177af10aaa06e7d5821c96704e6cddf61c920c75
[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 1.102 2005/05/12 04:08:45 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 controlt *c;
2309
2310 if (sessionfree)
2311 {
2312 uint16_t r;
2313
2314 s = sessionfree;
2315 sessionfree = session[s].next;
2316 memset(&session[s], 0, sizeof(session[s]));
2317
2318 if (s > config->cluster_highest_sessionid)
2319 config->cluster_highest_sessionid = s;
2320
2321 // make a RADIUS session
2322 if ((r = radiusnew(s)))
2323 {
2324 c = controlnew(11); // sending ICRP
2325 session[s].opened = time_now;
2326 session[s].tunnel = t;
2327 session[s].far = asession;
2328 session[s].last_packet = time_now;
2329 LOG(3, s, t, "New session (%d/%d)\n", tunnel[t].far, session[s].far);
2330 control16(c, 14, s, 1); // assigned session
2331 controladd(c, t, asession); // send the reply
2332
2333 strncpy(radius[r].calling, calling, sizeof(radius[r].calling) - 1);
2334 strncpy(session[s].called, called, sizeof(session[s].called) - 1);
2335 strncpy(session[s].calling, calling, sizeof(session[s].calling) - 1);
2336 STAT(session_created);
2337 break;
2338 }
2339
2340
2341 LOG(1, s, t, "No free RADIUS sessions for ICRQ\n");
2342 sessionclear(s);
2343 }
2344 else
2345 {
2346 STAT(session_overflow);
2347 LOG(1, 0, t, "No free sessions\n");
2348 }
2349
2350 c = controlnew(14); // CDN
2351 control16(c, 1, 4, 1); // temporary lack of resources
2352 controladd(c, session[s].tunnel, asession); // send the message
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 (authtype && !(config->radius_authtypes & authtype))
2365 sendlcp(t, s, config->radius_authprefer);
2366 break;
2367 case 14: // CDN
2368 controlnull(t); // ack
2369 sessionshutdown(s, "Closed (Received CDN).", 0, 0);
2370 break;
2371 case 0xFFFF:
2372 LOG(1, s, t, "Missing message type\n");
2373 break;
2374 default:
2375 STAT(tunnel_rx_errors);
2376 if (mandatory)
2377 tunnelshutdown(t, "Unknown message type", 2, 6, "unknown message type");
2378 else
2379 LOG(1, s, t, "Unknown message type %d\n", message);
2380 break;
2381 }
2382 if (chapresponse) free(chapresponse);
2383 cluster_send_tunnel(t);
2384 }
2385 else
2386 {
2387 LOG(4, s, t, " Got a ZLB ack\n");
2388 }
2389 }
2390 else
2391 { // data
2392 uint16_t prot;
2393
2394 LOG_HEX(5, "Receive Tunnel Data", p, l);
2395 if (l > 2 && p[0] == 0xFF && p[1] == 0x03)
2396 { // HDLC address header, discard
2397 p += 2;
2398 l -= 2;
2399 }
2400 if (l < 2)
2401 {
2402 LOG(1, s, t, "Short ppp length %d\n", l);
2403 STAT(tunnel_rx_errors);
2404 return;
2405 }
2406 if (*p & 1)
2407 {
2408 prot = *p++;
2409 l--;
2410 }
2411 else
2412 {
2413 prot = ntohs(*(uint16_t *) p);
2414 p += 2;
2415 l -= 2;
2416 }
2417
2418 if (s && !session[s].opened) // Is something wrong??
2419 {
2420 if (!config->cluster_iam_master)
2421 {
2422 // Pass it off to the master to deal with..
2423 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2424 return;
2425 }
2426
2427
2428 LOG(1, s, t, "UDP packet contains session which is not opened. Dropping packet.\n");
2429 STAT(tunnel_rx_errors);
2430 return;
2431 }
2432
2433 if (prot == PPPPAP)
2434 {
2435 session[s].last_packet = time_now;
2436 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2437 processpap(t, s, p, l);
2438 }
2439 else if (prot == PPPCHAP)
2440 {
2441 session[s].last_packet = time_now;
2442 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2443 processchap(t, s, p, l);
2444 }
2445 else if (prot == PPPLCP)
2446 {
2447 session[s].last_packet = time_now;
2448 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2449 processlcp(t, s, p, l);
2450 }
2451 else if (prot == PPPIPCP)
2452 {
2453 session[s].last_packet = time_now;
2454 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2455 processipcp(t, s, p, l);
2456 }
2457 else if (prot == PPPIPV6CP)
2458 {
2459 if (config->ipv6_prefix.s6_addr[0] > 0)
2460 {
2461 session[s].last_packet = time_now;
2462 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2463 processipv6cp(t, s, p, l);
2464 }
2465 else
2466 {
2467 LOG(1, s, t, "IPv6 not configured; ignoring IPv6CP\n");
2468 }
2469 }
2470 else if (prot == PPPCCP)
2471 {
2472 session[s].last_packet = time_now;
2473 if (!config->cluster_iam_master) { master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port); return; }
2474 processccp(t, s, p, l);
2475 }
2476 else if (prot == PPPIP)
2477 {
2478 if (session[s].die)
2479 {
2480 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2481 return; // closing session, PPP not processed
2482 }
2483
2484 session[s].last_packet = time_now;
2485 if (session[s].walled_garden && !config->cluster_iam_master)
2486 {
2487 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2488 return;
2489 }
2490
2491 processipin(t, s, p, l);
2492 }
2493 else if (prot == PPPIPV6)
2494 {
2495 if (!config->ipv6_prefix.s6_addr[0] > 0)
2496 {
2497 LOG(1, s, t, "IPv6 not configured; yet received IPv6 packet. Ignoring.\n");
2498 return;
2499 }
2500 if (session[s].die)
2501 {
2502 LOG(4, s, t, "Session %d is closing. Don't process PPP packets\n", s);
2503 return; // closing session, PPP not processed
2504 }
2505
2506 session[s].last_packet = time_now;
2507 if (session[s].walled_garden && !config->cluster_iam_master)
2508 {
2509 master_forward_packet(buf, len, addr->sin_addr.s_addr, addr->sin_port);
2510 return;
2511 }
2512
2513 processipv6in(t, s, p, l);
2514 }
2515 else
2516 {
2517 STAT(tunnel_rx_errors);
2518 LOG(1, s, t, "Unknown PPP protocol %04X\n", prot);
2519 }
2520 }
2521 }
2522
2523 // read and process packet on tun
2524 static void processtun(uint8_t * buf, int len)
2525 {
2526 LOG_HEX(5, "Receive TUN Data", buf, len);
2527 STAT(tun_rx_packets);
2528 INC_STAT(tun_rx_bytes, len);
2529
2530 CSTAT(processtun);
2531
2532 eth_rx_pkt++;
2533 eth_rx += len;
2534 if (len < 22)
2535 {
2536 LOG(1, 0, 0, "Short tun packet %d bytes\n", len);
2537 STAT(tun_rx_errors);
2538 return;
2539 }
2540
2541 if (*(uint16_t *) (buf + 2) == htons(PKTIP)) // IPv4
2542 processipout(buf, len);
2543 else if (*(uint16_t *) (buf + 2) == htons(PKTIPV6) // IPV6
2544 && config->ipv6_prefix.s6_addr[0] > 0)
2545 processipv6out(buf, len);
2546
2547 // Else discard.
2548 }
2549
2550 //
2551 // Maximum number of actions to complete.
2552 // This is to avoid sending out too many packets
2553 // at once.
2554 #define MAX_ACTIONS 500
2555
2556 static int regular_cleanups(void)
2557 {
2558 static sessionidt s = 0; // Next session to check for actions on.
2559 tunnelidt t;
2560 int count=0,i;
2561 uint16_t r;
2562 static clockt next_acct = 0;
2563 static clockt next_shut_acct = 0;
2564 int a;
2565
2566 LOG(3, 0, 0, "Begin regular cleanup\n");
2567
2568 for (r = 1; r < MAXRADIUS; r++)
2569 {
2570 if (!radius[r].state)
2571 continue;
2572 if (radius[r].retry)
2573 {
2574 if (radius[r].retry <= TIME)
2575 radiusretry(r);
2576 } else
2577 radius[r].retry = backoff(radius[r].try+1); // Is this really needed? --mo
2578 }
2579 for (t = 1; t <= config->cluster_highest_tunnelid; t++)
2580 {
2581 // check for expired tunnels
2582 if (tunnel[t].die && tunnel[t].die <= TIME)
2583 {
2584 STAT(tunnel_timeout);
2585 tunnelkill(t, "Expired");
2586 continue;
2587 }
2588 // check for message resend
2589 if (tunnel[t].retry && tunnel[t].controlc)
2590 {
2591 // resend pending messages as timeout on reply
2592 if (tunnel[t].retry <= TIME)
2593 {
2594 controlt *c = tunnel[t].controls;
2595 uint8_t w = tunnel[t].window;
2596 tunnel[t].try++; // another try
2597 if (tunnel[t].try > 5)
2598 tunnelkill(t, "Timeout on control message"); // game over
2599 else
2600 while (c && w--)
2601 {
2602 tunnelsend(c->buf, c->length, t);
2603 c = c->next;
2604 }
2605 }
2606 }
2607 // Send hello
2608 if (tunnel[t].state == TUNNELOPEN && tunnel[t].lastrec < TIME + 600)
2609 {
2610 controlt *c = controlnew(6); // sending HELLO
2611 controladd(c, t, 0); // send the message
2612 LOG(3, 0, t, "Sending HELLO message\n");
2613 }
2614
2615 // Check for tunnel changes requested from the CLI
2616 if ((a = cli_tunnel_actions[t].action))
2617 {
2618 cli_tunnel_actions[t].action = 0;
2619 if (a & CLI_TUN_KILL)
2620 {
2621 LOG(2, 0, t, "Dropping tunnel by CLI\n");
2622 tunnelshutdown(t, "Requested by administrator", 1, 0, 0);
2623 }
2624 }
2625
2626 }
2627
2628 count = 0;
2629 for (i = 1; i <= config->cluster_highest_sessionid; i++)
2630 {
2631 s++;
2632 if (s > config->cluster_highest_sessionid)
2633 s = 1;
2634
2635 if (!session[s].opened) // Session isn't in use
2636 continue;
2637
2638 // check for expired sessions
2639 if (session[s].die)
2640 {
2641 if (session[s].die <= TIME)
2642 {
2643 sessionkill(s, "Expired");
2644 if (++count >= MAX_ACTIONS) break;
2645 }
2646 continue;
2647 }
2648
2649 if (session[s].ip && !(session[s].flags & SF_IPCP_ACKED))
2650 {
2651 // IPCP has not completed yet. Resend
2652 LOG(3, s, session[s].tunnel, "No ACK for initial IPCP ConfigReq... resending\n");
2653 sendipcp(session[s].tunnel, s);
2654 }
2655
2656 // Drop sessions who have not responded within IDLE_TIMEOUT seconds
2657 if (session[s].last_packet && (time_now - session[s].last_packet >= IDLE_TIMEOUT))
2658 {
2659 sessionshutdown(s, "No response to LCP ECHO requests.", 3, 0);
2660 STAT(session_timeout);
2661 if (++count >= MAX_ACTIONS) break;
2662 continue;
2663 }
2664
2665 // No data in ECHO_TIMEOUT seconds, send LCP ECHO
2666 if (session[s].user[0] && (time_now - session[s].last_packet >= ECHO_TIMEOUT))
2667 {
2668 uint8_t b[MAXCONTROL] = {0};
2669
2670 uint8_t *q = makeppp(b, sizeof(b), 0, 0, session[s].tunnel, s, PPPLCP);
2671 if (!q) continue;
2672
2673 *q = EchoReq;
2674 *(uint8_t *)(q + 1) = (time_now % 255); // ID
2675 *(uint16_t *)(q + 2) = htons(8); // Length
2676 *(uint32_t *)(q + 4) = 0; // Magic Number (not supported)
2677
2678 LOG(4, s, session[s].tunnel, "No data in %d seconds, sending LCP ECHO\n",
2679 (int)(time_now - session[s].last_packet));
2680 tunnelsend(b, 24, session[s].tunnel); // send it
2681 if (++count >= MAX_ACTIONS) break;
2682 }
2683
2684 // Check for actions requested from the CLI
2685 if ((a = cli_session_actions[s].action))
2686 {
2687 int send = 0;
2688
2689 cli_session_actions[s].action = 0;
2690 if (a & CLI_SESS_KILL)
2691 {
2692 LOG(2, s, session[s].tunnel, "Dropping session by CLI\n");
2693 sessionshutdown(s, "Requested by administrator.", 3, 0);
2694 a = 0; // dead, no need to check for other actions
2695 }
2696
2697 if (a & CLI_SESS_NOSNOOP)
2698 {
2699 LOG(2, s, session[s].tunnel, "Unsnooping session by CLI\n");
2700 session[s].snoop_ip = 0;
2701 session[s].snoop_port = 0;
2702 send++;
2703 }
2704 else if (a & CLI_SESS_SNOOP)
2705 {
2706 LOG(2, s, session[s].tunnel, "Snooping session by CLI (to %s:%d)\n",
2707 fmtaddr(cli_session_actions[s].snoop_ip, 0),
2708 cli_session_actions[s].snoop_port);
2709
2710 session[s].snoop_ip = cli_session_actions[s].snoop_ip;
2711 session[s].snoop_port = cli_session_actions[s].snoop_port;
2712 send++;
2713 }
2714
2715 if (a & CLI_SESS_NOTHROTTLE)
2716 {
2717 LOG(2, s, session[s].tunnel, "Un-throttling session by CLI\n");
2718 throttle_session(s, 0, 0);
2719 send++;
2720 }
2721 else if (a & CLI_SESS_THROTTLE)
2722 {
2723 LOG(2, s, session[s].tunnel, "Throttling session by CLI (to %dkb/s up and %dkb/s down)\n",
2724 cli_session_actions[s].throttle_in,
2725 cli_session_actions[s].throttle_out);
2726
2727 throttle_session(s, cli_session_actions[s].throttle_in, cli_session_actions[s].throttle_out);
2728 send++;
2729 }
2730
2731 if (a & CLI_SESS_NOFILTER)
2732 {
2733 LOG(2, s, session[s].tunnel, "Un-filtering session by CLI\n");
2734 filter_session(s, 0, 0);
2735 send++;
2736 }
2737 else if (a & CLI_SESS_FILTER)
2738 {
2739 LOG(2, s, session[s].tunnel, "Filtering session by CLI (in=%d, out=%d)\n",
2740 cli_session_actions[s].filter_in,
2741 cli_session_actions[s].filter_out);
2742
2743 filter_session(s, cli_session_actions[s].filter_in, cli_session_actions[s].filter_out);
2744 send++;
2745 }
2746
2747 if (send)
2748 cluster_send_session(s);
2749
2750 if (++count >= MAX_ACTIONS) break;
2751 }
2752
2753 // RADIUS interim accounting
2754 if (config->radius_accounting && config->radius_interim > 0
2755 && session[s].ip && !session[s].walled_garden
2756 && !sess_local[s].radius // RADIUS already in progress
2757 && time_now - sess_local[s].last_interim >= config->radius_interim)
2758 {
2759 if (!(r = radiusnew(s)))
2760 {
2761 LOG(1, s, session[s].tunnel, "No free RADIUS sessions for Interim message\n");
2762 STAT(radius_overflow);
2763 continue;
2764 }
2765
2766 LOG(3, s, session[s].tunnel, "Sending RADIUS Interim for %s (%u)\n",
2767 session[s].user, session[s].unique_id);
2768
2769 radiussend(r, RADIUSINTERIM);
2770 sess_local[s].last_interim = time_now;
2771
2772 if (++count >= MAX_ACTIONS)
2773 break;
2774 }
2775 }
2776
2777 if (*config->accounting_dir)
2778 {
2779 if (next_acct <= TIME)
2780 {
2781 // Dump accounting data
2782 next_acct = TIME + ACCT_TIME;
2783 next_shut_acct = TIME + ACCT_SHUT_TIME;
2784 dump_acct_info(1);
2785 }
2786 else if (next_shut_acct <= TIME)
2787 {
2788 // Dump accounting data for shutdown sessions
2789 next_shut_acct = TIME + ACCT_SHUT_TIME;
2790 if (shut_acct_n)
2791 dump_acct_info(0);
2792 }
2793 }
2794
2795 if (count >= MAX_ACTIONS)
2796 return 1; // Didn't finish!
2797
2798 LOG(3, 0, 0, "End regular cleanup (%d actions), next in %d seconds\n", count, config->cleanup_interval);
2799 return 0;
2800 }
2801
2802
2803 //
2804 // Are we in the middle of a tunnel update, or radius
2805 // requests??
2806 //
2807 static int still_busy(void)
2808 {
2809 int i;
2810 static clockt last_talked = 0;
2811 static clockt start_busy_wait = 0;
2812 if (start_busy_wait == 0)
2813 start_busy_wait = TIME;
2814
2815 for (i = config->cluster_highest_tunnelid ; i > 0 ; --i)
2816 {
2817 if (!tunnel[i].controlc)
2818 continue;
2819
2820 if (last_talked != TIME)
2821 {
2822 LOG(2, 0, 0, "Tunnel %d still has un-acked control messages.\n", i);
2823 last_talked = TIME;
2824 }
2825 return 1;
2826 }
2827
2828 // We stop waiting for radius after BUSY_WAIT_TIME 1/10th seconds
2829 if (abs(TIME - start_busy_wait) > BUSY_WAIT_TIME)
2830 {
2831 LOG(1, 0, 0, "Giving up waiting for RADIUS to be empty. Shutting down anyway.\n");
2832 return 0;
2833 }
2834
2835 for (i = 1; i < MAXRADIUS; i++)
2836 {
2837 if (radius[i].state == RADIUSNULL)
2838 continue;
2839 if (radius[i].state == RADIUSWAIT)
2840 continue;
2841
2842 if (last_talked != TIME)
2843 {
2844 LOG(2, 0, 0, "Radius session %d is still busy (sid %d)\n", i, radius[i].session);
2845 last_talked = TIME;
2846 }
2847 return 1;
2848 }
2849
2850 return 0;
2851 }
2852
2853 static fd_set readset;
2854 static int readset_n = 0;
2855
2856 // main loop - gets packets on tun or udp and processes them
2857 static void mainloop(void)
2858 {
2859 int i;
2860 uint8_t buf[65536];
2861 struct timeval to;
2862 clockt next_cluster_ping = 0; // send initial ping immediately
2863 time_t next_clean = time_now + config->cleanup_interval;
2864
2865 LOG(4, 0, 0, "Beginning of main loop. udpfd=%d, tunfd=%d, cluster_sockfd=%d, controlfd=%d\n",
2866 udpfd, tunfd, cluster_sockfd, controlfd);
2867
2868 FD_ZERO(&readset);
2869 FD_SET(udpfd, &readset);
2870 FD_SET(tunfd, &readset);
2871 FD_SET(controlfd, &readset);
2872 FD_SET(clifd, &readset);
2873 if (cluster_sockfd) FD_SET(cluster_sockfd, &readset);
2874 readset_n = udpfd;
2875 if (tunfd > readset_n) readset_n = tunfd;
2876 if (controlfd > readset_n) readset_n = controlfd;
2877 if (clifd > readset_n) readset_n = clifd;
2878 if (cluster_sockfd > readset_n) readset_n = cluster_sockfd;
2879
2880 while (!main_quit || still_busy())
2881 {
2882 fd_set r;
2883 int n = readset_n;
2884 #ifdef BGP
2885 fd_set w;
2886 int bgp_set[BGP_NUM_PEERS];
2887 #endif /* BGP */
2888
2889 if (config->reload_config)
2890 {
2891 // Update the config state based on config settings
2892 update_config();
2893 }
2894
2895 memcpy(&r, &readset, sizeof(fd_set));
2896 to.tv_sec = 0;
2897 to.tv_usec = 100000; // 1/10th of a second.
2898
2899 #ifdef BGP
2900 FD_ZERO(&w);
2901 for (i = 0; i < BGP_NUM_PEERS; i++)
2902 {
2903 bgp_set[i] = bgp_select_state(&bgp_peers[i]);
2904 if (bgp_set[i] & 1)
2905 {
2906 FD_SET(bgp_peers[i].sock, &r);
2907 if (bgp_peers[i].sock > n)
2908 n = bgp_peers[i].sock;
2909 }
2910
2911 if (bgp_set[i] & 2)
2912 {
2913 FD_SET(bgp_peers[i].sock, &w);
2914 if (bgp_peers[i].sock > n)
2915 n = bgp_peers[i].sock;
2916 }
2917 }
2918
2919 n = select(n + 1, &r, &w, 0, &to);
2920 #else /* BGP */
2921 n = select(n + 1, &r, 0, 0, &to);
2922 #endif /* BGP */
2923
2924 STAT(select_called);
2925
2926 TIME = now();
2927 if (n < 0)
2928 {
2929 if (errno == EINTR ||
2930 errno == ECHILD) // EINTR was clobbered by sigchild_handler()
2931 continue;
2932
2933 LOG(0, 0, 0, "Error returned from select(): %s\n", strerror(errno));
2934 main_quit++;
2935 break;
2936 }
2937 else if (n)
2938 {
2939 struct sockaddr_in addr;
2940 int alen, c, s;
2941 int udp_pkts = 0;
2942 int tun_pkts = 0;
2943 int cluster_pkts = 0;
2944
2945 // nsctl commands
2946 if (FD_ISSET(controlfd, &r))
2947 {
2948 alen = sizeof(addr);
2949 processcontrol(buf, recvfrom(controlfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen), &addr, alen);
2950 n--;
2951 }
2952
2953 // RADIUS responses
2954 if (config->cluster_iam_master)
2955 {
2956 for (i = 0; i < config->num_radfds; i++)
2957 {
2958 if (FD_ISSET(radfds[i], &r))
2959 {
2960 processrad(buf, recv(radfds[i], buf, sizeof(buf), 0), i);
2961 n--;
2962 }
2963 }
2964 }
2965
2966 // CLI connections
2967 if (FD_ISSET(clifd, &r))
2968 {
2969 int cli;
2970
2971 alen = sizeof(addr);
2972 if ((cli = accept(clifd, (struct sockaddr *)&addr, &alen)) >= 0)
2973 {
2974 cli_do(cli);
2975 close(cli);
2976 }
2977 else
2978 LOG(0, 0, 0, "accept error: %s\n", strerror(errno));
2979
2980 n--;
2981 }
2982
2983 #ifdef BGP
2984 for (i = 0; i < BGP_NUM_PEERS; i++)
2985 {
2986 int isr = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &r) : 0;
2987 int isw = bgp_set[i] ? FD_ISSET(bgp_peers[i].sock, &w) : 0;
2988 bgp_process(&bgp_peers[i], isr, isw);
2989 if (isr) n--;
2990 if (isw) n--;
2991 }
2992 #endif /* BGP */
2993
2994 for (c = 0; n && c < config->multi_read_count; c++)
2995 {
2996 // L2TP
2997 if (FD_ISSET(udpfd, &r))
2998 {
2999 alen = sizeof(addr);
3000 if ((s = recvfrom(udpfd, buf, sizeof(buf), 0, (void *) &addr, &alen)) > 0)
3001 {
3002 processudp(buf, s, &addr);
3003 udp_pkts++;
3004 }
3005 else
3006 {
3007 FD_CLR(udpfd, &r);
3008 n--;
3009 }
3010 }
3011
3012 // incoming IP
3013 if (FD_ISSET(tunfd, &r))
3014 {
3015 if ((s = read(tunfd, buf, sizeof(buf))) > 0)
3016 {
3017 processtun(buf, s);
3018 tun_pkts++;
3019 }
3020 else
3021 {
3022 FD_CLR(tunfd, &r);
3023 n--;
3024 }
3025 }
3026
3027 // cluster
3028 if (FD_ISSET(cluster_sockfd, &r))
3029 {
3030 alen = sizeof(addr);
3031 if ((s = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen)) > 0)
3032 {
3033 processcluster(buf, s, addr.sin_addr.s_addr);
3034 cluster_pkts++;
3035 }
3036 else
3037 {
3038 FD_CLR(cluster_sockfd, &r);
3039 n--;
3040 }
3041 }
3042 }
3043
3044 if (udp_pkts > 1 || tun_pkts > 1 || cluster_pkts > 1)
3045 STAT(multi_read_used);
3046
3047 if (c >= config->multi_read_count)
3048 {
3049 LOG(3, 0, 0, "Reached multi_read_count (%d); processed %d udp, %d tun and %d cluster packets\n",
3050 config->multi_read_count, udp_pkts, tun_pkts, cluster_pkts);
3051
3052 STAT(multi_read_exceeded);
3053 }
3054 }
3055
3056 // Runs on every machine (master and slaves).
3057 if (cluster_sockfd && next_cluster_ping <= TIME)
3058 {
3059 // Check to see which of the cluster is still alive..
3060
3061 cluster_send_ping(basetime); // Only does anything if we're a slave
3062 cluster_check_master(); // ditto.
3063
3064 cluster_heartbeat(); // Only does anything if we're a master.
3065 cluster_check_slaves(); // ditto.
3066
3067 master_update_counts(); // If we're a slave, send our byte counters to our master.
3068
3069 if (config->cluster_iam_master && !config->cluster_iam_uptodate)
3070 next_cluster_ping = TIME + 1; // out-of-date slaves, do fast updates
3071 else
3072 next_cluster_ping = TIME + config->cluster_hb_interval;
3073 }
3074
3075 // Run token bucket filtering queue..
3076 // Only run it every 1/10th of a second.
3077 // Runs on all machines both master and slave.
3078 {
3079 static clockt last_run = 0;
3080 if (last_run != TIME)
3081 {
3082 last_run = TIME;
3083 tbf_run_timer();
3084 }
3085 }
3086
3087 /* Handle timeouts. Make sure that this gets run anyway, even if there was
3088 * something to read, else under load this will never actually run....
3089 *
3090 */
3091 if (config->cluster_iam_master && next_clean <= time_now)
3092 {
3093 if (regular_cleanups())
3094 {
3095 // Did it finish?
3096 next_clean = time_now + 1 ; // Didn't finish. Check quickly.
3097 }
3098 else
3099 {
3100 next_clean = time_now + config->cleanup_interval; // Did. Move to next interval.
3101 }
3102 }
3103 }
3104
3105 // Are we the master and shutting down??
3106 if (config->cluster_iam_master)
3107 cluster_heartbeat(); // Flush any queued changes..
3108
3109 // Ok. Notify everyone we're shutting down. If we're
3110 // the master, this will force an election.
3111 cluster_send_ping(0);
3112
3113 //
3114 // Important!!! We MUST not process any packets past this point!
3115 }
3116
3117 static void stripdomain(char *host)
3118 {
3119 char *p;
3120
3121 if ((p = strchr(host, '.')))
3122 {
3123 char *domain = 0;
3124 char _domain[1024];
3125
3126 // strip off domain
3127 FILE *resolv = fopen("/etc/resolv.conf", "r");
3128 if (resolv)
3129 {
3130 char buf[1024];
3131 char *b;
3132
3133 while (fgets(buf, sizeof(buf), resolv))
3134 {
3135 if (strncmp(buf, "domain", 6) && strncmp(buf, "search", 6))
3136 continue;
3137
3138 if (!isspace(buf[6]))
3139 continue;
3140
3141 b = buf + 7;
3142 while (isspace(*b)) b++;
3143
3144 if (*b)
3145 {
3146 char *d = b;
3147 while (*b && !isspace(*b)) b++;
3148 *b = 0;
3149 if (buf[0] == 'd') // domain is canonical
3150 {
3151 domain = d;
3152 break;
3153 }
3154
3155 // first search line
3156 if (!domain)
3157 {
3158 // hold, may be subsequent domain line
3159 strncpy(_domain, d, sizeof(_domain))[sizeof(_domain)-1] = 0;
3160 domain = _domain;
3161 }
3162 }
3163 }
3164
3165 fclose(resolv);
3166 }
3167
3168 if (domain)
3169 {
3170 int hl = strlen(host);
3171 int dl = strlen(domain);
3172 if (dl < hl && host[hl - dl - 1] == '.' && !strcmp(host + hl - dl, domain))
3173 host[hl -dl - 1] = 0;
3174 }
3175 else
3176 {
3177 *p = 0; // everything after first dot
3178 }
3179 }
3180 }
3181
3182 // Init data structures
3183 static void initdata(int optdebug, char *optconfig)
3184 {
3185 int i;
3186
3187 if (!(config = shared_malloc(sizeof(configt))))
3188 {
3189 fprintf(stderr, "Error doing malloc for configuration: %s\n", strerror(errno));
3190 exit(1);
3191 }
3192
3193 memset(config, 0, sizeof(configt));
3194 time(&config->start_time);
3195 strncpy(config->config_file, optconfig, strlen(optconfig));
3196 config->debug = optdebug;
3197 config->num_tbfs = MAXTBFS;
3198 config->rl_rate = 28; // 28kbps
3199 strcpy(config->random_device, RANDOMDEVICE);
3200
3201 log_stream = stderr;
3202
3203 #ifdef RINGBUFFER
3204 if (!(ringbuffer = shared_malloc(sizeof(struct Tringbuffer))))
3205 {
3206 LOG(0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
3207 exit(1);
3208 }
3209 memset(ringbuffer, 0, sizeof(struct Tringbuffer));
3210 #endif
3211
3212 if (!(_statistics = shared_malloc(sizeof(struct Tstats))))
3213 {
3214 LOG(0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
3215 exit(1);
3216 }
3217 if (!(tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)))
3218 {
3219 LOG(0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
3220 exit(1);
3221 }
3222 if (!(session = shared_malloc(sizeof(sessiont) * MAXSESSION)))
3223 {
3224 LOG(0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
3225 exit(1);
3226 }
3227
3228 if (!(sess_local = shared_malloc(sizeof(sessionlocalt) * MAXSESSION)))
3229 {
3230 LOG(0, 0, 0, "Error doing malloc for sess_local: %s\n", strerror(errno));
3231 exit(1);
3232 }
3233
3234 if (!(radius = shared_malloc(sizeof(radiust) * MAXRADIUS)))
3235 {
3236 LOG(0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
3237 exit(1);
3238 }
3239
3240 if (!(ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)))
3241 {
3242 LOG(0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
3243 exit(1);
3244 }
3245
3246 if (!(ip_filters = shared_malloc(sizeof(ip_filtert) * MAXFILTER)))
3247 {
3248 LOG(0, 0, 0, "Error doing malloc for ip_filters: %s\n", strerror(errno));
3249 exit(1);
3250 }
3251 memset(ip_filters, 0, sizeof(ip_filtert) * MAXFILTER);
3252
3253 if (!(cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION)))
3254 {
3255 LOG(0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
3256 exit(1);
3257 }
3258 memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
3259
3260 if (!(cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION)))
3261 {
3262 LOG(0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
3263 exit(1);
3264 }
3265 memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
3266
3267 memset(tunnel, 0, sizeof(tunnelt) * MAXTUNNEL);
3268 memset(session, 0, sizeof(sessiont) * MAXSESSION);
3269 memset(radius, 0, sizeof(radiust) * MAXRADIUS);
3270 memset(ip_address_pool, 0, sizeof(ippoolt) * MAXIPPOOL);
3271
3272 // Put all the sessions on the free list marked as undefined.
3273 for (i = 1; i < MAXSESSION; i++)
3274 {
3275 session[i].next = i + 1;
3276 session[i].tunnel = T_UNDEF; // mark it as not filled in.
3277 }
3278 session[MAXSESSION - 1].next = 0;
3279 sessionfree = 1;
3280
3281 // Mark all the tunnels as undefined (waiting to be filled in by a download).
3282 for (i = 1; i < MAXTUNNEL; i++)
3283 tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
3284
3285 if (!*hostname)
3286 {
3287 // Grab my hostname unless it's been specified
3288 gethostname(hostname, sizeof(hostname));
3289 stripdomain(hostname);
3290 }
3291
3292 _statistics->start_time = _statistics->last_reset = time(NULL);
3293
3294 #ifdef BGP
3295 if (!(bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)))
3296 {
3297 LOG(0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
3298 exit(1);
3299 }
3300 #endif /* BGP */
3301 }
3302
3303 static int assign_ip_address(sessionidt s)
3304 {
3305 uint32_t i;
3306 int best = -1;
3307 time_t best_time = time_now;
3308 char *u = session[s].user;
3309 char reuse = 0;
3310
3311
3312 CSTAT(assign_ip_address);
3313
3314 for (i = 1; i < ip_pool_size; i++)
3315 {
3316 if (!ip_address_pool[i].address || ip_address_pool[i].assigned)
3317 continue;
3318
3319 if (!session[s].walled_garden && ip_address_pool[i].user[0] && !strcmp(u, ip_address_pool[i].user))
3320 {
3321 best = i;
3322 reuse = 1;
3323 break;
3324 }
3325
3326 if (ip_address_pool[i].last < best_time)
3327 {
3328 best = i;
3329 if (!(best_time = ip_address_pool[i].last))
3330 break; // never used, grab this one
3331 }
3332 }
3333
3334 if (best < 0)
3335 {
3336 LOG(0, s, session[s].tunnel, "assign_ip_address(): out of addresses\n");
3337 return 0;
3338 }
3339
3340 session[s].ip = ip_address_pool[best].address;
3341 session[s].ip_pool_index = best;
3342 ip_address_pool[best].assigned = 1;
3343 ip_address_pool[best].last = time_now;
3344 ip_address_pool[best].session = s;
3345 if (session[s].walled_garden)
3346 /* Don't track addresses of users in walled garden (note: this
3347 means that their address isn't "sticky" even if they get
3348 un-gardened). */
3349 ip_address_pool[best].user[0] = 0;
3350 else
3351 strncpy(ip_address_pool[best].user, u, sizeof(ip_address_pool[best].user) - 1);
3352
3353 STAT(ip_allocated);
3354 LOG(4, s, session[s].tunnel, "assign_ip_address(): %s ip address %d from pool\n",
3355 reuse ? "Reusing" : "Allocating", best);
3356
3357 return 1;
3358 }
3359
3360 static void free_ip_address(sessionidt s)
3361 {
3362 int i = session[s].ip_pool_index;
3363
3364
3365 CSTAT(free_ip_address);
3366
3367 if (!session[s].ip)
3368 return; // what the?
3369
3370 if (i < 0) // Is this actually part of the ip pool?
3371 i = 0;
3372
3373 STAT(ip_freed);
3374 cache_ipmap(session[s].ip, -i); // Change the mapping to point back to the ip pool index.
3375 session[s].ip = 0;
3376 ip_address_pool[i].assigned = 0;
3377 ip_address_pool[i].session = 0;
3378 ip_address_pool[i].last = time_now;
3379 }
3380
3381 //
3382 // Fsck the address pool against the session table.
3383 // Normally only called when we become a master.
3384 //
3385 // This isn't perfect: We aren't keep tracking of which
3386 // users used to have an IP address.
3387 //
3388 void rebuild_address_pool(void)
3389 {
3390 int i;
3391
3392 //
3393 // Zero the IP pool allocation, and build
3394 // a map from IP address to pool index.
3395 for (i = 1; i < MAXIPPOOL; ++i)
3396 {
3397 ip_address_pool[i].assigned = 0;
3398 ip_address_pool[i].session = 0;
3399 if (!ip_address_pool[i].address)
3400 continue;
3401
3402 cache_ipmap(ip_address_pool[i].address, -i); // Map pool IP to pool index.
3403 }
3404
3405 for (i = 0; i < MAXSESSION; ++i)
3406 {
3407 int ipid;
3408 if (!(session[i].opened && session[i].ip))
3409 continue;
3410
3411 ipid = - lookup_ipmap(htonl(session[i].ip));
3412
3413 if (session[i].ip_pool_index < 0)
3414 {
3415 // Not allocated out of the pool.
3416 if (ipid < 1) // Not found in the pool either? good.
3417 continue;
3418
3419 LOG(0, i, 0, "Session %d has an IP address (%s) that was marked static, but is in the pool (%d)!\n",
3420 i, fmtaddr(session[i].ip, 0), ipid);
3421
3422 // Fall through and process it as part of the pool.
3423 }
3424
3425
3426 if (ipid > MAXIPPOOL || ipid < 0)
3427 {
3428 LOG(0, i, 0, "Session %d has a pool IP that's not found in the pool! (%d)\n", i, ipid);
3429 ipid = -1;
3430 session[i].ip_pool_index = ipid;
3431 continue;
3432 }
3433
3434 ip_address_pool[ipid].assigned = 1;
3435 ip_address_pool[ipid].session = i;
3436 ip_address_pool[ipid].last = time_now;
3437 strncpy(ip_address_pool[ipid].user, session[i].user, sizeof(ip_address_pool[ipid].user) - 1);
3438 session[i].ip_pool_index = ipid;
3439 cache_ipmap(session[i].ip, i); // Fix the ip map.
3440 }
3441 }
3442
3443 //
3444 // Fix the address pool to match a changed session.
3445 // (usually when the master sends us an update).
3446 static void fix_address_pool(int sid)
3447 {
3448 int ipid;
3449
3450 ipid = session[sid].ip_pool_index;
3451
3452 if (ipid > ip_pool_size)
3453 return; // Ignore it. rebuild_address_pool will fix it up.
3454
3455 if (ip_address_pool[ipid].address != session[sid].ip)
3456 return; // Just ignore it. rebuild_address_pool will take care of it.
3457
3458 ip_address_pool[ipid].assigned = 1;
3459 ip_address_pool[ipid].session = sid;
3460 ip_address_pool[ipid].last = time_now;
3461 strncpy(ip_address_pool[ipid].user, session[sid].user, sizeof(ip_address_pool[ipid].user) - 1);
3462 }
3463
3464 //
3465 // Add a block of addresses to the IP pool to hand out.
3466 //
3467 static void add_to_ip_pool(in_addr_t addr, in_addr_t mask)
3468 {
3469 int i;
3470 if (mask == 0)
3471 mask = 0xffffffff; // Host route only.
3472
3473 addr &= mask;
3474
3475 if (ip_pool_size >= MAXIPPOOL) // Pool is full!
3476 return ;
3477
3478 for (i = addr ;(i & mask) == addr; ++i)
3479 {
3480 if ((i & 0xff) == 0 || (i&0xff) == 255)
3481 continue; // Skip 0 and broadcast addresses.
3482
3483 ip_address_pool[ip_pool_size].address = i;
3484 ip_address_pool[ip_pool_size].assigned = 0;
3485 ++ip_pool_size;
3486 if (ip_pool_size >= MAXIPPOOL)
3487 {
3488 LOG(0, 0, 0, "Overflowed IP pool adding %s\n", fmtaddr(htonl(addr), 0));
3489 return;
3490 }
3491 }
3492 }
3493
3494 // Initialize the IP address pool
3495 static void initippool()
3496 {
3497 FILE *f;
3498 char *p;
3499 char buf[4096];
3500 memset(ip_address_pool, 0, sizeof(ip_address_pool));
3501
3502 if (!(f = fopen(IPPOOLFILE, "r")))
3503 {
3504 LOG(0, 0, 0, "Can't load pool file " IPPOOLFILE ": %s\n", strerror(errno));
3505 exit(1);
3506 }
3507
3508 while (ip_pool_size < MAXIPPOOL && fgets(buf, 4096, f))
3509 {
3510 char *pool = buf;
3511 buf[4095] = 0; // Force it to be zero terminated/
3512
3513 if (*buf == '#' || *buf == '\n')
3514 continue; // Skip comments / blank lines
3515 if ((p = (char *)strrchr(buf, '\n'))) *p = 0;
3516 if ((p = (char *)strchr(buf, ':')))
3517 {
3518 in_addr_t src;
3519 *p = '\0';
3520 src = inet_addr(buf);
3521 if (src == INADDR_NONE)
3522 {
3523 LOG(0, 0, 0, "Invalid address pool IP %s\n", buf);
3524 exit(1);
3525 }
3526 // This entry is for a specific IP only
3527 if (src != config->bind_address)
3528 continue;
3529 *p = ':';
3530 pool = p+1;
3531 }
3532 if ((p = (char *)strchr(pool, '/')))
3533 {
3534 // It's a range
3535 int numbits = 0;
3536 in_addr_t start = 0, mask = 0;
3537
3538 LOG(2, 0, 0, "Adding IP address range %s\n", buf);
3539 *p++ = 0;
3540 if (!*p || !(numbits = atoi(p)))
3541 {
3542 LOG(0, 0, 0, "Invalid pool range %s\n", buf);
3543 continue;
3544 }
3545 start = ntohl(inet_addr(pool));
3546 mask = (in_addr_t) (pow(2, numbits) - 1) << (32 - numbits);
3547
3548 // Add a static route for this pool
3549 LOG(5, 0, 0, "Adding route for address pool %s/%u\n",
3550 fmtaddr(htonl(start), 0), 32 + mask);
3551
3552 routeset(0, start, mask, 0, 1);
3553
3554 add_to_ip_pool(start, mask);
3555 }
3556 else
3557 {
3558 // It's a single ip address
3559 add_to_ip_pool(inet_addr(pool), 0);
3560 }
3561 }
3562 fclose(f);
3563 LOG(1, 0, 0, "IP address pool is %d addresses\n", ip_pool_size - 1);
3564 }
3565
3566 void snoop_send_packet(char *packet, uint16_t size, in_addr_t destination, uint16_t port)
3567 {
3568 struct sockaddr_in snoop_addr = {0};
3569 if (!destination || !port || snoopfd <= 0 || size <= 0 || !packet)
3570 return;
3571
3572 snoop_addr.sin_family = AF_INET;
3573 snoop_addr.sin_addr.s_addr = destination;
3574 snoop_addr.sin_port = ntohs(port);
3575
3576 LOG(5, 0, 0, "Snooping %d byte packet to %s:%d\n", size,
3577 fmtaddr(snoop_addr.sin_addr.s_addr, 0),
3578 htons(snoop_addr.sin_port));
3579
3580 if (sendto(snoopfd, packet, size, MSG_DONTWAIT | MSG_NOSIGNAL, (void *) &snoop_addr, sizeof(snoop_addr)) < 0)
3581 LOG(0, 0, 0, "Error sending intercept packet: %s\n", strerror(errno));
3582
3583 STAT(packets_snooped);
3584 }
3585
3586 static int dump_session(FILE **f, sessiont *s)
3587 {
3588 if (!s->opened || !s->ip || !(s->cin || s->cout) || !*s->user || s->walled_garden)
3589 return 1;
3590
3591 if (!*f)
3592 {
3593 char filename[1024];
3594 char timestr[64];
3595 time_t now = time(NULL);
3596
3597 strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&now));
3598 snprintf(filename, sizeof(filename), "%s/%s", config->accounting_dir, timestr);
3599
3600 if (!(*f = fopen(filename, "w")))
3601 {
3602 LOG(0, 0, 0, "Can't write accounting info to %s: %s\n", filename, strerror(errno));
3603 return 0;
3604 }
3605
3606 LOG(3, 0, 0, "Dumping accounting information to %s\n", filename);
3607 fprintf(*f, "# dslwatch.pl dump file V1.01\n"
3608 "# host: %s\n"
3609 "# time: %ld\n"
3610 "# uptime: %ld\n"
3611 "# format: username ip qos uptxoctets downrxoctets\n",
3612 hostname,
3613 now,
3614 now - basetime);
3615 }
3616
3617 LOG(4, 0, 0, "Dumping accounting information for %s\n", s->user);
3618 fprintf(*f, "%s %s %d %u %u\n",
3619 s->user, // username
3620 fmtaddr(htonl(s->ip), 0), // ip
3621 (s->throttle_in || s->throttle_out) ? 2 : 1, // qos
3622 (uint32_t) s->cin, // uptxoctets
3623 (uint32_t) s->cout); // downrxoctets
3624
3625 s->pin = s->cin = 0;
3626 s->pout = s->cout = 0;
3627
3628 return 1;
3629 }
3630
3631 static void dump_acct_info(int all)
3632 {
3633 int i;
3634 FILE *f = NULL;
3635
3636
3637 CSTAT(dump_acct_info);
3638
3639 if (shut_acct_n)
3640 {
3641 for (i = 0; i < shut_acct_n; i++)
3642 dump_session(&f, &shut_acct[i]);
3643
3644 shut_acct_n = 0;
3645 }
3646
3647 if (all)
3648 for (i = 1; i <= config->cluster_highest_sessionid; i++)
3649 dump_session(&f, &session[i]);
3650
3651 if (f)
3652 fclose(f);
3653 }
3654
3655 // Main program
3656 int main(int argc, char *argv[])
3657 {
3658 int i;
3659 int optdebug = 0;
3660 char *optconfig = CONFIGFILE;
3661
3662 time(&basetime); // start clock
3663
3664 // scan args
3665 while ((i = getopt(argc, argv, "dvc:h:")) >= 0)
3666 {
3667 switch (i)
3668 {
3669 case 'd':
3670 if (fork()) exit(0);
3671 setsid();
3672 freopen("/dev/null", "r", stdin);
3673 freopen("/dev/null", "w", stdout);
3674 freopen("/dev/null", "w", stderr);
3675 break;
3676 case 'v':
3677 optdebug++;
3678 break;
3679 case 'c':
3680 optconfig = optarg;
3681 break;
3682 case 'h':
3683 snprintf(hostname, sizeof(hostname), "%s", optarg);
3684 break;
3685 default:
3686 printf("Args are:\n"
3687 "\t-d\t\tDetach from terminal\n"
3688 "\t-c <file>\tConfig file\n"
3689 "\t-h <hostname>\tForce hostname\n"
3690 "\t-v\t\tDebug\n");
3691
3692 return (0);
3693 break;
3694 }
3695 }
3696
3697 // Start the timer routine off
3698 time(&time_now);
3699 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3700 signal(SIGALRM, sigalrm_handler);
3701 siginterrupt(SIGALRM, 0);
3702
3703 initplugins();
3704 initdata(optdebug, optconfig);
3705
3706 init_cli(hostname);
3707 read_config_file();
3708 init_tbf(config->num_tbfs);
3709
3710 LOG(0, 0, 0, "L2TPNS version " VERSION "\n");
3711 LOG(0, 0, 0, "Copyright (c) 2003, 2004, 2005 Optus Internet Engineering\n");
3712 LOG(0, 0, 0, "Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced\n");
3713 {
3714 struct rlimit rlim;
3715 rlim.rlim_cur = RLIM_INFINITY;
3716 rlim.rlim_max = RLIM_INFINITY;
3717 // Remove the maximum core size
3718 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
3719 LOG(0, 0, 0, "Can't set ulimit: %s\n", strerror(errno));
3720
3721 // Make core dumps go to /tmp
3722 chdir("/tmp");
3723 }
3724
3725 if (config->scheduler_fifo)
3726 {
3727 int ret;
3728 struct sched_param params = {0};
3729 params.sched_priority = 1;
3730
3731 if (get_nprocs() < 2)
3732 {
3733 LOG(0, 0, 0, "Not using FIFO scheduler, there is only 1 processor in the system.\n");
3734 config->scheduler_fifo = 0;
3735 }
3736 else
3737 {
3738 if ((ret = sched_setscheduler(0, SCHED_FIFO, &params)) == 0)
3739 {
3740 LOG(1, 0, 0, "Using FIFO scheduler. Say goodbye to any other processes running\n");
3741 }
3742 else
3743 {
3744 LOG(0, 0, 0, "Error setting scheduler to FIFO: %s\n", strerror(errno));
3745 config->scheduler_fifo = 0;
3746 }
3747 }
3748 }
3749
3750 /* Set up the cluster communications port. */
3751 if (cluster_init() < 0)
3752 exit(1);
3753
3754 #ifdef BGP
3755 signal(SIGPIPE, SIG_IGN);
3756 bgp_setup(config->as_number);
3757 bgp_add_route(config->bind_address, 0xffffffff);
3758 for (i = 0; i < BGP_NUM_PEERS; i++)
3759 {
3760 if (config->neighbour[i].name[0])
3761 bgp_start(&bgp_peers[i], config->neighbour[i].name,
3762 config->neighbour[i].as, config->neighbour[i].keepalive,
3763 config->neighbour[i].hold, 0); /* 0 = routing disabled */
3764 }
3765 #endif /* BGP */
3766
3767 inittun();
3768 LOG(1, 0, 0, "Set up on interface %s\n", config->tundevice);
3769
3770 initudp();
3771 initrad();
3772 initippool();
3773
3774 signal(SIGHUP, sighup_handler);
3775 signal(SIGTERM, sigterm_handler);
3776 signal(SIGINT, sigterm_handler);
3777 signal(SIGQUIT, sigquit_handler);
3778 signal(SIGCHLD, sigchild_handler);
3779
3780 // Prevent us from getting paged out
3781 if (config->lock_pages)
3782 {
3783 if (!mlockall(MCL_CURRENT))
3784 LOG(1, 0, 0, "Locking pages into memory\n");
3785 else
3786 LOG(0, 0, 0, "Can't lock pages: %s\n", strerror(errno));
3787 }
3788
3789 alarm(1);
3790
3791 // Drop privileges here
3792 if (config->target_uid > 0 && geteuid() == 0)
3793 setuid(config->target_uid);
3794
3795 mainloop();
3796
3797 #ifdef BGP
3798 /* try to shut BGP down cleanly; with luck the sockets will be
3799 writable since we're out of the select */
3800 for (i = 0; i < BGP_NUM_PEERS; i++)
3801 if (bgp_peers[i].state == Established)
3802 bgp_stop(&bgp_peers[i]);
3803 #endif /* BGP */
3804
3805 /* remove plugins (so cleanup code gets run) */
3806 plugins_done();
3807
3808 // Remove the PID file if we wrote it
3809 if (config->wrote_pid && *config->pid_file == '/')
3810 unlink(config->pid_file);
3811
3812 /* kill CLI children */
3813 signal(SIGTERM, SIG_IGN);
3814 kill(0, SIGTERM);
3815 return 0;
3816 }
3817
3818 static void sighup_handler(int sig)
3819 {
3820 if (log_stream)
3821 {
3822 if (log_stream != stderr)
3823 fclose(log_stream);
3824
3825 log_stream = NULL;
3826 }
3827
3828 read_config_file();
3829 }
3830
3831 static void sigalrm_handler(int sig)
3832 {
3833 // Log current traffic stats
3834
3835 snprintf(config->bandwidth, sizeof(config->bandwidth),
3836 "UDP-ETH:%1.0f/%1.0f ETH-UDP:%1.0f/%1.0f TOTAL:%0.1f IN:%u OUT:%u",
3837 (udp_rx / 1024.0 / 1024.0 * 8),
3838 (eth_tx / 1024.0 / 1024.0 * 8),
3839 (eth_rx / 1024.0 / 1024.0 * 8),
3840 (udp_tx / 1024.0 / 1024.0 * 8),
3841 ((udp_tx + udp_rx + eth_tx + eth_rx) / 1024.0 / 1024.0 * 8),
3842 udp_rx_pkt, eth_rx_pkt);
3843
3844 udp_tx = udp_rx = 0;
3845 udp_rx_pkt = eth_rx_pkt = 0;
3846 eth_tx = eth_rx = 0;
3847
3848 if (config->dump_speed)
3849 printf("%s\n", config->bandwidth);
3850
3851 // Update the internal time counter
3852 time(&time_now);
3853 strftime(time_now_string, sizeof(time_now_string), "%Y-%m-%d %H:%M:%S", localtime(&time_now));
3854 alarm(1);
3855
3856 {
3857 // Run timer hooks
3858 struct param_timer p = { time_now };
3859 run_plugins(PLUGIN_TIMER, &p);
3860 }
3861
3862 }
3863
3864 static void sigterm_handler(int sig)
3865 {
3866 LOG(1, 0, 0, "Shutting down cleanly\n");
3867 main_quit++;
3868 }
3869
3870 static void sigquit_handler(int sig)
3871 {
3872 int i;
3873
3874 LOG(1, 0, 0, "Shutting down without saving sessions\n");
3875
3876 if (config->cluster_iam_master)
3877 {
3878 for (i = 1; i < MAXSESSION; i++)
3879 {
3880 if (session[i].opened)
3881 sessionkill(i, "L2TPNS Closing");
3882 }
3883 for (i = 1; i < MAXTUNNEL; i++)
3884 {
3885 if (tunnel[i].ip || tunnel[i].state)
3886 tunnelshutdown(i, "L2TPNS Closing", 6, 0, 0);
3887 }
3888 }
3889
3890 main_quit++;
3891 }
3892
3893 static void sigchild_handler(int sig)
3894 {
3895 while (waitpid(-1, NULL, WNOHANG) > 0)
3896 ;
3897 }
3898
3899 static void build_chap_response(char *challenge, uint8_t id, uint16_t challenge_length, char **challenge_response)
3900 {
3901 MD5_CTX ctx;
3902 *challenge_response = NULL;
3903
3904 if (!*config->l2tpsecret)
3905 {
3906 LOG(0, 0, 0, "LNS requested CHAP authentication, but no l2tp secret is defined\n");
3907 return;
3908 }
3909
3910 LOG(4, 0, 0, " Building challenge response for CHAP request\n");
3911
3912 *challenge_response = (char *)calloc(17, 1);
3913
3914 MD5Init(&ctx);
3915 MD5Update(&ctx, &id, 1);
3916 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
3917 MD5Update(&ctx, challenge, challenge_length);
3918 MD5Final(*challenge_response, &ctx);
3919
3920 return;
3921 }
3922
3923 static int facility_value(char *name)
3924 {
3925 int i;
3926 for (i = 0; facilitynames[i].c_name; i++)
3927 {
3928 if (strcmp(facilitynames[i].c_name, name) == 0)
3929 return facilitynames[i].c_val;
3930 }
3931 return 0;
3932 }
3933
3934 static void update_config()
3935 {
3936 int i;
3937 char *p;
3938 static int timeout = 0;
3939 static int interval = 0;
3940
3941 // Update logging
3942 closelog();
3943 syslog_log = 0;
3944 if (log_stream)
3945 {
3946 if (log_stream != stderr)
3947 fclose(log_stream);
3948
3949 log_stream = NULL;
3950 }
3951
3952 if (*config->log_filename)
3953 {
3954 if (strstr(config->log_filename, "syslog:") == config->log_filename)
3955 {
3956 char *p = config->log_filename + 7;
3957 if (*p)
3958 {
3959 openlog("l2tpns", LOG_PID, facility_value(p));
3960 syslog_log = 1;
3961 }
3962 }
3963 else if (strchr(config->log_filename, '/') == config->log_filename)
3964 {
3965 if ((log_stream = fopen((char *)(config->log_filename), "a")))
3966 {
3967 fseek(log_stream, 0, SEEK_END);
3968 setbuf(log_stream, NULL);
3969 }
3970 else
3971 {
3972 log_stream = stderr;
3973 setbuf(log_stream, NULL);
3974 }
3975 }
3976 }
3977 else
3978 {
3979 log_stream = stderr;
3980 setbuf(log_stream, NULL);
3981 }
3982
3983 // Update radius
3984 config->numradiusservers = 0;
3985 for (i = 0; i < MAXRADSERVER; i++)
3986 if (config->radiusserver[i])
3987 {
3988 config->numradiusservers++;
3989 // Set radius port: if not set, take the port from the
3990 // first radius server. For the first radius server,
3991 // take the #defined default value from l2tpns.h
3992
3993 // test twice, In case someone works with
3994 // a secondary radius server without defining
3995 // a primary one, this will work even then.
3996 if (i > 0 && !config->radiusport[i])
3997 config->radiusport[i] = config->radiusport[i-1];
3998 if (!config->radiusport[i])
3999 config->radiusport[i] = RADPORT;
4000 }
4001
4002 if (!config->numradiusservers)
4003 LOG(0, 0, 0, "No RADIUS servers defined!\n");
4004
4005 config->num_radfds = 2 << RADIUS_SHIFT;
4006
4007 // parse radius_authtypes_s
4008 config->radius_authtypes = config->radius_authprefer = 0;
4009 p = config->radius_authtypes_s;
4010 while (p && *p)
4011 {
4012 char *s = strpbrk(p, " \t,");
4013 int type = 0;
4014
4015 if (s)
4016 {
4017 *s++ = 0;
4018 while (*s == ' ' || *s == '\t')
4019 s++;
4020
4021 if (!*s)
4022 s = 0;
4023 }
4024
4025 if (!strncasecmp("chap", p, strlen(p)))
4026 type = AUTHCHAP;
4027 else if (!strncasecmp("pap", p, strlen(p)))
4028 type = AUTHPAP;
4029 else
4030 LOG(0, 0, 0, "Invalid RADIUS authentication type \"%s\"\n", p);
4031
4032 config->radius_authtypes |= type;
4033 if (!config->radius_authprefer)
4034 config->radius_authprefer = type;
4035
4036 p = s;
4037 }
4038
4039 if (!config->radius_authtypes)
4040 {
4041 LOG(0, 0, 0, "Defaulting to PAP authentication\n");
4042 config->radius_authtypes = config->radius_authprefer = AUTHPAP;
4043 }
4044
4045 // normalise radius_authtypes_s
4046 if (config->radius_authprefer == AUTHPAP)
4047 {
4048 strcpy(config->radius_authtypes_s, "pap");
4049 if (config->radius_authtypes & AUTHCHAP)
4050 strcat(config->radius_authtypes_s, ", chap");
4051 }
4052 else
4053 {
4054 strcpy(config->radius_authtypes_s, "chap");
4055 if (config->radius_authtypes & AUTHPAP)
4056 strcat(config->radius_authtypes_s, ", pap");
4057 }
4058
4059 // re-initialise the random number source
4060 initrandom(config->random_device);
4061
4062 // Update plugins
4063 for (i = 0; i < MAXPLUGINS; i++)
4064 {
4065 if (strcmp(config->plugins[i], config->old_plugins[i]) == 0)
4066 continue;
4067
4068 if (*config->plugins[i])
4069 {
4070 // Plugin added
4071 add_plugin(config->plugins[i]);
4072 }
4073 else if (*config->old_plugins[i])
4074 {
4075 // Plugin removed
4076 remove_plugin(config->old_plugins[i]);
4077 }
4078 }
4079
4080 memcpy(config->old_plugins, config->plugins, sizeof(config->plugins));
4081 if (!config->cleanup_interval) config->cleanup_interval = 10;
4082 if (!config->multi_read_count) config->multi_read_count = 10;
4083 if (!config->cluster_address) config->cluster_address = inet_addr(DEFAULT_MCAST_ADDR);
4084 if (!*config->cluster_interface)
4085 strncpy(config->cluster_interface, DEFAULT_MCAST_INTERFACE, sizeof(config->cluster_interface) - 1);
4086
4087 if (!config->cluster_hb_interval)
4088 config->cluster_hb_interval = PING_INTERVAL; // Heartbeat every 0.5 seconds.
4089
4090 if (!config->cluster_hb_timeout)
4091 config->cluster_hb_timeout = HB_TIMEOUT; // 10 missed heartbeat triggers an election.
4092
4093 if (interval != config->cluster_hb_interval || timeout != config->cluster_hb_timeout)
4094 {
4095 // Paranoia: cluster_check_master() treats 2 x interval + 1 sec as
4096 // late, ensure we're sufficiently larger than that
4097 int t = 4 * config->cluster_hb_interval + 11;
4098
4099 if (config->cluster_hb_timeout < t)
4100 {
4101 LOG(0, 0, 0, "Heartbeat timeout %d too low, adjusting to %d\n", config->cluster_hb_timeout, t);
4102 config->cluster_hb_timeout = t;
4103 }
4104
4105 // Push timing changes to the slaves immediately if we're the master
4106 if (config->cluster_iam_master)
4107 cluster_heartbeat();
4108
4109 interval = config->cluster_hb_interval;
4110 timeout = config->cluster_hb_timeout;
4111 }
4112
4113 // Write PID file
4114 if (*config->pid_file == '/' && !config->wrote_pid)
4115 {
4116 FILE *f;
4117 if ((f = fopen(config->pid_file, "w")))
4118 {
4119 fprintf(f, "%d\n", getpid());
4120 fclose(f);
4121 config->wrote_pid = 1;
4122 }
4123 else
4124 {
4125 LOG(0, 0, 0, "Can't write to PID file %s: %s\n", config->pid_file, strerror(errno));
4126 }
4127 }
4128
4129 config->reload_config = 0;
4130 }
4131
4132 static void read_config_file()
4133 {
4134 FILE *f;
4135
4136 if (!config->config_file) return;
4137 if (!(f = fopen(config->config_file, "r")))
4138 {
4139 fprintf(stderr, "Can't open config file %s: %s\n", config->config_file, strerror(errno));
4140 return;
4141 }
4142
4143 LOG(3, 0, 0, "Reading config file %s\n", config->config_file);
4144 cli_do_file(f);
4145 LOG(3, 0, 0, "Done reading config file\n");
4146 fclose(f);
4147 update_config();
4148 }
4149
4150 int sessionsetup(tunnelidt t, sessionidt s)
4151 {
4152 // A session now exists, set it up
4153 in_addr_t ip;
4154 char *user;
4155 sessionidt i;
4156 int r;
4157
4158 CSTAT(sessionsetup);
4159
4160 LOG(3, s, t, "Doing session setup for session\n");
4161
4162 if (!session[s].ip)
4163 {
4164 assign_ip_address(s);
4165 if (!session[s].ip)
4166 {
4167 LOG(0, s, t, " No IP allocated. The IP address pool is FULL!\n");
4168 sessionshutdown(s, "No IP addresses available.", 2, 7);
4169 return 0;
4170 }
4171 LOG(3, s, t, " No IP allocated. Assigned %s from pool\n",
4172 fmtaddr(htonl(session[s].ip), 0));
4173 }
4174
4175
4176 // Make sure this is right
4177 session[s].tunnel = t;
4178
4179 // zap old sessions with same IP and/or username
4180 // Don't kill gardened sessions - doing so leads to a DoS
4181 // from someone who doesn't need to know the password
4182 {
4183 ip = session[s].ip;
4184 user = session[s].user;
4185 for (i = 1; i <= config->cluster_highest_sessionid; i++)
4186 {
4187 if (i == s) continue;
4188 if (ip == session[i].ip) sessionkill(i, "Duplicate IP address");
4189 if (!session[s].walled_garden && !session[i].walled_garden && strcasecmp(user, session[i].user) == 0)
4190 sessionkill(i, "Duplicate session for users");
4191 }
4192 }
4193
4194 {
4195 int routed = 0;
4196
4197 // Add the route for this session.
4198 for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
4199 {
4200 if ((session[s].ip & session[s].route[r].mask) ==
4201 (session[s].route[r].ip & session[s].route[r].mask))
4202 routed++;
4203
4204 routeset(s, session[s].route[r].ip, session[s].route[r].mask, 0, 1);
4205 }
4206
4207 // Static IPs need to be routed if not already
4208 // convered by a Framed-Route. Anything else is part
4209 // of the IP address pool and is already routed, it
4210 // just needs to be added to the IP cache.
4211 // IPv6 route setup is done in ppp.c, when IPV6CP is acked.
4212 if (session[s].ip_pool_index == -1) // static ip
4213 {
4214 if (!routed) routeset(s, session[s].ip, 0, 0, 1);
4215 }
4216 else
4217 cache_ipmap(session[s].ip, s);
4218 }
4219
4220 if (!session[s].unique_id)
4221 {
4222 // did this session just finish radius?
4223 LOG(3, s, t, "Sending initial IPCP to client\n");
4224 sendipcp(t, s);
4225 session[s].unique_id = ++last_id;
4226 }
4227
4228 // Run the plugin's against this new session.
4229 {
4230 struct param_new_session data = { &tunnel[t], &session[s] };
4231 run_plugins(PLUGIN_NEW_SESSION, &data);
4232 }
4233
4234 // Allocate TBFs if throttled
4235 if (session[s].throttle_in || session[s].throttle_out)
4236 throttle_session(s, session[s].throttle_in, session[s].throttle_out);
4237
4238 session[s].last_packet = time_now;
4239
4240 LOG(2, s, t, "Login by %s at %s from %s (%s)\n", session[s].user,
4241 fmtaddr(htonl(session[s].ip), 0),
4242 fmtaddr(htonl(tunnel[t].ip), 1), tunnel[t].hostname);
4243
4244 cluster_send_session(s); // Mark it as dirty, and needing to the flooded to the cluster.
4245
4246 return 1; // RADIUS OK and IP allocated, done...
4247 }
4248
4249 //
4250 // This session just got dropped on us by the master or something.
4251 // Make sure our tables up up to date...
4252 //
4253 int load_session(sessionidt s, sessiont *new)
4254 {
4255 int i;
4256 int newip = 0;
4257
4258 // Sanity checks.
4259 if (new->ip_pool_index >= MAXIPPOOL ||
4260 new->tunnel >= MAXTUNNEL)
4261 {
4262 LOG(0, s, 0, "Strange session update received!\n");
4263 // FIXME! What to do here?
4264 return 0;
4265 }
4266
4267 //
4268 // Ok. All sanity checks passed. Now we're committed to
4269 // loading the new session.
4270 //
4271
4272 session[s].tunnel = new->tunnel; // For logging in cache_ipmap
4273
4274 // See if routes/ip cache need updating
4275 if (new->ip != session[s].ip)
4276 newip++;
4277
4278 for (i = 0; !newip && i < MAXROUTE && (session[s].route[i].ip || new->route[i].ip); i++)
4279 if (new->route[i].ip != session[s].route[i].ip ||
4280 new->route[i].mask != session[s].route[i].mask)
4281 newip++;
4282
4283 // needs update
4284 if (newip)
4285 {
4286 int routed = 0;
4287
4288 // remove old routes...
4289 for (i = 0; i < MAXROUTE && session[s].route[i].ip; i++)
4290 {
4291 if ((session[s].ip & session[s].route[i].mask) ==
4292 (session[s].route[i].ip & session[s].route[i].mask))
4293 routed++;
4294
4295 routeset(s, session[s].route[i].ip, session[s].route[i].mask, 0, 0);
4296 }
4297
4298 // ...ip
4299 if (session[s].ip)
4300 {
4301 if (session[s].ip_pool_index == -1) // static IP
4302 {
4303 if (!routed) routeset(s, session[s].ip, 0, 0, 0);
4304 }
4305 else // It's part of the IP pool, remove it manually.
4306 uncache_ipmap(session[s].ip);
4307 }
4308
4309 routed = 0;
4310
4311 // add new routes...
4312 for (i = 0; i < MAXROUTE && new->route[i].ip; i++)
4313 {
4314 if ((new->ip & new->route[i].mask) ==
4315 (new->route[i].ip & new->route[i].mask))
4316 routed++;
4317
4318 routeset(s, new->route[i].ip, new->route[i].mask, 0, 1);
4319 }
4320
4321 // ...ip
4322 if (new->ip)
4323 {
4324 // If there's a new one, add it.
4325 if (new->ip_pool_index == -1)
4326 {
4327 if (!routed) routeset(s, new->ip, 0, 0, 1);
4328 }
4329 else
4330 cache_ipmap(new->ip, s);
4331 }
4332 }
4333
4334 // check v6 routing
4335 if (new->flags & SF_IPV6_ROUTED && !(session[s].flags & SF_IPV6_ROUTED))
4336 route6set(s, new->ipv6route, new->ipv6prefixlen, 1);
4337
4338 // check filters
4339 if (new->filter_in && (new->filter_in > MAXFILTER || !ip_filters[new->filter_in - 1].name[0]))
4340 {
4341 LOG(2, s, session[s].tunnel, "Dropping invalid input filter %d\n", (int) new->filter_in);
4342 new->filter_in = 0;
4343 }
4344
4345 if (new->filter_out && (new->filter_out > MAXFILTER || !ip_filters[new->filter_out - 1].name[0]))
4346 {
4347 LOG(2, s, session[s].tunnel, "Dropping invalid output filter %d\n", (int) new->filter_out);
4348 new->filter_out = 0;
4349 }
4350
4351 if (new->filter_in != session[s].filter_in)
4352 {
4353 if (session[s].filter_in) ip_filters[session[s].filter_in - 1].used--;
4354 if (new->filter_in) ip_filters[new->filter_in - 1].used++;
4355 }
4356
4357 if (new->filter_out != session[s].filter_out)
4358 {
4359 if (session[s].filter_out) ip_filters[session[s].filter_out - 1].used--;
4360 if (new->filter_out) ip_filters[new->filter_out - 1].used++;
4361 }
4362
4363 if (new->tunnel && s > config->cluster_highest_sessionid) // Maintain this in the slave. It's used
4364 // for walking the sessions to forward byte counts to the master.
4365 config->cluster_highest_sessionid = s;
4366
4367 // TEMP: old session struct used a uint32_t to define the throttle
4368 // speed for both up/down, new uses a uint16_t for each. Deal with
4369 // sessions from an old master for migration.
4370 if (new->throttle_out == 0 && new->tbf_out)
4371 new->throttle_out = new->throttle_in;
4372
4373 memcpy(&session[s], new, sizeof(session[s])); // Copy over..
4374
4375 // Do fixups into address pool.
4376 if (new->ip_pool_index != -1)
4377 fix_address_pool(s);
4378
4379 return 1;
4380 }
4381
4382 static void initplugins()
4383 {
4384 int i;
4385
4386 loaded_plugins = ll_init();
4387 // Initialize the plugins to nothing
4388 for (i = 0; i < MAX_PLUGIN_TYPES; i++)
4389 plugins[i] = ll_init();
4390 }
4391
4392 static void *open_plugin(char *plugin_name, int load)
4393 {
4394 char path[256] = "";
4395
4396 snprintf(path, 256, PLUGINDIR "/%s.so", plugin_name);
4397 LOG(2, 0, 0, "%soading plugin from %s\n", load ? "L" : "Un-l", path);
4398 return dlopen(path, RTLD_NOW);
4399 }
4400
4401 // plugin callback to get a config value
4402 static void *getconfig(char *key, enum config_typet type)
4403 {
4404 int i;
4405
4406 for (i = 0; config_values[i].key; i++)
4407 {
4408 if (!strcmp(config_values[i].key, key))
4409 {
4410 if (config_values[i].type == type)
4411 return ((void *) config) + config_values[i].offset;
4412
4413 LOG(1, 0, 0, "plugin requested config item \"%s\" expecting type %d, have type %d\n",
4414 key, type, config_values[i].type);
4415
4416 return 0;
4417 }
4418 }
4419
4420 LOG(1, 0, 0, "plugin requested unknown config item \"%s\"\n", key);
4421 return 0;
4422 }
4423
4424 static int add_plugin(char *plugin_name)
4425 {
4426 static struct pluginfuncs funcs = {
4427 _log,
4428 _log_hex,
4429 fmtaddr,
4430 sessionbyuser,
4431 sessiontbysessionidt,
4432 sessionidtbysessiont,
4433 radiusnew,
4434 radiussend,
4435 getconfig,
4436 sessionshutdown,
4437 sessionkill,
4438 throttle_session,
4439 cluster_send_session,
4440 };
4441
4442 void *p = open_plugin(plugin_name, 1);
4443 int (*initfunc)(struct pluginfuncs *);
4444 int i;
4445
4446 if (!p)
4447 {
4448 LOG(1, 0, 0, " Plugin load failed: %s\n", dlerror());
4449 return -1;
4450 }
4451
4452 if (ll_contains(loaded_plugins, p))
4453 {
4454 dlclose(p);
4455 return 0; // already loaded
4456 }
4457
4458 {
4459 int *v = dlsym(p, "plugin_api_version");
4460 if (!v || *v != PLUGIN_API_VERSION)
4461 {
4462 LOG(1, 0, 0, " Plugin load failed: API version mismatch: %s\n", dlerror());
4463 dlclose(p);
4464 return -1;
4465 }
4466 }
4467
4468 if ((initfunc = dlsym(p, "plugin_init")))
4469 {
4470 if (!initfunc(&funcs))
4471 {
4472 LOG(1, 0, 0, " Plugin load failed: plugin_init() returned FALSE: %s\n", dlerror());
4473 dlclose(p);
4474 return -1;
4475 }
4476 }
4477
4478 ll_push(loaded_plugins, p);
4479
4480 for (i = 0; i < max_plugin_functions; i++)
4481 {
4482 void *x;
4483 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4484 {
4485 LOG(3, 0, 0, " Supports function \"%s\"\n", plugin_functions[i]);
4486 ll_push(plugins[i], x);
4487 }
4488 }
4489
4490 LOG(2, 0, 0, " Loaded plugin %s\n", plugin_name);
4491 return 1;
4492 }
4493
4494 static void run_plugin_done(void *plugin)
4495 {
4496 int (*donefunc)(void) = dlsym(plugin, "plugin_done");
4497
4498 if (donefunc)
4499 donefunc();
4500 }
4501
4502 static int remove_plugin(char *plugin_name)
4503 {
4504 void *p = open_plugin(plugin_name, 0);
4505 int loaded = 0;
4506
4507 if (!p)
4508 return -1;
4509
4510 if (ll_contains(loaded_plugins, p))
4511 {
4512 int i;
4513 for (i = 0; i < max_plugin_functions; i++)
4514 {
4515 void *x;
4516 if (plugin_functions[i] && (x = dlsym(p, plugin_functions[i])))
4517 ll_delete(plugins[i], x);
4518 }
4519
4520 ll_delete(loaded_plugins, p);
4521 run_plugin_done(p);
4522 loaded = 1;
4523 }
4524
4525 dlclose(p);
4526 LOG(2, 0, 0, "Removed plugin %s\n", plugin_name);
4527 return loaded;
4528 }
4529
4530 int run_plugins(int plugin_type, void *data)
4531 {
4532 int (*func)(void *data);
4533
4534 if (!plugins[plugin_type] || plugin_type > max_plugin_functions)
4535 return PLUGIN_RET_ERROR;
4536
4537 ll_reset(plugins[plugin_type]);
4538 while ((func = ll_next(plugins[plugin_type])))
4539 {
4540 int r = func(data);
4541
4542 if (r != PLUGIN_RET_OK)
4543 return r; // stop here
4544 }
4545
4546 return PLUGIN_RET_OK;
4547 }
4548
4549 static void plugins_done()
4550 {
4551 void *p;
4552
4553 ll_reset(loaded_plugins);
4554 while ((p = ll_next(loaded_plugins)))
4555 run_plugin_done(p);
4556 }
4557
4558 static void processcontrol(uint8_t * buf, int len, struct sockaddr_in *addr, int alen)
4559 {
4560 struct nsctl request;
4561 struct nsctl response;
4562 int type = unpack_control(&request, buf, len);
4563 int r;
4564 void *p;
4565
4566 if (log_stream && config->debug >= 4)
4567 {
4568 if (type < 0)
4569 {
4570 LOG(4, 0, 0, "Bogus control message from %s (%d)\n",
4571 fmtaddr(addr->sin_addr.s_addr, 0), type);
4572 }
4573 else
4574 {
4575 LOG(4, 0, 0, "Received [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4576 dump_control(&request, log_stream);
4577 }
4578 }
4579
4580 switch (type)
4581 {
4582 case NSCTL_REQ_LOAD:
4583 if (request.argc != 1)
4584 {
4585 response.type = NSCTL_RES_ERR;
4586 response.argc = 1;
4587 response.argv[0] = "name of plugin required";
4588 }
4589 else if ((r = add_plugin(request.argv[0])) < 1)
4590 {
4591 response.type = NSCTL_RES_ERR;
4592 response.argc = 1;
4593 response.argv[0] = !r
4594 ? "plugin already loaded"
4595 : "error loading plugin";
4596 }
4597 else
4598 {
4599 response.type = NSCTL_RES_OK;
4600 response.argc = 0;
4601 }
4602
4603 break;
4604
4605 case NSCTL_REQ_UNLOAD:
4606 if (request.argc != 1)
4607 {
4608 response.type = NSCTL_RES_ERR;
4609 response.argc = 1;
4610 response.argv[0] = "name of plugin required";
4611 }
4612 else if ((r = remove_plugin(request.argv[0])) < 1)
4613 {
4614 response.type = NSCTL_RES_ERR;
4615 response.argc = 1;
4616 response.argv[0] = !r
4617 ? "plugin not loaded"
4618 : "plugin not found";
4619 }
4620 else
4621 {
4622 response.type = NSCTL_RES_OK;
4623 response.argc = 0;
4624 }
4625
4626 break;
4627
4628 case NSCTL_REQ_HELP:
4629 response.type = NSCTL_RES_OK;
4630 response.argc = 0;
4631
4632 ll_reset(loaded_plugins);
4633 while ((p = ll_next(loaded_plugins)))
4634 {
4635 char **help = dlsym(p, "plugin_control_help");
4636 while (response.argc < 0xff && help && *help)
4637 response.argv[response.argc++] = *help++;
4638 }
4639
4640 break;
4641
4642 case NSCTL_REQ_CONTROL:
4643 {
4644 struct param_control param = {
4645 config->cluster_iam_master,
4646 request.argc,
4647 request.argv,
4648 0,
4649 NULL,
4650 };
4651
4652 int r = run_plugins(PLUGIN_CONTROL, &param);
4653
4654 if (r == PLUGIN_RET_ERROR)
4655 {
4656 response.type = NSCTL_RES_ERR;
4657 response.argc = 1;
4658 response.argv[0] = param.additional
4659 ? param.additional
4660 : "error returned by plugin";
4661 }
4662 else if (r == PLUGIN_RET_NOTMASTER)
4663 {
4664 static char msg[] = "must be run on master: 000.000.000.000";
4665
4666 response.type = NSCTL_RES_ERR;
4667 response.argc = 1;
4668 if (config->cluster_master_address)
4669 {
4670 strcpy(msg + 23, fmtaddr(config->cluster_master_address, 0));
4671 response.argv[0] = msg;
4672 }
4673 else
4674 {
4675 response.argv[0] = "must be run on master: none elected";
4676 }
4677 }
4678 else if (!(param.response & NSCTL_RESPONSE))
4679 {
4680 response.type = NSCTL_RES_ERR;
4681 response.argc = 1;
4682 response.argv[0] = param.response
4683 ? "unrecognised response value from plugin"
4684 : "unhandled action";
4685 }
4686 else
4687 {
4688 response.type = param.response;
4689 response.argc = 0;
4690 if (param.additional)
4691 {
4692 response.argc = 1;
4693 response.argv[0] = param.additional;
4694 }
4695 }
4696 }
4697
4698 break;
4699
4700 default:
4701 response.type = NSCTL_RES_ERR;
4702 response.argc = 1;
4703 response.argv[0] = "error unpacking control packet";
4704 }
4705
4706 buf = calloc(NSCTL_MAX_PKT_SZ, 1);
4707 if (!buf)
4708 {
4709 LOG(2, 0, 0, "Failed to allocate nsctl response\n");
4710 return;
4711 }
4712
4713 r = pack_control(buf, NSCTL_MAX_PKT_SZ, response.type, response.argc, response.argv);
4714 if (r > 0)
4715 {
4716 sendto(controlfd, buf, r, 0, (const struct sockaddr *) addr, alen);
4717 if (log_stream && config->debug >= 4)
4718 {
4719 LOG(4, 0, 0, "Sent [%s] ", fmtaddr(addr->sin_addr.s_addr, 0));
4720 dump_control(&response, log_stream);
4721 }
4722 }
4723 else
4724 LOG(2, 0, 0, "Failed to pack nsctl response for %s (%d)\n",
4725 fmtaddr(addr->sin_addr.s_addr, 0), r);
4726
4727 free(buf);
4728 }
4729
4730 static tunnelidt new_tunnel()
4731 {
4732 tunnelidt i;
4733 for (i = 1; i < MAXTUNNEL; i++)
4734 {
4735 if (tunnel[i].state == TUNNELFREE)
4736 {
4737 LOG(4, 0, i, "Assigning tunnel ID %d\n", i);
4738 if (i > config->cluster_highest_tunnelid)
4739 config->cluster_highest_tunnelid = i;
4740 return i;
4741 }
4742 }
4743 LOG(0, 0, 0, "Can't find a free tunnel! There shouldn't be this many in use!\n");
4744 return 0;
4745 }
4746
4747 //
4748 // We're becoming the master. Do any required setup..
4749 //
4750 // This is principally telling all the plugins that we're
4751 // now a master, and telling them about all the sessions
4752 // that are active too..
4753 //
4754 void become_master(void)
4755 {
4756 int s, i;
4757 run_plugins(PLUGIN_BECOME_MASTER, NULL);
4758
4759 // running a bunch of iptables commands is slow and can cause
4760 // the master to drop tunnels on takeover--kludge around the
4761 // problem by forking for the moment (note: race)
4762 if (!fork_and_close())
4763 {
4764 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4765 {
4766 if (!session[s].opened) // Not an in-use session.
4767 continue;
4768
4769 run_plugins(PLUGIN_NEW_SESSION_MASTER, &session[s]);
4770 }
4771 exit(0);
4772 }
4773
4774 // add radius fds
4775 for (i = 0; i < config->num_radfds; i++)
4776 {
4777 FD_SET(radfds[i], &readset);
4778 if (radfds[i] > readset_n)
4779 readset_n = radfds[i];
4780 }
4781 }
4782
4783 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc)
4784 {
4785 int s, i;
4786 int count = 0;
4787 int buckets[64];
4788
4789 if (CLI_HELP_REQUESTED)
4790 return CLI_HELP_NO_ARGS;
4791
4792 time(&time_now);
4793 for (i = 0; i < 64;++i) buckets[i] = 0;
4794
4795 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4796 {
4797 int idle;
4798 if (!session[s].opened)
4799 continue;
4800
4801 idle = time_now - session[s].last_packet;
4802 idle /= 5 ; // In multiples of 5 seconds.
4803 if (idle < 0)
4804 idle = 0;
4805 if (idle > 63)
4806 idle = 63;
4807
4808 ++count;
4809 ++buckets[idle];
4810 }
4811
4812 for (i = 0; i < 63; ++i)
4813 {
4814 cli_print(cli, "%3d seconds : %7.2f%% (%6d)", i * 5, (double) buckets[i] * 100.0 / count , buckets[i]);
4815 }
4816 cli_print(cli, "lots of secs : %7.2f%% (%6d)", (double) buckets[63] * 100.0 / count , buckets[i]);
4817 cli_print(cli, "%d total sessions open.", count);
4818 return CLI_OK;
4819 }
4820
4821 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc)
4822 {
4823 int s, i;
4824 int count = 0;
4825 int buckets[64];
4826
4827 if (CLI_HELP_REQUESTED)
4828 return CLI_HELP_NO_ARGS;
4829
4830 time(&time_now);
4831 for (i = 0; i < 64;++i) buckets[i] = 0;
4832
4833 for (s = 1; s <= config->cluster_highest_sessionid ; ++s)
4834 {
4835 int open = 0, d;
4836 if (!session[s].opened)
4837 continue;
4838
4839 d = time_now - session[s].opened;
4840 if (d < 0)
4841 d = 0;
4842 while (d > 1 && open < 32)
4843 {
4844 ++open;
4845 d >>= 1; // half.
4846 }
4847 ++count;
4848 ++buckets[open];
4849 }
4850
4851 s = 1;
4852 for (i = 0; i < 30; ++i)
4853 {
4854 cli_print(cli, " < %8d seconds : %7.2f%% (%6d)", s, (double) buckets[i] * 100.0 / count , buckets[i]);
4855 s <<= 1;
4856 }
4857 cli_print(cli, "%d total sessions open.", count);
4858 return CLI_OK;
4859 }
4860
4861 /* Unhide an avp.
4862 *
4863 * This unencodes the AVP using the L2TP secret and the previously
4864 * stored random vector. It overwrites the hidden data with the
4865 * unhidden AVP subformat.
4866 */
4867 static void unhide_value(uint8_t *value, size_t len, uint16_t type, uint8_t *vector, size_t vec_len)
4868 {
4869 MD5_CTX ctx;
4870 uint8_t digest[16];
4871 uint8_t *last;
4872 size_t d = 0;
4873
4874 // Compute initial pad
4875 MD5Init(&ctx);
4876 MD5Update(&ctx, (uint8_t) (type >> 8) & 0xff, 1);
4877 MD5Update(&ctx, (uint8_t) type & 0xff, 1);
4878 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4879 MD5Update(&ctx, vector, vec_len);
4880 MD5Final(digest, &ctx);
4881
4882 // pointer to last decoded 16 octets
4883 last = value;
4884
4885 while (len > 0)
4886 {
4887 // calculate a new pad based on the last decoded block
4888 if (d >= sizeof(digest))
4889 {
4890 MD5Init(&ctx);
4891 MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
4892 MD5Update(&ctx, last, sizeof(digest));
4893 MD5Final(digest, &ctx);
4894
4895 d = 0;
4896 last = value;
4897 }
4898
4899 *value++ ^= digest[d++];
4900 len--;
4901 }
4902 }
4903
4904 static int ip_filter_port(ip_filter_portt *p, uint16_t port)
4905 {
4906 switch (p->op)
4907 {
4908 case FILTER_PORT_OP_EQ: return port == p->port;
4909 case FILTER_PORT_OP_NEQ: return port != p->port;
4910 case FILTER_PORT_OP_GT: return port > p->port;
4911 case FILTER_PORT_OP_LT: return port < p->port;
4912 case FILTER_PORT_OP_RANGE: return port >= p->port && port <= p->port2;
4913 }
4914
4915 return 0;
4916 }
4917
4918 static int ip_filter_flag(uint8_t op, uint8_t sflags, uint8_t cflags, uint8_t flags)
4919 {
4920 switch (op)
4921 {
4922 case FILTER_FLAG_OP_ANY:
4923 return (flags & sflags) || (~flags & cflags);
4924
4925 case FILTER_FLAG_OP_ALL:
4926 return (flags & sflags) == sflags && (~flags & cflags) == cflags;
4927
4928 case FILTER_FLAG_OP_EST:
4929 return (flags & (TCP_FLAG_ACK|TCP_FLAG_RST)) && (~flags & TCP_FLAG_SYN);
4930 }
4931
4932 return 0;
4933 }
4934
4935 int ip_filter(uint8_t *buf, int len, uint8_t filter)
4936 {
4937 uint16_t frag_offset;
4938 uint8_t proto;
4939 in_addr_t src_ip;
4940 in_addr_t dst_ip;
4941 uint16_t src_port = 0;
4942 uint16_t dst_port = 0;
4943 uint8_t flags = 0;
4944 ip_filter_rulet *rule;
4945
4946 if (len < 20) // up to end of destination address
4947 return 0;
4948
4949 if ((*buf >> 4) != 4) // IPv4
4950 return 0;
4951
4952 frag_offset = ntohs(*(uint16_t *) (buf + 6)) & 0x1fff;
4953 proto = buf[9];
4954 src_ip = *(in_addr_t *) (buf + 12);
4955 dst_ip = *(in_addr_t *) (buf + 16);
4956
4957 if (frag_offset == 0 && (proto == IPPROTO_TCP || proto == IPPROTO_UDP))
4958 {
4959 int l = (buf[0] & 0xf) * 4; // length of IP header
4960 if (len < l + 4) // ports
4961 return 0;
4962
4963 src_port = ntohs(*(uint16_t *) (buf + l));
4964 dst_port = ntohs(*(uint16_t *) (buf + l + 2));
4965 if (proto == IPPROTO_TCP)
4966 {
4967 if (len < l + 14) // flags
4968 return 0;
4969
4970 flags = buf[l + 13] & 0x3f;
4971 }
4972 }
4973
4974 for (rule = ip_filters[filter].rules; rule->action; rule++)
4975 {
4976 if (rule->proto != IPPROTO_IP && proto != rule->proto)
4977 continue;
4978
4979 if (rule->src_wild != INADDR_BROADCAST &&
4980 (src_ip & ~rule->src_wild) != (rule->src_ip & ~rule->src_wild))
4981 continue;
4982
4983 if (rule->dst_wild != INADDR_BROADCAST &&
4984 (dst_ip & ~rule->dst_wild) != (rule->dst_ip & ~rule->dst_wild))
4985 continue;
4986
4987 if (frag_offset)
4988 {
4989 if (!rule->frag || rule->action == FILTER_ACTION_DENY)
4990 continue;
4991 }
4992 else
4993 {
4994 if (rule->frag)
4995 continue;
4996
4997 if (proto == IPPROTO_TCP || proto == IPPROTO_UDP)
4998 {
4999 if (rule->src_ports.op && !ip_filter_port(&rule->src_ports, src_port))
5000 continue;
5001
5002 if (rule->dst_ports.op && !ip_filter_port(&rule->dst_ports, dst_port))
5003 continue;
5004
5005 if (proto == IPPROTO_TCP && rule->tcp_flag_op &&
5006 !ip_filter_flag(rule->tcp_flag_op, rule->tcp_sflags, rule->tcp_cflags, flags))
5007 continue;
5008 }
5009 }
5010
5011 // matched
5012 rule->counter++;
5013 return rule->action == FILTER_ACTION_PERMIT;
5014 }
5015
5016 // default deny
5017 return 0;
5018 }