l2tpns.h

   1 // L2TPNS Global Stuff
   2 // $Id: l2tpns.h,v 1.1 2003/12/16 07:07:39 fred_nerk Exp $
   3
   4 #include <netinet/in.h>
   5 #include <stdio.h>
   6
   7 #include "config.h"
   8
   9 #define VERSION "1.0"
  10
  11 // Limits
  12 #define MAXTUNNEL       500             // could be up to 65535
  13 #define MAXSESSION      50000           // could be up to 65535
  14 #define MAXRADIUS       255
  15 #define MAXCONTROL      1000            // max length control message we ever send...
  16 #define MAXETHER        (1500+18)       // max packet we try sending to tap
  17 #define MAXTEL          96              // telephone number
  18 #define MAXRADSERVER    10              // max radius servers
  19 #define MAXROUTE        10              // max static routes per session
  20 #define MAXIPPOOL       131072          // max number of ip addresses in pool
  21 #define RINGBUFFER_SIZE 10000           // Number of ringbuffer entries to allocate
  22 #define MAX_LOG_LENGTH  512             // Maximum size of log message
  23 #define ECHO_TIMEOUT    60              // Time between last packet sent and LCP ECHO generation
  24 #define IDLE_TIMEOUT    240             // Time between last packet sent and LCP ECHO generation
  25
  26 // Constants
  27 #define STATISTICS
  28 #define STAT_CALLS
  29 #define RINGBUFFER
  30 #define UDP             17
  31 #define TAPDEVICE       "/dev/net/tun"
  32 #define CLIUSERS        ETCDIR "l2tpns.users"   // CLI Users file
  33 #define CONFIGFILE      ETCDIR "l2tpns.cfg"     // Configuration file
  34 #define IPPOOLFILE      ETCDIR "l2tpns.ip_pool" // Address pool configuration
  35 #define STATEFILE       "/tmp/l2tpns.dump"      // State dump file
  36
  37 #ifndef LIBDIR
  38 #define LIBDIR          "/usr/lib/l2tpns"
  39 #endif
  40
  41 #define ACCT_TIME       3000            // 5 minute accounting interval
  42 #define L2TPPORT        1701            // L2TP port
  43 #define RADPORT         1645            // old radius port...
  44 #define RADAPORT        1646            // old radius accounting port
  45 #define PKTARP          0x0806          // ARP packet type
  46 #define PKTIP           0x0800          // IP packet type
  47 #define PSEUDOMAC       0x0200          // pseudo MAC prefix (local significant MAC)
  48 #define PPPPAP          0xC023
  49 #define PPPCHAP         0xC223
  50 #define PPPLCP          0xC021
  51 #define PPPIPCP         0x8021
  52 #define PPPCCP          0x80FD
  53 #define PPPIP           0x0021
  54 #define PPPMP           0x003D
  55 #define ConfigReq       1
  56 #define ConfigAck       2
  57 #define ConfigNak       3
  58 #define ConfigRej       4
  59 #define TerminateReq    5
  60 #define TerminateAck    6
  61 #define CodeRej         7
  62 #define ProtocolRej     8
  63 #define EchoReq         9
  64 #define EchoReply       10
  65 #define DiscardRequest  11
  66
  67 #undef TC_TBF
  68 #define TC_HTB
  69
  70 // Types
  71 typedef unsigned short u16;
  72 typedef unsigned int u32;
  73 typedef unsigned char u8;
  74 typedef u32 ipt;
  75 typedef u16 portt;
  76 typedef u16 sessionidt;
  77 typedef u16 tunnelidt;
  78 typedef u32 clockt;
  79 typedef u8 hasht[16];
  80
  81 // structures
  82 typedef struct routes           // route
  83 {
  84         ipt ip;
  85         ipt mask;
  86 }
  87 routet;
  88
  89 typedef struct controls         // control message
  90 {
  91         struct controls *next;       // next in queue
  92         u16 length;             // length
  93         u8 buf[MAXCONTROL];
  94 }
  95 controlt;
  96
  97 typedef struct stbft
  98 {
  99     struct stbft *next;
 100     char handle[10];
 101     char in_use;
 102     int mark;
 103 } tbft;
 104
 105
 106 // 336 bytes per session
 107 typedef struct sessions
 108 {
 109         sessionidt next;             // next session in linked list
 110         sessionidt far;              // far end session ID
 111         tunnelidt tunnel;            // tunnel ID
 112         ipt ip;                 // IP of session set by RADIUS response
 113         unsigned long sid;      // session id for hsddb
 114         u16 nr;                 // next receive
 115         u16 ns;                 // next send
 116         u32 magic;              // ppp magic number
 117         u32 cin, cout;               // byte counts
 118         u32 pin, pout;               // packet counts
 119         u32 id;                 // session id
 120         clockt opened;             // when started
 121         clockt die;                // being closed, when to finally free
 122         time_t last_packet;     // Last packet from the user (used for idle timeouts)
 123         ipt dns1, dns2;               // DNS servers
 124         routet route[MAXROUTE];    // static routes
 125         u8 radius;             // which radius session is being used (0 for not waiting on authentication)
 126         u8 flags;              // various bit flags
 127         u8 snoop;               // are we snooping this session?
 128         u8 throttle;            // is this session throttled?
 129         u8 walled_garden;       // is this session stuck in the walled garden?
 130         u16 mru;                // maximum receive unit
 131         u16 tbf;                // filter bucket for throttling
 132         char random_vector[MAXTEL];
 133         int random_vector_length;
 134         char user[129];          // user (needed in seesion for radius stop messages)
 135         char called[MAXTEL];     // called number
 136         char calling[MAXTEL];     // calling number
 137         unsigned long tx_connect_speed;
 138         unsigned long rx_connect_speed;
 139 }
 140 sessiont;
 141
 142 #define SESSIONPFC      1            // PFC negotiated flags
 143 #define SESSIONACFC     2           // ACFC negotiated flags
 144
 145 // 168 bytes per tunnel
 146 typedef struct tunnels
 147 {
 148         tunnelidt next;         // next tunnel in linked list
 149         tunnelidt far;          // far end tunnel ID
 150         ipt ip;                 // Ip for far end
 151         portt port;             // port for far end
 152         u16 window;             // Rx window
 153         u16 nr;                 // next receive
 154         u16 ns;                 // next send
 155         clockt last;            // when last control message sent (used for resend timeout)
 156         clockt retry;           // when to try resenting pending control
 157         clockt die;             // being closed, when to finally free
 158         char hostname[128];     // tunnel hostname
 159         char vendor[128];       // LAC vendor
 160         u8 try;                 // number of retrys on a control message
 161         u16 controlc;           // outstaind messages in queue
 162         controlt *controls;     // oldest message
 163         controlt *controle;     // newest message
 164 }
 165 tunnelt;
 166
 167 // 180 bytes per radius session
 168 typedef struct radiuss          // outstanding RADIUS requests
 169 {
 170         u8 next;               // next in free list
 171         sessionidt session;          // which session this applies to
 172         hasht auth;               // request authenticator
 173         clockt retry;              // ehwne to try next
 174         char calling[MAXTEL];    // calling number
 175         char pass[129];          // password
 176         u8 id;                 // ID for PPP response
 177         u8 try;                // which try we are on
 178         u8 state;              // state of radius requests
 179         u8 chap;               // set if CHAP used (is CHAP identifier)
 180 }
 181 radiust;
 182
 183 typedef struct
 184 {
 185         ipt     address;
 186         char    assigned;       // 1 if assigned, 0 if free
 187 }
 188 ippoolt;
 189
 190 #ifdef RINGBUFFER
 191 struct Tringbuffer
 192 {
 193         struct {
 194                 char level;
 195                 sessionidt session;
 196                 tunnelidt tunnel;
 197                 ipt address;
 198                 char message[MAX_LOG_LENGTH];
 199         } buffer[RINGBUFFER_SIZE];
 200         int head;
 201         int tail;
 202 };
 203 #endif
 204
 205 enum
 206 {
 207     RADIUSNULL,                   // Not in use
 208     RADIUSCHAP,                   // sending CHAP down PPP
 209     RADIUSAUTH,                   // sending auth to RADIUS server
 210     RADIUSIPCP,                   // sending IPCP to end user
 211     RADIUSSTART,                  // sending start accounting to RADIUS server
 212     RADIUSSTOP,                   // sending stop accounting to RADIUS server
 213     RADIUSWAIT                   // waiting timeout before available, in case delayed replies
 214 };
 215
 216 struct Tstats
 217 {
 218     time_t              start_time;
 219     time_t              last_reset;
 220
 221     unsigned long       tap_rx_packets;
 222     unsigned long       tap_tx_packets;
 223     unsigned long       tap_rx_bytes;
 224     unsigned long       tap_tx_bytes;
 225     unsigned long       tap_rx_errors;
 226     unsigned long       tap_tx_errors;
 227
 228     unsigned long       tunnel_rx_packets;
 229     unsigned long       tunnel_tx_packets;
 230     unsigned long       tunnel_rx_bytes;
 231     unsigned long       tunnel_tx_bytes;
 232     unsigned long       tunnel_rx_errors;
 233     unsigned long       tunnel_tx_errors;
 234
 235     unsigned long       tunnel_retries;
 236     unsigned long       radius_retries;
 237
 238     unsigned long       arp_errors;
 239     unsigned long       arp_replies;
 240     unsigned long       arp_discarded;
 241     unsigned long       arp_sent;
 242     unsigned long       arp_recv;
 243
 244     unsigned long       packets_snooped;
 245
 246     unsigned long       tunnel_created;
 247     unsigned long       session_created;
 248     unsigned long       tunnel_timeout;
 249     unsigned long       session_timeout;
 250     unsigned long       radius_timeout;
 251     unsigned long       radius_overflow;
 252     unsigned long       tunnel_overflow;
 253     unsigned long       session_overflow;
 254
 255     unsigned long       ip_allocated;
 256     unsigned long       ip_freed;
 257 #ifdef STAT_CALLS
 258     unsigned long       call_processtap;
 259     unsigned long       call_processarp;
 260     unsigned long       call_processipout;
 261     unsigned long       call_processudp;
 262     unsigned long       call_sessionbyip;
 263     unsigned long       call_sessionbyuser;
 264     unsigned long       call_sendarp;
 265     unsigned long       call_sendipcp;
 266     unsigned long       call_tunnelsend;
 267     unsigned long       call_sessionkill;
 268     unsigned long       call_sessionshutdown;
 269     unsigned long       call_tunnelkill;
 270     unsigned long       call_tunnelshutdown;
 271     unsigned long       call_assign_ip_address;
 272     unsigned long       call_free_ip_address;
 273     unsigned long       call_dump_acct_info;
 274     unsigned long       call_sessionsetup;
 275     unsigned long       call_processpap;
 276     unsigned long       call_processchap;
 277     unsigned long       call_processlcp;
 278     unsigned long       call_processipcp;
 279     unsigned long       call_processipin;
 280     unsigned long       call_processccp;
 281     unsigned long       call_sendchap;
 282     unsigned long       call_processrad;
 283     unsigned long       call_radiussend;
 284     unsigned long       call_radiusretry;
 285 #endif
 286 };
 287
 288 #ifdef STATISTICS
 289 #define STAT(x)         _statistics->x++
 290 #define INC_STAT(x,y)   _statistics->x += y
 291 #define GET_STAT(x)     _statistics->x
 292 #define SET_STAT(x, y)  _statistics->x = y
 293 #else
 294 #define STAT(x)
 295 #define INC_STAT(x,y)
 296 #define GET_STAT(x)     0
 297 #define SET_STAT(x, y)
 298 #endif
 299
 300 // arp.c
 301 void sendarp(int ifr_idx, const unsigned char* mac, ipt ip);
 302
 303
 304 // ppp.c
 305 void processpap(tunnelidt t, sessionidt s, u8 * p, u16 l);
 306 void processchap(tunnelidt t, sessionidt s, u8 * p, u16 l);
 307 void processlcp(tunnelidt t, sessionidt s, u8 * p, u16 l);
 308 void processipcp(tunnelidt t, sessionidt s, u8 * p, u16 l);
 309 void processipin(tunnelidt t, sessionidt s, u8 * p, u16 l);
 310 void processccp(tunnelidt t, sessionidt s, u8 * p, u16 l);
 311 void sendchap(tunnelidt t, sessionidt s);
 312 u8 *makeppp(u8 * b, u8 * p, int l, tunnelidt t, sessionidt s, u16 mtype);
 313 u8 *findppp(u8 * b, u8 mtype);
 314 void initlcp(tunnelidt t, sessionidt s);
 315 void dumplcp(char *p, int l);
 316
 317
 318 // radius.c
 319 void initrad(void);
 320 void radiussend(u8 r, u8 state);
 321 void processrad(u8 *buf, int len);
 322 void radiusretry(u8 r);
 323 u8 radiusnew(sessionidt s);
 324
 325 // throttle.c
 326 int throttle_session(sessionidt s, int throttle);
 327
 328
 329 // rl.c
 330 void init_rl();
 331 u16 rl_create_tbf();
 332 u16 rl_get_tbf();
 333 void rl_done_tbf(u16 t);
 334 void rl_destroy_tbf(u16 t);
 335
 336
 337 // l2tpns.c
 338 clockt now(void);
 339 clockt backoff(u8 try);
 340 void routeset(ipt ip, ipt mask, ipt gw, u8 add);
 341 void inittap(void);
 342 void initudp(void);
 343 void initdata(void);
 344 void initippool();
 345 sessionidt sessionbyip(ipt ip);
 346 /* NB - sessionbyuser ignores walled garden'd sessions */
 347 sessionidt sessionbyuser(char *username);
 348 void sessionshutdown(sessionidt s, char *reason);
 349 void sessionsendarp(sessionidt s);
 350 void send_garp(ipt ip);
 351 void sessionkill(sessionidt s, char *reason);
 352 void control16(controlt * c, u16 avp, u16 val, u8 m);
 353 void control32(controlt * c, u16 avp, u32 val, u8 m);
 354 void controls(controlt * c, u16 avp, char *val, u8 m);
 355 void controlb(controlt * c, u16 avp, char *val, unsigned int len, u8 m);
 356 controlt *controlnew(u16 mtype);
 357 void controlnull(tunnelidt t);
 358 void controladd(controlt * c, tunnelidt t, sessionidt s);
 359 void tunnelsend(u8 * buf, u16 l, tunnelidt t);
 360 void tunnelkill(tunnelidt t, char *reason);
 361 void tunnelshutdown(tunnelidt t, char *reason);
 362 void sendipcp(tunnelidt t, sessionidt s);
 363 void processipout(u8 * buf, int len);
 364 void processarp(u8 * buf, int len);
 365 void processudp(u8 * buf, int len, struct sockaddr_in *addr);
 366 void processtap(u8 * buf, int len);
 367 void processcontrol(u8 * buf, int len, struct sockaddr_in *addr);
 368 ipt assign_ip_address();
 369 void free_ip_address(ipt address);
 370 void snoop_send_packet(char *packet, u16 size);
 371 void dump_acct_info();
 372 void mainloop(void);
 373 #define log _log
 374 #ifndef log_hex
 375 #define log_hex(a,b,c,d) do{if (a <= debug) _log_hex(a,0,0,0,b,c,d);}while (0)
 376 #endif
 377 void _log(int level, ipt address, sessionidt s, tunnelidt t, const char *format, ...);
 378 void _log_hex(int level, ipt address, sessionidt s, tunnelidt t, const char *title, const char *data, int maxsize);
 379 void build_chap_response(char *challenge, u8 id, u16 challenge_length, char **challenge_response);
 380 int sessionsetup(tunnelidt t, sessionidt s, u8 routes);
 381 int cluster_send_session(int s);
 382 int cluster_send_tunnel(int t);
 383 #ifdef HAVE_LIBCLI
 384 void init_cli();
 385 void cli_do(int sockfd);
 386 #endif
 387 #ifdef RINGBUFFER
 388 void ringbuffer_dump(FILE *stream);
 389 #endif
 390 void initplugins();
 391 int run_plugins(int plugin_type, void *data);
 392 void add_plugin(char *plugin_name);
 393 void remove_plugin(char *plugin_name);