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freebsd/usr.sbin/ppp/fsm.c
Brian Somers 49b239e0d2 Allow an optional delay when specifying "set openmode active".
The delay defaults to 1 sec (as it always has) unless we've done
a ~p in interactive mode or we've actually detected a HDLC frame.
This is now cleanly implemented (via async timers) so that it is
possible for LCP to come up despite the delay if an LCP REQ is
received.

This will hopefully solve situations with slow servers or slirp
scenarios (where ECHO is left on the port for a second or so before
the peer enters packet mode).

Also, ~p in interactive mode no longer changes the value of the default
openmode delay and -dedicated mode enters packet mode in the right state
according to the value of openmode.
1998-01-20 22:47:48 +00:00

821 lines
18 KiB
C

/*
* PPP Finite State Machine for LCP/IPCP
*
* Written by Toshiharu OHNO (tony-o@iij.ad.jp)
*
* Copyright (C) 1993, Internet Initiative Japan, Inc. All rights reserverd.
*
* 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 the Internet Initiative Japan, Inc. The name of the
* IIJ 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.
*
* $Id: fsm.c,v 1.26 1998/01/10 01:55:09 brian Exp $
*
* TODO:
* o Refer loglevel for log output
* o Better option log display
*/
#include <sys/param.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <termios.h>
#include "command.h"
#include "mbuf.h"
#include "log.h"
#include "defs.h"
#include "timer.h"
#include "fsm.h"
#include "hdlc.h"
#include "lqr.h"
#include "lcpproto.h"
#include "lcp.h"
#include "ccp.h"
#include "modem.h"
#include "loadalias.h"
#include "vars.h"
u_char AckBuff[200];
u_char NakBuff[200];
u_char RejBuff[100];
u_char ReqBuff[200];
u_char *ackp = NULL;
u_char *nakp = NULL;
u_char *rejp = NULL;
static void FsmSendConfigReq(struct fsm *);
static void FsmSendTerminateReq(struct fsm *);
static void FsmInitRestartCounter(struct fsm *);
char const *StateNames[] = {
"Initial", "Starting", "Closed", "Stopped", "Closing", "Stopping",
"Req-Sent", "Ack-Rcvd", "Ack-Sent", "Opened",
};
static void
StoppedTimeout(void *v)
{
struct fsm *fp = (struct fsm *)v;
LogPrintf(fp->LogLevel, "Stopped timer expired\n");
if (fp->OpenTimer.state == TIMER_RUNNING) {
LogPrintf(LogWARN, "%s: aborting open delay due to stopped timer\n",
fp->name);
StopTimer(&fp->OpenTimer);
}
if (modem != -1)
DownConnection();
else
FsmDown(fp);
}
void
FsmInit(struct fsm * fp)
{
LogPrintf(LogDEBUG, "FsmInit\n");
fp->state = ST_INITIAL;
fp->reqid = 1;
fp->restart = 1;
fp->maxconfig = 3;
}
static void
NewState(struct fsm * fp, int new)
{
LogPrintf(fp->LogLevel, "State change %s --> %s\n",
StateNames[fp->state], StateNames[new]);
if (fp->state == ST_STOPPED && fp->StoppedTimer.state == TIMER_RUNNING)
StopTimer(&fp->StoppedTimer);
fp->state = new;
if ((new >= ST_INITIAL && new <= ST_STOPPED) || (new == ST_OPENED)) {
StopTimer(&fp->FsmTimer);
if (new == ST_STOPPED && fp->StoppedTimer.load) {
fp->StoppedTimer.state = TIMER_STOPPED;
fp->StoppedTimer.func = StoppedTimeout;
fp->StoppedTimer.arg = (void *) fp;
StartTimer(&fp->StoppedTimer);
}
}
}
void
FsmOutput(struct fsm * fp, u_int code, u_int id, u_char * ptr, int count)
{
int plen;
struct fsmheader lh;
struct mbuf *bp;
plen = sizeof(struct fsmheader) + count;
lh.code = code;
lh.id = id;
lh.length = htons(plen);
bp = mballoc(plen, MB_FSM);
memcpy(MBUF_CTOP(bp), &lh, sizeof(struct fsmheader));
if (count)
memcpy(MBUF_CTOP(bp) + sizeof(struct fsmheader), ptr, count);
LogDumpBp(LogDEBUG, "FsmOutput", bp);
HdlcOutput(PRI_LINK, fp->proto, bp);
}
static void
FsmOpenNow(void *v)
{
struct fsm *fp = (struct fsm *)v;
StopTimer(&fp->OpenTimer);
if (fp->state <= ST_STOPPED) {
FsmInitRestartCounter(fp);
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
}
}
void
FsmOpen(struct fsm * fp)
{
switch (fp->state) {
case ST_INITIAL:
(fp->LayerStart) (fp);
NewState(fp, ST_STARTING);
break;
case ST_STARTING:
break;
case ST_CLOSED:
if (fp->open_mode == OPEN_PASSIVE) {
NewState(fp, ST_STOPPED);
} else if (fp->open_mode > 0) {
if (fp->open_mode > 1)
LogPrintf(LogPHASE, "Entering STOPPED state for %d seconds\n",
fp->open_mode);
NewState(fp, ST_STOPPED);
fp->OpenTimer.state = TIMER_STOPPED;
fp->OpenTimer.load = fp->open_mode * SECTICKS;
fp->OpenTimer.func = FsmOpenNow;
fp->OpenTimer.arg = (void *)fp;
StartTimer(&fp->OpenTimer);
} else
FsmOpenNow(fp);
break;
case ST_STOPPED: /* XXX: restart option */
case ST_REQSENT:
case ST_ACKRCVD:
case ST_ACKSENT:
case ST_OPENED: /* XXX: restart option */
break;
case ST_CLOSING: /* XXX: restart option */
case ST_STOPPING: /* XXX: restart option */
NewState(fp, ST_STOPPING);
break;
}
}
void
FsmUp(struct fsm * fp)
{
switch (fp->state) {
case ST_INITIAL:
NewState(fp, ST_CLOSED);
break;
case ST_STARTING:
FsmInitRestartCounter(fp);
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
break;
default:
LogPrintf(fp->LogLevel, "Oops, Up at %s\n", StateNames[fp->state]);
break;
}
}
void
FsmDown(struct fsm * fp)
{
switch (fp->state) {
case ST_CLOSED:
case ST_CLOSING:
NewState(fp, ST_INITIAL);
break;
case ST_STOPPED:
(fp->LayerStart) (fp);
/* Fall into.. */
case ST_STOPPING:
case ST_REQSENT:
case ST_ACKRCVD:
case ST_ACKSENT:
NewState(fp, ST_STARTING);
break;
case ST_OPENED:
(fp->LayerDown) (fp);
NewState(fp, ST_STARTING);
break;
}
}
void
FsmClose(struct fsm * fp)
{
switch (fp->state) {
case ST_STARTING:
NewState(fp, ST_INITIAL);
break;
case ST_STOPPED:
NewState(fp, ST_CLOSED);
break;
case ST_STOPPING:
NewState(fp, ST_CLOSING);
break;
case ST_OPENED:
(fp->LayerDown) (fp);
/* Fall down */
case ST_REQSENT:
case ST_ACKRCVD:
case ST_ACKSENT:
FsmInitRestartCounter(fp);
FsmSendTerminateReq(fp);
NewState(fp, ST_CLOSING);
break;
}
}
/*
* Send functions
*/
static void
FsmSendConfigReq(struct fsm * fp)
{
if (--fp->maxconfig > 0) {
(fp->SendConfigReq) (fp);
StartTimer(&fp->FsmTimer); /* Start restart timer */
fp->restart--; /* Decrement restart counter */
} else {
FsmClose(fp);
}
}
static void
FsmSendTerminateReq(struct fsm * fp)
{
LogPrintf(fp->LogLevel, "SendTerminateReq.\n");
FsmOutput(fp, CODE_TERMREQ, fp->reqid++, NULL, 0);
(fp->SendTerminateReq) (fp);
StartTimer(&fp->FsmTimer); /* Start restart timer */
fp->restart--; /* Decrement restart counter */
}
static void
FsmSendConfigAck(struct fsm * fp,
struct fsmheader * lhp,
u_char * option,
int count)
{
LogPrintf(fp->LogLevel, "SendConfigAck(%s)\n", StateNames[fp->state]);
(fp->DecodeConfig) (option, count, MODE_NOP);
FsmOutput(fp, CODE_CONFIGACK, lhp->id, option, count);
}
static void
FsmSendConfigRej(struct fsm * fp,
struct fsmheader * lhp,
u_char * option,
int count)
{
LogPrintf(fp->LogLevel, "SendConfigRej(%s)\n", StateNames[fp->state]);
(fp->DecodeConfig) (option, count, MODE_NOP);
FsmOutput(fp, CODE_CONFIGREJ, lhp->id, option, count);
}
static void
FsmSendConfigNak(struct fsm * fp,
struct fsmheader * lhp,
u_char * option,
int count)
{
LogPrintf(fp->LogLevel, "SendConfigNak(%s)\n", StateNames[fp->state]);
(fp->DecodeConfig) (option, count, MODE_NOP);
FsmOutput(fp, CODE_CONFIGNAK, lhp->id, option, count);
}
/*
* Timeout actions
*/
static void
FsmTimeout(void *v)
{
struct fsm *fp = (struct fsm *)v;
if (fp->restart) {
switch (fp->state) {
case ST_CLOSING:
case ST_STOPPING:
FsmSendTerminateReq(fp);
break;
case ST_REQSENT:
case ST_ACKSENT:
FsmSendConfigReq(fp);
break;
case ST_ACKRCVD:
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
break;
}
StartTimer(&fp->FsmTimer);
} else {
switch (fp->state) {
case ST_CLOSING:
NewState(fp, ST_CLOSED);
(fp->LayerFinish) (fp);
break;
case ST_STOPPING:
NewState(fp, ST_STOPPED);
(fp->LayerFinish) (fp);
break;
case ST_REQSENT: /* XXX: 3p */
case ST_ACKSENT:
case ST_ACKRCVD:
NewState(fp, ST_STOPPED);
(fp->LayerFinish) (fp);
break;
}
}
}
static void
FsmInitRestartCounter(struct fsm * fp)
{
StopTimer(&fp->FsmTimer);
fp->FsmTimer.state = TIMER_STOPPED;
fp->FsmTimer.func = FsmTimeout;
fp->FsmTimer.arg = (void *) fp;
(fp->InitRestartCounter) (fp);
}
/*
* Actions when receive packets
*/
static void
FsmRecvConfigReq(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
/* RCR */
{
int plen, flen;
int ackaction = 0;
plen = plength(bp);
flen = ntohs(lhp->length) - sizeof *lhp;
if (plen < flen) {
LogPrintf(LogERROR, "FsmRecvConfigReq: plen (%d) < flen (%d)\n",
plen, flen);
pfree(bp);
return;
}
/*
* Check and process easy case
*/
switch (fp->state) {
case ST_INITIAL:
case ST_STARTING:
LogPrintf(fp->LogLevel, "Oops, RCR in %s.\n", StateNames[fp->state]);
pfree(bp);
return;
case ST_CLOSED:
(fp->SendTerminateAck) (fp);
pfree(bp);
return;
case ST_CLOSING:
LogPrintf(fp->LogLevel, "Error: Got ConfigReq while state = %d\n",
fp->state);
case ST_STOPPING:
pfree(bp);
return;
}
(fp->DecodeConfig) (MBUF_CTOP(bp), flen, MODE_REQ);
if (nakp == NakBuff && rejp == RejBuff)
ackaction = 1;
switch (fp->state) {
case ST_OPENED:
(fp->LayerDown) (fp);
FsmSendConfigReq(fp);
break;
case ST_STOPPED:
FsmInitRestartCounter(fp);
FsmSendConfigReq(fp);
break;
}
if (rejp != RejBuff)
FsmSendConfigRej(fp, lhp, RejBuff, rejp - RejBuff);
if (nakp != NakBuff)
FsmSendConfigNak(fp, lhp, NakBuff, nakp - NakBuff);
if (ackaction)
FsmSendConfigAck(fp, lhp, AckBuff, ackp - AckBuff);
switch (fp->state) {
case ST_STOPPED:
case ST_OPENED:
if (ackaction)
NewState(fp, ST_ACKSENT);
else
NewState(fp, ST_REQSENT);
break;
case ST_REQSENT:
if (ackaction)
NewState(fp, ST_ACKSENT);
break;
case ST_ACKRCVD:
if (ackaction) {
NewState(fp, ST_OPENED);
(fp->LayerUp) (fp);
}
break;
case ST_ACKSENT:
if (!ackaction)
NewState(fp, ST_REQSENT);
break;
}
pfree(bp);
}
static void
FsmRecvConfigAck(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
/* RCA */
{
switch (fp->state) {
case ST_CLOSED:
case ST_STOPPED:
(fp->SendTerminateAck) (fp);
break;
case ST_CLOSING:
case ST_STOPPING:
break;
case ST_REQSENT:
FsmInitRestartCounter(fp);
NewState(fp, ST_ACKRCVD);
break;
case ST_ACKRCVD:
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
break;
case ST_ACKSENT:
FsmInitRestartCounter(fp);
NewState(fp, ST_OPENED);
(fp->LayerUp) (fp);
break;
case ST_OPENED:
(fp->LayerDown) (fp);
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
break;
}
pfree(bp);
}
static void
FsmRecvConfigNak(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
/* RCN */
{
int plen, flen;
plen = plength(bp);
flen = ntohs(lhp->length) - sizeof *lhp;
if (plen < flen) {
pfree(bp);
return;
}
/*
* Check and process easy case
*/
switch (fp->state) {
case ST_INITIAL:
case ST_STARTING:
LogPrintf(fp->LogLevel, "Oops, RCN in %s.\n", StateNames[fp->state]);
pfree(bp);
return;
case ST_CLOSED:
case ST_STOPPED:
(fp->SendTerminateAck) (fp);
pfree(bp);
return;
case ST_CLOSING:
case ST_STOPPING:
pfree(bp);
return;
}
(fp->DecodeConfig) (MBUF_CTOP(bp), flen, MODE_NAK);
switch (fp->state) {
case ST_REQSENT:
case ST_ACKSENT:
FsmInitRestartCounter(fp);
FsmSendConfigReq(fp);
break;
case ST_OPENED:
(fp->LayerDown) (fp);
/* Fall down */
case ST_ACKRCVD:
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
break;
}
pfree(bp);
}
static void
FsmRecvTermReq(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
/* RTR */
{
switch (fp->state) {
case ST_INITIAL:
case ST_STARTING:
LogPrintf(fp->LogLevel, "Oops, RTR in %s\n", StateNames[fp->state]);
break;
case ST_CLOSED:
case ST_STOPPED:
case ST_CLOSING:
case ST_STOPPING:
case ST_REQSENT:
(fp->SendTerminateAck) (fp);
break;
case ST_ACKRCVD:
case ST_ACKSENT:
(fp->SendTerminateAck) (fp);
NewState(fp, ST_REQSENT);
break;
case ST_OPENED:
(fp->LayerDown) (fp);
(fp->SendTerminateAck) (fp);
StartTimer(&fp->FsmTimer); /* Start restart timer */
fp->restart = 0;
NewState(fp, ST_STOPPING);
break;
}
pfree(bp);
}
static void
FsmRecvTermAck(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
/* RTA */
{
switch (fp->state) {
case ST_CLOSING:
NewState(fp, ST_CLOSED);
(fp->LayerFinish) (fp);
break;
case ST_STOPPING:
NewState(fp, ST_STOPPED);
(fp->LayerFinish) (fp);
break;
case ST_ACKRCVD:
NewState(fp, ST_REQSENT);
break;
case ST_OPENED:
(fp->LayerDown) (fp);
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
break;
}
pfree(bp);
}
static void
FsmRecvConfigRej(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
/* RCJ */
{
int plen, flen;
plen = plength(bp);
flen = ntohs(lhp->length) - sizeof *lhp;
if (plen < flen) {
pfree(bp);
return;
}
LogPrintf(fp->LogLevel, "RecvConfigRej.\n");
/*
* Check and process easy case
*/
switch (fp->state) {
case ST_INITIAL:
case ST_STARTING:
LogPrintf(fp->LogLevel, "Oops, RCJ in %s.\n", StateNames[fp->state]);
pfree(bp);
return;
case ST_CLOSED:
case ST_STOPPED:
(fp->SendTerminateAck) (fp);
pfree(bp);
return;
case ST_CLOSING:
case ST_STOPPING:
pfree(bp);
return;
}
(fp->DecodeConfig) (MBUF_CTOP(bp), flen, MODE_REJ);
switch (fp->state) {
case ST_REQSENT:
case ST_ACKSENT:
FsmInitRestartCounter(fp);
FsmSendConfigReq(fp);
break;
case ST_OPENED:
(fp->LayerDown) (fp);
/* Fall down */
case ST_ACKRCVD:
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
break;
}
pfree(bp);
}
static void
FsmRecvCodeRej(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
LogPrintf(fp->LogLevel, "RecvCodeRej\n");
pfree(bp);
}
static void
FsmRecvProtoRej(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
u_short *sp, proto;
sp = (u_short *) MBUF_CTOP(bp);
proto = ntohs(*sp);
LogPrintf(fp->LogLevel, "-- Protocol (%04x) was rejected.\n", proto);
switch (proto) {
case PROTO_LQR:
StopLqr(LQM_LQR);
break;
case PROTO_CCP:
fp = &CcpFsm;
(fp->LayerFinish) (fp);
switch (fp->state) {
case ST_CLOSED:
case ST_CLOSING:
NewState(fp, ST_CLOSED);
default:
NewState(fp, ST_STOPPED);
break;
}
break;
}
pfree(bp);
}
static void
FsmRecvEchoReq(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
u_char *cp;
u_long *lp, magic;
cp = MBUF_CTOP(bp);
lp = (u_long *) cp;
magic = ntohl(*lp);
if (magic != LcpInfo.his_magic) {
LogPrintf(LogERROR, "RecvEchoReq: his magic is bad!!\n");
/* XXX: We should send terminate request */
}
if (fp->state == ST_OPENED) {
*lp = htonl(LcpInfo.want_magic); /* Insert local magic number */
LogPrintf(fp->LogLevel, "SendEchoRep(%s)\n", StateNames[fp->state]);
FsmOutput(fp, CODE_ECHOREP, lhp->id, cp, plength(bp));
}
pfree(bp);
}
static void
FsmRecvEchoRep(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
u_long *lp, magic;
lp = (u_long *) MBUF_CTOP(bp);
magic = ntohl(*lp);
/*
* Tolerate echo replies with either magic number
*/
if (magic != 0 && magic != LcpInfo.his_magic && magic != LcpInfo.want_magic) {
LogPrintf(LogERROR, "RecvEchoRep: his magic is wrong! expect: %x got: %x\n",
LcpInfo.his_magic, magic);
/*
* XXX: We should send terminate request. But poor implementation may die
* as a result.
*/
}
RecvEchoLqr(bp);
pfree(bp);
}
static void
FsmRecvDiscReq(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
LogPrintf(fp->LogLevel, "RecvDiscReq\n");
pfree(bp);
}
static void
FsmRecvIdent(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
LogPrintf(fp->LogLevel, "RecvIdent\n");
pfree(bp);
}
static void
FsmRecvTimeRemain(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
LogPrintf(fp->LogLevel, "RecvTimeRemain\n");
pfree(bp);
}
static void
FsmRecvResetReq(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
LogPrintf(fp->LogLevel, "RecvResetReq(%d)\n", lhp->id);
CcpRecvResetReq(fp);
/*
* All sendable compressed packets are queued in the PRI_NORMAL modem
* output queue.... dump 'em to the priority queue so that they arrive
* at the peer before our ResetAck.
*/
SequenceQueues();
LogPrintf(fp->LogLevel, "SendResetAck(%d)\n", lhp->id);
FsmOutput(fp, CODE_RESETACK, lhp->id, NULL, 0);
pfree(bp);
}
static void
FsmRecvResetAck(struct fsm * fp, struct fsmheader * lhp, struct mbuf * bp)
{
LogPrintf(fp->LogLevel, "RecvResetAck(%d)\n", lhp->id);
CcpResetInput(lhp->id);
fp->reqid++;
pfree(bp);
}
static const struct fsmcodedesc FsmCodes[] = {
{FsmRecvConfigReq, "Configure Request",},
{FsmRecvConfigAck, "Configure Ack",},
{FsmRecvConfigNak, "Configure Nak",},
{FsmRecvConfigRej, "Configure Reject",},
{FsmRecvTermReq, "Terminate Request",},
{FsmRecvTermAck, "Terminate Ack",},
{FsmRecvCodeRej, "Code Reject",},
{FsmRecvProtoRej, "Protocol Reject",},
{FsmRecvEchoReq, "Echo Request",},
{FsmRecvEchoRep, "Echo Reply",},
{FsmRecvDiscReq, "Discard Request",},
{FsmRecvIdent, "Ident",},
{FsmRecvTimeRemain, "Time Remain",},
{FsmRecvResetReq, "Reset Request",},
{FsmRecvResetAck, "Reset Ack",},
};
void
FsmInput(struct fsm * fp, struct mbuf * bp)
{
int len;
struct fsmheader *lhp;
const struct fsmcodedesc *codep;
len = plength(bp);
if (len < sizeof(struct fsmheader)) {
pfree(bp);
return;
}
lhp = (struct fsmheader *) MBUF_CTOP(bp);
if (lhp->code == 0 || lhp->code > fp->max_code) {
pfree(bp); /* XXX: Should send code reject */
return;
}
bp->offset += sizeof(struct fsmheader);
bp->cnt -= sizeof(struct fsmheader);
codep = FsmCodes + lhp->code - 1;
LogPrintf(fp->LogLevel, "Received %s (%d) state = %s (%d)\n",
codep->name, lhp->id, StateNames[fp->state], fp->state);
if (LogIsKept(LogDEBUG))
LogMemory();
(codep->action) (fp, lhp, bp);
if (LogIsKept(LogDEBUG))
LogMemory();
}