/* * 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 1.7 1998/06/28 09:41:38 brian Exp $ * * TODO: * o Refer loglevel for log output * o Better option log display */ #include #include #include #include #include #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_int32_t *lp, magic; cp = MBUF_CTOP(bp); lp = (u_int32_t *) 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_int32_t *lp, magic; lp = (u_int32_t *) 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(); }