release/src/router/xl2tpd/l2tp.h

   1 /*
   2  * Layer Two Tunnelling Protocol Daemon
   3  * Copyright (C) 1998 Adtran, Inc.
   4  * Copyright (C) 2002 Jeff McAdams
   5  *
   6  * Mark Spencer
   7  *
   8  * This software is distributed under the terms
   9  * of the GPL, which you should have received
  10  * along with this source.
  11  *
  12  * Protocol and implementation information,
  13  * structures and constants.
  14  */
  15 /*
  16 typedef unsigned short _u16;
  17 typedef unsigned long long _u64;
  18  */
  19 #ifndef _L2TP_H
  20 #define _L2TP_H
  21
  22 #define MAXSTRLEN 120           /* Maximum length of common strings */
  23
  24 #include <netinet/in.h>
  25 #include <termios.h>
  26 #ifdef OPENBSD
  27 # include <util.h>
  28 #endif
  29 #include "osport.h"
  30 #include "scheduler.h"
  31 #include "misc.h"
  32 #include "file.h"
  33 #include "call.h"
  34 #include "avp.h"
  35 #include "control.h"
  36 #include "aaa.h"
  37 #include "common.h"
  38 #include "ipsecmast.h"
  39
  40 #define CONTROL_PIPE "/var/run/xl2tpd/l2tp-control"
  41
  42 #define BINARY "xl2tpd"
  43 #define SERVER_VERSION "xl2tpd-1.2.6"
  44 #define VENDOR_NAME "xelerance.com"
  45 #ifndef PPPD
  46 #define PPPD            "/usr/sbin/pppd"
  47 #endif
  48 #define CALL_PPP_OPTS "defaultroute"
  49 #define FIRMWARE_REV    0x0690  /* Revision of our firmware (software, in this case) */
  50
  51 #define HELLO_DELAY 60          /* How often to send a Hello message */
  52
  53 struct control_hdr
  54 {
  55     _u16 ver;                   /* Version and more */
  56     _u16 length;                /* Length field */
  57     _u16 tid;                   /* Tunnel ID */
  58     _u16 cid;                   /* Call ID */
  59     _u16 Ns;                    /* Next sent */
  60     _u16 Nr;                    /* Next received */
  61 } __attribute__((packed));
  62
  63 #define CTBIT(ver) (ver & 0x8000)       /* Determins if control or not */
  64 #define CLBIT(ver) (ver & 0x4000)       /* Length bit present.  Must be 1
  65                                            for control messages */
  66
  67 #define CZBITS(ver) (ver &0x37F8)       /* Reserved bits:  We must drop
  68                                            anything with these there */
  69
  70 #define CFBIT(ver) (ver & 0x0800)       /* Presence of Ns and Nr fields
  71                                            flow bit? */
  72
  73 #define CVER(ver) (ver & 0x0007)        /* Version of encapsulation */
  74
  75
  76 struct payload_hdr
  77 {
  78     _u16 ver;                   /* Version and friends */
  79     _u16 length;                /* Optional Length */
  80     _u16 tid;                   /* Tunnel ID */
  81     _u16 cid;                   /* Caller ID */
  82     _u16 Ns;                    /* Optional next sent */
  83     _u16 Nr;                    /* Optional next received */
  84     _u16 o_size;                /* Optional offset size */
  85     _u16 o_pad;                 /* Optional offset padding */
  86 } __attribute__((packed));
  87
  88 #define NZL_TIMEOUT_DIVISOR 4   /* Divide TIMEOUT by this and
  89                                    you know how often to send
  90                                    a zero byte packet */
  91
  92 #define PAYLOAD_BUF 10          /* Provide 10 expansion bytes
  93                                    so we can "decompress" the
  94                                    payloads and simplify coding */
  95 #if 1
  96 #define DEFAULT_MAX_RETRIES 5    /* Recommended value from spec */
  97 #else
  98 #define DEFAULT_MAX_RETRIES 95   /* give us more time to debug */
  99 #endif
 100
 101 #define DEFAULT_RWS_SIZE   4    /* Default max outstanding
 102                                    control packets in queue */
 103 #define DEFAULT_TX_BPS          10000000        /* For outgoing calls, report this speed */
 104 #define DEFAULT_RX_BPS          10000000
 105 #define DEFAULT_MAX_BPS         10000000        /* jz: outgoing calls max bps */
 106 #define DEFAULT_MIN_BPS         10000   /* jz: outgoing calls min bps */
 107 #define PAYLOAD_FUDGE           2       /* How many packets we're willing to drop */
 108 #define MIN_PAYLOAD_HDR_LEN 6
 109
 110 #define UDP_LISTEN_PORT  1701
 111                                 /* FIXME: MAX_RECV_SIZE, what is it? */
 112 #define MAX_RECV_SIZE 4096      /* Biggest packet we'll accept */
 113
 114 #define OUR_L2TP_VERSION 0x100  /* We support version 1, revision 0 */
 115
 116 #define PTBIT(ver) CTBIT(ver)   /* Type bit:  Must be zero for us */
 117 #define PLBIT(ver) CLBIT(ver)   /* Length specified? */
 118 #define PFBIT(ver) CFBIT(ver)   /* Flow control specified? */
 119 #define PVER(ver) CVER(ver)     /* Version */
 120 #define PZBITS(ver) (ver & 0x14F8)      /* Reserved bits */
 121 #define PRBIT(ver) (ver & 0x2000)       /* Reset Sr bit */
 122 #define PSBIT(ver) (ver & 0x0200)       /* Offset size bit */
 123 #define PPBIT(ver) (ver & 0x0100)       /* Preference bit */
 124
 125 struct tunnel
 126 {
 127     struct call *call_head;     /* Member calls */
 128     struct tunnel *next;        /* Allows us to be linked easily */
 129
 130     int fc;                     /* Framing capabilities of peer */
 131     struct schedule_entry *hello;
 132     int ourfc;                  /* Our framing capabilities */
 133     int bc;                     /* Peer's bearer channels */
 134     int hbit;                   /* Allow hidden AVP's? */
 135     int ourbc;                  /* Our bearer channels */
 136     _u64 tb;                    /* Their tie breaker */
 137     _u64 ourtb;                 /* Our tie breaker */
 138     int tid;                    /* Peer's tunnel identifier */
 139     IPsecSAref_t refme;         /* IPsec SA particulars */
 140     IPsecSAref_t refhim;
 141     int ourtid;                 /* Our tunnel identifier */
 142     int qtid;                   /* TID for disconnection */
 143     int firmware;               /* Peer's firmware revision */
 144 #if 0
 145     unsigned int addr;          /* Remote address */
 146     unsigned short port;        /* Port on remote end */
 147 #else
 148     struct sockaddr_in peer;    /* Peer's Address */
 149 #endif
 150     int debug;                  /* Are we debugging or not? */
 151     int nego;                   /* Show Negotiation? */
 152     int count;                  /* How many membmer calls? */
 153     int state;                  /* State of tunnel */
 154     _u16 control_seq_num;       /* Sequence for next packet */
 155     _u16 control_rec_seq_num;   /* Next expected to receive */
 156     int cLr;                    /* Last packet received by peer */
 157     char hostname[MAXSTRLEN];   /* Remote hostname */
 158     char vendor[MAXSTRLEN];     /* Vendor of remote product */
 159     struct challenge chal_us;   /* Their Challenge to us */
 160     struct challenge chal_them; /* Our challenge to them */
 161     char secret[MAXSTRLEN];     /* Secret to use */
 162 #ifdef SANITY
 163     int sanity;                 /* check for sanity? */
 164 #endif
 165     int rws;                    /* Peer's Receive Window Size */
 166     int ourrws;                 /* Receive Window Size */
 167     int rxspeed;                /* Receive bps */
 168     int txspeed;                /* Transmit bps */
 169     struct call *self;
 170     struct lns *lns;            /* LNS that owns us */
 171     struct lac *lac;            /* LAC that owns us */
 172 };
 173
 174 struct tunnel_list
 175 {
 176     struct tunnel *head;
 177     int count;
 178     int calls;
 179 };
 180
 181 /* Values for version */
 182 #define VER_L2TP 2
 183 #define VER_PPTP 3
 184
 185 /* Some PPP sync<->async stuff */
 186 #define fcstab  ppp_crc16_table
 187
 188 #define PPP_FLAG 0x7e
 189 #define PPP_ESCAPE 0x7d
 190 #define PPP_TRANS 0x20
 191
 192 #define PPP_INITFCS 0xffff
 193 #define PPP_GOODFCS 0xf0b8
 194 #define PPP_FCS(fcs,c) (((fcs) >> 8) ^ fcstab[((fcs) ^ (c)) & 0xff])
 195
 196 /* Values for Randomness sources */
 197 #define RAND_DEV 0x0
 198 #define RAND_SYS 0x1
 199 #define RAND_EGD 0x2
 200
 201
 202 /* Error Values */
 203
 204 extern struct tunnel_list tunnels;
 205 extern void tunnel_close (struct tunnel *t);
 206 extern void network_thread ();
 207 extern int init_network ();
 208 extern int kernel_support;
 209 extern int server_socket;
 210 extern struct tunnel *new_tunnel ();
 211 extern struct packet_queue xmit_udp;
 212 extern void destroy_tunnel (struct tunnel *);
 213 extern struct buffer *new_payload (struct sockaddr_in);
 214 extern void recycle_payload (struct buffer *, struct sockaddr_in);
 215 extern void add_payload_hdr (struct tunnel *, struct call *, struct buffer *);
 216 extern int read_packet (struct buffer *, int, int);
 217 extern void udp_xmit (struct buffer *buf, struct tunnel *t);
 218 extern void control_xmit (void *);
 219 extern int ppd;
 220 extern int switch_io;           /* jz */
 221 extern int control_fd;
 222 extern int start_pppd (struct call *c, struct ppp_opts *);
 223 extern void magic_lac_dial (void *);
 224 extern int get_entropy (unsigned char *, int);
 225
 226 #ifndef MIN
 227 #define MIN(a,b) (((a)<(b)) ? (a) : (b))
 228 #endif
 229 #endif
 230
 231
 232 /*
 233  * This is just some stuff to take
 234  * care of kernel definitions
 235  */
 236
 237 #ifdef USE_KERNEL
 238 #include <net/if.h>
 239 #include <linux/if_ether.h>
 240 #include <linux/if_pppox.h>
 241 #include <linux/if_pppol2tp.h>
 242 #endif