l2tpns.h

   1 // L2TPNS Global Stuff
   2 // $Id: l2tpns.h,v 1.121 2009-12-08 14:49:28 bodea Exp $
   3
   4 #ifndef __L2TPNS_H__
   5 #define __L2TPNS_H__
   6
   7 #include <netinet/in.h>
   8 #include <stdio.h>
   9 #include <signal.h>
  10 #include <stdlib.h>
  11 #include <netinet/in.h>
  12 #include <net/ethernet.h>
  13 #include <sys/socket.h>
  14 #include <arpa/inet.h>
  15 #include <sys/types.h>
  16 #include <libcli.h>
  17
  18 #define VERSION "2.2.1"
  19
  20 // Limits
  21 #define MAXTUNNEL       500             // could be up to 65535
  22 #define MAXBUNDLE       300             // could be up to 65535
  23 #define MAXBUNDLESES    12              // Maximum number of member links in bundle
  24 #define MAXADDRESS      20              // Maximum length for the Endpoint Discrminiator address
  25 #define MAXSESSION      60000           // could be up to 65535
  26 #define MAXTBFS         6000            // Maximum token bucket filters. Might need up to 2 * session.
  27
  28 // Tunnel Id reserved for pppoe
  29 #define TUNNEL_ID_PPPOE 1
  30
  31 #define RADIUS_SHIFT    6
  32 #define RADIUS_FDS      (1 << RADIUS_SHIFT)
  33 #define RADIUS_MASK     ((1 << RADIUS_SHIFT) - 1)
  34 #define MAXRADIUS       (1 << (8 + RADIUS_SHIFT))
  35
  36 #define T_UNDEF         (0xffff)        // A tunnel ID that won't ever be used. Mark session as undefined.
  37 #define T_FREE          (0)             // A tunnel ID that won't ever be used. Mark session as free.
  38
  39 #define MAXCONTROL      1000            // max length control message we ever send...
  40 #define MINMTU          576             // minimum recommended MTU (rfc1063)
  41 #define MAXMTU          2600            // arbitrary maximum MTU
  42 #define PPPoE_MRU       1492            // maximum PPPoE MRU (rfc2516: 1500 less PPPoE header (6) and PPP protocol ID (2))
  43 #define MAXETHER        (MAXMTU+18)     // max packet we try sending to tun
  44 #define MAXTEL          96              // telephone number
  45 #define MAXHOSTNAME     256             // hostname
  46 #define MAXUSER         128             // username
  47 #define MAXPASS         128             // password
  48 #define MAXCLASS        128             // radius class attribute size
  49 #define MAXPLUGINS      20              // maximum number of plugins to load
  50 #define MAXRADSERVER    10              // max radius servers
  51 #define MAXROUTE        10              // max static routes per session
  52 #define MAXIPPOOL       131072          // max number of ip addresses in pool
  53 #define RINGBUFFER_SIZE 10000           // Number of ringbuffer entries to allocate
  54 #define MAX_LOG_LENGTH  512             // Maximum size of log message
  55 #define ECHO_TIMEOUT    10              // Time between last packet sent and LCP ECHO generation
  56 #define IDLE_ECHO_TIMEOUT       240             // Time between last packet seen and session shutdown
  57 #define BUSY_WAIT_TIME  3000            // 5 minutes in 1/10th seconds to wait for radius to cleanup on shutdown
  58
  59 #define MP_BEGIN        0x80            // This value is used when (b)egin bit is set in MP header
  60 #define MP_END          0x40            // This value is used when (e)nd bit is set in MP header
  61 #define MP_BOTH_BITS    0xC0            // This value is used when both bits (begin and end) are set in MP header
  62
  63 #define MINFRAGLEN      64              // Minumum fragment length
  64 #define MAXFRAGLEN      1496    // Maximum length for Multilink fragment (The multilink may contain only one link)
  65 #define MAXFRAGNUM      512             // Maximum number of Multilink fragment in a bundle (must be in the form of 2^X)
  66                                         // it's not expected to have a space for more than 10 unassembled packets = 10 * MAXBUNDLESES
  67 #define MAXFRAGNUM_MASK 511             // Must be equal to MAXFRAGNUM-1
  68
  69 // Constants
  70 #ifndef ETCDIR
  71 #define ETCDIR          "/etc/l2tpns"
  72 #endif
  73
  74 #ifndef LIBDIR
  75 #define LIBDIR          "/usr/lib/l2tpns"
  76 #endif
  77
  78 #ifndef PLUGINDIR
  79 #define PLUGINDIR       LIBDIR          // Plugins
  80 #endif
  81
  82 #ifndef PLUGINCONF
  83 #define PLUGINCONF      ETCDIR          // Plugin config dir
  84 #endif
  85
  86 #ifndef FLASHDIR
  87 #define FLASHDIR        ETCDIR
  88 #endif
  89
  90 #define TUNDEVICE       "/dev/net/tun"
  91 #define RANDOMDEVICE    "/dev/urandom"                  // default, not as secure as /dev/random but non-blocking
  92 #define CONFIGFILE      FLASHDIR "/startup-config"      // Configuration file
  93 #define CLIUSERS        FLASHDIR "/users"               // CLI Users file
  94 #define IPPOOLFILE      FLASHDIR "/ip_pool"             // Address pool configuration
  95 #define ACCT_TIME       3000                            // 5 minute accounting interval
  96 #define ACCT_SHUT_TIME  600                             // 1 minute for counters of shutdown sessions
  97 #define L2TPPORT        1701                            // L2TP port
  98 #define RADPORT         1645                            // old radius port...
  99 #define DAEPORT         3799                            // DAE port
 100 #define PKTARP          0x0806                          // ARP packet type
 101 #define PKTIP           0x0800                          // IPv4 packet type
 102 #define PKTIPV6         0x86DD                          // IPv6 packet type
 103 #define PPPPAP          0xC023
 104 #define PPPCHAP         0xC223
 105 #define PPPLCP          0xC021
 106 #define PPPIPCP         0x8021
 107 #define PPPIPV6CP       0x8057
 108 #define PPPCCP          0x80FD
 109 #define PPPIP           0x0021
 110 #define PPPIPV6         0x0057
 111 #define PPPMP           0x003D
 112 #define MIN_IP_SIZE     0x19
 113
 114 enum {
 115         ConfigReq = 1,
 116         ConfigAck,
 117         ConfigNak,
 118         ConfigRej,
 119         TerminateReq,
 120         TerminateAck,
 121         CodeRej,
 122         ProtocolRej,
 123         EchoReq,
 124         EchoReply,
 125         DiscardRequest,
 126         IdentRequest
 127 };
 128
 129 enum {
 130         AccessRequest = 1,
 131         AccessAccept,
 132         AccessReject,
 133         AccountingRequest,
 134         AccountingResponse,
 135         AccessChallenge = 11,
 136         DisconnectRequest = 40,
 137         DisconnectACK,
 138         DisconnectNAK,
 139         CoARequest,
 140         CoAACK,
 141         CoANAK
 142 };
 143
 144 // PPP phases
 145 enum {
 146         Dead,
 147         Establish,
 148         Authenticate,
 149         Network,
 150         Terminate
 151 };
 152
 153 // PPP states
 154 enum {
 155         Initial,
 156         Starting,
 157         Closed,
 158         Stopped,
 159         Closing,
 160         Stopping,
 161         RequestSent,
 162         AckReceived,
 163         AckSent,
 164         Opened
 165 };
 166
 167 // reset state machine counters
 168 #define initialise_restart_count(_s, _fsm)                      \
 169         sess_local[_s]._fsm.conf_sent =                         \
 170         sess_local[_s]._fsm.nak_sent = 0
 171
 172 // no more attempts
 173 #define zero_restart_count(_s, _fsm) ({                         \
 174         sess_local[_s]._fsm.conf_sent =                         \
 175                 config->ppp_max_configure;                      \
 176         sess_local[_s]._fsm.restart =                           \
 177                 time_now + config->ppp_restart_time;            \
 178 })
 179
 180 // increment ConfReq counter and reset timer
 181 #define restart_timer(_s, _fsm) ({                              \
 182         sess_local[_s]._fsm.conf_sent++;                        \
 183         sess_local[_s]._fsm.restart =                           \
 184                 time_now + config->ppp_restart_time;            \
 185 })
 186
 187 // stop timer on change to state where timer does not run
 188 #define change_state(_s, _fsm, _new) ({                         \
 189         if (_new != session[_s].ppp._fsm)                       \
 190         {                                                       \
 191                 switch (_new)                                   \
 192                 {                                               \
 193                 case Initial:                                   \
 194                 case Starting:                                  \
 195                 case Closed:                                    \
 196                 case Stopped:                                   \
 197                 case Opened:                                    \
 198                         sess_local[_s]._fsm.restart = 0;        \
 199                         initialise_restart_count(_s, _fsm);     \
 200                 }                                               \
 201                 session[_s].ppp._fsm = _new;                    \
 202                 cluster_send_session(_s);                       \
 203         }                                                       \
 204 })
 205
 206 // Types
 207 typedef uint16_t sessionidt;
 208 typedef uint16_t bundleidt;
 209 typedef uint16_t tunnelidt;
 210 typedef uint32_t clockt;
 211 typedef uint8_t hasht[16];
 212
 213 // CLI actions
 214 struct cli_session_actions {
 215         char action;
 216         in_addr_t snoop_ip;
 217         uint16_t snoop_port;
 218         int throttle_in;
 219         int throttle_out;
 220         int filter_in;
 221         int filter_out;
 222 };
 223
 224 #define CLI_SESS_KILL           0x01
 225 #define CLI_SESS_SNOOP          0x02
 226 #define CLI_SESS_NOSNOOP        0x04
 227 #define CLI_SESS_THROTTLE       0x08
 228 #define CLI_SESS_NOTHROTTLE     0x10
 229 #define CLI_SESS_FILTER         0x20
 230 #define CLI_SESS_NOFILTER       0x40
 231
 232 struct cli_tunnel_actions {
 233         char action;
 234 };
 235
 236 #define CLI_TUN_KILL            0x01
 237
 238 // structures
 239 typedef struct                  // route
 240 {
 241         in_addr_t ip;
 242         int prefixlen;
 243 }
 244 routet;
 245
 246 typedef struct controls         // control message
 247 {
 248         struct controls *next;  // next in queue
 249         uint16_t length;        // length
 250         union {
 251                 uint8_t buf[MAXCONTROL];
 252                 uint16_t buf16[MAXCONTROL/2];
 253         } __attribute__ ((__transparent_union__));
 254 }
 255 controlt;
 256
 257 typedef struct {
 258         uint8_t length;                 // Endpoint Discriminator length
 259         uint8_t addr_class;             // Endpoint Discriminator class
 260         uint8_t address[MAXADDRESS];    // Endpoint Discriminator address
 261 } epdist;
 262
 263 typedef struct {
 264         sessionidt sid;                 // Fragment originating session
 265         tunnelidt tid;                  // Fragment originating tunnel
 266         uint8_t flags;                  // MP frame flags
 267         uint32_t seq;                   // fragment seq num
 268         uint32_t jitteravg;
 269         uint16_t length;                // Fragment length
 270         uint8_t data[MAXFRAGLEN];       // Fragment data
 271 } fragmentt;
 272
 273 typedef struct
 274 {
 275         sessionidt next;                // next session in linked list
 276         sessionidt far;                 // far end session ID
 277         tunnelidt tunnel;               // near end tunnel ID
 278         uint8_t flags;                  // session flags: see SESSION_*
 279         struct {
 280                 uint8_t phase;          // PPP phase
 281                 uint8_t lcp:4;          //   LCP    state
 282                 uint8_t ipcp:4;         //   IPCP   state
 283                 uint8_t ipv6cp:4;       //   IPV6CP state
 284                 uint8_t ccp:4;          //   CCP    state
 285         } ppp;
 286         uint16_t mru;                   // maximum receive unit
 287         in_addr_t ip;                   // IP of session set by RADIUS response (host byte order).
 288         int ip_pool_index;              // index to IP pool
 289         uint32_t unique_id;             // unique session id
 290         uint32_t magic;                 // ppp magic number
 291         uint32_t pin, pout;             // packet counts
 292         uint32_t cin, cout;             // byte counts
 293         uint32_t cin_wrap, cout_wrap;   // byte counter wrap count (RADIUS accounting giagawords)
 294         uint32_t cin_delta, cout_delta; // byte count changes (for dump_session())
 295         uint16_t throttle_in;           // upstream throttle rate (kbps)
 296         uint16_t throttle_out;          // downstream throttle rate
 297         uint8_t filter_in;              // input filter index (to ip_filters[N-1]; 0 if none)
 298         uint8_t filter_out;             // output filter index
 299         uint16_t snoop_port;            // Interception destination port
 300         in_addr_t snoop_ip;             // Interception destination IP
 301         clockt opened;                  // when started
 302         clockt die;                     // being closed, when to finally free
 303         uint32_t session_timeout;       // Maximum session time in seconds
 304         uint32_t idle_timeout;          // Maximum idle time in seconds
 305         time_t last_packet;             // Last packet from the user (used for idle timeouts)
 306         time_t last_data;               // Last data packet to/from the user (used for idle timeouts)
 307         in_addr_t dns1, dns2;           // DNS servers
 308         routet route[MAXROUTE];         // static routes
 309         uint16_t tbf_in;                // filter bucket for throttling in from the user.
 310         uint16_t tbf_out;               // filter bucket for throttling out to the user.
 311         int random_vector_length;
 312         uint8_t random_vector[MAXTEL];
 313         char user[MAXUSER];             // user (needed in session for radius stop messages)
 314         char called[MAXTEL];            // called number
 315         char calling[MAXTEL];           // calling number
 316         uint32_t tx_connect_speed;
 317         uint32_t rx_connect_speed;
 318         clockt timeout;                 // Session timeout
 319         uint32_t mrru;                  // Multilink Max-Receive-Reconstructed-Unit
 320         epdist epdis;                   // Multilink Endpoint Discriminator
 321         bundleidt bundle;               // Multilink Bundle Identifier
 322         uint8_t mssf;                   // Multilink Short Sequence Number Header Format
 323         uint8_t walled_garden;          // is this session gardened?
 324         uint8_t classlen;               // class (needed for radius accounting messages)
 325         char class[MAXCLASS];
 326         uint8_t ipv6prefixlen;          // IPv6 route prefix length
 327         struct in6_addr ipv6route;      // Static IPv6 route
 328 #ifdef LAC
 329         sessionidt forwardtosession;    // LNS id_session to forward
 330         uint8_t src_hwaddr[ETH_ALEN];   // MAC addr source (for pppoe sessions 6 bytes)
 331         char reserved[4];               // Space to expand structure without changing HB_VERSION
 332 #else
 333         uint8_t src_hwaddr[ETH_ALEN];   // MAC addr source (for pppoe sessions 6 bytes)
 334         char reserved[6];               // Space to expand structure without changing HB_VERSION
 335 #endif
 336 }
 337 sessiont;
 338
 339 typedef struct
 340 {
 341         int state;                              // current state (bundlestate enum)
 342         uint32_t seq_num_t;                     // Sequence Number (transmission)
 343         uint32_t timeout;                       // Session-Timeout for bundle
 344         uint32_t max_seq;                       // Max value of sequence number field
 345         uint8_t num_of_links;                   // Number of links joint to this bundle
 346         uint32_t online_time;                   // The time this bundle is online
 347         clockt last_check;                      // Last time the timeout is checked
 348         uint32_t mrru;                          // Multilink Max-Receive-Reconstructed-Unit
 349         uint8_t mssf;                           // Multilink Short Sequence Number Header Format
 350         epdist epdis;                           // Multilink Endpoint Discriminator
 351         char user[MAXUSER];                     // Needed for matching member links
 352         sessionidt current_ses;                 // Current session to use for sending (used in RR load-balancing)
 353         sessionidt members[MAXBUNDLESES];       // Array for member links sessions
 354 }
 355 bundlet;
 356
 357 typedef struct
 358 {
 359         fragmentt fragment[MAXFRAGNUM];
 360         uint8_t reassembled_frame[MAXETHER];    // The reassembled frame
 361         uint16_t re_frame_len;                  // The reassembled frame length
 362         uint16_t re_frame_begin_index, re_frame_end_index;      // reassembled frame begin index, end index respectively
 363         uint16_t start_index, end_index;        // start and end sequence numbers available on the fragments array respectively
 364         uint32_t M;                             // Minumum frame sequence number received over all bundle members
 365         uint32_t start_seq;                     // Last received frame sequence number (bearing B bit)
 366 }
 367 fragmentationt;
 368
 369 #define AUTHPAP         1       // allow PAP
 370 #define AUTHCHAP        2       // allow CHAP
 371
 372 typedef struct
 373 {
 374         // packet counters
 375         uint32_t pin;
 376         uint32_t pout;
 377
 378         // byte counters
 379         uint32_t cin;
 380         uint32_t cout;
 381
 382         // PPP restart timer/counters
 383         struct {
 384                 time_t restart;
 385                 int conf_sent;
 386                 int nak_sent;
 387         } lcp, ipcp, ipv6cp, ccp;
 388
 389         // identifier for Protocol-Reject, Code-Reject
 390         uint8_t lcp_ident;
 391
 392         // authentication to use
 393         int lcp_authtype;
 394
 395         // our MRU
 396         uint16_t ppp_mru;
 397
 398         // our MRRU
 399         uint16_t mp_mrru;
 400
 401         // our mssf
 402         uint16_t mp_mssf;
 403
 404         // our Endpoint Discriminator
 405         in_addr_t mp_epdis;
 406
 407         // DoS prevention
 408         clockt last_packet_out;
 409         uint32_t packets_out;
 410         uint32_t packets_dropped;
 411
 412         // RADIUS session in use
 413         uint16_t radius;
 414
 415         // interim RADIUS
 416         time_t last_interim;
 417
 418         // last LCP Echo
 419         time_t last_echo;
 420
 421         // Last Multilink frame sequence number received
 422         uint32_t last_seq;
 423
 424         // jitter average of the session
 425         uint32_t jitteravg;
 426         // time in milliseconds of the last fragment.
 427         uint64_t prev_time;
 428 } sessionlocalt;
 429
 430 // session flags
 431 #define SESSION_PFC     (1 << 0)        // use Protocol-Field-Compression
 432 #define SESSION_ACFC    (1 << 1)        // use Address-and-Control-Field-Compression
 433 #define SESSION_STARTED (1 << 2)        // RADIUS Start record sent
 434
 435 // 328 bytes per tunnel
 436 typedef struct
 437 {
 438         tunnelidt far;          // far end tunnel ID
 439         in_addr_t ip;           // Ip for far end
 440         uint16_t port;          // port for far end
 441         uint16_t window;        // Rx window
 442         uint16_t nr;            // next receive
 443         uint16_t ns;            // next send
 444         int state;              // current state (tunnelstate enum)
 445         clockt last;            // when last control message sent (used for resend timeout)
 446         clockt retry;           // when to try resending pending control
 447         clockt die;             // being closed, when to finally free
 448         clockt lastrec;         // when the last control message was received
 449         char hostname[128];     // tunnel hostname
 450         char vendor[128];       // LAC vendor
 451         uint8_t try;            // number of retrys on a control message
 452         uint16_t controlc;      // outstaind messages in queue
 453         controlt *controls;     // oldest message
 454         controlt *controle;     // newest message
 455 #ifdef LAC
 456         uint16_t isremotelns;   // != 0 if the tunnel is to remote LNS (== index on the conf remote lns)
 457         char reserved[14];              // Space to expand structure without changing HB_VERSION
 458 #else
 459         char reserved[16];              // Space to expand structure without changing HB_VERSION
 460 #endif
 461 }
 462 tunnelt;
 463
 464 // 164 bytes per radius session
 465 typedef struct                  // outstanding RADIUS requests
 466 {
 467         sessionidt session;     // which session this applies to
 468         hasht auth;             // request authenticator
 469         clockt retry;           // when to try next
 470         char pass[129];         // password
 471         uint8_t id;             // ID for PPP response
 472         uint8_t try;            // which try we are on
 473         uint8_t state;          // state of radius requests
 474         uint8_t chap;           // set if CHAP used (is CHAP identifier)
 475         uint8_t term_cause;     // Stop record: Acct-Terminate-Cause
 476         char const *term_msg;   //   terminate reason
 477 }
 478 radiust;
 479
 480 typedef struct
 481 {
 482         in_addr_t       address;        // Host byte order..
 483         char            assigned;       // 1 if assigned, 0 if free
 484         sessionidt      session;
 485         clockt          last;           // last used
 486         char            user[129];      // user (try to have ip addresses persistent)
 487 }
 488 ippoolt;
 489
 490 #ifdef RINGBUFFER
 491 struct Tringbuffer
 492 {
 493         struct {
 494                 char level;
 495                 sessionidt session;
 496                 tunnelidt tunnel;
 497                 char message[MAX_LOG_LENGTH];
 498         } buffer[RINGBUFFER_SIZE];
 499         int head;
 500         int tail;
 501 };
 502 #endif
 503
 504 /*
 505  * Possible tunnel states
 506  * TUNNELFREE -> TUNNELOPEN -> TUNNELDIE -> TUNNELFREE
 507  */
 508 enum
 509 {
 510         TUNNELFREE,             // Not in use
 511         TUNNELOPEN,             // Active tunnel
 512         TUNNELDIE,              // Currently closing
 513         TUNNELOPENING,          // Busy opening
 514         TUNNELUNDEF,            // Undefined
 515 };
 516
 517 enum
 518 {
 519         BUNDLEFREE,             // Not in use
 520         BUNDLEOPEN,             // Active bundle
 521         BUNDLEUNDEF,            // Undefined
 522 };
 523
 524 enum
 525 {
 526         NULLCLASS = 0,          //End Point Discriminator classes
 527         LOCALADDR,
 528         IPADDR,
 529         IEEEMACADDR,
 530         PPPMAGIC,
 531         PSNDN,
 532 };
 533
 534 enum
 535 {
 536         RADIUSNULL,             // Not in use
 537         RADIUSCHAP,             // sending CHAP down PPP
 538         RADIUSAUTH,             // sending auth to RADIUS server
 539         RADIUSSTART,            // sending start accounting to RADIUS server
 540         RADIUSSTOP,             // sending stop accounting to RADIUS server
 541         RADIUSINTERIM,          // sending interim accounting to RADIUS server
 542         RADIUSWAIT,             // waiting timeout before available, in case delayed replies
 543         RADIUSJUSTAUTH,         // sending auth to RADIUS server, just authentication, no ip assigning
 544 };
 545
 546 struct Tstats
 547 {
 548     time_t      start_time;
 549     time_t      last_reset;
 550
 551     uint32_t    tun_rx_packets;
 552     uint32_t    tun_tx_packets;
 553     uint32_t    tun_rx_bytes;
 554     uint32_t    tun_tx_bytes;
 555     uint32_t    tun_rx_errors;
 556     uint32_t    tun_tx_errors;
 557     uint32_t    tun_rx_dropped;
 558
 559     uint32_t    tunnel_rx_packets;
 560     uint32_t    tunnel_tx_packets;
 561     uint32_t    tunnel_rx_bytes;
 562     uint32_t    tunnel_tx_bytes;
 563     uint32_t    tunnel_rx_errors;
 564     uint32_t    tunnel_tx_errors;
 565
 566     uint32_t    tunnel_retries;
 567     uint32_t    radius_retries;
 568
 569     uint32_t    arp_sent;
 570
 571     uint32_t    packets_snooped;
 572
 573     uint32_t    tunnel_created;
 574     uint32_t    session_created;
 575     uint32_t    tunnel_timeout;
 576     uint32_t    session_timeout;
 577     uint32_t    radius_timeout;
 578     uint32_t    radius_overflow;
 579     uint32_t    tunnel_overflow;
 580     uint32_t    session_overflow;
 581
 582     uint32_t    ip_allocated;
 583     uint32_t    ip_freed;
 584
 585     uint32_t    c_forwarded;
 586     uint32_t    recv_forward;
 587
 588     uint32_t    select_called;
 589     uint32_t    multi_read_used;
 590     uint32_t    multi_read_exceeded;
 591
 592 #ifdef STATISTICS
 593     uint32_t    call_processtun;
 594     uint32_t    call_processipout;
 595     uint32_t    call_processipv6out;
 596     uint32_t    call_processudp;
 597     uint32_t    call_sessionbyip;
 598     uint32_t    call_sessionbyipv6;
 599     uint32_t    call_sessionbyuser;
 600     uint32_t    call_sendarp;
 601     uint32_t    call_sendipcp;
 602     uint32_t    call_sendipv6cp;
 603     uint32_t    call_processipv6cp;
 604     uint32_t    call_tunnelsend;
 605     uint32_t    call_sessionkill;
 606     uint32_t    call_sessionshutdown;
 607     uint32_t    call_tunnelkill;
 608     uint32_t    call_tunnelshutdown;
 609     uint32_t    call_assign_ip_address;
 610     uint32_t    call_free_ip_address;
 611     uint32_t    call_dump_acct_info;
 612     uint32_t    call_sessionsetup;
 613     uint32_t    call_processpap;
 614     uint32_t    call_processchap;
 615     uint32_t    call_processlcp;
 616     uint32_t    call_processipcp;
 617     uint32_t    call_processipin;
 618     uint32_t    call_processipv6in;
 619     uint32_t    call_processccp;
 620     uint32_t    call_sendchap;
 621     uint32_t    call_processrad;
 622     uint32_t    call_radiussend;
 623     uint32_t    call_radiusretry;
 624     uint32_t    call_random_data;
 625 #endif
 626 };
 627
 628 #ifdef STATISTICS
 629
 630 #ifdef STAT_CALLS
 631 #define CSTAT(x)        STAT(call_ ## x)
 632 #else
 633 #define CSTAT(x)
 634 #endif
 635
 636 #define STAT(x)         (_statistics->x++)
 637 #define INC_STAT(x,y)   (_statistics->x += (y))
 638 #define GET_STAT(x)     (_statistics->x)
 639 #define SET_STAT(x, y)  (_statistics->x = (y))
 640 #else
 641 #define CSTAT(x)
 642 #define STAT(x)
 643 #define INC_STAT(x,y)
 644 #define GET_STAT(x)     0
 645 #define SET_STAT(x, y)
 646 #endif
 647
 648 #ifndef IFNAMSIZ
 649 # define IFNAMSIZ 16
 650 #endif
 651
 652 typedef struct
 653 {
 654         int             debug;                          // debugging level
 655         time_t          start_time;                     // time when l2tpns was started
 656         char            bandwidth[256];                 // current bandwidth
 657         char            pid_file[256];                  // file to write PID to on startup
 658         int             wrote_pid;
 659         clockt          current_time;                   // 1/10ths of a second since the process started.
 660                                                         // means that we can only run a given process
 661                                                         // for 13 years without re-starting!
 662
 663         char            config_file[128];
 664         int             reload_config;                  // flag to re-read config (set by cli)
 665         int             multi_read_count;               // amount of packets to read per fd in processing loop
 666
 667         char            tundevicename[IFNAMSIZ];                // tun device name
 668         char            log_filename[128];
 669
 670         char            l2tp_secret[64];                // L2TP shared secret
 671         int             l2tp_mtu;                       // MTU of interface used for L2TP
 672
 673         char            random_device[256];             // random device path, defaults to RANDOMDEVICE
 674
 675         int             ppp_restart_time;               // timeout for PPP restart
 676         int             ppp_max_configure;              // max lcp configure requests to send
 677         int             ppp_max_failure;                // max lcp configure naks to send
 678
 679         char            radiussecret[64];
 680         int             radius_accounting;
 681         int             radius_interim;
 682         in_addr_t       radiusserver[MAXRADSERVER];     // radius servers
 683         uint16_t        radiusport[MAXRADSERVER];       // radius base ports
 684         uint8_t         numradiusservers;               // radius server count
 685
 686         uint16_t        radius_dae_port;                // port for radius DAE
 687         uint16_t        radius_bind_min;                // port range for udp sockets used to send/recv radius packets
 688         uint16_t        radius_bind_max;
 689
 690         char            radius_authtypes_s[32];         // list of valid authentication types (chap, pap) in order of preference
 691         int             radius_authtypes;
 692         int             radius_authprefer;
 693
 694         int             allow_duplicate_users;          // allow multiple logins with the same username
 695         int             kill_timedout_sessions;         // kill authenticated sessions with "session_timeout == 0"
 696
 697         in_addr_t       default_dns1, default_dns2;
 698
 699         unsigned long   rl_rate;                        // default throttle rate
 700         int             num_tbfs;                       // number of throttle buckets
 701
 702         char            accounting_dir[128];
 703         in_addr_t       bind_address;
 704         in_addr_t       peer_address;
 705         int             send_garp;                      // Set to true to garp for vip address on startup
 706
 707         int             dump_speed;
 708         char            plugins[64][MAXPLUGINS];
 709         char            old_plugins[64][MAXPLUGINS];
 710
 711         int             next_tbf;                       // Next HTB id available to use
 712         int             scheduler_fifo;                 // If the system has multiple CPUs, use FIFO scheduling
 713                                                         // policy for this process.
 714         int             lock_pages;                     // Lock pages into memory.
 715         int             icmp_rate;                      // Max number of ICMP unreachable per second to send
 716         int             max_packets;                    // DoS prevention: per session limit of packets/0.1s
 717         char            epdis_addr[20];                 // MP Endpoint Discriminator address
 718
 719         in_addr_t       cluster_address;                // Multicast address of cluster.
 720                                                         // Send to this address to have everyone hear.
 721         char            cluster_interface[64];          // Which interface to listen for multicast on.
 722         int             cluster_iam_master;             // Are we the cluster master???
 723         int             cluster_iam_uptodate;           // Set if we've got a full set of state from the master.
 724         in_addr_t       cluster_master_address;         // The network address of the cluster master.
 725                                                         // Zero if i am the cluster master.
 726         int             cluster_seq_number;             // Sequence number of the next heartbeat we'll send out
 727                                                         // (or the seq number we're next expecting if we're a slave).
 728         int             cluster_undefined_sessions;     // How many sessions we're yet to receive from the master.
 729         int             cluster_undefined_bundles;      // How many bundles we're yet to receive from the master.
 730         int             cluster_undefined_tunnels;      // How many tunnels we're yet to receive from the master.
 731         int             cluster_highest_sessionid;
 732         int             cluster_highest_bundleid;
 733         int             cluster_highest_tunnelid;
 734         clockt          cluster_last_hb;                // Last time we saw a heartbeat from the master.
 735         int             cluster_last_hb_ver;            // Heartbeat version last seen from master
 736         int             cluster_num_changes;            // Number of changes queued.
 737
 738         int             cluster_mcast_ttl;              // TTL for multicast packets
 739         int             cluster_hb_interval;            // How often to send a heartbeat.
 740         int             cluster_hb_timeout;             // How many missed heartbeats trigger an election.
 741         uint64_t        cluster_table_version;          // # state changes processed by cluster
 742
 743         struct in6_addr ipv6_prefix;                    // Our IPv6 network pool.
 744
 745
 746         int             cluster_master_min_adv;         // Master advertises routes while the number of up to date
 747                                                         // slaves is less than this value.
 748         in_addr_t       cli_bind_address;               // bind address for CLI
 749         char            hostname[MAXHOSTNAME];  // hostname (overridden by -h on command line)
 750         // Guest change
 751         char            guest_user[MAXUSER];            // Guest account username
 752
 753 #ifdef BGP
 754 #define BGP_NUM_PEERS   2
 755         uint16_t as_number;
 756         struct {
 757                 char name[64];
 758                 uint16_t as;
 759                 int keepalive;
 760                 int hold;
 761                 struct in_addr update_source;
 762         } neighbour[BGP_NUM_PEERS];
 763         in_addr_t       nexthop_address;
 764         struct in6_addr nexthop6_address;
 765 #endif
 766
 767         int echo_timeout; // Time between last packet sent and LCP ECHO generation
 768         int idle_echo_timeout; // Time between last packet seen and
 769                                                    // Drop sessions who have not responded within IDLE_ECHO_TIMEOUT seconds
 770         in_addr_t iftun_address;
 771 #ifdef LAC
 772         int disable_lac_func;
 773         int auth_tunnel_change_addr_src;
 774         int highest_rlnsid;
 775         uint16_t bind_portremotelns;
 776         in_addr_t bind_address_remotelns;
 777 #endif
 778         char pppoe_if_name[IFNAMSIZ];   // Name pppoe interface to bind
 779         char pppoe_service_name[64];    // pppoe service name
 780         char pppoe_ac_name[64];
 781         uint8_t pppoe_hwaddr[ETH_ALEN]; // MAC addr of interface pppoe to bind
 782 } configt;
 783
 784 enum config_typet { INT, STRING, UNSIGNED_LONG, SHORT, BOOL, IPv4, IPv6 };
 785 typedef struct
 786 {
 787         char *key;
 788         int offset;
 789         int size;
 790         enum config_typet type;
 791 } config_descriptt;
 792
 793 typedef struct
 794 {
 795         uint8_t op;     // operation
 796 #define FILTER_PORT_OP_NONE     0 // all ports match
 797 #define FILTER_PORT_OP_EQ       1
 798 #define FILTER_PORT_OP_NEQ      2
 799 #define FILTER_PORT_OP_GT       3
 800 #define FILTER_PORT_OP_LT       4
 801 #define FILTER_PORT_OP_RANGE    5
 802         uint16_t port;  // port (host byte order)
 803         uint16_t port2; // range
 804 } ip_filter_portt;
 805
 806 typedef struct
 807 {
 808         int action;             // permit/deny
 809 #define FILTER_ACTION_DENY      1
 810 #define FILTER_ACTION_PERMIT    2
 811         uint8_t proto;          // protocol: IPPROTO_* (netinet/in.h)
 812         in_addr_t src_ip;       // source ip (network byte order)
 813         in_addr_t src_wild;
 814         ip_filter_portt src_ports;
 815         in_addr_t dst_ip;       // dest ip
 816         in_addr_t dst_wild;
 817         ip_filter_portt dst_ports;
 818         uint8_t frag;           // apply to non-initial fragments
 819         uint8_t tcp_flag_op;    // match type: any, all, established
 820 #define FILTER_FLAG_OP_ANY      1
 821 #define FILTER_FLAG_OP_ALL      2
 822 #define FILTER_FLAG_OP_EST      3
 823         uint8_t tcp_sflags;     // flags set
 824         uint8_t tcp_cflags;     // flags clear
 825         uint32_t counter;       // match count
 826 } ip_filter_rulet;
 827
 828 #define TCP_FLAG_FIN    0x01
 829 #define TCP_FLAG_SYN    0x02
 830 #define TCP_FLAG_RST    0x04
 831 #define TCP_FLAG_PSH    0x08
 832 #define TCP_FLAG_ACK    0x10
 833 #define TCP_FLAG_URG    0x20
 834
 835 #define MAXFILTER               32
 836 #define MAXFILTER_RULES         32
 837 typedef struct
 838 {
 839         char name[32];          // ACL name
 840         int extended;           // type: 0 = standard, 1 = extended
 841         ip_filter_rulet rules[MAXFILTER_RULES];
 842         int used;               // session ref count
 843 } ip_filtert;
 844
 845 // CDN result/error codes
 846 #define CDN_NONE                        0, 0
 847 #define CDN_TRY_ANOTHER                 2, 7
 848 #define CDN_ADMIN_DISC                  3, 0
 849 #define CDN_UNAVAILABLE                 4, 0
 850
 851 // RADIUS Acct-Terminate-Cause values
 852 #define TERM_USER_REQUEST               1
 853 #define TERM_LOST_CARRIER               2
 854 #define TERM_LOST_SERVICE               3
 855 #define TERM_IDLE_TIMEOUT               4
 856 #define TERM_SESSION_TIMEOUT            5
 857 #define TERM_ADMIN_RESET                6
 858 #define TERM_ADMIN_REBOOT               7
 859 #define TERM_PORT_ERROR                 8
 860 #define TERM_NAS_ERROR                  9
 861 #define TERM_NAS_REQUEST                10
 862 #define TERM_NAS_REBOOT                 11
 863 #define TERM_PORT_UNNEEDED              12
 864 #define TERM_PORT_PREEMPTED             13
 865 #define TERM_PORT_SUSPENDED             14
 866 #define TERM_SERVICE_UNAVAILABLE        15
 867 #define TERM_CALLBACK                   16
 868 #define TERM_USER_ERROR                 17
 869 #define TERM_HOST_REQUEST               18
 870 #define TERM_SUPPLICANT_RESTART         19
 871 #define TERM_REAUTHENTICATION_FAILURE   20
 872 #define TERM_PORT_REINIT                21
 873 #define TERM_PORT_DISABLED              22
 874
 875 // on slaves, alow BGP to withdraw cleanly before exiting
 876 #define QUIT_DELAY      5
 877
 878 // quit actions (master)
 879 #define QUIT_FAILOVER   1 // SIGTERM: exit when all control messages have been acked (for cluster failover)
 880 #define QUIT_SHUTDOWN   2 // SIGQUIT: shutdown sessions/tunnels, reject new connections
 881
 882 // arp.c
 883 void sendarp(int ifr_idx, const unsigned char* mac, in_addr_t ip);
 884
 885
 886 // ppp.c
 887 void processpap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 888 void processchap(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 889 void lcp_open(sessionidt s, tunnelidt t);
 890 void lcp_restart(sessionidt s);
 891 void processlcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 892 void processipcp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 893 void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 894 void processipin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 895 void processmpin(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 896 void processmpframe(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint8_t extra);
 897 void processipv6in(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 898 void processccp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l);
 899 void sendchap(sessionidt s, tunnelidt t);
 900 uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, sessionidt s, tunnelidt t, uint16_t mtype, uint8_t prio, bundleidt bid, uint8_t mp_bits);
 901 void sendlcp(sessionidt s, tunnelidt t);
 902 void send_ipin(sessionidt s, uint8_t *buf, int len);
 903 void sendccp(sessionidt s, tunnelidt t);
 904 void protoreject(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint16_t proto);
 905 int join_bundle(sessionidt s);
 906
 907
 908 // radius.c
 909 void initrad(void);
 910 void radiussend(uint16_t r, uint8_t state);
 911 void processrad(uint8_t *buf, int len, char socket_index);
 912 void radiusretry(uint16_t r);
 913 uint16_t radiusnew(sessionidt s);
 914 void radiusclear(uint16_t r, sessionidt s);
 915 void processdae(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struct in_addr *local);
 916 #ifdef LAC
 917 int rad_tunnel_pwdecode(uint8_t *pl2tpsecret, size_t *pl2tpsecretlen, const char *radiussecret, const uint8_t * auth);
 918 #endif
 919
 920 // l2tpns.c
 921 clockt backoff(uint8_t try);
 922 void send_ipv6_ra(sessionidt s, tunnelidt t, struct in6_addr *ip);
 923 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add);
 924 sessionidt sessionbyip(in_addr_t ip);
 925 sessionidt sessionbyipv6(struct in6_addr ip);
 926 sessionidt sessionbyuser(char *username);
 927 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta);
 928 void random_data(uint8_t *buf, int len);
 929 void sessionkill(sessionidt s, char *reason);
 930 void sessionshutdown(sessionidt s, char const *reason, int cdn_result, int cdn_error, int term_cause);
 931 void filter_session(sessionidt s, int filter_in, int filter_out);
 932 void send_garp(in_addr_t ip);
 933 void tunnelsend(uint8_t *buf, uint16_t l, tunnelidt t);
 934 int tun_write(uint8_t *data, int size);
 935 void adjust_tcp_mss(sessionidt s, tunnelidt t, uint8_t *buf, int len, uint8_t *tcp);
 936 void sendipcp(sessionidt s, tunnelidt t);
 937 void sendipv6cp(sessionidt s, tunnelidt t);
 938 void processudp(uint8_t *buf, int len, struct sockaddr_in *addr);
 939 void processipout(uint8_t *buf, int len);
 940 void snoop_send_packet(uint8_t *packet, uint16_t size, in_addr_t destination, uint16_t port);
 941 int find_filter(char const *name, size_t len);
 942 int ip_filter(uint8_t *buf, int len, uint8_t filter);
 943 int cmd_show_ipcache(struct cli_def *cli, char *command, char **argv, int argc);
 944 int cmd_show_hist_idle(struct cli_def *cli, char *command, char **argv, int argc);
 945 int cmd_show_hist_open(struct cli_def *cli, char *command, char **argv, int argc);
 946 #ifdef LAC
 947 tunnelidt lac_new_tunnel();
 948 void lac_tunnelclear(tunnelidt t);
 949 void lac_send_SCCRQ(tunnelidt t, uint8_t * auth, unsigned int auth_len);
 950 void lac_send_ICRQ(tunnelidt t, sessionidt s);
 951 void lac_tunnelshutdown(tunnelidt t, char *reason, int result, int error, char *msg);
 952 #endif
 953
 954 #undef LOG
 955 #undef LOG_HEX
 956 #define LOG(D, s, t, f, ...)    ({ if (D <= config->debug) _log(D, s, t, f, ## __VA_ARGS__); })
 957 #define LOG_HEX(D, t, d, s)     ({ if (D <= config->debug) _log_hex(D, t, d, s); })
 958
 959 void _log(int level, sessionidt s, tunnelidt t, const char *format, ...) __attribute__((format (printf, 4, 5)));
 960 void _log_hex(int level, const char *title, const uint8_t *data, int maxsize);
 961
 962
 963 int sessionsetup(sessionidt s, tunnelidt t);
 964 int run_plugins(int plugin_type, void *data);
 965 void rebuild_address_pool(void);
 966 void throttle_session(sessionidt s, int rate_in, int rate_out);
 967 int load_session(sessionidt, sessiont *);
 968 void become_master(void);       // We're the master; kick off any required master initializations.
 969
 970
 971 // cli.c
 972 void init_cli();
 973 void cli_init_complete(char *hostname);
 974 void cli_do_file(FILE *fh);
 975 void cli_do(int sockfd);
 976 int cli_arg_help(struct cli_def *cli, int cr_ok, char *entry, ...);
 977
 978
 979 // icmp.c
 980 void host_unreachable(in_addr_t destination, uint16_t id, in_addr_t source, uint8_t *packet, int packet_len);
 981
 982
 983 extern tunnelt *tunnel;
 984 extern bundlet *bundle;
 985 extern sessiont *session;
 986 extern sessionlocalt *sess_local;
 987 extern ippoolt *ip_address_pool;
 988 #define sessionfree (session[0].next)
 989
 990
 991 extern configt *config;
 992 extern time_t basetime;         // Time when this process started.
 993 extern time_t time_now;         // Seconds since EPOCH.
 994 extern char main_quit;
 995 extern uint32_t last_id;
 996 extern struct Tstats *_statistics;
 997 extern in_addr_t my_address;
 998 extern int clifd;
 999 extern int epollfd;
1000
1001 struct event_data {
1002         enum {
1003                 FD_TYPE_CLI,
1004                 FD_TYPE_CLUSTER,
1005                 FD_TYPE_TUN,
1006                 FD_TYPE_UDP,
1007                 FD_TYPE_CONTROL,
1008                 FD_TYPE_DAE,
1009                 FD_TYPE_RADIUS,
1010                 FD_TYPE_BGP,
1011                 FD_TYPE_NETLINK,
1012 #ifdef LAC
1013                 FD_TYPE_UDPLAC,
1014 #endif
1015                 FD_TYPE_PPPOEDISC,
1016                 FD_TYPE_PPPOESESS
1017         } type;
1018         int index; // for RADIUS, BGP
1019 };
1020
1021 #define TIME (config->current_time)
1022
1023 extern uint16_t MRU;
1024 extern uint16_t MSS;
1025
1026 // macros for handling help in cli commands
1027 #define CLI_HELP_REQUESTED      (argc > 0 && argv[argc-1][strlen(argv[argc-1])-1] == '?')
1028 #define CLI_HELP_NO_ARGS        (argc > 1 || argv[0][1]) ? CLI_OK : cli_arg_help(cli, 1, NULL)
1029
1030 #endif /* __L2TPNS_H__ */