usr.sbin/ppp/fsm.h

   1 /*-
   2  * Copyright (c) 1996 - 2001 Brian Somers <brian@Awfulhak.org>
   3  *          based on work by Toshiharu OHNO <tony-o@iij.ad.jp>
   4  *                           Internet Initiative Japan, Inc (IIJ)
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * $FreeBSD: src/usr.sbin/ppp/fsm.h,v 1.23.2.3 2002/09/01 02:12:27 brian Exp $
  29  * $DragonFly: src/usr.sbin/ppp/fsm.h,v 1.2 2003/06/17 06:30:00 dillon Exp $
  30  */
  31
  32 /*
  33  *  State of machine
  34  */
  35 #define ST_INITIAL      0
  36 #define ST_STARTING     1
  37 #define ST_CLOSED       2
  38 #define ST_STOPPED      3
  39 #define ST_CLOSING      4
  40 #define ST_STOPPING     5
  41 #define ST_REQSENT      6
  42 #define ST_ACKRCVD      7
  43 #define ST_ACKSENT      8
  44 #define ST_OPENED       9
  45
  46 #define ST_MAX          10
  47 #define ST_UNDEF        -1
  48
  49 #define MODE_REQ        0
  50 #define MODE_NAK        1
  51 #define MODE_REJ        2
  52 #define MODE_NOP        3
  53 #define MODE_ACK        4       /* pseudo mode for ccp negotiations */
  54
  55 #define OPEN_PASSIVE    -1
  56
  57 #define FSM_REQ_TIMER   1
  58 #define FSM_TRM_TIMER   2
  59
  60 #define FSM_OPTLEN      100
  61
  62 struct fsm;
  63
  64 struct fsm_retry {
  65   u_int timeout;                             /* FSM retry frequency */
  66   u_int maxreq;                              /* Max Config REQ retries */
  67   u_int maxtrm;                              /* Max Term REQ retries */
  68 };
  69
  70 struct fsm_decode {
  71   u_char ack[FSM_OPTLEN], *ackend;
  72   u_char nak[FSM_OPTLEN], *nakend;
  73   u_char rej[FSM_OPTLEN], *rejend;
  74 };
  75
  76 struct fsm_callbacks {
  77   int (*LayerUp)(struct fsm *);                 /* Layer is now up (tlu) */
  78   void (*LayerDown)(struct fsm *);              /* About to come down (tld) */
  79   void (*LayerStart)(struct fsm *);             /* Layer about to start (tls) */
  80   void (*LayerFinish)(struct fsm *);            /* Layer now down (tlf) */
  81   void (*InitRestartCounter)(struct fsm *, int);/* Set fsm timer load */
  82   void (*SendConfigReq)(struct fsm *);          /* Send REQ please */
  83   void (*SentTerminateReq)(struct fsm *);       /* Term REQ just sent */
  84   void (*SendTerminateAck)(struct fsm *, u_char); /* Send Term ACK please */
  85   void (*DecodeConfig)(struct fsm *, u_char *, u_char *, int,
  86                        struct fsm_decode *);    /* Deal with incoming data */
  87   int (*RecvResetReq)(struct fsm *fp);          /* Reset output */
  88   void (*RecvResetAck)(struct fsm *fp, u_char); /* Reset input */
  89 };
  90
  91 struct fsm_parent {
  92   void (*LayerStart) (void *, struct fsm *);         /* tls */
  93   void (*LayerUp) (void *, struct fsm *);            /* tlu */
  94   void (*LayerDown) (void *, struct fsm *);          /* tld */
  95   void (*LayerFinish) (void *, struct fsm *);        /* tlf */
  96   void *object;
  97 };
  98
  99 struct link;
 100 struct bundle;
 101
 102 struct fsm {
 103   const char *name;             /* Name of protocol */
 104   u_short proto;                /* Protocol number */
 105   u_short min_code;
 106   u_short max_code;
 107   int open_mode;                /* Delay before config REQ (-1 forever) */
 108   int state;                    /* State of the machine */
 109   u_char reqid;                 /* Next request id */
 110   int restart;                  /* Restart counter value */
 111
 112   struct {
 113     int reqs;                   /* Max config REQs before a close() */
 114     int naks;                   /* Max config NAKs before a close() */
 115     int rejs;                   /* Max config REJs before a close() */
 116   } more;
 117
 118   struct pppTimer FsmTimer;     /* Restart Timer */
 119   struct pppTimer OpenTimer;    /* Delay before opening */
 120
 121   /*
 122    * This timer times the ST_STOPPED state out after the given value
 123    * (specified via "set stopped ...").  Although this isn't specified in the
 124    * rfc, the rfc *does* say that "the application may use higher level
 125    * timers to avoid deadlock". The StoppedTimer takes effect when the other
 126    * side ABENDs rather than going into ST_ACKSENT (and sending the ACK),
 127    * causing ppp to time out and drop into ST_STOPPED.  At this point,
 128    * nothing will change this state :-(
 129    */
 130   struct pppTimer StoppedTimer;
 131   int LogLevel;
 132
 133   /* The link layer active with this FSM (may be our bundle below) */
 134   struct link *link;
 135
 136   /* Our high-level link */
 137   struct bundle *bundle;
 138
 139   const struct fsm_parent *parent;
 140   const struct fsm_callbacks *fn;
 141 };
 142
 143 struct fsmheader {
 144   u_char code;                  /* Request code */
 145   u_char id;                    /* Identification */
 146   u_short length;               /* Length of packet */
 147 };
 148
 149 #define CODE_CONFIGREQ  1
 150 #define CODE_CONFIGACK  2
 151 #define CODE_CONFIGNAK  3
 152 #define CODE_CONFIGREJ  4
 153 #define CODE_TERMREQ    5
 154 #define CODE_TERMACK    6
 155 #define CODE_CODEREJ    7
 156 #define CODE_PROTOREJ   8
 157 #define CODE_ECHOREQ    9       /* Used in LCP */
 158 #define CODE_ECHOREP    10      /* Used in LCP */
 159 #define CODE_DISCREQ    11
 160 #define CODE_IDENT      12      /* Used in LCP Extension */
 161 #define CODE_TIMEREM    13      /* Used in LCP Extension */
 162 #define CODE_RESETREQ   14      /* Used in CCP */
 163 #define CODE_RESETACK   15      /* Used in CCP */
 164
 165 struct fsm_opt_hdr {
 166   u_char id;
 167   u_char len;
 168 };
 169
 170 #define MAX_FSM_OPT_LEN 52
 171 struct fsm_opt {
 172   struct fsm_opt_hdr hdr;
 173   u_char data[MAX_FSM_OPT_LEN-2];
 174 };
 175
 176 #define INC_FSM_OPT(ty, length, o)                      \
 177   do {                                                  \
 178     (o)->hdr.id = (ty);                                 \
 179     (o)->hdr.len = (length);                            \
 180     (o) = (struct fsm_opt *)((u_char *)(o) + (length)); \
 181   } while (0)
 182
 183
 184 extern void fsm_Init(struct fsm *, const char *, u_short, int, int, int,
 185                      struct bundle *, struct link *, const  struct fsm_parent *,
 186                      struct fsm_callbacks *, const char * const [3]);
 187 extern void fsm_Output(struct fsm *, u_int, u_int, u_char *, int, int);
 188 extern void fsm_Open(struct fsm *);
 189 extern void fsm_Up(struct fsm *);
 190 extern void fsm_Down(struct fsm *);
 191 extern void fsm_Input(struct fsm *, struct mbuf *);
 192 extern void fsm_Close(struct fsm *);
 193 extern int fsm_NullRecvResetReq(struct fsm *);
 194 extern void fsm_NullRecvResetAck(struct fsm *, u_char);
 195 extern void fsm_Reopen(struct fsm *);
 196 extern void fsm2initial(struct fsm *);
 197 extern const char *State2Nam(u_int);
 198 extern struct fsm_opt *fsm_readopt(u_char **);
 199 extern void fsm_rej(struct fsm_decode *, const struct fsm_opt *);
 200 extern void fsm_ack(struct fsm_decode *, const struct fsm_opt *);
 201 extern void fsm_nak(struct fsm_decode *, const struct fsm_opt *);
 202 extern void fsm_opt_normalise(struct fsm_decode *);