/*      $OpenBSD: lcp.h,v 1.8 2024/08/09 05:16:13 deraadt Exp $ */

/*
 * lcp.h - Link Control Protocol 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.
 */

/*
 * Options.
 */
#define CI_MRU          1       /* Maximum Receive Unit */
#define CI_ASYNCMAP     2       /* Async Control Character Map */
#define CI_AUTHTYPE     3       /* Authentication Type */
#define CI_QUALITY      4       /* Quality Protocol */
#define CI_MAGICNUMBER  5       /* Magic Number */
#define CI_PCOMPRESSION 7       /* Protocol Field Compression */
#define CI_ACCOMPRESSION 8      /* Address/Control Field Compression */
#define CI_CALLBACK     13      /* callback */

/*
 * LCP-specific packet types.
 */
#define PROTREJ         8       /* Protocol Reject */
#define ECHOREQ         9       /* Echo Request */
#define ECHOREP         10      /* Echo Reply */
#define DISCREQ         11      /* Discard Request */
#define CBCP_OPT        6       /* Use callback control protocol */

/*
 * The state of options is described by an lcp_options structure.
 */
typedef struct lcp_options {
    u_int passive : 1;          /* Don't die if we don't get a response */
    u_int silent : 1;           /* Wait for the other end to start first */
    u_int restart : 1;          /* Restart vs. exit after close */
    u_int neg_mru : 1;          /* Negotiate the MRU? */
    u_int neg_asyncmap : 1;     /* Negotiate the async map? */
    u_int neg_upap : 1;         /* Ask for UPAP authentication? */
    u_int neg_chap : 1;         /* Ask for CHAP authentication? */
    u_int neg_magicnumber : 1;  /* Ask for magic number? */
    u_int neg_pcompression : 1; /* HDLC Protocol Field Compression? */
    u_int neg_accompression : 1; /* HDLC Address/Control Field Compression? */
    u_int neg_lqr : 1;          /* Negotiate use of Link Quality Reports */
    u_int neg_cbcp : 1;         /* Negotiate use of CBCP */
    u_short mru;                /* Value of MRU */
    u_char chap_mdtype;         /* which MD type (hashing algorithm) */
    u_int32_t asyncmap;         /* Value of async map */
    u_int32_t magicnumber;
    int numloops;               /* Number of loops during magic number neg. */
    u_int32_t lqr_period;       /* Reporting period for LQR 1/100ths second */
} lcp_options;

extern fsm lcp_fsm[];
extern lcp_options lcp_wantoptions[];
extern lcp_options lcp_gotoptions[];
extern lcp_options lcp_allowoptions[];
extern lcp_options lcp_hisoptions[];
extern u_int32_t xmit_accm[][8];

#define DEFMRU  1500            /* Try for this */
#define MINMRU  128             /* No MRUs below this */
#define MAXMRU  16384           /* Normally limit MRU to this */

void lcp_open(int);
void lcp_close(int, char *);
void lcp_lowerup(int);
void lcp_lowerdown(int);
void lcp_sprotrej(int, u_char *, int);  /* send protocol reject */

extern struct protent lcp_protent;

/* Default number of times we receive our magic number from the peer
   before deciding the link is looped-back. */
#define DEFLOOPBACKFAIL 10