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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/npppd/npppd/fsm.c	Lines:	0	268	0.0 %
Date:	2017-11-07	Branches:	0	212	0.0 %


/*	$OpenBSD: fsm.c,v 1.9 2017/05/30 17:22:00 yasuoka Exp $ */

/**@file
 * This file was adapted from NetBSD:/usr/src/usr.sbin/pppd/pppd/fsm.c
 */
/*
 * fsm.c is simple and it can be use without modifications.  So keep the
 * original as much as possible.  (2005/04 yasuoka)
 *
 * XXX: I think the same message for initial configure-request is a bad idea
 * XXX: on resending configure-request.(yasuoka)
 */
/*	$NetBSD: fsm.c,v 1.13 2000/09/23 22:39:35 christos Exp $	*/

/*
 * fsm.c - {Link, IP} Control Protocol Finite State Machine.
 *
 * Copyright (c) 1989 Carnegie Mellon University.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by Carnegie Mellon University.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

/*
 * TODO:
 * Randomize fsm id on link/init.
 * Deal with variable outgoing MTU.
 */

#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <stdarg.h>
#include <syslog.h>
#include <stdlib.h>

/* npppd related headers below */
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/if_dl.h>
#include <time.h>
#include <event.h>
#include "debugutil.h"
#include "slist.h"
#include "npppd.h"
#include "fsm.h"

#ifdef	FSM_DEBUG
#define	FSMDEBUG(x)	fsm_log x
#define	FSM_ASSERT(x)	ASSERT(x)
#else
#define	FSMDEBUG(x)
#define	FSM_ASSERT(x)
#endif

#define	HEADERLEN	4

#ifdef RCSID
static const char rcsid[] = RCSID;
#endif

static void fsm_timeout(void *);
static void fsm_rconfreq(fsm *, int, u_char *, int);
static void fsm_rconfack(fsm *, int, u_char *, int);
static void fsm_rconfnakrej(fsm *, int, int, u_char *, int);
static void fsm_rtermreq(fsm *, int, u_char *, int);
static void fsm_rtermack(fsm *);
static void fsm_rcoderej(fsm *, u_char *, int);
static void fsm_sconfreq(fsm *, int);

#define PROTO_NAME(f)	((f)->callbacks->proto_name)

void
fsm_evtimer_timeout(int fd, short evtype, void *ctx)
{
	struct evtimer_wrap *wrap;

	wrap = ctx;
	wrap->func(wrap->ctx);
}


/*
 * fsm_init - Initialize fsm.
 *
 * Initialize fsm state.
 */
void
fsm_init(f)
    fsm *f;
{
    f->state = INITIAL;
    f->flags = 0;
    f->id = 0;				/* XXX Start with random id? */
    f->timeouttime = DEFTIMEOUT;
    f->maxconfreqtransmits = DEFMAXCONFREQS;
    f->maxtermtransmits = DEFMAXTERMREQS;
    f->maxnakloops = DEFMAXNAKLOOPS;
    f->term_reason_len = 0;
    memset(&f->timerctx, 0, sizeof(f->timerctx));
    f->timerctx.ctx = f;
}


/*
 * fsm_lowerup - The lower layer is up.
 */
void
fsm_lowerup(f)
    fsm *f;
{
    switch( f->state ){
    case INITIAL:
	f->state = CLOSED;
	break;

    case STARTING:
	if( f->flags & OPT_SILENT )
	    f->state = STOPPED;
	else {
	    /* Send an initial configure-request */
	    fsm_sconfreq(f, 0);
	    f->state = REQSENT;
	}
	break;

    default:
	FSMDEBUG((f, LOG_DEBUG, "Up event in state %d!", f->state));
    }
}


/*
 * fsm_lowerdown - The lower layer is down.
 *
 * Cancel all timeouts and inform upper layers.
 */
void
fsm_lowerdown(f)
    fsm *f;
{
    switch( f->state ){
    case CLOSED:
	f->state = INITIAL;
	break;

    case STOPPED:
	f->state = STARTING;
	if( f->callbacks->starting )
	    (*f->callbacks->starting)(f);
	break;

    case CLOSING:
	f->state = INITIAL;
	UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	break;

    case STOPPING:
    case REQSENT:
    case ACKRCVD:
    case ACKSENT:
	f->state = STARTING;
	UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	break;

    case OPENED:
	if( f->callbacks->down )
	    (*f->callbacks->down)(f);
	f->state = STARTING;
	break;

    default:
	FSMDEBUG((f, LOG_DEBUG, "Down event in state %d!", f->state));
    }
}


/*
 * fsm_open - Link is allowed to come up.
 */
void
fsm_open(f)
    fsm *f;
{
    switch( f->state ){
    case INITIAL:
	f->state = STARTING;
	if( f->callbacks->starting )
	    (*f->callbacks->starting)(f);
	break;

    case CLOSED:
	if( f->flags & OPT_SILENT )
	    f->state = STOPPED;
	else {
	    /* Send an initial configure-request */
	    fsm_sconfreq(f, 0);
	    f->state = REQSENT;
	}
	break;

    case CLOSING:
	f->state = STOPPING;
	/* fall through */
    case STOPPED:
    case OPENED:
	if( f->flags & OPT_RESTART ){
	    fsm_lowerdown(f);
	    fsm_lowerup(f);
	}
	break;
    }
}


/*
 * fsm_close - Start closing connection.
 *
 * Cancel timeouts and either initiate close or possibly go directly to
 * the CLOSED state.
 */
void
fsm_close(f, reason)
    fsm *f;
    const char *reason;
{
    f->term_reason = (char *)reason;
    f->term_reason_len = (reason == NULL? 0: strlen(reason));
    switch( f->state ){
    case STARTING:
	f->state = INITIAL;
	break;
    case STOPPED:
	f->state = CLOSED;
	break;
    case STOPPING:
	f->state = CLOSING;
	break;

    case REQSENT:
    case ACKRCVD:
    case ACKSENT:
    case OPENED:
	if( f->state != OPENED )
	    UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	else if( f->callbacks->down )
	    (*f->callbacks->down)(f);	/* Inform upper layers we're down */

	/* Init restart counter, send Terminate-Request */
	f->retransmits = f->maxtermtransmits;
	fsm_sdata(f, TERMREQ, f->reqid = ++f->id,
		  (u_char *) f->term_reason, f->term_reason_len);
	TIMEOUT(fsm_timeout, f, f->timeouttime);
	--f->retransmits;

	f->state = CLOSING;
	break;
    }
}


/*
 * fsm_timeout - Timeout expired.
 */
static void
fsm_timeout(arg)
    void *arg;
{
    fsm *f = (fsm *) arg;

    switch (f->state) {
    case CLOSING:
    case STOPPING:
	if( f->retransmits <= 0 ){
	    /*
	     * We've waited for an ack long enough.  Peer probably heard us.
	     */
	    f->state = (f->state == CLOSING)? CLOSED: STOPPED;
	    if( f->callbacks->finished )
		(*f->callbacks->finished)(f);
	} else {
	    /* Send Terminate-Request */
	    fsm_sdata(f, TERMREQ, f->reqid = ++f->id,
		      (u_char *) f->term_reason, f->term_reason_len);
	    TIMEOUT(fsm_timeout, f, f->timeouttime);
	    --f->retransmits;
	}
	break;

    case REQSENT:
    case ACKRCVD:
    case ACKSENT:
	if (f->retransmits <= 0) {
	    fsm_log(f, LOG_WARNING, "timeout sending Config-Requests\n");
	    f->state = STOPPED;
	    if( (f->flags & OPT_PASSIVE) == 0 && f->callbacks->finished )
		(*f->callbacks->finished)(f);

	} else {
	    /* Retransmit the configure-request */
	    if (f->callbacks->retransmit)
		(*f->callbacks->retransmit)(f);
	    fsm_sconfreq(f, 1);		/* Re-send Configure-Request */
	    if( f->state == ACKRCVD )
		f->state = REQSENT;
	}
	break;

    default:
	FSMDEBUG((f, LOG_DEBUG, "Timeout event in state %d!", f->state));
    }
}


/*
 * fsm_input - Input packet.
 */
void
fsm_input(f, inpacket, l)
    fsm *f;
    u_char *inpacket;
    int l;
{
    u_char *inp;
    u_char code, id;
    int len;

    /*
     * Parse header (code, id and length).
     * If packet too short, drop it.
     */
    inp = inpacket;
    if (l < HEADERLEN) {
	FSMDEBUG((f, LOG_DEBUG, "fsm_input(): Rcvd short header."));
	return;
    }
    GETCHAR(code, inp);
    GETCHAR(id, inp);
    GETSHORT(len, inp);
    if (len < HEADERLEN) {
	FSMDEBUG((f, LOG_DEBUG, "fsm_input(): Rcvd illegal length."));
	return;
    }
    if (len > l) {
	FSMDEBUG((f, LOG_DEBUG, "fsm_input(): Rcvd short packet."));
	return;
    }
    len -= HEADERLEN;		/* subtract header length */

    if( f->state == INITIAL || f->state == STARTING ){
	FSMDEBUG((f, LOG_DEBUG, "fsm_input(): Rcvd packet in state %d.",
	    f->state));
	return;
    }

    /*
     * Action depends on code.
     */
    switch (code) {
    case CONFREQ:
	fsm_rconfreq(f, id, inp, len);
	break;

    case CONFACK:
	fsm_rconfack(f, id, inp, len);
	break;

    case CONFNAK:
    case CONFREJ:
	fsm_rconfnakrej(f, code, id, inp, len);
	break;

    case TERMREQ:
	fsm_rtermreq(f, id, inp, len);
	break;

    case TERMACK:
	fsm_rtermack(f);
	break;

    case CODEREJ:
	fsm_rcoderej(f, inp, len);
	break;

    default:
	if( !f->callbacks->extcode
	   || !(*f->callbacks->extcode)(f, code, id, inp, len) )
	    fsm_sdata(f, CODEREJ, ++f->id, inpacket, len + HEADERLEN);
	break;
    }
}


/*
 * fsm_rconfreq - Receive Configure-Request.
 */
static void
fsm_rconfreq(f, id, inp, len)
    fsm *f;
    u_char id;
    u_char *inp;
    int len;
{
    int code, reject_if_disagree;

    switch( f->state ){
    case CLOSED:
	/* Go away, we're closed */
	fsm_sdata(f, TERMACK, id, NULL, 0);
	return;
    case CLOSING:
    case STOPPING:
	return;

    case OPENED:
	/* Go down and restart negotiation */
	if( f->callbacks->down )
	    (*f->callbacks->down)(f);	/* Inform upper layers */
	fsm_sconfreq(f, 0);		/* Send initial Configure-Request */
	break;

    case STOPPED:
	/* Negotiation started by our peer */
	fsm_sconfreq(f, 0);		/* Send initial Configure-Request */
	f->state = REQSENT;
	break;
    }

    /*
     * Pass the requested configuration options
     * to protocol-specific code for checking.
     */
    if (f->callbacks->reqci){		/* Check CI */
	reject_if_disagree = (f->nakloops >= f->maxnakloops);
	code = (*f->callbacks->reqci)(f, inp, &len, reject_if_disagree);
    } else if (len)
	code = CONFREJ;			/* Reject all CI */
    else
	code = CONFACK;

    /* send the Ack, Nak or Rej to the peer */
    fsm_sdata(f, code, id, inp, len);

    if (code == CONFACK) {
	if (f->state == ACKRCVD) {
	    UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	    f->state = OPENED;
	    if (f->callbacks->up)
		(*f->callbacks->up)(f);	/* Inform upper layers */
	} else
	    f->state = ACKSENT;
	f->nakloops = 0;

    } else {
	/* we sent CONFNAK or CONFREJ */
	if (f->state != ACKRCVD)
	    f->state = REQSENT;
	if( code == CONFNAK )
	    ++f->nakloops;
    }
}


/*
 * fsm_rconfack - Receive Configure-Ack.
 */
static void
fsm_rconfack(f, id, inp, len)
    fsm *f;
    int id;
    u_char *inp;
    int len;
{
    if (id != f->reqid || f->seen_ack)		/* Expected id? */
	return;					/* Nope, toss... */
    if( !(f->callbacks->ackci? (*f->callbacks->ackci)(f, inp, len):
	  (len == 0)) ){
	/* Ack is bad - ignore it */
	fsm_log(f, LOG_ERR, "Received bad configure-ack: %p(%d)", inp, len);
	return;
    }
    f->seen_ack = 1;

    switch (f->state) {
    case CLOSED:
    case STOPPED:
	fsm_sdata(f, TERMACK, id, NULL, 0);
	break;

    case REQSENT:
	f->state = ACKRCVD;
	f->retransmits = f->maxconfreqtransmits;
	break;

    case ACKRCVD:
	/* Huh? an extra valid Ack? oh well... */
	UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	fsm_sconfreq(f, 0);
	f->state = REQSENT;
	break;

    case ACKSENT:
	UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	f->state = OPENED;
	f->retransmits = f->maxconfreqtransmits;
	if (f->callbacks->up)
	    (*f->callbacks->up)(f);	/* Inform upper layers */
	break;

    case OPENED:
	/* Go down and restart negotiation */
	if (f->callbacks->down)
	    (*f->callbacks->down)(f);	/* Inform upper layers */
	fsm_sconfreq(f, 0);		/* Send initial Configure-Request */
	f->state = REQSENT;
	break;
    }
}


/*
 * fsm_rconfnakrej - Receive Configure-Nak or Configure-Reject.
 */
static void
fsm_rconfnakrej(f, code, id, inp, len)
    fsm *f;
    int code, id;
    u_char *inp;
    int len;
{
    int (*proc)(fsm *, u_char *, int);
    int ret;

    if (id != f->reqid || f->seen_ack)	/* Expected id? */
	return;				/* Nope, toss... */
    proc = (code == CONFNAK)? f->callbacks->nakci: f->callbacks->rejci;
    if (!proc || !(ret = proc(f, inp, len))) {
	/* Nak/reject is bad - ignore it */
	fsm_log(f, LOG_INFO, "Received bad configure-%s: %p(%d)",
	    (code == CONFNAK)? "nak" : "rej", inp, len);
	return;
    }
    f->seen_ack = 1;

    switch (f->state) {
    case CLOSED:
    case STOPPED:
	fsm_sdata(f, TERMACK, id, NULL, 0);
	break;

    case REQSENT:
    case ACKSENT:
	/* They didn't agree to what we wanted - try another request */
	UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	if (ret < 0)
	    f->state = STOPPED;		/* kludge for stopping CCP */
	else
	    fsm_sconfreq(f, 0);		/* Send Configure-Request */
	break;

    case ACKRCVD:
	/* Got a Nak/reject when we had already had an Ack?? oh well... */
	UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	fsm_sconfreq(f, 0);
	f->state = REQSENT;
	break;

    case OPENED:
	/* Go down and restart negotiation */
	if (f->callbacks->down)
	    (*f->callbacks->down)(f);	/* Inform upper layers */
	fsm_sconfreq(f, 0);		/* Send initial Configure-Request */
	f->state = REQSENT;
	break;
    }
}


/*
 * fsm_rtermreq - Receive Terminate-Req.
 */
static void
fsm_rtermreq(f, id, p, len)
    fsm *f;
    int id;
    u_char *p;
    int len;
{
    switch (f->state) {
    case ACKRCVD:
    case ACKSENT:
	f->state = REQSENT;		/* Start over but keep trying */
	break;

    case OPENED:
	fsm_log(f, LOG_INFO, "terminated by peer");
	if (f->callbacks->down)
	    (*f->callbacks->down)(f);	/* Inform upper layers */
	f->retransmits = 0;
	f->state = STOPPING;
	TIMEOUT(fsm_timeout, f, f->timeouttime);
	break;
    }

    fsm_sdata(f, TERMACK, id, NULL, 0);
}


/*
 * fsm_rtermack - Receive Terminate-Ack.
 */
static void
fsm_rtermack(f)
    fsm *f;
{
    switch (f->state) {
    case CLOSING:
	UNTIMEOUT(fsm_timeout, f);
	f->state = CLOSED;
	if( f->callbacks->finished )
	    (*f->callbacks->finished)(f);
	break;
    case STOPPING:
	UNTIMEOUT(fsm_timeout, f);
	f->state = STOPPED;
	if( f->callbacks->finished )
	    (*f->callbacks->finished)(f);
	break;

    case ACKRCVD:
	f->state = REQSENT;
	break;

    case OPENED:
	if (f->callbacks->down)
	    (*f->callbacks->down)(f);	/* Inform upper layers */
	fsm_sconfreq(f, 0);
	f->state = REQSENT;
	break;
    }
}


/*
 * fsm_rcoderej - Receive an Code-Reject.
 */
static void
fsm_rcoderej(f, inp, len)
    fsm *f;
    u_char *inp;
    int len;
{
    u_char code, id;

    if (len < HEADERLEN) {
	FSMDEBUG((f, LOG_DEBUG,
	    "fsm_rcoderej: Rcvd short Code-Reject packet!"));
	return;
    }
    GETCHAR(code, inp);
    GETCHAR(id, inp);
    fsm_log(f, LOG_INFO,
	"%s: Rcvd Code-Reject for code %d, id %d", PROTO_NAME(f), code, id);

    if( f->state == ACKRCVD )
	f->state = REQSENT;
}


/*
 * fsm_protreject - Peer doesn't speak this protocol.
 *
 * Treat this as a catastrophic error (RXJ-).
 */
void
fsm_protreject(f)
    fsm *f;
{
    switch( f->state ){
    case CLOSING:
	UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	/* fall through */
    case CLOSED:
	f->state = CLOSED;
	if( f->callbacks->finished )
	    (*f->callbacks->finished)(f);
	break;

    case STOPPING:
    case REQSENT:
    case ACKRCVD:
    case ACKSENT:
	UNTIMEOUT(fsm_timeout, f);	/* Cancel timeout */
	/* fall through */
    case STOPPED:
	f->state = STOPPED;
	if( f->callbacks->finished )
	    (*f->callbacks->finished)(f);
	break;

    case OPENED:
	if( f->callbacks->down )
	    (*f->callbacks->down)(f);

	/* Init restart counter, send Terminate-Request */
	f->retransmits = f->maxtermtransmits;
	fsm_sdata(f, TERMREQ, f->reqid = ++f->id,
		  (u_char *) f->term_reason, f->term_reason_len);
	TIMEOUT(fsm_timeout, f, f->timeouttime);
	--f->retransmits;

	f->state = STOPPING;
	break;

    default:
	FSMDEBUG((f, LOG_DEBUG,
	    "Protocol-reject event in state %d!", f->state));
    }
}


/*
 * fsm_sconfreq - Send a Configure-Request.
 */
static void
fsm_sconfreq(f, retransmit)
    fsm *f;
    int retransmit;
{
    u_char *outp;
    int cilen;

    if( f->state != REQSENT && f->state != ACKRCVD && f->state != ACKSENT ){
	/* Not currently negotiating - reset options */
	if( f->callbacks->resetci )
	    (*f->callbacks->resetci)(f);
	f->nakloops = 0;
    }

    if( !retransmit ){
	/* New request - reset retransmission counter, use new ID */
	f->retransmits = f->maxconfreqtransmits;
	f->reqid = ++f->id;
    }

    f->seen_ack = 0;

    /*
     * Make up the request packet
     */
    outp = f->ppp->outpacket_buf + PPP_HDRLEN + HEADERLEN;
    if( f->callbacks->cilen && f->callbacks->addci ){
	cilen = (*f->callbacks->cilen)(f);
	if( cilen > f->ppp->mru - HEADERLEN )
	    cilen = f->ppp->mru - HEADERLEN;
	if (f->callbacks->addci)
	    (*f->callbacks->addci)(f, outp, &cilen);
    } else
	cilen = 0;

    /* send the request to our peer */
    fsm_sdata(f, CONFREQ, f->reqid, outp, cilen);

    /* start the retransmit timer */
    --f->retransmits;
    TIMEOUT(fsm_timeout, f, f->timeouttime);
}


/*
 * fsm_sdata - Send some data.
 *
 * Used for all packets sent to our peer by this module.
 */
void
fsm_sdata(f, code, id, data, datalen)
    fsm *f;
    u_char code, id;
    u_char *data;
    int datalen;
{
    ppp_output(f->ppp, f->protocol, code, id, data, datalen);
}


void
fsm_log(fsm *f, uint32_t prio, const char *fmt, ...)
{
    char logbuf[BUFSIZ];
    va_list ap;

    FSM_ASSERT(f != NULL);
    FSM_ASSERT(f->callbacks != NULL);

    va_start(ap, fmt);
    snprintf(logbuf, sizeof(logbuf), "ppp id=%u layer=%s %s", f->ppp->id,
	PROTO_NAME(f), fmt);
    vlog_printf(prio, logbuf, ap);
    va_end(ap);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: fsm.c,v 1.9 2017/05/30 17:22:00 yasuoka Exp $ */
2
3			/**@file
4			* This file was adapted from NetBSD:/usr/src/usr.sbin/pppd/pppd/fsm.c
5			*/
6			/*
7			* fsm.c is simple and it can be use without modifications. So keep the
8			* original as much as possible. (2005/04 yasuoka)
9			*
10			* XXX: I think the same message for initial configure-request is a bad idea
11			* XXX: on resending configure-request.(yasuoka)
12			*/
13			/* $NetBSD: fsm.c,v 1.13 2000/09/23 22:39:35 christos Exp $ */
14
15			/*
16			* fsm.c - {Link, IP} Control Protocol Finite State Machine.
17			*
18			* Copyright (c) 1989 Carnegie Mellon University.
19			* All rights reserved.
20			*
21			* Redistribution and use in source and binary forms are permitted
22			* provided that the above copyright notice and this paragraph are
23			* duplicated in all such forms and that any documentation,
24			* advertising materials, and other materials related to such
25			* distribution and use acknowledge that the software was developed
26			* by Carnegie Mellon University. The name of the
27			* University may not be used to endorse or promote products derived
28			* from this software without specific prior written permission.
29			* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
30			* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
31			* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
32			*/
33
34			/*
35			* TODO:
36			* Randomize fsm id on link/init.
37			* Deal with variable outgoing MTU.
38			*/
39
40			#include <stdio.h>
41			#include <string.h>
42			#include <sys/types.h>
43			#include <stdarg.h>
44			#include <syslog.h>
45			#include <stdlib.h>
46
47			/* npppd related headers below */
48			#include <sys/time.h>
49			#include <sys/socket.h>
50			#include <netinet/in.h>
51			#include <net/if_dl.h>
52			#include <time.h>
53			#include <event.h>
54			#include "debugutil.h"
55			#include "slist.h"
56			#include "npppd.h"
57			#include "fsm.h"
58
59			#ifdef FSM_DEBUG
60			#define FSMDEBUG(x) fsm_log x
61			#define FSM_ASSERT(x) ASSERT(x)
62			#else
63			#define FSMDEBUG(x)
64			#define FSM_ASSERT(x)
65			#endif
66
67			#define HEADERLEN 4
68
69			#ifdef RCSID
70			static const char rcsid[] = RCSID;
71			#endif
72
73			static void fsm_timeout(void *);
74			static void fsm_rconfreq(fsm , int, u_char , int);
75			static void fsm_rconfack(fsm , int, u_char , int);
76			static void fsm_rconfnakrej(fsm , int, int, u_char , int);
77			static void fsm_rtermreq(fsm , int, u_char , int);
78			static void fsm_rtermack(fsm *);
79			static void fsm_rcoderej(fsm , u_char , int);
80			static void fsm_sconfreq(fsm *, int);
81
82			#define PROTO_NAME(f) ((f)->callbacks->proto_name)
83
84			void
85			fsm_evtimer_timeout(int fd, short evtype, void *ctx)
86			{
87			struct evtimer_wrap *wrap;
88
89			wrap = ctx;
90			wrap->func(wrap->ctx);
91			}
92
93
94			/*
95			* fsm_init - Initialize fsm.
96			*
97			* Initialize fsm state.
98			*/
99			void
100			fsm_init(f)
101			fsm *f;
102			{
103			f->state = INITIAL;
104			f->flags = 0;
105			f->id = 0; /* XXX Start with random id? */
106			f->timeouttime = DEFTIMEOUT;
107			f->maxconfreqtransmits = DEFMAXCONFREQS;
108			f->maxtermtransmits = DEFMAXTERMREQS;
109			f->maxnakloops = DEFMAXNAKLOOPS;
110			f->term_reason_len = 0;
111			memset(&f->timerctx, 0, sizeof(f->timerctx));
112			f->timerctx.ctx = f;
113			}
114
115
116			/*
117			* fsm_lowerup - The lower layer is up.
118			*/
119			void
120			fsm_lowerup(f)
121			fsm *f;
122			{
123			switch( f->state ){
124			case INITIAL:
125			f->state = CLOSED;
126			break;
127
128			case STARTING:
129			if( f->flags & OPT_SILENT )
130			f->state = STOPPED;
131			else {
132			/* Send an initial configure-request */
133			fsm_sconfreq(f, 0);
134			f->state = REQSENT;
135			}
136			break;
137
138			default:
139			FSMDEBUG((f, LOG_DEBUG, "Up event in state %d!", f->state));
140			}
141			}
142
143
144			/*
145			* fsm_lowerdown - The lower layer is down.
146			*
147			* Cancel all timeouts and inform upper layers.
148			*/
149			void
150			fsm_lowerdown(f)
151			fsm *f;
152			{
153			switch( f->state ){
154			case CLOSED:
155			f->state = INITIAL;
156			break;
157
158			case STOPPED:
159			f->state = STARTING;
160			if( f->callbacks->starting )
161			(*f->callbacks->starting)(f);
162			break;
163
164			case CLOSING:
165			f->state = INITIAL;
166			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
167			break;
168
169			case STOPPING:
170			case REQSENT:
171			case ACKRCVD:
172			case ACKSENT:
173			f->state = STARTING;
174			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
175			break;
176
177			case OPENED:
178			if( f->callbacks->down )
179			(*f->callbacks->down)(f);
180			f->state = STARTING;
181			break;
182
183			default:
184			FSMDEBUG((f, LOG_DEBUG, "Down event in state %d!", f->state));
185			}
186			}
187
188
189			/*
190			* fsm_open - Link is allowed to come up.
191			*/
192			void
193			fsm_open(f)
194			fsm *f;
195			{
196			switch( f->state ){
197			case INITIAL:
198			f->state = STARTING;
199			if( f->callbacks->starting )
200			(*f->callbacks->starting)(f);
201			break;
202
203			case CLOSED:
204			if( f->flags & OPT_SILENT )
205			f->state = STOPPED;
206			else {
207			/* Send an initial configure-request */
208			fsm_sconfreq(f, 0);
209			f->state = REQSENT;
210			}
211			break;
212
213			case CLOSING:
214			f->state = STOPPING;
215			/* fall through */
216			case STOPPED:
217			case OPENED:
218			if( f->flags & OPT_RESTART ){
219			fsm_lowerdown(f);
220			fsm_lowerup(f);
221			}
222			break;
223			}
224			}
225
226
227			/*
228			* fsm_close - Start closing connection.
229			*
230			* Cancel timeouts and either initiate close or possibly go directly to
231			* the CLOSED state.
232			*/
233			void
234			fsm_close(f, reason)
235			fsm *f;
236			const char *reason;
237			{
238			f->term_reason = (char *)reason;
239			f->term_reason_len = (reason == NULL? 0: strlen(reason));
240			switch( f->state ){
241			case STARTING:
242			f->state = INITIAL;
243			break;
244			case STOPPED:
245			f->state = CLOSED;
246			break;
247			case STOPPING:
248			f->state = CLOSING;
249			break;
250
251			case REQSENT:
252			case ACKRCVD:
253			case ACKSENT:
254			case OPENED:
255			if( f->state != OPENED )
256			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
257			else if( f->callbacks->down )
258			(f->callbacks->down)(f); / Inform upper layers we're down */
259
260			/* Init restart counter, send Terminate-Request */
261			f->retransmits = f->maxtermtransmits;
262			fsm_sdata(f, TERMREQ, f->reqid = ++f->id,
263			(u_char *) f->term_reason, f->term_reason_len);
264			TIMEOUT(fsm_timeout, f, f->timeouttime);
265			--f->retransmits;
266
267			f->state = CLOSING;
268			break;
269			}
270			}
271
272
273			/*
274			* fsm_timeout - Timeout expired.
275			*/
276			static void
277			fsm_timeout(arg)
278			void *arg;
279			{
280			fsm f = (fsm ) arg;
281
282			switch (f->state) {
283			case CLOSING:
284			case STOPPING:
285			if( f->retransmits <= 0 ){
286			/*
287			* We've waited for an ack long enough. Peer probably heard us.
288			*/
289			f->state = (f->state == CLOSING)? CLOSED: STOPPED;
290			if( f->callbacks->finished )
291			(*f->callbacks->finished)(f);
292			} else {
293			/* Send Terminate-Request */
294			fsm_sdata(f, TERMREQ, f->reqid = ++f->id,
295			(u_char *) f->term_reason, f->term_reason_len);
296			TIMEOUT(fsm_timeout, f, f->timeouttime);
297			--f->retransmits;
298			}
299			break;
300
301			case REQSENT:
302			case ACKRCVD:
303			case ACKSENT:
304			if (f->retransmits <= 0) {
305			fsm_log(f, LOG_WARNING, "timeout sending Config-Requests\n");
306			f->state = STOPPED;
307			if( (f->flags & OPT_PASSIVE) == 0 && f->callbacks->finished )
308			(*f->callbacks->finished)(f);
309
310			} else {
311			/* Retransmit the configure-request */
312			if (f->callbacks->retransmit)
313			(*f->callbacks->retransmit)(f);
314			fsm_sconfreq(f, 1); /* Re-send Configure-Request */
315			if( f->state == ACKRCVD )
316			f->state = REQSENT;
317			}
318			break;
319
320			default:
321			FSMDEBUG((f, LOG_DEBUG, "Timeout event in state %d!", f->state));
322			}
323			}
324
325
326			/*
327			* fsm_input - Input packet.
328			*/
329			void
330			fsm_input(f, inpacket, l)
331			fsm *f;
332			u_char *inpacket;
333			int l;
334			{
335			u_char *inp;
336			u_char code, id;
337			int len;
338
339			/*
340			* Parse header (code, id and length).
341			* If packet too short, drop it.
342			*/
343			inp = inpacket;
344			if (l < HEADERLEN) {
345			FSMDEBUG((f, LOG_DEBUG, "fsm_input(): Rcvd short header."));
346			return;
347			}
348			GETCHAR(code, inp);
349			GETCHAR(id, inp);
350			GETSHORT(len, inp);
351			if (len < HEADERLEN) {
352			FSMDEBUG((f, LOG_DEBUG, "fsm_input(): Rcvd illegal length."));
353			return;
354			}
355			if (len > l) {
356			FSMDEBUG((f, LOG_DEBUG, "fsm_input(): Rcvd short packet."));
357			return;
358			}
359			len -= HEADERLEN; /* subtract header length */
360
361			if( f->state == INITIAL \|\| f->state == STARTING ){
362			FSMDEBUG((f, LOG_DEBUG, "fsm_input(): Rcvd packet in state %d.",
363			f->state));
364			return;
365			}
366
367			/*
368			* Action depends on code.
369			*/
370			switch (code) {
371			case CONFREQ:
372			fsm_rconfreq(f, id, inp, len);
373			break;
374
375			case CONFACK:
376			fsm_rconfack(f, id, inp, len);
377			break;
378
379			case CONFNAK:
380			case CONFREJ:
381			fsm_rconfnakrej(f, code, id, inp, len);
382			break;
383
384			case TERMREQ:
385			fsm_rtermreq(f, id, inp, len);
386			break;
387
388			case TERMACK:
389			fsm_rtermack(f);
390			break;
391
392			case CODEREJ:
393			fsm_rcoderej(f, inp, len);
394			break;
395
396			default:
397			if( !f->callbacks->extcode
398			\|\| !(*f->callbacks->extcode)(f, code, id, inp, len) )
399			fsm_sdata(f, CODEREJ, ++f->id, inpacket, len + HEADERLEN);
400			break;
401			}
402			}
403
404
405			/*
406			* fsm_rconfreq - Receive Configure-Request.
407			*/
408			static void
409			fsm_rconfreq(f, id, inp, len)
410			fsm *f;
411			u_char id;
412			u_char *inp;
413			int len;
414			{
415			int code, reject_if_disagree;
416
417			switch( f->state ){
418			case CLOSED:
419			/* Go away, we're closed */
420			fsm_sdata(f, TERMACK, id, NULL, 0);
421			return;
422			case CLOSING:
423			case STOPPING:
424			return;
425
426			case OPENED:
427			/* Go down and restart negotiation */
428			if( f->callbacks->down )
429			(f->callbacks->down)(f); / Inform upper layers */
430			fsm_sconfreq(f, 0); /* Send initial Configure-Request */
431			break;
432
433			case STOPPED:
434			/* Negotiation started by our peer */
435			fsm_sconfreq(f, 0); /* Send initial Configure-Request */
436			f->state = REQSENT;
437			break;
438			}
439
440			/*
441			* Pass the requested configuration options
442			* to protocol-specific code for checking.
443			*/
444			if (f->callbacks->reqci){ /* Check CI */
445			reject_if_disagree = (f->nakloops >= f->maxnakloops);
446			code = (*f->callbacks->reqci)(f, inp, &len, reject_if_disagree);
447			} else if (len)
448			code = CONFREJ; /* Reject all CI */
449			else
450			code = CONFACK;
451
452			/* send the Ack, Nak or Rej to the peer */
453			fsm_sdata(f, code, id, inp, len);
454
455			if (code == CONFACK) {
456			if (f->state == ACKRCVD) {
457			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
458			f->state = OPENED;
459			if (f->callbacks->up)
460			(f->callbacks->up)(f); / Inform upper layers */
461			} else
462			f->state = ACKSENT;
463			f->nakloops = 0;
464
465			} else {
466			/* we sent CONFNAK or CONFREJ */
467			if (f->state != ACKRCVD)
468			f->state = REQSENT;
469			if( code == CONFNAK )
470			++f->nakloops;
471			}
472			}
473
474
475			/*
476			* fsm_rconfack - Receive Configure-Ack.
477			*/
478			static void
479			fsm_rconfack(f, id, inp, len)
480			fsm *f;
481			int id;
482			u_char *inp;
483			int len;
484			{
485			if (id != f->reqid \|\| f->seen_ack) /* Expected id? */
486			return; /* Nope, toss... */
487			if( !(f->callbacks->ackci? (*f->callbacks->ackci)(f, inp, len):
488			(len == 0)) ){
489			/* Ack is bad - ignore it */
490			fsm_log(f, LOG_ERR, "Received bad configure-ack: %p(%d)", inp, len);
491			return;
492			}
493			f->seen_ack = 1;
494
495			switch (f->state) {
496			case CLOSED:
497			case STOPPED:
498			fsm_sdata(f, TERMACK, id, NULL, 0);
499			break;
500
501			case REQSENT:
502			f->state = ACKRCVD;
503			f->retransmits = f->maxconfreqtransmits;
504			break;
505
506			case ACKRCVD:
507			/* Huh? an extra valid Ack? oh well... */
508			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
509			fsm_sconfreq(f, 0);
510			f->state = REQSENT;
511			break;
512
513			case ACKSENT:
514			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
515			f->state = OPENED;
516			f->retransmits = f->maxconfreqtransmits;
517			if (f->callbacks->up)
518			(f->callbacks->up)(f); / Inform upper layers */
519			break;
520
521			case OPENED:
522			/* Go down and restart negotiation */
523			if (f->callbacks->down)
524			(f->callbacks->down)(f); / Inform upper layers */
525			fsm_sconfreq(f, 0); /* Send initial Configure-Request */
526			f->state = REQSENT;
527			break;
528			}
529			}
530
531
532			/*
533			* fsm_rconfnakrej - Receive Configure-Nak or Configure-Reject.
534			*/
535			static void
536			fsm_rconfnakrej(f, code, id, inp, len)
537			fsm *f;
538			int code, id;
539			u_char *inp;
540			int len;
541			{
542			int (proc)(fsm , u_char *, int);
543			int ret;
544
545			if (id != f->reqid \|\| f->seen_ack) /* Expected id? */
546			return; /* Nope, toss... */
547			proc = (code == CONFNAK)? f->callbacks->nakci: f->callbacks->rejci;
548			if (!proc \|\| !(ret = proc(f, inp, len))) {
549			/* Nak/reject is bad - ignore it */
550			fsm_log(f, LOG_INFO, "Received bad configure-%s: %p(%d)",
551			(code == CONFNAK)? "nak" : "rej", inp, len);
552			return;
553			}
554			f->seen_ack = 1;
555
556			switch (f->state) {
557			case CLOSED:
558			case STOPPED:
559			fsm_sdata(f, TERMACK, id, NULL, 0);
560			break;
561
562			case REQSENT:
563			case ACKSENT:
564			/* They didn't agree to what we wanted - try another request */
565			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
566			if (ret < 0)
567			f->state = STOPPED; /* kludge for stopping CCP */
568			else
569			fsm_sconfreq(f, 0); /* Send Configure-Request */
570			break;
571
572			case ACKRCVD:
573			/* Got a Nak/reject when we had already had an Ack?? oh well... */
574			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
575			fsm_sconfreq(f, 0);
576			f->state = REQSENT;
577			break;
578
579			case OPENED:
580			/* Go down and restart negotiation */
581			if (f->callbacks->down)
582			(f->callbacks->down)(f); / Inform upper layers */
583			fsm_sconfreq(f, 0); /* Send initial Configure-Request */
584			f->state = REQSENT;
585			break;
586			}
587			}
588
589
590			/*
591			* fsm_rtermreq - Receive Terminate-Req.
592			*/
593			static void
594			fsm_rtermreq(f, id, p, len)
595			fsm *f;
596			int id;
597			u_char *p;
598			int len;
599			{
600			switch (f->state) {
601			case ACKRCVD:
602			case ACKSENT:
603			f->state = REQSENT; /* Start over but keep trying */
604			break;
605
606			case OPENED:
607			fsm_log(f, LOG_INFO, "terminated by peer");
608			if (f->callbacks->down)
609			(f->callbacks->down)(f); / Inform upper layers */
610			f->retransmits = 0;
611			f->state = STOPPING;
612			TIMEOUT(fsm_timeout, f, f->timeouttime);
613			break;
614			}
615
616			fsm_sdata(f, TERMACK, id, NULL, 0);
617			}
618
619
620			/*
621			* fsm_rtermack - Receive Terminate-Ack.
622			*/
623			static void
624			fsm_rtermack(f)
625			fsm *f;
626			{
627			switch (f->state) {
628			case CLOSING:
629			UNTIMEOUT(fsm_timeout, f);
630			f->state = CLOSED;
631			if( f->callbacks->finished )
632			(*f->callbacks->finished)(f);
633			break;
634			case STOPPING:
635			UNTIMEOUT(fsm_timeout, f);
636			f->state = STOPPED;
637			if( f->callbacks->finished )
638			(*f->callbacks->finished)(f);
639			break;
640
641			case ACKRCVD:
642			f->state = REQSENT;
643			break;
644
645			case OPENED:
646			if (f->callbacks->down)
647			(f->callbacks->down)(f); / Inform upper layers */
648			fsm_sconfreq(f, 0);
649			f->state = REQSENT;
650			break;
651			}
652			}
653
654
655			/*
656			* fsm_rcoderej - Receive an Code-Reject.
657			*/
658			static void
659			fsm_rcoderej(f, inp, len)
660			fsm *f;
661			u_char *inp;
662			int len;
663			{
664			u_char code, id;
665
666			if (len < HEADERLEN) {
667			FSMDEBUG((f, LOG_DEBUG,
668			"fsm_rcoderej: Rcvd short Code-Reject packet!"));
669			return;
670			}
671			GETCHAR(code, inp);
672			GETCHAR(id, inp);
673			fsm_log(f, LOG_INFO,
674			"%s: Rcvd Code-Reject for code %d, id %d", PROTO_NAME(f), code, id);
675
676			if( f->state == ACKRCVD )
677			f->state = REQSENT;
678			}
679
680
681			/*
682			* fsm_protreject - Peer doesn't speak this protocol.
683			*
684			* Treat this as a catastrophic error (RXJ-).
685			*/
686			void
687			fsm_protreject(f)
688			fsm *f;
689			{
690			switch( f->state ){
691			case CLOSING:
692			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
693			/* fall through */
694			case CLOSED:
695			f->state = CLOSED;
696			if( f->callbacks->finished )
697			(*f->callbacks->finished)(f);
698			break;
699
700			case STOPPING:
701			case REQSENT:
702			case ACKRCVD:
703			case ACKSENT:
704			UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
705			/* fall through */
706			case STOPPED:
707			f->state = STOPPED;
708			if( f->callbacks->finished )
709			(*f->callbacks->finished)(f);
710			break;
711
712			case OPENED:
713			if( f->callbacks->down )
714			(*f->callbacks->down)(f);
715
716			/* Init restart counter, send Terminate-Request */
717			f->retransmits = f->maxtermtransmits;
718			fsm_sdata(f, TERMREQ, f->reqid = ++f->id,
719			(u_char *) f->term_reason, f->term_reason_len);
720			TIMEOUT(fsm_timeout, f, f->timeouttime);
721			--f->retransmits;
722
723			f->state = STOPPING;
724			break;
725
726			default:
727			FSMDEBUG((f, LOG_DEBUG,
728			"Protocol-reject event in state %d!", f->state));
729			}
730			}
731
732
733			/*
734			* fsm_sconfreq - Send a Configure-Request.
735			*/
736			static void
737			fsm_sconfreq(f, retransmit)
738			fsm *f;
739			int retransmit;
740			{
741			u_char *outp;
742			int cilen;
743
744			if( f->state != REQSENT && f->state != ACKRCVD && f->state != ACKSENT ){
745			/* Not currently negotiating - reset options */
746			if( f->callbacks->resetci )
747			(*f->callbacks->resetci)(f);
748			f->nakloops = 0;
749			}
750
751			if( !retransmit ){
752			/* New request - reset retransmission counter, use new ID */
753			f->retransmits = f->maxconfreqtransmits;
754			f->reqid = ++f->id;
755			}
756
757			f->seen_ack = 0;
758
759			/*
760			* Make up the request packet
761			*/
762			outp = f->ppp->outpacket_buf + PPP_HDRLEN + HEADERLEN;
763			if( f->callbacks->cilen && f->callbacks->addci ){
764			cilen = (*f->callbacks->cilen)(f);
765			if( cilen > f->ppp->mru - HEADERLEN )
766			cilen = f->ppp->mru - HEADERLEN;
767			if (f->callbacks->addci)
768			(*f->callbacks->addci)(f, outp, &cilen);
769			} else
770			cilen = 0;
771
772			/* send the request to our peer */
773			fsm_sdata(f, CONFREQ, f->reqid, outp, cilen);
774
775			/* start the retransmit timer */
776			--f->retransmits;
777			TIMEOUT(fsm_timeout, f, f->timeouttime);
778			}
779
780
781			/*
782			* fsm_sdata - Send some data.
783			*
784			* Used for all packets sent to our peer by this module.
785			*/
786			void
787			fsm_sdata(f, code, id, data, datalen)
788			fsm *f;
789			u_char code, id;
790			u_char *data;
791			int datalen;
792			{
793			ppp_output(f->ppp, f->protocol, code, id, data, datalen);
794			}
795
796
797			void
798			fsm_log(fsm f, uint32_t prio, const char fmt, ...)
799			{
800			char logbuf[BUFSIZ];
801			va_list ap;
802
803			FSM_ASSERT(f != NULL);
804			FSM_ASSERT(f->callbacks != NULL);
805
806			va_start(ap, fmt);
807			snprintf(logbuf, sizeof(logbuf), "ppp id=%u layer=%s %s", f->ppp->id,
808			PROTO_NAME(f), fmt);
809			vlog_printf(prio, logbuf, ap);
810			va_end(ap);
811			}