oop
[l2tpns.git] / l2tpns.h
1 // L2TPNS Global Stuff
2 // $Id: l2tpns.h,v 1.37 2004-11-25 12:41:35 bodea Exp $
3
4 #ifndef __L2TPNS_H__
5 #define __L2TPNS_H__
6
7 #include <netinet/in.h>
8 #include <execinfo.h>
9 #include <stdio.h>
10 #include <signal.h>
11 #include <stdlib.h>
12 #include <netinet/in.h>
13 #include <sys/socket.h>
14 #include <arpa/inet.h>
15 #include <sys/types.h>
16 #include <libcli.h>
17
18 #define VERSION "2.0.9"
19
20 // Limits
21 #define MAXTUNNEL 500 // could be up to 65535
22 #define MAXSESSION 50000 // could be up to 65535
23 #define MAXTBFS 6000 // Maximum token bucket filters. Might need up to 2 * session.
24
25 #define RADIUS_SHIFT 5
26 #define RADIUS_MASK ((unsigned short)(((unsigned short)~0) >> (16 - RADIUS_SHIFT)))
27 #define MAXRADIUS ((unsigned long)(1L << RADIUS_SHIFT) * 255)
28
29 #define T_UNDEF (0xffff) // A tunnel ID that won't ever be used. Mark session as undefined.
30 #define T_FREE (0) // A tunnel ID that won't ever be used. Mark session as free.
31
32 #define MAXCONTROL 1000 // max length control message we ever send...
33 #define MAXETHER (1500+18) // max packet we try sending to tun
34 #define MAXTEL 96 // telephone number
35 #define MAXPLUGINS 20 // maximum number of plugins to load
36 #define MAXRADSERVER 10 // max radius servers
37 #define MAXROUTE 10 // max static routes per session
38 #define MAXIPPOOL 131072 // max number of ip addresses in pool
39 #define RINGBUFFER_SIZE 10000 // Number of ringbuffer entries to allocate
40 #define MAX_LOG_LENGTH 512 // Maximum size of log message
41 #define ECHO_TIMEOUT 60 // Time between last packet sent and LCP ECHO generation
42 #define IDLE_TIMEOUT 240 // Time between last packet sent and LCP ECHO generation
43 #define BUSY_WAIT_TIME 3000 // 5 minutes in 1/10th seconds to wait for radius to cleanup on shutdown
44
45 // Constants
46 #ifndef ETCDIR
47 #define ETCDIR "/etc/l2tpns"
48 #endif
49
50 #ifndef LIBDIR
51 #define LIBDIR "/usr/lib/l2tpns"
52 #endif
53
54 #ifndef STATEDIR
55 #define STATEDIR "/var/lib/l2tpns"
56 #endif
57
58 #ifndef PLUGINDIR
59 #define PLUGINDIR LIBDIR // Plugins
60 #endif
61
62 #ifndef PLUGINCONF
63 #define PLUGINCONF ETCDIR // Plugin config dir
64 #endif
65
66 #ifndef FLASHDIR
67 #define FLASHDIR ETCDIR
68 #endif
69
70 #ifndef DATADIR
71 #define DATADIR STATEDIR
72 #endif
73
74 #define TUNDEVICE "/dev/net/tun"
75 #define STATEFILE DATADIR "/state.dump" // State dump file
76 #define CONFIGFILE FLASHDIR "/startup-config" // Configuration file
77 #define CLIUSERS FLASHDIR "/users" // CLI Users file
78 #define IPPOOLFILE FLASHDIR "/ip_pool" // Address pool configuration
79 #define ACCT_TIME 3000 // 5 minute accounting interval
80 #define L2TPPORT 1701 // L2TP port
81 #define RADPORT 1645 // old radius port...
82 #define PKTARP 0x0806 // ARP packet type
83 #define PKTIP 0x0800 // IP packet type
84 #define PSEUDOMAC 0x0200 // pseudo MAC prefix (local significant MAC)
85 #define PPPPAP 0xC023
86 #define PPPCHAP 0xC223
87 #define PPPLCP 0xC021
88 #define PPPIPCP 0x8021
89 #define PPPCCP 0x80FD
90 #define PPPIP 0x0021
91 #define PPPMP 0x003D
92 #define MIN_IP_SIZE 0x19
93 enum
94 {
95 ConfigReq = 1,
96 ConfigAck,
97 ConfigNak,
98 ConfigRej,
99 TerminateReq,
100 TerminateAck,
101 CodeRej,
102 ProtocolRej,
103 EchoReq,
104 EchoReply,
105 DiscardRequest,
106 IdentRequest
107 };
108
109 // Types
110 typedef unsigned short u16;
111 typedef unsigned int u32;
112 typedef unsigned char u8;
113 typedef u32 ipt;
114 typedef u16 portt;
115 typedef u16 sessionidt;
116 typedef u16 tunnelidt;
117 typedef u32 clockt;
118 typedef u8 hasht[16];
119
120 // CLI actions
121 struct cli_session_actions {
122 char action;
123 ipt snoop_ip;
124 u16 snoop_port;
125 int throttle_in;
126 int throttle_out;
127 };
128
129 #define CLI_SESS_KILL 0x01
130 #define CLI_SESS_SNOOP 0x02
131 #define CLI_SESS_NOSNOOP 0x04
132 #define CLI_SESS_THROTTLE 0x08
133 #define CLI_SESS_NOTHROTTLE 0x10
134
135 struct cli_tunnel_actions {
136 char action;
137 };
138
139 #define CLI_TUN_KILL 0x01
140
141 // dump header: update number if internal format changes
142 #define DUMP_MAGIC "L2TPNS#" VERSION "#"
143
144 // structures
145 typedef struct routes // route
146 {
147 ipt ip;
148 ipt mask;
149 }
150 routet;
151
152 typedef struct controls // control message
153 {
154 struct controls *next; // next in queue
155 u16 length; // length
156 u8 buf[MAXCONTROL];
157 }
158 controlt;
159
160 typedef struct sessions
161 {
162 sessionidt next; // next session in linked list
163 sessionidt far; // far end session ID
164 tunnelidt tunnel; // near end tunnel ID
165 ipt ip; // IP of session set by RADIUS response (host byte order).
166 int ip_pool_index; // index to IP pool
167 unsigned long unique_id; // unique session id
168 u16 nr; // next receive
169 u16 ns; // next send
170 u32 magic; // ppp magic number
171 u32 cin, cout; // byte counts
172 u32 pin, pout; // packet counts
173 u32 total_cin; // This counter is never reset while a session is open
174 u32 total_cout; // This counter is never reset while a session is open
175 u32 id; // session id
176 u16 throttle_in; // upstream throttle rate (kbps)
177 u16 throttle_out; // downstream throttle rate
178 clockt opened; // when started
179 clockt die; // being closed, when to finally free
180 time_t last_packet; // Last packet from the user (used for idle timeouts)
181 ipt dns1, dns2; // DNS servers
182 routet route[MAXROUTE]; // static routes
183 u16 radius; // which radius session is being used (0 for not waiting on authentication)
184 u16 mru; // maximum receive unit
185 u16 tbf_in; // filter bucket for throttling in from the user.
186 u16 tbf_out; // filter bucket for throttling out to the user.
187 u8 l2tp_flags; // various bit flags from the ICCN on the l2tp tunnel.
188 u8 reserved_old_snoop; // No longer used - remove at some time
189 u8 walled_garden; // is this session gardened?
190 u8 flags1; // additional flags (currently unused);
191 char random_vector[MAXTEL];
192 int random_vector_length;
193 char user[129]; // user (needed in seesion for radius stop messages) (can we reduce this? --mo)
194 char called[MAXTEL]; // called number
195 char calling[MAXTEL]; // calling number
196 u32 tx_connect_speed;
197 u32 rx_connect_speed;
198 u32 flags; // Various session flags.
199 ipt snoop_ip; // Interception destination IP
200 u16 snoop_port; // Interception destination port
201 u16 sid; // near end session id.
202 char reserved[20]; // Space to expand structure without changing HB_VERSION
203 }
204 sessiont;
205
206 #define SF_IPCP_ACKED 1 // Has this session seen an IPCP Ack?
207 #define SF_LCP_ACKED 2 // LCP negotiated
208 #define SF_CCP_ACKED 4 // CCP negotiated
209
210 typedef struct {
211 u32 cin;
212 u32 cout;
213 } sessioncountt;
214
215 #define SESSIONPFC 1 // PFC negotiated flags
216 #define SESSIONACFC 2 // ACFC negotiated flags
217
218 // 168 bytes per tunnel
219 typedef struct tunnels
220 {
221 tunnelidt far; // far end tunnel ID
222 ipt ip; // Ip for far end
223 portt port; // port for far end
224 u16 window; // Rx window
225 u16 nr; // next receive
226 u16 ns; // next send
227 int state; // current state (tunnelstate enum)
228 clockt last; // when last control message sent (used for resend timeout)
229 clockt retry; // when to try resenting pending control
230 clockt die; // being closed, when to finally free
231 clockt lastrec; // when the last control message was received
232 char hostname[128]; // tunnel hostname
233 char vendor[128]; // LAC vendor
234 u8 try; // number of retrys on a control message
235 u16 controlc; // outstaind messages in queue
236 controlt *controls; // oldest message
237 controlt *controle; // newest message
238 }
239 tunnelt;
240
241 // 180 bytes per radius session
242 typedef struct radiuss // outstanding RADIUS requests
243 {
244 sessionidt session; // which session this applies to
245 hasht auth; // request authenticator
246 clockt retry; // when to try next
247 char calling[MAXTEL]; // calling number
248 char pass[129]; // password
249 u8 id; // ID for PPP response
250 u8 try; // which try we are on
251 u8 state; // state of radius requests
252 u8 chap; // set if CHAP used (is CHAP identifier)
253 }
254 radiust;
255
256 typedef struct
257 {
258 ipt address; // Host byte order..
259 char assigned; // 1 if assigned, 0 if free
260 sessionidt session;
261 clockt last; // last used
262 char user[129]; // user (try to have ip addresses persistent)
263 }
264 ippoolt;
265
266 #ifdef RINGBUFFER
267 struct Tringbuffer
268 {
269 struct {
270 char level;
271 sessionidt session;
272 tunnelidt tunnel;
273 ipt address;
274 char message[MAX_LOG_LENGTH];
275 } buffer[RINGBUFFER_SIZE];
276 int head;
277 int tail;
278 };
279 #endif
280
281 /*
282 * Possible tunnel states
283 * TUNNELFREE -> TUNNELOPEN -> TUNNELDIE -> TUNNELFREE
284 */
285 enum
286 {
287 TUNNELFREE, // Not in use
288 TUNNELOPEN, // Active tunnel
289 TUNNELDIE, // Currently closing
290 TUNNELOPENING, // Busy opening
291 TUNNELUNDEF, // Undefined
292 };
293
294 enum
295 {
296 RADIUSNULL, // Not in use
297 RADIUSCHAP, // sending CHAP down PPP
298 RADIUSAUTH, // sending auth to RADIUS server
299 RADIUSIPCP, // sending IPCP to end user
300 RADIUSSTART, // sending start accounting to RADIUS server
301 RADIUSSTOP, // sending stop accounting to RADIUS server
302 RADIUSWAIT, // waiting timeout before available, in case delayed replies
303 RADIUSDEAD, // errored while talking to radius server.
304 };
305
306 struct Tstats
307 {
308 time_t start_time;
309 time_t last_reset;
310
311 unsigned long tun_rx_packets;
312 unsigned long tun_tx_packets;
313 unsigned long tun_rx_bytes;
314 unsigned long tun_tx_bytes;
315 unsigned long tun_rx_errors;
316 unsigned long tun_tx_errors;
317
318 unsigned long tunnel_rx_packets;
319 unsigned long tunnel_tx_packets;
320 unsigned long tunnel_rx_bytes;
321 unsigned long tunnel_tx_bytes;
322 unsigned long tunnel_rx_errors;
323 unsigned long tunnel_tx_errors;
324
325 unsigned long tunnel_retries;
326 unsigned long radius_retries;
327
328 unsigned long arp_sent;
329
330 unsigned long packets_snooped;
331
332 unsigned long tunnel_created;
333 unsigned long session_created;
334 unsigned long tunnel_timeout;
335 unsigned long session_timeout;
336 unsigned long radius_timeout;
337 unsigned long radius_overflow;
338 unsigned long tunnel_overflow;
339 unsigned long session_overflow;
340
341 unsigned long ip_allocated;
342 unsigned long ip_freed;
343
344 unsigned long c_forwarded;
345 unsigned long recv_forward;
346 #ifdef STATISTICS
347 unsigned long call_processtun;
348 unsigned long call_processipout;
349 unsigned long call_processudp;
350 unsigned long call_sessionbyip;
351 unsigned long call_sessionbyuser;
352 unsigned long call_sendarp;
353 unsigned long call_sendipcp;
354 unsigned long call_tunnelsend;
355 unsigned long call_sessionkill;
356 unsigned long call_sessionshutdown;
357 unsigned long call_tunnelkill;
358 unsigned long call_tunnelshutdown;
359 unsigned long call_assign_ip_address;
360 unsigned long call_free_ip_address;
361 unsigned long call_dump_acct_info;
362 unsigned long call_sessionsetup;
363 unsigned long call_processpap;
364 unsigned long call_processchap;
365 unsigned long call_processlcp;
366 unsigned long call_processipcp;
367 unsigned long call_processipin;
368 unsigned long call_processccp;
369 unsigned long call_sendchap;
370 unsigned long call_processrad;
371 unsigned long call_radiussend;
372 unsigned long call_radiusretry;
373 #endif
374 };
375
376 #ifdef STATISTICS
377
378 #ifdef STAT_CALLS
379 #define CSTAT(x) STAT(x)
380 #else
381 #define CSTAT(x)
382 #endif
383
384 #define STAT(x) (_statistics->x++)
385 #define INC_STAT(x,y) (_statistics->x += (y))
386 #define GET_STAT(x) (_statistics->x)
387 #define SET_STAT(x, y) (_statistics->x = (y))
388 #else
389 #define CSTAT(x)
390 #define STAT(x)
391 #define INC_STAT(x,y)
392 #define GET_STAT(x) 0
393 #define SET_STAT(x, y)
394 #endif
395
396 struct configt
397 {
398 int debug; // debugging level
399 time_t start_time; // time when l2tpns was started
400 char bandwidth[256]; // current bandwidth
401 char pid_file[256]; // file to write PID to on startup
402 int wrote_pid;
403 clockt current_time; // 1/10ths of a second since the process started.
404 // means that we can only run a given process
405 // for 13 years without re-starting!
406
407 char config_file[128];
408 int reload_config; // flag to re-read config (set by cli)
409 int cleanup_interval; // interval between regular cleanups (in seconds)
410 int multi_read_count; // amount of packets to read per fd in processing loop
411
412 char tundevice[10]; // tun device name
413 char log_filename[128];
414 char l2tpsecret[64];
415
416 char radiussecret[64];
417 int radius_accounting;
418 ipt radiusserver[MAXRADSERVER]; // radius servers
419 u16 radiusport[MAXRADSERVER]; // radius base ports
420 u8 numradiusservers; // radius server count
421 short num_radfds; // Number of radius filehandles allocated
422
423 ipt default_dns1, default_dns2;
424
425 unsigned long rl_rate; // default throttle rate
426 int num_tbfs; // number of throttle buckets
427
428 int save_state;
429 char accounting_dir[128];
430 ipt bind_address;
431 ipt peer_address;
432 int send_garp; // Set to true to garp for vip address on startup
433
434 int target_uid;
435 int dump_speed;
436 char plugins[64][MAXPLUGINS];
437 char old_plugins[64][MAXPLUGINS];
438
439 int next_tbf; // Next HTB id available to use
440 int scheduler_fifo; // If the system has multiple CPUs, use FIFO scheduling policy for this process.
441 int lock_pages; // Lock pages into memory.
442 int icmp_rate; // Max number of ICMP unreachable per second to send>
443
444 u32 cluster_address; // Multicast address of cluster.
445 // Send to this address to have everyone hear.
446 char cluster_interface[64]; // Which interface to listen for multicast on.
447 int cluster_iam_master; // Are we the cluster master???
448 int cluster_iam_uptodate; // Set if we've got a full set of state from the master.
449 u32 cluster_master_address; // The network address of the cluster master.
450 // Zero if i am the cluster master.
451 int cluster_seq_number; // Sequence number of the next heartbeat we'll send out
452 // (or the seq number we're next expecting if we're a slave).
453 int cluster_undefined_sessions; // How many sessions we're yet to receive from the master.
454 int cluster_undefined_tunnels; // How many tunnels we're yet to receive from the master.
455 int cluster_highest_sessionid;
456 int cluster_highest_tunnelid;
457 clockt cluster_last_hb; // Last time we saw a heartbeat from the master.
458 int cluster_num_changes; // Number of changes queued.
459
460 int cluster_hb_interval; // How often to send a heartbeat.
461 int cluster_hb_timeout; // How many missed heartbeats trigger an election.
462
463 #ifdef BGP
464 #define BGP_NUM_PEERS 2
465 u16 as_number;
466 struct {
467 char name[64];
468 u16 as;
469 int keepalive;
470 int hold;
471 } neighbour[BGP_NUM_PEERS];
472 #endif
473 };
474
475 enum config_typet { INT, STRING, UNSIGNED_LONG, SHORT, BOOL, IP, MAC };
476 struct config_descriptt
477 {
478 char *key;
479 int offset;
480 int size;
481 enum config_typet type;
482 };
483
484 // arp.c
485 void sendarp(int ifr_idx, const unsigned char* mac, ipt ip);
486
487
488 // ppp.c
489 void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l);
490 void processchap(tunnelidt t, sessionidt s, u8 * p, u16 l);
491 void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l);
492 void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l);
493 void processipin(tunnelidt t, sessionidt s, u8 * p, u16 l);
494 void processccp(tunnelidt t, sessionidt s, u8 * p, u16 l);
495 void sendchap(tunnelidt t, sessionidt s);
496 u8 *makeppp(u8 * b, int size, u8 * p, int l, tunnelidt t, sessionidt s, u16 mtype);
497 void initlcp(tunnelidt t, sessionidt s);
498 void send_ipin(sessionidt s, u8 * buf, int len);
499
500
501 // radius.c
502 void initrad(void);
503 void radiussend(u16 r, u8 state);
504 void processrad(u8 *buf, int len, char socket_index);
505 void radiusretry(u16 r);
506 u16 radiusnew(sessionidt s);
507 void radiusclear(u16 r, sessionidt s);
508
509
510 // l2tpns.c
511 clockt backoff(u8 try);
512 sessionidt sessionbyip(ipt ip);
513 sessionidt sessionbyuser(char *username);
514 void sessionshutdown(sessionidt s, char *reason);
515 void send_garp(ipt ip);
516 void tunnelsend(u8 * buf, u16 l, tunnelidt t);
517 void sendipcp(tunnelidt t, sessionidt s);
518 void processudp(u8 * buf, int len, struct sockaddr_in *addr);
519 void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port);
520 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc);
521 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc);
522 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc);
523
524 #undef LOG
525 #undef LOG_HEX
526 #define LOG(D, a, s, t, f, ...) ({ if (D <= config->debug) _log(D, a, s, t, f, ## __VA_ARGS__); })
527 #define LOG_HEX(D, t, d, s) ({ if (D <= config->debug) _log_hex(D, t, d, s); })
528
529 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...) __attribute__((format (printf, 5, 6)));
530 void _log_hex(int level, const char *title, const char *data, int maxsize);
531
532 int sessionsetup(tunnelidt t, sessionidt s);
533 int run_plugins(int plugin_type, void *data);
534 void rebuild_address_pool(void);
535 void throttle_session(sessionidt s, int rate_in, int rate_out);
536 int load_session(sessionidt, sessiont *);
537 void become_master(void); // We're the master; kick off any required master initializations.
538
539
540 // cli.c
541 void init_cli(char *hostname);
542 void cli_do_file(FILE *fh);
543 void cli_do(int sockfd);
544 int cli_arg_help(struct cli_def *cli, int cr_ok, char *entry, ...);
545
546
547 // icmp.c
548 void host_unreachable(ipt destination, u16 id, ipt source, char *packet, int packet_len);
549
550
551 extern tunnelt *tunnel;
552 extern sessiont *session;
553 extern sessioncountt *sess_count;
554 extern ippoolt *ip_address_pool;
555 #define sessionfree (session[0].next)
556
557 #define log_backtrace(count, max) \
558 if (count++ < max) { \
559 void *array[20]; \
560 char **strings; \
561 int size, i; \
562 LOG(0, 0, 0, t, "Backtrace follows"); \
563 size = backtrace(array, 10); \
564 strings = backtrace_symbols(array, size); \
565 if (strings) for (i = 0; i < size; i++) \
566 { \
567 LOG(0, 0, 0, t, "%s\n", strings[i]); \
568 } \
569 free(strings); \
570 }
571
572
573 extern struct configt *config;
574 extern time_t basetime; // Time when this process started.
575 extern time_t time_now; // Seconds since EPOCH.
576 extern u32 last_id;
577 extern struct Tstats *_statistics;
578 extern ipt my_address;
579 extern int tun_write(u8 *data, int size);
580 extern int clifd;
581
582
583 #define TIME (config->current_time)
584
585 // macros for handling help in cli commands
586 #define CLI_HELP_REQUESTED (argc > 0 && argv[argc-1][strlen(argv[argc-1])-1] == '?')
587 #define CLI_HELP_NO_ARGS (argc > 1 || argv[0][1]) ? CLI_OK : cli_arg_help(cli, 1, NULL)
588
589 // CVS identifiers (for "show version file")
590 extern char const *cvs_id_arp;
591 extern char const *cvs_id_cli;
592 extern char const *cvs_id_cluster;
593 extern char const *cvs_id_constants;
594 extern char const *cvs_id_control;
595 extern char const *cvs_id_icmp;
596 extern char const *cvs_id_l2tpns;
597 extern char const *cvs_id_ll;
598 extern char const *cvs_id_md5;
599 extern char const *cvs_id_ppp;
600 extern char const *cvs_id_radius;
601 extern char const *cvs_id_tbf;
602 extern char const *cvs_id_util;
603
604 #endif /* __L2TPNS_H__ */