minix/lib/liblwip/dist/src/include/netif/ppp/fsm.h

   1 /*
   2  * fsm.h - {Link, IP} Control Protocol Finite State Machine definitions.
   3  *
   4  * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  *
  18  * 3. The name "Carnegie Mellon University" must not be used to
  19  *    endorse or promote products derived from this software without
  20  *    prior written permission. For permission or any legal
  21  *    details, please contact
  22  *      Office of Technology Transfer
  23  *      Carnegie Mellon University
  24  *      5000 Forbes Avenue
  25  *      Pittsburgh, PA  15213-3890
  26  *      (412) 268-4387, fax: (412) 268-7395
  27  *      tech-transfer@andrew.cmu.edu
  28  *
  29  * 4. Redistributions of any form whatsoever must retain the following
  30  *    acknowledgment:
  31  *    "This product includes software developed by Computing Services
  32  *     at Carnegie Mellon University (http://www.cmu.edu/computing/)."
  33  *
  34  * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
  35  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  36  * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
  37  * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  38  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
  39  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  40  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  41  *
  42  * $Id: fsm.h,v 1.10 2004/11/13 02:28:15 paulus Exp $
  43  */
  44
  45 #include "netif/ppp/ppp_opts.h"
  46 #if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
  47
  48 #ifndef FSM_H
  49 #define FSM_H
  50
  51 #include "ppp.h"
  52
  53 /*
  54  * Packet header = Code, id, length.
  55  */
  56 #define HEADERLEN       4
  57
  58
  59 /*
  60  *  CP (LCP, IPCP, etc.) codes.
  61  */
  62 #define CONFREQ         1       /* Configuration Request */
  63 #define CONFACK         2       /* Configuration Ack */
  64 #define CONFNAK         3       /* Configuration Nak */
  65 #define CONFREJ         4       /* Configuration Reject */
  66 #define TERMREQ         5       /* Termination Request */
  67 #define TERMACK         6       /* Termination Ack */
  68 #define CODEREJ         7       /* Code Reject */
  69
  70
  71 /*
  72  * Each FSM is described by an fsm structure and fsm callbacks.
  73  */
  74 typedef struct fsm {
  75     ppp_pcb *pcb;               /* PPP Interface */
  76     const struct fsm_callbacks *callbacks;      /* Callback routines */
  77     const char *term_reason;    /* Reason for closing protocol */
  78     u8_t seen_ack;              /* Have received valid Ack/Nak/Rej to Req */
  79                                   /* -- This is our only flag, we might use u_int :1 if we have more flags */
  80     u16_t protocol;             /* Data Link Layer Protocol field value */
  81     u8_t state;                 /* State */
  82     u8_t flags;                 /* Contains option bits */
  83     u8_t id;                    /* Current id */
  84     u8_t reqid;                 /* Current request id */
  85     u8_t retransmits;           /* Number of retransmissions left */
  86     u8_t nakloops;              /* Number of nak loops since last ack */
  87     u8_t rnakloops;             /* Number of naks received */
  88     u8_t maxnakloops;           /* Maximum number of nak loops tolerated
  89                                    (necessary because IPCP require a custom large max nak loops value) */
  90     u8_t term_reason_len;       /* Length of term_reason */
  91 } fsm;
  92
  93
  94 typedef struct fsm_callbacks {
  95     void (*resetci)             /* Reset our Configuration Information */
  96                 (fsm *);
  97     int  (*cilen)               /* Length of our Configuration Information */
  98                 (fsm *);
  99     void (*addci)               /* Add our Configuration Information */
 100                 (fsm *, u_char *, int *);
 101     int  (*ackci)               /* ACK our Configuration Information */
 102                 (fsm *, u_char *, int);
 103     int  (*nakci)               /* NAK our Configuration Information */
 104                 (fsm *, u_char *, int, int);
 105     int  (*rejci)               /* Reject our Configuration Information */
 106                 (fsm *, u_char *, int);
 107     int  (*reqci)               /* Request peer's Configuration Information */
 108                 (fsm *, u_char *, int *, int);
 109     void (*up)                  /* Called when fsm reaches PPP_FSM_OPENED state */
 110                 (fsm *);
 111     void (*down)                /* Called when fsm leaves PPP_FSM_OPENED state */
 112                 (fsm *);
 113     void (*starting)            /* Called when we want the lower layer */
 114                 (fsm *);
 115     void (*finished)            /* Called when we don't want the lower layer */
 116                 (fsm *);
 117     void (*protreject)          /* Called when Protocol-Reject received */
 118                 (int);
 119     void (*retransmit)          /* Retransmission is necessary */
 120                 (fsm *);
 121     int  (*extcode)             /* Called when unknown code received */
 122                 (fsm *, int, int, u_char *, int);
 123     const char *proto_name;     /* String name for protocol (for messages) */
 124 } fsm_callbacks;
 125
 126
 127 /*
 128  * Link states.
 129  */
 130 #define PPP_FSM_INITIAL         0       /* Down, hasn't been opened */
 131 #define PPP_FSM_STARTING        1       /* Down, been opened */
 132 #define PPP_FSM_CLOSED          2       /* Up, hasn't been opened */
 133 #define PPP_FSM_STOPPED         3       /* Open, waiting for down event */
 134 #define PPP_FSM_CLOSING         4       /* Terminating the connection, not open */
 135 #define PPP_FSM_STOPPING        5       /* Terminating, but open */
 136 #define PPP_FSM_REQSENT         6       /* We've sent a Config Request */
 137 #define PPP_FSM_ACKRCVD         7       /* We've received a Config Ack */
 138 #define PPP_FSM_ACKSENT         8       /* We've sent a Config Ack */
 139 #define PPP_FSM_OPENED          9       /* Connection available */
 140
 141
 142 /*
 143  * Flags - indicate options controlling FSM operation
 144  */
 145 #define OPT_PASSIVE     1       /* Don't die if we don't get a response */
 146 #define OPT_RESTART     2       /* Treat 2nd OPEN as DOWN, UP */
 147 #define OPT_SILENT      4       /* Wait for peer to speak first */
 148
 149
 150 /*
 151  * Timeouts.
 152  */
 153 #if 0 /* moved to ppp_opts.h */
 154 #define DEFTIMEOUT      3       /* Timeout time in seconds */
 155 #define DEFMAXTERMREQS  2       /* Maximum Terminate-Request transmissions */
 156 #define DEFMAXCONFREQS  10      /* Maximum Configure-Request transmissions */
 157 #define DEFMAXNAKLOOPS  5       /* Maximum number of nak loops */
 158 #endif /* moved to ppp_opts.h */
 159
 160
 161 /*
 162  * Prototypes
 163  */
 164 void fsm_init(fsm *f);
 165 void fsm_lowerup(fsm *f);
 166 void fsm_lowerdown(fsm *f);
 167 void fsm_open(fsm *f);
 168 void fsm_close(fsm *f, const char *reason);
 169 void fsm_input(fsm *f, u_char *inpacket, int l);
 170 void fsm_protreject(fsm *f);
 171 void fsm_sdata(fsm *f, u_char code, u_char id, const u_char *data, int datalen);
 172
 173
 174 #endif /* FSM_H */
 175 #endif /* PPP_SUPPORT */