--- /dev/null
+/*****************************************************************************
+* fsm.c - Network Control Protocol Finite State Machine program file.
+*
+* Copyright (c) 2003 by Marc Boucher, Services Informatiques (MBSI) inc.
+* portions Copyright (c) 1997 by Global Election Systems Inc.
+*
+* The authors hereby grant permission to use, copy, modify, distribute,
+* and license this software and its documentation for any purpose, provided
+* that existing copyright notices are retained in all copies and that this
+* notice and the following disclaimer are included verbatim in any
+* distributions. No written agreement, license, or royalty fee is required
+* for any of the authorized uses.
+*
+* THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS *AS IS* AND ANY EXPRESS OR
+* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+* IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*
+******************************************************************************
+* REVISION HISTORY
+*
+* 03-01-01 Marc Boucher <marc@mbsi.ca>
+* Ported to lwIP.
+* 97-12-01 Guy Lancaster <lancasterg@acm.org>, Global Election Systems Inc.
+* Original based on BSD fsm.c.
+*****************************************************************************/
+/*
+ * 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 "lwip/opt.h"
+
+#if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
+
+#include "ppp.h"
+#include "pppdebug.h"
+
+#include "fsm.h"
+
+
+/*************************/
+/*** LOCAL DEFINITIONS ***/
+/*************************/
+
+#if PPP_DEBUG
+
+static const char *ppperr_strerr[] = {
+ "LS_INITIAL", /* LS_INITIAL 0 */
+ "LS_STARTING", /* LS_STARTING 1 */
+ "LS_CLOSED", /* LS_CLOSED 2 */
+ "LS_STOPPED", /* LS_STOPPED 3 */
+ "LS_CLOSING", /* LS_CLOSING 4 */
+ "LS_STOPPING", /* LS_STOPPING 5 */
+ "LS_REQSENT", /* LS_REQSENT 6 */
+ "LS_ACKRCVD", /* LS_ACKRCVD 7 */
+ "LS_ACKSENT", /* LS_ACKSENT 8 */
+ "LS_OPENED" /* LS_OPENED 9 */
+};
+
+#endif /* PPP_DEBUG */
+
+/************************/
+/*** LOCAL DATA TYPES ***/
+/************************/
+
+
+/***********************************/
+/*** LOCAL FUNCTION DECLARATIONS ***/
+/***********************************/
+static void fsm_timeout (void *);
+static void fsm_rconfreq (fsm *, u_char, 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)
+
+
+/******************************/
+/*** PUBLIC DATA STRUCTURES ***/
+/******************************/
+
+
+/*****************************/
+/*** LOCAL DATA STRUCTURES ***/
+/*****************************/
+int peer_mru[NUM_PPP];
+
+
+/***********************************/
+/*** PUBLIC FUNCTION DEFINITIONS ***/
+/***********************************/
+
+/*
+ * fsm_init - Initialize fsm.
+ *
+ * Initialize fsm state.
+ */
+void
+fsm_init(fsm *f)
+{
+ f->state = LS_INITIAL;
+ f->flags = 0;
+ f->id = 0; /* XXX Start with random id? */
+ f->timeouttime = FSM_DEFTIMEOUT;
+ f->maxconfreqtransmits = FSM_DEFMAXCONFREQS;
+ f->maxtermtransmits = FSM_DEFMAXTERMREQS;
+ f->maxnakloops = FSM_DEFMAXNAKLOOPS;
+ f->term_reason_len = 0;
+}
+
+
+/*
+ * fsm_lowerup - The lower layer is up.
+ */
+void
+fsm_lowerup(fsm *f)
+{
+ int oldState = f->state;
+
+ LWIP_UNUSED_ARG(oldState);
+
+ switch( f->state ) {
+ case LS_INITIAL:
+ f->state = LS_CLOSED;
+ break;
+
+ case LS_STARTING:
+ if( f->flags & OPT_SILENT ) {
+ f->state = LS_STOPPED;
+ } else {
+ /* Send an initial configure-request */
+ fsm_sconfreq(f, 0);
+ f->state = LS_REQSENT;
+ }
+ break;
+
+ default:
+ FSMDEBUG((LOG_INFO, "%s: Up event in state %d (%s)!\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+ }
+
+ FSMDEBUG((LOG_INFO, "%s: lowerup state %d (%s) -> %d (%s)\n",
+ PROTO_NAME(f), oldState, ppperr_strerr[oldState], f->state, ppperr_strerr[f->state]));
+}
+
+
+/*
+ * fsm_lowerdown - The lower layer is down.
+ *
+ * Cancel all timeouts and inform upper layers.
+ */
+void
+fsm_lowerdown(fsm *f)
+{
+ int oldState = f->state;
+
+ LWIP_UNUSED_ARG(oldState);
+
+ switch( f->state ) {
+ case LS_CLOSED:
+ f->state = LS_INITIAL;
+ break;
+
+ case LS_STOPPED:
+ f->state = LS_STARTING;
+ if( f->callbacks->starting ) {
+ (*f->callbacks->starting)(f);
+ }
+ break;
+
+ case LS_CLOSING:
+ f->state = LS_INITIAL;
+ UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
+ break;
+
+ case LS_STOPPING:
+ case LS_REQSENT:
+ case LS_ACKRCVD:
+ case LS_ACKSENT:
+ f->state = LS_STARTING;
+ UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
+ break;
+
+ case LS_OPENED:
+ if( f->callbacks->down ) {
+ (*f->callbacks->down)(f);
+ }
+ f->state = LS_STARTING;
+ break;
+
+ default:
+ FSMDEBUG((LOG_INFO, "%s: Down event in state %d (%s)!\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+ }
+
+ FSMDEBUG((LOG_INFO, "%s: lowerdown state %d (%s) -> %d (%s)\n",
+ PROTO_NAME(f), oldState, ppperr_strerr[oldState], f->state, ppperr_strerr[f->state]));
+}
+
+
+/*
+ * fsm_open - Link is allowed to come up.
+ */
+void
+fsm_open(fsm *f)
+{
+ int oldState = f->state;
+
+ LWIP_UNUSED_ARG(oldState);
+
+ switch( f->state ) {
+ case LS_INITIAL:
+ f->state = LS_STARTING;
+ if( f->callbacks->starting ) {
+ (*f->callbacks->starting)(f);
+ }
+ break;
+
+ case LS_CLOSED:
+ if( f->flags & OPT_SILENT ) {
+ f->state = LS_STOPPED;
+ } else {
+ /* Send an initial configure-request */
+ fsm_sconfreq(f, 0);
+ f->state = LS_REQSENT;
+ }
+ break;
+
+ case LS_CLOSING:
+ f->state = LS_STOPPING;
+ /* fall through */
+ case LS_STOPPED:
+ case LS_OPENED:
+ if( f->flags & OPT_RESTART ) {
+ fsm_lowerdown(f);
+ fsm_lowerup(f);
+ }
+ break;
+ }
+
+ FSMDEBUG((LOG_INFO, "%s: open state %d (%s) -> %d (%s)\n",
+ PROTO_NAME(f), oldState, ppperr_strerr[oldState], f->state, ppperr_strerr[f->state]));
+}
+
+
+/*
+ * fsm_close - Start closing connection.
+ *
+ * Cancel timeouts and either initiate close or possibly go directly to
+ * the LS_CLOSED state.
+ */
+void
+fsm_close(fsm *f, char *reason)
+{
+ int oldState = f->state;
+
+ LWIP_UNUSED_ARG(oldState);
+
+ f->term_reason = reason;
+ f->term_reason_len = (reason == NULL? 0: strlen(reason));
+ switch( f->state ) {
+ case LS_STARTING:
+ f->state = LS_INITIAL;
+ break;
+ case LS_STOPPED:
+ f->state = LS_CLOSED;
+ break;
+ case LS_STOPPING:
+ f->state = LS_CLOSING;
+ break;
+
+ case LS_REQSENT:
+ case LS_ACKRCVD:
+ case LS_ACKSENT:
+ case LS_OPENED:
+ if( f->state != LS_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 = LS_CLOSING;
+ break;
+ }
+
+ FSMDEBUG((LOG_INFO, "%s: close reason=%s state %d (%s) -> %d (%s)\n",
+ PROTO_NAME(f), reason, oldState, ppperr_strerr[oldState], f->state, ppperr_strerr[f->state]));
+}
+
+
+/*
+ * fsm_sdata - Send some data.
+ *
+ * Used for all packets sent to our peer by this module.
+ */
+void
+fsm_sdata( fsm *f, u_char code, u_char id, u_char *data, int datalen)
+{
+ u_char *outp;
+ int outlen;
+
+ /* Adjust length to be smaller than MTU */
+ outp = outpacket_buf[f->unit];
+ if (datalen > peer_mru[f->unit] - (int)HEADERLEN) {
+ datalen = peer_mru[f->unit] - HEADERLEN;
+ }
+ if (datalen && data != outp + PPP_HDRLEN + HEADERLEN) {
+ BCOPY(data, outp + PPP_HDRLEN + HEADERLEN, datalen);
+ }
+ outlen = datalen + HEADERLEN;
+ MAKEHEADER(outp, f->protocol);
+ PUTCHAR(code, outp);
+ PUTCHAR(id, outp);
+ PUTSHORT(outlen, outp);
+ pppWrite(f->unit, outpacket_buf[f->unit], outlen + PPP_HDRLEN);
+ FSMDEBUG((LOG_INFO, "fsm_sdata(%s): Sent code %d,%d,%d.\n",
+ PROTO_NAME(f), code, id, outlen));
+}
+
+
+/*
+ * fsm_input - Input packet.
+ */
+void
+fsm_input(fsm *f, u_char *inpacket, int l)
+{
+ u_char *inp = inpacket;
+ u_char code, id;
+ int len;
+
+ /*
+ * Parse header (code, id and length).
+ * If packet too short, drop it.
+ */
+ if (l < HEADERLEN) {
+ FSMDEBUG((LOG_WARNING, "fsm_input(%x): Rcvd short header.\n",
+ f->protocol));
+ return;
+ }
+ GETCHAR(code, inp);
+ GETCHAR(id, inp);
+ GETSHORT(len, inp);
+ if (len < HEADERLEN) {
+ FSMDEBUG((LOG_INFO, "fsm_input(%x): Rcvd illegal length.\n",
+ f->protocol));
+ return;
+ }
+ if (len > l) {
+ FSMDEBUG((LOG_INFO, "fsm_input(%x): Rcvd short packet.\n",
+ f->protocol));
+ return;
+ }
+ len -= HEADERLEN; /* subtract header length */
+
+ if( f->state == LS_INITIAL || f->state == LS_STARTING ) {
+ FSMDEBUG((LOG_INFO, "fsm_input(%x): Rcvd packet in state %d (%s).\n",
+ f->protocol, f->state, ppperr_strerr[f->state]));
+ return;
+ }
+ FSMDEBUG((LOG_INFO, "fsm_input(%s):%d,%d,%d\n", PROTO_NAME(f), code, id, l));
+ /*
+ * 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_protreject - Peer doesn't speak this protocol.
+ *
+ * Treat this as a catastrophic error (RXJ-).
+ */
+void
+fsm_protreject(fsm *f)
+{
+ switch( f->state ) {
+ case LS_CLOSING:
+ UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
+ /* fall through */
+ case LS_CLOSED:
+ f->state = LS_CLOSED;
+ if( f->callbacks->finished ) {
+ (*f->callbacks->finished)(f);
+ }
+ break;
+
+ case LS_STOPPING:
+ case LS_REQSENT:
+ case LS_ACKRCVD:
+ case LS_ACKSENT:
+ UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
+ /* fall through */
+ case LS_STOPPED:
+ f->state = LS_STOPPED;
+ if( f->callbacks->finished ) {
+ (*f->callbacks->finished)(f);
+ }
+ break;
+
+ case LS_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 = LS_STOPPING;
+ break;
+
+ default:
+ FSMDEBUG((LOG_INFO, "%s: Protocol-reject event in state %d (%s)!\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+ }
+}
+
+
+
+
+
+/**********************************/
+/*** LOCAL FUNCTION DEFINITIONS ***/
+/**********************************/
+
+/*
+ * fsm_timeout - Timeout expired.
+ */
+static void
+fsm_timeout(void *arg)
+{
+ fsm *f = (fsm *) arg;
+
+ switch (f->state) {
+ case LS_CLOSING:
+ case LS_STOPPING:
+ if( f->retransmits <= 0 ) {
+ FSMDEBUG((LOG_WARNING, "%s: timeout sending Terminate-Request state=%d (%s)\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+ /*
+ * We've waited for an ack long enough. Peer probably heard us.
+ */
+ f->state = (f->state == LS_CLOSING)? LS_CLOSED: LS_STOPPED;
+ if( f->callbacks->finished ) {
+ (*f->callbacks->finished)(f);
+ }
+ } else {
+ FSMDEBUG((LOG_WARNING, "%s: timeout resending Terminate-Requests state=%d (%s)\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+ /* 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 LS_REQSENT:
+ case LS_ACKRCVD:
+ case LS_ACKSENT:
+ if (f->retransmits <= 0) {
+ FSMDEBUG((LOG_WARNING, "%s: timeout sending Config-Requests state=%d (%s)\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+ f->state = LS_STOPPED;
+ if( (f->flags & OPT_PASSIVE) == 0 && f->callbacks->finished ) {
+ (*f->callbacks->finished)(f);
+ }
+ } else {
+ FSMDEBUG((LOG_WARNING, "%s: timeout resending Config-Request state=%d (%s)\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+ /* Retransmit the configure-request */
+ if (f->callbacks->retransmit) {
+ (*f->callbacks->retransmit)(f);
+ }
+ fsm_sconfreq(f, 1); /* Re-send Configure-Request */
+ if( f->state == LS_ACKRCVD ) {
+ f->state = LS_REQSENT;
+ }
+ }
+ break;
+
+ default:
+ FSMDEBUG((LOG_INFO, "%s: Timeout event in state %d (%s)!\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+ }
+}
+
+
+/*
+ * fsm_rconfreq - Receive Configure-Request.
+ */
+static void
+fsm_rconfreq(fsm *f, u_char id, u_char *inp, int len)
+{
+ int code, reject_if_disagree;
+
+ FSMDEBUG((LOG_INFO, "fsm_rconfreq(%s): Rcvd id %d state=%d (%s)\n",
+ PROTO_NAME(f), id, f->state, ppperr_strerr[f->state]));
+ switch( f->state ) {
+ case LS_CLOSED:
+ /* Go away, we're closed */
+ fsm_sdata(f, TERMACK, id, NULL, 0);
+ return;
+ case LS_CLOSING:
+ case LS_STOPPING:
+ return;
+
+ case LS_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 LS_STOPPED:
+ /* Negotiation started by our peer */
+ fsm_sconfreq(f, 0); /* Send initial Configure-Request */
+ f->state = LS_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, (u_char)code, id, inp, len);
+
+ if (code == CONFACK) {
+ if (f->state == LS_ACKRCVD) {
+ UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
+ f->state = LS_OPENED;
+ if (f->callbacks->up) {
+ (*f->callbacks->up)(f); /* Inform upper layers */
+ }
+ } else {
+ f->state = LS_ACKSENT;
+ }
+ f->nakloops = 0;
+ } else {
+ /* we sent CONFACK or CONFREJ */
+ if (f->state != LS_ACKRCVD) {
+ f->state = LS_REQSENT;
+ }
+ if( code == CONFNAK ) {
+ ++f->nakloops;
+ }
+ }
+}
+
+
+/*
+ * fsm_rconfack - Receive Configure-Ack.
+ */
+static void
+fsm_rconfack(fsm *f, int id, u_char *inp, int len)
+{
+ FSMDEBUG((LOG_INFO, "fsm_rconfack(%s): Rcvd id %d state=%d (%s)\n",
+ PROTO_NAME(f), id, f->state, ppperr_strerr[f->state]));
+
+ 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 */
+ FSMDEBUG((LOG_INFO, "%s: received bad Ack (length %d)\n",
+ PROTO_NAME(f), len));
+ return;
+ }
+ f->seen_ack = 1;
+
+ switch (f->state) {
+ case LS_CLOSED:
+ case LS_STOPPED:
+ fsm_sdata(f, TERMACK, (u_char)id, NULL, 0);
+ break;
+
+ case LS_REQSENT:
+ f->state = LS_ACKRCVD;
+ f->retransmits = f->maxconfreqtransmits;
+ break;
+
+ case LS_ACKRCVD:
+ /* Huh? an extra valid Ack? oh well... */
+ UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
+ fsm_sconfreq(f, 0);
+ f->state = LS_REQSENT;
+ break;
+
+ case LS_ACKSENT:
+ UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
+ f->state = LS_OPENED;
+ f->retransmits = f->maxconfreqtransmits;
+ if (f->callbacks->up) {
+ (*f->callbacks->up)(f); /* Inform upper layers */
+ }
+ break;
+
+ case LS_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 = LS_REQSENT;
+ break;
+ }
+}
+
+
+/*
+ * fsm_rconfnakrej - Receive Configure-Nak or Configure-Reject.
+ */
+static void
+fsm_rconfnakrej(fsm *f, int code, int id, u_char *inp, int len)
+{
+ int (*proc) (fsm *, u_char *, int);
+ int ret;
+
+ FSMDEBUG((LOG_INFO, "fsm_rconfnakrej(%s): Rcvd id %d state=%d (%s)\n",
+ PROTO_NAME(f), id, f->state, ppperr_strerr[f->state]));
+
+ 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 */
+ FSMDEBUG((LOG_INFO, "%s: received bad %s (length %d)\n",
+ PROTO_NAME(f), (code==CONFNAK? "Nak": "reject"), len));
+ return;
+ }
+ f->seen_ack = 1;
+
+ switch (f->state) {
+ case LS_CLOSED:
+ case LS_STOPPED:
+ fsm_sdata(f, TERMACK, (u_char)id, NULL, 0);
+ break;
+
+ case LS_REQSENT:
+ case LS_ACKSENT:
+ /* They didn't agree to what we wanted - try another request */
+ UNTIMEOUT(fsm_timeout, f); /* Cancel timeout */
+ if (ret < 0) {
+ f->state = LS_STOPPED; /* kludge for stopping CCP */
+ } else {
+ fsm_sconfreq(f, 0); /* Send Configure-Request */
+ }
+ break;
+
+ case LS_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 = LS_REQSENT;
+ break;
+
+ case LS_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 = LS_REQSENT;
+ break;
+ }
+}
+
+
+/*
+ * fsm_rtermreq - Receive Terminate-Req.
+ */
+static void
+fsm_rtermreq(fsm *f, int id, u_char *p, int len)
+{
+ LWIP_UNUSED_ARG(p);
+
+ FSMDEBUG((LOG_INFO, "fsm_rtermreq(%s): Rcvd id %d state=%d (%s)\n",
+ PROTO_NAME(f), id, f->state, ppperr_strerr[f->state]));
+
+ switch (f->state) {
+ case LS_ACKRCVD:
+ case LS_ACKSENT:
+ f->state = LS_REQSENT; /* Start over but keep trying */
+ break;
+
+ case LS_OPENED:
+ if (len > 0) {
+ FSMDEBUG((LOG_INFO, "%s terminated by peer (%x)\n", PROTO_NAME(f), p));
+ } else {
+ FSMDEBUG((LOG_INFO, "%s terminated by peer\n", PROTO_NAME(f)));
+ }
+ if (f->callbacks->down) {
+ (*f->callbacks->down)(f); /* Inform upper layers */
+ }
+ f->retransmits = 0;
+ f->state = LS_STOPPING;
+ TIMEOUT(fsm_timeout, f, f->timeouttime);
+ break;
+ }
+
+ fsm_sdata(f, TERMACK, (u_char)id, NULL, 0);
+}
+
+
+/*
+ * fsm_rtermack - Receive Terminate-Ack.
+ */
+static void
+fsm_rtermack(fsm *f)
+{
+ FSMDEBUG((LOG_INFO, "fsm_rtermack(%s): state=%d (%s)\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+
+ switch (f->state) {
+ case LS_CLOSING:
+ UNTIMEOUT(fsm_timeout, f);
+ f->state = LS_CLOSED;
+ if( f->callbacks->finished ) {
+ (*f->callbacks->finished)(f);
+ }
+ break;
+
+ case LS_STOPPING:
+ UNTIMEOUT(fsm_timeout, f);
+ f->state = LS_STOPPED;
+ if( f->callbacks->finished ) {
+ (*f->callbacks->finished)(f);
+ }
+ break;
+
+ case LS_ACKRCVD:
+ f->state = LS_REQSENT;
+ break;
+
+ case LS_OPENED:
+ if (f->callbacks->down) {
+ (*f->callbacks->down)(f); /* Inform upper layers */
+ }
+ fsm_sconfreq(f, 0);
+ break;
+ }
+}
+
+
+/*
+ * fsm_rcoderej - Receive an Code-Reject.
+ */
+static void
+fsm_rcoderej(fsm *f, u_char *inp, int len)
+{
+ u_char code, id;
+
+ FSMDEBUG((LOG_INFO, "fsm_rcoderej(%s): state=%d (%s)\n",
+ PROTO_NAME(f), f->state, ppperr_strerr[f->state]));
+
+ if (len < HEADERLEN) {
+ FSMDEBUG((LOG_INFO, "fsm_rcoderej: Rcvd short Code-Reject packet!\n"));
+ return;
+ }
+ GETCHAR(code, inp);
+ GETCHAR(id, inp);
+ FSMDEBUG((LOG_WARNING, "%s: Rcvd Code-Reject for code %d, id %d\n",
+ PROTO_NAME(f), code, id));
+
+ if( f->state == LS_ACKRCVD ) {
+ f->state = LS_REQSENT;
+ }
+}
+
+
+/*
+ * fsm_sconfreq - Send a Configure-Request.
+ */
+static void
+fsm_sconfreq(fsm *f, int retransmit)
+{
+ u_char *outp;
+ int cilen;
+
+ if( f->state != LS_REQSENT && f->state != LS_ACKRCVD && f->state != LS_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 = outpacket_buf[f->unit] + PPP_HDRLEN + HEADERLEN;
+ if( f->callbacks->cilen && f->callbacks->addci ) {
+ cilen = (*f->callbacks->cilen)(f);
+ if( cilen > peer_mru[f->unit] - (int)HEADERLEN ) {
+ cilen = peer_mru[f->unit] - 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);
+
+ FSMDEBUG((LOG_INFO, "%s: sending Configure-Request, id %d\n",
+ PROTO_NAME(f), f->reqid));
+}
+
+#endif /* PPP_SUPPORT */
