5ed1dce759283ece4c3c2f8560d46c9772385c07
[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 1.83 2005-02-09 00:45:34 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 /* BGP */
56
57 // Globals
58 configt *config = NULL; // all configuration
59 int tunfd = -1; // tun interface file handle. (network device)
60 int udpfd = -1; // UDP file handle
61 int controlfd = -1; // Control signal handle
62 int clifd = -1; // Socket listening for CLI connections.
63 int snoopfd = -1; // UDP file handle for sending out intercept data
64 int *radfds = NULL; // RADIUS requests file handles
65 int ifrfd = -1; // File descriptor for routing, etc
66 int ifr6fd = -1; // File descriptor for IPv6 routing, etc
67 static int rand_fd = -1; // Random data source
68 time_t basetime = 0; // base clock
69 char hostname[1000] = ""; // us.
70 static int tunidx; // ifr_ifindex of tun device
71 static uint32_t sessionid = 0; // session id for radius accounting
72 static int syslog_log = 0; // are we logging to syslog
73 static FILE *log_stream = NULL; // file handle for direct logging (i.e. direct into file, not via syslog).
74 extern int cluster_sockfd; // Intra-cluster communications socket.
75 uint32_t last_id = 0; // Last used PPP SID. Can I kill this?? -- mo
76
77 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
78 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
79
80 static void *ip_hash[256]; // Mapping from IP address to session structures.
81 struct ipv6radix {
82 int sess;
83 struct ipv6radix *branch;
84 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
85
86 // Traffic counters.
87 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
88 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
89 uint32_t eth_tx = 0;
90
91 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
92 time_t time_now = 0; // Current time in seconds since epoch.
93 static char time_now_string[64] = {0}; // Current time as a string.
94 static char main_quit = 0; // True if we're in the process of exiting.
95 linked_list *loaded_plugins;
96 linked_list *plugins[MAX_PLUGIN_TYPES];
97
98 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
99 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
100
101 config_descriptt config_values[] = {
102 CONFIG("debug", debug, INT),
103 CONFIG("log_file", log_filename, STRING),
104 CONFIG("pid_file", pid_file, STRING),
105 CONFIG("random_device", random_device, STRING),
106 CONFIG("l2tp_secret", l2tpsecret, STRING),
107 CONFIG("primary_dns", default_dns1, IPv4),
108 CONFIG("secondary_dns", default_dns2, IPv4),
109 CONFIG("primary_radius", radiusserver[0], IPv4),
110 CONFIG("secondary_radius", radiusserver[1], IPv4),
111 CONFIG("primary_radius_port", radiusport[0], SHORT),
112 CONFIG("secondary_radius_port", radiusport[1], SHORT),
113 CONFIG("radius_accounting", radius_accounting, BOOL),
114 CONFIG("radius_secret", radiussecret, STRING),
115 CONFIG("radius_authtypes", radius_authtypes_s, STRING),
116 CONFIG("bind_address", bind_address, IPv4),
117 CONFIG("peer_address", peer_address, IPv4),
118 CONFIG("send_garp", send_garp, BOOL),
119 CONFIG("throttle_speed", rl_rate, UNSIGNED_LONG),
120 CONFIG("throttle_buckets", num_tbfs, INT),
121 CONFIG("accounting_dir", accounting_dir, STRING),
122 CONFIG("setuid", target_uid, INT),
123 CONFIG("dump_speed", dump_speed, BOOL),
124 CONFIG("cleanup_interval", cleanup_interval, INT),
125 CONFIG("multi_read_count", multi_read_count, INT),
126 CONFIG("scheduler_fifo", scheduler_fifo, BOOL),
127 CONFIG("lock_pages", lock_pages, BOOL),
128 CONFIG("icmp_rate", icmp_rate, INT),
129 CONFIG("packet_limit", max_packets, INT),
130 CONFIG("cluster_address", cluster_address, IPv4),
131 CONFIG("cluster_interface", cluster_interface, STRING),
132 CONFIG("cluster_hb_interval", cluster_hb_interval, INT),
133 CONFIG("cluster_hb_timeout", cluster_hb_timeout, INT),
134 CONFIG("ipv6_prefix", ipv6_prefix, IPv6),
135 { NULL, 0, 0, 0 },
136 };
137
138 static char *plugin_functions[] = {
139 NULL,
140 "plugin_pre_auth",
141 "plugin_post_auth",
142 "plugin_packet_rx",
143 "plugin_packet_tx",
144 "plugin_timer",
145 "plugin_new_session",
146 "plugin_kill_session",
147 "plugin_control",
148 "plugin_radius_response",
149 "plugin_become_master",
150 "plugin_new_session_master",
151 };
152
153 #define max_plugin_functions (sizeof(plugin_functions) / sizeof(char *))
154
155 // Counters for shutdown sessions
156 static sessiont shut_acct[8192];
157 static sessionidt shut_acct_n = 0;
158
159 tunnelt *tunnel = NULL; // Array of tunnel structures.
160 sessiont *session = NULL; // Array of session structures.
161 sessionlocalt *sess_local = NULL; // Array of local per-session counters.
162 radiust *radius = NULL; // Array of radius structures.
163 ippoolt *ip_address_pool = NULL; // Array of dynamic IP addresses.
164 ip_filtert *ip_filters = NULL; // Array of named filters.
165 static controlt *controlfree = 0;
166 struct Tstats *_statistics = NULL;
167 #ifdef RINGBUFFER
168 struct Tringbuffer *ringbuffer = NULL;
169 #endif
170
171 static void cache_ipmap(in_addr_t ip, int s);
172 static void uncache_ipmap(in_addr_t ip);
173 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s);
174 static void free_ip_address(sessionidt s);
175 static void dump_acct_info(int all);
176 static void sighup_handler(int sig);
177 static void sigalrm_handler(int sig);
178 static void sigterm_handler(int sig);
179 static void sigquit_handler(int sig);
180 static void sigchild_handler(int sig);
181 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response);
182 static void update_config(void);
183 static void read_config_file(void);
184 static void initplugins(void);
185 static int add_plugin(char *plugin_name);
186 static int remove_plugin(char *plugin_name);
187 static void plugins_done(void);
188 static void processcontrol(uint8_t *buf, int len, struct sockaddr_in *addr, int alen);
189 static tunnelidt new_tunnel(void);
190 static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length);
191
192 // return internal time (10ths since process startup)
193 static clockt now(void)
194 {
195 struct timeval t;
196 gettimeofday(&t, 0);
197 return (t.tv_sec - basetime) * 10 + t.tv_usec / 100000 + 1;
198 }
199
200 // work out a retry time based on try number
201 // This is a straight bounded exponential backoff.
202 // Maximum re-try time is 32 seconds. (2^5).
203 clockt backoff(uint8_t try)
204 {
205 if (try > 5) try = 5; // max backoff
206 return now() + 10 * (1 << try);
207 }
208
209
210 //
211 // Log a debug message. Typically called via the LOG macro
212 //
213 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...)
214 {
215 static char message[65536] = {0};
216 va_list ap;
217
218 #ifdef RINGBUFFER
219 if (ringbuffer)
220 {
221 if (++ringbuffer->tail >= RINGBUFFER_SIZE)
222 ringbuffer->tail = 0;
223 if (ringbuffer->tail == ringbuffer->head)
224 if (++ringbuffer->head >= RINGBUFFER_SIZE)
225 ringbuffer->head = 0;
226
227 ringbuffer->buffer[ringbuffer->tail].level = level;
228 ringbuffer->buffer[ringbuffer->tail].session = s;
229 ringbuffer->buffer[ringbuffer->tail].tunnel = t;
230 va_start(ap, format);
231 vsnprintf(ringbuffer->buffer[ringbuffer->tail].message, 4095, format, ap);
232 va_end(ap);
233 }
234 #endif
235
236 if (config->debug < level) return;
237
238 va_start(ap, format);
239 vsnprintf(message, sizeof(message), format, ap);
240
241 if (log_stream)
242 fprintf(log_stream, "%s %02d/%02d %s", time_now_string, t, s, message);
243 else if (syslog_log)
244 syslog(level + 2, "%02d/%02d %s", t, s, message); // We don't need LOG_EMERG or LOG_ALERT
245
246 va_end(ap);
247 }
248
249 void _log_hex(int level, const char *title, const char *data, int maxsize)
250 {
251 int i, j;
252 const uint8_t *d = (const uint8_t *) data;
253
254 if (config->debug < level) return;
255
256 // No support for _log_hex to syslog
257 if (log_stream)
258 {
259 _log(level, 0, 0, "%s (%d bytes):\n", title, maxsize);
260 setvbuf(log_stream, NULL, _IOFBF, 16384);
261
262 for (i = 0; i < maxsize; )
263 {
264 fprintf(log_stream, "%4X: ", i);
265 for (j = i; j < maxsize && j < (i + 16); j++)
266 {
267 fprintf(log_stream, "%02X ", d[j]);
268 if (j == i + 7)
269 fputs(": ", log_stream);
270 }
271
272 for (; j < i + 16; j++)
273 {
274 fputs(" ", log_stream);
275 if (j == i + 7)
276 fputs(": ", log_stream);
277 }
278
279 fputs(" ", log_stream);
280 for (j = i; j < maxsize && j < (i + 16); j++)
281 {
282 if (d[j] >= 0x20 && d[j] < 0x7f && d[j] != 0x20)
283 fputc(d[j], log_stream);
284 else
285 fputc('.', log_stream);
286
287 if (j == i + 7)
288 fputs(" ", log_stream);
289 }
290
291 i = j;
292 fputs("\n", log_stream);
293 }
294
295 fflush(log_stream);
296 setbuf(log_stream, NULL);
297 }
298 }
299
300 // initialise the random generator
301 static void initrandom(char *source)
302 {
303 static char path[sizeof(config->random_device)] = "*undefined*";
304
305 // reinitialise only if we are forced to do so or if the config has changed
306 if (source && !strncmp(path, source, sizeof(path)))
307 return;
308
309 // close previous source, if any
310 if (rand_fd >= 0) close(rand_fd);
311
312 rand_fd = -1;
313
314 if (source)
315 {
316 // register changes
317 snprintf(path, sizeof(path), "%s", source);
318
319 if (*path == '/')
320 {
321 rand_fd = open(path, O_RDONLY|O_NONBLOCK);
322 if (rand_fd < 0)
323 LOG(0, 0, 0, "Error opening the random device %s: %s\n",
324 path, strerror(errno));
325 }
326 }
327
328 // no source: seed prng
329 {
330 unsigned seed = time_now ^ getpid();
331 LOG(4, 0, 0, "Seeding the pseudo random generator: %u\n", seed);
332 srand(seed);
333 }
334 }
335
336 // fill buffer with random data
337 void random_data(uint8_t *buf, int len)
338 {
339 int n = 0;
340
341 CSTAT(random_data);
342 if (rand_fd >= 0)
343 {
344 n = read(rand_fd, buf, len);
345 if (n >= len) return;
346 if (n < 0)
347 {
348 if (errno != EAGAIN)
349 {
350 LOG(0, 0, 0, "Error reading from random source: %s\n",
351 strerror(errno));
352
353 // fall back to rand()
354 initrandom(0);
355 }
356
357 n = 0;
358 }
359 }
360
361 // append missing data
362 while (n < len)
363 // not using the low order bits from the prng stream
364 buf[n++] = (rand() >> 4) & 0xff;
365 }
366
367 // Add a route
368 //
369 // This adds it to the routing table, advertises it
370 // via BGP if enabled, and stuffs it into the
371 // 'sessionbyip' cache.
372 //
373 // 'ip' and 'mask' must be in _host_ order.
374 //
375 static void routeset(sessionidt s, in_addr_t ip, in_addr_t mask, in_addr_t gw, int add)
376 {
377 struct rtentry r;
378 int i;
379
380 if (!mask) mask = 0xffffffff;
381
382 ip &= mask; // Force the ip to be the first one in the route.
383
384 memset(&r, 0, sizeof(r));
385 r.rt_dev = config->tundevice;
386 r.rt_dst.sa_family = AF_INET;
387 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
388 r.rt_gateway.sa_family = AF_INET;
389 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
390 r.rt_genmask.sa_family = AF_INET;
391 *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
392 r.rt_flags = (RTF_UP | RTF_STATIC);
393 if (gw)
394 r.rt_flags |= RTF_GATEWAY;
395 else if (mask == 0xffffffff)
396 r.rt_flags |= RTF_HOST;
397
398 LOG(1, s, 0, "Route %s %s/%s%s%s\n", add ? "add" : "del",
399 fmtaddr(htonl(ip), 0), fmtaddr(htonl(mask), 1),
400 gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
401
402 if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
403 LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
404
405 #ifdef BGP
406 if (add)
407 bgp_add_route(htonl(ip), htonl(mask));
408 else
409 bgp_del_route(htonl(ip), htonl(mask));
410 #endif /* BGP */
411
412 // Add/Remove the IPs to the 'sessionbyip' cache.
413 // Note that we add the zero address in the case of
414 // a network route. Roll on CIDR.
415
416 // Note that 's == 0' implies this is the address pool.
417 // We still cache it here, because it will pre-fill
418 // the malloc'ed tree.
419
420 if (s)
421 {
422 if (!add) // Are we deleting a route?
423 s = 0; // Caching the session as '0' is the same as uncaching.
424
425 for (i = ip; (i&mask) == (ip&mask) ; ++i)
426 cache_ipmap(i, s);
427 }
428 }
429
430 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
431 {
432 struct in6_rtmsg rt;
433 char ipv6addr[INET6_ADDRSTRLEN];
434
435 if (ifr6fd < 0)
436 {
437 LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
438 return;
439 }
440
441 memset(&rt, 0, sizeof(rt));
442
443 memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
444 rt.rtmsg_dst_len = prefixlen;
445 rt.rtmsg_metric = 1;
446 rt.rtmsg_flags = RTF_UP;
447 rt.rtmsg_ifindex = tunidx;
448
449 LOG(1, 0, 0, "Route %s %s/%d\n",
450 add ? "add" : "del",
451 inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
452 prefixlen);
453
454 if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
455 LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
456 strerror(errno));
457
458 // FIXME: need to add BGP routing (RFC2858)
459
460 if (s)
461 {
462 if (!add) // Are we deleting a route?
463 s = 0; // Caching the session as '0' is the same as uncaching.
464
465 cache_ipv6map(ip, prefixlen, s);
466 }
467
468 return;
469 }
470
471 // defined in linux/ipv6.h, but tricky to include from user-space
472 // TODO: move routing to use netlink rather than ioctl
473 struct in6_ifreq {
474 struct in6_addr ifr6_addr;
475 __u32 ifr6_prefixlen;
476 unsigned int ifr6_ifindex;
477 };
478
479 //
480 // Set up TUN interface
481 static void inittun(void)
482 {
483 struct ifreq ifr;
484 struct in6_ifreq ifr6;
485 struct sockaddr_in sin = {0};
486 memset(&ifr, 0, sizeof(ifr));
487 ifr.ifr_flags = IFF_TUN;
488
489 tunfd = open(TUNDEVICE, O_RDWR);
490 if (tunfd < 0)
491 { // fatal
492 LOG(0, 0, 0, "Can't open %s: %s\n", TUNDEVICE, strerror(errno));
493 exit(1);
494 }
495 {
496 int flags = fcntl(tunfd, F_GETFL, 0);
497 fcntl(tunfd, F_SETFL, flags | O_NONBLOCK);
498 }
499 if (ioctl(tunfd, TUNSETIFF, (void *) &ifr) < 0)
500 {
501 LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
502 exit(1);
503 }
504 assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
505 strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
506 ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
507
508 sin.sin_family = AF_INET;
509 sin.sin_addr.s_addr = config->bind_address ? config->bind_address : 0x01010101; // 1.1.1.1
510 memcpy(&ifr.ifr_addr, &sin, sizeof(struct sockaddr));
511
512 if (ioctl(ifrfd, SIOCSIFADDR, (void *) &ifr) < 0)
513 {
514 LOG(0, 0, 0, "Error setting tun address: %s\n", strerror(errno));
515 exit(1);
516 }
517 /* Bump up the qlen to deal with bursts from the network */
518 ifr.ifr_qlen = 1000;
519 if (ioctl(ifrfd, SIOCSIFTXQLEN, (void *) &ifr) < 0)
520 {
521 LOG(0, 0, 0, "Error setting tun queue length: %s\n", strerror(errno));
522 exit(1);
523 }
524 ifr.ifr_flags = IFF_UP;
525 if (ioctl(ifrfd, SIOCSIFFLAGS, (void *) &ifr) < 0)
526 {
527 LOG(0, 0, 0, "Error setting tun flags: %s\n", strerror(errno));
528 exit(1);
529 }
530 if (ioctl(ifrfd, SIOCGIFINDEX, (void *) &ifr) < 0)
531 {
532 LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
533 exit(1);
534 }
535 tunidx = ifr.ifr_ifindex;
536
537 // Only setup IPv6 on the tun device if we have a configured prefix
538 if (config->ipv6_prefix.s6_addr[0] > 0) {
539 ifr6fd = socket(PF_INET6, SOCK_DGRAM, 0);
540
541 // Link local address is FE80::1
542 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
543 ifr6.ifr6_addr.s6_addr[0] = 0xFE;
544 ifr6.ifr6_addr.s6_addr[1] = 0x80;
545 ifr6.ifr6_addr.s6_addr[15] = 1;
546 ifr6.ifr6_prefixlen = 64;
547 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
548 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
549 {
550 LOG(0, 0, 0, "Error setting tun IPv6 link local address:"
551 " %s\n", strerror(errno));
552 }
553
554 // Global address is prefix::1
555 memset(&ifr6.ifr6_addr, 0, sizeof(ifr6.ifr6_addr));
556 ifr6.ifr6_addr = config->ipv6_prefix;
557 ifr6.ifr6_addr.s6_addr[15] = 1;
558 ifr6.ifr6_prefixlen = 64;
559 ifr6.ifr6_ifindex = ifr.ifr_ifindex;
560 if (ioctl(ifr6fd, SIOCSIFADDR, (void *) &ifr6) < 0)
561 {
562 LOG(0, 0, 0, "Error setting tun IPv6 global address: %s\n",
563 strerror(errno));
564 }
565 }
566 }
567
568 // set up UDP port
569 static void initudp(void)
570 {
571 int on = 1;
572 struct sockaddr_in addr;
573
574 // Tunnel
575 memset(&addr, 0, sizeof(addr));
576 addr.sin_family = AF_INET;
577 addr.sin_port = htons(L2TPPORT);
578 addr.sin_addr.s_addr = config->bind_address;
579 udpfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
580 setsockopt(udpfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
581 {
582 int flags = fcntl(udpfd, F_GETFL, 0);
583 fcntl(udpfd, F_SETFL, flags | O_NONBLOCK);
584 }
585 if (bind(udpfd, (void *) &addr, sizeof(addr)) < 0)
586 {
587 LOG(0, 0, 0, "Error in UDP bind: %s\n", strerror(errno));
588 exit(1);
589 }
590 snoopfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
591
592 // Control
593 memset(&addr, 0, sizeof(addr));
594 addr.sin_family = AF_INET;
595 addr.sin_port = htons(NSCTL_PORT);
596 controlfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
597 setsockopt(controlfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
598 if (bind(controlfd, (void *) &addr, sizeof(addr)) < 0)
599 {
600 LOG(0, 0, 0, "Error in control bind: %s\n", strerror(errno));
601 exit(1);
602 }
603 }
604
605 //
606 // Find session by IP, < 1 for not found
607 //
608 // Confusingly enough, this 'ip' must be
609 // in _network_ order. This being the common
610 // case when looking it up from IP packet headers.
611 //
612 // We actually use this cache for two things.
613 // #1. For used IP addresses, this maps to the
614 // session ID that it's used by.
615 // #2. For un-used IP addresses, this maps to the
616 // index into the pool table that contains that
617 // IP address.
618 //
619
620 static int lookup_ipmap(in_addr_t ip)
621 {
622 uint8_t *a = (uint8_t *) &ip;
623 uint8_t **d = (uint8_t **) ip_hash;
624
625 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
626 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
627 if (!(d = (uint8_t **) d[(size_t) *a++])) return 0;
628
629 return (int) (intptr_t) d[(size_t) *a];
630 }
631
632 static int lookup_ipv6map(struct in6_addr ip)
633 {
634 struct ipv6radix *curnode;
635 int i;
636 int s;
637 char ipv6addr[INET6_ADDRSTRLEN];
638
639 curnode = &ipv6_hash[ip.s6_addr[0]];
640 i = 1;
641 s = curnode->sess;
642
643 while (s == 0 && i < 15 && curnode->branch != NULL)
644 {
645 curnode = &curnode->branch[ip.s6_addr[i]];
646 s = curnode->sess;
647 i++;
648 }
649
650 LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
651 inet_ntop(AF_INET6, &ip, ipv6addr,
652 INET6_ADDRSTRLEN),
653 s);
654
655 return s;
656 }
657
658 sessionidt sessionbyip(in_addr_t ip)
659 {
660 int s = lookup_ipmap(ip);
661 CSTAT(sessionbyip);
662
663 if (s > 0 && s < MAXSESSION && session[s].tunnel)
664 return (sessionidt) s;
665
666 return 0;
667 }
668
669 sessionidt sessionbyipv6(struct in6_addr ip)
670 {
671 int s;
672 CSTAT(sessionbyipv6);
673
674 if (!memcmp(&config->ipv6_prefix, &ip, 8) ||
675 (ip.s6_addr[0] == 0xFE && ip.s6_addr[1] == 0x80 &&
676 (ip.s6_addr16[1] == ip.s6_addr16[2] == ip.s6_addr16[3] == 0))) {
677 s = lookup_ipmap(*(in_addr_t *) &ip.s6_addr[8]);
678 } else {
679 s = lookup_ipv6map(ip);
680 }
681
682 if (s > 0 && s < MAXSESSION && session[s].tunnel)
683 return s;
684
685 return 0;
686 }
687
688 //
689 // Take an IP address in HOST byte order and
690 // add it to the sessionid by IP cache.
691 //
692 // (It's actually cached in network order)
693 //
694 static void cache_ipmap(in_addr_t ip, int s)
695 {
696 in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
697 uint8_t *a = (uint8_t *) &nip;
698 uint8_t **d = (uint8_t **) ip_hash;
699 int i;
700
701 for (i = 0; i < 3; i++)
702 {
703 if (!d[(size_t) a[i]])
704 {
705 if (!(d[(size_t) a[i]] = calloc(256, sizeof(void *))))
706 return;
707 }
708
709 d = (uint8_t **) d[(size_t) a[i]];
710 }
711
712 d[(size_t) a[3]] = (uint8_t *) (intptr_t) s;
713
714 if (s > 0)
715 LOG(4, s, session[s].tunnel, "Caching ip address %s\n", fmtaddr(nip, 0));
716
717 else if (s == 0)
718 LOG(4, 0, 0, "Un-caching ip address %s\n", fmtaddr(nip, 0));
719 // else a map to an ip pool index.
720 }
721
722 static void uncache_ipmap(in_addr_t ip)
723 {
724 cache_ipmap(ip, 0); // Assign it to the NULL session.
725 }
726
727 static void cache_ipv6map(struct in6_addr ip, int prefixlen, int s)
728 {
729 int i;
730 int bytes;
731 struct ipv6radix *curnode;
732 char ipv6addr[INET6_ADDRSTRLEN];
733
734 curnode = &ipv6_hash[ip.s6_addr[0]];
735
736 bytes = prefixlen >> 3;
737 i = 1;
738 while (i < bytes) {
739 if (curnode->branch == NULL)
740 {
741 if (!(curnode->branch = calloc(256,
742 sizeof (struct ipv6radix))))
743 return;
744 }
745 curnode = &curnode->branch[ip.s6_addr[i]];
746 i++;
747 }
748
749 curnode->sess = s;
750
751 if (s > 0)
752 LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
753 inet_ntop(AF_INET6, &ip, ipv6addr,
754 INET6_ADDRSTRLEN),
755 prefixlen);
756 else if (s == 0)
757 LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
758 inet_ntop(AF_INET6, &ip, ipv6addr,
759 INET6_ADDRSTRLEN),
760 prefixlen);
761 }
762
763 //
764 // CLI list to dump current ipcache.
765 //
766 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc)
767 {
768 char **d = (char **) ip_hash, **e, **f, **g;
769 int i, j, k, l;
770 int count = 0;
771
772 if (CLI_HELP_REQUESTED)
773 return CLI_HELP_NO_ARGS;
774
775 cli_print(cli, "%7s %s", "Sess#", "IP Address");
776
777 for (i = 0; i < 256; ++i)
778 {
779 if (!d[i])
780 continue;
781 e = (char **) d[i];
782 for (j = 0; j < 256; ++j)
783 {
784 if (!e[j])
785 continue;
786 f = (char **) e[j];
787 for (k = 0; k < 256; ++k)
788 {
789 if (!f[k])
790 continue;
791 g = (char **)f[k];
792 for (l = 0; l < 256; ++l)
793 {
794 if (!g[l])
795 continue;
796 cli_print(cli, "%7d %d.%d.%d.%d", (int) (intptr_t) g[l], i, j, k, l);
797 ++count;
798 }
799 }
800 }
801 }
802 cli_print(cli, "%d entries in cache", count);
803 return CLI_OK;
804 }
805
806
807 // Find session by username, 0 for not found
808 // walled garden users aren't authenticated, so the username is
809 // reasonably useless. Ignore them to avoid incorrect actions
810 //
811 // This is VERY inefficent. Don't call it often. :)
812 //
813 sessionidt sessionbyuser(char *username)
814 {
815 int s;
816 CSTAT(sessionbyuser);
817
818 for (s = 1; s < MAXSESSION ; ++s)
819 {
820 if (session[s].walled_garden)
821 continue; // Skip walled garden users.
822
823 if (!strncmp(session[s].user, username, 128))
824 return s;
825
826 }
827 return 0; // Not found.
828 }
829
830 void send_garp(in_addr_t ip)
831 {
832 int s;
833 struct ifreq ifr;
834 uint8_t mac[6];
835
836 s = socket(PF_INET, SOCK_DGRAM, 0);
837 if (s < 0)
838 {
839 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
840 return;
841 }
842 memset(&ifr, 0, sizeof(ifr));
843 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
844 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
845 {
846 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
847 close(s);
848 return;
849 }
850 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
851 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
852 {
853 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
854 close(s);
855 return;
856 }
857 close(s);
858 sendarp(ifr.ifr_ifindex, mac, ip);
859 }
860
861 // Find session by username, 0 for not found
862 static sessiont *sessiontbysessionidt(sessionidt s)
863 {
864 if (!s || s > MAXSESSION) return NULL;
865 return &session[s];
866 }
867
868 static sessionidt sessionidtbysessiont(sessiont *s)
869 {
870 sessionidt val = s-session;
871 if (s < session || val > MAXSESSION) return 0;
872 return val;
873 }
874
875 // actually send a control message for a specific tunnel
876 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
877 {
878 struct sockaddr_in addr;
879
880 CSTAT(tunnelsend);
881
882 if (!t)
883 {
884 static int backtrace_count = 0;
885 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
886 STAT(tunnel_tx_errors);
887 log_backtrace(backtrace_count, 5)
888 return;
889 }
890
891 if (!tunnel[t].ip)
892 {
893 static int backtrace_count = 0;
894 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
895 log_backtrace(backtrace_count, 5)
896 STAT(tunnel_tx_errors);
897 return;
898 }
899
900 memset(&addr, 0, sizeof(addr));
901 addr.sin_family = AF_INET;
902 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
903 addr.sin_port = htons(tunnel[t].port);
904
905 // sequence expected, if sequence in message
906 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
907
908 // If this is a control message, deal with retries
909 if (*buf & 0x80)
910 {
911 tunnel[t].last = time_now; // control message sent
912 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
913 if (tunnel[t].try > 1)
914 {
915 STAT(tunnel_retries);
916 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
917 }
918 }
919
920 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
921 {
922 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
923 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
924 STAT(tunnel_tx_errors);
925 return;
926 }
927
928 LOG_HEX(5, "Send Tunnel Data", buf, l);
929 STAT(tunnel_tx_packets);
930 INC_STAT(tunnel_tx_bytes, l);
931 }
932
933 //
934 // Tiny helper function to write data to
935 // the 'tun' device.
936 //
937 int tun_write(uint8_t * data, int size)
938 {
939 return write(tunfd, data, size);
940 }
941
942 // process outgoing (to tunnel) IP
943 //
944 static void processipout(uint8_t * buf, int len)
945 {
946 sessionidt s;
947 sessiont *sp;
948 tunnelidt t;
949 in_addr_t ip;
950
951 char *data = buf; // Keep a copy of the originals.
952 int size = len;
953
954 uint8_t b[MAXETHER + 20];
955
956 CSTAT(processipout);
957
958 if (len < MIN_IP_SIZE)
959 {
960 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
961 STAT(tun_rx_errors);
962 return;
963 }
964 if (len >= MAXETHER)
965 {
966 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
967 STAT(tun_rx_errors);
968 return;
969 }
970
971 // Skip the tun header
972 buf += 4;
973 len -= 4;
974
975 // Got an IP header now
976 if (*(uint8_t *)(buf) >> 4 != 4)
977 {
978 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
979 return;
980 }
981
982 ip = *(uint32_t *)(buf + 16);
983 if (!(s = sessionbyip(ip)))
984 {
985 // Is this a packet for a session that doesn't exist?
986 static int rate = 0; // Number of ICMP packets we've sent this second.
987 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
988
989 if (last != time_now)
990 {
991 last = time_now;
992 rate = 0;
993 }
994
995 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
996 {
997 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
998 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
999 }
1000 return;
1001 }
1002 t = session[s].tunnel;
1003 sp = &session[s];
1004
1005 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1006 if (config->max_packets > 0)
1007 {
1008 if (sess_local[s].last_packet_out == TIME)
1009 {
1010 int max = config->max_packets;
1011
1012 // All packets for throttled sessions are handled by the
1013 // master, so further limit by using the throttle rate.
1014 // A bit of a kludge, since throttle rate is in kbps,
1015 // but should still be generous given our average DSL
1016 // packet size is 200 bytes: a limit of 28kbps equates
1017 // to around 180 packets per second.
1018 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1019 max = sp->throttle_out;
1020
1021 if (++sess_local[s].packets_out > max)
1022 {
1023 sess_local[s].packets_dropped++;
1024 return;
1025 }
1026 }
1027 else
1028 {
1029 if (sess_local[s].packets_dropped)
1030 {
1031 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1032 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1033 sess_local[s].packets_dropped, sess_local[s].packets_out,
1034 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1035 sp->user);
1036 }
1037
1038 sess_local[s].last_packet_out = TIME;
1039 sess_local[s].packets_out = 1;
1040 sess_local[s].packets_dropped = 0;
1041 }
1042 }
1043
1044 // run access-list if any
1045 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1046 return;
1047
1048 if (sp->tbf_out)
1049 {
1050 // Are we throttling this session?
1051 if (config->cluster_iam_master)
1052 tbf_queue_packet(sp->tbf_out, data, size);
1053 else
1054 master_throttle_packet(sp->tbf_out, data, size);
1055 return;
1056 }
1057 else if (sp->walled_garden && !config->cluster_iam_master)
1058 {
1059 // We are walled-gardening this
1060 master_garden_packet(s, data, size);
1061 return;
1062 }
1063
1064 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1065
1066 // Add on L2TP header
1067 {
1068 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1069 if (!p) return;
1070 tunnelsend(b, len + (p-b), t); // send it...
1071 }
1072
1073 // Snooping this session, send it to intercept box
1074 if (sp->snoop_ip && sp->snoop_port)
1075 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1076
1077 sp->cout += len; // byte count
1078 sp->total_cout += len; // byte count
1079 sp->pout++;
1080 udp_tx += len;
1081 sess_local[s].cout += len; // To send to master..
1082 }
1083
1084 // process outgoing (to tunnel) IPv6
1085 //
1086 static void processipv6out(uint8_t * buf, int len)
1087 {
1088 sessionidt s;
1089 sessiont *sp;
1090 tunnelidt t;
1091 in_addr_t ip;
1092 struct in6_addr ip6;
1093
1094 char *data = buf; // Keep a copy of the originals.
1095 int size = len;
1096
1097 uint8_t b[MAXETHER + 20];
1098
1099 CSTAT(processipv6out);
1100
1101 if (len < MIN_IP_SIZE)
1102 {
1103 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1104 STAT(tunnel_tx_errors);
1105 return;
1106 }
1107 if (len >= MAXETHER)
1108 {
1109 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1110 STAT(tunnel_tx_errors);
1111 return;
1112 }
1113
1114 // Skip the tun header
1115 buf += 4;
1116 len -= 4;
1117
1118 // Got an IP header now
1119 if (*(uint8_t *)(buf) >> 4 != 6)
1120 {
1121 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1122 return;
1123 }
1124
1125 ip6 = *(struct in6_addr *)(buf+24);
1126 s = sessionbyipv6(ip6);
1127
1128 if (s == 0)
1129 {
1130 ip = *(uint32_t *)(buf + 32);
1131 s = sessionbyip(ip);
1132 }
1133
1134 if (s == 0)
1135 {
1136 // Is this a packet for a session that doesn't exist?
1137 static int rate = 0; // Number of ICMP packets we've sent this second.
1138 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1139
1140 if (last != time_now)
1141 {
1142 last = time_now;
1143 rate = 0;
1144 }
1145
1146 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1147 {
1148 // FIXME: Should send icmp6 host unreachable
1149 }
1150 return;
1151 }
1152 t = session[s].tunnel;
1153 sp = &session[s];
1154
1155 // FIXME: add DoS prevention/filters?
1156
1157 if (sp->tbf_out)
1158 {
1159 // Are we throttling this session?
1160 if (config->cluster_iam_master)
1161 tbf_queue_packet(sp->tbf_out, data, size);
1162 else
1163 master_throttle_packet(sp->tbf_out, data, size);
1164 return;
1165 }
1166 else if (sp->walled_garden && !config->cluster_iam_master)
1167 {
1168 // We are walled-gardening this
1169 master_garden_packet(s, data, size);
1170 return;
1171 }
1172
1173 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1174
1175 // Add on L2TP header
1176 {
1177 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIPV6);
1178 if (!p) return;
1179 tunnelsend(b, len + (p-b), t); // send it...
1180 }
1181
1182 // Snooping this session, send it to intercept box
1183 if (sp->snoop_ip && sp->snoop_port)
1184 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1185
1186 sp->cout += len; // byte count
1187 sp->total_cout += len; // byte count
1188 sp->pout++;
1189 udp_tx += len;
1190 sess_local[s].cout += len; // To send to master..
1191 }
1192
1193 //
1194 // Helper routine for the TBF filters.
1195 // Used to send queued data in to the user!
1196 //
1197 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1198 {
1199 sessiont *sp;
1200 tunnelidt t;
1201 in_addr_t ip;
1202
1203 uint8_t b[MAXETHER + 20];
1204
1205 if (len < 0 || len > MAXETHER)
1206 {
1207 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1208 return;
1209 }
1210
1211 // Skip the tun header
1212 buf += 4;
1213 len -= 4;
1214
1215 ip = *(in_addr_t *)(buf + 16);
1216
1217 if (!session[s].ip)
1218 return;
1219
1220 t = session[s].tunnel;
1221 sp = &session[s];
1222
1223 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1224
1225 // Add on L2TP header
1226 {
1227 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1228 if (!p) return;
1229 tunnelsend(b, len + (p-b), t); // send it...
1230 }
1231
1232 // Snooping this session.
1233 if (sp->snoop_ip && sp->snoop_port)
1234 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1235
1236 sp->cout += len; // byte count
1237 sp->total_cout += len; // byte count
1238 sp->pout++;
1239 udp_tx += len;
1240 sess_local[s].cout += len; // To send to master..
1241 }
1242
1243 // add an AVP (16 bit)
1244 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1245 {
1246 uint16_t l = (m ? 0x8008 : 0x0008);
1247 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1248 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1249 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1250 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1251 c->length += 8;
1252 }
1253
1254 // add an AVP (32 bit)
1255 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1256 {
1257 uint16_t l = (m ? 0x800A : 0x000A);
1258 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1259 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1260 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1261 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1262 c->length += 10;
1263 }
1264
1265 // add an AVP (32 bit)
1266 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1267 {
1268 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1269 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1270 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1271 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1272 memcpy(c->buf + c->length + 6, val, strlen(val));
1273 c->length += 6 + strlen(val);
1274 }
1275
1276 // add a binary AVP
1277 static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
1278 {
1279 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1280 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1281 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1282 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1283 memcpy(c->buf + c->length + 6, val, len);
1284 c->length += 6 + len;
1285 }
1286
1287 // new control connection
1288 static controlt *controlnew(uint16_t mtype)
1289 {
1290 controlt *c;
1291 if (!controlfree)
1292 c = malloc(sizeof(controlt));
1293 else
1294 {
1295 c = controlfree;
1296 controlfree = c->next;
1297 }
1298 assert(c);
1299 c->next = 0;
1300 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1301 c->length = 12;
1302 control16(c, 0, mtype, 1);
1303 return c;
1304 }
1305
1306 // send zero block if nothing is waiting
1307 // (ZLB send).
1308 static void controlnull(tunnelidt t)
1309 {
1310 uint8_t buf[12];
1311 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1312 return;
1313
1314 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1315 *(uint16_t *) (buf + 2) = htons(12); // length
1316 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1317 *(uint16_t *) (buf + 6) = htons(0); // session
1318 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1319 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1320 tunnelsend(buf, 12, t);
1321 }
1322
1323 // add a control message to a tunnel, and send if within window
1324 static void controladd(controlt * c, tunnelidt t, sessionidt s)
1325 {
1326 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1327 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1328 *(uint16_t *) (c->buf + 6) = htons(s ? session[s].far : 0); // session
1329 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1330 tunnel[t].ns++; // advance sequence
1331 // link in message in to queue
1332 if (tunnel[t].controlc)
1333 tunnel[t].controle->next = c;
1334 else
1335 tunnel[t].controls = c;
1336
1337 tunnel[t].controle = c;
1338 tunnel[t].controlc++;
1339
1340 // send now if space in window
1341 if (tunnel[t].controlc <= tunnel[t].window)
1342 {
1343 tunnel[t].try = 0; // first send
1344 tunnelsend(c->buf, c->length, t);
1345 }
1346 }
1347
1348 //
1349 // Throttle or Unthrottle a session
1350 //
1351 // Throttle the data from/to through a session to no more than
1352 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1353 // user).
1354 //
1355 // If either value is -1, the current value is retained for that
1356 // direction.
1357 //
1358 void throttle_session(sessionidt s, int rate_in, int rate_out)
1359 {
1360 if (!session[s].tunnel)
1361 return; // No-one home.
1362
1363 if (!*session[s].user)
1364 return; // User not logged in
1365
1366 if (rate_in >= 0)
1367 {
1368 int bytes = rate_in * 1024 / 8; // kbits to bytes
1369 if (session[s].tbf_in)
1370 free_tbf(session[s].tbf_in);
1371
1372 if (rate_in > 0)
1373 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1374 else
1375 session[s].tbf_in = 0;
1376
1377 session[s].throttle_in = rate_in;
1378 }
1379
1380 if (rate_out >= 0)
1381 {
1382 int bytes = rate_out * 1024 / 8;
1383 if (session[s].tbf_out)
1384 free_tbf(session[s].tbf_out);
1385
1386 if (rate_out > 0)
1387 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1388 else
1389 session[s].tbf_out = 0;
1390
1391 session[s].throttle_out = rate_out;
1392 }
1393 }
1394
1395 // add/remove filters from session (-1 = no change)
1396 static void filter_session(sessionidt s, int filter_in, int filter_out)
1397 {
1398 if (!session[s].tunnel)
1399 return; // No-one home.
1400
1401 if (!*session[s].user)
1402 return; // User not logged in
1403
1404 // paranoia
1405 if (filter_in > MAXFILTER) filter_in = -1;
1406 if (filter_out > MAXFILTER) filter_out = -1;
1407 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1408 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1409
1410 if (filter_in >= 0)
1411 {
1412 if (session[s].filter_in)
1413 ip_filters[session[s].filter_in - 1].used--;
1414
1415 if (filter_in > 0)
1416 ip_filters[filter_in - 1].used++;
1417
1418 session[s].filter_in = filter_in;
1419 }
1420
1421 if (filter_out >= 0)
1422 {
1423 if (session[s].filter_out)
1424 ip_filters[session[s].filter_out - 1].used--;
1425
1426 if (filter_out > 0)
1427 ip_filters[filter_out - 1].used++;
1428
1429 session[s].filter_out = filter_out;
1430 }
1431 }
1432
1433 // start tidy shutdown of session
1434 void sessionshutdown(sessionidt s, char *reason)
1435 {
1436 int walled_garden = session[s].walled_garden;
1437
1438
1439 CSTAT(sessionshutdown);
1440
1441 if (!session[s].tunnel)
1442 {
1443 LOG(3, s, session[s].tunnel, "Called sessionshutdown on a session with no tunnel.\n");
1444 return; // not a live session
1445 }
1446
1447 if (!session[s].die)
1448 {
1449 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1450 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1451 run_plugins(PLUGIN_KILL_SESSION, &data);
1452 }
1453
1454 if (session[s].opened && !walled_garden && !session[s].die)
1455 {
1456 // RADIUS Stop message
1457 uint16_t r = session[s].radius;
1458 if (!r)
1459 {
1460 if (!(r = radiusnew(s)))
1461 {
1462 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1463 STAT(radius_overflow);
1464 }
1465 else
1466 {
1467 random_data(radius[r].auth, sizeof(radius[r].auth));
1468 }
1469 }
1470
1471 if (r && radius[r].state != RADIUSSTOP)
1472 radiussend(r, RADIUSSTOP); // stop, if not already trying
1473
1474 // Save counters to dump to accounting file
1475 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1476 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1477 }
1478
1479 if (session[s].ip)
1480 { // IP allocated, clear and unroute
1481 int r;
1482 int routed = 0;
1483 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1484 {
1485 if ((session[s].ip & session[s].route[r].mask) ==
1486 (session[s].route[r].ip & session[s].route[r].mask))
1487 routed++;
1488
1489 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1490 session[s].route[r].ip = 0;
1491 }
1492
1493 if (session[s].ip_pool_index == -1) // static ip
1494 {
1495 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1496 session[s].ip = 0;
1497 }
1498 else
1499 free_ip_address(s);
1500
1501 // unroute IPv6, if setup
1502 if (session[s].flags & SF_IPV6_ROUTED)
1503 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1504 }
1505
1506 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1507 throttle_session(s, 0, 0);
1508
1509 { // Send CDN
1510 controlt *c = controlnew(14); // sending CDN
1511 control16(c, 1, 3, 1); // result code (admin reasons - TBA make error, general error, add message
1512 control16(c, 14, s, 1); // assigned session (our end)
1513 controladd(c, session[s].tunnel, s); // send the message
1514 }
1515
1516 if (!session[s].die)
1517 session[s].die = now() + 150; // Clean up in 15 seconds
1518
1519 // update filter refcounts
1520 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1521 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1522
1523 cluster_send_session(s);
1524 }
1525
1526 void sendipcp(tunnelidt t, sessionidt s)
1527 {
1528 uint8_t buf[MAXCONTROL];
1529 uint16_t r = session[s].radius;
1530 uint8_t *q;
1531
1532 CSTAT(sendipcp);
1533
1534 if (!r)
1535 r = radiusnew(s);
1536
1537 if (radius[r].state != RADIUSIPCP)
1538 {
1539 radius[r].state = RADIUSIPCP;
1540 radius[r].try = 0;
1541 }
1542
1543 radius[r].retry = backoff(radius[r].try++);
1544 if (radius[r].try > 10)
1545 {
1546 radiusclear(r, s); // Clear radius session.
1547 sessionshutdown(s, "No reply on IPCP");
1548 return;
1549 }
1550
1551 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1552 if (!q) return;
1553
1554 *q = ConfigReq;
1555 q[1] = r << RADIUS_SHIFT; // ID, dont care, we only send one type of request
1556 *(uint16_t *) (q + 2) = htons(10);
1557 q[4] = 3;
1558 q[5] = 6;
1559 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1560 config->bind_address ? config->bind_address :
1561 my_address; // send my IP
1562
1563 tunnelsend(buf, 10 + (q - buf), t); // send it
1564 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1565
1566 // If we have an IPv6 prefix length configured, assume we should
1567 // try to negotiate an IPv6 session as well. Unless we've had a
1568 // (N)ACK for IPV6CP.
1569 if (config->ipv6_prefix.s6_addr[0] > 0 &&
1570 !(session[s].flags & SF_IPV6CP_ACKED) &&
1571 !(session[s].flags & SF_IPV6_NACKED))
1572 {
1573 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
1574 if (!q) return;
1575
1576 *q = ConfigReq;
1577 q[1] = r << RADIUS_SHIFT; // ID, don't care, we
1578 // only send one type
1579 // of request
1580 *(uint16_t *) (q + 2) = htons(14);
1581 q[4] = 1;
1582 q[5] = 10;
1583 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1584 *(uint32_t *) (q + 10) = 0;
1585 q[13] = 1;
1586
1587 tunnelsend(buf, 14 + (q - buf), t); // send it
1588 }
1589 }
1590
1591 // kill a session now
1592 static void sessionkill(sessionidt s, char *reason)
1593 {
1594
1595 CSTAT(sessionkill);
1596
1597 session[s].die = now();
1598 sessionshutdown(s, reason); // close radius/routes, etc.
1599 if (session[s].radius)
1600 radiusclear(session[s].radius, s); // cant send clean accounting data, session is killed
1601
1602 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1603
1604 memset(&session[s], 0, sizeof(session[s]));
1605 session[s].tunnel = T_FREE; // Mark it as free.
1606 session[s].next = sessionfree;
1607 sessionfree = s;
1608 cli_session_actions[s].action = 0;
1609 cluster_send_session(s);
1610 }
1611
1612 static void tunnelclear(tunnelidt t)
1613 {
1614 if (!t) return;
1615 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1616 tunnel[t].state = TUNNELFREE;
1617 }
1618
1619 // kill a tunnel now
1620 static void tunnelkill(tunnelidt t, char *reason)
1621 {
1622 sessionidt s;
1623 controlt *c;
1624
1625 CSTAT(tunnelkill);
1626
1627 tunnel[t].state = TUNNELDIE;
1628
1629 // free control messages
1630 while ((c = tunnel[t].controls))
1631 {
1632 controlt * n = c->next;
1633 tunnel[t].controls = n;
1634 tunnel[t].controlc--;
1635 c->next = controlfree;
1636 controlfree = c;
1637 }
1638 // kill sessions
1639 for (s = 1; s < MAXSESSION; s++)
1640 if (session[s].tunnel == t)
1641 sessionkill(s, reason);
1642
1643 // free tunnel
1644 tunnelclear(t);
1645 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1646 cli_tunnel_actions[s].action = 0;
1647 cluster_send_tunnel(t);
1648 }
1649
1650 // shut down a tunnel cleanly
1651 static void tunnelshutdown(tunnelidt t, char *reason)
1652 {
1653 sessionidt s;
1654
1655 CSTAT(tunnelshutdown);
1656
1657 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1658 {
1659 // never set up, can immediately kill
1660 tunnelkill(t, reason);
1661 return;
1662 }
1663 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1664
1665 // close session
1666 for (s = 1; s < MAXSESSION; s++)
1667 if (session[s].tunnel == t)
1668 sessionshutdown(s, reason);
1669
1670 tunnel[t].state = TUNNELDIE;
1671 tunnel[t].die = now() + 700; // Clean up in 70 seconds
1672 cluster_send_tunnel(t);
1673 // TBA - should we wait for sessions to stop?
1674 { // Send StopCCN
1675 controlt *c = controlnew(4); // sending StopCCN
1676 control16(c, 1, 1, 1); // result code (admin reasons - TBA make error, general error, add message)
1677 control16(c, 9, t, 1); // assigned tunnel (our end)
1678 controladd(c, t, 0); // send the message
1679 }
1680 }
1681
1682 // read and process packet on tunnel (UDP)
1683 void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
1684 {
1685 char *chapresponse = NULL;
1686 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1687 uint8_t *p = buf + 2;
1688
1689
1690 CSTAT(processudp);
1691
1692 udp_rx += len;
1693 udp_rx_pkt++;
1694 LOG_HEX(5, "UDP Data", buf, len);
1695 STAT(tunnel_rx_packets);
1696 INC_STAT(tunnel_rx_bytes, len);
1697 if (len < 6)
1698 {
1699 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1700 STAT(tunnel_rx_errors);
1701 return;
1702 }
1703 if ((buf[1] & 0x0F) != 2)
1704 {
1705 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1706 STAT(tunnel_rx_errors);
1707 return;
1708 }
1709 if (*buf & 0x40)
1710 { // length
1711 l = ntohs(*(uint16_t *) p);
1712 p += 2;
1713 }
1714 t = ntohs(*(uint16_t *) p);
1715 p += 2;
1716 s = ntohs(*(uint16_t *) p);
1717 p += 2;
1718 if (s >= MAXSESSION)
1719 {
1720 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1721 STAT(tunnel_rx_errors);
1722 return;
1723 }
1724 if (t >= MAXTUNNEL)
1725 {
1726 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1727 STAT(tunnel_rx_errors);
1728 return;
1729 }
1730 if (*buf & 0x08)
1731 { // ns/nr
1732 ns = ntohs(*(uint16_t *) p);
1733 p += 2;
1734 nr = ntohs(*(uint16_t *) p);
1735 p += 2;
1736 }
1737 if (*buf & 0x02)
1738 { // offset
1739 uint16_t o = ntohs(*(uint16_t *) p);
1740 p += o + 2;
1741 }
1742 if ((p - buf) > l)
1743 {
1744 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1745 STAT(tunnel_rx_errors);
1746 return;
1747 }
1748 l -= (p - buf);
1749 if (*buf & 0x80)
1750 { // control
1751 uint16_t message = 0xFFFF; // message type
1752 uint8_t fatal = 0;
1753 uint8_t mandatorymessage = 0;
1754 uint8_t chap = 0; // if CHAP being used
1755 uint16_t asession = 0; // assigned session
1756 uint32_t amagic = 0; // magic number
1757 uint8_t aflags = 0; // flags from last LCF
1758 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1759 int requestchap = 0; // do we request PAP instead of original CHAP request?
1760 char called[MAXTEL] = ""; // called number
1761 char calling[MAXTEL] = ""; // calling number
1762
1763 if (!config->cluster_iam_master)
1764 {
1765 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1766 return;
1767 }
1768
1769 if ((*buf & 0xCA) != 0xC8)
1770 {
1771 LOG(1, s, t, "Bad control header %02X\n", *buf);
1772 STAT(tunnel_rx_errors);
1773 return;
1774 }
1775
1776 // check for duplicate tunnel open message
1777 if (!t && ns == 0)
1778 {
1779 int i;
1780
1781 //
1782 // Is this a duplicate of the first packet? (SCCRQ)
1783 //
1784 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1785 {
1786 if (tunnel[i].state != TUNNELOPENING ||
1787 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1788 tunnel[i].port != ntohs(addr->sin_port) )
1789 continue;
1790 t = i;
1791 LOG(3, s, t, "Duplicate SCCRQ?\n");
1792 break;
1793 }
1794 }
1795
1796 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1797 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1798
1799 // if no tunnel specified, assign one
1800 if (!t)
1801 {
1802 if (!(t = new_tunnel()))
1803 {
1804 LOG(1, 0, 0, "No more tunnels\n");
1805 STAT(tunnel_overflow);
1806 return;
1807 }
1808 tunnelclear(t);
1809 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1810 tunnel[t].port = ntohs(addr->sin_port);
1811 tunnel[t].window = 4; // default window
1812 STAT(tunnel_created);
1813 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1814 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1815 }
1816
1817 // If the 'ns' just received is not the 'nr' we're
1818 // expecting, just send an ack and drop it.
1819 //
1820 // if 'ns' is less, then we got a retransmitted packet.
1821 // if 'ns' is greater than missed a packet. Either way
1822 // we should ignore it.
1823 if (ns != tunnel[t].nr)
1824 {
1825 // is this the sequence we were expecting?
1826 STAT(tunnel_rx_errors);
1827 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1828 t, ns, tunnel[t].nr);
1829
1830 if (l) // Is this not a ZLB?
1831 controlnull(t);
1832 return;
1833 }
1834
1835 // This is used to time out old tunnels
1836 tunnel[t].lastrec = time_now;
1837
1838 // check sequence of this message
1839 {
1840 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1841 // some to clear maybe?
1842 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1843 {
1844 controlt *c = tunnel[t].controls;
1845 tunnel[t].controls = c->next;
1846 tunnel[t].controlc--;
1847 c->next = controlfree;
1848 controlfree = c;
1849 skip--;
1850 tunnel[t].try = 0; // we have progress
1851 }
1852
1853 // receiver advance (do here so quoted correctly in any sends below)
1854 if (l) tunnel[t].nr = (ns + 1);
1855 if (skip < 0) skip = 0;
1856 if (skip < tunnel[t].controlc)
1857 {
1858 // some control packets can now be sent that were previous stuck out of window
1859 int tosend = tunnel[t].window - skip;
1860 controlt *c = tunnel[t].controls;
1861 while (c && skip)
1862 {
1863 c = c->next;
1864 skip--;
1865 }
1866 while (c && tosend)
1867 {
1868 tunnel[t].try = 0; // first send
1869 tunnelsend(c->buf, c->length, t);
1870 c = c->next;
1871 tosend--;
1872 }
1873 }
1874 if (!tunnel[t].controlc)
1875 tunnel[t].retry = 0; // caught up
1876 }
1877 if (l)
1878 { // if not a null message
1879 // process AVPs
1880 while (l && !(fatal & 0x80))
1881 {
1882 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1883 uint8_t *b = p;
1884 uint8_t flags = *p;
1885 uint16_t mtype;
1886 p += n; // next
1887 if (l < n)
1888 {
1889 LOG(1, s, t, "Invalid length in AVP\n");
1890 STAT(tunnel_rx_errors);
1891 fatal = flags;
1892 return;
1893 }
1894 l -= n;
1895 if (flags & 0x40)
1896 {
1897 // handle hidden AVPs
1898 if (!*config->l2tpsecret)
1899 {
1900 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
1901 fatal = flags;
1902 continue;
1903 }
1904 if (!session[s].random_vector_length)
1905 {
1906 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
1907 fatal = flags;
1908 continue;
1909 }
1910 LOG(4, s, t, "Hidden AVP\n");
1911 // Unhide the AVP
1912 n = unhide_avp(b, t, s, n);
1913 if (n == 0)
1914 {
1915 fatal = flags;
1916 continue;
1917 }
1918 }
1919 if (*b & 0x3C)
1920 {
1921 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1922 fatal = flags;
1923 continue; // next
1924 }
1925 b += 2;
1926 if (*(uint16_t *) (b))
1927 {
1928 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1929 fatal = flags;
1930 continue; // next
1931 }
1932 b += 2;
1933 mtype = ntohs(*(uint16_t *) (b));
1934 b += 2;
1935 n -= 6;
1936
1937 LOG(4, s, t, " AVP %d (%s) len %d\n", mtype, avp_name(mtype), n);
1938 switch (mtype)
1939 {
1940 case 0: // message type
1941 message = ntohs(*(uint16_t *) b);
1942 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_type(message));
1943 mandatorymessage = flags;
1944 break;
1945 case 1: // result code
1946 {
1947 uint16_t rescode = ntohs(*(uint16_t *) b);
1948 const char* resdesc = "(unknown)";
1949 if (message == 4)
1950 { /* StopCCN */
1951 resdesc = stopccn_result_code(rescode);
1952 }
1953 else if (message == 14)
1954 { /* CDN */
1955 resdesc = cdn_result_code(rescode);
1956 }
1957
1958 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
1959 if (n >= 4)
1960 {
1961 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
1962 LOG(4, s, t, " Error Code %d: %s\n", errcode, error_code(errcode));
1963 }
1964 if (n > 4)
1965 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
1966
1967 break;
1968 }
1969 break;
1970 case 2: // protocol version
1971 {
1972 version = ntohs(*(uint16_t *) (b));
1973 LOG(4, s, t, " Protocol version = %d\n", version);
1974 if (version && version != 0x0100)
1975 { // allow 0.0 and 1.0
1976 LOG(1, s, t, " Bad protocol version %04X\n", version);
1977 fatal = flags;
1978 continue; // next
1979 }
1980 }
1981 break;
1982 case 3: // framing capabilities
1983 // LOG(4, s, t, "Framing capabilities\n");
1984 break;
1985 case 4: // bearer capabilities
1986 // LOG(4, s, t, "Bearer capabilities\n");
1987 break;
1988 case 5: // tie breaker
1989 // We never open tunnels, so we don't care about tie breakers
1990 // LOG(4, s, t, "Tie breaker\n");
1991 continue;
1992 case 6: // firmware revision
1993 // LOG(4, s, t, "Firmware revision\n");
1994 break;
1995 case 7: // host name
1996 memset(tunnel[t].hostname, 0, 128);
1997 memcpy(tunnel[t].hostname, b, (n >= 127) ? 127 : n);
1998 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
1999 // TBA - to send to RADIUS
2000 break;
2001 case 8: // vendor name
2002 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2003 memcpy(tunnel[t].vendor, b, (n >= sizeof(tunnel[t].vendor) - 1) ? sizeof(tunnel[t].vendor) - 1 : n);
2004 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2005 break;
2006 case 9: // assigned tunnel
2007 tunnel[t].far = ntohs(*(uint16_t *) (b));
2008 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2009 break;
2010 case 10: // rx window
2011 tunnel[t].window = ntohs(*(uint16_t *) (b));
2012 if (!tunnel[t].window)
2013 tunnel[t].window = 1; // window of 0 is silly
2014 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2015 break;
2016 case 11: // Challenge
2017 {
2018 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2019 build_chap_response(b, 2, n, &chapresponse);
2020 }
2021 break;
2022 case 13: // Response
2023 // Why did they send a response? We never challenge.
2024 LOG(2, s, t, " received unexpected challenge response\n");
2025 break;
2026
2027 case 14: // assigned session
2028 asession = session[s].far = ntohs(*(uint16_t *) (b));
2029 LOG(4, s, t, " assigned session = %d\n", asession);
2030 break;
2031 case 15: // call serial number
2032 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2033 break;
2034 case 18: // bearer type
2035 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2036 // TBA - for RADIUS
2037 break;
2038 case 19: // framing type
2039 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2040 // TBA
2041 break;
2042 case 21: // called number
2043 memset(called, 0, MAXTEL);
2044 memcpy(called, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
2045 LOG(4, s, t, " Called <%s>\n", called);
2046 break;
2047 case 22: // calling number
2048 memset(calling, 0, MAXTEL);
2049 memcpy(calling, b, (n >= MAXTEL) ? (MAXTEL-1) : n);
2050 LOG(4, s, t, " Calling <%s>\n", calling);
2051 break;
2052 case 23: // subtype
2053 break;
2054 case 24: // tx connect speed
2055 if (n == 4)
2056 {
2057 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2058 }
2059 else
2060 {
2061 // AS5300s send connect speed as a string
2062 char tmp[30] = {0};
2063 memcpy(tmp, b, (n >= 30) ? 30 : n);
2064 session[s].tx_connect_speed = atol(tmp);
2065 }
2066 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2067 break;
2068 case 38: // rx connect speed
2069 if (n == 4)
2070 {
2071 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2072 }
2073 else
2074 {
2075 // AS5300s send connect speed as a string
2076 char tmp[30] = {0};
2077 memcpy(tmp, b, (n >= 30) ? 30 : n);
2078 session[s].rx_connect_speed = atol(tmp);
2079 }
2080 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2081 break;
2082 case 25: // Physical Channel ID
2083 {
2084 uint32_t tmp = ntohl(*(uint32_t *) b);
2085 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2086 break;
2087 }
2088 case 29: // Proxy Authentication Type
2089 {
2090 uint16_t atype = ntohs(*(uint16_t *)b);
2091 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
2092 requestchap = (atype == 2);
2093 break;
2094 }
2095 case 30: // Proxy Authentication Name
2096 {
2097 char authname[64] = {0};
2098 memcpy(authname, b, (n > 63) ? 63 : n);
2099 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2100 authname);
2101 break;
2102 }
2103 case 31: // Proxy Authentication Challenge
2104 {
2105 memcpy(radius[session[s].radius].auth, b, 16);
2106 LOG(4, s, t, " Proxy Auth Challenge\n");
2107 break;
2108 }
2109 case 32: // Proxy Authentication ID
2110 {
2111 uint16_t authid = ntohs(*(uint16_t *)(b));
2112 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2113 if (session[s].radius)
2114 radius[session[s].radius].id = authid;
2115 break;
2116 }
2117 case 33: // Proxy Authentication Response
2118 {
2119 char authresp[64] = {0};
2120 memcpy(authresp, b, (n > 63) ? 63 : n);
2121 LOG(4, s, t, " Proxy Auth Response\n");
2122 break;
2123 }
2124 case 27: // last send lcp
2125 { // find magic number
2126 uint8_t *p = b, *e = p + n;
2127 while (p + 1 < e && p[1] && p + p[1] <= e)
2128 {
2129 if (*p == 5 && p[1] == 6) // Magic-Number
2130 amagic = ntohl(*(uint32_t *) (p + 2));
2131 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol
2132 chap = 1;
2133 else if (*p == 7) // Protocol-Field-Compression
2134 aflags |= SESSIONPFC;
2135 else if (*p == 8) // Address-and-Control-Field-Compression
2136 aflags |= SESSIONACFC;
2137 p += p[1];
2138 }
2139 }
2140 break;
2141 case 28: // last recv lcp confreq
2142 break;
2143 case 26: // Initial Received LCP CONFREQ
2144 break;
2145 case 39: // seq required - we control it as an LNS anyway...
2146 break;
2147 case 36: // Random Vector
2148 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2149 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2150 memcpy(session[s].random_vector, b, n);
2151 session[s].random_vector_length = n;
2152 break;
2153 default:
2154 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2155 fatal = flags;
2156 continue; // next
2157 }
2158 }
2159 // process message
2160 if (fatal & 0x80)
2161 tunnelshutdown(t, "Unknown Mandatory AVP");
2162 else
2163 switch (message)
2164 {
2165 case 1: // SCCRQ - Start Control Connection Request
2166 {
2167 controlt *c = controlnew(2); // sending SCCRP
2168 control16(c, 2, version, 1); // protocol version
2169 control32(c, 3, 3, 1); // framing
2170 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2171 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2172 control16(c, 9, t, 1); // assigned tunnel
2173 controladd(c, t, s); // send the resply
2174 }
2175 tunnel[t].state = TUNNELOPENING;
2176 break;
2177 case 2: // SCCRP
2178 tunnel[t].state = TUNNELOPEN;
2179 break;
2180 case 3: // SCCN
2181 tunnel[t].state = TUNNELOPEN;
2182 controlnull(t); // ack
2183 break;
2184 case 4: // StopCCN
2185 controlnull(t); // ack
2186 tunnelshutdown(t, "Stopped"); // Shut down cleanly
2187 tunnelkill(t, "Stopped"); // Immediately force everything dead
2188 break;
2189 case 6: // HELLO
2190 controlnull(t); // simply ACK
2191 break;
2192 case 7: // OCRQ
2193 // TBA
2194 break;
2195 case 8: // OCRO
2196 // TBA
2197 break;
2198 case 9: // OCCN
2199 // TBA
2200 break;
2201 case 10: // ICRQ
2202 if (!sessionfree)
2203 {
2204 STAT(session_overflow);
2205 tunnelshutdown(t, "No free sessions");
2206 }
2207 else
2208 {
2209 uint16_t r;
2210 controlt *c;
2211
2212 s = sessionfree;
2213 sessionfree = session[s].next;
2214 memset(&session[s], 0, sizeof(session[s]));
2215
2216 if (s > config->cluster_highest_sessionid)
2217 config->cluster_highest_sessionid = s;
2218
2219 // make a RADIUS session
2220 if (!(r = radiusnew(s)))
2221 {
2222 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
2223 sessionkill(s, "no free RADIUS sesions");
2224 return;
2225 }
2226
2227 c = controlnew(11); // sending ICRP
2228 session[s].id = sessionid++;
2229 session[s].opened = time(NULL);
2230 session[s].tunnel = t;
2231 session[s].far = asession;
2232 session[s].last_packet = time_now;
2233 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2234 control16(c, 14, s, 1); // assigned session
2235 controladd(c, t, s); // send the reply
2236
2237 // Generate a random challenge
2238 random_data(radius[r].auth, sizeof(radius[r].auth));
2239 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
2240 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2241 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2242 STAT(session_created);
2243 }
2244 break;
2245 case 11: // ICRP
2246 // TBA
2247 break;
2248 case 12: // ICCN
2249 if (amagic == 0) amagic = time_now;
2250 session[s].magic = amagic; // set magic number
2251 session[s].l2tp_flags = aflags; // set flags received
2252 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
2253 controlnull(t); // ack
2254 // In CHAP state, request PAP instead
2255 if (requestchap)
2256 initlcp(t, s);
2257 break;
2258 case 14: // CDN
2259 controlnull(t); // ack
2260 sessionshutdown(s, "Closed (Received CDN)");
2261 break;
2262 case 0xFFFF:
2263 LOG(1, s, t, "Missing message type\n");
2264 break;
2265 default:
2266 STAT(tunnel_rx_errors);
2267 if (mandatorymessage & 0x80)
2268 tunnelshutdown(t, "Unknown message");
2269 else
2270 LOG(1, s, t, "Unknown message type %d\n", message);
2271 break;
2272 }
2273 if (chapresponse) free(chapresponse);
2274 cluster_send_tunnel(t);
2275 }
2276 else
2277 {
2278 LOG(4, s, t, " Got a ZLB ack\n");
2279 }
2280 }
2281 else
2282 { // data
2283 uint16_t prot;
2284
2285 LOG_HEX(5, "Receive Tunnel Data", p, l);
2286 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2287 { // HDLC address header, discard
2288 p += 2;
2289 l -= 2;
2290 }
2291 if (l < 2)
2292 {
2293 LOG(1, s, t, "Short ppp length %d\n", l);
2294 STAT(tunnel_rx_errors);
2295 return;
2296 }
2297 if (*p & 1)
2298 {
2299 prot = *p++;
2300 l--;
2301 }
2302 else
2303 {
2304 prot = ntohs(*(uint16_t *) p);
2305 p += 2;
2306 l -= 2;
2307 }
2308
2309 if (s && !session[s].tunnel) // Is something wrong??
2310 {
2311 if (!config->cluster_iam_master)
2312 {
2313 // Pass it off to the master to deal with..
2314 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2315 return;
2316 }
2317
2318
2319 LOG(1, s, t, "UDP packet contains session %d but no session[%d].tunnel "
2320 "exists (LAC said tunnel = %d). Dropping packet.\n", s, s, t);
2321
2322 STAT(tunnel_rx_errors);
2323 return;
2324 }
2325
2326 if (prot == PPPPAP)
2327 {
2328 session[s].last_packet = time_now;
2329 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2330 processpap(t, s, p, l);
2331 }
2332 else if (prot == PPPCHAP)
2333 {
2334 session[s].last_packet = time_now;
2335 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2336 processchap(t, s, p, l);
2337 }
2338 else if (prot == PPPLCP)
2339 {
2340 session[s].last_packet = time_now;
2341 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2342 processlcp(t, s, p, l);
2343 }
2344 else if (prot == PPPIPCP)
2345 {
2346 session[s].last_packet = time_now;
2347 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2348 processipcp(t, s, p, l);
2349 }
2350 else if (prot == PPPIPV6CP)
2351 {
2352 if (config->ipv6_prefix.s6_addr[0] > 0)
2353 {
2354 session[s].last_packet = time_now;
2355 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2356 processipv6cp(t, s, p, l);
2357 }
2358 else
2359 {
2360 LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
2361 }
2362 }
2363 else if (prot == PPPCCP)
2364 {
2365 session[s].last_packet = time_now;
2366 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2367 processccp(t, s, p, l);
2368 }
2369 else if (prot == PPPIP)
2370 {
2371 if (session[s].die)
2372 {
2373 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2374 return; // closing session, PPP not processed
2375 }
2376
2377 session[s].last_packet = time_now;
2378 if (session[s].walled_garden && !config->cluster_iam_master)
2379 {
2380 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2381 return;
2382 }
2383
2384 processipin(t, s, p, l);
2385 }
2386 else if (prot == PPPIPV6)
2387 {
2388 if (!config->ipv6_prefix.s6_addr[0] > 0)
2389 {
2390 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2391 return;
2392 }
2393 if (session[s].die)
2394 {
2395 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2396 return; // closing session, PPP not processed
2397 }
2398
2399 session[s].last_packet = time_now;
2400 if (session[s].walled_garden && !config->cluster_iam_master)
2401 {
2402 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2403 return;
2404 }
2405
2406 processipv6in(t, s, p, l);
2407 }
2408 else
2409 {
2410 STAT(tunnel_rx_errors);
2411 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2412 }
2413 }
2414 }
2415
2416 // read and process packet on tun
2417 static void processtun(uint8_t * buf, int len)
2418 {
2419 LOG_HEX(5, "Receive TUN Data", buf, len);
2420 STAT(tun_rx_packets);
2421 INC_STAT(tun_rx_bytes, len);
2422
2423 CSTAT(processtun);
2424
2425 eth_rx_pkt++;
2426 eth_rx += len;
2427 if (len < 22)
2428 {
2429 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2430 STAT(tun_rx_errors);
2431 return;
2432 }
2433
2434 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2435 processipout(buf, len);
2436 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2437 && config->ipv6_prefix.s6_addr[0] > 0)
2438 processipv6out(buf, len);
2439
2440 // Else discard.
2441 }
2442
2443 //
2444 // Maximum number of actions to complete.
2445 // This is to avoid sending out too many packets
2446 // at once.
2447 #define MAX_ACTIONS 500
2448
2449 static int regular_cleanups(void)
2450 {
2451 static sessionidt s = 0; // Next session to check for actions on.
2452 tunnelidt t;
2453 int count=0,i;
2454 uint16_t r;
2455 static clockt next_acct = 0;
2456 static clockt next_shut_acct = 0;
2457 int a;
2458
2459 LOG(3, 0, 0, "Begin regular cleanup\n");
2460
2461 for (r = 1; r < MAXRADIUS; r++)
2462 {
2463 if (!radius[r].state)
2464 continue;
2465 if (radius[r].retry)
2466 {
2467 if (radius[r].retry <= TIME)
2468 radiusretry(r);
2469 } else
2470 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
2471 }
2472 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
2473 {
2474 // check for expired tunnels
2475 if (tunnel[t].die && tunnel[t].die <= TIME)
2476 {
2477 STAT(tunnel_timeout);
2478 tunnelkill(t, "Expired");
2479 continue;
2480 }
2481 // check for message resend
2482 if (tunnel[t].retry && tunnel[t].controlc)
2483 {
2484 // resend pending messages as timeout on reply
2485 if (tunnel[t].retry <= TIME)
2486 {
2487 controlt *c = tunnel[t].controls;
2488 uint8_t w = tunnel[t].window;
2489 tunnel[t].try++; // another try
2490 if (tunnel[t].try > 5)
2491 tunnelkill(t, "Timeout on control message"); // game over
2492 else
2493 while (c && w--)
2494 {
2495 tunnelsend(c->buf, c->length, t);
2496 c = c->next;
2497 }
2498 }
2499 }
2500 // Send hello
2501 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2502 {
2503 controlt *c = controlnew(6); // sending HELLO
2504 controladd(c, t, 0); // send the message
2505 LOG(3, 0, t, "Sending HELLO message\n");
2506 }
2507
2508 // Check for tunnel changes requested from the CLI
2509 if ((a = cli_tunnel_actions[t].action))
2510 {
2511 cli_tunnel_actions[t].action = 0;
2512 if (a & CLI_TUN_KILL)
2513 {
2514 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2515 tunnelshutdown(t, "Requested by administrator");
2516 }
2517 }
2518
2519 }
2520
2521 count = 0;
2522 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2523 {
2524 s++;
2525 if (s > config->cluster_highest_sessionid)
2526 s = 1;
2527
2528 if (!session[s].tunnel) // Session isn't in use
2529 continue;
2530
2531 if (!session[s].die && session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2532 {
2533 // IPCP has not completed yet. Resend
2534 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2535 sendipcp(session[s].tunnel, s);
2536 }
2537
2538 // check for expired sessions
2539 if (session[s].die && session[s].die <= TIME)
2540 {
2541 sessionkill(s, "Expired");
2542 if (++count >= MAX_ACTIONS) break;
2543 continue;
2544 }
2545
2546 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2547 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2548 {
2549 sessionshutdown(s, "No response to LCP ECHO requests");
2550 STAT(session_timeout);
2551 if (++count >= MAX_ACTIONS) break;
2552 continue;
2553 }
2554
2555 // No data in IDLE_TIMEOUT seconds, send LCP ECHO
2556 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2557 {
2558 uint8_t b[MAXCONTROL] = {0};
2559
2560 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2561 if (!q) continue;
2562
2563 *q = EchoReq;
2564 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2565 *(uint16_t *)(q + 2) = htons(8); // Length
2566 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2567
2568 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2569 (int)(time_now - session[s].last_packet));
2570 tunnelsend(b, 24, session[s].tunnel); // send it
2571 if (++count >= MAX_ACTIONS) break;
2572 }
2573
2574 // Check for actions requested from the CLI
2575 if ((a = cli_session_actions[s].action))
2576 {
2577 int send = 0;
2578
2579 cli_session_actions[s].action = 0;
2580 if (a & CLI_SESS_KILL)
2581 {
2582 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2583 sessionshutdown(s, "Requested by administrator");
2584 a = 0; // dead, no need to check for other actions
2585 }
2586
2587 if (a & CLI_SESS_NOSNOOP)
2588 {
2589 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2590 session[s].snoop_ip = 0;
2591 session[s].snoop_port = 0;
2592 send++;
2593 }
2594 else if (a & CLI_SESS_SNOOP)
2595 {
2596 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2597 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2598 cli_session_actions[s].snoop_port);
2599
2600 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2601 session[s].snoop_port = cli_session_actions[s].snoop_port;
2602 send++;
2603 }
2604
2605 if (a & CLI_SESS_NOTHROTTLE)
2606 {
2607 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2608 throttle_session(s, 0, 0);
2609 send++;
2610 }
2611 else if (a & CLI_SESS_THROTTLE)
2612 {
2613 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2614 cli_session_actions[s].throttle_in,
2615 cli_session_actions[s].throttle_out);
2616
2617 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2618 send++;
2619 }
2620
2621 if (a & CLI_SESS_NOFILTER)
2622 {
2623 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2624 filter_session(s, 0, 0);
2625 send++;
2626 }
2627 else if (a & CLI_SESS_FILTER)
2628 {
2629 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2630 cli_session_actions[s].filter_in,
2631 cli_session_actions[s].filter_out);
2632
2633 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2634 send++;
2635 }
2636
2637 if (send)
2638 cluster_send_session(s);
2639
2640 if (++count >= MAX_ACTIONS) break;
2641 }
2642 }
2643
2644 if (*config->accounting_dir)
2645 {
2646 if (next_acct <= TIME)
2647 {
2648 // Dump accounting data
2649 next_acct = TIME + ACCT_TIME;
2650 next_shut_acct = TIME + ACCT_SHUT_TIME;
2651 dump_acct_info(1);
2652 }
2653 else if (next_shut_acct <= TIME)
2654 {
2655 // Dump accounting data for shutdown sessions
2656 next_shut_acct = TIME + ACCT_SHUT_TIME;
2657 if (shut_acct_n)
2658 dump_acct_info(0);
2659 }
2660 }
2661
2662 if (count >= MAX_ACTIONS)
2663 return 1; // Didn't finish!
2664
2665 LOG(3, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2666 return 0;
2667 }
2668
2669
2670 //
2671 // Are we in the middle of a tunnel update, or radius
2672 // requests??
2673 //
2674 static int still_busy(void)
2675 {
2676 int i;
2677 static clockt last_talked = 0;
2678 static clockt start_busy_wait = 0;
2679 if (start_busy_wait == 0)
2680 start_busy_wait = TIME;
2681
2682 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2683 {
2684 if (!tunnel[i].controlc)
2685 continue;
2686
2687 if (last_talked != TIME)
2688 {
2689 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2690 last_talked = TIME;
2691 }
2692 return 1;
2693 }
2694
2695 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2696 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2697 {
2698 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2699 return 0;
2700 }
2701
2702 for (i = 1; i < MAXRADIUS; i++)
2703 {
2704 if (radius[i].state == RADIUSNULL)
2705 continue;
2706 if (radius[i].state == RADIUSWAIT)
2707 continue;
2708
2709 if (last_talked != TIME)
2710 {
2711 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2712 last_talked = TIME;
2713 }
2714 return 1;
2715 }
2716
2717 return 0;
2718 }
2719
2720 static fd_set readset;
2721 static int readset_n = 0;
2722
2723 // main loop - gets packets on tun or udp and processes them
2724 static void mainloop(void)
2725 {
2726 int i;
2727 uint8_t buf[65536];
2728 struct timeval to;
2729 clockt next_cluster_ping = 0; // send initial ping immediately
2730 time_t next_clean = time_now + config->cleanup_interval;
2731
2732 LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2733 udpfd, tunfd, cluster_sockfd, controlfd);
2734
2735 FD_ZERO(&readset);
2736 FD_SET(udpfd, &readset);
2737 FD_SET(tunfd, &readset);
2738 FD_SET(controlfd, &readset);
2739 FD_SET(clifd, &readset);
2740 if (cluster_sockfd) FD_SET(cluster_sockfd, &readset);
2741 readset_n = udpfd;
2742 if (tunfd > readset_n) readset_n = tunfd;
2743 if (controlfd > readset_n) readset_n = controlfd;
2744 if (clifd > readset_n) readset_n = clifd;
2745 if (cluster_sockfd > readset_n) readset_n = cluster_sockfd;
2746
2747 while (!main_quit || still_busy())
2748 {
2749 fd_set r;
2750 int n = readset_n;
2751 #ifdef BGP
2752 fd_set w;
2753 int bgp_set[BGP_NUM_PEERS];
2754 #endif /* BGP */
2755
2756 if (config->reload_config)
2757 {
2758 // Update the config state based on config settings
2759 update_config();
2760 }
2761
2762 memcpy(&r, &readset, sizeof(fd_set));
2763 to.tv_sec = 0;
2764 to.tv_usec = 100000; // 1/10th of a second.
2765
2766 #ifdef BGP
2767 FD_ZERO(&w);
2768 for (i = 0; i < BGP_NUM_PEERS; i++)
2769 {
2770 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2771 if (bgp_set[i] & 1)
2772 {
2773 FD_SET(bgp_peers[i].sock, &r);
2774 if (bgp_peers[i].sock > n)
2775 n = bgp_peers[i].sock;
2776 }
2777
2778 if (bgp_set[i] & 2)
2779 {
2780 FD_SET(bgp_peers[i].sock, &w);
2781 if (bgp_peers[i].sock > n)
2782 n = bgp_peers[i].sock;
2783 }
2784 }
2785
2786 n = select(n + 1, &r, &w, 0, &to);
2787 #else /* BGP */
2788 n = select(n + 1, &r, 0, 0, &to);
2789 #endif /* BGP */
2790
2791 STAT(select_called);
2792
2793 TIME = now();
2794 if (n < 0)
2795 {
2796 if (errno == EINTR ||
2797 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
2798 continue;
2799
2800 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2801 main_quit++;
2802 break;
2803 }
2804 else if (n)
2805 {
2806 struct sockaddr_in addr;
2807 int alen, c, s;
2808 int udp_pkts = 0;
2809 int tun_pkts = 0;
2810 int cluster_pkts = 0;
2811
2812 // nsctl commands
2813 if (FD_ISSET(controlfd, &r))
2814 {
2815 alen = sizeof(addr);
2816 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
2817 n--;
2818 }
2819
2820 // RADIUS responses
2821 if (config->cluster_iam_master)
2822 {
2823 for (i = 0; i < config->num_radfds; i++)
2824 {
2825 if (FD_ISSET(radfds[i], &r))
2826 {
2827 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2828 n--;
2829 }
2830 }
2831 }
2832
2833 // CLI connections
2834 if (FD_ISSET(clifd, &r))
2835 {
2836 int cli;
2837
2838 alen = sizeof(addr);
2839 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
2840 {
2841 cli_do(cli);
2842 close(cli);
2843 }
2844 else
2845 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
2846
2847 n--;
2848 }
2849
2850 #ifdef BGP
2851 for (i = 0; i < BGP_NUM_PEERS; i++)
2852 {
2853 int isr = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0;
2854 int isw = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0;
2855 bgp_process(&bgp_peers[i], isr, isw);
2856 if (isr) n--;
2857 if (isw) n--;
2858 }
2859 #endif /* BGP */
2860
2861 for (c = 0; n && c < config->multi_read_count; c++)
2862 {
2863 // L2TP
2864 if (FD_ISSET(udpfd, &r))
2865 {
2866 alen = sizeof(addr);
2867 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
2868 {
2869 processudp(buf, s, &addr);
2870 udp_pkts++;
2871 }
2872 else
2873 {
2874 FD_CLR(udpfd, &r);
2875 n--;
2876 }
2877 }
2878
2879 // incoming IP
2880 if (FD_ISSET(tunfd, &r))
2881 {
2882 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
2883 {
2884 processtun(buf, s);
2885 tun_pkts++;
2886 }
2887 else
2888 {
2889 FD_CLR(tunfd, &r);
2890 n--;
2891 }
2892 }
2893
2894 // cluster
2895 if (FD_ISSET(cluster_sockfd, &r))
2896 {
2897 alen = sizeof(addr);
2898 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
2899 {
2900 processcluster(buf, s, addr.sin_addr.s_addr);
2901 cluster_pkts++;
2902 }
2903 else
2904 {
2905 FD_CLR(cluster_sockfd, &r);
2906 n--;
2907 }
2908 }
2909 }
2910
2911 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
2912 STAT(multi_read_used);
2913
2914 if (c >= config->multi_read_count)
2915 {
2916 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
2917 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
2918
2919 STAT(multi_read_exceeded);
2920 }
2921 }
2922
2923 // Runs on every machine (master and slaves).
2924 if (cluster_sockfd && next_cluster_ping <= TIME)
2925 {
2926 // Check to see which of the cluster is still alive..
2927
2928 cluster_send_ping(basetime); // Only does anything if we're a slave
2929 cluster_check_master(); // ditto.
2930
2931 cluster_heartbeat(); // Only does anything if we're a master.
2932 cluster_check_slaves(); // ditto.
2933
2934 master_update_counts(); // If we're a slave, send our byte counters to our master.
2935
2936 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
2937 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
2938 else
2939 next_cluster_ping = TIME + config->cluster_hb_interval;
2940 }
2941
2942 // Run token bucket filtering queue..
2943 // Only run it every 1/10th of a second.
2944 // Runs on all machines both master and slave.
2945 {
2946 static clockt last_run = 0;
2947 if (last_run != TIME)
2948 {
2949 last_run = TIME;
2950 tbf_run_timer();
2951 }
2952 }
2953
2954 /* Handle timeouts. Make sure that this gets run anyway, even if there was
2955 * something to read, else under load this will never actually run....
2956 *
2957 */
2958 if (config->cluster_iam_master && next_clean <= time_now)
2959 {
2960 if (regular_cleanups())
2961 {
2962 // Did it finish?
2963 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
2964 }
2965 else
2966 {
2967 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
2968 }
2969 }
2970 }
2971
2972 // Are we the master and shutting down??
2973 if (config->cluster_iam_master)
2974 cluster_heartbeat(); // Flush any queued changes..
2975
2976 // Ok. Notify everyone we're shutting down. If we're
2977 // the master, this will force an election.
2978 cluster_send_ping(0);
2979
2980 //
2981 // Important!!! We MUST not process any packets past this point!
2982 }
2983
2984 static void stripdomain(char *host)
2985 {
2986 char *p;
2987
2988 if ((p = strchr(host, '.')))
2989 {
2990 char *domain = 0;
2991 char _domain[1024];
2992
2993 // strip off domain
2994 FILE *resolv = fopen("/etc/resolv.conf", "r");
2995 if (resolv)
2996 {
2997 char buf[1024];
2998 char *b;
2999
3000 while (fgets(buf, sizeof(buf), resolv))
3001 {
3002 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3003 continue;
3004
3005 if (!isspace(buf[6]))
3006 continue;
3007
3008 b = buf + 7;
3009 while (isspace(*b)) b++;
3010
3011 if (*b)
3012 {
3013 char *d = b;
3014 while (*b && !isspace(*b)) b++;
3015 *b = 0;
3016 if (buf[0] == 'd') // domain is canonical
3017 {
3018 domain = d;
3019 break;
3020 }
3021
3022 // first search line
3023 if (!domain)
3024 {
3025 // hold, may be subsequent domain line
3026 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3027 domain = _domain;
3028 }
3029 }
3030 }
3031
3032 fclose(resolv);
3033 }
3034
3035 if (domain)
3036 {
3037 int hl = strlen(host);
3038 int dl = strlen(domain);
3039 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3040 host[hl -dl - 1] = 0;
3041 }
3042 else
3043 {
3044 *p = 0; // everything after first dot
3045 }
3046 }
3047 }
3048
3049 // Init data structures
3050 static void initdata(int optdebug, char *optconfig)
3051 {
3052 int i;
3053
3054 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3055 {
3056 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3057 exit(1);
3058 }
3059 if (!(config = shared_malloc(sizeof(configt))))
3060 {
3061 LOG(0, 0, 0, "Error doing malloc for configuration: %s\n", strerror(errno));
3062 exit(1);
3063 }
3064 memset(config, 0, sizeof(configt));
3065 time(&config->start_time);
3066 strncpy(config->config_file, optconfig, strlen(optconfig));
3067 config->debug = optdebug;
3068 config->num_tbfs = MAXTBFS;
3069 config->rl_rate = 28; // 28kbps
3070 strcpy(config->random_device, RANDOMDEVICE);
3071
3072 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3073 {
3074 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3075 exit(1);
3076 }
3077 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3078 {
3079 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3080 exit(1);
3081 }
3082
3083 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3084 {
3085 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3086 exit(1);
3087 }
3088
3089 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3090 {
3091 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3092 exit(1);
3093 }
3094
3095 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3096 {
3097 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3098 exit(1);
3099 }
3100
3101 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3102 {
3103 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3104 exit(1);
3105 }
3106 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3107
3108 #ifdef RINGBUFFER
3109 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3110 {
3111 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3112 exit(1);
3113 }
3114 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3115 #endif
3116
3117 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3118 {
3119 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3120 exit(1);
3121 }
3122 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3123
3124 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3125 {
3126 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3127 exit(1);
3128 }
3129 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3130
3131 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3132 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3133 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3134 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3135
3136 // Put all the sessions on the free list marked as undefined.
3137 for (i = 1; i < MAXSESSION; i++)
3138 {
3139 session[i].next = i + 1;
3140 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3141 }
3142 session[MAXSESSION - 1].next = 0;
3143 sessionfree = 1;
3144
3145 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3146 for (i = 1; i < MAXTUNNEL; i++)
3147 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3148
3149 if (!*hostname)
3150 {
3151 // Grab my hostname unless it's been specified
3152 gethostname(hostname, sizeof(hostname));
3153 stripdomain(hostname);
3154 }
3155
3156 _statistics->start_time = _statistics->last_reset = time(NULL);
3157
3158 #ifdef BGP
3159 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3160 {
3161 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3162 exit(1);
3163 }
3164 #endif /* BGP */
3165 }
3166
3167 static int assign_ip_address(sessionidt s)
3168 {
3169 uint32_t i;
3170 int best = -1;
3171 time_t best_time = time_now;
3172 char *u = session[s].user;
3173 char reuse = 0;
3174
3175
3176 CSTAT(assign_ip_address);
3177
3178 for (i = 1; i < ip_pool_size; i++)
3179 {
3180 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3181 continue;
3182
3183 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3184 {
3185 best = i;
3186 reuse = 1;
3187 break;
3188 }
3189
3190 if (ip_address_pool[i].last < best_time)
3191 {
3192 best = i;
3193 if (!(best_time = ip_address_pool[i].last))
3194 break; // never used, grab this one
3195 }
3196 }
3197
3198 if (best < 0)
3199 {
3200 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3201 return 0;
3202 }
3203
3204 session[s].ip = ip_address_pool[best].address;
3205 session[s].ip_pool_index = best;
3206 ip_address_pool[best].assigned = 1;
3207 ip_address_pool[best].last = time_now;
3208 ip_address_pool[best].session = s;
3209 if (session[s].walled_garden)
3210 /* Don't track addresses of users in walled garden (note: this
3211 means that their address isn't "sticky" even if they get
3212 un-gardened). */
3213 ip_address_pool[best].user[0] = 0;
3214 else
3215 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3216
3217 STAT(ip_allocated);
3218 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3219 reuse ? "Reusing" : "Allocating", best);
3220
3221 return 1;
3222 }
3223
3224 static void free_ip_address(sessionidt s)
3225 {
3226 int i = session[s].ip_pool_index;
3227
3228
3229 CSTAT(free_ip_address);
3230
3231 if (!session[s].ip)
3232 return; // what the?
3233
3234 if (i < 0) // Is this actually part of the ip pool?
3235 i = 0;
3236
3237 STAT(ip_freed);
3238 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3239 session[s].ip = 0;
3240 ip_address_pool[i].assigned = 0;
3241 ip_address_pool[i].session = 0;
3242 ip_address_pool[i].last = time_now;
3243 }
3244
3245 //
3246 // Fsck the address pool against the session table.
3247 // Normally only called when we become a master.
3248 //
3249 // This isn't perfect: We aren't keep tracking of which
3250 // users used to have an IP address.
3251 //
3252 void rebuild_address_pool(void)
3253 {
3254 int i;
3255
3256 //
3257 // Zero the IP pool allocation, and build
3258 // a map from IP address to pool index.
3259 for (i = 1; i < MAXIPPOOL; ++i)
3260 {
3261 ip_address_pool[i].assigned = 0;
3262 ip_address_pool[i].session = 0;
3263 if (!ip_address_pool[i].address)
3264 continue;
3265
3266 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3267 }
3268
3269 for (i = 0; i < MAXSESSION; ++i)
3270 {
3271 int ipid;
3272 if (!session[i].ip || !session[i].tunnel)
3273 continue;
3274 ipid = - lookup_ipmap(htonl(session[i].ip));
3275
3276 if (session[i].ip_pool_index < 0)
3277 {
3278 // Not allocated out of the pool.
3279 if (ipid < 1) // Not found in the pool either? good.
3280 continue;
3281
3282 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3283 i, fmtaddr(session[i].ip, 0), ipid);
3284
3285 // Fall through and process it as part of the pool.
3286 }
3287
3288
3289 if (ipid > MAXIPPOOL || ipid < 0)
3290 {
3291 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3292 ipid = -1;
3293 session[i].ip_pool_index = ipid;
3294 continue;
3295 }
3296
3297 ip_address_pool[ipid].assigned = 1;
3298 ip_address_pool[ipid].session = i;
3299 ip_address_pool[ipid].last = time_now;
3300 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3301 session[i].ip_pool_index = ipid;
3302 cache_ipmap(session[i].ip, i); // Fix the ip map.
3303 }
3304 }
3305
3306 //
3307 // Fix the address pool to match a changed session.
3308 // (usually when the master sends us an update).
3309 static void fix_address_pool(int sid)
3310 {
3311 int ipid;
3312
3313 ipid = session[sid].ip_pool_index;
3314
3315 if (ipid > ip_pool_size)
3316 return; // Ignore it. rebuild_address_pool will fix it up.
3317
3318 if (ip_address_pool[ipid].address != session[sid].ip)
3319 return; // Just ignore it. rebuild_address_pool will take care of it.
3320
3321 ip_address_pool[ipid].assigned = 1;
3322 ip_address_pool[ipid].session = sid;
3323 ip_address_pool[ipid].last = time_now;
3324 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3325 }
3326
3327 //
3328 // Add a block of addresses to the IP pool to hand out.
3329 //
3330 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3331 {
3332 int i;
3333 if (mask == 0)
3334 mask = 0xffffffff; // Host route only.
3335
3336 addr &= mask;
3337
3338 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3339 return ;
3340
3341 for (i = addr ;(i & mask) == addr; ++i)
3342 {
3343 if ((i & 0xff) == 0 || (i&0xff) == 255)
3344 continue; // Skip 0 and broadcast addresses.
3345
3346 ip_address_pool[ip_pool_size].address = i;
3347 ip_address_pool[ip_pool_size].assigned = 0;
3348 ++ip_pool_size;
3349 if (ip_pool_size >= MAXIPPOOL)
3350 {
3351 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3352 return;
3353 }
3354 }
3355 }
3356
3357 // Initialize the IP address pool
3358 static void initippool()
3359 {
3360 FILE *f;
3361 char *p;
3362 char buf[4096];
3363 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3364
3365 if (!(f = fopen(IPPOOLFILE, "r")))
3366 {
3367 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3368 exit(1);
3369 }
3370
3371 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3372 {
3373 char *pool = buf;
3374 buf[4095] = 0; // Force it to be zero terminated/
3375
3376 if (*buf == '#' || *buf == '\n')
3377 continue; // Skip comments / blank lines
3378 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3379 if ((p = (char *)strchr(buf, ':')))
3380 {
3381 in_addr_t src;
3382 *p = '\0';
3383 src = inet_addr(buf);
3384 if (src == INADDR_NONE)
3385 {
3386 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3387 exit(1);
3388 }
3389 // This entry is for a specific IP only
3390 if (src != config->bind_address)
3391 continue;
3392 *p = ':';
3393 pool = p+1;
3394 }
3395 if ((p = (char *)strchr(pool, '/')))
3396 {
3397 // It's a range
3398 int numbits = 0;
3399 in_addr_t start = 0, mask = 0;
3400
3401 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3402 *p++ = 0;
3403 if (!*p || !(numbits = atoi(p)))
3404 {
3405 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3406 continue;
3407 }
3408 start = ntohl(inet_addr(pool));
3409 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3410
3411 // Add a static route for this pool
3412 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3413 fmtaddr(htonl(start), 0), 32 + mask);
3414
3415 routeset(0, start, mask, 0, 1);
3416
3417 add_to_ip_pool(start, mask);
3418 }
3419 else
3420 {
3421 // It's a single ip address
3422 add_to_ip_pool(inet_addr(pool), 0);
3423 }
3424 }
3425 fclose(f);
3426 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3427 }
3428
3429 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
3430 {
3431 struct sockaddr_in snoop_addr = {0};
3432 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3433 return;
3434
3435 snoop_addr.sin_family = AF_INET;
3436 snoop_addr.sin_addr.s_addr = destination;
3437 snoop_addr.sin_port = ntohs(port);
3438
3439 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3440 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3441 htons(snoop_addr.sin_port));
3442
3443 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3444 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3445
3446 STAT(packets_snooped);
3447 }
3448
3449 static int dump_session(FILE **f, sessiont *s)
3450 {
3451 if (!s->opened || !s->ip || !(s->cin || s->cout) || !*s->user || s->walled_garden)
3452 return 1;
3453
3454 if (!*f)
3455 {
3456 char filename[1024];
3457 char timestr[64];
3458 time_t now = time(NULL);
3459
3460 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3461 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3462
3463 if (!(*f = fopen(filename, "w")))
3464 {
3465 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3466 return 0;
3467 }
3468
3469 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3470 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3471 "# host: %s\n"
3472 "# time: %ld\n"
3473 "# uptime: %ld\n"
3474 "# format: username ip qos uptxoctets downrxoctets\n",
3475 hostname,
3476 now,
3477 now - basetime);
3478 }
3479
3480 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3481 fprintf(*f, "%s %s %d %u %u\n",
3482 s->user, // username
3483 fmtaddr(htonl(s->ip), 0), // ip
3484 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3485 (uint32_t) s->cin, // uptxoctets
3486 (uint32_t) s->cout); // downrxoctets
3487
3488 s->pin = s->cin = 0;
3489 s->pout = s->cout = 0;
3490
3491 return 1;
3492 }
3493
3494 static void dump_acct_info(int all)
3495 {
3496 int i;
3497 FILE *f = NULL;
3498
3499
3500 CSTAT(dump_acct_info);
3501
3502 if (shut_acct_n)
3503 {
3504 for (i = 0; i < shut_acct_n; i++)
3505 dump_session(&f, &shut_acct[i]);
3506
3507 shut_acct_n = 0;
3508 }
3509
3510 if (all)
3511 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3512 dump_session(&f, &session[i]);
3513
3514 if (f)
3515 fclose(f);
3516 }
3517
3518 // Main program
3519 int main(int argc, char *argv[])
3520 {
3521 int i;
3522 int optdebug = 0;
3523 char *optconfig = CONFIGFILE;
3524
3525 time(&basetime); // start clock
3526
3527 // scan args
3528 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3529 {
3530 switch (i)
3531 {
3532 case 'd':
3533 if (fork()) exit(0);
3534 setsid();
3535 freopen("/dev/null", "r", stdin);
3536 freopen("/dev/null", "w", stdout);
3537 freopen("/dev/null", "w", stderr);
3538 break;
3539 case 'v':
3540 optdebug++;
3541 break;
3542 case 'c':
3543 optconfig = optarg;
3544 break;
3545 case 'h':
3546 snprintf(hostname, sizeof(hostname), "%s", optarg);
3547 break;
3548 default:
3549 printf("Args are:\n"
3550 "\t-d\t\tDetach from terminal\n"
3551 "\t-c <file>\tConfig file\n"
3552 "\t-h <hostname>\tForce hostname\n"
3553 "\t-v\t\tDebug\n");
3554
3555 return (0);
3556 break;
3557 }
3558 }
3559
3560 // Start the timer routine off
3561 time(&time_now);
3562 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3563 signal(SIGALRM, sigalrm_handler);
3564 siginterrupt(SIGALRM, 0);
3565
3566 initplugins();
3567 initdata(optdebug, optconfig);
3568
3569 init_cli(hostname);
3570 read_config_file();
3571 init_tbf(config->num_tbfs);
3572
3573 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3574 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3575 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3576 {
3577 struct rlimit rlim;
3578 rlim.rlim_cur = RLIM_INFINITY;
3579 rlim.rlim_max = RLIM_INFINITY;
3580 // Remove the maximum core size
3581 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3582 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3583
3584 // Make core dumps go to /tmp
3585 chdir("/tmp");
3586 }
3587
3588 if (config->scheduler_fifo)
3589 {
3590 int ret;
3591 struct sched_param params = {0};
3592 params.sched_priority = 1;
3593
3594 if (get_nprocs() < 2)
3595 {
3596 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3597 config->scheduler_fifo = 0;
3598 }
3599 else
3600 {
3601 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3602 {
3603 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3604 }
3605 else
3606 {
3607 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3608 config->scheduler_fifo = 0;
3609 }
3610 }
3611 }
3612
3613 /* Set up the cluster communications port. */
3614 if (cluster_init() < 0)
3615 exit(1);
3616
3617 #ifdef BGP
3618 signal(SIGPIPE, SIG_IGN);
3619 bgp_setup(config->as_number);
3620 bgp_add_route(config->bind_address, 0xffffffff);
3621 for (i = 0; i < BGP_NUM_PEERS; i++)
3622 {
3623 if (config->neighbour[i].name[0])
3624 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3625 config->neighbour[i].as, config->neighbour[i].keepalive,
3626 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3627 }
3628 #endif /* BGP */
3629
3630 inittun();
3631 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3632
3633 initudp();
3634 initrad();
3635 initippool();
3636
3637 signal(SIGHUP, sighup_handler);
3638 signal(SIGTERM, sigterm_handler);
3639 signal(SIGINT, sigterm_handler);
3640 signal(SIGQUIT, sigquit_handler);
3641 signal(SIGCHLD, sigchild_handler);
3642
3643 // Prevent us from getting paged out
3644 if (config->lock_pages)
3645 {
3646 if (!mlockall(MCL_CURRENT))
3647 LOG(1, 0, 0, "Locking pages into memory\n");
3648 else
3649 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3650 }
3651
3652 alarm(1);
3653
3654 // Drop privileges here
3655 if (config->target_uid > 0 && geteuid() == 0)
3656 setuid(config->target_uid);
3657
3658 mainloop();
3659
3660 #ifdef BGP
3661 /* try to shut BGP down cleanly; with luck the sockets will be
3662 writable since we're out of the select */
3663 for (i = 0; i < BGP_NUM_PEERS; i++)
3664 if (bgp_peers[i].state == Established)
3665 bgp_stop(&bgp_peers[i]);
3666 #endif /* BGP */
3667
3668 /* remove plugins (so cleanup code gets run) */
3669 plugins_done();
3670
3671 // Remove the PID file if we wrote it
3672 if (config->wrote_pid && *config->pid_file == '/')
3673 unlink(config->pid_file);
3674
3675 /* kill CLI children */
3676 signal(SIGTERM, SIG_IGN);
3677 kill(0, SIGTERM);
3678 return 0;
3679 }
3680
3681 static void sighup_handler(int sig)
3682 {
3683 if (log_stream && log_stream != stderr)
3684 {
3685 fclose(log_stream);
3686 log_stream = NULL;
3687 }
3688
3689 read_config_file();
3690 }
3691
3692 static void sigalrm_handler(int sig)
3693 {
3694 // Log current traffic stats
3695
3696 snprintf(config->bandwidth, sizeof(config->bandwidth),
3697 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3698 (udp_rx / 1024.0 / 1024.0 * 8),
3699 (eth_tx / 1024.0 / 1024.0 * 8),
3700 (eth_rx / 1024.0 / 1024.0 * 8),
3701 (udp_tx / 1024.0 / 1024.0 * 8),
3702 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3703 udp_rx_pkt, eth_rx_pkt);
3704
3705 udp_tx = udp_rx = 0;
3706 udp_rx_pkt = eth_rx_pkt = 0;
3707 eth_tx = eth_rx = 0;
3708
3709 if (config->dump_speed)
3710 printf("%s\n", config->bandwidth);
3711
3712 // Update the internal time counter
3713 time(&time_now);
3714 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3715 alarm(1);
3716
3717 {
3718 // Run timer hooks
3719 struct param_timer p = { time_now };
3720 run_plugins(PLUGIN_TIMER, &p);
3721 }
3722
3723 }
3724
3725 static void sigterm_handler(int sig)
3726 {
3727 LOG(1, 0, 0, "Shutting down cleanly\n");
3728 main_quit++;
3729 }
3730
3731 static void sigquit_handler(int sig)
3732 {
3733 int i;
3734
3735 LOG(1, 0, 0, "Shutting down without saving sessions\n");
3736
3737 if (config->cluster_iam_master)
3738 {
3739 for (i = 1; i < MAXSESSION; i++)
3740 {
3741 if (session[i].opened)
3742 sessionkill(i, "L2TPNS Closing");
3743 }
3744 for (i = 1; i < MAXTUNNEL; i++)
3745 {
3746 if (tunnel[i].ip || tunnel[i].state)
3747 tunnelshutdown(i, "L2TPNS Closing");
3748 }
3749 }
3750
3751 main_quit++;
3752 }
3753
3754 static void sigchild_handler(int sig)
3755 {
3756 while (waitpid(-1, NULL, WNOHANG) > 0)
3757 ;
3758 }
3759
3760 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
3761 {
3762 MD5_CTX ctx;
3763 *challenge_response = NULL;
3764
3765 if (!*config->l2tpsecret)
3766 {
3767 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3768 return;
3769 }
3770
3771 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
3772
3773 *challenge_response = (char *)calloc(17, 1);
3774
3775 MD5Init(&ctx);
3776 MD5Update(&ctx, &id, 1);
3777 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3778 MD5Update(&ctx, challenge, challenge_length);
3779 MD5Final(*challenge_response, &ctx);
3780
3781 return;
3782 }
3783
3784 static int facility_value(char *name)
3785 {
3786 int i;
3787 for (i = 0; facilitynames[i].c_name; i++)
3788 {
3789 if (strcmp(facilitynames[i].c_name, name) == 0)
3790 return facilitynames[i].c_val;
3791 }
3792 return 0;
3793 }
3794
3795 static void update_config()
3796 {
3797 int i;
3798 char *p;
3799 static int timeout = 0;
3800 static int interval = 0;
3801
3802 // Update logging
3803 closelog();
3804 syslog_log = 0;
3805 if (log_stream)
3806 {
3807 fclose(log_stream);
3808 log_stream = NULL;
3809 }
3810
3811 if (*config->log_filename)
3812 {
3813 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3814 {
3815 char *p = config->log_filename + 7;
3816 if (*p)
3817 {
3818 openlog("l2tpns", LOG_PID, facility_value(p));
3819 syslog_log = 1;
3820 }
3821 }
3822 else if (strchr(config->log_filename, '/') == config->log_filename)
3823 {
3824 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3825 {
3826 fseek(log_stream, 0, SEEK_END);
3827 setbuf(log_stream, NULL);
3828 }
3829 else
3830 {
3831 log_stream = stderr;
3832 setbuf(log_stream, NULL);
3833 }
3834 }
3835 }
3836 else
3837 {
3838 log_stream = stderr;
3839 setbuf(log_stream, NULL);
3840 }
3841
3842 // Update radius
3843 config->numradiusservers = 0;
3844 for (i = 0; i < MAXRADSERVER; i++)
3845 if (config->radiusserver[i])
3846 {
3847 config->numradiusservers++;
3848 // Set radius port: if not set, take the port from the
3849 // first radius server. For the first radius server,
3850 // take the #defined default value from l2tpns.h
3851
3852 // test twice, In case someone works with
3853 // a secondary radius server without defining
3854 // a primary one, this will work even then.
3855 if (i>0 && !config->radiusport[i])
3856 config->radiusport[i] = config->radiusport[i-1];
3857 if (!config->radiusport[i])
3858 config->radiusport[i] = RADPORT;
3859 }
3860
3861 if (!config->numradiusservers)
3862 LOG(0, 0, 0, "No RADIUS servers defined!\n");
3863
3864 config->num_radfds = 2 << RADIUS_SHIFT;
3865
3866 // parse radius_authtypes_s
3867 config->radius_authtypes = config->radius_authprefer = 0;
3868 p = config->radius_authtypes_s;
3869 while (*p)
3870 {
3871 char *s = strpbrk(p, " \t,");
3872 int type = 0;
3873
3874 if (s)
3875 {
3876 *s++ = 0;
3877 while (*s == ' ' || *s == '\t')
3878 s++;
3879
3880 if (!*s)
3881 s = 0;
3882 }
3883
3884 if (!strncasecmp("chap", p, strlen(p)))
3885 type = AUTHCHAP;
3886 else if (!strncasecmp("pap", p, strlen(p)))
3887 type = AUTHPAP;
3888 else
3889 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"", p);
3890
3891 config->radius_authtypes |= type;
3892 if (!config->radius_authprefer)
3893 config->radius_authprefer = type;
3894 }
3895
3896 if (!config->radius_authtypes)
3897 {
3898 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
3899 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
3900 }
3901
3902 // normalise radius_authtypes_s
3903 if (config->radius_authprefer == AUTHPAP)
3904 {
3905 strcpy(config->radius_authtypes_s, "pap");
3906 if (config->radius_authtypes & AUTHCHAP)
3907 strcat(config->radius_authtypes_s, ", chap");
3908 }
3909 else
3910 {
3911 strcpy(config->radius_authtypes_s, "chap");
3912 if (config->radius_authtypes & AUTHPAP)
3913 strcat(config->radius_authtypes_s, ", pap");
3914 }
3915
3916 // re-initialise the random number source
3917 initrandom(config->random_device);
3918
3919 // Update plugins
3920 for (i = 0; i < MAXPLUGINS; i++)
3921 {
3922 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
3923 continue;
3924
3925 if (*config->plugins[i])
3926 {
3927 // Plugin added
3928 add_plugin(config->plugins[i]);
3929 }
3930 else if (*config->old_plugins[i])
3931 {
3932 // Plugin removed
3933 remove_plugin(config->old_plugins[i]);
3934 }
3935 }
3936
3937 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
3938 if (!config->cleanup_interval) config->cleanup_interval = 10;
3939 if (!config->multi_read_count) config->multi_read_count = 10;
3940 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
3941 if (!*config->cluster_interface)
3942 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
3943
3944 if (!config->cluster_hb_interval)
3945 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
3946
3947 if (!config->cluster_hb_timeout)
3948 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
3949
3950 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
3951 {
3952 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
3953 // late, ensure we're sufficiently larger than that
3954 int t = 4 * config->cluster_hb_interval + 11;
3955
3956 if (config->cluster_hb_timeout < t)
3957 {
3958 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
3959 config->cluster_hb_timeout = t;
3960 }
3961
3962 // Push timing changes to the slaves immediately if we're the master
3963 if (config->cluster_iam_master)
3964 cluster_heartbeat();
3965
3966 interval = config->cluster_hb_interval;
3967 timeout = config->cluster_hb_timeout;
3968 }
3969
3970 // Write PID file
3971 if (*config->pid_file == '/' && !config->wrote_pid)
3972 {
3973 FILE *f;
3974 if ((f = fopen(config->pid_file, "w")))
3975 {
3976 fprintf(f, "%d\n", getpid());
3977 fclose(f);
3978 config->wrote_pid = 1;
3979 }
3980 else
3981 {
3982 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
3983 }
3984 }
3985
3986 config->reload_config = 0;
3987 }
3988
3989 static void read_config_file()
3990 {
3991 FILE *f;
3992
3993 if (!config->config_file) return;
3994 if (!(f = fopen(config->config_file, "r")))
3995 {
3996 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
3997 return;
3998 }
3999
4000 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4001 cli_do_file(f);
4002 LOG(3, 0, 0, "Done reading config file\n");
4003 fclose(f);
4004 update_config();
4005 }
4006
4007 int sessionsetup(tunnelidt t, sessionidt s)
4008 {
4009 // A session now exists, set it up
4010 in_addr_t ip;
4011 char *user;
4012 sessionidt i;
4013 int r;
4014
4015 CSTAT(sessionsetup);
4016
4017 LOG(3, s, t, "Doing session setup for session\n");
4018
4019 if (!session[s].ip || session[s].ip == 0xFFFFFFFE)
4020 {
4021 assign_ip_address(s);
4022 if (!session[s].ip)
4023 {
4024 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4025 sessionshutdown(s, "No IP addresses available");
4026 return 0;
4027 }
4028 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4029 fmtaddr(htonl(session[s].ip), 0));
4030 }
4031
4032
4033 // Make sure this is right
4034 session[s].tunnel = t;
4035
4036 // zap old sessions with same IP and/or username
4037 // Don't kill gardened sessions - doing so leads to a DoS
4038 // from someone who doesn't need to know the password
4039 {
4040 ip = session[s].ip;
4041 user = session[s].user;
4042 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4043 {
4044 if (i == s) continue;
4045 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
4046 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
4047 sessionkill(i, "Duplicate session for users");
4048 }
4049 }
4050
4051 {
4052 int routed = 0;
4053
4054 // Add the route for this session.
4055 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4056 {
4057 if ((session[s].ip & session[s].route[r].mask) ==
4058 (session[s].route[r].ip & session[s].route[r].mask))
4059 routed++;
4060
4061 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4062 }
4063
4064 // Static IPs need to be routed if not already
4065 // convered by a Framed-Route. Anything else is part
4066 // of the IP address pool and is already routed, it
4067 // just needs to be added to the IP cache.
4068 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4069 if (session[s].ip_pool_index == -1) // static ip
4070 {
4071 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4072 }
4073 else
4074 cache_ipmap(session[s].ip, s);
4075 }
4076
4077 if (!session[s].unique_id)
4078 {
4079 // did this session just finish radius?
4080 LOG(3, s, t, "Sending initial IPCP to client\n");
4081 sendipcp(t, s);
4082 session[s].unique_id = ++last_id;
4083 }
4084
4085 // Run the plugin's against this new session.
4086 {
4087 struct param_new_session data = { &tunnel[t], &session[s] };
4088 run_plugins(PLUGIN_NEW_SESSION, &data);
4089 }
4090
4091 // Allocate TBFs if throttled
4092 if (session[s].throttle_in || session[s].throttle_out)
4093 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4094
4095 session[s].last_packet = time_now;
4096
4097 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4098 fmtaddr(htonl(session[s].ip), 0),
4099 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4100
4101 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4102
4103 return 1; // RADIUS OK and IP allocated, done...
4104 }
4105
4106 //
4107 // This session just got dropped on us by the master or something.
4108 // Make sure our tables up up to date...
4109 //
4110 int load_session(sessionidt s, sessiont *new)
4111 {
4112 int i;
4113 int newip = 0;
4114
4115 // Sanity checks.
4116 if (new->ip_pool_index >= MAXIPPOOL ||
4117 new->tunnel >= MAXTUNNEL)
4118 {
4119 LOG(0, s, 0, "Strange session update received!\n");
4120 // FIXME! What to do here?
4121 return 0;
4122 }
4123
4124 //
4125 // Ok. All sanity checks passed. Now we're committed to
4126 // loading the new session.
4127 //
4128
4129 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4130
4131 // See if routes/ip cache need updating
4132 if (new->ip != session[s].ip)
4133 newip++;
4134
4135 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4136 if (new->route[i].ip != session[s].route[i].ip ||
4137 new->route[i].mask != session[s].route[i].mask)
4138 newip++;
4139
4140 // needs update
4141 if (newip)
4142 {
4143 int routed = 0;
4144
4145 // remove old routes...
4146 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4147 {
4148 if ((session[s].ip & session[s].route[i].mask) ==
4149 (session[s].route[i].ip & session[s].route[i].mask))
4150 routed++;
4151
4152 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4153 }
4154
4155 // ...ip
4156 if (session[s].ip)
4157 {
4158 if (session[s].ip_pool_index == -1) // static IP
4159 {
4160 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4161 }
4162 else // It's part of the IP pool, remove it manually.
4163 uncache_ipmap(session[s].ip);
4164 }
4165
4166 routed = 0;
4167
4168 // add new routes...
4169 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4170 {
4171 if ((new->ip & new->route[i].mask) ==
4172 (new->route[i].ip & new->route[i].mask))
4173 routed++;
4174
4175 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4176 }
4177
4178 // ...ip
4179 if (new->ip)
4180 {
4181 // If there's a new one, add it.
4182 if (new->ip_pool_index == -1)
4183 {
4184 if (!routed) routeset(s, new->ip, 0, 0, 1);
4185 }
4186 else
4187 cache_ipmap(new->ip, s);
4188 }
4189 }
4190
4191 // check v6 routing
4192 if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
4193 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4194
4195 // check filters
4196 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4197 {
4198 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4199 new->filter_in = 0;
4200 }
4201
4202 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4203 {
4204 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4205 new->filter_out = 0;
4206 }
4207
4208 if (new->filter_in != session[s].filter_in)
4209 {
4210 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4211 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4212 }
4213
4214 if (new->filter_out != session[s].filter_out)
4215 {
4216 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4217 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4218 }
4219
4220 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4221 // for walking the sessions to forward byte counts to the master.
4222 config->cluster_highest_sessionid = s;
4223
4224 // TEMP: old session struct used a uint32_t to define the throttle
4225 // speed for both up/down, new uses a uint16_t for each. Deal with
4226 // sessions from an old master for migration.
4227 if (new->throttle_out == 0 && new->tbf_out)
4228 new->throttle_out = new->throttle_in;
4229
4230 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4231
4232 // Do fixups into address pool.
4233 if (new->ip_pool_index != -1)
4234 fix_address_pool(s);
4235
4236 return 1;
4237 }
4238
4239 static void initplugins()
4240 {
4241 int i;
4242
4243 loaded_plugins = ll_init();
4244 // Initialize the plugins to nothing
4245 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4246 plugins[i] = ll_init();
4247 }
4248
4249 static void *open_plugin(char *plugin_name, int load)
4250 {
4251 char path[256] = "";
4252
4253 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4254 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4255 return dlopen(path, RTLD_NOW);
4256 }
4257
4258 // plugin callback to get a config value
4259 static void *getconfig(char *key, enum config_typet type)
4260 {
4261 int i;
4262
4263 for (i = 0; config_values[i].key; i++)
4264 {
4265 if (!strcmp(config_values[i].key, key))
4266 {
4267 if (config_values[i].type == type)
4268 return ((void *) config) + config_values[i].offset;
4269
4270 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4271 key, type, config_values[i].type);
4272
4273 return 0;
4274 }
4275 }
4276
4277 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4278 return 0;
4279 }
4280
4281 static int add_plugin(char *plugin_name)
4282 {
4283 static struct pluginfuncs funcs = {
4284 _log,
4285 _log_hex,
4286 fmtaddr,
4287 sessionbyuser,
4288 sessiontbysessionidt,
4289 sessionidtbysessiont,
4290 radiusnew,
4291 radiussend,
4292 getconfig,
4293 sessionkill,
4294 throttle_session,
4295 cluster_send_session,
4296 };
4297
4298 void *p = open_plugin(plugin_name, 1);
4299 int (*initfunc)(struct pluginfuncs *);
4300 int i;
4301
4302 if (!p)
4303 {
4304 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4305 return -1;
4306 }
4307
4308 if (ll_contains(loaded_plugins, p))
4309 {
4310 dlclose(p);
4311 return 0; // already loaded
4312 }
4313
4314 {
4315 int *v = dlsym(p, "plugin_api_version");
4316 if (!v || *v != PLUGIN_API_VERSION)
4317 {
4318 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4319 dlclose(p);
4320 return -1;
4321 }
4322 }
4323
4324 if ((initfunc = dlsym(p, "plugin_init")))
4325 {
4326 if (!initfunc(&funcs))
4327 {
4328 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4329 dlclose(p);
4330 return -1;
4331 }
4332 }
4333
4334 ll_push(loaded_plugins, p);
4335
4336 for (i = 0; i < max_plugin_functions; i++)
4337 {
4338 void *x;
4339 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4340 {
4341 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4342 ll_push(plugins[i], x);
4343 }
4344 }
4345
4346 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4347 return 1;
4348 }
4349
4350 static void run_plugin_done(void *plugin)
4351 {
4352 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4353
4354 if (donefunc)
4355 donefunc();
4356 }
4357
4358 static int remove_plugin(char *plugin_name)
4359 {
4360 void *p = open_plugin(plugin_name, 0);
4361 int loaded = 0;
4362
4363 if (!p)
4364 return -1;
4365
4366 if (ll_contains(loaded_plugins, p))
4367 {
4368 int i;
4369 for (i = 0; i < max_plugin_functions; i++)
4370 {
4371 void *x;
4372 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4373 ll_delete(plugins[i], x);
4374 }
4375
4376 ll_delete(loaded_plugins, p);
4377 run_plugin_done(p);
4378 loaded = 1;
4379 }
4380
4381 dlclose(p);
4382 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4383 return loaded;
4384 }
4385
4386 int run_plugins(int plugin_type, void *data)
4387 {
4388 int (*func)(void *data);
4389
4390 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4391 return PLUGIN_RET_ERROR;
4392
4393 ll_reset(plugins[plugin_type]);
4394 while ((func = ll_next(plugins[plugin_type])))
4395 {
4396 int r = func(data);
4397
4398 if (r != PLUGIN_RET_OK)
4399 return r; // stop here
4400 }
4401
4402 return PLUGIN_RET_OK;
4403 }
4404
4405 static void plugins_done()
4406 {
4407 void *p;
4408
4409 ll_reset(loaded_plugins);
4410 while ((p = ll_next(loaded_plugins)))
4411 run_plugin_done(p);
4412 }
4413
4414 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4415 {
4416 struct nsctl request;
4417 struct nsctl response;
4418 int type = unpack_control(&request, buf, len);
4419 int r;
4420 void *p;
4421
4422 if (log_stream && config->debug >= 4)
4423 {
4424 if (type < 0)
4425 {
4426 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4427 fmtaddr(addr->sin_addr.s_addr, 0), type);
4428 }
4429 else
4430 {
4431 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4432 dump_control(&request, log_stream);
4433 }
4434 }
4435
4436 switch (type)
4437 {
4438 case NSCTL_REQ_LOAD:
4439 if (request.argc != 1)
4440 {
4441 response.type = NSCTL_RES_ERR;
4442 response.argc = 1;
4443 response.argv[0] = "name of plugin required";
4444 }
4445 else if ((r = add_plugin(request.argv[0])) < 1)
4446 {
4447 response.type = NSCTL_RES_ERR;
4448 response.argc = 1;
4449 response.argv[0] = !r
4450 ? "plugin already loaded"
4451 : "error loading plugin";
4452 }
4453 else
4454 {
4455 response.type = NSCTL_RES_OK;
4456 response.argc = 0;
4457 }
4458
4459 break;
4460
4461 case NSCTL_REQ_UNLOAD:
4462 if (request.argc != 1)
4463 {
4464 response.type = NSCTL_RES_ERR;
4465 response.argc = 1;
4466 response.argv[0] = "name of plugin required";
4467 }
4468 else if ((r = remove_plugin(request.argv[0])) < 1)
4469 {
4470 response.type = NSCTL_RES_ERR;
4471 response.argc = 1;
4472 response.argv[0] = !r
4473 ? "plugin not loaded"
4474 : "plugin not found";
4475 }
4476 else
4477 {
4478 response.type = NSCTL_RES_OK;
4479 response.argc = 0;
4480 }
4481
4482 break;
4483
4484 case NSCTL_REQ_HELP:
4485 response.type = NSCTL_RES_OK;
4486 response.argc = 0;
4487
4488 ll_reset(loaded_plugins);
4489 while ((p = ll_next(loaded_plugins)))
4490 {
4491 char **help = dlsym(p, "plugin_control_help");
4492 while (response.argc < 0xff && help && *help)
4493 response.argv[response.argc++] = *help++;
4494 }
4495
4496 break;
4497
4498 case NSCTL_REQ_CONTROL:
4499 {
4500 struct param_control param = {
4501 config->cluster_iam_master,
4502 request.argc,
4503 request.argv,
4504 0,
4505 NULL,
4506 };
4507
4508 int r = run_plugins(PLUGIN_CONTROL, &param);
4509
4510 if (r == PLUGIN_RET_ERROR)
4511 {
4512 response.type = NSCTL_RES_ERR;
4513 response.argc = 1;
4514 response.argv[0] = param.additional
4515 ? param.additional
4516 : "error returned by plugin";
4517 }
4518 else if (r == PLUGIN_RET_NOTMASTER)
4519 {
4520 static char msg[] = "must be run on master: 000.000.000.000";
4521
4522 response.type = NSCTL_RES_ERR;
4523 response.argc = 1;
4524 if (config->cluster_master_address)
4525 {
4526 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4527 response.argv[0] = msg;
4528 }
4529 else
4530 {
4531 response.argv[0] = "must be run on master: none elected";
4532 }
4533 }
4534 else if (!(param.response & NSCTL_RESPONSE))
4535 {
4536 response.type = NSCTL_RES_ERR;
4537 response.argc = 1;
4538 response.argv[0] = param.response
4539 ? "unrecognised response value from plugin"
4540 : "unhandled action";
4541 }
4542 else
4543 {
4544 response.type = param.response;
4545 response.argc = 0;
4546 if (param.additional)
4547 {
4548 response.argc = 1;
4549 response.argv[0] = param.additional;
4550 }
4551 }
4552 }
4553
4554 break;
4555
4556 default:
4557 response.type = NSCTL_RES_ERR;
4558 response.argc = 1;
4559 response.argv[0] = "error unpacking control packet";
4560 }
4561
4562 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4563 if (!buf)
4564 {
4565 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4566 return;
4567 }
4568
4569 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4570 if (r > 0)
4571 {
4572 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4573 if (log_stream && config->debug >= 4)
4574 {
4575 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4576 dump_control(&response, log_stream);
4577 }
4578 }
4579 else
4580 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4581 fmtaddr(addr->sin_addr.s_addr, 0), r);
4582
4583 free(buf);
4584 }
4585
4586 static tunnelidt new_tunnel()
4587 {
4588 tunnelidt i;
4589 for (i = 1; i < MAXTUNNEL; i++)
4590 {
4591 if (tunnel[i].state == TUNNELFREE)
4592 {
4593 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4594 if (i > config->cluster_highest_tunnelid)
4595 config->cluster_highest_tunnelid = i;
4596 return i;
4597 }
4598 }
4599 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4600 return 0;
4601 }
4602
4603 //
4604 // We're becoming the master. Do any required setup..
4605 //
4606 // This is principally telling all the plugins that we're
4607 // now a master, and telling them about all the sessions
4608 // that are active too..
4609 //
4610 void become_master(void)
4611 {
4612 int s, i;
4613 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4614
4615 // running a bunch of iptables commands is slow and can cause
4616 // the master to drop tunnels on takeover--kludge around the
4617 // problem by forking for the moment (note: race)
4618 if (!fork_and_close())
4619 {
4620 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4621 {
4622 if (!session[s].tunnel) // Not an in-use session.
4623 continue;
4624
4625 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4626 }
4627 exit(0);
4628 }
4629
4630 // add radius fds
4631 for (i = 0; i < config->num_radfds; i++)
4632 {
4633 FD_SET(radfds[i], &readset);
4634 if (radfds[i] > readset_n)
4635 readset_n = radfds[i];
4636 }
4637 }
4638
4639 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4640 {
4641 int s, i;
4642 int count = 0;
4643 int buckets[64];
4644
4645 if (CLI_HELP_REQUESTED)
4646 return CLI_HELP_NO_ARGS;
4647
4648 time(&time_now);
4649 for (i = 0; i < 64;++i) buckets[i] = 0;
4650
4651 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4652 {
4653 int idle;
4654 if (!session[s].tunnel)
4655 continue;
4656
4657 idle = time_now - session[s].last_packet;
4658 idle /= 5 ; // In multiples of 5 seconds.
4659 if (idle < 0)
4660 idle = 0;
4661 if (idle > 63)
4662 idle = 63;
4663
4664 ++count;
4665 ++buckets[idle];
4666 }
4667
4668 for (i = 0; i < 63; ++i)
4669 {
4670 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4671 }
4672 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4673 cli_print(cli, "%d total sessions open.", count);
4674 return CLI_OK;
4675 }
4676
4677 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4678 {
4679 int s, i;
4680 int count = 0;
4681 int buckets[64];
4682
4683 if (CLI_HELP_REQUESTED)
4684 return CLI_HELP_NO_ARGS;
4685
4686 time(&time_now);
4687 for (i = 0; i < 64;++i) buckets[i] = 0;
4688
4689 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4690 {
4691 int open = 0, d;
4692 if (!session[s].tunnel)
4693 continue;
4694
4695 d = time_now - session[s].opened;
4696 if (d < 0)
4697 d = 0;
4698 while (d > 1 && open < 32)
4699 {
4700 ++open;
4701 d >>= 1; // half.
4702 }
4703 ++count;
4704 ++buckets[open];
4705 }
4706
4707 s = 1;
4708 for (i = 0; i < 30; ++i)
4709 {
4710 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4711 s <<= 1;
4712 }
4713 cli_print(cli, "%d total sessions open.", count);
4714 return CLI_OK;
4715 }
4716
4717 /* Unhide an avp.
4718 *
4719 * This unencodes the AVP using the L2TP CHAP secret and the
4720 * previously stored random vector. It replaces the hidden data with
4721 * the cleartext data and returns the length of the cleartext data
4722 * (including the AVP "header" of 6 bytes).
4723 *
4724 * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
4725 */
4726 static int unhide_avp(uint8_t *avp, tunnelidt t, sessionidt s, uint16_t length)
4727 {
4728 MD5_CTX ctx;
4729 uint8_t *cursor;
4730 uint8_t digest[16];
4731 uint8_t working_vector[16];
4732 uint16_t hidden_length;
4733 uint8_t type[2];
4734 size_t done, todo;
4735 uint8_t *output;
4736
4737 // Find the AVP type.
4738 type[0] = *(avp + 4);
4739 type[1] = *(avp + 5);
4740
4741 // Line up with the hidden data
4742 cursor = output = avp + 6;
4743
4744 // Compute initial pad
4745 MD5Init(&ctx);
4746 MD5Update(&ctx, type, 2);
4747 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4748 MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
4749 MD5Final(digest, &ctx);
4750
4751 // Get hidden length
4752 hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
4753
4754 // Keep these for later use
4755 working_vector[0] = *cursor;
4756 working_vector[1] = *(cursor + 1);
4757 cursor += 2;
4758
4759 if (hidden_length > length - 8)
4760 {
4761 LOG(1, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
4762 return 0;
4763 }
4764
4765 /* Decrypt remainder */
4766 done = 2;
4767 todo = hidden_length;
4768 while (todo)
4769 {
4770 working_vector[done] = *cursor;
4771 *output = digest[done] ^ *cursor;
4772 ++output;
4773 ++cursor;
4774 --todo;
4775 ++done;
4776 if (done == 16 && todo)
4777 {
4778 // Compute new digest
4779 done = 0;
4780 MD5Init(&ctx);
4781 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4782 MD5Update(&ctx, &working_vector, 16);
4783 MD5Final(digest, &ctx);
4784 }
4785 }
4786
4787 return hidden_length + 6;
4788 }
4789
4790 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
4791 {
4792 switch (p->op)
4793 {
4794 case FILTER_PORT_OP_EQ: return port == p->port;
4795 case FILTER_PORT_OP_NEQ: return port != p->port;
4796 case FILTER_PORT_OP_GT: return port > p->port;
4797 case FILTER_PORT_OP_LT: return port < p->port;
4798 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
4799 }
4800
4801 return 0;
4802 }
4803
4804 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
4805 {
4806 switch (op)
4807 {
4808 case FILTER_FLAG_OP_ANY:
4809 return (flags & sflags) || (~flags & cflags);
4810
4811 case FILTER_FLAG_OP_ALL:
4812 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
4813
4814 case FILTER_FLAG_OP_EST:
4815 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
4816 }
4817
4818 return 0;
4819 }
4820
4821 int ip_filter(uint8_t *buf, int len, uint8_t filter)
4822 {
4823 uint16_t frag_offset;
4824 uint8_t proto;
4825 in_addr_t src_ip;
4826 in_addr_t dst_ip;
4827 uint16_t src_port = 0;
4828 uint16_t dst_port = 0;
4829 uint8_t flags = 0;
4830 ip_filter_rulet *rule;
4831
4832 if (len < 20) // up to end of destination address
4833 return 0;
4834
4835 if ((*buf >> 4) != 4) // IPv4
4836 return 0;
4837
4838 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
4839 proto = buf[9];
4840 src_ip = *(in_addr_t *) (buf + 12);
4841 dst_ip = *(in_addr_t *) (buf + 16);
4842
4843 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
4844 {
4845 int l = (buf[0] & 0xf) * 4; // length of IP header
4846 if (len < l + 4) // ports
4847 return 0;
4848
4849 src_port = ntohs(*(uint16_t *) (buf + l));
4850 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
4851 if (proto == IPPROTO_TCP)
4852 {
4853 if (len < l + 14) // flags
4854 return 0;
4855
4856 flags = buf[l + 13] & 0x3f;
4857 }
4858 }
4859
4860 for (rule = ip_filters[filter].rules; rule->action; rule++)
4861 {
4862 if (rule->proto != IPPROTO_IP && proto != rule->proto)
4863 continue;
4864
4865 if (rule->src_wild != INADDR_BROADCAST &&
4866 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
4867 continue;
4868
4869 if (rule->dst_wild != INADDR_BROADCAST &&
4870 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
4871 continue;
4872
4873 if (frag_offset)
4874 {
4875 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
4876 continue;
4877 }
4878 else
4879 {
4880 if (rule->frag)
4881 continue;
4882
4883 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
4884 {
4885 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
4886 continue;
4887
4888 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
4889 continue;
4890
4891 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
4892 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
4893 continue;
4894 }
4895 }
4896
4897 // matched
4898 rule->counter++;
4899 return rule->action == FILTER_ACTION_PERMIT;
4900 }
4901
4902 // default deny
4903 return 0;
4904 }