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/* $OpenBSD: fsm.h,v 1.5 2002/07/01 19:31:37 deraadt Exp $ */
/*
* fsm.h - {Link, IP} Control Protocol Finite State Machine definitions.
*
* Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The name "Carnegie Mellon University" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For permission or any legal
* details, please contact
* Office of Technology Transfer
* Carnegie Mellon University
* 5000 Forbes Avenue
* Pittsburgh, PA 15213-3890
* (412) 268-4387, fax: (412) 268-7395
* tech-transfer@andrew.cmu.edu
*
* 4. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by Computing Services
* at Carnegie Mellon University (http://www.cmu.edu/computing/)."
*
* CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* Packet header = Code, id, length.
*/
#define HEADERLEN (sizeof (u_char) + sizeof (u_char) + sizeof (u_short))
/*
* CP (LCP, IPCP, etc.) codes.
*/
#define CONFREQ 1 /* Configuration Request */
#define CONFACK 2 /* Configuration Ack */
#define CONFNAK 3 /* Configuration Nak */
#define CONFREJ 4 /* Configuration Reject */
#define TERMREQ 5 /* Termination Request */
#define TERMACK 6 /* Termination Ack */
#define CODEREJ 7 /* Code Reject */
/*
* Each FSM is described by an fsm structure and fsm callbacks.
*/
typedef struct fsm {
int unit; /* Interface unit number */
int protocol; /* Data Link Layer Protocol field value */
int state; /* State */
int flags; /* Contains option bits */
u_char id; /* Current id */
u_char reqid; /* Current request id */
u_char seen_ack; /* Have received valid Ack/Nak/Rej to Req */
int timeouttime; /* Timeout time in milliseconds */
int maxconfreqtransmits; /* Maximum Configure-Request transmissions */
int retransmits; /* Number of retransmissions left */
int maxtermtransmits; /* Maximum Terminate-Request transmissions */
int nakloops; /* Number of nak loops since last ack */
int maxnakloops; /* Maximum number of nak loops tolerated */
struct fsm_callbacks *callbacks; /* Callback routines */
char *term_reason; /* Reason for closing protocol */
int term_reason_len; /* Length of term_reason */
} fsm;
typedef struct fsm_callbacks {
void (*resetci) /* Reset our Configuration Information */
(fsm *);
int (*cilen) /* Length of our Configuration Information */
(fsm *);
void (*addci) /* Add our Configuration Information */
(fsm *, u_char *, int *);
int (*ackci) /* ACK our Configuration Information */
(fsm *, u_char *, int);
int (*nakci) /* NAK our Configuration Information */
(fsm *, u_char *, int);
int (*rejci) /* Reject our Configuration Information */
(fsm *, u_char *, int);
int (*reqci) /* Request peer's Configuration Information */
(fsm *, u_char *, int *, int);
void (*up) /* Called when fsm reaches OPENED state */
(fsm *);
void (*down) /* Called when fsm leaves OPENED state */
(fsm *);
void (*starting) /* Called when we want the lower layer */
(fsm *);
void (*finished) /* Called when we don't want the lower layer */
(fsm *);
void (*protreject) /* Called when Protocol-Reject received */
(int);
void (*retransmit) /* Retransmission is necessary */
(fsm *);
int (*extcode) /* Called when unknown code received */
(fsm *, int, int, u_char *, int);
char *proto_name; /* String name for protocol (for messages) */
} fsm_callbacks;
/*
* Link states.
*/
#define INITIAL 0 /* Down, hasn't been opened */
#define STARTING 1 /* Down, been opened */
#define CLOSED 2 /* Up, hasn't been opened */
#define STOPPED 3 /* Open, waiting for down event */
#define CLOSING 4 /* Terminating the connection, not open */
#define STOPPING 5 /* Terminating, but open */
#define REQSENT 6 /* We've sent a Config Request */
#define ACKRCVD 7 /* We've received a Config Ack */
#define ACKSENT 8 /* We've sent a Config Ack */
#define OPENED 9 /* Connection available */
/*
* Flags - indicate options controlling FSM operation
*/
#define OPT_PASSIVE 1 /* Don't die if we don't get a response */
#define OPT_RESTART 2 /* Treat 2nd OPEN as DOWN, UP */
#define OPT_SILENT 4 /* Wait for peer to speak first */
/*
* Timeouts.
*/
#define DEFTIMEOUT 3 /* Timeout time in seconds */
#define DEFMAXTERMREQS 2 /* Maximum Terminate-Request transmissions */
#define DEFMAXCONFREQS 10 /* Maximum Configure-Request transmissions */
#define DEFMAXNAKLOOPS 5 /* Maximum number of nak loops */
/*
* Prototypes
*/
void fsm_init(fsm *);
void fsm_lowerup(fsm *);
void fsm_lowerdown(fsm *);
void fsm_open(fsm *);
void fsm_close(fsm *, char *);
void fsm_input(fsm *, u_char *, int);
void fsm_protreject(fsm *);
void fsm_sdata(fsm *, int, int, u_char *, int);
/*
* Variables
*/
extern int peer_mru[]; /* currently negotiated peer MRU (per unit) */
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