usr.sbin/pppd/fsm.h

   1 /*
   2  * fsm.h - {Link, IP} Control Protocol Finite State Machine definitions.
   3  *
   4  * Copyright (c) 1989 Carnegie Mellon University.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms are permitted
   8  * provided that the above copyright notice and this paragraph are
   9  * duplicated in all such forms and that any documentation,
  10  * advertising materials, and other materials related to such
  11  * distribution and use acknowledge that the software was developed
  12  * by Carnegie Mellon University.  The name of the
  13  * University may not be used to endorse or promote products derived
  14  * from this software without specific prior written permission.
  15  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  17  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  18  *
  19  * $FreeBSD$
  20  */
  21
  22 /*
  23  * Packet header = Code, id, length.
  24  */
  25 #define HEADERLEN       (sizeof (u_char) + sizeof (u_char) + sizeof (u_short))
  26
  27
  28 /*
  29  *  CP (LCP, IPCP, etc.) codes.
  30  */
  31 #define CONFREQ         1       /* Configuration Request */
  32 #define CONFACK         2       /* Configuration Ack */
  33 #define CONFNAK         3       /* Configuration Nak */
  34 #define CONFREJ         4       /* Configuration Reject */
  35 #define TERMREQ         5       /* Termination Request */
  36 #define TERMACK         6       /* Termination Ack */
  37 #define CODEREJ         7       /* Code Reject */
  38
  39
  40 /*
  41  * Each FSM is described by an fsm structure and fsm callbacks.
  42  */
  43 typedef struct fsm {
  44     int unit;                   /* Interface unit number */
  45     int protocol;               /* Data Link Layer Protocol field value */
  46     int state;                  /* State */
  47     int flags;                  /* Contains option bits */
  48     u_char id;                  /* Current id */
  49     u_char reqid;               /* Current request id */
  50     u_char seen_ack;            /* Have received valid Ack/Nak/Rej to Req */
  51     int timeouttime;            /* Timeout time in milliseconds */
  52     int maxconfreqtransmits;    /* Maximum Configure-Request transmissions */
  53     int retransmits;            /* Number of retransmissions left */
  54     int maxtermtransmits;       /* Maximum Terminate-Request transmissions */
  55     int nakloops;               /* Number of nak loops since last ack */
  56     int maxnakloops;            /* Maximum number of nak loops tolerated */
  57     struct fsm_callbacks *callbacks;    /* Callback routines */
  58     char *term_reason;          /* Reason for closing protocol */
  59     int term_reason_len;        /* Length of term_reason */
  60 } fsm;
  61
  62
  63 typedef struct fsm_callbacks {
  64     void (*resetci)             /* Reset our Configuration Information */
  65                 (fsm *);
  66     int  (*cilen)               /* Length of our Configuration Information */
  67                 (fsm *);
  68     void (*addci)               /* Add our Configuration Information */
  69                 (fsm *, u_char *, int *);
  70     int  (*ackci)               /* ACK our Configuration Information */
  71                 (fsm *, u_char *, int);
  72     int  (*nakci)               /* NAK our Configuration Information */
  73                 (fsm *, u_char *, int);
  74     int  (*rejci)               /* Reject our Configuration Information */
  75                 (fsm *, u_char *, int);
  76     int  (*reqci)               /* Request peer's Configuration Information */
  77                 (fsm *, u_char *, int *, int);
  78     void (*up)                  /* Called when fsm reaches OPENED state */
  79                 (fsm *);
  80     void (*down)                /* Called when fsm leaves OPENED state */
  81                 (fsm *);
  82     void (*starting)            /* Called when we want the lower layer */
  83                 (fsm *);
  84     void (*finished)            /* Called when we don't want the lower layer */
  85                 (fsm *);
  86     void (*protreject)          /* Called when Protocol-Reject received */
  87                 (int);
  88     void (*retransmit)          /* Retransmission is necessary */
  89                 (fsm *);
  90     int  (*extcode)             /* Called when unknown code received */
  91                 (fsm *, int, int, u_char *, int);
  92     char *proto_name;           /* String name for protocol (for messages) */
  93 } fsm_callbacks;
  94
  95
  96 /*
  97  * Link states.
  98  */
  99 #define INITIAL         0       /* Down, hasn't been opened */
 100 #define STARTING        1       /* Down, been opened */
 101 #define CLOSED          2       /* Up, hasn't been opened */
 102 #define STOPPED         3       /* Open, waiting for down event */
 103 #define CLOSING         4       /* Terminating the connection, not open */
 104 #define STOPPING        5       /* Terminating, but open */
 105 #define REQSENT         6       /* We've sent a Config Request */
 106 #define ACKRCVD         7       /* We've received a Config Ack */
 107 #define ACKSENT         8       /* We've sent a Config Ack */
 108 #define OPENED          9       /* Connection available */
 109
 110
 111 /*
 112  * Flags - indicate options controlling FSM operation
 113  */
 114 #define OPT_PASSIVE     1       /* Don't die if we don't get a response */
 115 #define OPT_RESTART     2       /* Treat 2nd OPEN as DOWN, UP */
 116 #define OPT_SILENT      4       /* Wait for peer to speak first */
 117
 118
 119 /*
 120  * Timeouts.
 121  */
 122 #define DEFTIMEOUT      3       /* Timeout time in seconds */
 123 #define DEFMAXTERMREQS  2       /* Maximum Terminate-Request transmissions */
 124 #define DEFMAXCONFREQS  10      /* Maximum Configure-Request transmissions */
 125 #define DEFMAXNAKLOOPS  5       /* Maximum number of nak loops */
 126
 127
 128 /*
 129  * Prototypes
 130  */
 131 void fsm_init(fsm *);
 132 void fsm_lowerup(fsm *);
 133 void fsm_lowerdown(fsm *);
 134 void fsm_open(fsm *);
 135 void fsm_close(fsm *, char *);
 136 void fsm_input(fsm *, u_char *, int);
 137 void fsm_protreject(fsm *);
 138 void fsm_sdata(fsm *, int, int, u_char *, int);
 139
 140
 141 /*
 142  * Variables
 143  */
 144 extern int peer_mru[];          /* currently negotiated peer MRU (per unit) */