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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 1.136 2005-09-16 05:54:53 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 uint16_t orig;
994 uint32_t sum;
995
996 if ((tcp[13] & 0x3f) & ~(TCP_FLAG_SYN|TCP_FLAG_ACK)) // only want SYN and SYN,ACK
997 return;
998
999 if (tcp + d > buf + len) // short?
1000 return;
1001
1002 opts = tcp + 20;
1003 data = tcp + d;
1004
1005 while (opts < data)
1006 {
1007 if (*opts == 2 && opts[1] == 4) // mss option (2), length 4
1008 {
1009 mss = opts + 2;
1010 if (mss + 2 > data) return; // short?
1011 break;
1012 }
1013
1014 if (*opts == 0) return; // end of options
1015 if (*opts == 1 || !opts[1]) // no op (one byte), or no length (prevent loop)
1016 opts++;
1017 else
1018 opts += opts[1]; // skip over option
1019 }
1020
1021 if (!mss) return; // not found
1022 orig = ntohs(*(uint16_t *) mss);
1023
1024 if (orig <= MSS) return; // mss OK
1025
1026 LOG(5, s, t, "TCP: %s:%u -> %s:%u SYN%s, adjusted mss from %u to %u\n",
1027 fmtaddr(*(in_addr_t *) (buf + 12), 0), ntohs(*(uint16_t *) tcp),
1028 fmtaddr(*(in_addr_t *) (buf + 16), 1), ntohs(*(uint16_t *) (tcp + 2)),
1029 (tcp[13] & TCP_FLAG_ACK) ? ",ACK" : "", orig, MSS);
1030
1031 // set mss
1032 *(int16_t *) mss = MSS;
1033
1034 // adjust checksum (see rfc1141)
1035 sum = orig + (~MSS & 0xffff);
1036 sum += ntohs(*(uint16_t *) (tcp + 16));
1037 sum = (sum & 0xffff) + (sum >> 16);
1038 *(uint16_t *) (tcp + 16) = htons(sum);
1039 }
1040
1041 // process outgoing (to tunnel) IP
1042 //
1043 static void processipout(uint8_t *buf, int len)
1044 {
1045 sessionidt s;
1046 sessiont *sp;
1047 tunnelidt t;
1048 in_addr_t ip;
1049
1050 uint8_t *data = buf; // Keep a copy of the originals.
1051 int size = len;
1052
1053 uint8_t b[MAXETHER + 20];
1054
1055 CSTAT(processipout);
1056
1057 if (len < MIN_IP_SIZE)
1058 {
1059 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
1060 STAT(tun_rx_errors);
1061 return;
1062 }
1063 if (len >= MAXETHER)
1064 {
1065 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
1066 STAT(tun_rx_errors);
1067 return;
1068 }
1069
1070 // Skip the tun header
1071 buf += 4;
1072 len -= 4;
1073
1074 // Got an IP header now
1075 if (*(uint8_t *)(buf) >> 4 != 4)
1076 {
1077 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
1078 return;
1079 }
1080
1081 ip = *(uint32_t *)(buf + 16);
1082 if (!(s = sessionbyip(ip)))
1083 {
1084 // Is this a packet for a session that doesn't exist?
1085 static int rate = 0; // Number of ICMP packets we've sent this second.
1086 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1087
1088 if (last != time_now)
1089 {
1090 last = time_now;
1091 rate = 0;
1092 }
1093
1094 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1095 {
1096 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1097 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4),
1098 config->bind_address ? config->bind_address : my_address, buf, len);
1099 }
1100 return;
1101 }
1102 t = session[s].tunnel;
1103 sp = &session[s];
1104
1105 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1106 if (config->max_packets > 0)
1107 {
1108 if (sess_local[s].last_packet_out == TIME)
1109 {
1110 int max = config->max_packets;
1111
1112 // All packets for throttled sessions are handled by the
1113 // master, so further limit by using the throttle rate.
1114 // A bit of a kludge, since throttle rate is in kbps,
1115 // but should still be generous given our average DSL
1116 // packet size is 200 bytes: a limit of 28kbps equates
1117 // to around 180 packets per second.
1118 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1119 max = sp->throttle_out;
1120
1121 if (++sess_local[s].packets_out > max)
1122 {
1123 sess_local[s].packets_dropped++;
1124 return;
1125 }
1126 }
1127 else
1128 {
1129 if (sess_local[s].packets_dropped)
1130 {
1131 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1132 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1133 sess_local[s].packets_dropped, sess_local[s].packets_out,
1134 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1135 sp->user);
1136 }
1137
1138 sess_local[s].last_packet_out = TIME;
1139 sess_local[s].packets_out = 1;
1140 sess_local[s].packets_dropped = 0;
1141 }
1142 }
1143
1144 // run access-list if any
1145 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1146 return;
1147
1148 // adjust MSS on SYN and SYN,ACK packets with options
1149 if ((ntohs(*(uint16_t *) (buf + 6)) & 0x1fff) == 0 && buf[9] == IPPROTO_TCP) // first tcp fragment
1150 {
1151 int ihl = (buf[0] & 0xf) * 4; // length of IP header
1152 if (len >= ihl + 20 && (buf[ihl + 13] & TCP_FLAG_SYN) && ((buf[ihl + 12] >> 4) > 5))
1153 adjust_tcp_mss(s, t, buf, len, buf + ihl);
1154 }
1155
1156 if (sp->tbf_out)
1157 {
1158 // Are we throttling this session?
1159 if (config->cluster_iam_master)
1160 tbf_queue_packet(sp->tbf_out, data, size);
1161 else
1162 master_throttle_packet(sp->tbf_out, data, size);
1163 return;
1164 }
1165 else if (sp->walled_garden && !config->cluster_iam_master)
1166 {
1167 // We are walled-gardening this
1168 master_garden_packet(s, data, size);
1169 return;
1170 }
1171
1172 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1173
1174 // Add on L2TP header
1175 {
1176 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1177 if (!p) return;
1178 tunnelsend(b, len + (p-b), t); // send it...
1179 }
1180
1181 // Snooping this session, send it to intercept box
1182 if (sp->snoop_ip && sp->snoop_port)
1183 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1184
1185 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1186 sp->cout_delta += len;
1187 sp->pout++;
1188 udp_tx += len;
1189
1190 sess_local[s].cout += len; // To send to master..
1191 sess_local[s].pout++;
1192 }
1193
1194 // process outgoing (to tunnel) IPv6
1195 //
1196 static void processipv6out(uint8_t * buf, int len)
1197 {
1198 sessionidt s;
1199 sessiont *sp;
1200 tunnelidt t;
1201 in_addr_t ip;
1202 struct in6_addr ip6;
1203
1204 uint8_t *data = buf; // Keep a copy of the originals.
1205 int size = len;
1206
1207 uint8_t b[MAXETHER + 20];
1208
1209 CSTAT(processipv6out);
1210
1211 if (len < MIN_IP_SIZE)
1212 {
1213 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1214 STAT(tunnel_tx_errors);
1215 return;
1216 }
1217 if (len >= MAXETHER)
1218 {
1219 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1220 STAT(tunnel_tx_errors);
1221 return;
1222 }
1223
1224 // Skip the tun header
1225 buf += 4;
1226 len -= 4;
1227
1228 // Got an IP header now
1229 if (*(uint8_t *)(buf) >> 4 != 6)
1230 {
1231 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1232 return;
1233 }
1234
1235 ip6 = *(struct in6_addr *)(buf+24);
1236 s = sessionbyipv6(ip6);
1237
1238 if (s == 0)
1239 {
1240 ip = *(uint32_t *)(buf + 32);
1241 s = sessionbyip(ip);
1242 }
1243
1244 if (s == 0)
1245 {
1246 // Is this a packet for a session that doesn't exist?
1247 static int rate = 0; // Number of ICMP packets we've sent this second.
1248 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1249
1250 if (last != time_now)
1251 {
1252 last = time_now;
1253 rate = 0;
1254 }
1255
1256 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1257 {
1258 // FIXME: Should send icmp6 host unreachable
1259 }
1260 return;
1261 }
1262 t = session[s].tunnel;
1263 sp = &session[s];
1264
1265 // FIXME: add DoS prevention/filters?
1266
1267 if (sp->tbf_out)
1268 {
1269 // Are we throttling this session?
1270 if (config->cluster_iam_master)
1271 tbf_queue_packet(sp->tbf_out, data, size);
1272 else
1273 master_throttle_packet(sp->tbf_out, data, size);
1274 return;
1275 }
1276 else if (sp->walled_garden && !config->cluster_iam_master)
1277 {
1278 // We are walled-gardening this
1279 master_garden_packet(s, data, size);
1280 return;
1281 }
1282
1283 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1284
1285 // Add on L2TP header
1286 {
1287 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIPV6);
1288 if (!p) return;
1289 tunnelsend(b, len + (p-b), t); // send it...
1290 }
1291
1292 // Snooping this session, send it to intercept box
1293 if (sp->snoop_ip && sp->snoop_port)
1294 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1295
1296 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1297 sp->cout_delta += len;
1298 sp->pout++;
1299 udp_tx += len;
1300
1301 sess_local[s].cout += len; // To send to master..
1302 sess_local[s].pout++;
1303 }
1304
1305 //
1306 // Helper routine for the TBF filters.
1307 // Used to send queued data in to the user!
1308 //
1309 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1310 {
1311 sessiont *sp;
1312 tunnelidt t;
1313 in_addr_t ip;
1314
1315 uint8_t b[MAXETHER + 20];
1316
1317 if (len < 0 || len > MAXETHER)
1318 {
1319 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1320 return;
1321 }
1322
1323 // Skip the tun header
1324 buf += 4;
1325 len -= 4;
1326
1327 ip = *(in_addr_t *)(buf + 16);
1328
1329 if (!session[s].ip)
1330 return;
1331
1332 t = session[s].tunnel;
1333 sp = &session[s];
1334
1335 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1336
1337 // Add on L2TP header
1338 {
1339 uint8_t *p = makeppp(b, sizeof(b), buf, len, s, t, PPPIP);
1340 if (!p) return;
1341 tunnelsend(b, len + (p-b), t); // send it...
1342 }
1343
1344 // Snooping this session.
1345 if (sp->snoop_ip && sp->snoop_port)
1346 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1347
1348 increment_counter(&sp->cout, &sp->cout_wrap, len); // byte count
1349 sp->cout_delta += len;
1350 sp->pout++;
1351 udp_tx += len;
1352
1353 sess_local[s].cout += len; // To send to master..
1354 sess_local[s].pout++;
1355 }
1356
1357 // add an AVP (16 bit)
1358 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1359 {
1360 uint16_t l = (m ? 0x8008 : 0x0008);
1361 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1362 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1363 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1364 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1365 c->length += 8;
1366 }
1367
1368 // add an AVP (32 bit)
1369 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1370 {
1371 uint16_t l = (m ? 0x800A : 0x000A);
1372 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1373 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1374 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1375 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1376 c->length += 10;
1377 }
1378
1379 // add an AVP (string)
1380 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1381 {
1382 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1383 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1384 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1385 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1386 memcpy(c->buf + c->length + 6, val, strlen(val));
1387 c->length += 6 + strlen(val);
1388 }
1389
1390 // add a binary AVP
1391 static void controlb(controlt * c, uint16_t avp, uint8_t *val, unsigned int len, uint8_t m)
1392 {
1393 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1394 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1395 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1396 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1397 memcpy(c->buf + c->length + 6, val, len);
1398 c->length += 6 + len;
1399 }
1400
1401 // new control connection
1402 static controlt *controlnew(uint16_t mtype)
1403 {
1404 controlt *c;
1405 if (!controlfree)
1406 c = malloc(sizeof(controlt));
1407 else
1408 {
1409 c = controlfree;
1410 controlfree = c->next;
1411 }
1412 assert(c);
1413 c->next = 0;
1414 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1415 c->length = 12;
1416 control16(c, 0, mtype, 1);
1417 return c;
1418 }
1419
1420 // send zero block if nothing is waiting
1421 // (ZLB send).
1422 static void controlnull(tunnelidt t)
1423 {
1424 uint8_t buf[12];
1425 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1426 return;
1427
1428 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1429 *(uint16_t *) (buf + 2) = htons(12); // length
1430 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1431 *(uint16_t *) (buf + 6) = htons(0); // session
1432 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1433 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1434 tunnelsend(buf, 12, t);
1435 }
1436
1437 // add a control message to a tunnel, and send if within window
1438 static void controladd(controlt *c, sessionidt far, tunnelidt t)
1439 {
1440 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1441 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1442 *(uint16_t *) (c->buf + 6) = htons(far); // session
1443 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1444 tunnel[t].ns++; // advance sequence
1445 // link in message in to queue
1446 if (tunnel[t].controlc)
1447 tunnel[t].controle->next = c;
1448 else
1449 tunnel[t].controls = c;
1450
1451 tunnel[t].controle = c;
1452 tunnel[t].controlc++;
1453
1454 // send now if space in window
1455 if (tunnel[t].controlc <= tunnel[t].window)
1456 {
1457 tunnel[t].try = 0; // first send
1458 tunnelsend(c->buf, c->length, t);
1459 }
1460 }
1461
1462 //
1463 // Throttle or Unthrottle a session
1464 //
1465 // Throttle the data from/to through a session to no more than
1466 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1467 // user).
1468 //
1469 // If either value is -1, the current value is retained for that
1470 // direction.
1471 //
1472 void throttle_session(sessionidt s, int rate_in, int rate_out)
1473 {
1474 if (!session[s].opened)
1475 return; // No-one home.
1476
1477 if (!*session[s].user)
1478 return; // User not logged in
1479
1480 if (rate_in >= 0)
1481 {
1482 int bytes = rate_in * 1024 / 8; // kbits to bytes
1483 if (session[s].tbf_in)
1484 free_tbf(session[s].tbf_in);
1485
1486 if (rate_in > 0)
1487 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1488 else
1489 session[s].tbf_in = 0;
1490
1491 session[s].throttle_in = rate_in;
1492 }
1493
1494 if (rate_out >= 0)
1495 {
1496 int bytes = rate_out * 1024 / 8;
1497 if (session[s].tbf_out)
1498 free_tbf(session[s].tbf_out);
1499
1500 if (rate_out > 0)
1501 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1502 else
1503 session[s].tbf_out = 0;
1504
1505 session[s].throttle_out = rate_out;
1506 }
1507 }
1508
1509 // add/remove filters from session (-1 = no change)
1510 void filter_session(sessionidt s, int filter_in, int filter_out)
1511 {
1512 if (!session[s].opened)
1513 return; // No-one home.
1514
1515 if (!*session[s].user)
1516 return; // User not logged in
1517
1518 // paranoia
1519 if (filter_in > MAXFILTER) filter_in = -1;
1520 if (filter_out > MAXFILTER) filter_out = -1;
1521 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1522 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1523
1524 if (filter_in >= 0)
1525 {
1526 if (session[s].filter_in)
1527 ip_filters[session[s].filter_in - 1].used--;
1528
1529 if (filter_in > 0)
1530 ip_filters[filter_in - 1].used++;
1531
1532 session[s].filter_in = filter_in;
1533 }
1534
1535 if (filter_out >= 0)
1536 {
1537 if (session[s].filter_out)
1538 ip_filters[session[s].filter_out - 1].used--;
1539
1540 if (filter_out > 0)
1541 ip_filters[filter_out - 1].used++;
1542
1543 session[s].filter_out = filter_out;
1544 }
1545 }
1546
1547 // start tidy shutdown of session
1548 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1549 {
1550 int walled_garden = session[s].walled_garden;
1551
1552
1553 CSTAT(sessionshutdown);
1554
1555 if (!session[s].opened)
1556 {
1557 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1558 return; // not a live session
1559 }
1560
1561 if (!session[s].die)
1562 {
1563 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1564 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1565 run_plugins(PLUGIN_KILL_SESSION, &data);
1566 }
1567
1568 if (session[s].ip && !walled_garden && !session[s].die)
1569 {
1570 // RADIUS Stop message
1571 uint16_t r = radiusnew(s);
1572 if (r)
1573 {
1574 // stop, if not already trying
1575 if (radius[r].state != RADIUSSTOP)
1576 radiussend(r, RADIUSSTOP);
1577 }
1578 else
1579 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1580
1581 // Save counters to dump to accounting file
1582 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1583 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1584 }
1585
1586 if (session[s].ip)
1587 { // IP allocated, clear and unroute
1588 int r;
1589 int routed = 0;
1590 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1591 {
1592 if ((session[s].ip & session[s].route[r].mask) ==
1593 (session[s].route[r].ip & session[s].route[r].mask))
1594 routed++;
1595
1596 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1597 session[s].route[r].ip = 0;
1598 }
1599
1600 if (session[s].ip_pool_index == -1) // static ip
1601 {
1602 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1603 session[s].ip = 0;
1604 }
1605 else
1606 free_ip_address(s);
1607
1608 // unroute IPv6, if setup
1609 if (session[s].ppp.ipv6cp == Opened && session[s].ipv6prefixlen)
1610 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1611 }
1612
1613 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1614 throttle_session(s, 0, 0);
1615
1616 if (result)
1617 { // Send CDN
1618 controlt *c = controlnew(14); // sending CDN
1619 if (error)
1620 {
1621 uint8_t buf[4];
1622 *(uint16_t *) buf = htons(result);
1623 *(uint16_t *) (buf+2) = htons(error);
1624 controlb(c, 1, buf, 4, 1);
1625 }
1626 else
1627 control16(c, 1, result, 1);
1628
1629 control16(c, 14, s, 1); // assigned session (our end)
1630 controladd(c, session[s].far, session[s].tunnel); // send the message
1631 }
1632
1633 if (!session[s].die)
1634 session[s].die = TIME + 150; // Clean up in 15 seconds
1635
1636 // update filter refcounts
1637 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1638 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1639
1640 // clear PPP state
1641 memset(&session[s].ppp, 0, sizeof(session[s].ppp));
1642 sess_local[s].lcp.restart = 0;
1643 sess_local[s].ipcp.restart = 0;
1644 sess_local[s].ipv6cp.restart = 0;
1645 sess_local[s].ccp.restart = 0;
1646
1647 cluster_send_session(s);
1648 }
1649
1650 void sendipcp(sessionidt s, tunnelidt t)
1651 {
1652 uint8_t buf[MAXETHER];
1653 uint8_t *q;
1654
1655 CSTAT(sendipcp);
1656 LOG(3, s, t, "IPCP: send ConfigReq\n");
1657
1658 if (!session[s].unique_id)
1659 {
1660 if (!++last_id) ++last_id; // skip zero
1661 session[s].unique_id = last_id;
1662 }
1663
1664 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPCP);
1665 if (!q) return;
1666
1667 *q = ConfigReq;
1668 q[1] = session[s].unique_id & 0xf; // ID, dont care, we only send one type of request
1669 *(uint16_t *) (q + 2) = htons(10); // packet length
1670 q[4] = 3; // ip address option
1671 q[5] = 6; // option length
1672 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1673 config->bind_address ? config->bind_address :
1674 my_address; // send my IP
1675
1676 tunnelsend(buf, 10 + (q - buf), t); // send it
1677 }
1678
1679 void sendipv6cp(sessionidt s, tunnelidt t)
1680 {
1681 uint8_t buf[MAXETHER];
1682 uint8_t *q;
1683
1684 CSTAT(sendipv6cp);
1685 LOG(3, s, t, "IPV6CP: send ConfigReq\n");
1686
1687 q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPIPV6CP);
1688 if (!q) return;
1689
1690 *q = ConfigReq;
1691 q[1] = session[s].unique_id & 0xf; // ID, don't care, we
1692 // only send one type
1693 // of request
1694 *(uint16_t *) (q + 2) = htons(14);
1695 q[4] = 1; // interface identifier option
1696 q[5] = 10; // option length
1697 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1698 *(uint32_t *) (q + 10) = 0;
1699 q[13] = 1;
1700
1701 tunnelsend(buf, 14 + (q - buf), t); // send it
1702 }
1703
1704 static void sessionclear(sessionidt s)
1705 {
1706 memset(&session[s], 0, sizeof(session[s]));
1707 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1708 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1709
1710 session[s].tunnel = T_FREE; // Mark it as free.
1711 session[s].next = sessionfree;
1712 sessionfree = s;
1713 }
1714
1715 // kill a session now
1716 void sessionkill(sessionidt s, char *reason)
1717 {
1718
1719 CSTAT(sessionkill);
1720
1721 if (!session[s].opened) // not alive
1722 return;
1723
1724 if (session[s].next)
1725 {
1726 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1727 return;
1728 }
1729
1730 session[s].die = TIME;
1731 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1732 if (sess_local[s].radius)
1733 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1734
1735 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1736 sessionclear(s);
1737 cluster_send_session(s);
1738 }
1739
1740 static void tunnelclear(tunnelidt t)
1741 {
1742 if (!t) return;
1743 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1744 tunnel[t].state = TUNNELFREE;
1745 }
1746
1747 // kill a tunnel now
1748 static void tunnelkill(tunnelidt t, char *reason)
1749 {
1750 sessionidt s;
1751 controlt *c;
1752
1753 CSTAT(tunnelkill);
1754
1755 tunnel[t].state = TUNNELDIE;
1756
1757 // free control messages
1758 while ((c = tunnel[t].controls))
1759 {
1760 controlt * n = c->next;
1761 tunnel[t].controls = n;
1762 tunnel[t].controlc--;
1763 c->next = controlfree;
1764 controlfree = c;
1765 }
1766 // kill sessions
1767 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1768 if (session[s].tunnel == t)
1769 sessionkill(s, reason);
1770
1771 // free tunnel
1772 tunnelclear(t);
1773 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1774 cli_tunnel_actions[t].action = 0;
1775 cluster_send_tunnel(t);
1776 }
1777
1778 // shut down a tunnel cleanly
1779 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1780 {
1781 sessionidt s;
1782
1783 CSTAT(tunnelshutdown);
1784
1785 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1786 {
1787 // never set up, can immediately kill
1788 tunnelkill(t, reason);
1789 return;
1790 }
1791 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1792
1793 // close session
1794 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1795 if (session[s].tunnel == t)
1796 sessionshutdown(s, reason, 0, 0);
1797
1798 tunnel[t].state = TUNNELDIE;
1799 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1800 cluster_send_tunnel(t);
1801 // TBA - should we wait for sessions to stop?
1802 if (result)
1803 {
1804 controlt *c = controlnew(4); // sending StopCCN
1805 if (error)
1806 {
1807 uint8_t buf[64];
1808 int l = 4;
1809 *(uint16_t *) buf = htons(result);
1810 *(uint16_t *) (buf+2) = htons(error);
1811 if (msg)
1812 {
1813 int m = strlen(msg);
1814 if (m + 4 > sizeof(buf))
1815 m = sizeof(buf) - 4;
1816
1817 memcpy(buf+4, msg, m);
1818 l += m;
1819 }
1820
1821 controlb(c, 1, buf, l, 1);
1822 }
1823 else
1824 control16(c, 1, result, 1);
1825
1826 control16(c, 9, t, 1); // assigned tunnel (our end)
1827 controladd(c, 0, t); // send the message
1828 }
1829 }
1830
1831 // read and process packet on tunnel (UDP)
1832 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr)
1833 {
1834 uint8_t *chapresponse = NULL;
1835 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1836 uint8_t *p = buf + 2;
1837
1838
1839 CSTAT(processudp);
1840
1841 udp_rx += len;
1842 udp_rx_pkt++;
1843 LOG_HEX(5, "UDP Data", buf, len);
1844 STAT(tunnel_rx_packets);
1845 INC_STAT(tunnel_rx_bytes, len);
1846 if (len < 6)
1847 {
1848 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1849 STAT(tunnel_rx_errors);
1850 return;
1851 }
1852 if ((buf[1] & 0x0F) != 2)
1853 {
1854 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1855 STAT(tunnel_rx_errors);
1856 return;
1857 }
1858 if (*buf & 0x40)
1859 { // length
1860 l = ntohs(*(uint16_t *) p);
1861 p += 2;
1862 }
1863 t = ntohs(*(uint16_t *) p);
1864 p += 2;
1865 s = ntohs(*(uint16_t *) p);
1866 p += 2;
1867 if (s >= MAXSESSION)
1868 {
1869 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1870 STAT(tunnel_rx_errors);
1871 return;
1872 }
1873 if (t >= MAXTUNNEL)
1874 {
1875 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1876 STAT(tunnel_rx_errors);
1877 return;
1878 }
1879 if (*buf & 0x08)
1880 { // ns/nr
1881 ns = ntohs(*(uint16_t *) p);
1882 p += 2;
1883 nr = ntohs(*(uint16_t *) p);
1884 p += 2;
1885 }
1886 if (*buf & 0x02)
1887 { // offset
1888 uint16_t o = ntohs(*(uint16_t *) p);
1889 p += o + 2;
1890 }
1891 if ((p - buf) > l)
1892 {
1893 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1894 STAT(tunnel_rx_errors);
1895 return;
1896 }
1897 l -= (p - buf);
1898
1899 // used to time out old tunnels
1900 if (t && tunnel[t].state == TUNNELOPEN)
1901 tunnel[t].lastrec = time_now;
1902
1903 if (*buf & 0x80)
1904 { // control
1905 uint16_t message = 0xFFFF; // message type
1906 uint8_t fatal = 0;
1907 uint8_t mandatory = 0;
1908 uint16_t asession = 0; // assigned session
1909 uint32_t amagic = 0; // magic number
1910 uint8_t aflags = 0; // flags from last LCF
1911 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1912 char called[MAXTEL] = ""; // called number
1913 char calling[MAXTEL] = ""; // calling number
1914
1915 if (!config->cluster_iam_master)
1916 {
1917 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1918 return;
1919 }
1920
1921 // control messages must have bits 0x80|0x40|0x08
1922 // (type, length and sequence) set, and bits 0x02|0x01
1923 // (offset and priority) clear
1924 if ((*buf & 0xCB) != 0xC8)
1925 {
1926 LOG(1, s, t, "Bad control header %02X\n", *buf);
1927 STAT(tunnel_rx_errors);
1928 return;
1929 }
1930
1931 // check for duplicate tunnel open message
1932 if (!t && ns == 0)
1933 {
1934 int i;
1935
1936 //
1937 // Is this a duplicate of the first packet? (SCCRQ)
1938 //
1939 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1940 {
1941 if (tunnel[i].state != TUNNELOPENING ||
1942 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1943 tunnel[i].port != ntohs(addr->sin_port) )
1944 continue;
1945 t = i;
1946 LOG(3, s, t, "Duplicate SCCRQ?\n");
1947 break;
1948 }
1949 }
1950
1951 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1952 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1953
1954 // if no tunnel specified, assign one
1955 if (!t)
1956 {
1957 if (!(t = new_tunnel()))
1958 {
1959 LOG(1, 0, 0, "No more tunnels\n");
1960 STAT(tunnel_overflow);
1961 return;
1962 }
1963 tunnelclear(t);
1964 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1965 tunnel[t].port = ntohs(addr->sin_port);
1966 tunnel[t].window = 4; // default window
1967 STAT(tunnel_created);
1968 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1969 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1970 }
1971
1972 // If the 'ns' just received is not the 'nr' we're
1973 // expecting, just send an ack and drop it.
1974 //
1975 // if 'ns' is less, then we got a retransmitted packet.
1976 // if 'ns' is greater than missed a packet. Either way
1977 // we should ignore it.
1978 if (ns != tunnel[t].nr)
1979 {
1980 // is this the sequence we were expecting?
1981 STAT(tunnel_rx_errors);
1982 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1983 t, ns, tunnel[t].nr);
1984
1985 if (l) // Is this not a ZLB?
1986 controlnull(t);
1987 return;
1988 }
1989
1990 // check sequence of this message
1991 {
1992 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1993 // some to clear maybe?
1994 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1995 {
1996 controlt *c = tunnel[t].controls;
1997 tunnel[t].controls = c->next;
1998 tunnel[t].controlc--;
1999 c->next = controlfree;
2000 controlfree = c;
2001 skip--;
2002 tunnel[t].try = 0; // we have progress
2003 }
2004
2005 // receiver advance (do here so quoted correctly in any sends below)
2006 if (l) tunnel[t].nr = (ns + 1);
2007 if (skip < 0) skip = 0;
2008 if (skip < tunnel[t].controlc)
2009 {
2010 // some control packets can now be sent that were previous stuck out of window
2011 int tosend = tunnel[t].window - skip;
2012 controlt *c = tunnel[t].controls;
2013 while (c && skip)
2014 {
2015 c = c->next;
2016 skip--;
2017 }
2018 while (c && tosend)
2019 {
2020 tunnel[t].try = 0; // first send
2021 tunnelsend(c->buf, c->length, t);
2022 c = c->next;
2023 tosend--;
2024 }
2025 }
2026 if (!tunnel[t].controlc)
2027 tunnel[t].retry = 0; // caught up
2028 }
2029 if (l)
2030 { // if not a null message
2031 int result = 0;
2032 int error = 0;
2033 char *msg = 0;
2034
2035 // process AVPs
2036 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
2037 {
2038 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
2039 uint8_t *b = p;
2040 uint8_t flags = *p;
2041 uint16_t mtype;
2042 if (n > l)
2043 {
2044 LOG(1, s, t, "Invalid length in AVP\n");
2045 STAT(tunnel_rx_errors);
2046 return;
2047 }
2048 p += n; // next
2049 l -= n;
2050 if (flags & 0x3C) // reserved bits, should be clear
2051 {
2052 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
2053 fatal = flags;
2054 result = 2; // general error
2055 error = 3; // reserved field non-zero
2056 msg = 0;
2057 continue; // next
2058 }
2059 b += 2;
2060 if (*(uint16_t *) (b))
2061 {
2062 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
2063 fatal = flags;
2064 result = 2; // general error
2065 error = 6; // generic vendor-specific error
2066 msg = "unsupported vendor-specific";
2067 continue; // next
2068 }
2069 b += 2;
2070 mtype = ntohs(*(uint16_t *) (b));
2071 b += 2;
2072 n -= 6;
2073
2074 if (flags & 0x40)
2075 {
2076 uint16_t orig_len;
2077
2078 // handle hidden AVPs
2079 if (!*config->l2tp_secret)
2080 {
2081 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
2082 fatal = flags;
2083 result = 2; // general error
2084 error = 6; // generic vendor-specific error
2085 msg = "secret not specified";
2086 continue;
2087 }
2088 if (!session[s].random_vector_length)
2089 {
2090 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
2091 fatal = flags;
2092 result = 2; // general error
2093 error = 6; // generic
2094 msg = "no random vector";
2095 continue;
2096 }
2097 if (n < 8)
2098 {
2099 LOG(2, s, t, "Short hidden AVP.\n");
2100 fatal = flags;
2101 result = 2; // general error
2102 error = 2; // length is wrong
2103 msg = 0;
2104 continue;
2105 }
2106
2107 // Unhide the AVP
2108 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2109
2110 orig_len = ntohs(*(uint16_t *) b);
2111 if (orig_len > n + 2)
2112 {
2113 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2114 orig_len, n);
2115
2116 fatal = flags;
2117 result = 2; // general error
2118 error = 2; // length is wrong
2119 msg = 0;
2120 continue;
2121 }
2122
2123 b += 2;
2124 n = orig_len;
2125 }
2126
2127 LOG(4, s, t, " AVP %d (%s) len %d%s%s\n", mtype, l2tp_avp_name(mtype), n,
2128 flags & 0x40 ? ", hidden" : "", flags & 0x80 ? ", mandatory" : "");
2129
2130 switch (mtype)
2131 {
2132 case 0: // message type
2133 message = ntohs(*(uint16_t *) b);
2134 mandatory = flags & 0x80;
2135 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_code(message));
2136 break;
2137 case 1: // result code
2138 {
2139 uint16_t rescode = ntohs(*(uint16_t *) b);
2140 const char* resdesc = "(unknown)";
2141 if (message == 4)
2142 { /* StopCCN */
2143 resdesc = l2tp_stopccn_result_code(rescode);
2144 }
2145 else if (message == 14)
2146 { /* CDN */
2147 resdesc = l2tp_cdn_result_code(rescode);
2148 }
2149
2150 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2151 if (n >= 4)
2152 {
2153 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2154 LOG(4, s, t, " Error Code %d: %s\n", errcode, l2tp_error_code(errcode));
2155 }
2156 if (n > 4)
2157 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2158
2159 break;
2160 }
2161 break;
2162 case 2: // protocol version
2163 {
2164 version = ntohs(*(uint16_t *) (b));
2165 LOG(4, s, t, " Protocol version = %d\n", version);
2166 if (version && version != 0x0100)
2167 { // allow 0.0 and 1.0
2168 LOG(1, s, t, " Bad protocol version %04X\n", version);
2169 fatal = flags;
2170 result = 5; // unspported protocol version
2171 error = 0x0100; // supported version
2172 msg = 0;
2173 continue; // next
2174 }
2175 }
2176 break;
2177 case 3: // framing capabilities
2178 // LOG(4, s, t, "Framing capabilities\n");
2179 break;
2180 case 4: // bearer capabilities
2181 // LOG(4, s, t, "Bearer capabilities\n");
2182 break;
2183 case 5: // tie breaker
2184 // We never open tunnels, so we don't care about tie breakers
2185 // LOG(4, s, t, "Tie breaker\n");
2186 continue;
2187 case 6: // firmware revision
2188 // LOG(4, s, t, "Firmware revision\n");
2189 break;
2190 case 7: // host name
2191 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2192 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2193 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2194 // TBA - to send to RADIUS
2195 break;
2196 case 8: // vendor name
2197 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2198 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2199 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2200 break;
2201 case 9: // assigned tunnel
2202 tunnel[t].far = ntohs(*(uint16_t *) (b));
2203 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2204 break;
2205 case 10: // rx window
2206 tunnel[t].window = ntohs(*(uint16_t *) (b));
2207 if (!tunnel[t].window)
2208 tunnel[t].window = 1; // window of 0 is silly
2209 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2210 break;
2211 case 11: // Challenge
2212 {
2213 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2214 build_chap_response(b, 2, n, &chapresponse);
2215 }
2216 break;
2217 case 13: // Response
2218 // Why did they send a response? We never challenge.
2219 LOG(2, s, t, " received unexpected challenge response\n");
2220 break;
2221
2222 case 14: // assigned session
2223 asession = session[s].far = ntohs(*(uint16_t *) (b));
2224 LOG(4, s, t, " assigned session = %d\n", asession);
2225 break;
2226 case 15: // call serial number
2227 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2228 break;
2229 case 18: // bearer type
2230 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2231 // TBA - for RADIUS
2232 break;
2233 case 19: // framing type
2234 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2235 // TBA
2236 break;
2237 case 21: // called number
2238 memset(called, 0, sizeof(called));
2239 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2240 LOG(4, s, t, " Called <%s>\n", called);
2241 break;
2242 case 22: // calling number
2243 memset(calling, 0, sizeof(calling));
2244 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2245 LOG(4, s, t, " Calling <%s>\n", calling);
2246 break;
2247 case 23: // subtype
2248 break;
2249 case 24: // tx connect speed
2250 if (n == 4)
2251 {
2252 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2253 }
2254 else
2255 {
2256 // AS5300s send connect speed as a string
2257 char tmp[30];
2258 memset(tmp, 0, sizeof(tmp));
2259 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2260 session[s].tx_connect_speed = atol(tmp);
2261 }
2262 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2263 break;
2264 case 38: // rx connect speed
2265 if (n == 4)
2266 {
2267 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2268 }
2269 else
2270 {
2271 // AS5300s send connect speed as a string
2272 char tmp[30];
2273 memset(tmp, 0, sizeof(tmp));
2274 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2275 session[s].rx_connect_speed = atol(tmp);
2276 }
2277 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2278 break;
2279 case 25: // Physical Channel ID
2280 {
2281 uint32_t tmp = ntohl(*(uint32_t *) b);
2282 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2283 break;
2284 }
2285 case 29: // Proxy Authentication Type
2286 {
2287 uint16_t atype = ntohs(*(uint16_t *)b);
2288 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, ppp_auth_type(atype));
2289 break;
2290 }
2291 case 30: // Proxy Authentication Name
2292 {
2293 char authname[64];
2294 memset(authname, 0, sizeof(authname));
2295 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2296 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2297 authname);
2298 break;
2299 }
2300 case 31: // Proxy Authentication Challenge
2301 {
2302 LOG(4, s, t, " Proxy Auth Challenge\n");
2303 break;
2304 }
2305 case 32: // Proxy Authentication ID
2306 {
2307 uint16_t authid = ntohs(*(uint16_t *)(b));
2308 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2309 break;
2310 }
2311 case 33: // Proxy Authentication Response
2312 LOG(4, s, t, " Proxy Auth Response\n");
2313 break;
2314 case 27: // last sent lcp
2315 { // find magic number
2316 uint8_t *p = b, *e = p + n;
2317 while (p + 1 < e && p[1] && p + p[1] <= e)
2318 {
2319 if (*p == 5 && p[1] == 6) // Magic-Number
2320 amagic = ntohl(*(uint32_t *) (p + 2));
2321 else if (*p == 7) // Protocol-Field-Compression
2322 aflags |= SESSIONPFC;
2323 else if (*p == 8) // Address-and-Control-Field-Compression
2324 aflags |= SESSIONACFC;
2325 p += p[1];
2326 }
2327 }
2328 break;
2329 case 28: // last recv lcp confreq
2330 break;
2331 case 26: // Initial Received LCP CONFREQ
2332 break;
2333 case 39: // seq required - we control it as an LNS anyway...
2334 break;
2335 case 36: // Random Vector
2336 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2337 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2338 if (n > sizeof(session[s].random_vector))
2339 n = sizeof(session[s].random_vector);
2340 memcpy(session[s].random_vector, b, n);
2341 session[s].random_vector_length = n;
2342 break;
2343 default:
2344 {
2345 static char e[] = "unknown AVP 0xXXXX";
2346 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2347 fatal = flags;
2348 result = 2; // general error
2349 error = 8; // unknown mandatory AVP
2350 sprintf((msg = e) + 14, "%04x", mtype);
2351 continue; // next
2352 }
2353 }
2354 }
2355 // process message
2356 if (fatal & 0x80)
2357 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2358 else
2359 switch (message)
2360 {
2361 case 1: // SCCRQ - Start Control Connection Request
2362 tunnel[t].state = TUNNELOPENING;
2363 if (main_quit != QUIT_SHUTDOWN)
2364 {
2365 controlt *c = controlnew(2); // sending SCCRP
2366 control16(c, 2, version, 1); // protocol version
2367 control32(c, 3, 3, 1); // framing
2368 controls(c, 7, hostname, 1); // host name
2369 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2370 control16(c, 9, t, 1); // assigned tunnel
2371 controladd(c, 0, t); // send the resply
2372 }
2373 else
2374 {
2375 tunnelshutdown(t, "Shutting down", 6, 0, 0);
2376 }
2377 break;
2378 case 2: // SCCRP
2379 tunnel[t].state = TUNNELOPEN;
2380 break;
2381 case 3: // SCCN
2382 tunnel[t].state = TUNNELOPEN;
2383 controlnull(t); // ack
2384 break;
2385 case 4: // StopCCN
2386 controlnull(t); // ack
2387 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2388 break;
2389 case 6: // HELLO
2390 controlnull(t); // simply ACK
2391 break;
2392 case 7: // OCRQ
2393 // TBA
2394 break;
2395 case 8: // OCRO
2396 // TBA
2397 break;
2398 case 9: // OCCN
2399 // TBA
2400 break;
2401 case 10: // ICRQ
2402 if (sessionfree && main_quit != QUIT_SHUTDOWN)
2403 {
2404 controlt *c = controlnew(11); // ICRP
2405
2406 s = sessionfree;
2407 sessionfree = session[s].next;
2408 memset(&session[s], 0, sizeof(session[s]));
2409
2410 if (s > config->cluster_highest_sessionid)
2411 config->cluster_highest_sessionid = s;
2412
2413 session[s].opened = time_now;
2414 session[s].tunnel = t;
2415 session[s].far = asession;
2416 session[s].last_packet = time_now;
2417 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2418 control16(c, 14, s, 1); // assigned session
2419 controladd(c, asession, t); // send the reply
2420
2421 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2422 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2423
2424 session[s].ppp.phase = Establish;
2425 session[s].ppp.lcp = Starting;
2426
2427 STAT(session_created);
2428 break;
2429 }
2430
2431 {
2432 controlt *c = controlnew(14); // CDN
2433 if (!sessionfree)
2434 {
2435 STAT(session_overflow);
2436 LOG(1, 0, t, "No free sessions\n");
2437 control16(c, 1, 4, 0); // temporary lack of resources
2438 }
2439 else
2440 control16(c, 1, 2, 7); // shutting down, try another
2441
2442 controladd(c, asession, t); // send the message
2443 }
2444 return;
2445 case 11: // ICRP
2446 // TBA
2447 break;
2448 case 12: // ICCN
2449 if (amagic == 0) amagic = time_now;
2450 session[s].magic = amagic; // set magic number
2451 session[s].l2tp_flags = aflags; // set flags received
2452 session[s].mru = PPPMTU; // default
2453 controlnull(t); // ack
2454
2455 // start LCP
2456 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2457 sess_local[s].lcp.conf_sent = 1;
2458 sess_local[s].lcp.nak_sent = 0;
2459 sess_local[s].lcp_authtype = config->radius_authprefer;
2460 sess_local[s].ppp_mru = MRU;
2461 session[s].ppp.lcp = RequestSent;
2462 sendlcp(s, t);
2463
2464 break;
2465 case 14: // CDN
2466 controlnull(t); // ack
2467 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2468 break;
2469 case 0xFFFF:
2470 LOG(1, s, t, "Missing message type\n");
2471 break;
2472 default:
2473 STAT(tunnel_rx_errors);
2474 if (mandatory)
2475 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2476 else
2477 LOG(1, s, t, "Unknown message type %d\n", message);
2478 break;
2479 }
2480 if (chapresponse) free(chapresponse);
2481 cluster_send_tunnel(t);
2482 }
2483 else
2484 {
2485 LOG(4, s, t, " Got a ZLB ack\n");
2486 }
2487 }
2488 else
2489 { // data
2490 uint16_t proto;
2491
2492 LOG_HEX(5, "Receive Tunnel Data", p, l);
2493 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2494 { // HDLC address header, discard
2495 p += 2;
2496 l -= 2;
2497 }
2498 if (l < 2)
2499 {
2500 LOG(1, s, t, "Short ppp length %d\n", l);
2501 STAT(tunnel_rx_errors);
2502 return;
2503 }
2504 if (*p & 1)
2505 {
2506 proto = *p++;
2507 l--;
2508 }
2509 else
2510 {
2511 proto = ntohs(*(uint16_t *) p);
2512 p += 2;
2513 l -= 2;
2514 }
2515
2516 if (s && !session[s].opened) // Is something wrong??
2517 {
2518 if (!config->cluster_iam_master)
2519 {
2520 // Pass it off to the master to deal with..
2521 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2522 return;
2523 }
2524
2525
2526 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2527 STAT(tunnel_rx_errors);
2528 return;
2529 }
2530
2531 if (proto == PPPPAP)
2532 {
2533 session[s].last_packet = time_now;
2534 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2535 processpap(s, t, p, l);
2536 }
2537 else if (proto == PPPCHAP)
2538 {
2539 session[s].last_packet = time_now;
2540 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2541 processchap(s, t, p, l);
2542 }
2543 else if (proto == PPPLCP)
2544 {
2545 session[s].last_packet = time_now;
2546 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2547 processlcp(s, t, p, l);
2548 }
2549 else if (proto == PPPIPCP)
2550 {
2551 session[s].last_packet = time_now;
2552 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2553 processipcp(s, t, p, l);
2554 }
2555 else if (proto == PPPIPV6CP && config->ipv6_prefix.s6_addr[0])
2556 {
2557 session[s].last_packet = time_now;
2558 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2559 processipv6cp(s, t, p, l);
2560 }
2561 else if (proto == PPPCCP)
2562 {
2563 session[s].last_packet = time_now;
2564 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2565 processccp(s, t, p, l);
2566 }
2567 else if (proto == PPPIP)
2568 {
2569 if (session[s].die)
2570 {
2571 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2572 return; // closing session, PPP not processed
2573 }
2574
2575 session[s].last_packet = time_now;
2576 if (session[s].walled_garden && !config->cluster_iam_master)
2577 {
2578 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2579 return;
2580 }
2581
2582 processipin(s, t, p, l);
2583 }
2584 else if (proto == PPPIPV6 && config->ipv6_prefix.s6_addr[0])
2585 {
2586 if (session[s].die)
2587 {
2588 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2589 return; // closing session, PPP not processed
2590 }
2591
2592 session[s].last_packet = time_now;
2593 if (session[s].walled_garden && !config->cluster_iam_master)
2594 {
2595 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2596 return;
2597 }
2598
2599 processipv6in(s, t, p, l);
2600 }
2601 else if (session[s].ppp.lcp == Opened)
2602 {
2603 uint8_t buf[MAXETHER];
2604 uint8_t *q;
2605 int mru = session[s].mru;
2606 if (mru > sizeof(buf)) mru = sizeof(buf);
2607
2608 l += 6;
2609 if (l > mru) l = mru;
2610
2611 q = makeppp(buf, sizeof(buf), 0, 0, s, t, proto);
2612 if (!q) return;
2613
2614 *q = CodeRej;
2615 *(q + 1) = ++sess_local[s].lcp_ident;
2616 *(uint16_t *)(q + 2) = l;
2617 *(uint16_t *)(q + 4) = htons(proto);
2618 memcpy(q + 6, p, l - 6);
2619
2620 if (proto == PPPIPV6CP)
2621 LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n");
2622 else
2623 LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto);
2624
2625 tunnelsend(buf, l + (q - buf), t);
2626 }
2627 else
2628 {
2629 LOG(2, s, t, "Unknown PPP protocol 0x%04X received in LCP %s state\n",
2630 proto, ppp_state(session[s].ppp.lcp));
2631 }
2632 }
2633 }
2634
2635 // read and process packet on tun
2636 static void processtun(uint8_t * buf, int len)
2637 {
2638 LOG_HEX(5, "Receive TUN Data", buf, len);
2639 STAT(tun_rx_packets);
2640 INC_STAT(tun_rx_bytes, len);
2641
2642 CSTAT(processtun);
2643
2644 eth_rx_pkt++;
2645 eth_rx += len;
2646 if (len < 22)
2647 {
2648 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2649 STAT(tun_rx_errors);
2650 return;
2651 }
2652
2653 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2654 processipout(buf, len);
2655 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2656 && config->ipv6_prefix.s6_addr[0])
2657 processipv6out(buf, len);
2658
2659 // Else discard.
2660 }
2661
2662 // Handle retries, timeouts. Runs every 1/10th sec, want to ensure
2663 // that we look at the whole of the tunnel, radius and session tables
2664 // every second
2665 static void regular_cleanups(double period)
2666 {
2667 // Next tunnel, radius and session to check for actions on.
2668 static tunnelidt t = 0;
2669 static int r = 0;
2670 static sessionidt s = 0;
2671
2672 int t_actions = 0;
2673 int r_actions = 0;
2674 int s_actions = 0;
2675
2676 int t_slice;
2677 int r_slice;
2678 int s_slice;
2679
2680 int i;
2681 int a;
2682
2683 // divide up tables into slices based on the last run
2684 t_slice = config->cluster_highest_tunnelid * period;
2685 r_slice = (MAXRADIUS - 1) * period;
2686 s_slice = config->cluster_highest_sessionid * period;
2687
2688 if (t_slice < 1)
2689 t_slice = 1;
2690 else if (t_slice > config->cluster_highest_tunnelid)
2691 t_slice = config->cluster_highest_tunnelid;
2692
2693 if (r_slice < 1)
2694 r_slice = 1;
2695 else if (r_slice > (MAXRADIUS - 1))
2696 r_slice = MAXRADIUS - 1;
2697
2698 if (s_slice < 1)
2699 s_slice = 1;
2700 else if (s_slice > config->cluster_highest_sessionid)
2701 s_slice = config->cluster_highest_sessionid;
2702
2703 LOG(4, 0, 0, "Begin regular cleanup (last %f seconds ago)\n", period);
2704
2705 for (i = 0; i < t_slice; i++)
2706 {
2707 t++;
2708 if (t > config->cluster_highest_tunnelid)
2709 t = 1;
2710
2711 // check for expired tunnels
2712 if (tunnel[t].die && tunnel[t].die <= TIME)
2713 {
2714 STAT(tunnel_timeout);
2715 tunnelkill(t, "Expired");
2716 t_actions++;
2717 continue;
2718 }
2719 // check for message resend
2720 if (tunnel[t].retry && tunnel[t].controlc)
2721 {
2722 // resend pending messages as timeout on reply
2723 if (tunnel[t].retry <= TIME)
2724 {
2725 controlt *c = tunnel[t].controls;
2726 uint8_t w = tunnel[t].window;
2727 tunnel[t].try++; // another try
2728 if (tunnel[t].try > 5)
2729 tunnelkill(t, "Timeout on control message"); // game over
2730 else
2731 while (c && w--)
2732 {
2733 tunnelsend(c->buf, c->length, t);
2734 c = c->next;
2735 }
2736
2737 t_actions++;
2738 }
2739 }
2740 // Send hello
2741 if (tunnel[t].state == TUNNELOPEN && (time_now - tunnel[t].lastrec) > 60)
2742 {
2743 controlt *c = controlnew(6); // sending HELLO
2744 controladd(c, 0, t); // send the message
2745 LOG(3, 0, t, "Sending HELLO message\n");
2746 t_actions++;
2747 }
2748
2749 // Check for tunnel changes requested from the CLI
2750 if ((a = cli_tunnel_actions[t].action))
2751 {
2752 cli_tunnel_actions[t].action = 0;
2753 if (a & CLI_TUN_KILL)
2754 {
2755 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2756 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2757 t_actions++;
2758 }
2759 }
2760 }
2761
2762 for (i = 0; i < r_slice; i++)
2763 {
2764 r++;
2765 if (r >= MAXRADIUS)
2766 r = 1;
2767
2768 if (!radius[r].state)
2769 continue;
2770
2771 if (radius[r].retry <= TIME)
2772 {
2773 radiusretry(r);
2774 r_actions++;
2775 }
2776 }
2777
2778 for (i = 0; i < s_slice; i++)
2779 {
2780 s++;
2781 if (s > config->cluster_highest_sessionid)
2782 s = 1;
2783
2784 if (!session[s].opened) // Session isn't in use
2785 continue;
2786
2787 // check for expired sessions
2788 if (session[s].die)
2789 {
2790 if (session[s].die <= TIME)
2791 {
2792 sessionkill(s, "Expired");
2793 s_actions++;
2794 }
2795 continue;
2796 }
2797
2798 // PPP timeouts
2799 if (sess_local[s].lcp.restart <= time_now)
2800 {
2801 int next_state = session[s].ppp.lcp;
2802 switch (session[s].ppp.lcp)
2803 {
2804 case RequestSent:
2805 case AckReceived:
2806 next_state = RequestSent;
2807
2808 case AckSent:
2809 if (sess_local[s].lcp.conf_sent < config->ppp_max_configure)
2810 {
2811 LOG(3, s, session[s].tunnel, "No ACK for LCP ConfigReq... resending\n");
2812 sess_local[s].lcp.restart = time_now + config->ppp_restart_time;
2813 sess_local[s].lcp.conf_sent++;
2814 sendlcp(s, session[s].tunnel);
2815 change_state(s, lcp, next_state);
2816 }
2817 else
2818 {
2819 sessionshutdown(s, "No response to LCP ConfigReq.", 3, 0);
2820 STAT(session_timeout);
2821 }
2822
2823 s_actions++;
2824 }
2825
2826 if (session[s].die)
2827 continue;
2828 }
2829
2830 if (sess_local[s].ipcp.restart <= time_now)
2831 {
2832 int next_state = session[s].ppp.ipcp;
2833 switch (session[s].ppp.ipcp)
2834 {
2835 case RequestSent:
2836 case AckReceived:
2837 next_state = RequestSent;
2838
2839 case AckSent:
2840 if (sess_local[s].ipcp.conf_sent < config->ppp_max_configure)
2841 {
2842 LOG(3, s, session[s].tunnel, "No ACK for IPCP ConfigReq... resending\n");
2843 sess_local[s].ipcp.restart = time_now + config->ppp_restart_time;
2844 sess_local[s].ipcp.conf_sent++;
2845 sendipcp(s, session[s].tunnel);
2846 change_state(s, ipcp, next_state);
2847 }
2848 else
2849 {
2850 sessionshutdown(s, "No response to IPCP ConfigReq.", 3, 0);
2851 STAT(session_timeout);
2852 }
2853
2854 s_actions++;
2855 }
2856
2857 if (session[s].die)
2858 continue;
2859 }
2860
2861 if (sess_local[s].ipv6cp.restart <= time_now)
2862 {
2863 int next_state = session[s].ppp.ipv6cp;
2864 switch (session[s].ppp.ipv6cp)
2865 {
2866 case RequestSent:
2867 case AckReceived:
2868 next_state = RequestSent;
2869
2870 case AckSent:
2871 if (sess_local[s].ipv6cp.conf_sent < config->ppp_max_configure)
2872 {
2873 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq... resending\n");
2874 sess_local[s].ipv6cp.restart = time_now + config->ppp_restart_time;
2875 sess_local[s].ipv6cp.conf_sent++;
2876 sendipv6cp(s, session[s].tunnel);
2877 change_state(s, ipv6cp, next_state);
2878 }
2879 else
2880 {
2881 LOG(3, s, session[s].tunnel, "No ACK for IPV6CP ConfigReq\n");
2882 change_state(s, ipv6cp, Stopped);
2883 }
2884
2885 s_actions++;
2886 }
2887 }
2888
2889 if (sess_local[s].ccp.restart <= time_now)
2890 {
2891 int next_state = session[s].ppp.ccp;
2892 switch (session[s].ppp.ccp)
2893 {
2894 case RequestSent:
2895 case AckReceived:
2896 next_state = RequestSent;
2897
2898 case AckSent:
2899 if (sess_local[s].ccp.conf_sent < config->ppp_max_configure)
2900 {
2901 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq... resending\n");
2902 sess_local[s].ccp.restart = time_now + config->ppp_restart_time;
2903 sess_local[s].ccp.conf_sent++;
2904 sendccp(s, session[s].tunnel);
2905 change_state(s, ccp, next_state);
2906 }
2907 else
2908 {
2909 LOG(3, s, session[s].tunnel, "No ACK for CCP ConfigReq\n");
2910 change_state(s, ccp, Stopped);
2911 }
2912
2913 s_actions++;
2914 }
2915 }
2916
2917 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2918 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2919 {
2920 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2921 STAT(session_timeout);
2922 s_actions++;
2923 continue;
2924 }
2925
2926 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2927 if (session[s].ppp.phase >= Establish && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2928 {
2929 uint8_t b[MAXETHER];
2930
2931 uint8_t *q = makeppp(b, sizeof(b), 0, 0, s, session[s].tunnel, PPPLCP);
2932 if (!q) continue;
2933
2934 *q = EchoReq;
2935 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2936 *(uint16_t *)(q + 2) = htons(8); // Length
2937 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2938
2939 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2940 (int)(time_now - session[s].last_packet));
2941 tunnelsend(b, 24, session[s].tunnel); // send it
2942 s_actions++;
2943 }
2944
2945 // Check for actions requested from the CLI
2946 if ((a = cli_session_actions[s].action))
2947 {
2948 int send = 0;
2949
2950 cli_session_actions[s].action = 0;
2951 if (a & CLI_SESS_KILL)
2952 {
2953 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2954 sessionshutdown(s, "Requested by administrator.", 3, 0);
2955 a = 0; // dead, no need to check for other actions
2956 s_actions++;
2957 }
2958
2959 if (a & CLI_SESS_NOSNOOP)
2960 {
2961 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2962 session[s].snoop_ip = 0;
2963 session[s].snoop_port = 0;
2964 s_actions++;
2965 send++;
2966 }
2967 else if (a & CLI_SESS_SNOOP)
2968 {
2969 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2970 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2971 cli_session_actions[s].snoop_port);
2972
2973 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2974 session[s].snoop_port = cli_session_actions[s].snoop_port;
2975 s_actions++;
2976 send++;
2977 }
2978
2979 if (a & CLI_SESS_NOTHROTTLE)
2980 {
2981 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2982 throttle_session(s, 0, 0);
2983 s_actions++;
2984 send++;
2985 }
2986 else if (a & CLI_SESS_THROTTLE)
2987 {
2988 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2989 cli_session_actions[s].throttle_in,
2990 cli_session_actions[s].throttle_out);
2991
2992 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2993 s_actions++;
2994 send++;
2995 }
2996
2997 if (a & CLI_SESS_NOFILTER)
2998 {
2999 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
3000 filter_session(s, 0, 0);
3001 s_actions++;
3002 send++;
3003 }
3004 else if (a & CLI_SESS_FILTER)
3005 {
3006 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
3007 cli_session_actions[s].filter_in,
3008 cli_session_actions[s].filter_out);
3009
3010 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
3011 s_actions++;
3012 send++;
3013 }
3014
3015 if (send)
3016 cluster_send_session(s);
3017 }
3018
3019 // RADIUS interim accounting
3020 if (config->radius_accounting && config->radius_interim > 0
3021 && session[s].ip && !session[s].walled_garden
3022 && !sess_local[s].radius // RADIUS already in progress
3023 && time_now - sess_local[s].last_interim >= config->radius_interim)
3024 {
3025 int rad = radiusnew(s);
3026 if (!rad)
3027 {
3028 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
3029 STAT(radius_overflow);
3030 continue;
3031 }
3032
3033 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
3034 session[s].user, session[s].unique_id);
3035
3036 radiussend(rad, RADIUSINTERIM);
3037 sess_local[s].last_interim = time_now;
3038 s_actions++;
3039 }
3040 }
3041
3042 LOG(4, 0, 0, "End regular cleanup: checked %d/%d/%d tunnels/radius/sessions; %d/%d/%d actions\n",
3043 t_slice, r_slice, s_slice, t_actions, r_actions, s_actions);
3044 }
3045
3046 //
3047 // Are we in the middle of a tunnel update, or radius
3048 // requests??
3049 //
3050 static int still_busy(void)
3051 {
3052 int i;
3053 static clockt last_talked = 0;
3054 static clockt start_busy_wait = 0;
3055
3056 if (!config->cluster_iam_master)
3057 {
3058 #ifdef BGP
3059 static time_t stopped_bgp = 0;
3060 if (bgp_configured)
3061 {
3062 if (!stopped_bgp)
3063 {
3064 LOG(1, 0, 0, "Shutting down in %d seconds, stopping BGP...\n", QUIT_DELAY);
3065
3066 for (i = 0; i < BGP_NUM_PEERS; i++)
3067 if (bgp_peers[i].state == Established)
3068 bgp_stop(&bgp_peers[i]);
3069
3070 stopped_bgp = time_now;
3071
3072 // we don't want to become master
3073 cluster_send_ping(0);
3074
3075 return 1;
3076 }
3077
3078 if (time_now < (stopped_bgp + QUIT_DELAY))
3079 return 1;
3080 }
3081 #endif /* BGP */
3082
3083 return 0;
3084 }
3085
3086 if (main_quit == QUIT_SHUTDOWN)
3087 {
3088 static int dropped = 0;
3089 if (!dropped)
3090 {
3091 int i;
3092
3093 LOG(1, 0, 0, "Dropping sessions and tunnels\n");
3094 for (i = 1; i < MAXTUNNEL; i++)
3095 if (tunnel[i].ip || tunnel[i].state)
3096 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3097
3098 dropped = 1;
3099 }
3100 }
3101
3102 if (start_busy_wait == 0)
3103 start_busy_wait = TIME;
3104
3105 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
3106 {
3107 if (!tunnel[i].controlc)
3108 continue;
3109
3110 if (last_talked != TIME)
3111 {
3112 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
3113 last_talked = TIME;
3114 }
3115 return 1;
3116 }
3117
3118 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
3119 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
3120 {
3121 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
3122 return 0;
3123 }
3124
3125 for (i = 1; i < MAXRADIUS; i++)
3126 {
3127 if (radius[i].state == RADIUSNULL)
3128 continue;
3129 if (radius[i].state == RADIUSWAIT)
3130 continue;
3131
3132 if (last_talked != TIME)
3133 {
3134 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
3135 last_talked = TIME;
3136 }
3137 return 1;
3138 }
3139
3140 return 0;
3141 }
3142
3143 #ifdef HAVE_EPOLL
3144 # include <sys/epoll.h>
3145 #else
3146 # define FAKE_EPOLL_IMPLEMENTATION /* include the functions */
3147 # include "fake_epoll.h"
3148 #endif
3149
3150 // the base set of fds polled: cli, cluster, tun, udp, control, dae
3151 #define BASE_FDS 6
3152
3153 // additional polled fds
3154 #ifdef BGP
3155 # define EXTRA_FDS BGP_NUM_PEERS
3156 #else
3157 # define EXTRA_FDS 0
3158 #endif
3159
3160 // main loop - gets packets on tun or udp and processes them
3161 static void mainloop(void)
3162 {
3163 int i;
3164 uint8_t buf[65536];
3165 clockt next_cluster_ping = 0; // send initial ping immediately
3166 struct epoll_event events[BASE_FDS + RADIUS_FDS + EXTRA_FDS];
3167 int maxevent = sizeof(events)/sizeof(*events);
3168
3169 if ((epollfd = epoll_create(maxevent)) < 0)
3170 {
3171 LOG(0, 0, 0, "epoll_create failed: %s\n", strerror(errno));
3172 exit(1);
3173 }
3174
3175 LOG(4, 0, 0, "Beginning of main loop. clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
3176 clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
3177
3178 /* setup our fds to poll for input */
3179 {
3180 static struct event_data d[BASE_FDS];
3181 struct epoll_event e;
3182
3183 e.events = EPOLLIN;
3184 i = 0;
3185
3186 d[i].type = FD_TYPE_CLI;
3187 e.data.ptr = &d[i++];
3188 epoll_ctl(epollfd, EPOLL_CTL_ADD, clifd, &e);
3189
3190 d[i].type = FD_TYPE_CLUSTER;
3191 e.data.ptr = &d[i++];
3192 epoll_ctl(epollfd, EPOLL_CTL_ADD, cluster_sockfd, &e);
3193
3194 d[i].type = FD_TYPE_TUN;
3195 e.data.ptr = &d[i++];
3196 epoll_ctl(epollfd, EPOLL_CTL_ADD, tunfd, &e);
3197
3198 d[i].type = FD_TYPE_UDP;
3199 e.data.ptr = &d[i++];
3200 epoll_ctl(epollfd, EPOLL_CTL_ADD, udpfd, &e);
3201
3202 d[i].type = FD_TYPE_CONTROL;
3203 e.data.ptr = &d[i++];
3204 epoll_ctl(epollfd, EPOLL_CTL_ADD, controlfd, &e);
3205
3206 d[i].type = FD_TYPE_DAE;
3207 e.data.ptr = &d[i++];
3208 epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
3209 }
3210
3211 #ifdef BGP
3212 signal(SIGPIPE, SIG_IGN);
3213 bgp_setup(config->as_number);
3214 if (config->bind_address)
3215 bgp_add_route(config->bind_address, 0xffffffff);
3216
3217 for (i = 0; i < BGP_NUM_PEERS; i++)
3218 {
3219 if (config->neighbour[i].name[0])
3220 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3221 config->neighbour[i].as, config->neighbour[i].keepalive,
3222 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3223 }
3224 #endif /* BGP */
3225
3226 while (!main_quit || still_busy())
3227 {
3228 int more = 0;
3229 int n;
3230
3231 if (config->reload_config)
3232 {
3233 // Update the config state based on config settings
3234 update_config();
3235 }
3236
3237 #ifdef BGP
3238 bgp_set_poll();
3239 #endif /* BGP */
3240
3241 n = epoll_wait(epollfd, events, maxevent, 100); // timeout 100ms (1/10th sec)
3242 STAT(select_called);
3243
3244 TIME = now(NULL);
3245 if (n < 0)
3246 {
3247 if (errno == EINTR ||
3248 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
3249 continue;
3250
3251 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
3252 break; // exit
3253 }
3254
3255 if (n)
3256 {
3257 struct sockaddr_in addr;
3258 socklen_t alen;
3259 int c, s;
3260 int udp_ready = 0;
3261 int tun_ready = 0;
3262 int cluster_ready = 0;
3263 int udp_pkts = 0;
3264 int tun_pkts = 0;
3265 int cluster_pkts = 0;
3266 #ifdef BGP
3267 uint32_t bgp_events[BGP_NUM_PEERS];
3268 memset(bgp_events, 0, sizeof(bgp_events));
3269 #endif /* BGP */
3270
3271 for (c = n, i = 0; i < c; i++)
3272 {
3273 struct event_data *d = events[i].data.ptr;
3274 switch (d->type)
3275 {
3276 case FD_TYPE_CLI: // CLI connections
3277 {
3278 int cli;
3279
3280 alen = sizeof(addr);
3281 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
3282 {
3283 cli_do(cli);
3284 close(cli);
3285 }
3286 else
3287 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
3288
3289 n--;
3290 break;
3291 }
3292
3293 // these are handled below, with multiple interleaved reads
3294 case FD_TYPE_CLUSTER: cluster_ready++; break;
3295 case FD_TYPE_TUN: tun_ready++; break;
3296 case FD_TYPE_UDP: udp_ready++; break;
3297
3298 case FD_TYPE_CONTROL: // nsctl commands
3299 alen = sizeof(addr);
3300 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3301 n--;
3302 break;
3303
3304 case FD_TYPE_DAE: // DAE requests
3305 alen = sizeof(addr);
3306 processdae(buf, recvfrom(daefd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
3307 n--;
3308 break;
3309
3310 case FD_TYPE_RADIUS: // RADIUS response
3311 s = recv(radfds[d->index], buf, sizeof(buf), 0);
3312 if (s >= 0 && config->cluster_iam_master)
3313 processrad(buf, s, d->index);
3314
3315 n--;
3316 break;
3317
3318 #ifdef BGP
3319 case FD_TYPE_BGP:
3320 bgp_events[d->index] = events[i].events;
3321 n--;
3322 break;
3323 #endif /* BGP */
3324
3325 default:
3326 LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
3327 }
3328 }
3329
3330 #ifdef BGP
3331 bgp_process(bgp_events);
3332 #endif /* BGP */
3333
3334 for (c = 0; n && c < config->multi_read_count; c++)
3335 {
3336 // L2TP
3337 if (udp_ready)
3338 {
3339 alen = sizeof(addr);
3340 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3341 {
3342 processudp(buf, s, &addr);
3343 udp_pkts++;
3344 }
3345 else
3346 {
3347 udp_ready = 0;
3348 n--;
3349 }
3350 }
3351
3352 // incoming IP
3353 if (tun_ready)
3354 {
3355 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3356 {
3357 processtun(buf, s);
3358 tun_pkts++;
3359 }
3360 else
3361 {
3362 tun_ready = 0;
3363 n--;
3364 }
3365 }
3366
3367 // cluster
3368 if (cluster_ready)
3369 {
3370 alen = sizeof(addr);
3371 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3372 {
3373 processcluster(buf, s, addr.sin_addr.s_addr);
3374 cluster_pkts++;
3375 }
3376 else
3377 {
3378 cluster_ready = 0;
3379 n--;
3380 }
3381 }
3382 }
3383
3384 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3385 STAT(multi_read_used);
3386
3387 if (c >= config->multi_read_count)
3388 {
3389 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3390 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3391
3392 STAT(multi_read_exceeded);
3393 more++;
3394 }
3395 }
3396
3397 // Runs on every machine (master and slaves).
3398 if (next_cluster_ping <= TIME)
3399 {
3400 // Check to see which of the cluster is still alive..
3401
3402 cluster_send_ping(basetime); // Only does anything if we're a slave
3403 cluster_check_master(); // ditto.
3404
3405 cluster_heartbeat(); // Only does anything if we're a master.
3406 cluster_check_slaves(); // ditto.
3407
3408 master_update_counts(); // If we're a slave, send our byte counters to our master.
3409
3410 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3411 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3412 else
3413 next_cluster_ping = TIME + config->cluster_hb_interval;
3414 }
3415
3416 if (!config->cluster_iam_master)
3417 continue;
3418
3419 // Run token bucket filtering queue..
3420 // Only run it every 1/10th of a second.
3421 {
3422 static clockt last_run = 0;
3423 if (last_run != TIME)
3424 {
3425 last_run = TIME;
3426 tbf_run_timer();
3427 }
3428 }
3429
3430 // Handle timeouts, retries etc.
3431 {
3432 static double last_clean = 0;
3433 double this_clean;
3434 double diff;
3435
3436 TIME = now(&this_clean);
3437 diff = this_clean - last_clean;
3438
3439 // Run during idle time (after we've handled
3440 // all incoming packets) or every 1/10th sec
3441 if (!more || diff > 0.1)
3442 {
3443 regular_cleanups(diff);
3444 last_clean = this_clean;
3445 }
3446 }
3447
3448 if (*config->accounting_dir)
3449 {
3450 static clockt next_acct = 0;
3451 static clockt next_shut_acct = 0;
3452
3453 if (next_acct <= TIME)
3454 {
3455 // Dump accounting data
3456 next_acct = TIME + ACCT_TIME;
3457 next_shut_acct = TIME + ACCT_SHUT_TIME;
3458 dump_acct_info(1);
3459 }
3460 else if (next_shut_acct <= TIME)
3461 {
3462 // Dump accounting data for shutdown sessions
3463 next_shut_acct = TIME + ACCT_SHUT_TIME;
3464 if (shut_acct_n)
3465 dump_acct_info(0);
3466 }
3467 }
3468 }
3469
3470 // Are we the master and shutting down??
3471 if (config->cluster_iam_master)
3472 cluster_heartbeat(); // Flush any queued changes..
3473
3474 // Ok. Notify everyone we're shutting down. If we're
3475 // the master, this will force an election.
3476 cluster_send_ping(0);
3477
3478 //
3479 // Important!!! We MUST not process any packets past this point!
3480 LOG(1, 0, 0, "Shutdown complete\n");
3481 }
3482
3483 static void stripdomain(char *host)
3484 {
3485 char *p;
3486
3487 if ((p = strchr(host, '.')))
3488 {
3489 char *domain = 0;
3490 char _domain[1024];
3491
3492 // strip off domain
3493 FILE *resolv = fopen("/etc/resolv.conf", "r");
3494 if (resolv)
3495 {
3496 char buf[1024];
3497 char *b;
3498
3499 while (fgets(buf, sizeof(buf), resolv))
3500 {
3501 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3502 continue;
3503
3504 if (!isspace(buf[6]))
3505 continue;
3506
3507 b = buf + 7;
3508 while (isspace(*b)) b++;
3509
3510 if (*b)
3511 {
3512 char *d = b;
3513 while (*b && !isspace(*b)) b++;
3514 *b = 0;
3515 if (buf[0] == 'd') // domain is canonical
3516 {
3517 domain = d;
3518 break;
3519 }
3520
3521 // first search line
3522 if (!domain)
3523 {
3524 // hold, may be subsequent domain line
3525 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3526 domain = _domain;
3527 }
3528 }
3529 }
3530
3531 fclose(resolv);
3532 }
3533
3534 if (domain)
3535 {
3536 int hl = strlen(host);
3537 int dl = strlen(domain);
3538 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3539 host[hl -dl - 1] = 0;
3540 }
3541 else
3542 {
3543 *p = 0; // everything after first dot
3544 }
3545 }
3546 }
3547
3548 // Init data structures
3549 static void initdata(int optdebug, char *optconfig)
3550 {
3551 int i;
3552
3553 if (!(config = shared_malloc(sizeof(configt))))
3554 {
3555 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3556 exit(1);
3557 }
3558
3559 memset(config, 0, sizeof(configt));
3560 time(&config->start_time);
3561 strncpy(config->config_file, optconfig, strlen(optconfig));
3562 config->debug = optdebug;
3563 config->num_tbfs = MAXTBFS;
3564 config->rl_rate = 28; // 28kbps
3565 config->cluster_mcast_ttl = 1;
3566 config->cluster_master_min_adv = 1;
3567 config->ppp_restart_time = 3;
3568 config->ppp_max_configure = 10;
3569 config->ppp_max_failure = 5;
3570 strcpy(config->random_device, RANDOMDEVICE);
3571
3572 log_stream = stderr;
3573
3574 #ifdef RINGBUFFER
3575 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3576 {
3577 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3578 exit(1);
3579 }
3580 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3581 #endif
3582
3583 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3584 {
3585 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3586 exit(1);
3587 }
3588 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3589 {
3590 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3591 exit(1);
3592 }
3593 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3594 {
3595 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3596 exit(1);
3597 }
3598
3599 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3600 {
3601 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3602 exit(1);
3603 }
3604
3605 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3606 {
3607 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3608 exit(1);
3609 }
3610
3611 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3612 {
3613 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3614 exit(1);
3615 }
3616
3617 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3618 {
3619 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3620 exit(1);
3621 }
3622 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3623
3624 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3625 {
3626 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3627 exit(1);
3628 }
3629 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3630
3631 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3632 {
3633 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3634 exit(1);
3635 }
3636 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3637
3638 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3639 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3640 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3641 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3642
3643 // Put all the sessions on the free list marked as undefined.
3644 for (i = 1; i < MAXSESSION; i++)
3645 {
3646 session[i].next = i + 1;
3647 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3648 }
3649 session[MAXSESSION - 1].next = 0;
3650 sessionfree = 1;
3651
3652 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3653 for (i = 1; i < MAXTUNNEL; i++)
3654 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3655
3656 if (!*hostname)
3657 {
3658 // Grab my hostname unless it's been specified
3659 gethostname(hostname, sizeof(hostname));
3660 stripdomain(hostname);
3661 }
3662
3663 _statistics->start_time = _statistics->last_reset = time(NULL);
3664
3665 #ifdef BGP
3666 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3667 {
3668 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3669 exit(1);
3670 }
3671 #endif /* BGP */
3672 }
3673
3674 static int assign_ip_address(sessionidt s)
3675 {
3676 uint32_t i;
3677 int best = -1;
3678 time_t best_time = time_now;
3679 char *u = session[s].user;
3680 char reuse = 0;
3681
3682
3683 CSTAT(assign_ip_address);
3684
3685 for (i = 1; i < ip_pool_size; i++)
3686 {
3687 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3688 continue;
3689
3690 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3691 {
3692 best = i;
3693 reuse = 1;
3694 break;
3695 }
3696
3697 if (ip_address_pool[i].last < best_time)
3698 {
3699 best = i;
3700 if (!(best_time = ip_address_pool[i].last))
3701 break; // never used, grab this one
3702 }
3703 }
3704
3705 if (best < 0)
3706 {
3707 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3708 return 0;
3709 }
3710
3711 session[s].ip = ip_address_pool[best].address;
3712 session[s].ip_pool_index = best;
3713 ip_address_pool[best].assigned = 1;
3714 ip_address_pool[best].last = time_now;
3715 ip_address_pool[best].session = s;
3716 if (session[s].walled_garden)
3717 /* Don't track addresses of users in walled garden (note: this
3718 means that their address isn't "sticky" even if they get
3719 un-gardened). */
3720 ip_address_pool[best].user[0] = 0;
3721 else
3722 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3723
3724 STAT(ip_allocated);
3725 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3726 reuse ? "Reusing" : "Allocating", best);
3727
3728 return 1;
3729 }
3730
3731 static void free_ip_address(sessionidt s)
3732 {
3733 int i = session[s].ip_pool_index;
3734
3735
3736 CSTAT(free_ip_address);
3737
3738 if (!session[s].ip)
3739 return; // what the?
3740
3741 if (i < 0) // Is this actually part of the ip pool?
3742 i = 0;
3743
3744 STAT(ip_freed);
3745 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3746 session[s].ip = 0;
3747 ip_address_pool[i].assigned = 0;
3748 ip_address_pool[i].session = 0;
3749 ip_address_pool[i].last = time_now;
3750 }
3751
3752 //
3753 // Fsck the address pool against the session table.
3754 // Normally only called when we become a master.
3755 //
3756 // This isn't perfect: We aren't keep tracking of which
3757 // users used to have an IP address.
3758 //
3759 void rebuild_address_pool(void)
3760 {
3761 int i;
3762
3763 //
3764 // Zero the IP pool allocation, and build
3765 // a map from IP address to pool index.
3766 for (i = 1; i < MAXIPPOOL; ++i)
3767 {
3768 ip_address_pool[i].assigned = 0;
3769 ip_address_pool[i].session = 0;
3770 if (!ip_address_pool[i].address)
3771 continue;
3772
3773 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3774 }
3775
3776 for (i = 0; i < MAXSESSION; ++i)
3777 {
3778 int ipid;
3779 if (!(session[i].opened && session[i].ip))
3780 continue;
3781
3782 ipid = - lookup_ipmap(htonl(session[i].ip));
3783
3784 if (session[i].ip_pool_index < 0)
3785 {
3786 // Not allocated out of the pool.
3787 if (ipid < 1) // Not found in the pool either? good.
3788 continue;
3789
3790 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3791 i, fmtaddr(session[i].ip, 0), ipid);
3792
3793 // Fall through and process it as part of the pool.
3794 }
3795
3796
3797 if (ipid > MAXIPPOOL || ipid < 0)
3798 {
3799 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3800 ipid = -1;
3801 session[i].ip_pool_index = ipid;
3802 continue;
3803 }
3804
3805 ip_address_pool[ipid].assigned = 1;
3806 ip_address_pool[ipid].session = i;
3807 ip_address_pool[ipid].last = time_now;
3808 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3809 session[i].ip_pool_index = ipid;
3810 cache_ipmap(session[i].ip, i); // Fix the ip map.
3811 }
3812 }
3813
3814 //
3815 // Fix the address pool to match a changed session.
3816 // (usually when the master sends us an update).
3817 static void fix_address_pool(int sid)
3818 {
3819 int ipid;
3820
3821 ipid = session[sid].ip_pool_index;
3822
3823 if (ipid > ip_pool_size)
3824 return; // Ignore it. rebuild_address_pool will fix it up.
3825
3826 if (ip_address_pool[ipid].address != session[sid].ip)
3827 return; // Just ignore it. rebuild_address_pool will take care of it.
3828
3829 ip_address_pool[ipid].assigned = 1;
3830 ip_address_pool[ipid].session = sid;
3831 ip_address_pool[ipid].last = time_now;
3832 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3833 }
3834
3835 //
3836 // Add a block of addresses to the IP pool to hand out.
3837 //
3838 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3839 {
3840 int i;
3841 if (mask == 0)
3842 mask = 0xffffffff; // Host route only.
3843
3844 addr &= mask;
3845
3846 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3847 return ;
3848
3849 for (i = addr ;(i & mask) == addr; ++i)
3850 {
3851 if ((i & 0xff) == 0 || (i&0xff) == 255)
3852 continue; // Skip 0 and broadcast addresses.
3853
3854 ip_address_pool[ip_pool_size].address = i;
3855 ip_address_pool[ip_pool_size].assigned = 0;
3856 ++ip_pool_size;
3857 if (ip_pool_size >= MAXIPPOOL)
3858 {
3859 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3860 return;
3861 }
3862 }
3863 }
3864
3865 // Initialize the IP address pool
3866 static void initippool()
3867 {
3868 FILE *f;
3869 char *p;
3870 char buf[4096];
3871 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3872
3873 if (!(f = fopen(IPPOOLFILE, "r")))
3874 {
3875 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3876 exit(1);
3877 }
3878
3879 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3880 {
3881 char *pool = buf;
3882 buf[4095] = 0; // Force it to be zero terminated/
3883
3884 if (*buf == '#' || *buf == '\n')
3885 continue; // Skip comments / blank lines
3886 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3887 if ((p = (char *)strchr(buf, ':')))
3888 {
3889 in_addr_t src;
3890 *p = '\0';
3891 src = inet_addr(buf);
3892 if (src == INADDR_NONE)
3893 {
3894 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3895 exit(1);
3896 }
3897 // This entry is for a specific IP only
3898 if (src != config->bind_address)
3899 continue;
3900 *p = ':';
3901 pool = p+1;
3902 }
3903 if ((p = (char *)strchr(pool, '/')))
3904 {
3905 // It's a range
3906 int numbits = 0;
3907 in_addr_t start = 0, mask = 0;
3908
3909 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3910 *p++ = 0;
3911 if (!*p || !(numbits = atoi(p)))
3912 {
3913 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3914 continue;
3915 }
3916 start = ntohl(inet_addr(pool));
3917 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3918
3919 // Add a static route for this pool
3920 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3921 fmtaddr(htonl(start), 0), 32 + mask);
3922
3923 routeset(0, start, mask, 0, 1);
3924
3925 add_to_ip_pool(start, mask);
3926 }
3927 else
3928 {
3929 // It's a single ip address
3930 add_to_ip_pool(inet_addr(pool), 0);
3931 }
3932 }
3933 fclose(f);
3934 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3935 }
3936
3937 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port)
3938 {
3939 struct sockaddr_in snoop_addr = {0};
3940 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3941 return;
3942
3943 snoop_addr.sin_family = AF_INET;
3944 snoop_addr.sin_addr.s_addr = destination;
3945 snoop_addr.sin_port = ntohs(port);
3946
3947 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3948 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3949 htons(snoop_addr.sin_port));
3950
3951 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3952 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3953
3954 STAT(packets_snooped);
3955 }
3956
3957 static int dump_session(FILE **f, sessiont *s)
3958 {
3959 if (!s->opened || !s->ip || !(s->cin_delta || s->cout_delta) || !*s->user || s->walled_garden)
3960 return 1;
3961
3962 if (!*f)
3963 {
3964 char filename[1024];
3965 char timestr[64];
3966 time_t now = time(NULL);
3967
3968 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3969 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3970
3971 if (!(*f = fopen(filename, "w")))
3972 {
3973 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3974 return 0;
3975 }
3976
3977 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3978 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3979 "# host: %s\n"
3980 "# endpoint: %s\n"
3981 "# time: %ld\n"
3982 "# uptime: %ld\n"
3983 "# format: username ip qos uptxoctets downrxoctets\n",
3984 hostname,
3985 fmtaddr(config->bind_address ? config->bind_address : my_address, 0),
3986 now,
3987 now - basetime);
3988 }
3989
3990 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3991 fprintf(*f, "%s %s %d %u %u\n",
3992 s->user, // username
3993 fmtaddr(htonl(s->ip), 0), // ip
3994 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3995 (uint32_t) s->cin_delta, // uptxoctets
3996 (uint32_t) s->cout_delta); // downrxoctets
3997
3998 s->cin_delta = s->cout_delta = 0;
3999
4000 return 1;
4001 }
4002
4003 static void dump_acct_info(int all)
4004 {
4005 int i;
4006 FILE *f = NULL;
4007
4008
4009 CSTAT(dump_acct_info);
4010
4011 if (shut_acct_n)
4012 {
4013 for (i = 0; i < shut_acct_n; i++)
4014 dump_session(&f, &shut_acct[i]);
4015
4016 shut_acct_n = 0;
4017 }
4018
4019 if (all)
4020 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4021 dump_session(&f, &session[i]);
4022
4023 if (f)
4024 fclose(f);
4025 }
4026
4027 // Main program
4028 int main(int argc, char *argv[])
4029 {
4030 int i;
4031 int optdebug = 0;
4032 char *optconfig = CONFIGFILE;
4033
4034 time(&basetime); // start clock
4035
4036 // scan args
4037 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
4038 {
4039 switch (i)
4040 {
4041 case 'd':
4042 if (fork()) exit(0);
4043 setsid();
4044 freopen("/dev/null", "r", stdin);
4045 freopen("/dev/null", "w", stdout);
4046 freopen("/dev/null", "w", stderr);
4047 break;
4048 case 'v':
4049 optdebug++;
4050 break;
4051 case 'c':
4052 optconfig = optarg;
4053 break;
4054 case 'h':
4055 snprintf(hostname, sizeof(hostname), "%s", optarg);
4056 break;
4057 default:
4058 printf("Args are:\n"
4059 "\t-d\t\tDetach from terminal\n"
4060 "\t-c <file>\tConfig file\n"
4061 "\t-h <hostname>\tForce hostname\n"
4062 "\t-v\t\tDebug\n");
4063
4064 return (0);
4065 break;
4066 }
4067 }
4068
4069 // Start the timer routine off
4070 time(&time_now);
4071 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4072 signal(SIGALRM, sigalrm_handler);
4073 siginterrupt(SIGALRM, 0);
4074
4075 initplugins();
4076 initdata(optdebug, optconfig);
4077
4078 init_cli(hostname);
4079 read_config_file();
4080 init_tbf(config->num_tbfs);
4081
4082 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
4083 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
4084 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
4085 {
4086 struct rlimit rlim;
4087 rlim.rlim_cur = RLIM_INFINITY;
4088 rlim.rlim_max = RLIM_INFINITY;
4089 // Remove the maximum core size
4090 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
4091 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
4092
4093 // Make core dumps go to /tmp
4094 chdir("/tmp");
4095 }
4096
4097 if (config->scheduler_fifo)
4098 {
4099 int ret;
4100 struct sched_param params = {0};
4101 params.sched_priority = 1;
4102
4103 if (get_nprocs() < 2)
4104 {
4105 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
4106 config->scheduler_fifo = 0;
4107 }
4108 else
4109 {
4110 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
4111 {
4112 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
4113 }
4114 else
4115 {
4116 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
4117 config->scheduler_fifo = 0;
4118 }
4119 }
4120 }
4121
4122 /* Set up the cluster communications port. */
4123 if (cluster_init() < 0)
4124 exit(1);
4125
4126 inittun();
4127 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
4128
4129 initudp();
4130 initrad();
4131 initippool();
4132
4133 // seed prng
4134 {
4135 unsigned seed = time_now ^ getpid();
4136 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
4137 srand(seed);
4138 }
4139
4140 signal(SIGHUP, sighup_handler);
4141 signal(SIGCHLD, sigchild_handler);
4142 signal(SIGTERM, shutdown_handler);
4143 signal(SIGINT, shutdown_handler);
4144 signal(SIGQUIT, shutdown_handler);
4145
4146 // Prevent us from getting paged out
4147 if (config->lock_pages)
4148 {
4149 if (!mlockall(MCL_CURRENT))
4150 LOG(1, 0, 0, "Locking pages into memory\n");
4151 else
4152 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
4153 }
4154
4155 alarm(1);
4156
4157 // Drop privileges here
4158 if (config->target_uid > 0 && geteuid() == 0)
4159 setuid(config->target_uid);
4160
4161 mainloop();
4162
4163 /* remove plugins (so cleanup code gets run) */
4164 plugins_done();
4165
4166 // Remove the PID file if we wrote it
4167 if (config->wrote_pid && *config->pid_file == '/')
4168 unlink(config->pid_file);
4169
4170 /* kill CLI children */
4171 signal(SIGTERM, SIG_IGN);
4172 kill(0, SIGTERM);
4173 return 0;
4174 }
4175
4176 static void sighup_handler(int sig)
4177 {
4178 if (log_stream)
4179 {
4180 if (log_stream != stderr)
4181 fclose(log_stream);
4182
4183 log_stream = NULL;
4184 }
4185
4186 read_config_file();
4187 }
4188
4189 static void sigalrm_handler(int sig)
4190 {
4191 // Log current traffic stats
4192
4193 snprintf(config->bandwidth, sizeof(config->bandwidth),
4194 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
4195 (udp_rx / 1024.0 / 1024.0 * 8),
4196 (eth_tx / 1024.0 / 1024.0 * 8),
4197 (eth_rx / 1024.0 / 1024.0 * 8),
4198 (udp_tx / 1024.0 / 1024.0 * 8),
4199 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
4200 udp_rx_pkt, eth_rx_pkt);
4201
4202 udp_tx = udp_rx = 0;
4203 udp_rx_pkt = eth_rx_pkt = 0;
4204 eth_tx = eth_rx = 0;
4205
4206 if (config->dump_speed)
4207 printf("%s\n", config->bandwidth);
4208
4209 // Update the internal time counter
4210 time(&time_now);
4211 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
4212 alarm(1);
4213
4214 {
4215 // Run timer hooks
4216 struct param_timer p = { time_now };
4217 run_plugins(PLUGIN_TIMER, &p);
4218 }
4219
4220 }
4221
4222 static void shutdown_handler(int sig)
4223 {
4224 LOG(1, 0, 0, "Shutting down\n");
4225 main_quit = (sig == SIGQUIT) ? QUIT_SHUTDOWN : QUIT_FAILOVER;
4226 }
4227
4228 static void sigchild_handler(int sig)
4229 {
4230 while (waitpid(-1, NULL, WNOHANG) > 0)
4231 ;
4232 }
4233
4234 static void build_chap_response(uint8_t *challenge, uint8_t id, uint16_t challenge_length, uint8_t **challenge_response)
4235 {
4236 MD5_CTX ctx;
4237 *challenge_response = NULL;
4238
4239 if (!*config->l2tp_secret)
4240 {
4241 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
4242 return;
4243 }
4244
4245 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
4246
4247 *challenge_response = calloc(17, 1);
4248
4249 MD5_Init(&ctx);
4250 MD5_Update(&ctx, &id, 1);
4251 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
4252 MD5_Update(&ctx, challenge, challenge_length);
4253 MD5_Final(*challenge_response, &ctx);
4254
4255 return;
4256 }
4257
4258 static int facility_value(char *name)
4259 {
4260 int i;
4261 for (i = 0; facilitynames[i].c_name; i++)
4262 {
4263 if (strcmp(facilitynames[i].c_name, name) == 0)
4264 return facilitynames[i].c_val;
4265 }
4266 return 0;
4267 }
4268
4269 static void update_config()
4270 {
4271 int i;
4272 char *p;
4273 static int timeout = 0;
4274 static int interval = 0;
4275
4276 // Update logging
4277 closelog();
4278 syslog_log = 0;
4279 if (log_stream)
4280 {
4281 if (log_stream != stderr)
4282 fclose(log_stream);
4283
4284 log_stream = NULL;
4285 }
4286
4287 if (*config->log_filename)
4288 {
4289 if (strstr(config->log_filename, "syslog:") == config->log_filename)
4290 {
4291 char *p = config->log_filename + 7;
4292 if (*p)
4293 {
4294 openlog("l2tpns", LOG_PID, facility_value(p));
4295 syslog_log = 1;
4296 }
4297 }
4298 else if (strchr(config->log_filename, '/') == config->log_filename)
4299 {
4300 if ((log_stream = fopen((char *)(config->log_filename), "a")))
4301 {
4302 fseek(log_stream, 0, SEEK_END);
4303 setbuf(log_stream, NULL);
4304 }
4305 else
4306 {
4307 log_stream = stderr;
4308 setbuf(log_stream, NULL);
4309 }
4310 }
4311 }
4312 else
4313 {
4314 log_stream = stderr;
4315 setbuf(log_stream, NULL);
4316 }
4317
4318 #define L2TP_HDRS (20+8+6+4) // L2TP data encaptulation: ip + udp + l2tp (data) + ppp (inc hdlc)
4319 #define TCP_HDRS (20+20) // TCP encapsulation: ip + tcp
4320
4321 if (config->l2tp_mtu <= 0) config->l2tp_mtu = PPPMTU;
4322 else if (config->l2tp_mtu < MINMTU) config->l2tp_mtu = MINMTU;
4323 else if (config->l2tp_mtu > MAXMTU) config->l2tp_mtu = MAXMTU;
4324
4325 // reset MRU/MSS globals
4326 MRU = config->l2tp_mtu - L2TP_HDRS;
4327 MSS = MRU - TCP_HDRS;
4328
4329 // Update radius
4330 config->numradiusservers = 0;
4331 for (i = 0; i < MAXRADSERVER; i++)
4332 if (config->radiusserver[i])
4333 {
4334 config->numradiusservers++;
4335 // Set radius port: if not set, take the port from the
4336 // first radius server. For the first radius server,
4337 // take the #defined default value from l2tpns.h
4338
4339 // test twice, In case someone works with
4340 // a secondary radius server without defining
4341 // a primary one, this will work even then.
4342 if (i > 0 && !config->radiusport[i])
4343 config->radiusport[i] = config->radiusport[i-1];
4344 if (!config->radiusport[i])
4345 config->radiusport[i] = RADPORT;
4346 }
4347
4348 if (!config->numradiusservers)
4349 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4350
4351 // parse radius_authtypes_s
4352 config->radius_authtypes = config->radius_authprefer = 0;
4353 p = config->radius_authtypes_s;
4354 while (p && *p)
4355 {
4356 char *s = strpbrk(p, " \t,");
4357 int type = 0;
4358
4359 if (s)
4360 {
4361 *s++ = 0;
4362 while (*s == ' ' || *s == '\t')
4363 s++;
4364
4365 if (!*s)
4366 s = 0;
4367 }
4368
4369 if (!strncasecmp("chap", p, strlen(p)))
4370 type = AUTHCHAP;
4371 else if (!strncasecmp("pap", p, strlen(p)))
4372 type = AUTHPAP;
4373 else
4374 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4375
4376 config->radius_authtypes |= type;
4377 if (!config->radius_authprefer)
4378 config->radius_authprefer = type;
4379
4380 p = s;
4381 }
4382
4383 if (!config->radius_authtypes)
4384 {
4385 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4386 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4387 }
4388
4389 // normalise radius_authtypes_s
4390 if (config->radius_authprefer == AUTHPAP)
4391 {
4392 strcpy(config->radius_authtypes_s, "pap");
4393 if (config->radius_authtypes & AUTHCHAP)
4394 strcat(config->radius_authtypes_s, ", chap");
4395 }
4396 else
4397 {
4398 strcpy(config->radius_authtypes_s, "chap");
4399 if (config->radius_authtypes & AUTHPAP)
4400 strcat(config->radius_authtypes_s, ", pap");
4401 }
4402
4403 if (!config->radius_dae_port)
4404 config->radius_dae_port = DAEPORT;
4405
4406 // re-initialise the random number source
4407 initrandom(config->random_device);
4408
4409 // Update plugins
4410 for (i = 0; i < MAXPLUGINS; i++)
4411 {
4412 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4413 continue;
4414
4415 if (*config->plugins[i])
4416 {
4417 // Plugin added
4418 add_plugin(config->plugins[i]);
4419 }
4420 else if (*config->old_plugins[i])
4421 {
4422 // Plugin removed
4423 remove_plugin(config->old_plugins[i]);
4424 }
4425 }
4426
4427 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4428 if (!config->multi_read_count) config->multi_read_count = 10;
4429 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4430 if (!*config->cluster_interface)
4431 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4432
4433 if (!config->cluster_hb_interval)
4434 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4435
4436 if (!config->cluster_hb_timeout)
4437 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4438
4439 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4440 {
4441 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4442 // late, ensure we're sufficiently larger than that
4443 int t = 4 * config->cluster_hb_interval + 11;
4444
4445 if (config->cluster_hb_timeout < t)
4446 {
4447 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4448 config->cluster_hb_timeout = t;
4449 }
4450
4451 // Push timing changes to the slaves immediately if we're the master
4452 if (config->cluster_iam_master)
4453 cluster_heartbeat();
4454
4455 interval = config->cluster_hb_interval;
4456 timeout = config->cluster_hb_timeout;
4457 }
4458
4459 // Write PID file
4460 if (*config->pid_file == '/' && !config->wrote_pid)
4461 {
4462 FILE *f;
4463 if ((f = fopen(config->pid_file, "w")))
4464 {
4465 fprintf(f, "%d\n", getpid());
4466 fclose(f);
4467 config->wrote_pid = 1;
4468 }
4469 else
4470 {
4471 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4472 }
4473 }
4474
4475 config->reload_config = 0;
4476 }
4477
4478 static void read_config_file()
4479 {
4480 FILE *f;
4481
4482 if (!config->config_file) return;
4483 if (!(f = fopen(config->config_file, "r")))
4484 {
4485 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4486 return;
4487 }
4488
4489 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4490 cli_do_file(f);
4491 LOG(3, 0, 0, "Done reading config file\n");
4492 fclose(f);
4493 update_config();
4494 }
4495
4496 int sessionsetup(sessionidt s, tunnelidt t)
4497 {
4498 // A session now exists, set it up
4499 in_addr_t ip;
4500 char *user;
4501 sessionidt i;
4502 int r;
4503
4504 CSTAT(sessionsetup);
4505
4506 LOG(3, s, t, "Doing session setup for session\n");
4507
4508 if (!session[s].ip)
4509 {
4510 assign_ip_address(s);
4511 if (!session[s].ip)
4512 {
4513 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4514 sessionshutdown(s, "No IP addresses available.", 2, 7); // try another
4515 return 0;
4516 }
4517 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4518 fmtaddr(htonl(session[s].ip), 0));
4519 }
4520
4521
4522 // Make sure this is right
4523 session[s].tunnel = t;
4524
4525 // zap old sessions with same IP and/or username
4526 // Don't kill gardened sessions - doing so leads to a DoS
4527 // from someone who doesn't need to know the password
4528 {
4529 ip = session[s].ip;
4530 user = session[s].user;
4531 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4532 {
4533 if (i == s) continue;
4534 if (!session[s].opened) continue;
4535 if (ip == session[i].ip)
4536 {
4537 sessionkill(i, "Duplicate IP address");
4538 continue;
4539 }
4540
4541 if (config->allow_duplicate_users) continue;
4542 if (session[s].walled_garden || session[i].walled_garden) continue;
4543 if (!strcasecmp(user, session[i].user))
4544 sessionkill(i, "Duplicate session for users");
4545 }
4546 }
4547
4548 {
4549 int routed = 0;
4550
4551 // Add the route for this session.
4552 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4553 {
4554 if ((session[s].ip & session[s].route[r].mask) ==
4555 (session[s].route[r].ip & session[s].route[r].mask))
4556 routed++;
4557
4558 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4559 }
4560
4561 // Static IPs need to be routed if not already
4562 // convered by a Framed-Route. Anything else is part
4563 // of the IP address pool and is already routed, it
4564 // just needs to be added to the IP cache.
4565 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4566 if (session[s].ip_pool_index == -1) // static ip
4567 {
4568 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4569 }
4570 else
4571 cache_ipmap(session[s].ip, s);
4572 }
4573
4574 sess_local[s].lcp_authtype = 0; // RADIUS authentication complete
4575 lcp_open(s, t); // transition to Network phase and send initial IPCP
4576
4577 // Run the plugin's against this new session.
4578 {
4579 struct param_new_session data = { &tunnel[t], &session[s] };
4580 run_plugins(PLUGIN_NEW_SESSION, &data);
4581 }
4582
4583 // Allocate TBFs if throttled
4584 if (session[s].throttle_in || session[s].throttle_out)
4585 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4586
4587 session[s].last_packet = time_now;
4588
4589 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4590 fmtaddr(htonl(session[s].ip), 0),
4591 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4592
4593 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4594
4595 return 1; // RADIUS OK and IP allocated, done...
4596 }
4597
4598 //
4599 // This session just got dropped on us by the master or something.
4600 // Make sure our tables up up to date...
4601 //
4602 int load_session(sessionidt s, sessiont *new)
4603 {
4604 int i;
4605 int newip = 0;
4606
4607 // Sanity checks.
4608 if (new->ip_pool_index >= MAXIPPOOL ||
4609 new->tunnel >= MAXTUNNEL)
4610 {
4611 LOG(0, s, 0, "Strange session update received!\n");
4612 // FIXME! What to do here?
4613 return 0;
4614 }
4615
4616 //
4617 // Ok. All sanity checks passed. Now we're committed to
4618 // loading the new session.
4619 //
4620
4621 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4622
4623 // See if routes/ip cache need updating
4624 if (new->ip != session[s].ip)
4625 newip++;
4626
4627 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4628 if (new->route[i].ip != session[s].route[i].ip ||
4629 new->route[i].mask != session[s].route[i].mask)
4630 newip++;
4631
4632 // needs update
4633 if (newip)
4634 {
4635 int routed = 0;
4636
4637 // remove old routes...
4638 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4639 {
4640 if ((session[s].ip & session[s].route[i].mask) ==
4641 (session[s].route[i].ip & session[s].route[i].mask))
4642 routed++;
4643
4644 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4645 }
4646
4647 // ...ip
4648 if (session[s].ip)
4649 {
4650 if (session[s].ip_pool_index == -1) // static IP
4651 {
4652 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4653 }
4654 else // It's part of the IP pool, remove it manually.
4655 uncache_ipmap(session[s].ip);
4656 }
4657
4658 routed = 0;
4659
4660 // add new routes...
4661 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4662 {
4663 if ((new->ip & new->route[i].mask) ==
4664 (new->route[i].ip & new->route[i].mask))
4665 routed++;
4666
4667 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4668 }
4669
4670 // ...ip
4671 if (new->ip)
4672 {
4673 // If there's a new one, add it.
4674 if (new->ip_pool_index == -1)
4675 {
4676 if (!routed) routeset(s, new->ip, 0, 0, 1);
4677 }
4678 else
4679 cache_ipmap(new->ip, s);
4680 }
4681 }
4682
4683 // check v6 routing
4684 if (new->ipv6prefixlen && new->ppp.ipv6cp == Opened && session[s].ppp.ipv6cp != Opened)
4685 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4686
4687 // check filters
4688 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4689 {
4690 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4691 new->filter_in = 0;
4692 }
4693
4694 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4695 {
4696 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4697 new->filter_out = 0;
4698 }
4699
4700 if (new->filter_in != session[s].filter_in)
4701 {
4702 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4703 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4704 }
4705
4706 if (new->filter_out != session[s].filter_out)
4707 {
4708 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4709 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4710 }
4711
4712 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4713 // for walking the sessions to forward byte counts to the master.
4714 config->cluster_highest_sessionid = s;
4715
4716 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4717
4718 // Do fixups into address pool.
4719 if (new->ip_pool_index != -1)
4720 fix_address_pool(s);
4721
4722 return 1;
4723 }
4724
4725 static void initplugins()
4726 {
4727 int i;
4728
4729 loaded_plugins = ll_init();
4730 // Initialize the plugins to nothing
4731 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4732 plugins[i] = ll_init();
4733 }
4734
4735 static void *open_plugin(char *plugin_name, int load)
4736 {
4737 char path[256] = "";
4738
4739 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4740 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4741 return dlopen(path, RTLD_NOW);
4742 }
4743
4744 // plugin callback to get a config value
4745 static void *getconfig(char *key, enum config_typet type)
4746 {
4747 int i;
4748
4749 for (i = 0; config_values[i].key; i++)
4750 {
4751 if (!strcmp(config_values[i].key, key))
4752 {
4753 if (config_values[i].type == type)
4754 return ((void *) config) + config_values[i].offset;
4755
4756 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4757 key, type, config_values[i].type);
4758
4759 return 0;
4760 }
4761 }
4762
4763 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4764 return 0;
4765 }
4766
4767 static int add_plugin(char *plugin_name)
4768 {
4769 static struct pluginfuncs funcs = {
4770 _log,
4771 _log_hex,
4772 fmtaddr,
4773 sessionbyuser,
4774 sessiontbysessionidt,
4775 sessionidtbysessiont,
4776 radiusnew,
4777 radiussend,
4778 getconfig,
4779 sessionshutdown,
4780 sessionkill,
4781 throttle_session,
4782 cluster_send_session,
4783 };
4784
4785 void *p = open_plugin(plugin_name, 1);
4786 int (*initfunc)(struct pluginfuncs *);
4787 int i;
4788
4789 if (!p)
4790 {
4791 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4792 return -1;
4793 }
4794
4795 if (ll_contains(loaded_plugins, p))
4796 {
4797 dlclose(p);
4798 return 0; // already loaded
4799 }
4800
4801 {
4802 int *v = dlsym(p, "plugin_api_version");
4803 if (!v || *v != PLUGIN_API_VERSION)
4804 {
4805 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4806 dlclose(p);
4807 return -1;
4808 }
4809 }
4810
4811 if ((initfunc = dlsym(p, "plugin_init")))
4812 {
4813 if (!initfunc(&funcs))
4814 {
4815 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4816 dlclose(p);
4817 return -1;
4818 }
4819 }
4820
4821 ll_push(loaded_plugins, p);
4822
4823 for (i = 0; i < max_plugin_functions; i++)
4824 {
4825 void *x;
4826 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4827 {
4828 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4829 ll_push(plugins[i], x);
4830 }
4831 }
4832
4833 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4834 return 1;
4835 }
4836
4837 static void run_plugin_done(void *plugin)
4838 {
4839 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4840
4841 if (donefunc)
4842 donefunc();
4843 }
4844
4845 static int remove_plugin(char *plugin_name)
4846 {
4847 void *p = open_plugin(plugin_name, 0);
4848 int loaded = 0;
4849
4850 if (!p)
4851 return -1;
4852
4853 if (ll_contains(loaded_plugins, p))
4854 {
4855 int i;
4856 for (i = 0; i < max_plugin_functions; i++)
4857 {
4858 void *x;
4859 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4860 ll_delete(plugins[i], x);
4861 }
4862
4863 ll_delete(loaded_plugins, p);
4864 run_plugin_done(p);
4865 loaded = 1;
4866 }
4867
4868 dlclose(p);
4869 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4870 return loaded;
4871 }
4872
4873 int run_plugins(int plugin_type, void *data)
4874 {
4875 int (*func)(void *data);
4876
4877 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4878 return PLUGIN_RET_ERROR;
4879
4880 ll_reset(plugins[plugin_type]);
4881 while ((func = ll_next(plugins[plugin_type])))
4882 {
4883 int r = func(data);
4884
4885 if (r != PLUGIN_RET_OK)
4886 return r; // stop here
4887 }
4888
4889 return PLUGIN_RET_OK;
4890 }
4891
4892 static void plugins_done()
4893 {
4894 void *p;
4895
4896 ll_reset(loaded_plugins);
4897 while ((p = ll_next(loaded_plugins)))
4898 run_plugin_done(p);
4899 }
4900
4901 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen)
4902 {
4903 struct nsctl request;
4904 struct nsctl response;
4905 int type = unpack_control(&request, buf, len);
4906 int r;
4907 void *p;
4908
4909 if (log_stream && config->debug >= 4)
4910 {
4911 if (type < 0)
4912 {
4913 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4914 fmtaddr(addr->sin_addr.s_addr, 0), type);
4915 }
4916 else
4917 {
4918 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4919 dump_control(&request, log_stream);
4920 }
4921 }
4922
4923 switch (type)
4924 {
4925 case NSCTL_REQ_LOAD:
4926 if (request.argc != 1)
4927 {
4928 response.type = NSCTL_RES_ERR;
4929 response.argc = 1;
4930 response.argv[0] = "name of plugin required";
4931 }
4932 else if ((r = add_plugin(request.argv[0])) < 1)
4933 {
4934 response.type = NSCTL_RES_ERR;
4935 response.argc = 1;
4936 response.argv[0] = !r
4937 ? "plugin already loaded"
4938 : "error loading plugin";
4939 }
4940 else
4941 {
4942 response.type = NSCTL_RES_OK;
4943 response.argc = 0;
4944 }
4945
4946 break;
4947
4948 case NSCTL_REQ_UNLOAD:
4949 if (request.argc != 1)
4950 {
4951 response.type = NSCTL_RES_ERR;
4952 response.argc = 1;
4953 response.argv[0] = "name of plugin required";
4954 }
4955 else if ((r = remove_plugin(request.argv[0])) < 1)
4956 {
4957 response.type = NSCTL_RES_ERR;
4958 response.argc = 1;
4959 response.argv[0] = !r
4960 ? "plugin not loaded"
4961 : "plugin not found";
4962 }
4963 else
4964 {
4965 response.type = NSCTL_RES_OK;
4966 response.argc = 0;
4967 }
4968
4969 break;
4970
4971 case NSCTL_REQ_HELP:
4972 response.type = NSCTL_RES_OK;
4973 response.argc = 0;
4974
4975 ll_reset(loaded_plugins);
4976 while ((p = ll_next(loaded_plugins)))
4977 {
4978 char **help = dlsym(p, "plugin_control_help");
4979 while (response.argc < 0xff && help && *help)
4980 response.argv[response.argc++] = *help++;
4981 }
4982
4983 break;
4984
4985 case NSCTL_REQ_CONTROL:
4986 {
4987 struct param_control param = {
4988 config->cluster_iam_master,
4989 request.argc,
4990 request.argv,
4991 0,
4992 NULL,
4993 };
4994
4995 int r = run_plugins(PLUGIN_CONTROL, &param);
4996
4997 if (r == PLUGIN_RET_ERROR)
4998 {
4999 response.type = NSCTL_RES_ERR;
5000 response.argc = 1;
5001 response.argv[0] = param.additional
5002 ? param.additional
5003 : "error returned by plugin";
5004 }
5005 else if (r == PLUGIN_RET_NOTMASTER)
5006 {
5007 static char msg[] = "must be run on master: 000.000.000.000";
5008
5009 response.type = NSCTL_RES_ERR;
5010 response.argc = 1;
5011 if (config->cluster_master_address)
5012 {
5013 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
5014 response.argv[0] = msg;
5015 }
5016 else
5017 {
5018 response.argv[0] = "must be run on master: none elected";
5019 }
5020 }
5021 else if (!(param.response & NSCTL_RESPONSE))
5022 {
5023 response.type = NSCTL_RES_ERR;
5024 response.argc = 1;
5025 response.argv[0] = param.response
5026 ? "unrecognised response value from plugin"
5027 : "unhandled action";
5028 }
5029 else
5030 {
5031 response.type = param.response;
5032 response.argc = 0;
5033 if (param.additional)
5034 {
5035 response.argc = 1;
5036 response.argv[0] = param.additional;
5037 }
5038 }
5039 }
5040
5041 break;
5042
5043 default:
5044 response.type = NSCTL_RES_ERR;
5045 response.argc = 1;
5046 response.argv[0] = "error unpacking control packet";
5047 }
5048
5049 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
5050 if (!buf)
5051 {
5052 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
5053 return;
5054 }
5055
5056 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
5057 if (r > 0)
5058 {
5059 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
5060 if (log_stream && config->debug >= 4)
5061 {
5062 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
5063 dump_control(&response, log_stream);
5064 }
5065 }
5066 else
5067 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
5068 fmtaddr(addr->sin_addr.s_addr, 0), r);
5069
5070 free(buf);
5071 }
5072
5073 static tunnelidt new_tunnel()
5074 {
5075 tunnelidt i;
5076 for (i = 1; i < MAXTUNNEL; i++)
5077 {
5078 if (tunnel[i].state == TUNNELFREE)
5079 {
5080 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
5081 if (i > config->cluster_highest_tunnelid)
5082 config->cluster_highest_tunnelid = i;
5083 return i;
5084 }
5085 }
5086 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
5087 return 0;
5088 }
5089
5090 //
5091 // We're becoming the master. Do any required setup..
5092 //
5093 // This is principally telling all the plugins that we're
5094 // now a master, and telling them about all the sessions
5095 // that are active too..
5096 //
5097 void become_master(void)
5098 {
5099 int s, i;
5100 static struct event_data d[RADIUS_FDS];
5101 struct epoll_event e;
5102
5103 run_plugins(PLUGIN_BECOME_MASTER, NULL);
5104
5105 // running a bunch of iptables commands is slow and can cause
5106 // the master to drop tunnels on takeover--kludge around the
5107 // problem by forking for the moment (note: race)
5108 if (!fork_and_close())
5109 {
5110 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5111 {
5112 if (!session[s].opened) // Not an in-use session.
5113 continue;
5114
5115 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
5116 }
5117 exit(0);
5118 }
5119
5120 // add radius fds
5121 e.events = EPOLLIN;
5122 for (i = 0; i < RADIUS_FDS; i++)
5123 {
5124 d[i].type = FD_TYPE_RADIUS;
5125 d[i].index = i;
5126 e.data.ptr = &d[i];
5127
5128 epoll_ctl(epollfd, EPOLL_CTL_ADD, radfds[i], &e);
5129 }
5130 }
5131
5132 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
5133 {
5134 int s, i;
5135 int count = 0;
5136 int buckets[64];
5137
5138 if (CLI_HELP_REQUESTED)
5139 return CLI_HELP_NO_ARGS;
5140
5141 time(&time_now);
5142 for (i = 0; i < 64;++i) buckets[i] = 0;
5143
5144 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5145 {
5146 int idle;
5147 if (!session[s].opened)
5148 continue;
5149
5150 idle = time_now - session[s].last_packet;
5151 idle /= 5 ; // In multiples of 5 seconds.
5152 if (idle < 0)
5153 idle = 0;
5154 if (idle > 63)
5155 idle = 63;
5156
5157 ++count;
5158 ++buckets[idle];
5159 }
5160
5161 for (i = 0; i < 63; ++i)
5162 {
5163 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
5164 }
5165 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
5166 cli_print(cli, "%d total sessions open.", count);
5167 return CLI_OK;
5168 }
5169
5170 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
5171 {
5172 int s, i;
5173 int count = 0;
5174 int buckets[64];
5175
5176 if (CLI_HELP_REQUESTED)
5177 return CLI_HELP_NO_ARGS;
5178
5179 time(&time_now);
5180 for (i = 0; i < 64;++i) buckets[i] = 0;
5181
5182 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
5183 {
5184 int open = 0, d;
5185 if (!session[s].opened)
5186 continue;
5187
5188 d = time_now - session[s].opened;
5189 if (d < 0)
5190 d = 0;
5191 while (d > 1 && open < 32)
5192 {
5193 ++open;
5194 d >>= 1; // half.
5195 }
5196 ++count;
5197 ++buckets[open];
5198 }
5199
5200 s = 1;
5201 for (i = 0; i < 30; ++i)
5202 {
5203 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
5204 s <<= 1;
5205 }
5206 cli_print(cli, "%d total sessions open.", count);
5207 return CLI_OK;
5208 }
5209
5210 /* Unhide an avp.
5211 *
5212 * This unencodes the AVP using the L2TP secret and the previously
5213 * stored random vector. It overwrites the hidden data with the
5214 * unhidden AVP subformat.
5215 */
5216 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
5217 {
5218 MD5_CTX ctx;
5219 uint8_t digest[16];
5220 uint8_t *last;
5221 size_t d = 0;
5222 uint16_t m = htons(type);
5223
5224 // Compute initial pad
5225 MD5_Init(&ctx);
5226 MD5_Update(&ctx, (unsigned char *) &m, 2);
5227 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5228 MD5_Update(&ctx, vector, vec_len);
5229 MD5_Final(digest, &ctx);
5230
5231 // pointer to last decoded 16 octets
5232 last = value;
5233
5234 while (len > 0)
5235 {
5236 // calculate a new pad based on the last decoded block
5237 if (d >= sizeof(digest))
5238 {
5239 MD5_Init(&ctx);
5240 MD5_Update(&ctx, config->l2tp_secret, strlen(config->l2tp_secret));
5241 MD5_Update(&ctx, last, sizeof(digest));
5242 MD5_Final(digest, &ctx);
5243
5244 d = 0;
5245 last = value;
5246 }
5247
5248 *value++ ^= digest[d++];
5249 len--;
5250 }
5251 }
5252
5253 int find_filter(char const *name, size_t len)
5254 {
5255 int free = -1;
5256 int i;
5257
5258 for (i = 0; i < MAXFILTER; i++)
5259 {
5260 if (!*ip_filters[i].name)
5261 {
5262 if (free < 0)
5263 free = i;
5264
5265 continue;
5266 }
5267
5268 if (strlen(ip_filters[i].name) != len)
5269 continue;
5270
5271 if (!strncmp(ip_filters[i].name, name, len))
5272 return i;
5273 }
5274
5275 return free;
5276 }
5277
5278 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
5279 {
5280 switch (p->op)
5281 {
5282 case FILTER_PORT_OP_EQ: return port == p->port;
5283 case FILTER_PORT_OP_NEQ: return port != p->port;
5284 case FILTER_PORT_OP_GT: return port > p->port;
5285 case FILTER_PORT_OP_LT: return port < p->port;
5286 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
5287 }
5288
5289 return 0;
5290 }
5291
5292 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
5293 {
5294 switch (op)
5295 {
5296 case FILTER_FLAG_OP_ANY:
5297 return (flags & sflags) || (~flags & cflags);
5298
5299 case FILTER_FLAG_OP_ALL:
5300 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
5301
5302 case FILTER_FLAG_OP_EST:
5303 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
5304 }
5305
5306 return 0;
5307 }
5308
5309 int ip_filter(uint8_t *buf, int len, uint8_t filter)
5310 {
5311 uint16_t frag_offset;
5312 uint8_t proto;
5313 in_addr_t src_ip;
5314 in_addr_t dst_ip;
5315 uint16_t src_port = 0;
5316 uint16_t dst_port = 0;
5317 uint8_t flags = 0;
5318 ip_filter_rulet *rule;
5319
5320 if (len < 20) // up to end of destination address
5321 return 0;
5322
5323 if ((*buf >> 4) != 4) // IPv4
5324 return 0;
5325
5326 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
5327 proto = buf[9];
5328 src_ip = *(in_addr_t *) (buf + 12);
5329 dst_ip = *(in_addr_t *) (buf + 16);
5330
5331 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
5332 {
5333 int l = (buf[0] & 0xf) * 4; // length of IP header
5334 if (len < l + 4) // ports
5335 return 0;
5336
5337 src_port = ntohs(*(uint16_t *) (buf + l));
5338 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
5339 if (proto == IPPROTO_TCP)
5340 {
5341 if (len < l + 14) // flags
5342 return 0;
5343
5344 flags = buf[l + 13] & 0x3f;
5345 }
5346 }
5347
5348 for (rule = ip_filters[filter].rules; rule->action; rule++)
5349 {
5350 if (rule->proto != IPPROTO_IP && proto != rule->proto)
5351 continue;
5352
5353 if (rule->src_wild != INADDR_BROADCAST &&
5354 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
5355 continue;
5356
5357 if (rule->dst_wild != INADDR_BROADCAST &&
5358 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
5359 continue;
5360
5361 if (frag_offset)
5362 {
5363 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
5364 continue;
5365 }
5366 else
5367 {
5368 if (rule->frag)
5369 continue;
5370
5371 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5372 {
5373 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5374 continue;
5375
5376 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5377 continue;
5378
5379 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5380 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5381 continue;
5382 }
5383 }
5384
5385 // matched
5386 rule->counter++;
5387 return rule->action == FILTER_ACTION_PERMIT;
5388 }
5389
5390 // default deny
5391 return 0;
5392 }