l2tpns.h

   1 // L2TPNS Global Stuff
   2 // $Id: l2tpns.h,v 1.24 2004-10-29 04:01:11 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 "2.0.2"
  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_TIMEOUT       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;
 126 };
 127
 128 #define CLI_SESS_KILL           0x01
 129 #define CLI_SESS_SNOOP          0x02
 130 #define CLI_SESS_NOSNOOP        0x04
 131 #define CLI_SESS_THROTTLE       0x08
 132 #define CLI_SESS_NOTHROTTLE     0x10
 133
 134 struct cli_tunnel_actions {
 135         char action;
 136 };
 137
 138 #define CLI_TUN_KILL            0x01
 139
 140 // dump header: update number if internal format changes
 141 #define DUMP_MAGIC "L2TPNS#" VERSION "#"
 142
 143 // structures
 144 typedef struct routes           // route
 145 {
 146         ipt ip;
 147         ipt mask;
 148 }
 149 routet;
 150
 151 typedef struct controls         // control message
 152 {
 153         struct controls *next;  // next in queue
 154         u16 length;             // length
 155         u8 buf[MAXCONTROL];
 156 }
 157 controlt;
 158
 159 typedef struct sessions
 160 {
 161         sessionidt next;                // next session in linked list
 162         sessionidt far;                 // far end session ID
 163         tunnelidt tunnel;               // near end tunnel ID
 164         ipt ip;                         // IP of session set by RADIUS response (host byte order).
 165         int ip_pool_index;              // index to IP pool
 166         unsigned long unique_id;        // unique session id
 167         u16 nr;                         // next receive
 168         u16 ns;                         // next send
 169         u32 magic;                      // ppp magic number
 170         u32 cin, cout;                  // byte counts
 171         u32 pin, pout;                  // packet counts
 172         u32 total_cin;                  // This counter is never reset while a session is open
 173         u32 total_cout;                 // This counter is never reset while a session is open
 174         u32 id;                         // session id
 175         u32 throttle;                   // non-zero if this session is throttled.
 176         clockt opened;                  // when started
 177         clockt die;                     // being closed, when to finally free
 178         time_t last_packet;             // Last packet from the user (used for idle timeouts)
 179         ipt dns1, dns2;                 // DNS servers
 180         routet route[MAXROUTE];         // static routes
 181         u16 radius;                     // which radius session is being used (0 for not waiting on authentication)
 182         u16 mru;                        // maximum receive unit
 183         u16 tbf_in;                     // filter bucket for throttling in from the user.
 184         u16 tbf_out;                    // filter bucket for throttling out to the user.
 185         u8 l2tp_flags;                  // various bit flags from the ICCN on the l2tp tunnel.
 186         u8 reserved_old_snoop;          // No longer used - remove at some time
 187         u8 walled_garden;               // is this session gardened?
 188         u8 flags1;                      // additional flags (currently unused);
 189         char random_vector[MAXTEL];
 190         int random_vector_length;
 191         char user[129];                 // user (needed in seesion for radius stop messages) (can we reduce this? --mo)
 192         char called[MAXTEL];            // called number
 193         char calling[MAXTEL];           // calling number
 194         u32 tx_connect_speed;
 195         u32 rx_connect_speed;
 196         u32 flags;                      // Various session flags.
 197         ipt snoop_ip;                   // Interception destination IP
 198         u16 snoop_port;                 // Interception destination port
 199         u16 sid;                        // near end session id.
 200         char reserved[20];              // Space to expand structure without changing HB_VERSION
 201 }
 202 sessiont;
 203
 204 #define SF_IPCP_ACKED   (1<<0)          // Has this session seen an IPCP Ack?
 205
 206 typedef struct {
 207         u32     cin;
 208         u32     cout;
 209 } sessioncountt;
 210
 211 #define SESSIONPFC      1            // PFC negotiated flags
 212 #define SESSIONACFC     2           // ACFC negotiated flags
 213 #define SESSIONLCPACK   4       // LCP negotiated
 214
 215 // 168 bytes per tunnel
 216 typedef struct tunnels
 217 {
 218         tunnelidt far;          // far end tunnel ID
 219         ipt ip;                 // Ip for far end
 220         portt port;             // port for far end
 221         u16 window;             // Rx window
 222         u16 nr;                 // next receive
 223         u16 ns;                 // next send
 224         int state;              // current state (tunnelstate enum)
 225         clockt last;            // when last control message sent (used for resend timeout)
 226         clockt retry;           // when to try resenting pending control
 227         clockt die;             // being closed, when to finally free
 228         clockt lastrec;         // when the last control message was received
 229         char hostname[128];     // tunnel hostname
 230         char vendor[128];       // LAC vendor
 231         u8 try;                 // number of retrys on a control message
 232         u16 controlc;           // outstaind messages in queue
 233         controlt *controls;     // oldest message
 234         controlt *controle;     // newest message
 235 }
 236 tunnelt;
 237
 238 // 180 bytes per radius session
 239 typedef struct radiuss          // outstanding RADIUS requests
 240 {
 241         sessionidt session;     // which session this applies to
 242         hasht auth;             // request authenticator
 243         clockt retry;           // when to try next
 244         char calling[MAXTEL];   // calling number
 245         char pass[129];         // password
 246         u8 id;                  // ID for PPP response
 247         u8 try;                 // which try we are on
 248         u8 state;               // state of radius requests
 249         u8 chap;                // set if CHAP used (is CHAP identifier)
 250 }
 251 radiust;
 252
 253 typedef struct
 254 {
 255         ipt             address;        // Host byte order..
 256         char            assigned;       // 1 if assigned, 0 if free
 257         sessionidt      session;
 258         clockt          last;           // last used
 259         char            user[129];      // user (try to have ip addresses persistent)
 260 }
 261 ippoolt;
 262
 263 #ifdef RINGBUFFER
 264 struct Tringbuffer
 265 {
 266         struct {
 267                 char level;
 268                 sessionidt session;
 269                 tunnelidt tunnel;
 270                 ipt address;
 271                 char message[MAX_LOG_LENGTH];
 272         } buffer[RINGBUFFER_SIZE];
 273         int head;
 274         int tail;
 275 };
 276 #endif
 277
 278 /*
 279  * Possible tunnel states
 280  * TUNNELFREE -> TUNNELOPEN -> TUNNELDIE -> TUNNELFREE
 281  */
 282 enum
 283 {
 284         TUNNELFREE,             // Not in use
 285         TUNNELOPEN,             // Active tunnel
 286         TUNNELDIE,              // Currently closing
 287         TUNNELOPENING,          // Busy opening
 288         TUNNELUNDEF,            // Undefined
 289 };
 290
 291 enum
 292 {
 293         RADIUSNULL,             // Not in use
 294         RADIUSCHAP,             // sending CHAP down PPP
 295         RADIUSAUTH,             // sending auth to RADIUS server
 296         RADIUSIPCP,             // sending IPCP to end user
 297         RADIUSSTART,            // sending start accounting to RADIUS server
 298         RADIUSSTOP,             // sending stop accounting to RADIUS server
 299         RADIUSWAIT,             // waiting timeout before available, in case delayed replies
 300         RADIUSDEAD,             // errored while talking to radius server.
 301 };
 302
 303 struct Tstats
 304 {
 305     time_t              start_time;
 306     time_t              last_reset;
 307
 308     unsigned long       tun_rx_packets;
 309     unsigned long       tun_tx_packets;
 310     unsigned long       tun_rx_bytes;
 311     unsigned long       tun_tx_bytes;
 312     unsigned long       tun_rx_errors;
 313     unsigned long       tun_tx_errors;
 314
 315     unsigned long       tunnel_rx_packets;
 316     unsigned long       tunnel_tx_packets;
 317     unsigned long       tunnel_rx_bytes;
 318     unsigned long       tunnel_tx_bytes;
 319     unsigned long       tunnel_rx_errors;
 320     unsigned long       tunnel_tx_errors;
 321
 322     unsigned long       tunnel_retries;
 323     unsigned long       radius_retries;
 324
 325     unsigned long       arp_sent;
 326
 327     unsigned long       packets_snooped;
 328
 329     unsigned long       tunnel_created;
 330     unsigned long       session_created;
 331     unsigned long       tunnel_timeout;
 332     unsigned long       session_timeout;
 333     unsigned long       radius_timeout;
 334     unsigned long       radius_overflow;
 335     unsigned long       tunnel_overflow;
 336     unsigned long       session_overflow;
 337
 338     unsigned long       ip_allocated;
 339     unsigned long       ip_freed;
 340
 341     unsigned long       c_forwarded;
 342     unsigned long       recv_forward;
 343 #ifdef STATISTICS
 344     unsigned long       call_processtun;
 345     unsigned long       call_processipout;
 346     unsigned long       call_processudp;
 347     unsigned long       call_sessionbyip;
 348     unsigned long       call_sessionbyuser;
 349     unsigned long       call_sendarp;
 350     unsigned long       call_sendipcp;
 351     unsigned long       call_tunnelsend;
 352     unsigned long       call_sessionkill;
 353     unsigned long       call_sessionshutdown;
 354     unsigned long       call_tunnelkill;
 355     unsigned long       call_tunnelshutdown;
 356     unsigned long       call_assign_ip_address;
 357     unsigned long       call_free_ip_address;
 358     unsigned long       call_dump_acct_info;
 359     unsigned long       call_sessionsetup;
 360     unsigned long       call_processpap;
 361     unsigned long       call_processchap;
 362     unsigned long       call_processlcp;
 363     unsigned long       call_processipcp;
 364     unsigned long       call_processipin;
 365     unsigned long       call_processccp;
 366     unsigned long       call_sendchap;
 367     unsigned long       call_processrad;
 368     unsigned long       call_radiussend;
 369     unsigned long       call_radiusretry;
 370 #endif
 371 };
 372
 373 #ifdef STATISTICS
 374
 375 #ifdef STAT_CALLS
 376 #define CSTAT(x)        STAT(x)
 377 #else
 378 #define CSTAT(x)
 379 #endif
 380
 381 #define STAT(x)         (_statistics->x++)
 382 #define INC_STAT(x,y)   (_statistics->x += (y))
 383 #define GET_STAT(x)     (_statistics->x)
 384 #define SET_STAT(x, y)  (_statistics->x = (y))
 385 #else
 386 #define CSTAT(x)
 387 #define STAT(x)
 388 #define INC_STAT(x,y)
 389 #define GET_STAT(x)     0
 390 #define SET_STAT(x, y)
 391 #endif
 392
 393 struct configt
 394 {
 395         int             debug;                          // debugging level
 396         time_t          start_time;                     // time when l2tpns was started
 397         char            bandwidth[256];                 // current bandwidth
 398         char            pid_file[256];                  // file to write PID to on startup
 399         int             wrote_pid;
 400         clockt          current_time;                   // 1/10ths of a second since the process started.
 401                                                         // means that we can only run a given process
 402                                                         // for 13 years without re-starting!
 403
 404         char            config_file[128];
 405         int             reload_config;                  // flag to re-read config (set by cli)
 406         int             cleanup_interval;               // interval between regular cleanups (in seconds)
 407         int             multi_read_count;               // amount of packets to read per fd in processing loop
 408
 409         char            tundevice[10];                  // tun device name
 410         char            log_filename[128];
 411         char            l2tpsecret[64];
 412
 413         char            radiussecret[64];
 414         int             radius_accounting;
 415         ipt             radiusserver[MAXRADSERVER];     // radius servers
 416         u16             radiusport[MAXRADSERVER];       // radius base ports
 417         u8              numradiusservers;               // radius server count
 418         short           num_radfds;                     // Number of radius filehandles allocated
 419
 420         ipt             default_dns1, default_dns2;
 421
 422         unsigned long   rl_rate;                        // throttle rate
 423         int             num_tbfs;                       // number of throttle buckets
 424
 425         int             save_state;
 426         char            accounting_dir[128];
 427         ipt             bind_address;
 428         int             send_garp;                      // Set to true to garp for vip address on startup
 429
 430         int             target_uid;
 431         int             dump_speed;
 432         char            plugins[64][MAXPLUGINS];
 433         char            old_plugins[64][MAXPLUGINS];
 434
 435         int             next_tbf;                       // Next HTB id available to use
 436         int             scheduler_fifo;                 // If the system has multiple CPUs, use FIFO scheduling policy for this process.
 437         int             lock_pages;                     // Lock pages into memory.
 438         int             icmp_rate;                      // Max number of ICMP unreachable per second to send>
 439
 440         u32             cluster_address;                // Multicast address of cluster.
 441                                                         // Send to this address to have everyone hear.
 442         char            cluster_interface[64];          // Which interface to listen for multicast on.
 443         int             cluster_iam_master;             // Are we the cluster master???
 444         int             cluster_iam_uptodate;           // Set if we've got a full set of state from the master.
 445         u32             cluster_master_address;         // The network address of the cluster master.
 446                                                         // Zero if i am the cluster master.
 447         int             cluster_seq_number;             // Sequence number of the next heartbeat we'll send out
 448                                                         // (or the seq number we're next expecting if we're a slave).
 449         int             cluster_undefined_sessions;     // How many sessions we're yet to receive from the master.
 450         int             cluster_undefined_tunnels;      // How many tunnels we're yet to receive from the master.
 451         int             cluster_highest_sessionid;
 452         int             cluster_highest_tunnelid;
 453         clockt          cluster_last_hb;                // Last time we saw a heartbeat from the master.
 454         int             cluster_num_changes;            // Number of changes queued.
 455
 456         int             cluster_hb_interval;            // How often to send a heartbeat.
 457         int             cluster_hb_timeout;             // How many missed heartbeats trigger an election.
 458
 459 #ifdef BGP
 460         u16             as_number;
 461         char            bgp_peer[2][64];
 462         u16             bgp_peer_as[2];
 463 #endif
 464 };
 465
 466 struct config_descriptt
 467 {
 468         char *key;
 469         int offset;
 470         int size;
 471         enum { INT, STRING, UNSIGNED_LONG, SHORT, BOOL, IP, MAC } type;
 472 };
 473
 474 // arp.c
 475 void sendarp(int ifr_idx, const unsigned char* mac, ipt ip);
 476
 477
 478 // ppp.c
 479 void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l);
 480 void processchap(tunnelidt t, sessionidt s, u8 * p, u16 l);
 481 void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l);
 482 void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l);
 483 void processipin(tunnelidt t, sessionidt s, u8 * p, u16 l);
 484 void processccp(tunnelidt t, sessionidt s, u8 * p, u16 l);
 485 void sendchap(tunnelidt t, sessionidt s);
 486 u8 *makeppp(u8 * b, int size, u8 * p, int l, tunnelidt t, sessionidt s, u16 mtype);
 487 u8 *findppp(u8 * b, u8 mtype);
 488 void initlcp(tunnelidt t, sessionidt s);
 489 void dumplcp(u8 *p, int l);
 490
 491
 492 // radius.c
 493 void initrad(void);
 494 void radiussend(u16 r, u8 state);
 495 void processrad(u8 *buf, int len, char socket_index);
 496 void radiusretry(u16 r);
 497 u16 radiusnew(sessionidt s);
 498 void radiusclear(u16 r, sessionidt s);
 499
 500 // throttle.c
 501 int throttle_session(sessionidt s, int throttle);
 502
 503
 504 // rl.c
 505 void init_rl();
 506 u16 rl_create_tbf();
 507 u16 rl_get_tbf();
 508 void rl_done_tbf(u16 t);
 509 void rl_destroy_tbf(u16 t);
 510
 511
 512 // l2tpns.c
 513 clockt now(void);
 514 clockt backoff(u8 try);
 515 void routeset(sessionidt, ipt ip, ipt mask, ipt gw, u8 add);
 516 void inittun(void);
 517 void initudp(void);
 518 void initdata(int optdebug, char *optconfig);
 519 void initippool();
 520 sessionidt sessionbyip(ipt ip);
 521 sessionidt sessionbyuser(char *username);
 522 void sessionshutdown(sessionidt s, char *reason);
 523 void sessionsendarp(sessionidt s);
 524 void send_garp(ipt ip);
 525 void sessionkill(sessionidt s, char *reason);
 526 void control16(controlt * c, u16 avp, u16 val, u8 m);
 527 void control32(controlt * c, u16 avp, u32 val, u8 m);
 528 void controls(controlt * c, u16 avp, char *val, u8 m);
 529 void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m);
 530 controlt *controlnew(u16 mtype);
 531 void controlnull(tunnelidt t);
 532 void controladd(controlt * c, tunnelidt t, sessionidt s);
 533 void tunnelsend(u8 * buf, u16 l, tunnelidt t);
 534 void tunnelkill(tunnelidt t, char *reason);
 535 void tunnelshutdown(tunnelidt t, char *reason);
 536 void sendipcp(tunnelidt t, sessionidt s);
 537 void processipout(u8 * buf, int len);
 538 void processarp(u8 * buf, int len);
 539 void processudp(u8 * buf, int len, struct sockaddr_in *addr);
 540 void processtun(u8 * buf, int len);
 541 void processcontrol(u8 * buf, int len, struct sockaddr_in *addr);
 542 int assign_ip_address(sessionidt s);
 543 void free_ip_address(sessionidt s);
 544 void snoop_send_packet(char *packet, u16 size, ipt destination, u16 port);
 545 void dump_acct_info();
 546 void mainloop(void);
 547 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc);
 548 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc);
 549 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc);
 550
 551 #define log _log
 552 #ifndef log_hex
 553 #define log_hex(a,b,c,d) do{if (a <= config->debug) _log_hex(a,0,0,0,b,c,d);}while (0)
 554 #endif
 555 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...) __attribute__((format (printf, 5, 6)));
 556 void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *title, const char *data, int maxsize);
 557 void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response);
 558 int sessionsetup(tunnelidt t, sessionidt s);
 559 int cluster_send_session(int s);
 560 int cluster_send_tunnel(int t);
 561 int cluster_send_goodbye();
 562 void init_cli(char *hostname);
 563 void cli_do_file(FILE *fh);
 564 void cli_do(int sockfd);
 565 int cli_arg_help(struct cli_def *cli, int cr_ok, char *entry, ...);
 566 #ifdef RINGBUFFER
 567 void ringbuffer_dump(FILE *stream);
 568 #endif
 569 void initplugins(void);
 570 int run_plugins(int plugin_type, void *data);
 571 void add_plugin(char *plugin_name);
 572 void remove_plugin(char *plugin_name);
 573 void plugins_done(void);
 574 void tunnelclear(tunnelidt t);
 575 void host_unreachable(ipt destination, u16 id, ipt source, char *packet, int packet_len);
 576 void fix_address_pool(int sid);
 577 void rebuild_address_pool(void);
 578 void send_ipin(sessionidt s, u8 * buf, int len);
 579 int throttle_session(sessionidt s, int throttle);
 580 int load_session(sessionidt, sessiont *);
 581 void become_master(void);       // We're the master; kick off any required master initializations.
 582 extern tunnelt *tunnel;
 583 extern sessiont *session;
 584 extern sessioncountt *sess_count;
 585 extern ippoolt *ip_address_pool;
 586 #define sessionfree (session[0].next)
 587
 588 #define log_backtrace(count, max) \
 589 if (count++ < max) { \
 590         void *array[20]; \
 591         char **strings; \
 592         int size, i; \
 593         log(0, 0, 0, t, "Backtrace follows"); \
 594         size = backtrace(array, 10); \
 595         strings = backtrace_symbols(array, size); \
 596         if (strings) for (i = 0; i < size; i++) \
 597         { \
 598                 log(0, 0, 0, t, "%s\n", strings[i]); \
 599         } \
 600         free(strings); \
 601 }
 602
 603
 604 extern struct configt *config;
 605 extern time_t basetime;         // Time when this process started.
 606 extern time_t time_now;         // Seconds since EPOCH.
 607 extern u32 last_id;
 608 extern struct Tstats *_statistics;
 609 extern ipt my_address;
 610 extern int tun_write(u8 *data, int size);
 611
 612
 613 #define TIME (config->current_time)
 614
 615 // macros for handling help in cli commands
 616 #define CLI_HELP_REQUESTED      (argc > 0 && argv[argc-1][strlen(argv[argc-1])-1] == '?')
 617 #define CLI_HELP_NO_ARGS        (argc > 1 || argv[0][1]) ? CLI_OK : cli_arg_help(cli, 1, NULL)
 618
 619 // CVS identifiers (for "show version file")
 620 extern char const *cvs_id_arp;
 621 extern char const *cvs_id_cli;
 622 extern char const *cvs_id_cluster;
 623 extern char const *cvs_id_constants;
 624 extern char const *cvs_id_control;
 625 extern char const *cvs_id_icmp;
 626 extern char const *cvs_id_l2tpns;
 627 extern char const *cvs_id_ll;
 628 extern char const *cvs_id_md5;
 629 extern char const *cvs_id_ppp;
 630 extern char const *cvs_id_radius;
 631 extern char const *cvs_id_tbf;
 632 extern char const *cvs_id_util;
 633
 634 #endif /* __L2TPNS_H__ */