
594 static void initudp(void)
595 {
596 int on = 1;
597 struct sockaddr_in addr;
598
599 // Tunnel
600 memset(&addr, 0, sizeof(addr));
601 addr.sin_family = AF_INET;
602 addr.sin_port = htons(L2TPPORT);
603 addr.sin_addr.s_addr = config->bind_address;
604 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
605 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
606 {
607 int flags = fcntl(udpfd, F_GETFL, 0);
608 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
609 }
610 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
611 {
612 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
613 exit(1);
614 }
615
616 // Control
617 memset(&addr, 0, sizeof(addr));
618 addr.sin_family = AF_INET;
619 addr.sin_port = htons(NSCTL_PORT);
620 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
621 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
622 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
623 {
624 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
625 exit(1);
626 }
627
628 // Dynamic Authorization Extensions to RADIUS
629 memset(&addr, 0, sizeof(addr));
630 addr.sin_family = AF_INET;
631 addr.sin_port = htons(config->radius_dae_port);
632 daefd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
633 setsockopt(daefd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
634 if (bind(daefd, (void *) &addr, sizeof(addr)) < 0)
635 {
636 LOG(0, 0, 0, "Error in DAE bind: %s\n", strerror(errno));
637 exit(1);
638 }
639
640 // Intercept
641 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
642 }
643
644 //
645 // Find session by IP, < 1 for not found
646 //
647 // Confusingly enough, this 'ip' must be
648 // in _network_ order. This being the common
649 // case when looking it up from IP packet headers.
650 //
651 // We actually use this cache for two things.
652 // #1. For used IP addresses, this maps to the
653 // session ID that it's used by.
654 // #2. For un-used IP addresses, this maps to the
655 // index into the pool table that contains that
656 // IP address.
657 //
658
659 static int lookup_ipmap(in_addr_t ip)
660 {
661 uint8_t *a = (uint8_t *) &ip;
662 uint8_t **d = (uint8_t **) ip_hash;
663
664 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
665 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
666 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
667
668 return (int) (intptr_t) d[(size_t) *a];
669 }
670
671 static int lookup_ipv6map(struct in6_addr ip)
672 {
673 struct ipv6radix *curnode;
674 int i;
675 int s;
676 char ipv6addr[INET6_ADDRSTRLEN];
677
678 curnode = &ipv6_hash[ip.s6_addr[0]];
679 i = 1;
680 s = curnode->sess;
681
682 while (s == 0 && i < 15 && curnode->branch != NULL)
683 {
684 curnode = &curnode->branch[ip.s6_addr[i]];
685 s = curnode->sess;
686 i++;
687 }
688
689 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
690 inet_ntop(AF_INET6, &ip, ipv6addr,
691 INET6_ADDRSTRLEN),
692 s);
693
694 return s;
695 }
696
697 sessionidt sessionbyip(in_addr_t ip)
698 {
699 int s = lookup_ipmap(ip);
700 CSTAT(sessionbyip);
701
702 if (s > 0 && s < MAXSESSION && session[s].opened)
703 return (sessionidt) s;
704
705 return 0;
706 }
707
708 sessionidt sessionbyipv6(struct in6_addr ip)
709 {
710 int s;
711 CSTAT(sessionbyipv6);
712
713 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
714 (ip.s6_addr[0] == 0xFE &&
715 ip.s6_addr[1] == 0x80 &&
716 ip.s6_addr16[1] == 0 &&
717 ip.s6_addr16[2] == 0 &&
718 ip.s6_addr16[3] == 0)) {
719 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
720 } else {
721 s = lookup_ipv6map(ip);
722 }
723
724 if (s > 0 && s < MAXSESSION && session[s].opened)
725 return s;
726
727 return 0;
728 }
729
730 //
731 // Take an IP address in HOST byte order and
732 // add it to the sessionid by IP cache.
733 //
734 // (It's actually cached in network order)
735 //
736 static void cache_ipmap(in_addr_t ip, int s)
737 {
738 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
739 uint8_t *a = (uint8_t *) &nip;
740 uint8_t **d = (uint8_t **) ip_hash;
741 int i;
742
743 for (i = 0; i < 3; i++)
744 {
745 if (!d[(size_t) a[i]])
746 {
747 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
748 return;
749 }
750
751 d = (uint8_t **) d[(size_t) a[i]];
752 }
753
754 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
755
756 if (s > 0)
757 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
758
759 else if (s == 0)
760 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
761 // else a map to an ip pool index.
762 }
763
764 static void uncache_ipmap(in_addr_t ip)
765 {
766 cache_ipmap(ip, 0); // Assign it to the NULL session.
767 }
768
769 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
770 {
771 int i;
772 int bytes;
773 struct ipv6radix *curnode;
774 char ipv6addr[INET6_ADDRSTRLEN];
775
776 curnode = &ipv6_hash[ip.s6_addr[0]];
777
778 bytes = prefixlen >> 3;
779 i = 1;
780 while (i < bytes) {
781 if (curnode->branch == NULL)
782 {
783 if (!(curnode->branch = calloc(256,
784 sizeof (struct ipv6radix))))
785 return;
786 }
787 curnode = &curnode->branch[ip.s6_addr[i]];
788 i++;
789 }
790
791 curnode->sess = s;
792
793 if (s > 0)
794 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
795 inet_ntop(AF_INET6, &ip, ipv6addr,
796 INET6_ADDRSTRLEN),
797 prefixlen);
798 else if (s == 0)
799 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
800 inet_ntop(AF_INET6, &ip, ipv6addr,
801 INET6_ADDRSTRLEN),
802 prefixlen);
803 }
804
805 //
806 // CLI list to dump current ipcache.
807 //
808 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
809 {
810 char **d = (char **) ip_hash, **e, **f, **g;
811 int i, j, k, l;
812 int count = 0;
813
814 if (CLI_HELP_REQUESTED)
815 return CLI_HELP_NO_ARGS;
816
817 cli_print(cli, "%7s %s", "Sess#", "IP Address");
818
819 for (i = 0; i < 256; ++i)
820 {
821 if (!d[i])
822 continue;
823 e = (char **) d[i];
824 for (j = 0; j < 256; ++j)
825 {
826 if (!e[j])
827 continue;
828 f = (char **) e[j];
829 for (k = 0; k < 256; ++k)
830 {
831 if (!f[k])
832 continue;
833 g = (char **)f[k];
834 for (l = 0; l < 256; ++l)
835 {
836 if (!g[l])
837 continue;
838 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
839 ++count;
840 }
841 }
842 }
843 }
844 cli_print(cli, "%d entries in cache", count);
845 return CLI_OK;
846 }
847
848
849 // Find session by username, 0 for not found
850 // walled garden users aren't authenticated, so the username is
851 // reasonably useless. Ignore them to avoid incorrect actions
852 //
853 // This is VERY inefficent. Don't call it often. :)
854 //
855 sessionidt sessionbyuser(char *username)
856 {
857 int s;
858 CSTAT(sessionbyuser);
859
860 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
861 {
862 if (!session[s].opened)
863 continue;
864
865 if (session[s].walled_garden)
866 continue; // Skip walled garden users.
867
868 if (!strncmp(session[s].user, username, 128))
869 return s;
870
871 }
872 return 0; // Not found.
873 }
874
875 void send_garp(in_addr_t ip)
876 {
877 int s;
878 struct ifreq ifr;
879 uint8_t mac[6];
880
881 s = socket(PF_INET, SOCK_DGRAM, 0);
882 if (s < 0)
883 {
884 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
885 return;
886 }
887 memset(&ifr, 0, sizeof(ifr));
888 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
889 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
890 {
891 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
892 close(s);
893 return;
894 }
895 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
896 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
897 {
898 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
899 close(s);
900 return;
901 }
902 close(s);
903 sendarp(ifr.ifr_ifindex, mac, ip);
904 }
905
906 static sessiont *sessiontbysessionidt(sessionidt s)
907 {
908 if (!s || s >= MAXSESSION) return NULL;
909 return &session[s];
910 }
911
912 static sessionidt sessionidtbysessiont(sessiont *s)
913 {
914 sessionidt val = s-session;
915 if (s < session || val >= MAXSESSION) return 0;
916 return val;
917 }
918
919 // actually send a control message for a specific tunnel
920 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
921 {
922 struct sockaddr_in addr;
923
924 CSTAT(tunnelsend);
925
926 if (!t)
927 {
928 static int backtrace_count = 0;
929 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
930 STAT(tunnel_tx_errors);
931 log_backtrace(backtrace_count, 5)
932 return;
933 }
934
935 if (!tunnel[t].ip)
936 {
937 static int backtrace_count = 0;
938 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
939 log_backtrace(backtrace_count, 5)
940 STAT(tunnel_tx_errors);
941 return;
942 }
943
944 memset(&addr, 0, sizeof(addr));
945 addr.sin_family = AF_INET;
946 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
947 addr.sin_port = htons(tunnel[t].port);
948
949 // sequence expected, if sequence in message
950 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
951
952 // If this is a control message, deal with retries
953 if (*buf & 0x80)
954 {
955 tunnel[t].last = time_now; // control message sent
956 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
957 if (tunnel[t].try > 1)
958 {
959 STAT(tunnel_retries);
960 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
961 }
962 }
963
964 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
965 {
966 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
967 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
968 STAT(tunnel_tx_errors);
969 return;
970 }
971
972 LOG_HEX(5, "Send Tunnel Data", buf, l);
973 STAT(tunnel_tx_packets);
974 INC_STAT(tunnel_tx_bytes, l);
975 }
976
977 //
978 // Tiny helper function to write data to
979 // the 'tun' device.
980 //
981 int tun_write(uint8_t * data, int size)
982 {
983 return write(tunfd, data, size);
984 }
985
986 // adjust tcp mss to avoid fragmentation (called only for tcp packets with syn set)
987 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp)
988 {
989 int d = (tcp[12] >> 4) * 4;
990 uint8_t *mss = 0;
991 uint8_t *opts;
992 uint8_t *data;
993
994 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
995 return;
996
997 if (tcp + d > buf + len) // short?
998 return;
999
1000 opts = tcp + 20;
1001 data = tcp + d;
1002
1003 while (opts < data)
1004 {
1005 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1006 {
1007 mss = opts + 2;
1008 if (mss + 2 > data) return; // short?
1009 break;
1010 }
1011
1012 if (*opts == 0) return; // end of options
1013 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1014 opts++;
1015 else
1016 opts += opts[1]; // skip over option
1017 }
1018
1019 if (!mss) return; // not found
1020 if (ntohs(*(uint16_t *) mss) <= MSS) return; // mss OK
1021
1022 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s, adjusted mss from %u to %u\n",
1023 fmtaddr(*(in_addr_t *)(buf + 12), 0), ntohs(*(uint16_t *)tcp),
1024 fmtaddr(*(in_addr_t *)(buf + 16), 1), ntohs(*(uint16_t *)(tcp + 2)),
1025 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "",
1026 ntohs(*(uint16_t *) mss), MSS);
1027
1028 // FIXME
1029 }
1030
1031 // process outgoing (to tunnel) IP
1032 //
1033 static void processipout(uint8_t *buf, int len)
1034 {
1035 sessionidt s;
1036 sessiont *sp;
1037 tunnelidt t;
1038 in_addr_t ip;
1039
1040 uint8_t *data = buf; // Keep a copy of the originals.
1041 int size = len;
1042
1043 uint8_t b[MAXETHER + 20];
1044
1045 CSTAT(processipout);
1046
1047 if (len < MIN_IP_SIZE)
1048 {
1049 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1050 STAT(tun_rx_errors);
1051 return;
1052 }
1053 if (len >= MAXETHER)
1054 {
1055 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1056 STAT(tun_rx_errors);
1057 return;
1058 }
1059
1060 // Skip the tun header
1061 buf += 4;
1062 len -= 4;
1063
1064 // Got an IP header now
1065 if (*(uint8_t *)(buf) >> 4 != 4)
1066 {
1067 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1068 return;
1069 }
1070
1071 ip = *(uint32_t *)(buf + 16);
1072 if (!(s = sessionbyip(ip)))
1073 {
1074 // Is this a packet for a session that doesn't exist?
1075 static int rate = 0; // Number of ICMP packets we've sent this second.
1076 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1077
1078 if (last != time_now)
1079 {
1080 last = time_now;
1081 rate = 0;
1082 }
1083
1084 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1085 {
1086 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1087 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1088 config->bind_address ? config->bind_address : my_address, buf, len);
1089 }
1090 return;
1091 }
1092 t = session[s].tunnel;
1093 sp = &session[s];
1094
1095 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1096 if (config->max_packets > 0)
1097 {
1098 if (sess_local[s].last_packet_out == TIME)
1099 {
1100 int max = config->max_packets;
1101
1102 // All packets for throttled sessions are handled by the
1103 // master, so further limit by using the throttle rate.
1104 // A bit of a kludge, since throttle rate is in kbps,
1105 // but should still be generous given our average DSL
1106 // packet size is 200 bytes: a limit of 28kbps equates
1107 // to around 180 packets per second.
1108 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1109 max = sp->throttle_out;
1110
1111 if (++sess_local[s].packets_out > max)
1112 {
1113 sess_local[s].packets_dropped++;
1114 return;
1115 }
1116 }
1117 else
1118 {
1119 if (sess_local[s].packets_dropped)
1120 {
1121 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1122 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1123 sess_local[s].packets_dropped, sess_local[s].packets_out,
1124 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1125 sp->user);
1126 }
1127
1128 sess_local[s].last_packet_out = TIME;
1129 sess_local[s].packets_out = 1;
1130 sess_local[s].packets_dropped = 0;
1131 }
1132 }
1133
1134 // run access-list if any
1135 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1136 return;
1137
1138 // adjust MSS on SYN and SYN,ACK packets with options
1139 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1140 {
1141 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1142 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1143 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1144 }
1145
1146 if (sp->tbf_out)
1147 {
1148 // Are we throttling this session?
1149 if (config->cluster_iam_master)
1150 tbf_queue_packet(sp->tbf_out, data, size);
1151 else
1152 master_throttle_packet(sp->tbf_out, data, size);
1153 return;
1154 }
1155 else if (sp->walled_garden && !config->cluster_iam_master)
1156 {
1157 // We are walled-gardening this
1158 master_garden_packet(s, data, size);
1159 return;
1160 }
1161
1162 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1163
1164 // Add on L2TP header
1165 {
1166 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1167 if (!p) return;
1168 tunnelsend(b, len + (p-b), t); // send it...
1169 }
1170
1171 // Snooping this session, send it to intercept box
1172 if (sp->snoop_ip && sp->snoop_port)
1173 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1174
1175 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1176 sp->cout_delta += len;
1177 sp->pout++;
1178 udp_tx += len;
1179
1180 sess_local[s].cout += len; // To send to master..
1181 sess_local[s].pout++;
1182 }
1183
1184 // process outgoing (to tunnel) IPv6
1185 //
1186 static void processipv6out(uint8_t * buf, int len)
1187 {
1188 sessionidt s;
1189 sessiont *sp;
1190 tunnelidt t;
1191 in_addr_t ip;
1192 struct in6_addr ip6;
1193
1194 uint8_t *data = buf; // Keep a copy of the originals.
1195 int size = len;
1196
1197 uint8_t b[MAXETHER + 20];
1198
1199 CSTAT(processipv6out);
1200
1201 if (len < MIN_IP_SIZE)
1202 {
1203 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1204 STAT(tunnel_tx_errors);
1205 return;
1206 }
1207 if (len >= MAXETHER)
1208 {
1209 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1210 STAT(tunnel_tx_errors);
1211 return;
1212 }
1213
1214 // Skip the tun header
1215 buf += 4;
1216 len -= 4;
1217
1218 // Got an IP header now
1219 if (*(uint8_t *)(buf) >> 4 != 6)
1220 {
1221 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1222 return;
1223 }
1224
1225 ip6 = *(struct in6_addr *)(buf+24);
1226 s = sessionbyipv6(ip6);
1227
1228 if (s == 0)
1229 {
1230 ip = *(uint32_t *)(buf + 32);
1231 s = sessionbyip(ip);
1232 }
1233
1234 if (s == 0)
1235 {
1236 // Is this a packet for a session that doesn't exist?
1237 static int rate = 0; // Number of ICMP packets we've sent this second.
1238 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1239
1240 if (last != time_now)
1241 {
1242 last = time_now;
1243 rate = 0;
1244 }
1245
1246 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1247 {
1248 // FIXME: Should send icmp6 host unreachable
1249 }
1250 return;
1251 }
1252 t = session[s].tunnel;
1253 sp = &session[s];
1254
1255 // FIXME: add DoS prevention/filters?
1256
1257 if (sp->tbf_out)
1258 {
1259 // Are we throttling this session?
1260 if (config->cluster_iam_master)
1261 tbf_queue_packet(sp->tbf_out, data, size);
1262 else
1263 master_throttle_packet(sp->tbf_out, data, size);
1264 return;
1265 }
1266 else if (sp->walled_garden && !config->cluster_iam_master)
1267 {
1268 // We are walled-gardening this
1269 master_garden_packet(s, data, size);
1270 return;
1271 }
1272
1273 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1274
1275 // Add on L2TP header
1276 {
1277 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1278 if (!p) return;
1279 tunnelsend(b, len + (p-b), t); // send it...
1280 }
1281
1282 // Snooping this session, send it to intercept box
1283 if (sp->snoop_ip && sp->snoop_port)
1284 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1285
1286 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1287 sp->cout_delta += len;
1288 sp->pout++;
1289 udp_tx += len;
1290
1291 sess_local[s].cout += len; // To send to master..
1292 sess_local[s].pout++;
1293 }
1294
1295 //
1296 // Helper routine for the TBF filters.
1297 // Used to send queued data in to the user!
1298 //
1299 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1300 {
1301 sessiont *sp;
1302 tunnelidt t;
1303 in_addr_t ip;
1304
1305 uint8_t b[MAXETHER + 20];
1306
1307 if (len < 0 || len > MAXETHER)
1308 {
1309 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1310 return;
1311 }
1312
1313 // Skip the tun header
1314 buf += 4;
1315 len -= 4;
1316
1317 ip = *(in_addr_t *)(buf + 16);
1318
1319 if (!session[s].ip)
1320 return;
1321
1322 t = session[s].tunnel;
1323 sp = &session[s];
1324
1325 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1326
1327 // Add on L2TP header
1328 {
1329 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1330 if (!p) return;
1331 tunnelsend(b, len + (p-b), t); // send it...
1332 }
1333
1334 // Snooping this session.
1335 if (sp->snoop_ip && sp->snoop_port)
1336 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1337
1338 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1339 sp->cout_delta += len;
1340 sp->pout++;
1341 udp_tx += len;
1342
1343 sess_local[s].cout += len; // To send to master..
1344 sess_local[s].pout++;
1345 }
1346
1347 // add an AVP (16 bit)
1348 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1349 {
1350 uint16_t l = (m ? 0x8008 : 0x0008);
1351 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1352 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1353 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1354 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1355 c->length += 8;
1356 }
1357
1358 // add an AVP (32 bit)
1359 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1360 {
1361 uint16_t l = (m ? 0x800A : 0x000A);
1362 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1363 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1364 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1365 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1366 c->length += 10;
1367 }
1368
1369 // add an AVP (string)
1370 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1371 {
1372 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1373 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1374 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1375 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1376 memcpy(c->buf + c->length + 6, val, strlen(val));
1377 c->length += 6 + strlen(val);
1378 }
1379
1380 // add a binary AVP
1381 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1382 {
1383 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1384 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1385 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1386 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1387 memcpy(c->buf + c->length + 6, val, len);
1388 c->length += 6 + len;
1389 }
1390
1391 // new control connection
1392 static controlt *controlnew(uint16_t mtype)
1393 {
1394 controlt *c;
1395 if (!controlfree)
1396 c = malloc(sizeof(controlt));
1397 else
1398 {
1399 c = controlfree;
1400 controlfree = c->next;
1401 }
1402 assert(c);
1403 c->next = 0;
1404 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1405 c->length = 12;
1406 control16(c, 0, mtype, 1);
1407 return c;
1408 }
1409
1410 // send zero block if nothing is waiting
1411 // (ZLB send).
1412 static void controlnull(tunnelidt t)
1413 {
1414 uint8_t buf[12];
1415 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1416 return;
1417
1418 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1419 *(uint16_t *) (buf + 2) = htons(12); // length
1420 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1421 *(uint16_t *) (buf + 6) = htons(0); // session
1422 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1423 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1424 tunnelsend(buf, 12, t);
1425 }
1426
1427 // add a control message to a tunnel, and send if within window
1428 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1429 {
1430 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1431 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1432 *(uint16_t *) (c->buf + 6) = htons(far); // session
1433 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1434 tunnel[t].ns++; // advance sequence
1435 // link in message in to queue
1436 if (tunnel[t].controlc)
1437 tunnel[t].controle->next = c;
1438 else
1439 tunnel[t].controls = c;
1440
1441 tunnel[t].controle = c;
1442 tunnel[t].controlc++;
1443
1444 // send now if space in window
1445 if (tunnel[t].controlc <= tunnel[t].window)
1446 {
1447 tunnel[t].try = 0; // first send
1448 tunnelsend(c->buf, c->length, t);
1449 }
1450 }
1451
1452 //
1453 // Throttle or Unthrottle a session
1454 //
1455 // Throttle the data from/to through a session to no more than
1456 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1457 // user).
1458 //
1459 // If either value is -1, the current value is retained for that
1460 // direction.
1461 //
1462 void throttle_session(sessionidt s, int rate_in, int rate_out)
1463 {
1464 if (!session[s].opened)
1465 return; // No-one home.
1466
1467 if (!*session[s].user)
1468 return; // User not logged in
1469
1470 if (rate_in >= 0)
1471 {
1472 int bytes = rate_in * 1024 / 8; // kbits to bytes
1473 if (session[s].tbf_in)
1474 free_tbf(session[s].tbf_in);
1475
1476 if (rate_in > 0)
1477 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1478 else
1479 session[s].tbf_in = 0;
1480
1481 session[s].throttle_in = rate_in;
1482 }
1483
1484 if (rate_out >= 0)
1485 {
1486 int bytes = rate_out * 1024 / 8;
1487 if (session[s].tbf_out)
1488 free_tbf(session[s].tbf_out);
1489
1490 if (rate_out > 0)
1491 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1492 else
1493 session[s].tbf_out = 0;
1494
1495 session[s].throttle_out = rate_out;
1496 }
1497 }
1498
1499 // add/remove filters from session (-1 = no change)
1500 void filter_session(sessionidt s, int filter_in, int filter_out)
1501 {
1502 if (!session[s].opened)
1503 return; // No-one home.
1504
1505 if (!*session[s].user)
1506 return; // User not logged in
1507
1508 // paranoia
1509 if (filter_in > MAXFILTER) filter_in = -1;
1510 if (filter_out > MAXFILTER) filter_out = -1;
1511 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1512 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1513
1514 if (filter_in >= 0)
1515 {
1516 if (session[s].filter_in)
1517 ip_filters[session[s].filter_in - 1].used--;
1518
1519 if (filter_in > 0)
1520 ip_filters[filter_in - 1].used++;
1521
1522 session[s].filter_in = filter_in;
1523 }
1524
1525 if (filter_out >= 0)
1526 {
1527 if (session[s].filter_out)
1528 ip_filters[session[s].filter_out - 1].used--;
1529
1530 if (filter_out > 0)
1531 ip_filters[filter_out - 1].used++;
1532
1533 session[s].filter_out = filter_out;
1534 }
1535 }
1536
1537 // start tidy shutdown of session
1538 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1539 {
1540 int walled_garden = session[s].walled_garden;
1541
1542
1543 CSTAT(sessionshutdown);
1544
1545 if (!session[s].opened)
1546 {
1547 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1548 return; // not a live session
1549 }
1550
1551 if (!session[s].die)
1552 {
1553 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1554 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1555 run_plugins(PLUGIN_KILL_SESSION, &data);
1556 }
1557
1558 if (session[s].ip && !walled_garden && !session[s].die)
1559 {
1560 // RADIUS Stop message
1561 uint16_t r = radiusnew(s);
1562 if (r)
1563 {
1564 // stop, if not already trying
1565 if (radius[r].state != RADIUSSTOP)
1566 radiussend(r, RADIUSSTOP);
1567 }
1568 else
1569 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1570
1571 // Save counters to dump to accounting file
1572 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1573 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1574 }
1575
1576 if (session[s].ip)
1577 { // IP allocated, clear and unroute
1578 int r;
1579 int routed = 0;
1580 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1581 {
1582 if ((session[s].ip & session[s].route[r].mask) ==
1583 (session[s].route[r].ip & session[s].route[r].mask))
1584 routed++;
1585
1586 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1587 session[s].route[r].ip = 0;
1588 }
1589
1590 if (session[s].ip_pool_index == -1) // static ip
1591 {
1592 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1593 session[s].ip = 0;
1594 }
1595 else
1596 free_ip_address(s);
1597
1598 // unroute IPv6, if setup
1599 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1600 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1601 }
1602
1603 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1604 throttle_session(s, 0, 0);
1605
1606 if (result)
1607 { // Send CDN
1608 controlt *c = controlnew(14); // sending CDN
1609 if (error)
1610 {
1611 uint8_t buf[4];
1612 *(uint16_t *) buf = htons(result);
1613 *(uint16_t *) (buf+2) = htons(error);
1614 controlb(c, 1, buf, 4, 1);
1615 }
1616 else
1617 control16(c, 1, result, 1);
1618
1619 control16(c, 14, s, 1); // assigned session (our end)
1620 controladd(c, session[s].far, session[s].tunnel); // send the message
1621 }
1622
1623 if (!session[s].die)
1624 session[s].die = TIME + 150; // Clean up in 15 seconds
1625
1626 // update filter refcounts
1627 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1628 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1629
1630 // clear PPP state
1631 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1632 sess_local[s].lcp.restart = 0;
1633 sess_local[s].ipcp.restart = 0;
1634 sess_local[s].ipv6cp.restart = 0;
1635 sess_local[s].ccp.restart = 0;
1636
1637 cluster_send_session(s);
1638 }
1639
1640 void sendipcp(sessionidt s, tunnelidt t)
1641 {
1642 uint8_t buf[MAXETHER];
1643 uint8_t *q;
1644
1645 CSTAT(sendipcp);
1646 LOG(3, s, t, "IPCP: send ConfigReq\n");
1647
1648 if (!session[s].unique_id)
1649 {
1650 if (!++last_id) ++last_id; // skip zero
1651 session[s].unique_id = last_id;
1652 }
1653
1654 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP);
1655 if (!q) return;
1656
1657 *q = ConfigReq;
1658 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1659 *(uint16_t *) (q + 2) = htons(10); // packet length
1660 q[4] = 3; // ip address option
1661 q[5] = 6; // option length
1662 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1663 config->bind_address ? config->bind_address :
1664 my_address; // send my IP
1665
1666 tunnelsend(buf, 10 + (q - buf), t); // send it
1667 }
1668
1669 void sendipv6cp(sessionidt s, tunnelidt t)
1670 {
1671 uint8_t buf[MAXETHER];
1672 uint8_t *q;
1673
1674 CSTAT(sendipv6cp);
1675 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1676
1677 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1678 if (!q) return;
1679
1680 *q = ConfigReq;
1681 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1682 // only send one type
1683 // of request
1684 *(uint16_t *) (q + 2) = htons(14);
1685 q[4] = 1; // interface identifier option
1686 q[5] = 10; // option length
1687 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1688 *(uint32_t *) (q + 10) = 0;
1689 q[13] = 1;
1690
1691 tunnelsend(buf, 14 + (q - buf), t); // send it
1692 }
1693
1694 static void sessionclear(sessionidt s)
1695 {
1696 memset(&session[s], 0, sizeof(session[s]));
1697 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1698 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1699
1700 session[s].tunnel = T_FREE; // Mark it as free.
1701 session[s].next = sessionfree;
1702 sessionfree = s;
1703 }
1704
1705 // kill a session now
1706 void sessionkill(sessionidt s, char *reason)
1707 {
1708
1709 CSTAT(sessionkill);
1710
1711 if (!session[s].opened) // not alive
1712 return;
1713
1714 if (session[s].next)
1715 {
1716 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1717 return;
1718 }
1719
1720 session[s].die = TIME;
1721 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1722 if (sess_local[s].radius)
1723 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1724
1725 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1726 sessionclear(s);
1727 cluster_send_session(s);
1728 }
1729
1730 static void tunnelclear(tunnelidt t)
1731 {
1732 if (!t) return;
1733 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1734 tunnel[t].state = TUNNELFREE;
1735 }
1736
1737 // kill a tunnel now
1738 static void tunnelkill(tunnelidt t, char *reason)
1739 {
1740 sessionidt s;
1741 controlt *c;
1742
1743 CSTAT(tunnelkill);
1744
1745 tunnel[t].state = TUNNELDIE;
1746
1747 // free control messages
1748 while ((c = tunnel[t].controls))
1749 {
1750 controlt * n = c->next;
1751 tunnel[t].controls = n;
1752 tunnel[t].controlc--;
1753 c->next = controlfree;
1754 controlfree = c;
1755 }
1756 // kill sessions
1757 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1758 if (session[s].tunnel == t)
1759 sessionkill(s, reason);
1760
1761 // free tunnel
1762 tunnelclear(t);
1763 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1764 cli_tunnel_actions[t].action = 0;
1765 cluster_send_tunnel(t);
1766 }
1767
1768 // shut down a tunnel cleanly
1769 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1770 {
1771 sessionidt s;
1772
1773 CSTAT(tunnelshutdown);
1774
1775 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1776 {
1777 // never set up, can immediately kill
1778 tunnelkill(t, reason);
1779 return;
1780 }
1781 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1782
1783 // close session
1784 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1785 if (session[s].tunnel == t)
1786 sessionshutdown(s, reason, 0, 0);
1787
1788 tunnel[t].state = TUNNELDIE;
1789 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1790 cluster_send_tunnel(t);
1791 // TBA - should we wait for sessions to stop?
1792 if (result)
1793 {
1794 controlt *c = controlnew(4); // sending StopCCN
1795 if (error)
1796 {
1797 uint8_t buf[64];
1798 int l = 4;
1799 *(uint16_t *) buf = htons(result);
1800 *(uint16_t *) (buf+2) = htons(error);
1801 if (msg)
1802 {
1803 int m = strlen(msg);
1804 if (m + 4 > sizeof(buf))
1805 m = sizeof(buf) - 4;
1806
1807 memcpy(buf+4, msg, m);
1808 l += m;
1809 }
1810
1811 controlb(c, 1, buf, l, 1);
1812 }
1813 else
1814 control16(c, 1, result, 1);
1815
1816 control16(c, 9, t, 1); // assigned tunnel (our end)
1817 controladd(c, 0, t); // send the message
1818 }
1819 }
1820
1821 // read and process packet on tunnel (UDP)
1822 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1823 {
1824 uint8_t *chapresponse = NULL;
1825 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1826 uint8_t *p = buf + 2;
1827
1828
1829 CSTAT(processudp);
1830
1831 udp_rx += len;
1832 udp_rx_pkt++;
1833 LOG_HEX(5, "UDP Data", buf, len);
1834 STAT(tunnel_rx_packets);
1835 INC_STAT(tunnel_rx_bytes, len);
1836 if (len < 6)
1837 {
1838 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1839 STAT(tunnel_rx_errors);
1840 return;
1841 }
1842 if ((buf[1] & 0x0F) != 2)
1843 {
1844 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1845 STAT(tunnel_rx_errors);
1846 return;
1847 }
1848 if (*buf & 0x40)
1849 { // length
1850 l = ntohs(*(uint16_t *) p);
1851 p += 2;
1852 }
1853 t = ntohs(*(uint16_t *) p);
1854 p += 2;
1855 s = ntohs(*(uint16_t *) p);
1856 p += 2;
1857 if (s >= MAXSESSION)
1858 {
1859 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1860 STAT(tunnel_rx_errors);
1861 return;
1862 }
1863 if (t >= MAXTUNNEL)
1864 {
1865 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1866 STAT(tunnel_rx_errors);
1867 return;
1868 }
1869 if (*buf & 0x08)
1870 { // ns/nr
1871 ns = ntohs(*(uint16_t *) p);
1872 p += 2;
1873 nr = ntohs(*(uint16_t *) p);
1874 p += 2;
1875 }
1876 if (*buf & 0x02)
1877 { // offset
1878 uint16_t o = ntohs(*(uint16_t *) p);
1879 p += o + 2;
1880 }
1881 if ((p - buf) > l)
1882 {
1883 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1884 STAT(tunnel_rx_errors);
1885 return;
1886 }
1887 l -= (p - buf);
1888
1889 // used to time out old tunnels
1890 if (t && tunnel[t].state == TUNNELOPEN)
1891 tunnel[t].lastrec = time_now;
1892
1893 if (*buf & 0x80)
1894 { // control
1895 uint16_t message = 0xFFFF; // message type
1896 uint8_t fatal = 0;
1897 uint8_t mandatory = 0;
1898 uint16_t asession = 0; // assigned session
1899 uint32_t amagic = 0; // magic number
1900 uint8_t aflags = 0; // flags from last LCF
1901 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1902 char called[MAXTEL] = ""; // called number
1903 char calling[MAXTEL] = ""; // calling number
1904
1905 if (!config->cluster_iam_master)
1906 {
1907 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1908 return;
1909 }
1910
1911 // control messages must have bits 0x80|0x40|0x08
1912 // (type, length and sequence) set, and bits 0x02|0x01
1913 // (offset and priority) clear
1914 if ((*buf & 0xCB) != 0xC8)
1915 {
1916 LOG(1, s, t, "Bad control header %02X\n", *buf);
1917 STAT(tunnel_rx_errors);
1918 return;
1919 }
1920
1921 // check for duplicate tunnel open message
1922 if (!t && ns == 0)
1923 {
1924 int i;
1925
1926 //
1927 // Is this a duplicate of the first packet? (SCCRQ)
1928 //
1929 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1930 {
1931 if (tunnel[i].state != TUNNELOPENING ||
1932 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1933 tunnel[i].port != ntohs(addr->sin_port) )
1934 continue;
1935 t = i;
1936 LOG(3, s, t, "Duplicate SCCRQ?\n");
1937 break;
1938 }
1939 }
1940
1941 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1942 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1943
1944 // if no tunnel specified, assign one
1945 if (!t)
1946 {
1947 if (!(t = new_tunnel()))
1948 {
1949 LOG(1, 0, 0, "No more tunnels\n");
1950 STAT(tunnel_overflow);
1951 return;
1952 }
1953 tunnelclear(t);
1954 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1955 tunnel[t].port = ntohs(addr->sin_port);
1956 tunnel[t].window = 4; // default window
1957 STAT(tunnel_created);
1958 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1959 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1960 }
1961
1962 // If the 'ns' just received is not the 'nr' we're
1963 // expecting, just send an ack and drop it.
1964 //
1965 // if 'ns' is less, then we got a retransmitted packet.
1966 // if 'ns' is greater than missed a packet. Either way
1967 // we should ignore it.
1968 if (ns != tunnel[t].nr)
1969 {
1970 // is this the sequence we were expecting?
1971 STAT(tunnel_rx_errors);
1972 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1973 t, ns, tunnel[t].nr);
1974
1975 if (l) // Is this not a ZLB?
1976 controlnull(t);
1977 return;
1978 }
1979
1980 // check sequence of this message
1981 {
1982 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1983 // some to clear maybe?
1984 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1985 {
1986 controlt *c = tunnel[t].controls;
1987 tunnel[t].controls = c->next;
1988 tunnel[t].controlc--;
1989 c->next = controlfree;
1990 controlfree = c;
1991 skip--;
1992 tunnel[t].try = 0; // we have progress
1993 }
1994
1995 // receiver advance (do here so quoted correctly in any sends below)
1996 if (l) tunnel[t].nr = (ns + 1);
1997 if (skip < 0) skip = 0;
1998 if (skip < tunnel[t].controlc)
1999 {
2000 // some control packets can now be sent that were previous stuck out of window
2001 int tosend = tunnel[t].window - skip;
2002 controlt *c = tunnel[t].controls;
2003 while (c && skip)
2004 {
2005 c = c->next;
2006 skip--;
2007 }
2008 while (c && tosend)
2009 {
2010 tunnel[t].try = 0; // first send
2011 tunnelsend(c->buf, c->length, t);
2012 c = c->next;
2013 tosend--;
2014 }
2015 }
2016 if (!tunnel[t].controlc)
2017 tunnel[t].retry = 0; // caught up
2018 }
2019 if (l)
2020 { // if not a null message
2021 int result = 0;
2022 int error = 0;
2023 char *msg = 0;
2024
2025 // process AVPs
2026 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2027 {
2028 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2029 uint8_t *b = p;
2030 uint8_t flags = *p;
2031 uint16_t mtype;
2032 if (n > l)
2033 {
2034 LOG(1, s, t, "Invalid length in AVP\n");
2035 STAT(tunnel_rx_errors);
2036 return;
2037 }
2038 p += n; // next
2039 l -= n;
2040 if (flags & 0x3C) // reserved bits, should be clear
2041 {
2042 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2043 fatal = flags;
2044 result = 2; // general error
2045 error = 3; // reserved field non-zero
2046 msg = 0;
2047 continue; // next
2048 }
2049 b += 2;
2050 if (*(uint16_t *) (b))
2051 {
2052 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
2053 fatal = flags;
2054 result = 2; // general error
2055 error = 6; // generic vendor-specific error
2056 msg = "unsupported vendor-specific";
2057 continue; // next
2058 }
2059 b += 2;
2060 mtype = ntohs(*(uint16_t *) (b));
2061 b += 2;
2062 n -= 6;
2063
2064 if (flags & 0x40)
2065 {
2066 uint16_t orig_len;
2067
2068 // handle hidden AVPs
2069 if (!*config->l2tp_secret)
2070 {
2071 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2072 fatal = flags;
2073 result = 2; // general error
2074 error = 6; // generic vendor-specific error
2075 msg = "secret not specified";
2076 continue;
2077 }
2078 if (!session[s].random_vector_length)
2079 {
2080 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2081 fatal = flags;
2082 result = 2; // general error
2083 error = 6; // generic
2084 msg = "no random vector";
2085 continue;
2086 }
2087 if (n < 8)
2088 {
2089 LOG(2, s, t, "Short hidden AVP.\n");
2090 fatal = flags;
2091 result = 2; // general error
2092 error = 2; // length is wrong
2093 msg = 0;
2094 continue;
2095 }
2096
2097 // Unhide the AVP
2098 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2099
2100 orig_len = ntohs(*(uint16_t *) b);
2101 if (orig_len > n + 2)
2102 {
2103 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2104 orig_len, n);
2105
2106 fatal = flags;
2107 result = 2; // general error
2108 error = 2; // length is wrong
2109 msg = 0;
2110 continue;
2111 }
2112
2113 b += 2;
2114 n = orig_len;
2115 }
2116
2117 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2118 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2119
2120 switch (mtype)
2121 {
2122 case 0: // message type
2123 message = ntohs(*(uint16_t *) b);
2124 mandatory = flags & 0x80;
2125 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2126 break;
2127 case 1: // result code
2128 {
2129 uint16_t rescode = ntohs(*(uint16_t *) b);
2130 const char* resdesc = "(unknown)";
2131 if (message == 4)
2132 { /* StopCCN */
2133 resdesc = l2tp_stopccn_result_code(rescode);
2134 }
2135 else if (message == 14)
2136 { /* CDN */
2137 resdesc = l2tp_cdn_result_code(rescode);
2138 }
2139
2140 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2141 if (n >= 4)
2142 {
2143 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2144 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2145 }
2146 if (n > 4)
2147 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2148
2149 break;
2150 }
2151 break;
2152 case 2: // protocol version
2153 {
2154 version = ntohs(*(uint16_t *) (b));
2155 LOG(4, s, t, " Protocol version = %d\n", version);
2156 if (version && version != 0x0100)
2157 { // allow 0.0 and 1.0
2158 LOG(1, s, t, " Bad protocol version %04X\n", version);
2159 fatal = flags;
2160 result = 5; // unspported protocol version
2161 error = 0x0100; // supported version
2162 msg = 0;
2163 continue; // next
2164 }
2165 }
2166 break;
2167 case 3: // framing capabilities
2168 // LOG(4, s, t, "Framing capabilities\n");
2169 break;
2170 case 4: // bearer capabilities
2171 // LOG(4, s, t, "Bearer capabilities\n");
2172 break;
2173 case 5: // tie breaker
2174 // We never open tunnels, so we don't care about tie breakers
2175 // LOG(4, s, t, "Tie breaker\n");
2176 continue;
2177 case 6: // firmware revision
2178 // LOG(4, s, t, "Firmware revision\n");
2179 break;
2180 case 7: // host name
2181 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2182 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2183 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2184 // TBA - to send to RADIUS
2185 break;
2186 case 8: // vendor name
2187 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2188 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2189 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2190 break;
2191 case 9: // assigned tunnel
2192 tunnel[t].far = ntohs(*(uint16_t *) (b));
2193 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2194 break;
2195 case 10: // rx window
2196 tunnel[t].window = ntohs(*(uint16_t *) (b));
2197 if (!tunnel[t].window)
2198 tunnel[t].window = 1; // window of 0 is silly
2199 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2200 break;
2201 case 11: // Challenge
2202 {
2203 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2204 build_chap_response(b, 2, n, &chapresponse);
2205 }
2206 break;
2207 case 13: // Response
2208 // Why did they send a response? We never challenge.
2209 LOG(2, s, t, " received unexpected challenge response\n");
2210 break;
2211
2212 case 14: // assigned session
2213 asession = session[s].far = ntohs(*(uint16_t *) (b));
2214 LOG(4, s, t, " assigned session = %d\n", asession);
2215 break;
2216 case 15: // call serial number
2217 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2218 break;
2219 case 18: // bearer type
2220 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2221 // TBA - for RADIUS
2222 break;
2223 case 19: // framing type
2224 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2225 // TBA
2226 break;
2227 case 21: // called number
2228 memset(called, 0, sizeof(called));
2229 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2230 LOG(4, s, t, " Called <%s>\n", called);
2231 break;
2232 case 22: // calling number
2233 memset(calling, 0, sizeof(calling));
2234 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2235 LOG(4, s, t, " Calling <%s>\n", calling);
2236 break;
2237 case 23: // subtype
2238 break;
2239 case 24: // tx connect speed
2240 if (n == 4)
2241 {
2242 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2243 }
2244 else
2245 {
2246 // AS5300s send connect speed as a string
2247 char tmp[30];
2248 memset(tmp, 0, sizeof(tmp));
2249 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2250 session[s].tx_connect_speed = atol(tmp);
2251 }
2252 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2253 break;
2254 case 38: // rx connect speed
2255 if (n == 4)
2256 {
2257 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2258 }
2259 else
2260 {
2261 // AS5300s send connect speed as a string
2262 char tmp[30];
2263 memset(tmp, 0, sizeof(tmp));
2264 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2265 session[s].rx_connect_speed = atol(tmp);
2266 }
2267 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2268 break;
2269 case 25: // Physical Channel ID
2270 {
2271 uint32_t tmp = ntohl(*(uint32_t *) b);
2272 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2273 break;
2274 }
2275 case 29: // Proxy Authentication Type
2276 {
2277 uint16_t atype = ntohs(*(uint16_t *)b);
2278 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2279 break;
2280 }
2281 case 30: // Proxy Authentication Name
2282 {
2283 char authname[64];
2284 memset(authname, 0, sizeof(authname));
2285 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2286 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2287 authname);
2288 break;
2289 }
2290 case 31: // Proxy Authentication Challenge
2291 {
2292 LOG(4, s, t, " Proxy Auth Challenge\n");
2293 break;
2294 }
2295 case 32: // Proxy Authentication ID
2296 {
2297 uint16_t authid = ntohs(*(uint16_t *)(b));
2298 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2299 break;
2300 }
2301 case 33: // Proxy Authentication Response
2302 LOG(4, s, t, " Proxy Auth Response\n");
2303 break;
2304 case 27: // last sent lcp
2305 { // find magic number
2306 uint8_t *p = b, *e = p + n;
2307 while (p + 1 < e && p[1] && p + p[1] <= e)
2308 {
2309 if (*p == 5 && p[1] == 6) // Magic-Number
2310 amagic = ntohl(*(uint32_t *) (p + 2));
2311 else if (*p == 7) // Protocol-Field-Compression
2312 aflags |= SESSIONPFC;
2313 else if (*p == 8) // Address-and-Control-Field-Compression
2314 aflags |= SESSIONACFC;
2315 p += p[1];
2316 }
2317 }
2318 break;
2319 case 28: // last recv lcp confreq
2320 break;
2321 case 26: // Initial Received LCP CONFREQ
2322 break;
2323 case 39: // seq required - we control it as an LNS anyway...
2324 break;
2325 case 36: // Random Vector
2326 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2327 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2328 if (n > sizeof(session[s].random_vector))
2329 n = sizeof(session[s].random_vector);
2330 memcpy(session[s].random_vector, b, n);
2331 session[s].random_vector_length = n;
2332 break;
2333 default:
2334 {
2335 static char e[] = "unknown AVP 0xXXXX";
2336 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2337 fatal = flags;
2338 result = 2; // general error
2339 error = 8; // unknown mandatory AVP
2340 sprintf((msg = e) + 14, "%04x", mtype);
2341 continue; // next
2342 }
2343 }
2344 }
2345 // process message
2346 if (fatal & 0x80)
2347 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2348 else
2349 switch (message)
2350 {
2351 case 1: // SCCRQ - Start Control Connection Request
2352 tunnel[t].state = TUNNELOPENING;
2353 if (main_quit != QUIT_SHUTDOWN)
2354 {
2355 controlt *c = controlnew(2); // sending SCCRP
2356 control16(c, 2, version, 1); // protocol version
2357 control32(c, 3, 3, 1); // framing
2358 controls(c, 7, hostname, 1); // host name
2359 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2360 control16(c, 9, t, 1); // assigned tunnel
2361 controladd(c, 0, t); // send the resply
2362 }
2363 else
2364 {
2365 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2366 }
2367 break;
2368 case 2: // SCCRP
2369 tunnel[t].state = TUNNELOPEN;
2370 break;
2371 case 3: // SCCN
2372 tunnel[t].state = TUNNELOPEN;
2373 controlnull(t); // ack
2374 break;
2375 case 4: // StopCCN
2376 controlnull(t); // ack
2377 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2378 break;
2379 case 6: // HELLO
2380 controlnull(t); // simply ACK
2381 break;
2382 case 7: // OCRQ
2383 // TBA
2384 break;
2385 case 8: // OCRO
2386 // TBA
2387 break;
2388 case 9: // OCCN
2389 // TBA
2390 break;
2391 case 10: // ICRQ
2392 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2393 {
2394 controlt *c = controlnew(11); // ICRP
2395
2396 s = sessionfree;
2397 sessionfree = session[s].next;
2398 memset(&session[s], 0, sizeof(session[s]));
2399
2400 if (s > config->cluster_highest_sessionid)
2401 config->cluster_highest_sessionid = s;
2402
2403 session[s].opened = time_now;
2404 session[s].tunnel = t;
2405 session[s].far = asession;
2406 session[s].last_packet = time_now;
2407 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2408 control16(c, 14, s, 1); // assigned session
2409 controladd(c, asession, t); // send the reply
2410
2411 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2412 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2413
2414 session[s].ppp.phase = Establish;
2415 session[s].ppp.lcp = Starting;
2416
2417 STAT(session_created);
2418 break;
2419 }
2420
2421 {
2422 controlt *c = controlnew(14); // CDN
2423 if (!sessionfree)
2424 {
2425 STAT(session_overflow);
2426 LOG(1, 0, t, "No free sessions\n");
2427 control16(c, 1, 4, 0); // temporary lack of resources
2428 }
2429 else
2430 control16(c, 1, 2, 7); // shutting down, try another
2431
2432 controladd(c, asession, t); // send the message
2433 }
2434 return;
2435 case 11: // ICRP
2436 // TBA
2437 break;
2438 case 12: // ICCN
2439 if (amagic == 0) amagic = time_now;
2440 session[s].magic = amagic; // set magic number
2441 session[s].l2tp_flags = aflags; // set flags received
2442 session[s].mru = PPPMTU; // default
2443 controlnull(t); // ack
2444
2445 // start LCP
2446 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2447 sess_local[s].lcp.conf_sent = 1;
2448 sess_local[s].lcp.nak_sent = 0;
2449 sess_local[s].lcp_authtype = config->radius_authprefer;
2450 sess_local[s].ppp_mru = MRU;
2451 session[s].ppp.lcp = RequestSent;
2452 sendlcp(s, t);
2453
2454 break;
2455 case 14: // CDN
2456 controlnull(t); // ack
2457 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2458 break;
2459 case 0xFFFF:
2460 LOG(1, s, t, "Missing message type\n");
2461 break;
2462 default:
2463 STAT(tunnel_rx_errors);
2464 if (mandatory)
2465 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2466 else
2467 LOG(1, s, t, "Unknown message type %d\n", message);
2468 break;
2469 }
2470 if (chapresponse) free(chapresponse);
2471 cluster_send_tunnel(t);
2472 }
2473 else
2474 {
2475 LOG(4, s, t, " Got a ZLB ack\n");
2476 }
2477 }
2478 else
2479 { // data
2480 uint16_t proto;
2481
2482 LOG_HEX(5, "Receive Tunnel Data", p, l);
2483 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2484 { // HDLC address header, discard
2485 p += 2;
2486 l -= 2;
2487 }
2488 if (l < 2)
2489 {
2490 LOG(1, s, t, "Short ppp length %d\n", l);
2491 STAT(tunnel_rx_errors);
2492 return;
2493 }
2494 if (*p & 1)
2495 {
2496 proto = *p++;
2497 l--;
2498 }
2499 else
2500 {
2501 proto = ntohs(*(uint16_t *) p);
2502 p += 2;
2503 l -= 2;
2504 }
2505
2506 if (s && !session[s].opened) // Is something wrong??
2507 {
2508 if (!config->cluster_iam_master)
2509 {
2510 // Pass it off to the master to deal with..
2511 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2512 return;
2513 }
2514
2515
2516 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2517 STAT(tunnel_rx_errors);
2518 return;
2519 }
2520
2521 if (proto == PPPPAP)
2522 {
2523 session[s].last_packet = time_now;
2524 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2525 processpap(s, t, p, l);
2526 }
2527 else if (proto == PPPCHAP)
2528 {
2529 session[s].last_packet = time_now;
2530 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2531 processchap(s, t, p, l);
2532 }
2533 else if (proto == PPPLCP)
2534 {
2535 session[s].last_packet = time_now;
2536 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2537 processlcp(s, t, p, l);
2538 }
2539 else if (proto == PPPIPCP)
2540 {
2541 session[s].last_packet = time_now;
2542 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2543 processipcp(s, t, p, l);
2544 }
2545 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2546 {
2547 session[s].last_packet = time_now;
2548 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2549 processipv6cp(s, t, p, l);
2550 }
2551 else if (proto == PPPCCP)
2552 {
2553 session[s].last_packet = time_now;
2554 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2555 processccp(s, t, p, l);
2556 }
2557 else if (proto == PPPIP)
2558 {
2559 if (session[s].die)
2560 {
2561 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2562 return; // closing session, PPP not processed
2563 }
2564
2565 session[s].last_packet = time_now;
2566 if (session[s].walled_garden && !config->cluster_iam_master)
2567 {
2568 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2569 return;
2570 }
2571
2572 processipin(s, t, p, l);
2573 }
2574 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2575 {
2576 if (session[s].die)
2577 {
2578 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2579 return; // closing session, PPP not processed
2580 }
2581
2582 session[s].last_packet = time_now;
2583 if (session[s].walled_garden && !config->cluster_iam_master)
2584 {
2585 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2586 return;
2587 }
2588
2589 processipv6in(s, t, p, l);
2590 }
2591 else if (session[s].ppp.lcp == Opened)
2592 {
2593 uint8_t buf[MAXETHER];
2594 uint8_t *q;
2595 int mru = session[s].mru;
2596 if (mru > sizeof(buf)) mru = sizeof(buf);
2597
2598 l += 6;
2599 if (l > mru) l = mru;
2600
2601 q = makeppp(buf, sizeof(buf), 0, 0, s, t, proto);
2602 if (!q) return;
2603
2604 *q = CodeRej;
2605 *(q + 1) = ++sess_local[s].lcp_ident;
2606 *(uint16_t *)(q + 2) = l;
2607 *(uint16_t *)(q + 4) = htons(proto);
2608 memcpy(q + 6, p, l - 6);
2609
2610 if (proto == PPPIPV6CP)
2611 LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n");
2612 else
2613 LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto);
2614
2615 tunnelsend(buf, l + (q - buf), t);
2616 }
2617 else
2618 {
2619 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2620 proto, ppp_state(session[s].ppp.lcp));
2621 }
2622 }
2623 }
2624
2625 // read and process packet on tun
2626 static void processtun(uint8_t * buf, int len)
2627 {
2628 LOG_HEX(5, "Receive TUN Data", buf, len);
2629 STAT(tun_rx_packets);
2630 INC_STAT(tun_rx_bytes, len);
2631
2632 CSTAT(processtun);
2633
2634 eth_rx_pkt++;
2635 eth_rx += len;
2636 if (len < 22)
2637 {
2638 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2639 STAT(tun_rx_errors);
2640 return;
2641 }
2642
2643 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2644 processipout(buf, len);
2645 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2646 && config->ipv6_prefix.s6_addr[0])
2647 processipv6out(buf, len);
2648
2649 // Else discard.
2650 }
2651
2652 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2653 // that we look at the whole of the tunnel, radius and session tables
2654 // every second
2655 static void regular_cleanups(double period)
2656 {
2657 // Next tunnel, radius and session to check for actions on.
2658 static tunnelidt t = 0;
2659 static int r = 0;
2660 static sessionidt s = 0;
2661
2662 int t_actions = 0;
2663 int r_actions = 0;
2664 int s_actions = 0;
2665
2666 int t_slice;
2667 int r_slice;
2668 int s_slice;
2669
2670 int i;
2671 int a;
2672
2673 // divide up tables into slices based on the last run
2674 t_slice = config->cluster_highest_tunnelid * period;
2675 r_slice = (MAXRADIUS - 1) * period;
2676 s_slice = config->cluster_highest_sessionid * period;
2677
2678 if (t_slice < 1)
2679 t_slice = 1;
2680 else if (t_slice > config->cluster_highest_tunnelid)
2681 t_slice = config->cluster_highest_tunnelid;
2682
2683 if (r_slice < 1)
2684 r_slice = 1;
2685 else if (r_slice > (MAXRADIUS - 1))
2686 r_slice = MAXRADIUS - 1;
2687
2688 if (s_slice < 1)
2689 s_slice = 1;
2690 else if (s_slice > config->cluster_highest_sessionid)
2691 s_slice = config->cluster_highest_sessionid;
2692
2693 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2694
2695 for (i = 0; i < t_slice; i++)
2696 {
2697 t++;
2698 if (t > config->cluster_highest_tunnelid)
2699 t = 1;
2700
2701 // check for expired tunnels
2702 if (tunnel[t].die && tunnel[t].die <= TIME)
2703 {
2704 STAT(tunnel_timeout);
2705 tunnelkill(t, "Expired");
2706 t_actions++;
2707 continue;
2708 }
2709 // check for message resend
2710 if (tunnel[t].retry && tunnel[t].controlc)
2711 {
2712 // resend pending messages as timeout on reply
2713 if (tunnel[t].retry <= TIME)
2714 {
2715 controlt *c = tunnel[t].controls;
2716 uint8_t w = tunnel[t].window;
2717 tunnel[t].try++; // another try
2718 if (tunnel[t].try > 5)
2719 tunnelkill(t, "Timeout on control message"); // game over
2720 else
2721 while (c && w--)
2722 {
2723 tunnelsend(c->buf, c->length, t);
2724 c = c->next;
2725 }
2726
2727 t_actions++;
2728 }
2729 }
2730 // Send hello
2731 if (tunnel[t].state == TUNNELOPEN && (time_now - tunnel[t].lastrec) > 60)
2732 {
2733 controlt *c = controlnew(6); // sending HELLO
2734 controladd(c, 0, t); // send the message
2735 LOG(3, 0, t, "Sending HELLO message\n");
2736 t_actions++;
2737 }
2738
2739 // Check for tunnel changes requested from the CLI
2740 if ((a = cli_tunnel_actions[t].action))
2741 {
2742 cli_tunnel_actions[t].action = 0;
2743 if (a & CLI_TUN_KILL)
2744 {
2745 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2746 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2747 t_actions++;
2748 }
2749 }
2750 }
2751
2752 for (i = 0; i < r_slice; i++)
2753 {
2754 r++;
2755 if (r >= MAXRADIUS)
2756 r = 1;
2757
2758 if (!radius[r].state)
2759 continue;
2760
2761 if (radius[r].retry <= TIME)
2762 {
2763 radiusretry(r);
2764 r_actions++;
2765 }
2766 }
2767
2768 for (i = 0; i < s_slice; i++)
2769 {
2770 s++;
2771 if (s > config->cluster_highest_sessionid)
2772 s = 1;
2773
2774 if (!session[s].opened) // Session isn't in use
2775 continue;
2776
2777 // check for expired sessions
2778 if (session[s].die)
2779 {
2780 if (session[s].die <= TIME)
2781 {
2782 sessionkill(s, "Expired");
2783 s_actions++;
2784 }
2785 continue;
2786 }
2787
2788 // PPP timeouts
2789 if (sess_local[s].lcp.restart <= time_now)
2790 {
2791 int next_state = session[s].ppp.lcp;
2792 switch (session[s].ppp.lcp)
2793 {
2794 case RequestSent:
2795 case AckReceived:
2796 next_state = RequestSent;
2797
2798 case AckSent:
2799 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2800 {
2801 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2802 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2803 sess_local[s].lcp.conf_sent++;
2804 sendlcp(s, session[s].tunnel);
2805 change_state(s, lcp, next_state);
2806 }
2807 else
2808 {
2809 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2810 STAT(session_timeout);
2811 }
2812
2813 s_actions++;
2814 }
2815
2816 if (session[s].die)
2817 continue;
2818 }
2819
2820 if (sess_local[s].ipcp.restart <= time_now)
2821 {
2822 int next_state = session[s].ppp.ipcp;
2823 switch (session[s].ppp.ipcp)
2824 {
2825 case RequestSent:
2826 case AckReceived:
2827 next_state = RequestSent;
2828
2829 case AckSent:
2830 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2831 {
2832 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2833 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2834 sess_local[s].ipcp.conf_sent++;
2835 sendipcp(s, session[s].tunnel);
2836 change_state(s, ipcp, next_state);
2837 }
2838 else
2839 {
2840 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2841 STAT(session_timeout);
2842 }
2843
2844 s_actions++;
2845 }
2846
2847 if (session[s].die)
2848 continue;
2849 }
2850
2851 if (sess_local[s].ipv6cp.restart <= time_now)
2852 {
2853 int next_state = session[s].ppp.ipv6cp;
2854 switch (session[s].ppp.ipv6cp)
2855 {
2856 case RequestSent:
2857 case AckReceived:
2858 next_state = RequestSent;
2859
2860 case AckSent:
2861 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2862 {
2863 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2864 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2865 sess_local[s].ipv6cp.conf_sent++;
2866 sendipv6cp(s, session[s].tunnel);
2867 change_state(s, ipv6cp, next_state);
2868 }
2869 else
2870 {
2871 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2872 change_state(s, ipv6cp, Stopped);
2873 }
2874
2875 s_actions++;
2876 }
2877 }
2878
2879 if (sess_local[s].ccp.restart <= time_now)
2880 {
2881 int next_state = session[s].ppp.ccp;
2882 switch (session[s].ppp.ccp)
2883 {
2884 case RequestSent:
2885 case AckReceived:
2886 next_state = RequestSent;
2887
2888 case AckSent:
2889 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2890 {
2891 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2892 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2893 sess_local[s].ccp.conf_sent++;
2894 sendccp(s, session[s].tunnel);
2895 change_state(s, ccp, next_state);
2896 }
2897 else
2898 {
2899 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2900 change_state(s, ccp, Stopped);
2901 }
2902
2903 s_actions++;
2904 }
2905 }
2906
2907 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2908 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2909 {
2910 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2911 STAT(session_timeout);
2912 s_actions++;
2913 continue;
2914 }
2915
2916 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2917 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2918 {
2919 uint8_t b[MAXETHER];
2920
2921 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2922 if (!q) continue;
2923
2924 *q = EchoReq;
2925 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2926 *(uint16_t *)(q + 2) = htons(8); // Length
2927 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2928
2929 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2930 (int)(time_now - session[s].last_packet));
2931 tunnelsend(b, 24, session[s].tunnel); // send it
2932 s_actions++;
2933 }
2934
2935 // Check for actions requested from the CLI
2936 if ((a = cli_session_actions[s].action))
2937 {
2938 int send = 0;
2939
2940 cli_session_actions[s].action = 0;
2941 if (a & CLI_SESS_KILL)
2942 {
2943 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2944 sessionshutdown(s, "Requested by administrator.", 3, 0);
2945 a = 0; // dead, no need to check for other actions
2946 s_actions++;
2947 }
2948
2949 if (a & CLI_SESS_NOSNOOP)
2950 {
2951 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2952 session[s].snoop_ip = 0;
2953 session[s].snoop_port = 0;
2954 s_actions++;
2955 send++;
2956 }
2957 else if (a & CLI_SESS_SNOOP)
2958 {
2959 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2960 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2961 cli_session_actions[s].snoop_port);
2962
2963 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2964 session[s].snoop_port = cli_session_actions[s].snoop_port;
2965 s_actions++;
2966 send++;
2967 }
2968
2969 if (a & CLI_SESS_NOTHROTTLE)
2970 {
2971 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2972 throttle_session(s, 0, 0);
2973 s_actions++;
2974 send++;
2975 }
2976 else if (a & CLI_SESS_THROTTLE)
2977 {
2978 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2979 cli_session_actions[s].throttle_in,
2980 cli_session_actions[s].throttle_out);
2981
2982 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2983 s_actions++;
2984 send++;
2985 }
2986
2987 if (a & CLI_SESS_NOFILTER)
2988 {
2989 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2990 filter_session(s, 0, 0);
2991 s_actions++;
2992 send++;
2993 }
2994 else if (a & CLI_SESS_FILTER)
2995 {
2996 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2997 cli_session_actions[s].filter_in,
2998 cli_session_actions[s].filter_out);
2999
3000 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3001 s_actions++;
3002 send++;
3003 }
3004
3005 if (send)
3006 cluster_send_session(s);
3007 }
3008
3009 // RADIUS interim accounting
3010 if (config->radius_accounting && config->radius_interim > 0
3011 && session[s].ip && !session[s].walled_garden
3012 && !sess_local[s].radius // RADIUS already in progress
3013 && time_now - sess_local[s].last_interim >= config->radius_interim)
3014 {
3015 int rad = radiusnew(s);
3016 if (!rad)
3017 {
3018 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3019 STAT(radius_overflow);
3020 continue;
3021 }
3022
3023 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3024 session[s].user, session[s].unique_id);
3025
3026 radiussend(rad, RADIUSINTERIM);
3027 sess_local[s].last_interim = time_now;
3028 s_actions++;
3029 }
3030 }
3031
3032 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3033 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3034 }
3035
3036 //
3037 // Are we in the middle of a tunnel update, or radius
3038 // requests??
3039 //
3040 static int still_busy(void)
3041 {
3042 int i;
3043 static clockt last_talked = 0;
3044 static clockt start_busy_wait = 0;
3045
3046 if (!config->cluster_iam_master)
3047 {
3048 #ifdef BGP
3049 static time_t stopped_bgp = 0;
3050 if (bgp_configured)
3051 {
3052 if (!stopped_bgp)
3053 {
3054 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3055
3056 for (i = 0; i < BGP_NUM_PEERS; i++)
3057 if (bgp_peers[i].state == Established)
3058 bgp_stop(&bgp_peers[i]);
3059
3060 stopped_bgp = time_now;
3061
3062 // we don't want to become master
3063 cluster_send_ping(0);
3064
3065 return 1;
3066 }
3067
3068 if (time_now < (stopped_bgp + QUIT_DELAY))
3069 return 1;
3070 }
3071 #endif /* BGP */
3072
3073 return 0;
3074 }
3075
3076 if (main_quit == QUIT_SHUTDOWN)
3077 {
3078 static int dropped = 0;
3079 if (!dropped)
3080 {
3081 int i;
3082
3083 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3084 for (i = 1; i < MAXTUNNEL; i++)
3085 if (tunnel[i].ip || tunnel[i].state)
3086 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3087
3088 dropped = 1;
3089 }
3090 }
3091
3092 if (start_busy_wait == 0)
3093 start_busy_wait = TIME;
3094
3095 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3096 {
3097 if (!tunnel[i].controlc)
3098 continue;
3099
3100 if (last_talked != TIME)
3101 {
3102 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3103 last_talked = TIME;
3104 }
3105 return 1;
3106 }
3107
3108 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3109 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3110 {
3111 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3112 return 0;
3113 }
3114
3115 for (i = 1; i < MAXRADIUS; i++)
3116 {
3117 if (radius[i].state == RADIUSNULL)
3118 continue;
3119 if (radius[i].state == RADIUSWAIT)
3120 continue;
3121
3122 if (last_talked != TIME)
3123 {
3124 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3125 last_talked = TIME;
3126 }
3127 return 1;
3128 }
3129
3130 return 0;
3131 }
3132
3133 #ifdef HAVE_EPOLL
3134 # include <sys/epoll.h>
3135 #else
3136 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3137 # include "fake_epoll.h"
3138 #endif
3139
3140 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3141 #define BASE_FDS 6
3142
3143 // additional polled fds
3144 #ifdef BGP
3145 # define EXTRA_FDS BGP_NUM_PEERS
3146 #else
3147 # define EXTRA_FDS 0
3148 #endif
3149
3150 // main loop - gets packets on tun or udp and processes them
3151 static void mainloop(void)
3152 {
3153 int i;
3154 uint8_t buf[65536];
3155 clockt next_cluster_ping = 0; // send initial ping immediately
3156 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3157 int maxevent = sizeof(events)/sizeof(*events);
3158
3159 if ((epollfd = epoll_create(maxevent)) < 0)
3160 {
3161 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3162 exit(1);
3163 }
3164
3165 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3166 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3167
3168 /* setup our fds to poll for input */
3169 {
3170 static struct event_data d[BASE_FDS];
3171 struct epoll_event e;
3172
3173 e.events = EPOLLIN;
3174 i = 0;
3175
3176 d[i].type = FD_TYPE_CLI;
3177 e.data.ptr = &d[i++];
3178 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3179
3180 d[i].type = FD_TYPE_CLUSTER;
3181 e.data.ptr = &d[i++];
3182 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3183
3184 d[i].type = FD_TYPE_TUN;
3185 e.data.ptr = &d[i++];
3186 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3187
3188 d[i].type = FD_TYPE_UDP;
3189 e.data.ptr = &d[i++];
3190 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3191
3192 d[i].type = FD_TYPE_CONTROL;
3193 e.data.ptr = &d[i++];
3194 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3195
3196 d[i].type = FD_TYPE_DAE;
3197 e.data.ptr = &d[i++];
3198 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3199 }
3200
3201 #ifdef BGP
3202 signal(SIGPIPE, SIG_IGN);
3203 bgp_setup(config->as_number);
3204 if (config->bind_address)
3205 bgp_add_route(config->bind_address, 0xffffffff);
3206
3207 for (i = 0; i < BGP_NUM_PEERS; i++)
3208 {
3209 if (config->neighbour[i].name[0])
3210 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3211 config->neighbour[i].as, config->neighbour[i].keepalive,
3212 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3213 }
3214 #endif /* BGP */
3215
3216 while (!main_quit || still_busy())
3217 {
3218 int more = 0;
3219 int n;
3220
3221 if (config->reload_config)
3222 {
3223 // Update the config state based on config settings
3224 update_config();
3225 }
3226
3227 #ifdef BGP
3228 bgp_set_poll();
3229 #endif /* BGP */
3230
3231 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3232 STAT(select_called);
3233
3234 TIME = now(NULL);
3235 if (n < 0)
3236 {
3237 if (errno == EINTR ||
3238 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3239 continue;
3240
3241 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3242 break; // exit
3243 }
3244
3245 if (n)
3246 {
3247 struct sockaddr_in addr;
3248 socklen_t alen;
3249 int c, s;
3250 int udp_ready = 0;
3251 int tun_ready = 0;
3252 int cluster_ready = 0;
3253 int udp_pkts = 0;
3254 int tun_pkts = 0;
3255 int cluster_pkts = 0;
3256 #ifdef BGP
3257 uint32_t bgp_events[BGP_NUM_PEERS];
3258 memset(bgp_events, 0, sizeof(bgp_events));
3259 #endif /* BGP */
3260
3261 for (c = n, i = 0; i < c; i++)
3262 {
3263 struct event_data *d = events[i].data.ptr;
3264 switch (d->type)
3265 {
3266 case FD_TYPE_CLI: // CLI connections
3267 {
3268 int cli;
3269
3270 alen = sizeof(addr);
3271 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3272 {
3273 cli_do(cli);
3274 close(cli);
3275 }
3276 else
3277 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3278
3279 n--;
3280 break;
3281 }
3282
3283 // these are handled below, with multiple interleaved reads
3284 case FD_TYPE_CLUSTER: cluster_ready++; break;
3285 case FD_TYPE_TUN: tun_ready++; break;
3286 case FD_TYPE_UDP: udp_ready++; break;
3287
3288 case FD_TYPE_CONTROL: // nsctl commands
3289 alen = sizeof(addr);
3290 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3291 n--;
3292 break;
3293
3294 case FD_TYPE_DAE: // DAE requests
3295 alen = sizeof(addr);
3296 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3297 n--;
3298 break;
3299
3300 case FD_TYPE_RADIUS: // RADIUS response
3301 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3302 if (s >= 0 && config->cluster_iam_master)
3303 processrad(buf, s, d->index);
3304
3305 n--;
3306 break;
3307
3308 #ifdef BGP
3309 case FD_TYPE_BGP:
3310 bgp_events[d->index] = events[i].events;
3311 n--;
3312 break;
3313 #endif /* BGP */
3314
3315 default:
3316 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3317 }
3318 }
3319
3320 #ifdef BGP
3321 bgp_process(bgp_events);
3322 #endif /* BGP */
3323
3324 for (c = 0; n && c < config->multi_read_count; c++)
3325 {
3326 // L2TP
3327 if (udp_ready)
3328 {
3329 alen = sizeof(addr);
3330 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3331 {
3332 processudp(buf, s, &addr);
3333 udp_pkts++;
3334 }
3335 else
3336 {
3337 udp_ready = 0;
3338 n--;
3339 }
3340 }
3341
3342 // incoming IP
3343 if (tun_ready)
3344 {
3345 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3346 {
3347 processtun(buf, s);
3348 tun_pkts++;
3349 }
3350 else
3351 {
3352 tun_ready = 0;
3353 n--;
3354 }
3355 }
3356
3357 // cluster
3358 if (cluster_ready)
3359 {
3360 alen = sizeof(addr);
3361 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3362 {
3363 processcluster(buf, s, addr.sin_addr.s_addr);
3364 cluster_pkts++;
3365 }
3366 else
3367 {
3368 cluster_ready = 0;
3369 n--;
3370 }
3371 }
3372 }
3373
3374 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3375 STAT(multi_read_used);
3376
3377 if (c >= config->multi_read_count)
3378 {
3379 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3380 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3381
3382 STAT(multi_read_exceeded);
3383 more++;
3384 }
3385 }
3386
3387 // Runs on every machine (master and slaves).
3388 if (next_cluster_ping <= TIME)
3389 {
3390 // Check to see which of the cluster is still alive..
3391
3392 cluster_send_ping(basetime); // Only does anything if we're a slave
3393 cluster_check_master(); // ditto.
3394
3395 cluster_heartbeat(); // Only does anything if we're a master.
3396 cluster_check_slaves(); // ditto.
3397
3398 master_update_counts(); // If we're a slave, send our byte counters to our master.
3399
3400 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3401 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3402 else
3403 next_cluster_ping = TIME + config->cluster_hb_interval;
3404 }
3405
3406 if (!config->cluster_iam_master)
3407 continue;
3408
3409 // Run token bucket filtering queue..
3410 // Only run it every 1/10th of a second.
3411 {
3412 static clockt last_run = 0;
3413 if (last_run != TIME)
3414 {
3415 last_run = TIME;
3416 tbf_run_timer();
3417 }
3418 }
3419
3420 // Handle timeouts, retries etc.
3421 {
3422 static double last_clean = 0;
3423 double this_clean;
3424 double diff;
3425
3426 TIME = now(&this_clean);
3427 diff = this_clean - last_clean;
3428
3429 // Run during idle time (after we've handled
3430 // all incoming packets) or every 1/10th sec
3431 if (!more || diff > 0.1)
3432 {
3433 regular_cleanups(diff);
3434 last_clean = this_clean;
3435 }
3436 }
3437
3438 if (*config->accounting_dir)
3439 {
3440 static clockt next_acct = 0;
3441 static clockt next_shut_acct = 0;
3442
3443 if (next_acct <= TIME)
3444 {
3445 // Dump accounting data
3446 next_acct = TIME + ACCT_TIME;
3447 next_shut_acct = TIME + ACCT_SHUT_TIME;
3448 dump_acct_info(1);
3449 }
3450 else if (next_shut_acct <= TIME)
3451 {
3452 // Dump accounting data for shutdown sessions
3453 next_shut_acct = TIME + ACCT_SHUT_TIME;
3454 if (shut_acct_n)
3455 dump_acct_info(0);
3456 }
3457 }
3458 }
3459
3460 // Are we the master and shutting down??
3461 if (config->cluster_iam_master)
3462 cluster_heartbeat(); // Flush any queued changes..
3463
3464 // Ok. Notify everyone we're shutting down. If we're
3465 // the master, this will force an election.
3466 cluster_send_ping(0);
3467
3468 //
3469 // Important!!! We MUST not process any packets past this point!
3470 LOG(1, 0, 0, "Shutdown complete\n");
3471 }
3472
3473 static void stripdomain(char *host)
3474 {
3475 char *p;
3476
3477 if ((p = strchr(host, '.')))
3478 {
3479 char *domain = 0;
3480 char _domain[1024];
3481
3482 // strip off domain
3483 FILE *resolv = fopen("/etc/resolv.conf", "r");
3484 if (resolv)
3485 {
3486 char buf[1024];
3487 char *b;
3488
3489 while (fgets(buf, sizeof(buf), resolv))
3490 {
3491 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3492 continue;
3493
3494 if (!isspace(buf[6]))
3495 continue;
3496
3497 b = buf + 7;
3498 while (isspace(*b)) b++;
3499
3500 if (*b)
3501 {
3502 char *d = b;
3503 while (*b && !isspace(*b)) b++;
3504 *b = 0;
3505 if (buf[0] == 'd') // domain is canonical
3506 {
3507 domain = d;
3508 break;
3509 }
3510
3511 // first search line
3512 if (!domain)
3513 {
3514 // hold, may be subsequent domain line
3515 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3516 domain = _domain;
3517 }
3518 }
3519 }
3520
3521 fclose(resolv);
3522 }
3523
3524 if (domain)
3525 {
3526 int hl = strlen(host);
3527 int dl = strlen(domain);
3528 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3529 host[hl -dl - 1] = 0;
3530 }
3531 else
3532 {
3533 *p = 0; // everything after first dot
3534 }
3535 }
3536 }
3537
3538 // Init data structures
3539 static void initdata(int optdebug, char *optconfig)
3540 {
3541 int i;
3542
3543 if (!(config = shared_malloc(sizeof(configt))))
3544 {
3545 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3546 exit(1);
3547 }
3548
3549 memset(config, 0, sizeof(configt));
3550 time(&config->start_time);
3551 strncpy(config->config_file, optconfig, strlen(optconfig));
3552 config->debug = optdebug;
3553 config->num_tbfs = MAXTBFS;
3554 config->rl_rate = 28; // 28kbps
3555 config->cluster_mcast_ttl = 1;
3556 config->cluster_master_min_adv = 1;
3557 config->ppp_restart_time = 3;
3558 config->ppp_max_configure = 10;
3559 config->ppp_max_failure = 5;
3560 strcpy(config->random_device, RANDOMDEVICE);
3561
3562 log_stream = stderr;
3563
3564 #ifdef RINGBUFFER
3565 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3566 {
3567 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3568 exit(1);
3569 }
3570 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3571 #endif
3572
3573 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3574 {
3575 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3576 exit(1);
3577 }
3578 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3579 {
3580 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3581 exit(1);
3582 }
3583 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3584 {
3585 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3586 exit(1);
3587 }
3588
3589 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3590 {
3591 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3592 exit(1);
3593 }
3594
3595 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3596 {
3597 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3598 exit(1);
3599 }
3600
3601 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3602 {
3603 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3604 exit(1);
3605 }
3606
3607 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3608 {
3609 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3610 exit(1);
3611 }
3612 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3613
3614 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3615 {
3616 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3617 exit(1);
3618 }
3619 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3620
3621 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3622 {
3623 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3624 exit(1);
3625 }
3626 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3627
3628 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3629 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3630 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3631 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3632
3633 // Put all the sessions on the free list marked as undefined.
3634 for (i = 1; i < MAXSESSION; i++)
3635 {
3636 session[i].next = i + 1;
3637 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3638 }
3639 session[MAXSESSION - 1].next = 0;
3640 sessionfree = 1;
3641
3642 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3643 for (i = 1; i < MAXTUNNEL; i++)
3644 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3645
3646 if (!*hostname)
3647 {
3648 // Grab my hostname unless it's been specified
3649 gethostname(hostname, sizeof(hostname));
3650 stripdomain(hostname);
3651 }
3652
3653 _statistics->start_time = _statistics->last_reset = time(NULL);
3654
3655 #ifdef BGP
3656 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3657 {
3658 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3659 exit(1);
3660 }
3661 #endif /* BGP */
3662 }
3663
3664 static int assign_ip_address(sessionidt s)
3665 {
3666 uint32_t i;
3667 int best = -1;
3668 time_t best_time = time_now;
3669 char *u = session[s].user;
3670 char reuse = 0;
3671
3672
3673 CSTAT(assign_ip_address);
3674
3675 for (i = 1; i < ip_pool_size; i++)
3676 {
3677 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3678 continue;
3679
3680 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3681 {
3682 best = i;
3683 reuse = 1;
3684 break;
3685 }
3686
3687 if (ip_address_pool[i].last < best_time)
3688 {
3689 best = i;
3690 if (!(best_time = ip_address_pool[i].last))
3691 break; // never used, grab this one
3692 }
3693 }
3694
3695 if (best < 0)
3696 {
3697 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3698 return 0;
3699 }
3700
3701 session[s].ip = ip_address_pool[best].address;
3702 session[s].ip_pool_index = best;
3703 ip_address_pool[best].assigned = 1;
3704 ip_address_pool[best].last = time_now;
3705 ip_address_pool[best].session = s;
3706 if (session[s].walled_garden)
3707 /* Don't track addresses of users in walled garden (note: this
3708 means that their address isn't "sticky" even if they get
3709 un-gardened). */
3710 ip_address_pool[best].user[0] = 0;
3711 else
3712 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3713
3714 STAT(ip_allocated);
3715 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3716 reuse ? "Reusing" : "Allocating", best);
3717
3718 return 1;
3719 }
3720
3721 static void free_ip_address(sessionidt s)
3722 {
3723 int i = session[s].ip_pool_index;
3724
3725
3726 CSTAT(free_ip_address);
3727
3728 if (!session[s].ip)
3729 return; // what the?
3730
3731 if (i < 0) // Is this actually part of the ip pool?
3732 i = 0;
3733
3734 STAT(ip_freed);
3735 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3736 session[s].ip = 0;
3737 ip_address_pool[i].assigned = 0;
3738 ip_address_pool[i].session = 0;
3739 ip_address_pool[i].last = time_now;
3740 }
3741
3742 //
3743 // Fsck the address pool against the session table.
3744 // Normally only called when we become a master.
3745 //
3746 // This isn't perfect: We aren't keep tracking of which
3747 // users used to have an IP address.
3748 //
3749 void rebuild_address_pool(void)
3750 {
3751 int i;
3752
3753 //
3754 // Zero the IP pool allocation, and build
3755 // a map from IP address to pool index.
3756 for (i = 1; i < MAXIPPOOL; ++i)
3757 {
3758 ip_address_pool[i].assigned = 0;
3759 ip_address_pool[i].session = 0;
3760 if (!ip_address_pool[i].address)
3761 continue;
3762
3763 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3764 }
3765
3766 for (i = 0; i < MAXSESSION; ++i)
3767 {
3768 int ipid;
3769 if (!(session[i].opened && session[i].ip))
3770 continue;
3771
3772 ipid = - lookup_ipmap(htonl(session[i].ip));
3773
3774 if (session[i].ip_pool_index < 0)
3775 {
3776 // Not allocated out of the pool.
3777 if (ipid < 1) // Not found in the pool either? good.
3778 continue;
3779
3780 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3781 i, fmtaddr(session[i].ip, 0), ipid);
3782
3783 // Fall through and process it as part of the pool.
3784 }
3785
3786
3787 if (ipid > MAXIPPOOL || ipid < 0)
3788 {
3789 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3790 ipid = -1;
3791 session[i].ip_pool_index = ipid;
3792 continue;
3793 }
3794
3795 ip_address_pool[ipid].assigned = 1;
3796 ip_address_pool[ipid].session = i;
3797 ip_address_pool[ipid].last = time_now;
3798 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3799 session[i].ip_pool_index = ipid;
3800 cache_ipmap(session[i].ip, i); // Fix the ip map.
3801 }
3802 }
3803
3804 //
3805 // Fix the address pool to match a changed session.
3806 // (usually when the master sends us an update).
3807 static void fix_address_pool(int sid)
3808 {
3809 int ipid;
3810
3811 ipid = session[sid].ip_pool_index;
3812
3813 if (ipid > ip_pool_size)
3814 return; // Ignore it. rebuild_address_pool will fix it up.
3815
3816 if (ip_address_pool[ipid].address != session[sid].ip)
3817 return; // Just ignore it. rebuild_address_pool will take care of it.
3818
3819 ip_address_pool[ipid].assigned = 1;
3820 ip_address_pool[ipid].session = sid;
3821 ip_address_pool[ipid].last = time_now;
3822 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3823 }
3824
3825 //
3826 // Add a block of addresses to the IP pool to hand out.
3827 //
3828 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3829 {
3830 int i;
3831 if (mask == 0)
3832 mask = 0xffffffff; // Host route only.
3833
3834 addr &= mask;
3835
3836 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3837 return ;
3838
3839 for (i = addr ;(i & mask) == addr; ++i)
3840 {
3841 if ((i & 0xff) == 0 || (i&0xff) == 255)
3842 continue; // Skip 0 and broadcast addresses.
3843
3844 ip_address_pool[ip_pool_size].address = i;
3845 ip_address_pool[ip_pool_size].assigned = 0;
3846 ++ip_pool_size;
3847 if (ip_pool_size >= MAXIPPOOL)
3848 {
3849 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3850 return;
3851 }
3852 }
3853 }
3854
3855 // Initialize the IP address pool
3856 static void initippool()
3857 {
3858 FILE *f;
3859 char *p;
3860 char buf[4096];
3861 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3862
3863 if (!(f = fopen(IPPOOLFILE, "r")))
3864 {
3865 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3866 exit(1);
3867 }
3868
3869 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3870 {
3871 char *pool = buf;
3872 buf[4095] = 0; // Force it to be zero terminated/
3873
3874 if (*buf == '#' || *buf == '\n')
3875 continue; // Skip comments / blank lines
3876 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3877 if ((p = (char *)strchr(buf, ':')))
3878 {
3879 in_addr_t src;
3880 *p = '\0';
3881 src = inet_addr(buf);
3882 if (src == INADDR_NONE)
3883 {
3884 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3885 exit(1);
3886 }
3887 // This entry is for a specific IP only
3888 if (src != config->bind_address)
3889 continue;
3890 *p = ':';
3891 pool = p+1;
3892 }
3893 if ((p = (char *)strchr(pool, '/')))
3894 {
3895 // It's a range
3896 int numbits = 0;
3897 in_addr_t start = 0, mask = 0;
3898
3899 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3900 *p++ = 0;
3901 if (!*p || !(numbits = atoi(p)))
3902 {
3903 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3904 continue;
3905 }
3906 start = ntohl(inet_addr(pool));
3907 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3908
3909 // Add a static route for this pool
3910 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3911 fmtaddr(htonl(start), 0), 32 + mask);
3912
3913 routeset(0, start, mask, 0, 1);
3914
3915 add_to_ip_pool(start, mask);
3916 }
3917 else
3918 {
3919 // It's a single ip address
3920 add_to_ip_pool(inet_addr(pool), 0);
3921 }
3922 }
3923 fclose(f);
3924 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3925 }
3926
3927 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3928 {
3929 struct sockaddr_in snoop_addr = {0};
3930 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3931 return;
3932
3933 snoop_addr.sin_family = AF_INET;
3934 snoop_addr.sin_addr.s_addr = destination;
3935 snoop_addr.sin_port = ntohs(port);
3936
3937 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3938 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3939 htons(snoop_addr.sin_port));
3940
3941 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3942 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3943
3944 STAT(packets_snooped);
3945 }
3946
3947 static int dump_session(FILE **f, sessiont *s)
3948 {
3949 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3950 return 1;
3951
3952 if (!*f)
3953 {
3954 char filename[1024];
3955 char timestr[64];
3956 time_t now = time(NULL);
3957
3958 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3959 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3960
3961 if (!(*f = fopen(filename, "w")))
3962 {
3963 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3964 return 0;
3965 }
3966
3967 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3968 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3969 "# host: %s\n"
3970 "# endpoint: %s\n"
3971 "# time: %ld\n"
3972 "# uptime: %ld\n"
3973 "# format: username ip qos uptxoctets downrxoctets\n",
3974 hostname,
3975 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3976 now,
3977 now - basetime);
3978 }
3979
3980 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3981 fprintf(*f, "%s %s %d %u %u\n",
3982 s->user, // username
3983 fmtaddr(htonl(s->ip), 0), // ip
3984 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3985 (uint32_t) s->cin_delta, // uptxoctets
3986 (uint32_t) s->cout_delta); // downrxoctets
3987
3988 s->cin_delta = s->cout_delta = 0;
3989
3990 return 1;
3991 }
3992
3993 static void dump_acct_info(int all)
3994 {
3995 int i;
3996 FILE *f = NULL;
3997
3998
3999 CSTAT(dump_acct_info);
4000
4001 if (shut_acct_n)
4002 {
4003 for (i = 0; i < shut_acct_n; i++)
4004 dump_session(&f, &shut_acct[i]);
4005
4006 shut_acct_n = 0;
4007 }
4008
4009 if (all)
4010 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4011 dump_session(&f, &session[i]);
4012
4013 if (f)
4014 fclose(f);
4015 }
4016
4017 // Main program
4018 int main(int argc, char *argv[])
4019 {
4020 int i;
4021 int optdebug = 0;
4022 char *optconfig = CONFIGFILE;
4023
4024 time(&basetime); // start clock
4025
4026 // scan args
4027 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4028 {
4029 switch (i)
4030 {
4031 case 'd':
4032 if (fork()) exit(0);
4033 setsid();
4034 freopen("/dev/null", "r", stdin);
4035 freopen("/dev/null", "w", stdout);
4036 freopen("/dev/null", "w", stderr);
4037 break;
4038 case 'v':
4039 optdebug++;
4040 break;
4041 case 'c':
4042 optconfig = optarg;
4043 break;
4044 case 'h':
4045 snprintf(hostname, sizeof(hostname), "%s", optarg);
4046 break;
4047 default:
4048 printf("Args are:\n"
4049 "\t-d\t\tDetach from terminal\n"
4050 "\t-c <file>\tConfig file\n"
4051 "\t-h <hostname>\tForce hostname\n"
4052 "\t-v\t\tDebug\n");
4053
4054 return (0);
4055 break;
4056 }
4057 }
4058
4059 // Start the timer routine off
4060 time(&time_now);
4061 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4062 signal(SIGALRM, sigalrm_handler);
4063 siginterrupt(SIGALRM, 0);
4064
4065 initplugins();
4066 initdata(optdebug, optconfig);
4067
4068 init_cli(hostname);
4069 read_config_file();
4070 init_tbf(config->num_tbfs);
4071
4072 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4073 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4074 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4075 {
4076 struct rlimit rlim;
4077 rlim.rlim_cur = RLIM_INFINITY;
4078 rlim.rlim_max = RLIM_INFINITY;
4079 // Remove the maximum core size
4080 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4081 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4082
4083 // Make core dumps go to /tmp
4084 chdir("/tmp");
4085 }
4086
4087 if (config->scheduler_fifo)
4088 {
4089 int ret;
4090 struct sched_param params = {0};
4091 params.sched_priority = 1;
4092
4093 if (get_nprocs() < 2)
4094 {
4095 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4096 config->scheduler_fifo = 0;
4097 }
4098 else
4099 {
4100 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4101 {
4102 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4103 }
4104 else
4105 {
4106 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4107 config->scheduler_fifo = 0;
4108 }
4109 }
4110 }
4111
4112 /* Set up the cluster communications port. */
4113 if (cluster_init() < 0)
4114 exit(1);
4115
4116 inittun();
4117 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4118
4119 initudp();
4120 initrad();
4121 initippool();
4122
4123 // seed prng
4124 {
4125 unsigned seed = time_now ^ getpid();
4126 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4127 srand(seed);
4128 }
4129
4130 signal(SIGHUP, sighup_handler);
4131 signal(SIGCHLD, sigchild_handler);
4132 signal(SIGTERM, shutdown_handler);
4133 signal(SIGINT, shutdown_handler);
4134 signal(SIGQUIT, shutdown_handler);
4135
4136 // Prevent us from getting paged out
4137 if (config->lock_pages)
4138 {
4139 if (!mlockall(MCL_CURRENT))
4140 LOG(1, 0, 0, "Locking pages into memory\n");
4141 else
4142 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4143 }
4144
4145 alarm(1);
4146
4147 // Drop privileges here
4148 if (config->target_uid > 0 && geteuid() == 0)
4149 setuid(config->target_uid);
4150
4151 mainloop();
4152
4153 /* remove plugins (so cleanup code gets run) */
4154 plugins_done();
4155
4156 // Remove the PID file if we wrote it
4157 if (config->wrote_pid && *config->pid_file == '/')
4158 unlink(config->pid_file);
4159
4160 /* kill CLI children */
4161 signal(SIGTERM, SIG_IGN);
4162 kill(0, SIGTERM);
4163 return 0;
4164 }
4165
4166 static void sighup_handler(int sig)
4167 {
4168 if (log_stream)
4169 {
4170 if (log_stream != stderr)
4171 fclose(log_stream);
4172
4173 log_stream = NULL;
4174 }
4175
4176 read_config_file();
4177 }
4178
4179 static void sigalrm_handler(int sig)
4180 {
4181 // Log current traffic stats
4182
4183 snprintf(config->bandwidth, sizeof(config->bandwidth),
4184 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4185 (udp_rx / 1024.0 / 1024.0 * 8),
4186 (eth_tx / 1024.0 / 1024.0 * 8),
4187 (eth_rx / 1024.0 / 1024.0 * 8),
4188 (udp_tx / 1024.0 / 1024.0 * 8),
4189 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4190 udp_rx_pkt, eth_rx_pkt);
4191
4192 udp_tx = udp_rx = 0;
4193 udp_rx_pkt = eth_rx_pkt = 0;
4194 eth_tx = eth_rx = 0;
4195
4196 if (config->dump_speed)
4197 printf("%s\n", config->bandwidth);
4198
4199 // Update the internal time counter
4200 time(&time_now);
4201 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4202 alarm(1);
4203
4204 {
4205 // Run timer hooks
4206 struct param_timer p = { time_now };
4207 run_plugins(PLUGIN_TIMER, &p);
4208 }
4209
4210 }
4211
4212 static void shutdown_handler(int sig)
4213 {
4214 LOG(1, 0, 0, "Shutting down\n");
4215 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4216 }
4217
4218 static void sigchild_handler(int sig)
4219 {
4220 while (waitpid(-1, NULL, WNOHANG) > 0)
4221 ;
4222 }
4223
4224 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4225 {
4226 MD5_CTX ctx;
4227 *challenge_response = NULL;
4228
4229 if (!*config->l2tp_secret)
4230 {
4231 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4232 return;
4233 }
4234
4235 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4236
4237 *challenge_response = calloc(17, 1);
4238
4239 MD5_Init(&ctx);
4240 MD5_Update(&ctx, &id, 1);
4241 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4242 MD5_Update(&ctx, challenge, challenge_length);
4243 MD5_Final(*challenge_response, &ctx);
4244
4245 return;
4246 }
4247
4248 static int facility_value(char *name)
4249 {
4250 int i;
4251 for (i = 0; facilitynames[i].c_name; i++)
4252 {
4253 if (strcmp(facilitynames[i].c_name, name) == 0)
4254 return facilitynames[i].c_val;
4255 }
4256 return 0;
4257 }
4258
4259 static void update_config()
4260 {
4261 int i;
4262 char *p;
4263 static int timeout = 0;
4264 static int interval = 0;
4265
4266 // Update logging
4267 closelog();
4268 syslog_log = 0;
4269 if (log_stream)
4270 {
4271 if (log_stream != stderr)
4272 fclose(log_stream);
4273
4274 log_stream = NULL;
4275 }
4276
4277 if (*config->log_filename)
4278 {
4279 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4280 {
4281 char *p = config->log_filename + 7;
4282 if (*p)
4283 {
4284 openlog("l2tpns", LOG_PID, facility_value(p));
4285 syslog_log = 1;
4286 }
4287 }
4288 else if (strchr(config->log_filename, '/') == config->log_filename)
4289 {
4290 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4291 {
4292 fseek(log_stream, 0, SEEK_END);
4293 setbuf(log_stream, NULL);
4294 }
4295 else
4296 {
4297 log_stream = stderr;
4298 setbuf(log_stream, NULL);
4299 }
4300 }
4301 }
4302 else
4303 {
4304 log_stream = stderr;
4305 setbuf(log_stream, NULL);
4306 }
4307
4308 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4309 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4310
4311 if (config->l2tp_mtu <= 0) config->l2tp_mtu = PPPMTU;
4312 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4313 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4314
4315 // reset MRU/MSS globals
4316 MRU = config->l2tp_mtu - L2TP_HDRS;
4317 MSS = MRU - TCP_HDRS;
4318
4319 // Update radius
4320 config->numradiusservers = 0;
4321 for (i = 0; i < MAXRADSERVER; i++)
4322 if (config->radiusserver[i])
4323 {
4324 config->numradiusservers++;
4325 // Set radius port: if not set, take the port from the
4326 // first radius server. For the first radius server,
4327 // take the #defined default value from l2tpns.h
4328
4329 // test twice, In case someone works with
4330 // a secondary radius server without defining
4331 // a primary one, this will work even then.
4332 if (i > 0 && !config->radiusport[i])
4333 config->radiusport[i] = config->radiusport[i-1];
4334 if (!config->radiusport[i])
4335 config->radiusport[i] = RADPORT;
4336 }
4337
4338 if (!config->numradiusservers)
4339 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4340
4341 // parse radius_authtypes_s
4342 config->radius_authtypes = config->radius_authprefer = 0;
4343 p = config->radius_authtypes_s;
4344 while (p && *p)
4345 {
4346 char *s = strpbrk(p, " \t,");
4347 int type = 0;
4348
4349 if (s)
4350 {
4351 *s++ = 0;
4352 while (*s == ' ' || *s == '\t')
4353 s++;
4354
4355 if (!*s)
4356 s = 0;
4357 }
4358
4359 if (!strncasecmp("chap", p, strlen(p)))
4360 type = AUTHCHAP;
4361 else if (!strncasecmp("pap", p, strlen(p)))
4362 type = AUTHPAP;
4363 else
4364 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4365
4366 config->radius_authtypes |= type;
4367 if (!config->radius_authprefer)
4368 config->radius_authprefer = type;
4369
4370 p = s;
4371 }
4372
4373 if (!config->radius_authtypes)
4374 {
4375 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4376 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4377 }
4378
4379 // normalise radius_authtypes_s
4380 if (config->radius_authprefer == AUTHPAP)
4381 {
4382 strcpy(config->radius_authtypes_s, "pap");
4383 if (config->radius_authtypes & AUTHCHAP)
4384 strcat(config->radius_authtypes_s, ", chap");
4385 }
4386 else
4387 {
4388 strcpy(config->radius_authtypes_s, "chap");
4389 if (config->radius_authtypes & AUTHPAP)
4390 strcat(config->radius_authtypes_s, ", pap");
4391 }
4392
4393 if (!config->radius_dae_port)
4394 config->radius_dae_port = DAEPORT;
4395
4396 // re-initialise the random number source
4397 initrandom(config->random_device);
4398
4399 // Update plugins
4400 for (i = 0; i < MAXPLUGINS; i++)
4401 {
4402 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4403 continue;
4404
4405 if (*config->plugins[i])
4406 {
4407 // Plugin added
4408 add_plugin(config->plugins[i]);
4409 }
4410 else if (*config->old_plugins[i])
4411 {
4412 // Plugin removed
4413 remove_plugin(config->old_plugins[i]);
4414 }
4415 }
4416
4417 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4418 if (!config->multi_read_count) config->multi_read_count = 10;
4419 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4420 if (!*config->cluster_interface)
4421 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4422
4423 if (!config->cluster_hb_interval)
4424 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4425
4426 if (!config->cluster_hb_timeout)
4427 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4428
4429 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4430 {
4431 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4432 // late, ensure we're sufficiently larger than that
4433 int t = 4 * config->cluster_hb_interval + 11;
4434
4435 if (config->cluster_hb_timeout < t)
4436 {
4437 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4438 config->cluster_hb_timeout = t;
4439 }
4440
4441 // Push timing changes to the slaves immediately if we're the master
4442 if (config->cluster_iam_master)
4443 cluster_heartbeat();
4444
4445 interval = config->cluster_hb_interval;
4446 timeout = config->cluster_hb_timeout;
4447 }
4448
4449 // Write PID file
4450 if (*config->pid_file == '/' && !config->wrote_pid)
4451 {
4452 FILE *f;
4453 if ((f = fopen(config->pid_file, "w")))
4454 {
4455 fprintf(f, "%d\n", getpid());
4456 fclose(f);
4457 config->wrote_pid = 1;
4458 }
4459 else
4460 {
4461 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4462 }
4463 }
4464
4465 config->reload_config = 0;
4466 }
4467
4468 static void read_config_file()
4469 {
4470 FILE *f;
4471
4472 if (!config->config_file) return;
4473 if (!(f = fopen(config->config_file, "r")))
4474 {
4475 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4476 return;
4477 }
4478
4479 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4480 cli_do_file(f);
4481 LOG(3, 0, 0, "Done reading config file\n");
4482 fclose(f);
4483 update_config();
4484 }
4485
4486 int sessionsetup(sessionidt s, tunnelidt t)
4487 {
4488 // A session now exists, set it up
4489 in_addr_t ip;
4490 char *user;
4491 sessionidt i;
4492 int r;
4493
4494 CSTAT(sessionsetup);
4495
4496 LOG(3, s, t, "Doing session setup for session\n");
4497
4498 if (!session[s].ip)
4499 {
4500 assign_ip_address(s);
4501 if (!session[s].ip)
4502 {
4503 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4504 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4505 return 0;
4506 }
4507 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4508 fmtaddr(htonl(session[s].ip), 0));
4509 }
4510
4511
4512 // Make sure this is right
4513 session[s].tunnel = t;
4514
4515 // zap old sessions with same IP and/or username
4516 // Don't kill gardened sessions - doing so leads to a DoS
4517 // from someone who doesn't need to know the password
4518 {
4519 ip = session[s].ip;
4520 user = session[s].user;
4521 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4522 {
4523 if (i == s) continue;
4524 if (!session[s].opened) continue;
4525 if (ip == session[i].ip)
4526 {
4527 sessionkill(i, "Duplicate IP address");
4528 continue;
4529 }
4530
4531 if (config->allow_duplicate_users) continue;
4532 if (session[s].walled_garden || session[i].walled_garden) continue;
4533 if (!strcasecmp(user, session[i].user))
4534 sessionkill(i, "Duplicate session for users");
4535 }
4536 }
4537
4538 {
4539 int routed = 0;
4540
4541 // Add the route for this session.
4542 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4543 {
4544 if ((session[s].ip & session[s].route[r].mask) ==
4545 (session[s].route[r].ip & session[s].route[r].mask))
4546 routed++;
4547
4548 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4549 }
4550
4551 // Static IPs need to be routed if not already
4552 // convered by a Framed-Route. Anything else is part
4553 // of the IP address pool and is already routed, it
4554 // just needs to be added to the IP cache.
4555 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4556 if (session[s].ip_pool_index == -1) // static ip
4557 {
4558 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4559 }
4560 else
4561 cache_ipmap(session[s].ip, s);
4562 }
4563
4564 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4565 lcp_open(s, t); // transition to Network phase and send initial IPCP
4566
4567 // Run the plugin's against this new session.
4568 {
4569 struct param_new_session data = { &tunnel[t], &session[s] };
4570 run_plugins(PLUGIN_NEW_SESSION, &data);
4571 }
4572
4573 // Allocate TBFs if throttled
4574 if (session[s].throttle_in || session[s].throttle_out)
4575 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4576
4577 session[s].last_packet = time_now;
4578
4579 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4580 fmtaddr(htonl(session[s].ip), 0),
4581 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4582
4583 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4584
4585 return 1; // RADIUS OK and IP allocated, done...
4586 }
4587
4588 //
4589 // This session just got dropped on us by the master or something.
4590 // Make sure our tables up up to date...
4591 //
4592 int load_session(sessionidt s, sessiont *new)
4593 {
4594 int i;
4595 int newip = 0;
4596
4597 // Sanity checks.
4598 if (new->ip_pool_index >= MAXIPPOOL ||
4599 new->tunnel >= MAXTUNNEL)
4600 {
4601 LOG(0, s, 0, "Strange session update received!\n");
4602 // FIXME! What to do here?
4603 return 0;
4604 }
4605
4606 //
4607 // Ok. All sanity checks passed. Now we're committed to
4608 // loading the new session.
4609 //
4610
4611 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4612
4613 // See if routes/ip cache need updating
4614 if (new->ip != session[s].ip)
4615 newip++;
4616
4617 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4618 if (new->route[i].ip != session[s].route[i].ip ||
4619 new->route[i].mask != session[s].route[i].mask)
4620 newip++;
4621
4622 // needs update
4623 if (newip)
4624 {
4625 int routed = 0;
4626
4627 // remove old routes...
4628 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4629 {
4630 if ((session[s].ip & session[s].route[i].mask) ==
4631 (session[s].route[i].ip & session[s].route[i].mask))
4632 routed++;
4633
4634 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4635 }
4636
4637 // ...ip
4638 if (session[s].ip)
4639 {
4640 if (session[s].ip_pool_index == -1) // static IP
4641 {
4642 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4643 }
4644 else // It's part of the IP pool, remove it manually.
4645 uncache_ipmap(session[s].ip);
4646 }
4647
4648 routed = 0;
4649
4650 // add new routes...
4651 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4652 {
4653 if ((new->ip & new->route[i].mask) ==
4654 (new->route[i].ip & new->route[i].mask))
4655 routed++;
4656
4657 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4658 }
4659
4660 // ...ip
4661 if (new->ip)
4662 {
4663 // If there's a new one, add it.
4664 if (new->ip_pool_index == -1)
4665 {
4666 if (!routed) routeset(s, new->ip, 0, 0, 1);
4667 }
4668 else
4669 cache_ipmap(new->ip, s);
4670 }
4671 }
4672
4673 // check v6 routing
4674 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4675 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4676
4677 // check filters
4678 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4679 {
4680 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4681 new->filter_in = 0;
4682 }
4683
4684 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4685 {
4686 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4687 new->filter_out = 0;
4688 }
4689
4690 if (new->filter_in != session[s].filter_in)
4691 {
4692 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4693 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4694 }
4695
4696 if (new->filter_out != session[s].filter_out)
4697 {
4698 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4699 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4700 }
4701
4702 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4703 // for walking the sessions to forward byte counts to the master.
4704 config->cluster_highest_sessionid = s;
4705
4706 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4707
4708 // Do fixups into address pool.
4709 if (new->ip_pool_index != -1)
4710 fix_address_pool(s);
4711
4712 return 1;
4713 }
4714
4715 static void initplugins()
4716 {
4717 int i;
4718
4719 loaded_plugins = ll_init();
4720 // Initialize the plugins to nothing
4721 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4722 plugins[i] = ll_init();
4723 }
4724
4725 static void *open_plugin(char *plugin_name, int load)
4726 {
4727 char path[256] = "";
4728
4729 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4730 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4731 return dlopen(path, RTLD_NOW);
4732 }
4733
4734 // plugin callback to get a config value
4735 static void *getconfig(char *key, enum config_typet type)
4736 {
4737 int i;
4738
4739 for (i = 0; config_values[i].key; i++)
4740 {
4741 if (!strcmp(config_values[i].key, key))
4742 {
4743 if (config_values[i].type == type)
4744 return ((void *) config) + config_values[i].offset;
4745
4746 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4747 key, type, config_values[i].type);
4748
4749 return 0;
4750 }
4751 }
4752
4753 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4754 return 0;
4755 }
4756
4757 static int add_plugin(char *plugin_name)
4758 {
4759 static struct pluginfuncs funcs = {
4760 _log,
4761 _log_hex,
4762 fmtaddr,
4763 sessionbyuser,
4764 sessiontbysessionidt,
4765 sessionidtbysessiont,
4766 radiusnew,
4767 radiussend,
4768 getconfig,
4769 sessionshutdown,
4770 sessionkill,
4771 throttle_session,
4772 cluster_send_session,
4773 };
4774
4775 void *p = open_plugin(plugin_name, 1);
4776 int (*initfunc)(struct pluginfuncs *);
4777 int i;
4778
4779 if (!p)
4780 {
4781 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4782 return -1;
4783 }
4784
4785 if (ll_contains(loaded_plugins, p))
4786 {
4787 dlclose(p);
4788 return 0; // already loaded
4789 }
4790
4791 {
4792 int *v = dlsym(p, "plugin_api_version");
4793 if (!v || *v != PLUGIN_API_VERSION)
4794 {
4795 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4796 dlclose(p);
4797 return -1;
4798 }
4799 }
4800
4801 if ((initfunc = dlsym(p, "plugin_init")))
4802 {
4803 if (!initfunc(&funcs))
4804 {
4805 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4806 dlclose(p);
4807 return -1;
4808 }
4809 }
4810
4811 ll_push(loaded_plugins, p);
4812
4813 for (i = 0; i < max_plugin_functions; i++)
4814 {
4815 void *x;
4816 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4817 {
4818 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4819 ll_push(plugins[i], x);
4820 }
4821 }
4822
4823 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4824 return 1;
4825 }
4826
4827 static void run_plugin_done(void *plugin)
4828 {
4829 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4830
4831 if (donefunc)
4832 donefunc();
4833 }
4834
4835 static int remove_plugin(char *plugin_name)
4836 {
4837 void *p = open_plugin(plugin_name, 0);
4838 int loaded = 0;
4839
4840 if (!p)
4841 return -1;
4842
4843 if (ll_contains(loaded_plugins, p))
4844 {
4845 int i;
4846 for (i = 0; i < max_plugin_functions; i++)
4847 {
4848 void *x;
4849 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4850 ll_delete(plugins[i], x);
4851 }
4852
4853 ll_delete(loaded_plugins, p);
4854 run_plugin_done(p);
4855 loaded = 1;
4856 }
4857
4858 dlclose(p);
4859 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4860 return loaded;
4861 }
4862
4863 int run_plugins(int plugin_type, void *data)
4864 {
4865 int (*func)(void *data);
4866
4867 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4868 return PLUGIN_RET_ERROR;
4869
4870 ll_reset(plugins[plugin_type]);
4871 while ((func = ll_next(plugins[plugin_type])))
4872 {
4873 int r = func(data);
4874
4875 if (r != PLUGIN_RET_OK)
4876 return r; // stop here
4877 }
4878
4879 return PLUGIN_RET_OK;
4880 }
4881
4882 static void plugins_done()
4883 {
4884 void *p;
4885
4886 ll_reset(loaded_plugins);
4887 while ((p = ll_next(loaded_plugins)))
4888 run_plugin_done(p);
4889 }
4890
4891 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4892 {
4893 struct nsctl request;
4894 struct nsctl response;
4895 int type = unpack_control(&request, buf, len);
4896 int r;
4897 void *p;
4898
4899 if (log_stream && config->debug >= 4)
4900 {
4901 if (type < 0)
4902 {
4903 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4904 fmtaddr(addr->sin_addr.s_addr, 0), type);
4905 }
4906 else
4907 {
4908 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4909 dump_control(&request, log_stream);
4910 }
4911 }
4912
4913 switch (type)
4914 {
4915 case NSCTL_REQ_LOAD:
4916 if (request.argc != 1)
4917 {
4918 response.type = NSCTL_RES_ERR;
4919 response.argc = 1;
4920 response.argv[0] = "name of plugin required";
4921 }
4922 else if ((r = add_plugin(request.argv[0])) < 1)
4923 {
4924 response.type = NSCTL_RES_ERR;
4925 response.argc = 1;
4926 response.argv[0] = !r
4927 ? "plugin already loaded"
4928 : "error loading plugin";
4929 }
4930 else
4931 {
4932 response.type = NSCTL_RES_OK;
4933 response.argc = 0;
4934 }
4935
4936 break;
4937
4938 case NSCTL_REQ_UNLOAD:
4939 if (request.argc != 1)
4940 {
4941 response.type = NSCTL_RES_ERR;
4942 response.argc = 1;
4943 response.argv[0] = "name of plugin required";
4944 }
4945 else if ((r = remove_plugin(request.argv[0])) < 1)
4946 {
4947 response.type = NSCTL_RES_ERR;
4948 response.argc = 1;
4949 response.argv[0] = !r
4950 ? "plugin not loaded"
4951 : "plugin not found";
4952 }
4953 else
4954 {
4955 response.type = NSCTL_RES_OK;
4956 response.argc = 0;
4957 }
4958
4959 break;
4960
4961 case NSCTL_REQ_HELP:
4962 response.type = NSCTL_RES_OK;
4963 response.argc = 0;
4964
4965 ll_reset(loaded_plugins);
4966 while ((p = ll_next(loaded_plugins)))
4967 {
4968 char **help = dlsym(p, "plugin_control_help");
4969 while (response.argc < 0xff && help && *help)
4970 response.argv[response.argc++] = *help++;
4971 }
4972
4973 break;
4974
4975 case NSCTL_REQ_CONTROL:
4976 {
4977 struct param_control param = {
4978 config->cluster_iam_master,
4979 request.argc,
4980 request.argv,
4981 0,
4982 NULL,
4983 };
4984
4985 int r = run_plugins(PLUGIN_CONTROL, &param);
4986
4987 if (r == PLUGIN_RET_ERROR)
4988 {
4989 response.type = NSCTL_RES_ERR;
4990 response.argc = 1;
4991 response.argv[0] = param.additional
4992 ? param.additional
4993 : "error returned by plugin";
4994 }
4995 else if (r == PLUGIN_RET_NOTMASTER)
4996 {
4997 static char msg[] = "must be run on master: 000.000.000.000";
4998
4999 response.type = NSCTL_RES_ERR;
5000 response.argc = 1;
5001 if (config->cluster_master_address)
5002 {
5003 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5004 response.argv[0] = msg;
5005 }
5006 else
5007 {
5008 response.argv[0] = "must be run on master: none elected";
5009 }
5010 }
5011 else if (!(param.response & NSCTL_RESPONSE))
5012 {
5013 response.type = NSCTL_RES_ERR;
5014 response.argc = 1;
5015 response.argv[0] = param.response
5016 ? "unrecognised response value from plugin"
5017 : "unhandled action";
5018 }
5019 else
5020 {
5021 response.type = param.response;
5022 response.argc = 0;
5023 if (param.additional)
5024 {
5025 response.argc = 1;
5026 response.argv[0] = param.additional;
5027 }
5028 }
5029 }
5030
5031 break;
5032
5033 default:
5034 response.type = NSCTL_RES_ERR;
5035 response.argc = 1;
5036 response.argv[0] = "error unpacking control packet";
5037 }
5038
5039 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5040 if (!buf)
5041 {
5042 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5043 return;
5044 }
5045
5046 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5047 if (r > 0)
5048 {
5049 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
5050 if (log_stream && config->debug >= 4)
5051 {
5052 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5053 dump_control(&response, log_stream);
5054 }
5055 }
5056 else
5057 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5058 fmtaddr(addr->sin_addr.s_addr, 0), r);
5059
5060 free(buf);
5061 }
5062
5063 static tunnelidt new_tunnel()
5064 {
5065 tunnelidt i;
5066 for (i = 1; i < MAXTUNNEL; i++)
5067 {
5068 if (tunnel[i].state == TUNNELFREE)
5069 {
5070 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
5071 if (i > config->cluster_highest_tunnelid)
5072 config->cluster_highest_tunnelid = i;
5073 return i;
5074 }
5075 }
5076 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5077 return 0;
5078 }
5079
5080 //
5081 // We're becoming the master. Do any required setup..
5082 //
5083 // This is principally telling all the plugins that we're
5084 // now a master, and telling them about all the sessions
5085 // that are active too..
5086 //
5087 void become_master(void)
5088 {
5089 int s, i;
5090 static struct event_data d[RADIUS_FDS];
5091 struct epoll_event e;
5092
5093 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5094
5095 // running a bunch of iptables commands is slow and can cause
5096 // the master to drop tunnels on takeover--kludge around the
5097 // problem by forking for the moment (note: race)
5098 if (!fork_and_close())
5099 {
5100 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5101 {
5102 if (!session[s].opened) // Not an in-use session.
5103 continue;
5104
5105 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5106 }
5107 exit(0);
5108 }
5109
5110 // add radius fds
5111 e.events = EPOLLIN;
5112 for (i = 0; i < RADIUS_FDS; i++)
5113 {
5114 d[i].type = FD_TYPE_RADIUS;
5115 d[i].index = i;
5116 e.data.ptr = &d[i];
5117
5118 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5119 }
5120 }
5121
5122 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5123 {
5124 int s, i;
5125 int count = 0;
5126 int buckets[64];
5127
5128 if (CLI_HELP_REQUESTED)
5129 return CLI_HELP_NO_ARGS;
5130
5131 time(&time_now);
5132 for (i = 0; i < 64;++i) buckets[i] = 0;
5133
5134 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5135 {
5136 int idle;
5137 if (!session[s].opened)
5138 continue;
5139
5140 idle = time_now - session[s].last_packet;
5141 idle /= 5 ; // In multiples of 5 seconds.
5142 if (idle < 0)
5143 idle = 0;
5144 if (idle > 63)
5145 idle = 63;
5146
5147 ++count;
5148 ++buckets[idle];
5149 }
5150
5151 for (i = 0; i < 63; ++i)
5152 {
5153 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5154 }
5155 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5156 cli_print(cli, "%d total sessions open.", count);
5157 return CLI_OK;
5158 }
5159
5160 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5161 {
5162 int s, i;
5163 int count = 0;
5164 int buckets[64];
5165
5166 if (CLI_HELP_REQUESTED)
5167 return CLI_HELP_NO_ARGS;
5168
5169 time(&time_now);
5170 for (i = 0; i < 64;++i) buckets[i] = 0;
5171
5172 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5173 {
5174 int open = 0, d;
5175 if (!session[s].opened)
5176 continue;
5177
5178 d = time_now - session[s].opened;
5179 if (d < 0)
5180 d = 0;
5181 while (d > 1 && open < 32)
5182 {
5183 ++open;
5184 d >>= 1; // half.
5185 }
5186 ++count;
5187 ++buckets[open];
5188 }
5189
5190 s = 1;
5191 for (i = 0; i < 30; ++i)
5192 {
5193 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5194 s <<= 1;
5195 }
5196 cli_print(cli, "%d total sessions open.", count);
5197 return CLI_OK;
5198 }
5199
5200 /* Unhide an avp.
5201 *
5202 * This unencodes the AVP using the L2TP secret and the previously
5203 * stored random vector. It overwrites the hidden data with the
5204 * unhidden AVP subformat.
5205 */
5206 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5207 {
5208 MD5_CTX ctx;
5209 uint8_t digest[16];
5210 uint8_t *last;
5211 size_t d = 0;
5212 uint16_t m = htons(type);
5213
5214 // Compute initial pad
5215 MD5_Init(&ctx);
5216 MD5_Update(&ctx, (unsigned char *) &m, 2);
5217 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5218 MD5_Update(&ctx, vector, vec_len);
5219 MD5_Final(digest, &ctx);
5220
5221 // pointer to last decoded 16 octets
5222 last = value;
5223
5224 while (len > 0)
5225 {
5226 // calculate a new pad based on the last decoded block
5227 if (d >= sizeof(digest))
5228 {
5229 MD5_Init(&ctx);
5230 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5231 MD5_Update(&ctx, last, sizeof(digest));
5232 MD5_Final(digest, &ctx);
5233
5234 d = 0;
5235 last = value;
5236 }
5237
5238 *value++ ^= digest[d++];
5239 len--;
5240 }
5241 }
5242
5243 int find_filter(char const *name, size_t len)
5244 {
5245 int free = -1;
5246 int i;
5247
5248 for (i = 0; i < MAXFILTER; i++)
5249 {
5250 if (!*ip_filters[i].name)
5251 {
5252 if (free < 0)
5253 free = i;
5254
5255 continue;
5256 }
5257
5258 if (strlen(ip_filters[i].name) != len)
5259 continue;
5260
5261 if (!strncmp(ip_filters[i].name, name, len))
5262 return i;
5263 }
5264
5265 return free;
5266 }
5267
5268 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5269 {
5270 switch (p->op)
5271 {
5272 case FILTER_PORT_OP_EQ: return port == p->port;
5273 case FILTER_PORT_OP_NEQ: return port != p->port;
5274 case FILTER_PORT_OP_GT: return port > p->port;
5275 case FILTER_PORT_OP_LT: return port < p->port;
5276 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5277 }
5278
5279 return 0;
5280 }
5281
5282 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5283 {
5284 switch (op)
5285 {
5286 case FILTER_FLAG_OP_ANY:
5287 return (flags & sflags) || (~flags & cflags);
5288
5289 case FILTER_FLAG_OP_ALL:
5290 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5291
5292 case FILTER_FLAG_OP_EST:
5293 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5294 }
5295
5296 return 0;
5297 }
5298
5299 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5300 {
5301 uint16_t frag_offset;
5302 uint8_t proto;
5303 in_addr_t src_ip;
5304 in_addr_t dst_ip;
5305 uint16_t src_port = 0;
5306 uint16_t dst_port = 0;
5307 uint8_t flags = 0;
5308 ip_filter_rulet *rule;
5309
5310 if (len < 20) // up to end of destination address
5311 return 0;
5312
5313 if ((*buf >> 4) != 4) // IPv4
5314 return 0;
5315
5316 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5317 proto = buf[9];
5318 src_ip = *(in_addr_t *) (buf + 12);
5319 dst_ip = *(in_addr_t *) (buf + 16);
5320
5321 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5322 {
5323 int l = (buf[0] & 0xf) * 4; // length of IP header
5324 if (len < l + 4) // ports
5325 return 0;
5326
5327 src_port = ntohs(*(uint16_t *) (buf + l));
5328 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5329 if (proto == IPPROTO_TCP)
5330 {
5331 if (len < l + 14) // flags
5332 return 0;
5333
5334 flags = buf[l + 13] & 0x3f;
5335 }
5336 }
5337
5338 for (rule = ip_filters[filter].rules; rule->action; rule++)
5339 {
5340 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5341 continue;
5342
5343 if (rule->src_wild != INADDR_BROADCAST &&
5344 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5345 continue;
5346
5347 if (rule->dst_wild != INADDR_BROADCAST &&
5348 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5349 continue;
5350
5351 if (frag_offset)
5352 {
5353 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5354 continue;
5355 }
5356 else
5357 {
5358 if (rule->frag)
5359 continue;
5360
5361 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5362 {
5363 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5364 continue;
5365
5366 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5367 continue;
5368
5369 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5370 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5371 continue;
5372 }
5373 }
5374
5375 // matched
5376 rule->counter++;
5377 return rule->action == FILTER_ACTION_PERMIT;
5378 }
5379
5380 // default deny
5381 return 0;
5382 }