2fa9b12e487dbdc0ec82b5f5560bb7de1f401159
[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 1.104 2005-05-16 04:51:16 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 int syslog_log = 0; // are we logging to syslog
72 static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
73 extern int cluster_sockfd; // Intra-cluster communications socket.
74 uint32_t last_id = 0; // Unique ID for radius accounting
75
76 struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
77 struct cli_tunnel_actions *cli_tunnel_actions = NULL; // Pending tunnel changes required by CLI
78
79 static void *ip_hash[256]; // Mapping from IP address to session structures.
80 struct ipv6radix {
81 int sess;
82 struct ipv6radix *branch;
83 } ipv6_hash[256]; // Mapping from IPv6 address to session structures.
84
85 // Traffic counters.
86 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
87 static uint32_t eth_rx = 0, eth_rx_pkt = 0;
88 uint32_t eth_tx = 0;
89
90 static uint32_t ip_pool_size = 1; // Size of the pool of addresses used for dynamic address allocation.
91 time_t time_now = 0; // Current time in seconds since epoch.
92 static char time_now_string[64] = {0}; // Current time as a string.
93 static char main_quit = 0; // True if we're in the process of exiting.
94 linked_list *loaded_plugins;
95 linked_list *plugins[MAX_PLUGIN_TYPES];
96
97 #define membersize(STRUCT, MEMBER) sizeof(((STRUCT *)0)->MEMBER)
98 #define CONFIG(NAME, MEMBER, TYPE) { NAME, offsetof(configt, MEMBER), membersize(configt, MEMBER), TYPE }
99
100 config_descriptt config_values[] = {
101 CONFIG("debug", debug, INT),
102 CONFIG("log_file", log_filename, STRING),
103 CONFIG("pid_file", pid_file, STRING),
104 CONFIG("random_device", random_device, STRING),
105 CONFIG("l2tp_secret", l2tpsecret, STRING),
106 CONFIG("primary_dns", default_dns1, IPv4),
107 CONFIG("secondary_dns", default_dns2, IPv4),
108 CONFIG("primary_radius", radiusserver[0], IPv4),
109 CONFIG("secondary_radius", radiusserver[1], IPv4),
110 CONFIG("primary_radius_port", radiusport[0], SHORT),
111 CONFIG("secondary_radius_port", radiusport[1], SHORT),
112 CONFIG("radius_accounting", radius_accounting, BOOL),
113 CONFIG("radius_interim", radius_interim, INT),
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 void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len);
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].opened)
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].opened)
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 <= config->cluster_highest_sessionid ; ++s)
819 {
820 if (!session[s].opened)
821 continue;
822
823 if (session[s].walled_garden)
824 continue; // Skip walled garden users.
825
826 if (!strncmp(session[s].user, username, 128))
827 return s;
828
829 }
830 return 0; // Not found.
831 }
832
833 void send_garp(in_addr_t ip)
834 {
835 int s;
836 struct ifreq ifr;
837 uint8_t mac[6];
838
839 s = socket(PF_INET, SOCK_DGRAM, 0);
840 if (s < 0)
841 {
842 LOG(0, 0, 0, "Error creating socket for GARP: %s\n", strerror(errno));
843 return;
844 }
845 memset(&ifr, 0, sizeof(ifr));
846 strncpy(ifr.ifr_name, "eth0", sizeof(ifr.ifr_name) - 1);
847 if (ioctl(s, SIOCGIFHWADDR, &ifr) < 0)
848 {
849 LOG(0, 0, 0, "Error getting eth0 hardware address for GARP: %s\n", strerror(errno));
850 close(s);
851 return;
852 }
853 memcpy(mac, &ifr.ifr_hwaddr.sa_data, 6*sizeof(char));
854 if (ioctl(s, SIOCGIFINDEX, &ifr) < 0)
855 {
856 LOG(0, 0, 0, "Error getting eth0 interface index for GARP: %s\n", strerror(errno));
857 close(s);
858 return;
859 }
860 close(s);
861 sendarp(ifr.ifr_ifindex, mac, ip);
862 }
863
864 static sessiont *sessiontbysessionidt(sessionidt s)
865 {
866 if (!s || s >= MAXSESSION) return NULL;
867 return &session[s];
868 }
869
870 static sessionidt sessionidtbysessiont(sessiont *s)
871 {
872 sessionidt val = s-session;
873 if (s < session || val >= MAXSESSION) return 0;
874 return val;
875 }
876
877 // actually send a control message for a specific tunnel
878 void tunnelsend(uint8_t * buf, uint16_t l, tunnelidt t)
879 {
880 struct sockaddr_in addr;
881
882 CSTAT(tunnelsend);
883
884 if (!t)
885 {
886 static int backtrace_count = 0;
887 LOG(0, 0, t, "tunnelsend called with 0 as tunnel id\n");
888 STAT(tunnel_tx_errors);
889 log_backtrace(backtrace_count, 5)
890 return;
891 }
892
893 if (!tunnel[t].ip)
894 {
895 static int backtrace_count = 0;
896 LOG(1, 0, t, "Error sending data out tunnel: no remote endpoint (tunnel not set up)\n");
897 log_backtrace(backtrace_count, 5)
898 STAT(tunnel_tx_errors);
899 return;
900 }
901
902 memset(&addr, 0, sizeof(addr));
903 addr.sin_family = AF_INET;
904 *(uint32_t *) & addr.sin_addr = htonl(tunnel[t].ip);
905 addr.sin_port = htons(tunnel[t].port);
906
907 // sequence expected, if sequence in message
908 if (*buf & 0x08) *(uint16_t *) (buf + ((*buf & 0x40) ? 10 : 8)) = htons(tunnel[t].nr);
909
910 // If this is a control message, deal with retries
911 if (*buf & 0x80)
912 {
913 tunnel[t].last = time_now; // control message sent
914 tunnel[t].retry = backoff(tunnel[t].try); // when to resend
915 if (tunnel[t].try > 1)
916 {
917 STAT(tunnel_retries);
918 LOG(3, 0, t, "Control message resend try %d\n", tunnel[t].try);
919 }
920 }
921
922 if (sendto(udpfd, buf, l, 0, (void *) &addr, sizeof(addr)) < 0)
923 {
924 LOG(0, ntohs((*(uint16_t *) (buf + 6))), t, "Error sending data out tunnel: %s (udpfd=%d, buf=%p, len=%d, dest=%s)\n",
925 strerror(errno), udpfd, buf, l, inet_ntoa(addr.sin_addr));
926 STAT(tunnel_tx_errors);
927 return;
928 }
929
930 LOG_HEX(5, "Send Tunnel Data", buf, l);
931 STAT(tunnel_tx_packets);
932 INC_STAT(tunnel_tx_bytes, l);
933 }
934
935 //
936 // Tiny helper function to write data to
937 // the 'tun' device.
938 //
939 int tun_write(uint8_t * data, int size)
940 {
941 return write(tunfd, data, size);
942 }
943
944 // process outgoing (to tunnel) IP
945 //
946 static void processipout(uint8_t * buf, int len)
947 {
948 sessionidt s;
949 sessiont *sp;
950 tunnelidt t;
951 in_addr_t ip;
952
953 char *data = buf; // Keep a copy of the originals.
954 int size = len;
955
956 uint8_t b[MAXETHER + 20];
957
958 CSTAT(processipout);
959
960 if (len < MIN_IP_SIZE)
961 {
962 LOG(1, 0, 0, "Short IP, %d bytes\n", len);
963 STAT(tun_rx_errors);
964 return;
965 }
966 if (len >= MAXETHER)
967 {
968 LOG(1, 0, 0, "Oversize IP packet %d bytes\n", len);
969 STAT(tun_rx_errors);
970 return;
971 }
972
973 // Skip the tun header
974 buf += 4;
975 len -= 4;
976
977 // Got an IP header now
978 if (*(uint8_t *)(buf) >> 4 != 4)
979 {
980 LOG(1, 0, 0, "IP: Don't understand anything except IPv4\n");
981 return;
982 }
983
984 ip = *(uint32_t *)(buf + 16);
985 if (!(s = sessionbyip(ip)))
986 {
987 // Is this a packet for a session that doesn't exist?
988 static int rate = 0; // Number of ICMP packets we've sent this second.
989 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
990
991 if (last != time_now)
992 {
993 last = time_now;
994 rate = 0;
995 }
996
997 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
998 {
999 LOG(4, 0, 0, "IP: Sending ICMP host unreachable to %s\n", fmtaddr(*(in_addr_t *)(buf + 12), 0));
1000 host_unreachable(*(in_addr_t *)(buf + 12), *(uint16_t *)(buf + 4), ip, buf, (len < 64) ? 64 : len);
1001 }
1002 return;
1003 }
1004 t = session[s].tunnel;
1005 sp = &session[s];
1006
1007 // DoS prevention: enforce a maximum number of packets per 0.1s for a session
1008 if (config->max_packets > 0)
1009 {
1010 if (sess_local[s].last_packet_out == TIME)
1011 {
1012 int max = config->max_packets;
1013
1014 // All packets for throttled sessions are handled by the
1015 // master, so further limit by using the throttle rate.
1016 // A bit of a kludge, since throttle rate is in kbps,
1017 // but should still be generous given our average DSL
1018 // packet size is 200 bytes: a limit of 28kbps equates
1019 // to around 180 packets per second.
1020 if (!config->cluster_iam_master && sp->throttle_out && sp->throttle_out < max)
1021 max = sp->throttle_out;
1022
1023 if (++sess_local[s].packets_out > max)
1024 {
1025 sess_local[s].packets_dropped++;
1026 return;
1027 }
1028 }
1029 else
1030 {
1031 if (sess_local[s].packets_dropped)
1032 {
1033 INC_STAT(tun_rx_dropped, sess_local[s].packets_dropped);
1034 LOG(3, s, t, "Dropped %u/%u packets to %s for %suser %s\n",
1035 sess_local[s].packets_dropped, sess_local[s].packets_out,
1036 fmtaddr(ip, 0), sp->throttle_out ? "throttled " : "",
1037 sp->user);
1038 }
1039
1040 sess_local[s].last_packet_out = TIME;
1041 sess_local[s].packets_out = 1;
1042 sess_local[s].packets_dropped = 0;
1043 }
1044 }
1045
1046 // run access-list if any
1047 if (session[s].filter_out && !ip_filter(buf, len, session[s].filter_out - 1))
1048 return;
1049
1050 if (sp->tbf_out)
1051 {
1052 // Are we throttling this session?
1053 if (config->cluster_iam_master)
1054 tbf_queue_packet(sp->tbf_out, data, size);
1055 else
1056 master_throttle_packet(sp->tbf_out, data, size);
1057 return;
1058 }
1059 else if (sp->walled_garden && !config->cluster_iam_master)
1060 {
1061 // We are walled-gardening this
1062 master_garden_packet(s, data, size);
1063 return;
1064 }
1065
1066 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1067
1068 // Add on L2TP header
1069 {
1070 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1071 if (!p) return;
1072 tunnelsend(b, len + (p-b), t); // send it...
1073 }
1074
1075 // Snooping this session, send it to intercept box
1076 if (sp->snoop_ip && sp->snoop_port)
1077 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1078
1079 sp->cout += len; // byte count
1080 sp->total_cout += len; // byte count
1081 sp->pout++;
1082 udp_tx += len;
1083 sess_local[s].cout += len; // To send to master..
1084 }
1085
1086 // process outgoing (to tunnel) IPv6
1087 //
1088 static void processipv6out(uint8_t * buf, int len)
1089 {
1090 sessionidt s;
1091 sessiont *sp;
1092 tunnelidt t;
1093 in_addr_t ip;
1094 struct in6_addr ip6;
1095
1096 char *data = buf; // Keep a copy of the originals.
1097 int size = len;
1098
1099 uint8_t b[MAXETHER + 20];
1100
1101 CSTAT(processipv6out);
1102
1103 if (len < MIN_IP_SIZE)
1104 {
1105 LOG(1, 0, 0, "Short IPv6, %d bytes\n", len);
1106 STAT(tunnel_tx_errors);
1107 return;
1108 }
1109 if (len >= MAXETHER)
1110 {
1111 LOG(1, 0, 0, "Oversize IPv6 packet %d bytes\n", len);
1112 STAT(tunnel_tx_errors);
1113 return;
1114 }
1115
1116 // Skip the tun header
1117 buf += 4;
1118 len -= 4;
1119
1120 // Got an IP header now
1121 if (*(uint8_t *)(buf) >> 4 != 6)
1122 {
1123 LOG(1, 0, 0, "IP: Don't understand anything except IPv6\n");
1124 return;
1125 }
1126
1127 ip6 = *(struct in6_addr *)(buf+24);
1128 s = sessionbyipv6(ip6);
1129
1130 if (s == 0)
1131 {
1132 ip = *(uint32_t *)(buf + 32);
1133 s = sessionbyip(ip);
1134 }
1135
1136 if (s == 0)
1137 {
1138 // Is this a packet for a session that doesn't exist?
1139 static int rate = 0; // Number of ICMP packets we've sent this second.
1140 static int last = 0; // Last time we reset the ICMP packet counter 'rate'.
1141
1142 if (last != time_now)
1143 {
1144 last = time_now;
1145 rate = 0;
1146 }
1147
1148 if (rate++ < config->icmp_rate) // Only send a max of icmp_rate per second.
1149 {
1150 // FIXME: Should send icmp6 host unreachable
1151 }
1152 return;
1153 }
1154 t = session[s].tunnel;
1155 sp = &session[s];
1156
1157 // FIXME: add DoS prevention/filters?
1158
1159 if (sp->tbf_out)
1160 {
1161 // Are we throttling this session?
1162 if (config->cluster_iam_master)
1163 tbf_queue_packet(sp->tbf_out, data, size);
1164 else
1165 master_throttle_packet(sp->tbf_out, data, size);
1166 return;
1167 }
1168 else if (sp->walled_garden && !config->cluster_iam_master)
1169 {
1170 // We are walled-gardening this
1171 master_garden_packet(s, data, size);
1172 return;
1173 }
1174
1175 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1176
1177 // Add on L2TP header
1178 {
1179 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIPV6);
1180 if (!p) return;
1181 tunnelsend(b, len + (p-b), t); // send it...
1182 }
1183
1184 // Snooping this session, send it to intercept box
1185 if (sp->snoop_ip && sp->snoop_port)
1186 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1187
1188 sp->cout += len; // byte count
1189 sp->total_cout += len; // byte count
1190 sp->pout++;
1191 udp_tx += len;
1192 sess_local[s].cout += len; // To send to master..
1193 }
1194
1195 //
1196 // Helper routine for the TBF filters.
1197 // Used to send queued data in to the user!
1198 //
1199 static void send_ipout(sessionidt s, uint8_t *buf, int len)
1200 {
1201 sessiont *sp;
1202 tunnelidt t;
1203 in_addr_t ip;
1204
1205 uint8_t b[MAXETHER + 20];
1206
1207 if (len < 0 || len > MAXETHER)
1208 {
1209 LOG(1, 0, 0, "Odd size IP packet: %d bytes\n", len);
1210 return;
1211 }
1212
1213 // Skip the tun header
1214 buf += 4;
1215 len -= 4;
1216
1217 ip = *(in_addr_t *)(buf + 16);
1218
1219 if (!session[s].ip)
1220 return;
1221
1222 t = session[s].tunnel;
1223 sp = &session[s];
1224
1225 LOG(5, s, t, "Ethernet -> Tunnel (%d bytes)\n", len);
1226
1227 // Add on L2TP header
1228 {
1229 uint8_t *p = makeppp(b, sizeof(b), buf, len, t, s, PPPIP);
1230 if (!p) return;
1231 tunnelsend(b, len + (p-b), t); // send it...
1232 }
1233
1234 // Snooping this session.
1235 if (sp->snoop_ip && sp->snoop_port)
1236 snoop_send_packet(buf, len, sp->snoop_ip, sp->snoop_port);
1237
1238 sp->cout += len; // byte count
1239 sp->total_cout += len; // byte count
1240 sp->pout++;
1241 udp_tx += len;
1242 sess_local[s].cout += len; // To send to master..
1243 }
1244
1245 // add an AVP (16 bit)
1246 static void control16(controlt * c, uint16_t avp, uint16_t val, uint8_t m)
1247 {
1248 uint16_t l = (m ? 0x8008 : 0x0008);
1249 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1250 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1251 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1252 *(uint16_t *) (c->buf + c->length + 6) = htons(val);
1253 c->length += 8;
1254 }
1255
1256 // add an AVP (32 bit)
1257 static void control32(controlt * c, uint16_t avp, uint32_t val, uint8_t m)
1258 {
1259 uint16_t l = (m ? 0x800A : 0x000A);
1260 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1261 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1262 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1263 *(uint32_t *) (c->buf + c->length + 6) = htonl(val);
1264 c->length += 10;
1265 }
1266
1267 // add an AVP (string)
1268 static void controls(controlt * c, uint16_t avp, char *val, uint8_t m)
1269 {
1270 uint16_t l = ((m ? 0x8000 : 0) + strlen(val) + 6);
1271 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1272 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1273 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1274 memcpy(c->buf + c->length + 6, val, strlen(val));
1275 c->length += 6 + strlen(val);
1276 }
1277
1278 // add a binary AVP
1279 static void controlb(controlt * c, uint16_t avp, char *val, unsigned int len, uint8_t m)
1280 {
1281 uint16_t l = ((m ? 0x8000 : 0) + len + 6);
1282 *(uint16_t *) (c->buf + c->length + 0) = htons(l);
1283 *(uint16_t *) (c->buf + c->length + 2) = htons(0);
1284 *(uint16_t *) (c->buf + c->length + 4) = htons(avp);
1285 memcpy(c->buf + c->length + 6, val, len);
1286 c->length += 6 + len;
1287 }
1288
1289 // new control connection
1290 static controlt *controlnew(uint16_t mtype)
1291 {
1292 controlt *c;
1293 if (!controlfree)
1294 c = malloc(sizeof(controlt));
1295 else
1296 {
1297 c = controlfree;
1298 controlfree = c->next;
1299 }
1300 assert(c);
1301 c->next = 0;
1302 *(uint16_t *) (c->buf + 0) = htons(0xC802); // flags/ver
1303 c->length = 12;
1304 control16(c, 0, mtype, 1);
1305 return c;
1306 }
1307
1308 // send zero block if nothing is waiting
1309 // (ZLB send).
1310 static void controlnull(tunnelidt t)
1311 {
1312 uint8_t buf[12];
1313 if (tunnel[t].controlc) // Messages queued; They will carry the ack.
1314 return;
1315
1316 *(uint16_t *) (buf + 0) = htons(0xC802); // flags/ver
1317 *(uint16_t *) (buf + 2) = htons(12); // length
1318 *(uint16_t *) (buf + 4) = htons(tunnel[t].far); // tunnel
1319 *(uint16_t *) (buf + 6) = htons(0); // session
1320 *(uint16_t *) (buf + 8) = htons(tunnel[t].ns); // sequence
1321 *(uint16_t *) (buf + 10) = htons(tunnel[t].nr); // sequence
1322 tunnelsend(buf, 12, t);
1323 }
1324
1325 // add a control message to a tunnel, and send if within window
1326 static void controladd(controlt * c, tunnelidt t, sessionidt far)
1327 {
1328 *(uint16_t *) (c->buf + 2) = htons(c->length); // length
1329 *(uint16_t *) (c->buf + 4) = htons(tunnel[t].far); // tunnel
1330 *(uint16_t *) (c->buf + 6) = htons(far); // session
1331 *(uint16_t *) (c->buf + 8) = htons(tunnel[t].ns); // sequence
1332 tunnel[t].ns++; // advance sequence
1333 // link in message in to queue
1334 if (tunnel[t].controlc)
1335 tunnel[t].controle->next = c;
1336 else
1337 tunnel[t].controls = c;
1338
1339 tunnel[t].controle = c;
1340 tunnel[t].controlc++;
1341
1342 // send now if space in window
1343 if (tunnel[t].controlc <= tunnel[t].window)
1344 {
1345 tunnel[t].try = 0; // first send
1346 tunnelsend(c->buf, c->length, t);
1347 }
1348 }
1349
1350 //
1351 // Throttle or Unthrottle a session
1352 //
1353 // Throttle the data from/to through a session to no more than
1354 // 'rate_in' kbit/sec in (from user) or 'rate_out' kbit/sec out (to
1355 // user).
1356 //
1357 // If either value is -1, the current value is retained for that
1358 // direction.
1359 //
1360 void throttle_session(sessionidt s, int rate_in, int rate_out)
1361 {
1362 if (!session[s].opened)
1363 return; // No-one home.
1364
1365 if (!*session[s].user)
1366 return; // User not logged in
1367
1368 if (rate_in >= 0)
1369 {
1370 int bytes = rate_in * 1024 / 8; // kbits to bytes
1371 if (session[s].tbf_in)
1372 free_tbf(session[s].tbf_in);
1373
1374 if (rate_in > 0)
1375 session[s].tbf_in = new_tbf(s, bytes * 2, bytes, send_ipin);
1376 else
1377 session[s].tbf_in = 0;
1378
1379 session[s].throttle_in = rate_in;
1380 }
1381
1382 if (rate_out >= 0)
1383 {
1384 int bytes = rate_out * 1024 / 8;
1385 if (session[s].tbf_out)
1386 free_tbf(session[s].tbf_out);
1387
1388 if (rate_out > 0)
1389 session[s].tbf_out = new_tbf(s, bytes * 2, bytes, send_ipout);
1390 else
1391 session[s].tbf_out = 0;
1392
1393 session[s].throttle_out = rate_out;
1394 }
1395 }
1396
1397 // add/remove filters from session (-1 = no change)
1398 static void filter_session(sessionidt s, int filter_in, int filter_out)
1399 {
1400 if (!session[s].opened)
1401 return; // No-one home.
1402
1403 if (!*session[s].user)
1404 return; // User not logged in
1405
1406 // paranoia
1407 if (filter_in > MAXFILTER) filter_in = -1;
1408 if (filter_out > MAXFILTER) filter_out = -1;
1409 if (session[s].filter_in > MAXFILTER) session[s].filter_in = 0;
1410 if (session[s].filter_out > MAXFILTER) session[s].filter_out = 0;
1411
1412 if (filter_in >= 0)
1413 {
1414 if (session[s].filter_in)
1415 ip_filters[session[s].filter_in - 1].used--;
1416
1417 if (filter_in > 0)
1418 ip_filters[filter_in - 1].used++;
1419
1420 session[s].filter_in = filter_in;
1421 }
1422
1423 if (filter_out >= 0)
1424 {
1425 if (session[s].filter_out)
1426 ip_filters[session[s].filter_out - 1].used--;
1427
1428 if (filter_out > 0)
1429 ip_filters[filter_out - 1].used++;
1430
1431 session[s].filter_out = filter_out;
1432 }
1433 }
1434
1435 // start tidy shutdown of session
1436 void sessionshutdown(sessionidt s, char *reason, int result, int error)
1437 {
1438 int walled_garden = session[s].walled_garden;
1439
1440
1441 CSTAT(sessionshutdown);
1442
1443 if (!session[s].opened)
1444 {
1445 LOG(3, s, session[s].tunnel, "Called sessionshutdown on an unopened session.\n");
1446 return; // not a live session
1447 }
1448
1449 if (!session[s].die)
1450 {
1451 struct param_kill_session data = { &tunnel[session[s].tunnel], &session[s] };
1452 LOG(2, s, session[s].tunnel, "Shutting down session %d: %s\n", s, reason);
1453 run_plugins(PLUGIN_KILL_SESSION, &data);
1454 }
1455
1456 if (session[s].ip && !walled_garden && !session[s].die)
1457 {
1458 // RADIUS Stop message
1459 uint16_t r = sess_local[s].radius;
1460 if (!r)
1461 r = radiusnew(s);
1462
1463 if (r)
1464 {
1465 // stop, if not already trying
1466 if (radius[r].state != RADIUSSTOP)
1467 radiussend(r, RADIUSSTOP);
1468 }
1469 else
1470 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Stop message\n");
1471
1472 // Save counters to dump to accounting file
1473 if (*config->accounting_dir && shut_acct_n < sizeof(shut_acct) / sizeof(*shut_acct))
1474 memcpy(&shut_acct[shut_acct_n++], &session[s], sizeof(session[s]));
1475 }
1476
1477 if (session[s].ip)
1478 { // IP allocated, clear and unroute
1479 int r;
1480 int routed = 0;
1481 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
1482 {
1483 if ((session[s].ip & session[s].route[r].mask) ==
1484 (session[s].route[r].ip & session[s].route[r].mask))
1485 routed++;
1486
1487 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 0);
1488 session[s].route[r].ip = 0;
1489 }
1490
1491 if (session[s].ip_pool_index == -1) // static ip
1492 {
1493 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
1494 session[s].ip = 0;
1495 }
1496 else
1497 free_ip_address(s);
1498
1499 // unroute IPv6, if setup
1500 if (session[s].flags & SF_IPV6_ROUTED)
1501 route6set(s, session[s].ipv6route, session[s].ipv6prefixlen, 0);
1502 }
1503
1504 if (session[s].throttle_in || session[s].throttle_out) // Unthrottle if throttled.
1505 throttle_session(s, 0, 0);
1506
1507 if (result)
1508 { // Send CDN
1509 controlt *c = controlnew(14); // sending CDN
1510 if (error)
1511 {
1512 char buf[4];
1513 *(uint16_t *) buf = htons(result);
1514 *(uint16_t *) (buf+2) = htons(error);
1515 controlb(c, 1, buf, 4, 1);
1516 }
1517 else
1518 control16(c, 1, result, 1);
1519
1520 control16(c, 14, s, 1); // assigned session (our end)
1521 controladd(c, session[s].tunnel, session[s].far); // send the message
1522 }
1523
1524 if (!session[s].die)
1525 session[s].die = TIME + 150; // Clean up in 15 seconds
1526
1527 // update filter refcounts
1528 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
1529 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
1530
1531 cluster_send_session(s);
1532 }
1533
1534 void sendipcp(tunnelidt t, sessionidt s)
1535 {
1536 uint8_t buf[MAXCONTROL];
1537 uint16_t r = sess_local[s].radius;
1538 uint8_t *q;
1539
1540 CSTAT(sendipcp);
1541
1542 if (!r)
1543 r = radiusnew(s);
1544
1545 if (!r)
1546 {
1547 sessionshutdown(s, "No free RADIUS sessions for IPCP", 3, 0);
1548 return;
1549 }
1550
1551 if (radius[r].state != RADIUSIPCP)
1552 {
1553 radius[r].state = RADIUSIPCP;
1554 radius[r].try = 0;
1555 }
1556
1557 radius[r].retry = backoff(radius[r].try++);
1558 if (radius[r].try > 10)
1559 {
1560 radiusclear(r, s); // Clear radius session.
1561 sessionshutdown(s, "No reply to IPCP.", 3, 0);
1562 return;
1563 }
1564
1565 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPCP);
1566 if (!q) return;
1567
1568 *q = ConfigReq;
1569 q[1] = r >> RADIUS_SHIFT; // ID, dont care, we only send one type of request
1570 *(uint16_t *) (q + 2) = htons(10);
1571 q[4] = 3;
1572 q[5] = 6;
1573 *(in_addr_t *) (q + 6) = config->peer_address ? config->peer_address :
1574 config->bind_address ? config->bind_address :
1575 my_address; // send my IP
1576
1577 tunnelsend(buf, 10 + (q - buf), t); // send it
1578 session[s].flags &= ~SF_IPCP_ACKED; // Clear flag.
1579
1580 // If we have an IPv6 prefix length configured, assume we should
1581 // try to negotiate an IPv6 session as well. Unless we've had a
1582 // (N)ACK for IPV6CP.
1583 if (config->ipv6_prefix.s6_addr[0] > 0 &&
1584 !(session[s].flags & SF_IPV6CP_ACKED) &&
1585 !(session[s].flags & SF_IPV6_NACKED))
1586 {
1587 q = makeppp(buf,sizeof(buf), 0, 0, t, s, PPPIPV6CP);
1588 if (!q) return;
1589
1590 *q = ConfigReq;
1591 q[1] = r >> RADIUS_SHIFT; // ID, don't care, we
1592 // only send one type
1593 // of request
1594 *(uint16_t *) (q + 2) = htons(14);
1595 q[4] = 1;
1596 q[5] = 10;
1597 *(uint32_t *) (q + 6) = 0; // We'll be prefix::1
1598 *(uint32_t *) (q + 10) = 0;
1599 q[13] = 1;
1600
1601 tunnelsend(buf, 14 + (q - buf), t); // send it
1602 }
1603 }
1604
1605 static void sessionclear(sessionidt s)
1606 {
1607 memset(&session[s], 0, sizeof(session[s]));
1608 memset(&sess_local[s], 0, sizeof(sess_local[s]));
1609 memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
1610
1611 session[s].tunnel = T_FREE; // Mark it as free.
1612 session[s].next = sessionfree;
1613 sessionfree = s;
1614 }
1615
1616 // kill a session now
1617 void sessionkill(sessionidt s, char *reason)
1618 {
1619
1620 CSTAT(sessionkill);
1621
1622 if (!session[s].opened) // not alive
1623 return;
1624
1625 if (session[s].next)
1626 {
1627 LOG(0, s, session[s].tunnel, "Tried to kill a session with next pointer set (%d)\n", session[s].next);
1628 return;
1629 }
1630
1631 session[s].die = TIME;
1632 sessionshutdown(s, reason, 3, 0); // close radius/routes, etc.
1633 if (sess_local[s].radius)
1634 radiusclear(sess_local[s].radius, s); // cant send clean accounting data, session is killed
1635
1636 LOG(2, s, session[s].tunnel, "Kill session %d (%s): %s\n", s, session[s].user, reason);
1637 sessionclear(s);
1638 cluster_send_session(s);
1639 }
1640
1641 static void tunnelclear(tunnelidt t)
1642 {
1643 if (!t) return;
1644 memset(&tunnel[t], 0, sizeof(tunnel[t]));
1645 tunnel[t].state = TUNNELFREE;
1646 }
1647
1648 // kill a tunnel now
1649 static void tunnelkill(tunnelidt t, char *reason)
1650 {
1651 sessionidt s;
1652 controlt *c;
1653
1654 CSTAT(tunnelkill);
1655
1656 tunnel[t].state = TUNNELDIE;
1657
1658 // free control messages
1659 while ((c = tunnel[t].controls))
1660 {
1661 controlt * n = c->next;
1662 tunnel[t].controls = n;
1663 tunnel[t].controlc--;
1664 c->next = controlfree;
1665 controlfree = c;
1666 }
1667 // kill sessions
1668 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1669 if (session[s].tunnel == t)
1670 sessionkill(s, reason);
1671
1672 // free tunnel
1673 tunnelclear(t);
1674 LOG(1, 0, t, "Kill tunnel %d: %s\n", t, reason);
1675 cli_tunnel_actions[t].action = 0;
1676 cluster_send_tunnel(t);
1677 }
1678
1679 // shut down a tunnel cleanly
1680 static void tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg)
1681 {
1682 sessionidt s;
1683
1684 CSTAT(tunnelshutdown);
1685
1686 if (!tunnel[t].last || !tunnel[t].far || tunnel[t].state == TUNNELFREE)
1687 {
1688 // never set up, can immediately kill
1689 tunnelkill(t, reason);
1690 return;
1691 }
1692 LOG(1, 0, t, "Shutting down tunnel %d (%s)\n", t, reason);
1693
1694 // close session
1695 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
1696 if (session[s].tunnel == t)
1697 sessionshutdown(s, reason, 3, 0);
1698
1699 tunnel[t].state = TUNNELDIE;
1700 tunnel[t].die = TIME + 700; // Clean up in 70 seconds
1701 cluster_send_tunnel(t);
1702 // TBA - should we wait for sessions to stop?
1703 if (result)
1704 {
1705 controlt *c = controlnew(4); // sending StopCCN
1706 if (error)
1707 {
1708 char buf[64];
1709 int l = 4;
1710 *(uint16_t *) buf = htons(result);
1711 *(uint16_t *) (buf+2) = htons(error);
1712 if (msg)
1713 {
1714 int m = strlen(msg);
1715 if (m + 4 > sizeof(buf))
1716 m = sizeof(buf) - 4;
1717
1718 memcpy(buf+4, msg, m);
1719 l += m;
1720 }
1721
1722 controlb(c, 1, buf, l, 1);
1723 }
1724 else
1725 control16(c, 1, result, 1);
1726
1727 control16(c, 9, t, 1); // assigned tunnel (our end)
1728 controladd(c, t, 0); // send the message
1729 }
1730 }
1731
1732 // read and process packet on tunnel (UDP)
1733 void processudp(uint8_t * buf, int len, struct sockaddr_in *addr)
1734 {
1735 char *chapresponse = NULL;
1736 uint16_t l = len, t = 0, s = 0, ns = 0, nr = 0;
1737 uint8_t *p = buf + 2;
1738
1739
1740 CSTAT(processudp);
1741
1742 udp_rx += len;
1743 udp_rx_pkt++;
1744 LOG_HEX(5, "UDP Data", buf, len);
1745 STAT(tunnel_rx_packets);
1746 INC_STAT(tunnel_rx_bytes, len);
1747 if (len < 6)
1748 {
1749 LOG(1, 0, 0, "Short UDP, %d bytes\n", len);
1750 STAT(tunnel_rx_errors);
1751 return;
1752 }
1753 if ((buf[1] & 0x0F) != 2)
1754 {
1755 LOG(1, 0, 0, "Bad L2TP ver %d\n", (buf[1] & 0x0F) != 2);
1756 STAT(tunnel_rx_errors);
1757 return;
1758 }
1759 if (*buf & 0x40)
1760 { // length
1761 l = ntohs(*(uint16_t *) p);
1762 p += 2;
1763 }
1764 t = ntohs(*(uint16_t *) p);
1765 p += 2;
1766 s = ntohs(*(uint16_t *) p);
1767 p += 2;
1768 if (s >= MAXSESSION)
1769 {
1770 LOG(1, s, t, "Received UDP packet with invalid session ID\n");
1771 STAT(tunnel_rx_errors);
1772 return;
1773 }
1774 if (t >= MAXTUNNEL)
1775 {
1776 LOG(1, s, t, "Received UDP packet with invalid tunnel ID\n");
1777 STAT(tunnel_rx_errors);
1778 return;
1779 }
1780 if (*buf & 0x08)
1781 { // ns/nr
1782 ns = ntohs(*(uint16_t *) p);
1783 p += 2;
1784 nr = ntohs(*(uint16_t *) p);
1785 p += 2;
1786 }
1787 if (*buf & 0x02)
1788 { // offset
1789 uint16_t o = ntohs(*(uint16_t *) p);
1790 p += o + 2;
1791 }
1792 if ((p - buf) > l)
1793 {
1794 LOG(1, s, t, "Bad length %d>%d\n", (int) (p - buf), l);
1795 STAT(tunnel_rx_errors);
1796 return;
1797 }
1798 l -= (p - buf);
1799 if (*buf & 0x80)
1800 { // control
1801 uint16_t message = 0xFFFF; // message type
1802 uint8_t fatal = 0;
1803 uint8_t mandatory = 0;
1804 uint8_t authtype = 0; // proxy auth type
1805 uint16_t asession = 0; // assigned session
1806 uint32_t amagic = 0; // magic number
1807 uint8_t aflags = 0; // flags from last LCF
1808 uint16_t version = 0x0100; // protocol version (we handle 0.0 as well and send that back just in case)
1809 char called[MAXTEL] = ""; // called number
1810 char calling[MAXTEL] = ""; // calling number
1811
1812 if (!config->cluster_iam_master)
1813 {
1814 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
1815 return;
1816 }
1817
1818 // control messages must have bits 0x80|0x40|0x08
1819 // (type, length and sequence) set, and bits 0x02|0x01
1820 // (offset and priority) clear
1821 if ((*buf & 0xCB) != 0xC8)
1822 {
1823 LOG(1, s, t, "Bad control header %02X\n", *buf);
1824 STAT(tunnel_rx_errors);
1825 return;
1826 }
1827
1828 // check for duplicate tunnel open message
1829 if (!t && ns == 0)
1830 {
1831 int i;
1832
1833 //
1834 // Is this a duplicate of the first packet? (SCCRQ)
1835 //
1836 for (i = 1; i <= config->cluster_highest_tunnelid ; ++i)
1837 {
1838 if (tunnel[i].state != TUNNELOPENING ||
1839 tunnel[i].ip != ntohl(*(in_addr_t *) & addr->sin_addr) ||
1840 tunnel[i].port != ntohs(addr->sin_port) )
1841 continue;
1842 t = i;
1843 LOG(3, s, t, "Duplicate SCCRQ?\n");
1844 break;
1845 }
1846 }
1847
1848 LOG(3, s, t, "Control message (%d bytes): (unacked %d) l-ns %d l-nr %d r-ns %d r-nr %d\n",
1849 l, tunnel[t].controlc, tunnel[t].ns, tunnel[t].nr, ns, nr);
1850
1851 // if no tunnel specified, assign one
1852 if (!t)
1853 {
1854 if (!(t = new_tunnel()))
1855 {
1856 LOG(1, 0, 0, "No more tunnels\n");
1857 STAT(tunnel_overflow);
1858 return;
1859 }
1860 tunnelclear(t);
1861 tunnel[t].ip = ntohl(*(in_addr_t *) & addr->sin_addr);
1862 tunnel[t].port = ntohs(addr->sin_port);
1863 tunnel[t].window = 4; // default window
1864 STAT(tunnel_created);
1865 LOG(1, 0, t, " New tunnel from %s:%u ID %d\n",
1866 fmtaddr(htonl(tunnel[t].ip), 0), tunnel[t].port, t);
1867 }
1868
1869 // If the 'ns' just received is not the 'nr' we're
1870 // expecting, just send an ack and drop it.
1871 //
1872 // if 'ns' is less, then we got a retransmitted packet.
1873 // if 'ns' is greater than missed a packet. Either way
1874 // we should ignore it.
1875 if (ns != tunnel[t].nr)
1876 {
1877 // is this the sequence we were expecting?
1878 STAT(tunnel_rx_errors);
1879 LOG(1, 0, t, " Out of sequence tunnel %d, (%d is not the expected %d)\n",
1880 t, ns, tunnel[t].nr);
1881
1882 if (l) // Is this not a ZLB?
1883 controlnull(t);
1884 return;
1885 }
1886
1887 // This is used to time out old tunnels
1888 tunnel[t].lastrec = time_now;
1889
1890 // check sequence of this message
1891 {
1892 int skip = tunnel[t].window; // track how many in-window packets are still in queue
1893 // some to clear maybe?
1894 while (tunnel[t].controlc > 0 && (((tunnel[t].ns - tunnel[t].controlc) - nr) & 0x8000))
1895 {
1896 controlt *c = tunnel[t].controls;
1897 tunnel[t].controls = c->next;
1898 tunnel[t].controlc--;
1899 c->next = controlfree;
1900 controlfree = c;
1901 skip--;
1902 tunnel[t].try = 0; // we have progress
1903 }
1904
1905 // receiver advance (do here so quoted correctly in any sends below)
1906 if (l) tunnel[t].nr = (ns + 1);
1907 if (skip < 0) skip = 0;
1908 if (skip < tunnel[t].controlc)
1909 {
1910 // some control packets can now be sent that were previous stuck out of window
1911 int tosend = tunnel[t].window - skip;
1912 controlt *c = tunnel[t].controls;
1913 while (c && skip)
1914 {
1915 c = c->next;
1916 skip--;
1917 }
1918 while (c && tosend)
1919 {
1920 tunnel[t].try = 0; // first send
1921 tunnelsend(c->buf, c->length, t);
1922 c = c->next;
1923 tosend--;
1924 }
1925 }
1926 if (!tunnel[t].controlc)
1927 tunnel[t].retry = 0; // caught up
1928 }
1929 if (l)
1930 { // if not a null message
1931 int result = 0;
1932 int error = 0;
1933 char *msg = 0;
1934
1935 // process AVPs
1936 while (l && !(fatal & 0x80)) // 0x80 = mandatory AVP
1937 {
1938 uint16_t n = (ntohs(*(uint16_t *) p) & 0x3FF);
1939 uint8_t *b = p;
1940 uint8_t flags = *p;
1941 uint16_t mtype;
1942 if (n > l)
1943 {
1944 LOG(1, s, t, "Invalid length in AVP\n");
1945 STAT(tunnel_rx_errors);
1946 return;
1947 }
1948 p += n; // next
1949 l -= n;
1950 if (flags & 0x3C) // reserved bits, should be clear
1951 {
1952 LOG(1, s, t, "Unrecognised AVP flags %02X\n", *b);
1953 fatal = flags;
1954 result = 2; // general error
1955 error = 3; // reserved field non-zero
1956 msg = 0;
1957 continue; // next
1958 }
1959 b += 2;
1960 if (*(uint16_t *) (b))
1961 {
1962 LOG(2, s, t, "Unknown AVP vendor %d\n", ntohs(*(uint16_t *) (b)));
1963 fatal = flags;
1964 result = 2; // general error
1965 error = 6; // generic vendor-specific error
1966 msg = "unsupported vendor-specific";
1967 continue; // next
1968 }
1969 b += 2;
1970 mtype = ntohs(*(uint16_t *) (b));
1971 b += 2;
1972 n -= 6;
1973
1974 if (flags & 0x40)
1975 {
1976 uint16_t orig_len;
1977
1978 // handle hidden AVPs
1979 if (!*config->l2tpsecret)
1980 {
1981 LOG(1, s, t, "Hidden AVP requested, but no L2TP secret.\n");
1982 fatal = flags;
1983 result = 2; // general error
1984 error = 6; // generic vendor-specific error
1985 msg = "secret not specified";
1986 continue;
1987 }
1988 if (!session[s].random_vector_length)
1989 {
1990 LOG(1, s, t, "Hidden AVP requested, but no random vector.\n");
1991 fatal = flags;
1992 result = 2; // general error
1993 error = 6; // generic
1994 msg = "no random vector";
1995 continue;
1996 }
1997 if (n < 8)
1998 {
1999 LOG(2, s, t, "Short hidden AVP.\n");
2000 fatal = flags;
2001 result = 2; // general error
2002 error = 2; // length is wrong
2003 msg = 0;
2004 continue;
2005 }
2006
2007 LOG(4, s, t, "Hidden AVP\n");
2008
2009 // Unhide the AVP
2010 unhide_value(b, n, mtype, session[s].random_vector, session[s].random_vector_length);
2011
2012 orig_len = ntohs(*(uint16_t *) b);
2013 if (orig_len > n + 2)
2014 {
2015 LOG(1, s, t, "Original length %d too long in hidden AVP of length %d; wrong secret?\n",
2016 orig_len, n);
2017
2018 fatal = flags;
2019 result = 2; // general error
2020 error = 2; // length is wrong
2021 msg = 0;
2022 continue;
2023 }
2024
2025 b += 2;
2026 n = orig_len;
2027 }
2028
2029 LOG(4, s, t, " AVP %d (%s) len %d\n", mtype, avp_name(mtype), n);
2030 switch (mtype)
2031 {
2032 case 0: // message type
2033 message = ntohs(*(uint16_t *) b);
2034 mandatory = flags & 0x80;
2035 LOG(4, s, t, " Message type = %d (%s)\n", *b, l2tp_message_type(message));
2036 break;
2037 case 1: // result code
2038 {
2039 uint16_t rescode = ntohs(*(uint16_t *) b);
2040 const char* resdesc = "(unknown)";
2041 if (message == 4)
2042 { /* StopCCN */
2043 resdesc = stopccn_result_code(rescode);
2044 }
2045 else if (message == 14)
2046 { /* CDN */
2047 resdesc = cdn_result_code(rescode);
2048 }
2049
2050 LOG(4, s, t, " Result Code %d: %s\n", rescode, resdesc);
2051 if (n >= 4)
2052 {
2053 uint16_t errcode = ntohs(*(uint16_t *)(b + 2));
2054 LOG(4, s, t, " Error Code %d: %s\n", errcode, error_code(errcode));
2055 }
2056 if (n > 4)
2057 LOG(4, s, t, " Error String: %.*s\n", n-4, b+4);
2058
2059 break;
2060 }
2061 break;
2062 case 2: // protocol version
2063 {
2064 version = ntohs(*(uint16_t *) (b));
2065 LOG(4, s, t, " Protocol version = %d\n", version);
2066 if (version && version != 0x0100)
2067 { // allow 0.0 and 1.0
2068 LOG(1, s, t, " Bad protocol version %04X\n", version);
2069 fatal = flags;
2070 result = 5; // unspported protocol version
2071 error = 0x0100; // supported version
2072 msg = 0;
2073 continue; // next
2074 }
2075 }
2076 break;
2077 case 3: // framing capabilities
2078 // LOG(4, s, t, "Framing capabilities\n");
2079 break;
2080 case 4: // bearer capabilities
2081 // LOG(4, s, t, "Bearer capabilities\n");
2082 break;
2083 case 5: // tie breaker
2084 // We never open tunnels, so we don't care about tie breakers
2085 // LOG(4, s, t, "Tie breaker\n");
2086 continue;
2087 case 6: // firmware revision
2088 // LOG(4, s, t, "Firmware revision\n");
2089 break;
2090 case 7: // host name
2091 memset(tunnel[t].hostname, 0, sizeof(tunnel[t].hostname));
2092 memcpy(tunnel[t].hostname, b, (n < sizeof(tunnel[t].hostname)) ? n : sizeof(tunnel[t].hostname) - 1);
2093 LOG(4, s, t, " Tunnel hostname = \"%s\"\n", tunnel[t].hostname);
2094 // TBA - to send to RADIUS
2095 break;
2096 case 8: // vendor name
2097 memset(tunnel[t].vendor, 0, sizeof(tunnel[t].vendor));
2098 memcpy(tunnel[t].vendor, b, (n < sizeof(tunnel[t].vendor)) ? n : sizeof(tunnel[t].vendor) - 1);
2099 LOG(4, s, t, " Vendor name = \"%s\"\n", tunnel[t].vendor);
2100 break;
2101 case 9: // assigned tunnel
2102 tunnel[t].far = ntohs(*(uint16_t *) (b));
2103 LOG(4, s, t, " Remote tunnel id = %d\n", tunnel[t].far);
2104 break;
2105 case 10: // rx window
2106 tunnel[t].window = ntohs(*(uint16_t *) (b));
2107 if (!tunnel[t].window)
2108 tunnel[t].window = 1; // window of 0 is silly
2109 LOG(4, s, t, " rx window = %d\n", tunnel[t].window);
2110 break;
2111 case 11: // Challenge
2112 {
2113 LOG(4, s, t, " LAC requested CHAP authentication for tunnel\n");
2114 build_chap_response(b, 2, n, &chapresponse);
2115 }
2116 break;
2117 case 13: // Response
2118 // Why did they send a response? We never challenge.
2119 LOG(2, s, t, " received unexpected challenge response\n");
2120 break;
2121
2122 case 14: // assigned session
2123 asession = session[s].far = ntohs(*(uint16_t *) (b));
2124 LOG(4, s, t, " assigned session = %d\n", asession);
2125 break;
2126 case 15: // call serial number
2127 LOG(4, s, t, " call serial number = %d\n", ntohl(*(uint32_t *)b));
2128 break;
2129 case 18: // bearer type
2130 LOG(4, s, t, " bearer type = %d\n", ntohl(*(uint32_t *)b));
2131 // TBA - for RADIUS
2132 break;
2133 case 19: // framing type
2134 LOG(4, s, t, " framing type = %d\n", ntohl(*(uint32_t *)b));
2135 // TBA
2136 break;
2137 case 21: // called number
2138 memset(called, 0, sizeof(called));
2139 memcpy(called, b, (n < sizeof(called)) ? n : sizeof(called) - 1);
2140 LOG(4, s, t, " Called <%s>\n", called);
2141 break;
2142 case 22: // calling number
2143 memset(calling, 0, sizeof(calling));
2144 memcpy(calling, b, (n < sizeof(calling)) ? n : sizeof(calling) - 1);
2145 LOG(4, s, t, " Calling <%s>\n", calling);
2146 break;
2147 case 23: // subtype
2148 break;
2149 case 24: // tx connect speed
2150 if (n == 4)
2151 {
2152 session[s].tx_connect_speed = ntohl(*(uint32_t *)b);
2153 }
2154 else
2155 {
2156 // AS5300s send connect speed as a string
2157 char tmp[30];
2158 memset(tmp, 0, sizeof(tmp));
2159 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2160 session[s].tx_connect_speed = atol(tmp);
2161 }
2162 LOG(4, s, t, " TX connect speed <%u>\n", session[s].tx_connect_speed);
2163 break;
2164 case 38: // rx connect speed
2165 if (n == 4)
2166 {
2167 session[s].rx_connect_speed = ntohl(*(uint32_t *)b);
2168 }
2169 else
2170 {
2171 // AS5300s send connect speed as a string
2172 char tmp[30];
2173 memset(tmp, 0, sizeof(tmp));
2174 memcpy(tmp, b, (n < sizeof(tmp)) ? n : sizeof(tmp) - 1);
2175 session[s].rx_connect_speed = atol(tmp);
2176 }
2177 LOG(4, s, t, " RX connect speed <%u>\n", session[s].rx_connect_speed);
2178 break;
2179 case 25: // Physical Channel ID
2180 {
2181 uint32_t tmp = ntohl(*(uint32_t *) b);
2182 LOG(4, s, t, " Physical Channel ID <%X>\n", tmp);
2183 break;
2184 }
2185 case 29: // Proxy Authentication Type
2186 {
2187 uint16_t atype = ntohs(*(uint16_t *)b);
2188 LOG(4, s, t, " Proxy Auth Type %d (%s)\n", atype, auth_type(atype));
2189 if (atype == 2)
2190 authtype = AUTHCHAP;
2191 else if (atype == 3)
2192 authtype = AUTHPAP;
2193
2194 break;
2195 }
2196 case 30: // Proxy Authentication Name
2197 {
2198 char authname[64];
2199 memset(authname, 0, sizeof(authname));
2200 memcpy(authname, b, (n < sizeof(authname)) ? n : sizeof(authname) - 1);
2201 LOG(4, s, t, " Proxy Auth Name (%s)\n",
2202 authname);
2203 break;
2204 }
2205 case 31: // Proxy Authentication Challenge
2206 {
2207 LOG(4, s, t, " Proxy Auth Challenge\n");
2208 if (sess_local[s].radius)
2209 memcpy(radius[sess_local[s].radius].auth, b, 16);
2210 break;
2211 }
2212 case 32: // Proxy Authentication ID
2213 {
2214 uint16_t authid = ntohs(*(uint16_t *)(b));
2215 LOG(4, s, t, " Proxy Auth ID (%d)\n", authid);
2216 if (sess_local[s].radius)
2217 radius[sess_local[s].radius].id = authid;
2218 break;
2219 }
2220 case 33: // Proxy Authentication Response
2221 LOG(4, s, t, " Proxy Auth Response\n");
2222 break;
2223 case 27: // last sent lcp
2224 { // find magic number
2225 uint8_t *p = b, *e = p + n;
2226 while (p + 1 < e && p[1] && p + p[1] <= e)
2227 {
2228 if (*p == 5 && p[1] == 6) // Magic-Number
2229 amagic = ntohl(*(uint32_t *) (p + 2));
2230 else if (*p == 3 && p[1] == 4 && *(uint16_t *) (p + 2) == htons(PPPPAP)) // Authentication-Protocol (PAP)
2231 authtype = AUTHPAP;
2232 else if (*p == 3 && p[1] == 5 && *(uint16_t *) (p + 2) == htons(PPPCHAP) && p[4] == 5) // Authentication-Protocol (CHAP)
2233 authtype = AUTHCHAP;
2234 else if (*p == 7) // Protocol-Field-Compression
2235 aflags |= SESSIONPFC;
2236 else if (*p == 8) // Address-and-Control-Field-Compression
2237 aflags |= SESSIONACFC;
2238 p += p[1];
2239 }
2240 }
2241 break;
2242 case 28: // last recv lcp confreq
2243 break;
2244 case 26: // Initial Received LCP CONFREQ
2245 break;
2246 case 39: // seq required - we control it as an LNS anyway...
2247 break;
2248 case 36: // Random Vector
2249 LOG(4, s, t, " Random Vector received. Enabled AVP Hiding.\n");
2250 memset(session[s].random_vector, 0, sizeof(session[s].random_vector));
2251 memcpy(session[s].random_vector, b, n);
2252 session[s].random_vector_length = n;
2253 break;
2254 default:
2255 {
2256 static char e[] = "unknown AVP 0xXXXX";
2257 LOG(2, s, t, " Unknown AVP type %d\n", mtype);
2258 fatal = flags;
2259 result = 2; // general error
2260 error = 8; // unknown mandatory AVP
2261 sprintf((msg = e) + 14, "%04x", mtype);
2262 continue; // next
2263 }
2264 }
2265 }
2266 // process message
2267 if (fatal & 0x80)
2268 tunnelshutdown(t, "Invalid mandatory AVP", result, error, msg);
2269 else
2270 switch (message)
2271 {
2272 case 1: // SCCRQ - Start Control Connection Request
2273 {
2274 controlt *c = controlnew(2); // sending SCCRP
2275 control16(c, 2, version, 1); // protocol version
2276 control32(c, 3, 3, 1); // framing
2277 controls(c, 7, tunnel[t].hostname, 1); // host name (TBA)
2278 if (chapresponse) controlb(c, 13, chapresponse, 16, 1); // Challenge response
2279 control16(c, 9, t, 1); // assigned tunnel
2280 controladd(c, t, 0); // send the resply
2281 }
2282 tunnel[t].state = TUNNELOPENING;
2283 break;
2284 case 2: // SCCRP
2285 tunnel[t].state = TUNNELOPEN;
2286 break;
2287 case 3: // SCCN
2288 tunnel[t].state = TUNNELOPEN;
2289 controlnull(t); // ack
2290 break;
2291 case 4: // StopCCN
2292 controlnull(t); // ack
2293 tunnelshutdown(t, "Stopped", 0, 0, 0); // Shut down cleanly
2294 break;
2295 case 6: // HELLO
2296 controlnull(t); // simply ACK
2297 break;
2298 case 7: // OCRQ
2299 // TBA
2300 break;
2301 case 8: // OCRO
2302 // TBA
2303 break;
2304 case 9: // OCCN
2305 // TBA
2306 break;
2307 case 10: // ICRQ
2308 if (sessionfree)
2309 {
2310 uint16_t r;
2311
2312 s = sessionfree;
2313 sessionfree = session[s].next;
2314 memset(&session[s], 0, sizeof(session[s]));
2315
2316 if (s > config->cluster_highest_sessionid)
2317 config->cluster_highest_sessionid = s;
2318
2319 // make a RADIUS session
2320 if ((r = radiusnew(s)))
2321 {
2322 controlt *c = controlnew(11); // sending ICRP
2323 session[s].opened = time_now;
2324 session[s].tunnel = t;
2325 session[s].far = asession;
2326 session[s].last_packet = time_now;
2327 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2328 control16(c, 14, s, 1); // assigned session
2329 controladd(c, t, asession); // send the reply
2330
2331 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
2332 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2333 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2334 STAT(session_created);
2335 break;
2336 }
2337
2338
2339 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
2340 sessionclear(s);
2341 }
2342 else
2343 {
2344 STAT(session_overflow);
2345 LOG(1, 0, t, "No free sessions\n");
2346 }
2347
2348 {
2349 controlt *c = controlnew(14); // CDN
2350 control16(c, 1, 4, 1); // temporary lack of resources
2351 controladd(c, session[s].tunnel, asession); // send the message
2352 }
2353 return;
2354 case 11: // ICRP
2355 // TBA
2356 break;
2357 case 12: // ICCN
2358 if (amagic == 0) amagic = time_now;
2359 session[s].magic = amagic; // set magic number
2360 session[s].l2tp_flags = aflags; // set flags received
2361 LOG(3, s, t, "Magic %X Flags %X\n", amagic, aflags);
2362 controlnull(t); // ack
2363 // proxy authentication type is not supported
2364 if (!(config->radius_authtypes & authtype))
2365 authtype = config->radius_authprefer;
2366
2367 // start LCP
2368 sendlcp(t, s, authtype);
2369 break;
2370 case 14: // CDN
2371 controlnull(t); // ack
2372 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2373 break;
2374 case 0xFFFF:
2375 LOG(1, s, t, "Missing message type\n");
2376 break;
2377 default:
2378 STAT(tunnel_rx_errors);
2379 if (mandatory)
2380 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2381 else
2382 LOG(1, s, t, "Unknown message type %d\n", message);
2383 break;
2384 }
2385 if (chapresponse) free(chapresponse);
2386 cluster_send_tunnel(t);
2387 }
2388 else
2389 {
2390 LOG(4, s, t, " Got a ZLB ack\n");
2391 }
2392 }
2393 else
2394 { // data
2395 uint16_t prot;
2396
2397 LOG_HEX(5, "Receive Tunnel Data", p, l);
2398 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2399 { // HDLC address header, discard
2400 p += 2;
2401 l -= 2;
2402 }
2403 if (l < 2)
2404 {
2405 LOG(1, s, t, "Short ppp length %d\n", l);
2406 STAT(tunnel_rx_errors);
2407 return;
2408 }
2409 if (*p & 1)
2410 {
2411 prot = *p++;
2412 l--;
2413 }
2414 else
2415 {
2416 prot = ntohs(*(uint16_t *) p);
2417 p += 2;
2418 l -= 2;
2419 }
2420
2421 if (s && !session[s].opened) // Is something wrong??
2422 {
2423 if (!config->cluster_iam_master)
2424 {
2425 // Pass it off to the master to deal with..
2426 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2427 return;
2428 }
2429
2430
2431 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2432 STAT(tunnel_rx_errors);
2433 return;
2434 }
2435
2436 if (prot == PPPPAP)
2437 {
2438 session[s].last_packet = time_now;
2439 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2440 processpap(t, s, p, l);
2441 }
2442 else if (prot == PPPCHAP)
2443 {
2444 session[s].last_packet = time_now;
2445 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2446 processchap(t, s, p, l);
2447 }
2448 else if (prot == PPPLCP)
2449 {
2450 session[s].last_packet = time_now;
2451 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2452 processlcp(t, s, p, l);
2453 }
2454 else if (prot == PPPIPCP)
2455 {
2456 session[s].last_packet = time_now;
2457 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2458 processipcp(t, s, p, l);
2459 }
2460 else if (prot == PPPIPV6CP)
2461 {
2462 if (config->ipv6_prefix.s6_addr[0] > 0)
2463 {
2464 session[s].last_packet = time_now;
2465 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2466 processipv6cp(t, s, p, l);
2467 }
2468 else
2469 {
2470 LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
2471 }
2472 }
2473 else if (prot == PPPCCP)
2474 {
2475 session[s].last_packet = time_now;
2476 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2477 processccp(t, s, p, l);
2478 }
2479 else if (prot == PPPIP)
2480 {
2481 if (session[s].die)
2482 {
2483 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2484 return; // closing session, PPP not processed
2485 }
2486
2487 session[s].last_packet = time_now;
2488 if (session[s].walled_garden && !config->cluster_iam_master)
2489 {
2490 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2491 return;
2492 }
2493
2494 processipin(t, s, p, l);
2495 }
2496 else if (prot == PPPIPV6)
2497 {
2498 if (!config->ipv6_prefix.s6_addr[0] > 0)
2499 {
2500 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2501 return;
2502 }
2503 if (session[s].die)
2504 {
2505 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2506 return; // closing session, PPP not processed
2507 }
2508
2509 session[s].last_packet = time_now;
2510 if (session[s].walled_garden && !config->cluster_iam_master)
2511 {
2512 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2513 return;
2514 }
2515
2516 processipv6in(t, s, p, l);
2517 }
2518 else
2519 {
2520 STAT(tunnel_rx_errors);
2521 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2522 }
2523 }
2524 }
2525
2526 // read and process packet on tun
2527 static void processtun(uint8_t * buf, int len)
2528 {
2529 LOG_HEX(5, "Receive TUN Data", buf, len);
2530 STAT(tun_rx_packets);
2531 INC_STAT(tun_rx_bytes, len);
2532
2533 CSTAT(processtun);
2534
2535 eth_rx_pkt++;
2536 eth_rx += len;
2537 if (len < 22)
2538 {
2539 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2540 STAT(tun_rx_errors);
2541 return;
2542 }
2543
2544 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2545 processipout(buf, len);
2546 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2547 && config->ipv6_prefix.s6_addr[0] > 0)
2548 processipv6out(buf, len);
2549
2550 // Else discard.
2551 }
2552
2553 //
2554 // Maximum number of actions to complete.
2555 // This is to avoid sending out too many packets
2556 // at once.
2557 #define MAX_ACTIONS 500
2558
2559 static int regular_cleanups(void)
2560 {
2561 static sessionidt s = 0; // Next session to check for actions on.
2562 tunnelidt t;
2563 int count=0,i;
2564 uint16_t r;
2565 static clockt next_acct = 0;
2566 static clockt next_shut_acct = 0;
2567 int a;
2568
2569 LOG(3, 0, 0, "Begin regular cleanup\n");
2570
2571 for (r = 1; r < MAXRADIUS; r++)
2572 {
2573 if (!radius[r].state)
2574 continue;
2575 if (radius[r].retry)
2576 {
2577 if (radius[r].retry <= TIME)
2578 radiusretry(r);
2579 } else
2580 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
2581 }
2582 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
2583 {
2584 // check for expired tunnels
2585 if (tunnel[t].die && tunnel[t].die <= TIME)
2586 {
2587 STAT(tunnel_timeout);
2588 tunnelkill(t, "Expired");
2589 continue;
2590 }
2591 // check for message resend
2592 if (tunnel[t].retry && tunnel[t].controlc)
2593 {
2594 // resend pending messages as timeout on reply
2595 if (tunnel[t].retry <= TIME)
2596 {
2597 controlt *c = tunnel[t].controls;
2598 uint8_t w = tunnel[t].window;
2599 tunnel[t].try++; // another try
2600 if (tunnel[t].try > 5)
2601 tunnelkill(t, "Timeout on control message"); // game over
2602 else
2603 while (c && w--)
2604 {
2605 tunnelsend(c->buf, c->length, t);
2606 c = c->next;
2607 }
2608 }
2609 }
2610 // Send hello
2611 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2612 {
2613 controlt *c = controlnew(6); // sending HELLO
2614 controladd(c, t, 0); // send the message
2615 LOG(3, 0, t, "Sending HELLO message\n");
2616 }
2617
2618 // Check for tunnel changes requested from the CLI
2619 if ((a = cli_tunnel_actions[t].action))
2620 {
2621 cli_tunnel_actions[t].action = 0;
2622 if (a & CLI_TUN_KILL)
2623 {
2624 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2625 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2626 }
2627 }
2628
2629 }
2630
2631 count = 0;
2632 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2633 {
2634 s++;
2635 if (s > config->cluster_highest_sessionid)
2636 s = 1;
2637
2638 if (!session[s].opened) // Session isn't in use
2639 continue;
2640
2641 // check for expired sessions
2642 if (session[s].die)
2643 {
2644 if (session[s].die <= TIME)
2645 {
2646 sessionkill(s, "Expired");
2647 if (++count >= MAX_ACTIONS) break;
2648 }
2649 continue;
2650 }
2651
2652 if (session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2653 {
2654 // IPCP has not completed yet. Resend
2655 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2656 sendipcp(session[s].tunnel, s);
2657 }
2658
2659 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2660 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2661 {
2662 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2663 STAT(session_timeout);
2664 if (++count >= MAX_ACTIONS) break;
2665 continue;
2666 }
2667
2668 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2669 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2670 {
2671 uint8_t b[MAXCONTROL] = {0};
2672
2673 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2674 if (!q) continue;
2675
2676 *q = EchoReq;
2677 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2678 *(uint16_t *)(q + 2) = htons(8); // Length
2679 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2680
2681 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2682 (int)(time_now - session[s].last_packet));
2683 tunnelsend(b, 24, session[s].tunnel); // send it
2684 if (++count >= MAX_ACTIONS) break;
2685 }
2686
2687 // Check for actions requested from the CLI
2688 if ((a = cli_session_actions[s].action))
2689 {
2690 int send = 0;
2691
2692 cli_session_actions[s].action = 0;
2693 if (a & CLI_SESS_KILL)
2694 {
2695 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2696 sessionshutdown(s, "Requested by administrator.", 3, 0);
2697 a = 0; // dead, no need to check for other actions
2698 }
2699
2700 if (a & CLI_SESS_NOSNOOP)
2701 {
2702 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2703 session[s].snoop_ip = 0;
2704 session[s].snoop_port = 0;
2705 send++;
2706 }
2707 else if (a & CLI_SESS_SNOOP)
2708 {
2709 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2710 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2711 cli_session_actions[s].snoop_port);
2712
2713 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2714 session[s].snoop_port = cli_session_actions[s].snoop_port;
2715 send++;
2716 }
2717
2718 if (a & CLI_SESS_NOTHROTTLE)
2719 {
2720 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2721 throttle_session(s, 0, 0);
2722 send++;
2723 }
2724 else if (a & CLI_SESS_THROTTLE)
2725 {
2726 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2727 cli_session_actions[s].throttle_in,
2728 cli_session_actions[s].throttle_out);
2729
2730 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2731 send++;
2732 }
2733
2734 if (a & CLI_SESS_NOFILTER)
2735 {
2736 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2737 filter_session(s, 0, 0);
2738 send++;
2739 }
2740 else if (a & CLI_SESS_FILTER)
2741 {
2742 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2743 cli_session_actions[s].filter_in,
2744 cli_session_actions[s].filter_out);
2745
2746 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2747 send++;
2748 }
2749
2750 if (send)
2751 cluster_send_session(s);
2752
2753 if (++count >= MAX_ACTIONS) break;
2754 }
2755
2756 // RADIUS interim accounting
2757 if (config->radius_accounting && config->radius_interim > 0
2758 && session[s].ip && !session[s].walled_garden
2759 && !sess_local[s].radius // RADIUS already in progress
2760 && time_now - sess_local[s].last_interim >= config->radius_interim)
2761 {
2762 if (!(r = radiusnew(s)))
2763 {
2764 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2765 STAT(radius_overflow);
2766 continue;
2767 }
2768
2769 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2770 session[s].user, session[s].unique_id);
2771
2772 radiussend(r, RADIUSINTERIM);
2773 sess_local[s].last_interim = time_now;
2774
2775 if (++count >= MAX_ACTIONS)
2776 break;
2777 }
2778 }
2779
2780 if (*config->accounting_dir)
2781 {
2782 if (next_acct <= TIME)
2783 {
2784 // Dump accounting data
2785 next_acct = TIME + ACCT_TIME;
2786 next_shut_acct = TIME + ACCT_SHUT_TIME;
2787 dump_acct_info(1);
2788 }
2789 else if (next_shut_acct <= TIME)
2790 {
2791 // Dump accounting data for shutdown sessions
2792 next_shut_acct = TIME + ACCT_SHUT_TIME;
2793 if (shut_acct_n)
2794 dump_acct_info(0);
2795 }
2796 }
2797
2798 if (count >= MAX_ACTIONS)
2799 return 1; // Didn't finish!
2800
2801 LOG(3, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2802 return 0;
2803 }
2804
2805
2806 //
2807 // Are we in the middle of a tunnel update, or radius
2808 // requests??
2809 //
2810 static int still_busy(void)
2811 {
2812 int i;
2813 static clockt last_talked = 0;
2814 static clockt start_busy_wait = 0;
2815 if (start_busy_wait == 0)
2816 start_busy_wait = TIME;
2817
2818 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2819 {
2820 if (!tunnel[i].controlc)
2821 continue;
2822
2823 if (last_talked != TIME)
2824 {
2825 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2826 last_talked = TIME;
2827 }
2828 return 1;
2829 }
2830
2831 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2832 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2833 {
2834 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2835 return 0;
2836 }
2837
2838 for (i = 1; i < MAXRADIUS; i++)
2839 {
2840 if (radius[i].state == RADIUSNULL)
2841 continue;
2842 if (radius[i].state == RADIUSWAIT)
2843 continue;
2844
2845 if (last_talked != TIME)
2846 {
2847 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2848 last_talked = TIME;
2849 }
2850 return 1;
2851 }
2852
2853 return 0;
2854 }
2855
2856 static fd_set readset;
2857 static int readset_n = 0;
2858
2859 // main loop - gets packets on tun or udp and processes them
2860 static void mainloop(void)
2861 {
2862 int i;
2863 uint8_t buf[65536];
2864 struct timeval to;
2865 clockt next_cluster_ping = 0; // send initial ping immediately
2866 time_t next_clean = time_now + config->cleanup_interval;
2867
2868 LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2869 udpfd, tunfd, cluster_sockfd, controlfd);
2870
2871 FD_ZERO(&readset);
2872 FD_SET(udpfd, &readset);
2873 FD_SET(tunfd, &readset);
2874 FD_SET(controlfd, &readset);
2875 FD_SET(clifd, &readset);
2876 if (cluster_sockfd) FD_SET(cluster_sockfd, &readset);
2877 readset_n = udpfd;
2878 if (tunfd > readset_n) readset_n = tunfd;
2879 if (controlfd > readset_n) readset_n = controlfd;
2880 if (clifd > readset_n) readset_n = clifd;
2881 if (cluster_sockfd > readset_n) readset_n = cluster_sockfd;
2882
2883 while (!main_quit || still_busy())
2884 {
2885 fd_set r;
2886 int n = readset_n;
2887 #ifdef BGP
2888 fd_set w;
2889 int bgp_set[BGP_NUM_PEERS];
2890 #endif /* BGP */
2891
2892 if (config->reload_config)
2893 {
2894 // Update the config state based on config settings
2895 update_config();
2896 }
2897
2898 memcpy(&r, &readset, sizeof(fd_set));
2899 to.tv_sec = 0;
2900 to.tv_usec = 100000; // 1/10th of a second.
2901
2902 #ifdef BGP
2903 FD_ZERO(&w);
2904 for (i = 0; i < BGP_NUM_PEERS; i++)
2905 {
2906 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2907 if (bgp_set[i] & 1)
2908 {
2909 FD_SET(bgp_peers[i].sock, &r);
2910 if (bgp_peers[i].sock > n)
2911 n = bgp_peers[i].sock;
2912 }
2913
2914 if (bgp_set[i] & 2)
2915 {
2916 FD_SET(bgp_peers[i].sock, &w);
2917 if (bgp_peers[i].sock > n)
2918 n = bgp_peers[i].sock;
2919 }
2920 }
2921
2922 n = select(n + 1, &r, &w, 0, &to);
2923 #else /* BGP */
2924 n = select(n + 1, &r, 0, 0, &to);
2925 #endif /* BGP */
2926
2927 STAT(select_called);
2928
2929 TIME = now();
2930 if (n < 0)
2931 {
2932 if (errno == EINTR ||
2933 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
2934 continue;
2935
2936 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2937 main_quit++;
2938 break;
2939 }
2940 else if (n)
2941 {
2942 struct sockaddr_in addr;
2943 int alen, c, s;
2944 int udp_pkts = 0;
2945 int tun_pkts = 0;
2946 int cluster_pkts = 0;
2947
2948 // nsctl commands
2949 if (FD_ISSET(controlfd, &r))
2950 {
2951 alen = sizeof(addr);
2952 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
2953 n--;
2954 }
2955
2956 // RADIUS responses
2957 if (config->cluster_iam_master)
2958 {
2959 for (i = 0; i < config->num_radfds; i++)
2960 {
2961 if (FD_ISSET(radfds[i], &r))
2962 {
2963 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2964 n--;
2965 }
2966 }
2967 }
2968
2969 // CLI connections
2970 if (FD_ISSET(clifd, &r))
2971 {
2972 int cli;
2973
2974 alen = sizeof(addr);
2975 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
2976 {
2977 cli_do(cli);
2978 close(cli);
2979 }
2980 else
2981 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
2982
2983 n--;
2984 }
2985
2986 #ifdef BGP
2987 for (i = 0; i < BGP_NUM_PEERS; i++)
2988 {
2989 int isr = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0;
2990 int isw = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0;
2991 bgp_process(&bgp_peers[i], isr, isw);
2992 if (isr) n--;
2993 if (isw) n--;
2994 }
2995 #endif /* BGP */
2996
2997 for (c = 0; n && c < config->multi_read_count; c++)
2998 {
2999 // L2TP
3000 if (FD_ISSET(udpfd, &r))
3001 {
3002 alen = sizeof(addr);
3003 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3004 {
3005 processudp(buf, s, &addr);
3006 udp_pkts++;
3007 }
3008 else
3009 {
3010 FD_CLR(udpfd, &r);
3011 n--;
3012 }
3013 }
3014
3015 // incoming IP
3016 if (FD_ISSET(tunfd, &r))
3017 {
3018 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3019 {
3020 processtun(buf, s);
3021 tun_pkts++;
3022 }
3023 else
3024 {
3025 FD_CLR(tunfd, &r);
3026 n--;
3027 }
3028 }
3029
3030 // cluster
3031 if (FD_ISSET(cluster_sockfd, &r))
3032 {
3033 alen = sizeof(addr);
3034 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3035 {
3036 processcluster(buf, s, addr.sin_addr.s_addr);
3037 cluster_pkts++;
3038 }
3039 else
3040 {
3041 FD_CLR(cluster_sockfd, &r);
3042 n--;
3043 }
3044 }
3045 }
3046
3047 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3048 STAT(multi_read_used);
3049
3050 if (c >= config->multi_read_count)
3051 {
3052 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3053 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3054
3055 STAT(multi_read_exceeded);
3056 }
3057 }
3058
3059 // Runs on every machine (master and slaves).
3060 if (cluster_sockfd && next_cluster_ping <= TIME)
3061 {
3062 // Check to see which of the cluster is still alive..
3063
3064 cluster_send_ping(basetime); // Only does anything if we're a slave
3065 cluster_check_master(); // ditto.
3066
3067 cluster_heartbeat(); // Only does anything if we're a master.
3068 cluster_check_slaves(); // ditto.
3069
3070 master_update_counts(); // If we're a slave, send our byte counters to our master.
3071
3072 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3073 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3074 else
3075 next_cluster_ping = TIME + config->cluster_hb_interval;
3076 }
3077
3078 // Run token bucket filtering queue..
3079 // Only run it every 1/10th of a second.
3080 // Runs on all machines both master and slave.
3081 {
3082 static clockt last_run = 0;
3083 if (last_run != TIME)
3084 {
3085 last_run = TIME;
3086 tbf_run_timer();
3087 }
3088 }
3089
3090 /* Handle timeouts. Make sure that this gets run anyway, even if there was
3091 * something to read, else under load this will never actually run....
3092 *
3093 */
3094 if (config->cluster_iam_master && next_clean <= time_now)
3095 {
3096 if (regular_cleanups())
3097 {
3098 // Did it finish?
3099 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
3100 }
3101 else
3102 {
3103 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
3104 }
3105 }
3106 }
3107
3108 // Are we the master and shutting down??
3109 if (config->cluster_iam_master)
3110 cluster_heartbeat(); // Flush any queued changes..
3111
3112 // Ok. Notify everyone we're shutting down. If we're
3113 // the master, this will force an election.
3114 cluster_send_ping(0);
3115
3116 //
3117 // Important!!! We MUST not process any packets past this point!
3118 }
3119
3120 static void stripdomain(char *host)
3121 {
3122 char *p;
3123
3124 if ((p = strchr(host, '.')))
3125 {
3126 char *domain = 0;
3127 char _domain[1024];
3128
3129 // strip off domain
3130 FILE *resolv = fopen("/etc/resolv.conf", "r");
3131 if (resolv)
3132 {
3133 char buf[1024];
3134 char *b;
3135
3136 while (fgets(buf, sizeof(buf), resolv))
3137 {
3138 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3139 continue;
3140
3141 if (!isspace(buf[6]))
3142 continue;
3143
3144 b = buf + 7;
3145 while (isspace(*b)) b++;
3146
3147 if (*b)
3148 {
3149 char *d = b;
3150 while (*b && !isspace(*b)) b++;
3151 *b = 0;
3152 if (buf[0] == 'd') // domain is canonical
3153 {
3154 domain = d;
3155 break;
3156 }
3157
3158 // first search line
3159 if (!domain)
3160 {
3161 // hold, may be subsequent domain line
3162 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3163 domain = _domain;
3164 }
3165 }
3166 }
3167
3168 fclose(resolv);
3169 }
3170
3171 if (domain)
3172 {
3173 int hl = strlen(host);
3174 int dl = strlen(domain);
3175 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3176 host[hl -dl - 1] = 0;
3177 }
3178 else
3179 {
3180 *p = 0; // everything after first dot
3181 }
3182 }
3183 }
3184
3185 // Init data structures
3186 static void initdata(int optdebug, char *optconfig)
3187 {
3188 int i;
3189
3190 if (!(config = shared_malloc(sizeof(configt))))
3191 {
3192 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3193 exit(1);
3194 }
3195
3196 memset(config, 0, sizeof(configt));
3197 time(&config->start_time);
3198 strncpy(config->config_file, optconfig, strlen(optconfig));
3199 config->debug = optdebug;
3200 config->num_tbfs = MAXTBFS;
3201 config->rl_rate = 28; // 28kbps
3202 strcpy(config->random_device, RANDOMDEVICE);
3203
3204 log_stream = stderr;
3205
3206 #ifdef RINGBUFFER
3207 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3208 {
3209 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3210 exit(1);
3211 }
3212 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3213 #endif
3214
3215 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3216 {
3217 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3218 exit(1);
3219 }
3220 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3221 {
3222 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3223 exit(1);
3224 }
3225 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3226 {
3227 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3228 exit(1);
3229 }
3230
3231 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3232 {
3233 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3234 exit(1);
3235 }
3236
3237 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3238 {
3239 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3240 exit(1);
3241 }
3242
3243 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3244 {
3245 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3246 exit(1);
3247 }
3248
3249 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3250 {
3251 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3252 exit(1);
3253 }
3254 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3255
3256 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3257 {
3258 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3259 exit(1);
3260 }
3261 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3262
3263 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3264 {
3265 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3266 exit(1);
3267 }
3268 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3269
3270 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3271 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3272 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3273 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3274
3275 // Put all the sessions on the free list marked as undefined.
3276 for (i = 1; i < MAXSESSION; i++)
3277 {
3278 session[i].next = i + 1;
3279 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3280 }
3281 session[MAXSESSION - 1].next = 0;
3282 sessionfree = 1;
3283
3284 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3285 for (i = 1; i < MAXTUNNEL; i++)
3286 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3287
3288 if (!*hostname)
3289 {
3290 // Grab my hostname unless it's been specified
3291 gethostname(hostname, sizeof(hostname));
3292 stripdomain(hostname);
3293 }
3294
3295 _statistics->start_time = _statistics->last_reset = time(NULL);
3296
3297 #ifdef BGP
3298 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3299 {
3300 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3301 exit(1);
3302 }
3303 #endif /* BGP */
3304 }
3305
3306 static int assign_ip_address(sessionidt s)
3307 {
3308 uint32_t i;
3309 int best = -1;
3310 time_t best_time = time_now;
3311 char *u = session[s].user;
3312 char reuse = 0;
3313
3314
3315 CSTAT(assign_ip_address);
3316
3317 for (i = 1; i < ip_pool_size; i++)
3318 {
3319 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3320 continue;
3321
3322 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3323 {
3324 best = i;
3325 reuse = 1;
3326 break;
3327 }
3328
3329 if (ip_address_pool[i].last < best_time)
3330 {
3331 best = i;
3332 if (!(best_time = ip_address_pool[i].last))
3333 break; // never used, grab this one
3334 }
3335 }
3336
3337 if (best < 0)
3338 {
3339 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3340 return 0;
3341 }
3342
3343 session[s].ip = ip_address_pool[best].address;
3344 session[s].ip_pool_index = best;
3345 ip_address_pool[best].assigned = 1;
3346 ip_address_pool[best].last = time_now;
3347 ip_address_pool[best].session = s;
3348 if (session[s].walled_garden)
3349 /* Don't track addresses of users in walled garden (note: this
3350 means that their address isn't "sticky" even if they get
3351 un-gardened). */
3352 ip_address_pool[best].user[0] = 0;
3353 else
3354 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3355
3356 STAT(ip_allocated);
3357 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3358 reuse ? "Reusing" : "Allocating", best);
3359
3360 return 1;
3361 }
3362
3363 static void free_ip_address(sessionidt s)
3364 {
3365 int i = session[s].ip_pool_index;
3366
3367
3368 CSTAT(free_ip_address);
3369
3370 if (!session[s].ip)
3371 return; // what the?
3372
3373 if (i < 0) // Is this actually part of the ip pool?
3374 i = 0;
3375
3376 STAT(ip_freed);
3377 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3378 session[s].ip = 0;
3379 ip_address_pool[i].assigned = 0;
3380 ip_address_pool[i].session = 0;
3381 ip_address_pool[i].last = time_now;
3382 }
3383
3384 //
3385 // Fsck the address pool against the session table.
3386 // Normally only called when we become a master.
3387 //
3388 // This isn't perfect: We aren't keep tracking of which
3389 // users used to have an IP address.
3390 //
3391 void rebuild_address_pool(void)
3392 {
3393 int i;
3394
3395 //
3396 // Zero the IP pool allocation, and build
3397 // a map from IP address to pool index.
3398 for (i = 1; i < MAXIPPOOL; ++i)
3399 {
3400 ip_address_pool[i].assigned = 0;
3401 ip_address_pool[i].session = 0;
3402 if (!ip_address_pool[i].address)
3403 continue;
3404
3405 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3406 }
3407
3408 for (i = 0; i < MAXSESSION; ++i)
3409 {
3410 int ipid;
3411 if (!(session[i].opened && session[i].ip))
3412 continue;
3413
3414 ipid = - lookup_ipmap(htonl(session[i].ip));
3415
3416 if (session[i].ip_pool_index < 0)
3417 {
3418 // Not allocated out of the pool.
3419 if (ipid < 1) // Not found in the pool either? good.
3420 continue;
3421
3422 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3423 i, fmtaddr(session[i].ip, 0), ipid);
3424
3425 // Fall through and process it as part of the pool.
3426 }
3427
3428
3429 if (ipid > MAXIPPOOL || ipid < 0)
3430 {
3431 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3432 ipid = -1;
3433 session[i].ip_pool_index = ipid;
3434 continue;
3435 }
3436
3437 ip_address_pool[ipid].assigned = 1;
3438 ip_address_pool[ipid].session = i;
3439 ip_address_pool[ipid].last = time_now;
3440 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3441 session[i].ip_pool_index = ipid;
3442 cache_ipmap(session[i].ip, i); // Fix the ip map.
3443 }
3444 }
3445
3446 //
3447 // Fix the address pool to match a changed session.
3448 // (usually when the master sends us an update).
3449 static void fix_address_pool(int sid)
3450 {
3451 int ipid;
3452
3453 ipid = session[sid].ip_pool_index;
3454
3455 if (ipid > ip_pool_size)
3456 return; // Ignore it. rebuild_address_pool will fix it up.
3457
3458 if (ip_address_pool[ipid].address != session[sid].ip)
3459 return; // Just ignore it. rebuild_address_pool will take care of it.
3460
3461 ip_address_pool[ipid].assigned = 1;
3462 ip_address_pool[ipid].session = sid;
3463 ip_address_pool[ipid].last = time_now;
3464 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3465 }
3466
3467 //
3468 // Add a block of addresses to the IP pool to hand out.
3469 //
3470 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3471 {
3472 int i;
3473 if (mask == 0)
3474 mask = 0xffffffff; // Host route only.
3475
3476 addr &= mask;
3477
3478 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3479 return ;
3480
3481 for (i = addr ;(i & mask) == addr; ++i)
3482 {
3483 if ((i & 0xff) == 0 || (i&0xff) == 255)
3484 continue; // Skip 0 and broadcast addresses.
3485
3486 ip_address_pool[ip_pool_size].address = i;
3487 ip_address_pool[ip_pool_size].assigned = 0;
3488 ++ip_pool_size;
3489 if (ip_pool_size >= MAXIPPOOL)
3490 {
3491 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3492 return;
3493 }
3494 }
3495 }
3496
3497 // Initialize the IP address pool
3498 static void initippool()
3499 {
3500 FILE *f;
3501 char *p;
3502 char buf[4096];
3503 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3504
3505 if (!(f = fopen(IPPOOLFILE, "r")))
3506 {
3507 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3508 exit(1);
3509 }
3510
3511 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3512 {
3513 char *pool = buf;
3514 buf[4095] = 0; // Force it to be zero terminated/
3515
3516 if (*buf == '#' || *buf == '\n')
3517 continue; // Skip comments / blank lines
3518 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3519 if ((p = (char *)strchr(buf, ':')))
3520 {
3521 in_addr_t src;
3522 *p = '\0';
3523 src = inet_addr(buf);
3524 if (src == INADDR_NONE)
3525 {
3526 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3527 exit(1);
3528 }
3529 // This entry is for a specific IP only
3530 if (src != config->bind_address)
3531 continue;
3532 *p = ':';
3533 pool = p+1;
3534 }
3535 if ((p = (char *)strchr(pool, '/')))
3536 {
3537 // It's a range
3538 int numbits = 0;
3539 in_addr_t start = 0, mask = 0;
3540
3541 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3542 *p++ = 0;
3543 if (!*p || !(numbits = atoi(p)))
3544 {
3545 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3546 continue;
3547 }
3548 start = ntohl(inet_addr(pool));
3549 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3550
3551 // Add a static route for this pool
3552 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3553 fmtaddr(htonl(start), 0), 32 + mask);
3554
3555 routeset(0, start, mask, 0, 1);
3556
3557 add_to_ip_pool(start, mask);
3558 }
3559 else
3560 {
3561 // It's a single ip address
3562 add_to_ip_pool(inet_addr(pool), 0);
3563 }
3564 }
3565 fclose(f);
3566 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3567 }
3568
3569 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
3570 {
3571 struct sockaddr_in snoop_addr = {0};
3572 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3573 return;
3574
3575 snoop_addr.sin_family = AF_INET;
3576 snoop_addr.sin_addr.s_addr = destination;
3577 snoop_addr.sin_port = ntohs(port);
3578
3579 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3580 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3581 htons(snoop_addr.sin_port));
3582
3583 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3584 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3585
3586 STAT(packets_snooped);
3587 }
3588
3589 static int dump_session(FILE **f, sessiont *s)
3590 {
3591 if (!s->opened || !s->ip || !(s->cin || s->cout) || !*s->user || s->walled_garden)
3592 return 1;
3593
3594 if (!*f)
3595 {
3596 char filename[1024];
3597 char timestr[64];
3598 time_t now = time(NULL);
3599
3600 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3601 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3602
3603 if (!(*f = fopen(filename, "w")))
3604 {
3605 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3606 return 0;
3607 }
3608
3609 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3610 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3611 "# host: %s\n"
3612 "# time: %ld\n"
3613 "# uptime: %ld\n"
3614 "# format: username ip qos uptxoctets downrxoctets\n",
3615 hostname,
3616 now,
3617 now - basetime);
3618 }
3619
3620 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3621 fprintf(*f, "%s %s %d %u %u\n",
3622 s->user, // username
3623 fmtaddr(htonl(s->ip), 0), // ip
3624 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3625 (uint32_t) s->cin, // uptxoctets
3626 (uint32_t) s->cout); // downrxoctets
3627
3628 s->pin = s->cin = 0;
3629 s->pout = s->cout = 0;
3630
3631 return 1;
3632 }
3633
3634 static void dump_acct_info(int all)
3635 {
3636 int i;
3637 FILE *f = NULL;
3638
3639
3640 CSTAT(dump_acct_info);
3641
3642 if (shut_acct_n)
3643 {
3644 for (i = 0; i < shut_acct_n; i++)
3645 dump_session(&f, &shut_acct[i]);
3646
3647 shut_acct_n = 0;
3648 }
3649
3650 if (all)
3651 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3652 dump_session(&f, &session[i]);
3653
3654 if (f)
3655 fclose(f);
3656 }
3657
3658 // Main program
3659 int main(int argc, char *argv[])
3660 {
3661 int i;
3662 int optdebug = 0;
3663 char *optconfig = CONFIGFILE;
3664
3665 time(&basetime); // start clock
3666
3667 // scan args
3668 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3669 {
3670 switch (i)
3671 {
3672 case 'd':
3673 if (fork()) exit(0);
3674 setsid();
3675 freopen("/dev/null", "r", stdin);
3676 freopen("/dev/null", "w", stdout);
3677 freopen("/dev/null", "w", stderr);
3678 break;
3679 case 'v':
3680 optdebug++;
3681 break;
3682 case 'c':
3683 optconfig = optarg;
3684 break;
3685 case 'h':
3686 snprintf(hostname, sizeof(hostname), "%s", optarg);
3687 break;
3688 default:
3689 printf("Args are:\n"
3690 "\t-d\t\tDetach from terminal\n"
3691 "\t-c <file>\tConfig file\n"
3692 "\t-h <hostname>\tForce hostname\n"
3693 "\t-v\t\tDebug\n");
3694
3695 return (0);
3696 break;
3697 }
3698 }
3699
3700 // Start the timer routine off
3701 time(&time_now);
3702 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3703 signal(SIGALRM, sigalrm_handler);
3704 siginterrupt(SIGALRM, 0);
3705
3706 initplugins();
3707 initdata(optdebug, optconfig);
3708
3709 init_cli(hostname);
3710 read_config_file();
3711 init_tbf(config->num_tbfs);
3712
3713 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3714 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3715 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3716 {
3717 struct rlimit rlim;
3718 rlim.rlim_cur = RLIM_INFINITY;
3719 rlim.rlim_max = RLIM_INFINITY;
3720 // Remove the maximum core size
3721 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3722 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3723
3724 // Make core dumps go to /tmp
3725 chdir("/tmp");
3726 }
3727
3728 if (config->scheduler_fifo)
3729 {
3730 int ret;
3731 struct sched_param params = {0};
3732 params.sched_priority = 1;
3733
3734 if (get_nprocs() < 2)
3735 {
3736 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3737 config->scheduler_fifo = 0;
3738 }
3739 else
3740 {
3741 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3742 {
3743 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3744 }
3745 else
3746 {
3747 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3748 config->scheduler_fifo = 0;
3749 }
3750 }
3751 }
3752
3753 /* Set up the cluster communications port. */
3754 if (cluster_init() < 0)
3755 exit(1);
3756
3757 #ifdef BGP
3758 signal(SIGPIPE, SIG_IGN);
3759 bgp_setup(config->as_number);
3760 bgp_add_route(config->bind_address, 0xffffffff);
3761 for (i = 0; i < BGP_NUM_PEERS; i++)
3762 {
3763 if (config->neighbour[i].name[0])
3764 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3765 config->neighbour[i].as, config->neighbour[i].keepalive,
3766 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3767 }
3768 #endif /* BGP */
3769
3770 inittun();
3771 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3772
3773 initudp();
3774 initrad();
3775 initippool();
3776
3777 signal(SIGHUP, sighup_handler);
3778 signal(SIGTERM, sigterm_handler);
3779 signal(SIGINT, sigterm_handler);
3780 signal(SIGQUIT, sigquit_handler);
3781 signal(SIGCHLD, sigchild_handler);
3782
3783 // Prevent us from getting paged out
3784 if (config->lock_pages)
3785 {
3786 if (!mlockall(MCL_CURRENT))
3787 LOG(1, 0, 0, "Locking pages into memory\n");
3788 else
3789 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3790 }
3791
3792 alarm(1);
3793
3794 // Drop privileges here
3795 if (config->target_uid > 0 && geteuid() == 0)
3796 setuid(config->target_uid);
3797
3798 mainloop();
3799
3800 #ifdef BGP
3801 /* try to shut BGP down cleanly; with luck the sockets will be
3802 writable since we're out of the select */
3803 for (i = 0; i < BGP_NUM_PEERS; i++)
3804 if (bgp_peers[i].state == Established)
3805 bgp_stop(&bgp_peers[i]);
3806 #endif /* BGP */
3807
3808 /* remove plugins (so cleanup code gets run) */
3809 plugins_done();
3810
3811 // Remove the PID file if we wrote it
3812 if (config->wrote_pid && *config->pid_file == '/')
3813 unlink(config->pid_file);
3814
3815 /* kill CLI children */
3816 signal(SIGTERM, SIG_IGN);
3817 kill(0, SIGTERM);
3818 return 0;
3819 }
3820
3821 static void sighup_handler(int sig)
3822 {
3823 if (log_stream)
3824 {
3825 if (log_stream != stderr)
3826 fclose(log_stream);
3827
3828 log_stream = NULL;
3829 }
3830
3831 read_config_file();
3832 }
3833
3834 static void sigalrm_handler(int sig)
3835 {
3836 // Log current traffic stats
3837
3838 snprintf(config->bandwidth, sizeof(config->bandwidth),
3839 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3840 (udp_rx / 1024.0 / 1024.0 * 8),
3841 (eth_tx / 1024.0 / 1024.0 * 8),
3842 (eth_rx / 1024.0 / 1024.0 * 8),
3843 (udp_tx / 1024.0 / 1024.0 * 8),
3844 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3845 udp_rx_pkt, eth_rx_pkt);
3846
3847 udp_tx = udp_rx = 0;
3848 udp_rx_pkt = eth_rx_pkt = 0;
3849 eth_tx = eth_rx = 0;
3850
3851 if (config->dump_speed)
3852 printf("%s\n", config->bandwidth);
3853
3854 // Update the internal time counter
3855 time(&time_now);
3856 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3857 alarm(1);
3858
3859 {
3860 // Run timer hooks
3861 struct param_timer p = { time_now };
3862 run_plugins(PLUGIN_TIMER, &p);
3863 }
3864
3865 }
3866
3867 static void sigterm_handler(int sig)
3868 {
3869 LOG(1, 0, 0, "Shutting down cleanly\n");
3870 main_quit++;
3871 }
3872
3873 static void sigquit_handler(int sig)
3874 {
3875 int i;
3876
3877 LOG(1, 0, 0, "Shutting down without saving sessions\n");
3878
3879 if (config->cluster_iam_master)
3880 {
3881 for (i = 1; i < MAXSESSION; i++)
3882 {
3883 if (session[i].opened)
3884 sessionkill(i, "L2TPNS Closing");
3885 }
3886 for (i = 1; i < MAXTUNNEL; i++)
3887 {
3888 if (tunnel[i].ip || tunnel[i].state)
3889 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3890 }
3891 }
3892
3893 main_quit++;
3894 }
3895
3896 static void sigchild_handler(int sig)
3897 {
3898 while (waitpid(-1, NULL, WNOHANG) > 0)
3899 ;
3900 }
3901
3902 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
3903 {
3904 MD5_CTX ctx;
3905 *challenge_response = NULL;
3906
3907 if (!*config->l2tpsecret)
3908 {
3909 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3910 return;
3911 }
3912
3913 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
3914
3915 *challenge_response = (char *)calloc(17, 1);
3916
3917 MD5Init(&ctx);
3918 MD5Update(&ctx, &id, 1);
3919 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3920 MD5Update(&ctx, challenge, challenge_length);
3921 MD5Final(*challenge_response, &ctx);
3922
3923 return;
3924 }
3925
3926 static int facility_value(char *name)
3927 {
3928 int i;
3929 for (i = 0; facilitynames[i].c_name; i++)
3930 {
3931 if (strcmp(facilitynames[i].c_name, name) == 0)
3932 return facilitynames[i].c_val;
3933 }
3934 return 0;
3935 }
3936
3937 static void update_config()
3938 {
3939 int i;
3940 char *p;
3941 static int timeout = 0;
3942 static int interval = 0;
3943
3944 // Update logging
3945 closelog();
3946 syslog_log = 0;
3947 if (log_stream)
3948 {
3949 if (log_stream != stderr)
3950 fclose(log_stream);
3951
3952 log_stream = NULL;
3953 }
3954
3955 if (*config->log_filename)
3956 {
3957 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3958 {
3959 char *p = config->log_filename + 7;
3960 if (*p)
3961 {
3962 openlog("l2tpns", LOG_PID, facility_value(p));
3963 syslog_log = 1;
3964 }
3965 }
3966 else if (strchr(config->log_filename, '/') == config->log_filename)
3967 {
3968 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3969 {
3970 fseek(log_stream, 0, SEEK_END);
3971 setbuf(log_stream, NULL);
3972 }
3973 else
3974 {
3975 log_stream = stderr;
3976 setbuf(log_stream, NULL);
3977 }
3978 }
3979 }
3980 else
3981 {
3982 log_stream = stderr;
3983 setbuf(log_stream, NULL);
3984 }
3985
3986 // Update radius
3987 config->numradiusservers = 0;
3988 for (i = 0; i < MAXRADSERVER; i++)
3989 if (config->radiusserver[i])
3990 {
3991 config->numradiusservers++;
3992 // Set radius port: if not set, take the port from the
3993 // first radius server. For the first radius server,
3994 // take the #defined default value from l2tpns.h
3995
3996 // test twice, In case someone works with
3997 // a secondary radius server without defining
3998 // a primary one, this will work even then.
3999 if (i > 0 && !config->radiusport[i])
4000 config->radiusport[i] = config->radiusport[i-1];
4001 if (!config->radiusport[i])
4002 config->radiusport[i] = RADPORT;
4003 }
4004
4005 if (!config->numradiusservers)
4006 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4007
4008 config->num_radfds = 1 << RADIUS_SHIFT;
4009
4010 // parse radius_authtypes_s
4011 config->radius_authtypes = config->radius_authprefer = 0;
4012 p = config->radius_authtypes_s;
4013 while (p && *p)
4014 {
4015 char *s = strpbrk(p, " \t,");
4016 int type = 0;
4017
4018 if (s)
4019 {
4020 *s++ = 0;
4021 while (*s == ' ' || *s == '\t')
4022 s++;
4023
4024 if (!*s)
4025 s = 0;
4026 }
4027
4028 if (!strncasecmp("chap", p, strlen(p)))
4029 type = AUTHCHAP;
4030 else if (!strncasecmp("pap", p, strlen(p)))
4031 type = AUTHPAP;
4032 else
4033 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4034
4035 config->radius_authtypes |= type;
4036 if (!config->radius_authprefer)
4037 config->radius_authprefer = type;
4038
4039 p = s;
4040 }
4041
4042 if (!config->radius_authtypes)
4043 {
4044 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4045 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4046 }
4047
4048 // normalise radius_authtypes_s
4049 if (config->radius_authprefer == AUTHPAP)
4050 {
4051 strcpy(config->radius_authtypes_s, "pap");
4052 if (config->radius_authtypes & AUTHCHAP)
4053 strcat(config->radius_authtypes_s, ", chap");
4054 }
4055 else
4056 {
4057 strcpy(config->radius_authtypes_s, "chap");
4058 if (config->radius_authtypes & AUTHPAP)
4059 strcat(config->radius_authtypes_s, ", pap");
4060 }
4061
4062 // re-initialise the random number source
4063 initrandom(config->random_device);
4064
4065 // Update plugins
4066 for (i = 0; i < MAXPLUGINS; i++)
4067 {
4068 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4069 continue;
4070
4071 if (*config->plugins[i])
4072 {
4073 // Plugin added
4074 add_plugin(config->plugins[i]);
4075 }
4076 else if (*config->old_plugins[i])
4077 {
4078 // Plugin removed
4079 remove_plugin(config->old_plugins[i]);
4080 }
4081 }
4082
4083 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4084 if (!config->cleanup_interval) config->cleanup_interval = 10;
4085 if (!config->multi_read_count) config->multi_read_count = 10;
4086 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4087 if (!*config->cluster_interface)
4088 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4089
4090 if (!config->cluster_hb_interval)
4091 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4092
4093 if (!config->cluster_hb_timeout)
4094 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4095
4096 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4097 {
4098 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4099 // late, ensure we're sufficiently larger than that
4100 int t = 4 * config->cluster_hb_interval + 11;
4101
4102 if (config->cluster_hb_timeout < t)
4103 {
4104 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4105 config->cluster_hb_timeout = t;
4106 }
4107
4108 // Push timing changes to the slaves immediately if we're the master
4109 if (config->cluster_iam_master)
4110 cluster_heartbeat();
4111
4112 interval = config->cluster_hb_interval;
4113 timeout = config->cluster_hb_timeout;
4114 }
4115
4116 // Write PID file
4117 if (*config->pid_file == '/' && !config->wrote_pid)
4118 {
4119 FILE *f;
4120 if ((f = fopen(config->pid_file, "w")))
4121 {
4122 fprintf(f, "%d\n", getpid());
4123 fclose(f);
4124 config->wrote_pid = 1;
4125 }
4126 else
4127 {
4128 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4129 }
4130 }
4131
4132 config->reload_config = 0;
4133 }
4134
4135 static void read_config_file()
4136 {
4137 FILE *f;
4138
4139 if (!config->config_file) return;
4140 if (!(f = fopen(config->config_file, "r")))
4141 {
4142 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4143 return;
4144 }
4145
4146 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4147 cli_do_file(f);
4148 LOG(3, 0, 0, "Done reading config file\n");
4149 fclose(f);
4150 update_config();
4151 }
4152
4153 int sessionsetup(tunnelidt t, sessionidt s)
4154 {
4155 // A session now exists, set it up
4156 in_addr_t ip;
4157 char *user;
4158 sessionidt i;
4159 int r;
4160
4161 CSTAT(sessionsetup);
4162
4163 LOG(3, s, t, "Doing session setup for session\n");
4164
4165 if (!session[s].ip)
4166 {
4167 assign_ip_address(s);
4168 if (!session[s].ip)
4169 {
4170 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4171 sessionshutdown(s, "No IP addresses available.", 2, 7);
4172 return 0;
4173 }
4174 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4175 fmtaddr(htonl(session[s].ip), 0));
4176 }
4177
4178
4179 // Make sure this is right
4180 session[s].tunnel = t;
4181
4182 // zap old sessions with same IP and/or username
4183 // Don't kill gardened sessions - doing so leads to a DoS
4184 // from someone who doesn't need to know the password
4185 {
4186 ip = session[s].ip;
4187 user = session[s].user;
4188 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4189 {
4190 if (i == s) continue;
4191 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
4192 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
4193 sessionkill(i, "Duplicate session for users");
4194 }
4195 }
4196
4197 {
4198 int routed = 0;
4199
4200 // Add the route for this session.
4201 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4202 {
4203 if ((session[s].ip & session[s].route[r].mask) ==
4204 (session[s].route[r].ip & session[s].route[r].mask))
4205 routed++;
4206
4207 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4208 }
4209
4210 // Static IPs need to be routed if not already
4211 // convered by a Framed-Route. Anything else is part
4212 // of the IP address pool and is already routed, it
4213 // just needs to be added to the IP cache.
4214 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4215 if (session[s].ip_pool_index == -1) // static ip
4216 {
4217 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4218 }
4219 else
4220 cache_ipmap(session[s].ip, s);
4221 }
4222
4223 if (!session[s].unique_id)
4224 {
4225 // did this session just finish radius?
4226 LOG(3, s, t, "Sending initial IPCP to client\n");
4227 sendipcp(t, s);
4228 session[s].unique_id = ++last_id;
4229 }
4230
4231 // Run the plugin's against this new session.
4232 {
4233 struct param_new_session data = { &tunnel[t], &session[s] };
4234 run_plugins(PLUGIN_NEW_SESSION, &data);
4235 }
4236
4237 // Allocate TBFs if throttled
4238 if (session[s].throttle_in || session[s].throttle_out)
4239 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4240
4241 session[s].last_packet = time_now;
4242
4243 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4244 fmtaddr(htonl(session[s].ip), 0),
4245 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4246
4247 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4248
4249 return 1; // RADIUS OK and IP allocated, done...
4250 }
4251
4252 //
4253 // This session just got dropped on us by the master or something.
4254 // Make sure our tables up up to date...
4255 //
4256 int load_session(sessionidt s, sessiont *new)
4257 {
4258 int i;
4259 int newip = 0;
4260
4261 // Sanity checks.
4262 if (new->ip_pool_index >= MAXIPPOOL ||
4263 new->tunnel >= MAXTUNNEL)
4264 {
4265 LOG(0, s, 0, "Strange session update received!\n");
4266 // FIXME! What to do here?
4267 return 0;
4268 }
4269
4270 //
4271 // Ok. All sanity checks passed. Now we're committed to
4272 // loading the new session.
4273 //
4274
4275 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4276
4277 // See if routes/ip cache need updating
4278 if (new->ip != session[s].ip)
4279 newip++;
4280
4281 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4282 if (new->route[i].ip != session[s].route[i].ip ||
4283 new->route[i].mask != session[s].route[i].mask)
4284 newip++;
4285
4286 // needs update
4287 if (newip)
4288 {
4289 int routed = 0;
4290
4291 // remove old routes...
4292 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4293 {
4294 if ((session[s].ip & session[s].route[i].mask) ==
4295 (session[s].route[i].ip & session[s].route[i].mask))
4296 routed++;
4297
4298 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4299 }
4300
4301 // ...ip
4302 if (session[s].ip)
4303 {
4304 if (session[s].ip_pool_index == -1) // static IP
4305 {
4306 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4307 }
4308 else // It's part of the IP pool, remove it manually.
4309 uncache_ipmap(session[s].ip);
4310 }
4311
4312 routed = 0;
4313
4314 // add new routes...
4315 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4316 {
4317 if ((new->ip & new->route[i].mask) ==
4318 (new->route[i].ip & new->route[i].mask))
4319 routed++;
4320
4321 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4322 }
4323
4324 // ...ip
4325 if (new->ip)
4326 {
4327 // If there's a new one, add it.
4328 if (new->ip_pool_index == -1)
4329 {
4330 if (!routed) routeset(s, new->ip, 0, 0, 1);
4331 }
4332 else
4333 cache_ipmap(new->ip, s);
4334 }
4335 }
4336
4337 // check v6 routing
4338 if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
4339 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4340
4341 // check filters
4342 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4343 {
4344 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4345 new->filter_in = 0;
4346 }
4347
4348 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4349 {
4350 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4351 new->filter_out = 0;
4352 }
4353
4354 if (new->filter_in != session[s].filter_in)
4355 {
4356 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4357 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4358 }
4359
4360 if (new->filter_out != session[s].filter_out)
4361 {
4362 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4363 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4364 }
4365
4366 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4367 // for walking the sessions to forward byte counts to the master.
4368 config->cluster_highest_sessionid = s;
4369
4370 // TEMP: old session struct used a uint32_t to define the throttle
4371 // speed for both up/down, new uses a uint16_t for each. Deal with
4372 // sessions from an old master for migration.
4373 if (new->throttle_out == 0 && new->tbf_out)
4374 new->throttle_out = new->throttle_in;
4375
4376 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4377
4378 // Do fixups into address pool.
4379 if (new->ip_pool_index != -1)
4380 fix_address_pool(s);
4381
4382 return 1;
4383 }
4384
4385 static void initplugins()
4386 {
4387 int i;
4388
4389 loaded_plugins = ll_init();
4390 // Initialize the plugins to nothing
4391 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4392 plugins[i] = ll_init();
4393 }
4394
4395 static void *open_plugin(char *plugin_name, int load)
4396 {
4397 char path[256] = "";
4398
4399 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4400 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4401 return dlopen(path, RTLD_NOW);
4402 }
4403
4404 // plugin callback to get a config value
4405 static void *getconfig(char *key, enum config_typet type)
4406 {
4407 int i;
4408
4409 for (i = 0; config_values[i].key; i++)
4410 {
4411 if (!strcmp(config_values[i].key, key))
4412 {
4413 if (config_values[i].type == type)
4414 return ((void *) config) + config_values[i].offset;
4415
4416 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4417 key, type, config_values[i].type);
4418
4419 return 0;
4420 }
4421 }
4422
4423 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4424 return 0;
4425 }
4426
4427 static int add_plugin(char *plugin_name)
4428 {
4429 static struct pluginfuncs funcs = {
4430 _log,
4431 _log_hex,
4432 fmtaddr,
4433 sessionbyuser,
4434 sessiontbysessionidt,
4435 sessionidtbysessiont,
4436 radiusnew,
4437 radiussend,
4438 getconfig,
4439 sessionshutdown,
4440 sessionkill,
4441 throttle_session,
4442 cluster_send_session,
4443 };
4444
4445 void *p = open_plugin(plugin_name, 1);
4446 int (*initfunc)(struct pluginfuncs *);
4447 int i;
4448
4449 if (!p)
4450 {
4451 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4452 return -1;
4453 }
4454
4455 if (ll_contains(loaded_plugins, p))
4456 {
4457 dlclose(p);
4458 return 0; // already loaded
4459 }
4460
4461 {
4462 int *v = dlsym(p, "plugin_api_version");
4463 if (!v || *v != PLUGIN_API_VERSION)
4464 {
4465 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4466 dlclose(p);
4467 return -1;
4468 }
4469 }
4470
4471 if ((initfunc = dlsym(p, "plugin_init")))
4472 {
4473 if (!initfunc(&funcs))
4474 {
4475 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4476 dlclose(p);
4477 return -1;
4478 }
4479 }
4480
4481 ll_push(loaded_plugins, p);
4482
4483 for (i = 0; i < max_plugin_functions; i++)
4484 {
4485 void *x;
4486 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4487 {
4488 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4489 ll_push(plugins[i], x);
4490 }
4491 }
4492
4493 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4494 return 1;
4495 }
4496
4497 static void run_plugin_done(void *plugin)
4498 {
4499 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4500
4501 if (donefunc)
4502 donefunc();
4503 }
4504
4505 static int remove_plugin(char *plugin_name)
4506 {
4507 void *p = open_plugin(plugin_name, 0);
4508 int loaded = 0;
4509
4510 if (!p)
4511 return -1;
4512
4513 if (ll_contains(loaded_plugins, p))
4514 {
4515 int i;
4516 for (i = 0; i < max_plugin_functions; i++)
4517 {
4518 void *x;
4519 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4520 ll_delete(plugins[i], x);
4521 }
4522
4523 ll_delete(loaded_plugins, p);
4524 run_plugin_done(p);
4525 loaded = 1;
4526 }
4527
4528 dlclose(p);
4529 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4530 return loaded;
4531 }
4532
4533 int run_plugins(int plugin_type, void *data)
4534 {
4535 int (*func)(void *data);
4536
4537 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4538 return PLUGIN_RET_ERROR;
4539
4540 ll_reset(plugins[plugin_type]);
4541 while ((func = ll_next(plugins[plugin_type])))
4542 {
4543 int r = func(data);
4544
4545 if (r != PLUGIN_RET_OK)
4546 return r; // stop here
4547 }
4548
4549 return PLUGIN_RET_OK;
4550 }
4551
4552 static void plugins_done()
4553 {
4554 void *p;
4555
4556 ll_reset(loaded_plugins);
4557 while ((p = ll_next(loaded_plugins)))
4558 run_plugin_done(p);
4559 }
4560
4561 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4562 {
4563 struct nsctl request;
4564 struct nsctl response;
4565 int type = unpack_control(&request, buf, len);
4566 int r;
4567 void *p;
4568
4569 if (log_stream && config->debug >= 4)
4570 {
4571 if (type < 0)
4572 {
4573 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4574 fmtaddr(addr->sin_addr.s_addr, 0), type);
4575 }
4576 else
4577 {
4578 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4579 dump_control(&request, log_stream);
4580 }
4581 }
4582
4583 switch (type)
4584 {
4585 case NSCTL_REQ_LOAD:
4586 if (request.argc != 1)
4587 {
4588 response.type = NSCTL_RES_ERR;
4589 response.argc = 1;
4590 response.argv[0] = "name of plugin required";
4591 }
4592 else if ((r = add_plugin(request.argv[0])) < 1)
4593 {
4594 response.type = NSCTL_RES_ERR;
4595 response.argc = 1;
4596 response.argv[0] = !r
4597 ? "plugin already loaded"
4598 : "error loading plugin";
4599 }
4600 else
4601 {
4602 response.type = NSCTL_RES_OK;
4603 response.argc = 0;
4604 }
4605
4606 break;
4607
4608 case NSCTL_REQ_UNLOAD:
4609 if (request.argc != 1)
4610 {
4611 response.type = NSCTL_RES_ERR;
4612 response.argc = 1;
4613 response.argv[0] = "name of plugin required";
4614 }
4615 else if ((r = remove_plugin(request.argv[0])) < 1)
4616 {
4617 response.type = NSCTL_RES_ERR;
4618 response.argc = 1;
4619 response.argv[0] = !r
4620 ? "plugin not loaded"
4621 : "plugin not found";
4622 }
4623 else
4624 {
4625 response.type = NSCTL_RES_OK;
4626 response.argc = 0;
4627 }
4628
4629 break;
4630
4631 case NSCTL_REQ_HELP:
4632 response.type = NSCTL_RES_OK;
4633 response.argc = 0;
4634
4635 ll_reset(loaded_plugins);
4636 while ((p = ll_next(loaded_plugins)))
4637 {
4638 char **help = dlsym(p, "plugin_control_help");
4639 while (response.argc < 0xff && help && *help)
4640 response.argv[response.argc++] = *help++;
4641 }
4642
4643 break;
4644
4645 case NSCTL_REQ_CONTROL:
4646 {
4647 struct param_control param = {
4648 config->cluster_iam_master,
4649 request.argc,
4650 request.argv,
4651 0,
4652 NULL,
4653 };
4654
4655 int r = run_plugins(PLUGIN_CONTROL, &param);
4656
4657 if (r == PLUGIN_RET_ERROR)
4658 {
4659 response.type = NSCTL_RES_ERR;
4660 response.argc = 1;
4661 response.argv[0] = param.additional
4662 ? param.additional
4663 : "error returned by plugin";
4664 }
4665 else if (r == PLUGIN_RET_NOTMASTER)
4666 {
4667 static char msg[] = "must be run on master: 000.000.000.000";
4668
4669 response.type = NSCTL_RES_ERR;
4670 response.argc = 1;
4671 if (config->cluster_master_address)
4672 {
4673 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4674 response.argv[0] = msg;
4675 }
4676 else
4677 {
4678 response.argv[0] = "must be run on master: none elected";
4679 }
4680 }
4681 else if (!(param.response & NSCTL_RESPONSE))
4682 {
4683 response.type = NSCTL_RES_ERR;
4684 response.argc = 1;
4685 response.argv[0] = param.response
4686 ? "unrecognised response value from plugin"
4687 : "unhandled action";
4688 }
4689 else
4690 {
4691 response.type = param.response;
4692 response.argc = 0;
4693 if (param.additional)
4694 {
4695 response.argc = 1;
4696 response.argv[0] = param.additional;
4697 }
4698 }
4699 }
4700
4701 break;
4702
4703 default:
4704 response.type = NSCTL_RES_ERR;
4705 response.argc = 1;
4706 response.argv[0] = "error unpacking control packet";
4707 }
4708
4709 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4710 if (!buf)
4711 {
4712 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4713 return;
4714 }
4715
4716 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4717 if (r > 0)
4718 {
4719 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4720 if (log_stream && config->debug >= 4)
4721 {
4722 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4723 dump_control(&response, log_stream);
4724 }
4725 }
4726 else
4727 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4728 fmtaddr(addr->sin_addr.s_addr, 0), r);
4729
4730 free(buf);
4731 }
4732
4733 static tunnelidt new_tunnel()
4734 {
4735 tunnelidt i;
4736 for (i = 1; i < MAXTUNNEL; i++)
4737 {
4738 if (tunnel[i].state == TUNNELFREE)
4739 {
4740 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4741 if (i > config->cluster_highest_tunnelid)
4742 config->cluster_highest_tunnelid = i;
4743 return i;
4744 }
4745 }
4746 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4747 return 0;
4748 }
4749
4750 //
4751 // We're becoming the master. Do any required setup..
4752 //
4753 // This is principally telling all the plugins that we're
4754 // now a master, and telling them about all the sessions
4755 // that are active too..
4756 //
4757 void become_master(void)
4758 {
4759 int s, i;
4760 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4761
4762 // running a bunch of iptables commands is slow and can cause
4763 // the master to drop tunnels on takeover--kludge around the
4764 // problem by forking for the moment (note: race)
4765 if (!fork_and_close())
4766 {
4767 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4768 {
4769 if (!session[s].opened) // Not an in-use session.
4770 continue;
4771
4772 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4773 }
4774 exit(0);
4775 }
4776
4777 // add radius fds
4778 for (i = 0; i < config->num_radfds; i++)
4779 {
4780 FD_SET(radfds[i], &readset);
4781 if (radfds[i] > readset_n)
4782 readset_n = radfds[i];
4783 }
4784 }
4785
4786 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4787 {
4788 int s, i;
4789 int count = 0;
4790 int buckets[64];
4791
4792 if (CLI_HELP_REQUESTED)
4793 return CLI_HELP_NO_ARGS;
4794
4795 time(&time_now);
4796 for (i = 0; i < 64;++i) buckets[i] = 0;
4797
4798 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4799 {
4800 int idle;
4801 if (!session[s].opened)
4802 continue;
4803
4804 idle = time_now - session[s].last_packet;
4805 idle /= 5 ; // In multiples of 5 seconds.
4806 if (idle < 0)
4807 idle = 0;
4808 if (idle > 63)
4809 idle = 63;
4810
4811 ++count;
4812 ++buckets[idle];
4813 }
4814
4815 for (i = 0; i < 63; ++i)
4816 {
4817 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4818 }
4819 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4820 cli_print(cli, "%d total sessions open.", count);
4821 return CLI_OK;
4822 }
4823
4824 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4825 {
4826 int s, i;
4827 int count = 0;
4828 int buckets[64];
4829
4830 if (CLI_HELP_REQUESTED)
4831 return CLI_HELP_NO_ARGS;
4832
4833 time(&time_now);
4834 for (i = 0; i < 64;++i) buckets[i] = 0;
4835
4836 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4837 {
4838 int open = 0, d;
4839 if (!session[s].opened)
4840 continue;
4841
4842 d = time_now - session[s].opened;
4843 if (d < 0)
4844 d = 0;
4845 while (d > 1 && open < 32)
4846 {
4847 ++open;
4848 d >>= 1; // half.
4849 }
4850 ++count;
4851 ++buckets[open];
4852 }
4853
4854 s = 1;
4855 for (i = 0; i < 30; ++i)
4856 {
4857 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4858 s <<= 1;
4859 }
4860 cli_print(cli, "%d total sessions open.", count);
4861 return CLI_OK;
4862 }
4863
4864 /* Unhide an avp.
4865 *
4866 * This unencodes the AVP using the L2TP secret and the previously
4867 * stored random vector. It overwrites the hidden data with the
4868 * unhidden AVP subformat.
4869 */
4870 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
4871 {
4872 MD5_CTX ctx;
4873 uint8_t digest[16];
4874 uint8_t *last;
4875 size_t d = 0;
4876
4877 // Compute initial pad
4878 MD5Init(&ctx);
4879 MD5Update(&ctx, (uint8_t) (type >> 8) & 0xff, 1);
4880 MD5Update(&ctx, (uint8_t) type & 0xff, 1);
4881 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4882 MD5Update(&ctx, vector, vec_len);
4883 MD5Final(digest, &ctx);
4884
4885 // pointer to last decoded 16 octets
4886 last = value;
4887
4888 while (len > 0)
4889 {
4890 // calculate a new pad based on the last decoded block
4891 if (d >= sizeof(digest))
4892 {
4893 MD5Init(&ctx);
4894 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4895 MD5Update(&ctx, last, sizeof(digest));
4896 MD5Final(digest, &ctx);
4897
4898 d = 0;
4899 last = value;
4900 }
4901
4902 *value++ ^= digest[d++];
4903 len--;
4904 }
4905 }
4906
4907 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
4908 {
4909 switch (p->op)
4910 {
4911 case FILTER_PORT_OP_EQ: return port == p->port;
4912 case FILTER_PORT_OP_NEQ: return port != p->port;
4913 case FILTER_PORT_OP_GT: return port > p->port;
4914 case FILTER_PORT_OP_LT: return port < p->port;
4915 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
4916 }
4917
4918 return 0;
4919 }
4920
4921 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
4922 {
4923 switch (op)
4924 {
4925 case FILTER_FLAG_OP_ANY:
4926 return (flags & sflags) || (~flags & cflags);
4927
4928 case FILTER_FLAG_OP_ALL:
4929 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
4930
4931 case FILTER_FLAG_OP_EST:
4932 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
4933 }
4934
4935 return 0;
4936 }
4937
4938 int ip_filter(uint8_t *buf, int len, uint8_t filter)
4939 {
4940 uint16_t frag_offset;
4941 uint8_t proto;
4942 in_addr_t src_ip;
4943 in_addr_t dst_ip;
4944 uint16_t src_port = 0;
4945 uint16_t dst_port = 0;
4946 uint8_t flags = 0;
4947 ip_filter_rulet *rule;
4948
4949 if (len < 20) // up to end of destination address
4950 return 0;
4951
4952 if ((*buf >> 4) != 4) // IPv4
4953 return 0;
4954
4955 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
4956 proto = buf[9];
4957 src_ip = *(in_addr_t *) (buf + 12);
4958 dst_ip = *(in_addr_t *) (buf + 16);
4959
4960 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
4961 {
4962 int l = (buf[0] & 0xf) * 4; // length of IP header
4963 if (len < l + 4) // ports
4964 return 0;
4965
4966 src_port = ntohs(*(uint16_t *) (buf + l));
4967 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
4968 if (proto == IPPROTO_TCP)
4969 {
4970 if (len < l + 14) // flags
4971 return 0;
4972
4973 flags = buf[l + 13] & 0x3f;
4974 }
4975 }
4976
4977 for (rule = ip_filters[filter].rules; rule->action; rule++)
4978 {
4979 if (rule->proto != IPPROTO_IP && proto != rule->proto)
4980 continue;
4981
4982 if (rule->src_wild != INADDR_BROADCAST &&
4983 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
4984 continue;
4985
4986 if (rule->dst_wild != INADDR_BROADCAST &&
4987 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
4988 continue;
4989
4990 if (frag_offset)
4991 {
4992 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
4993 continue;
4994 }
4995 else
4996 {
4997 if (rule->frag)
4998 continue;
4999
5000 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
5001 {
5002 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5003 continue;
5004
5005 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5006 continue;
5007
5008 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5009 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5010 continue;
5011 }
5012 }
5013
5014 // matched
5015 rule->counter++;
5016 return rule->action == FILTER_ACTION_PERMIT;
5017 }
5018
5019 // default deny
5020 return 0;
5021 }