freebsd-src/usr.sbin/ppp/fsm.c
1997-02-22 16:15:28 +00:00

814 lines
16 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.
*
* $Id$
*
* TODO:
* o Refer loglevel for log output
* o Better option log display
*/
#include "fsm.h"
#include "hdlc.h"
#include "lqr.h"
#include "lcpproto.h"
#include "lcp.h"
#include "ccp.h"
void FsmSendConfigReq(struct fsm *fp);
void FsmSendTerminateReq(struct fsm *fp);
void FsmInitRestartCounter(struct fsm *fp);
void FsmTimeout(struct fsm *fp);
char const *StateNames[] = {
"Initial", "Starting", "Closed", "Stopped", "Closing", "Stopping",
"Req-Sent", "Ack-Rcvd", "Ack-Sent", "Opend",
};
void
FsmInit(fp)
struct fsm *fp;
{
#ifdef DEBUG
logprintf("FsmInit\n");
#endif
fp->state = ST_INITIAL;
fp->reqid = 1;
fp->restart = 1;
fp->maxconfig = 3;
}
void
NewState(fp, new)
struct fsm *fp;
int new;
{
LogPrintf(LOG_LCP_BIT, "%s: state change %s --> %s\n",
fp->name, StateNames[fp->state], StateNames[new]);
fp->state = new;
if ((new >= ST_INITIAL && new <= ST_STOPPED) || (new == ST_OPENED))
StopTimer(&fp->FsmTimer);
}
void
FsmOutput(fp, code, id, ptr, count)
struct fsm *fp;
u_int code, 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);
bcopy(&lh, MBUF_CTOP(bp), sizeof(struct fsmheader));
if (count)
bcopy(ptr, MBUF_CTOP(bp) + sizeof(struct fsmheader), count);
#ifdef DEBUG
DumpBp(bp);
#endif
HdlcOutput(PRI_LINK, fp->proto, bp);
}
void
FsmOpen(fp)
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 {
FsmInitRestartCounter(fp);
FsmSendConfigReq(fp);
NewState(fp, ST_REQSENT);
}
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(fp)
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(LOG_LCP_BIT, "%s: Oops, Up at %s\n",
fp->name, StateNames[fp->state]);
break;
}
}
void
FsmDown(fp)
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(fp)
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
*/
void
FsmSendConfigReq(fp)
struct fsm *fp;
{
if (--fp->maxconfig > 0) {
(fp->SendConfigReq)(fp);
StartTimer(&fp->FsmTimer); /* Start restart timer */
fp->restart--; /* Decrement restart counter */
} else {
FsmClose(fp);
}
}
void
FsmSendTerminateReq(fp)
struct fsm *fp;
{
LogPrintf(LOG_LCP_BIT, "%s: SendTerminateReq.\n", fp->name);
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(fp, lhp, option, count)
struct fsm *fp;
struct fsmheader *lhp;
u_char *option;
int count;
{
LogPrintf(LOG_LCP_BIT, "%s: SendConfigAck(%s)\n", fp->name, StateNames[fp->state]);
(fp->DecodeConfig)(option, count, MODE_NOP);
FsmOutput(fp, CODE_CONFIGACK, lhp->id, option, count);
}
static void
FsmSendConfigRej(fp, lhp, option, count)
struct fsm *fp;
struct fsmheader *lhp;
u_char *option;
int count;
{
LogPrintf(LOG_LCP_BIT, "%s: SendConfigRej(%s)\n", fp->name, StateNames[fp->state]);
(fp->DecodeConfig)(option, count, MODE_NOP);
FsmOutput(fp, CODE_CONFIGREJ, lhp->id, option, count);
}
static void
FsmSendConfigNak(fp, lhp, option, count)
struct fsm *fp;
struct fsmheader *lhp;
u_char *option;
int count;
{
LogPrintf(LOG_LCP_BIT, "%s: SendConfigNak(%s)\n",
fp->name, StateNames[fp->state]);
(fp->DecodeConfig)(option, count, MODE_NOP);
FsmOutput(fp, CODE_CONFIGNAK, lhp->id, option, count);
}
/*
* Timeout actions
*/
void
FsmTimeout(fp)
struct fsm *fp;
{
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;
}
}
}
void
FsmInitRestartCounter(fp)
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
*/
void
FsmRecvConfigReq(fp, lhp, bp) /* RCR */
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
int plen, flen;
int ackaction = 0;
plen = plength(bp);
flen = ntohs(lhp->length) - sizeof(*lhp);
if (plen < flen) {
logprintf("** 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(LOG_LCP_BIT, "%s: Oops, RCR in %s.\n",
fp->name, StateNames[fp->state]);
pfree(bp);
return;
case ST_CLOSED:
(fp->SendTerminateAck)(fp);
pfree(bp);
return;
case ST_CLOSING:
case ST_STOPPING:
logprintf("## state = %d\n", fp->state);
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);
}
void
FsmRecvConfigAck(fp, lhp, bp) /* RCA */
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
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);
}
void
FsmRecvConfigNak(fp, lhp, bp) /* RCN */
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
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(LOG_LCP_BIT, "%s: Oops, RCN in %s.\n",
fp->name, 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);
}
void
FsmRecvTermReq(fp, lhp, bp) /* RTR */
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
switch (fp->state) {
case ST_INITIAL:
case ST_STARTING:
LogPrintf(LOG_LCP_BIT, "%s: Oops, RTR in %s\n", fp->name,
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);
/* Zero Restart counter */
(fp->SendTerminateAck)(fp);
NewState(fp, ST_STOPPING);
break;
}
pfree(bp);
}
void
FsmRecvTermAck(fp, lhp, bp) /* RTA */
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
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);
}
void
FsmRecvConfigRej(fp, lhp, bp) /* RCJ */
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
int plen, flen;
plen = plength(bp);
flen = ntohs(lhp->length) - sizeof(*lhp);
if (plen < flen) {
pfree(bp);
return;
}
LogPrintf(LOG_LCP_BIT, "%s: RecvConfigRej.\n", fp->name);
/*
* Check and process easy case
*/
switch (fp->state) {
case ST_INITIAL:
case ST_STARTING:
LogPrintf(LOG_LCP_BIT, "%s: Oops, RCJ in %s.\n",
fp->name, 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);
}
void
FsmRecvCodeRej(fp, lhp, bp)
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
LogPrintf(LOG_LCP_BIT, "%s: RecvCodeRej\n", fp->name);
pfree(bp);
}
void
FsmRecvProtoRej(fp, lhp, bp)
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
u_short *sp, proto;
sp = (u_short *)MBUF_CTOP(bp);
proto = ntohs(*sp);
LogPrintf(LOG_LCP_BIT, "-- 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);
}
void
FsmRecvEchoReq(fp, lhp, bp)
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("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(LOG_LCP_BIT, "%s: SendEchoRep(%s)\n", fp->name, StateNames[fp->state]);
FsmOutput(fp, CODE_ECHOREP, lhp->id, cp, plength(bp));
}
pfree(bp);
}
void
FsmRecvEchoRep(fp, lhp, bp)
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("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);
}
void
FsmRecvDiscReq(fp, lhp, bp)
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
LogPrintf(LOG_LCP_BIT, "%s: RecvDiscReq\n", fp->name);
pfree(bp);
}
void
FsmRecvIdent(fp, lhp, bp)
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
LogPrintf(LOG_LCP_BIT, "%s: RecvIdent\n", fp->name);
pfree(bp);
}
void
FsmRecvTimeRemain(fp, lhp, bp)
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
LogPrintf(LOG_LCP_BIT, "%s: RecvTimeRemain\n", fp->name);
pfree(bp);
}
void
FsmRecvResetReq(fp, lhp, bp)
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
LogPrintf(LOG_LCP_BIT, "%s: RecvResetReq\n", fp->name);
CcpRecvResetReq(fp);
LogPrintf(LOG_LCP_BIT, "%s: SendResetAck\n", fp->name);
FsmOutput(fp, CODE_RESETACK, fp->reqid, NULL, 0);
pfree(bp);
}
void
FsmRecvResetAck(fp, lhp, bp)
struct fsm *fp;
struct fsmheader *lhp;
struct mbuf *bp;
{
LogPrintf(LOG_LCP_BIT, "%s: RecvResetAck\n", fp->name);
fp->reqid++;
pfree(bp);
}
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(fp, bp)
struct fsm *fp;
struct mbuf *bp;
{
int len;
struct fsmheader *lhp;
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(LOG_LCP_BIT, "%s: Received %s (%d) state = %s (%d)\n",
fp->name, codep->name, lhp->id, StateNames[fp->state], fp->state);
#ifdef DEBUG
LogMemory();
#endif
(codep->action)(fp, lhp, bp);
#ifdef DEBUG
LogMemory();
#endif
}