BSD 4_4_Lite2 release

[unix-history] / usr / src / sys / netns / spp_usrreq.c

diff --git a/usr/src/sys/netns/spp_usrreq.c b/usr/src/sys/netns/spp_usrreq.c
index 27d619e..7ce6723 100644 (file)
--- a/usr/src/sys/netns/spp_usrreq.c
+++ b/usr/src/sys/netns/spp_usrreq.c
@@ -1,28 +1,61 @@
-/*     spp_usrreq.c    6.1     85/05/30        */
-
-#include "param.h"
-#include "dir.h"
-#include "user.h"
-#include "mbuf.h"
-#include "protosw.h"
-#include "socket.h"
-#include "socketvar.h"
-#include "errno.h"
-
-#include "../net/if.h"
-#include "../net/route.h"
-#include "../netinet/tcp_fsm.h"
-#include "../netinet/tcp_timer.h"
-
-#include "ns.h"
-#include "ns_pcb.h"
-#include "idp.h"
-#include "idp_var.h"
-#include "ns_error.h"
-#include "sp.h"
-#include "spidp.h"
-#include "spp_var.h"
-#include "spp_debug.h"
+/*
+ * Copyright (c) 1984, 1985, 1986, 1987, 1993
+ *     The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *     This product includes software developed by the University of
+ *     California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND 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 REGENTS OR 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.
+ *
+ *     @(#)spp_usrreq.c        8.2 (Berkeley) 1/9/95
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/mbuf.h>
+#include <sys/protosw.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+#include <sys/errno.h>
+
+#include <net/if.h>
+#include <net/route.h>
+#include <netinet/tcp_fsm.h>
+
+#include <netns/ns.h>
+#include <netns/ns_pcb.h>
+#include <netns/idp.h>
+#include <netns/idp_var.h>
+#include <netns/ns_error.h>
+#include <netns/sp.h>
+#include <netns/spidp.h>
+#include <netns/spp_timer.h>
+#include <netns/spp_var.h>
+#include <netns/spp_debug.h>

 
 /*
  * SP protocol implementation.
 
 /*
  * SP protocol implementation.


@@ -35,23 +68,38 @@ spp_init()
 struct spidp spp_savesi;
 int traceallspps = 0;
 extern int sppconsdebug;
 struct spidp spp_savesi;
 int traceallspps = 0;
 extern int sppconsdebug;

-

 int spp_hardnosed;
 int spp_hardnosed;

+int spp_use_delack = 0;
+u_short spp_newchecks[50];
+
+/*ARGSUSED*/

 spp_input(m, nsp)
 spp_input(m, nsp)

-       register struct nspcb *nsp;

        register struct mbuf *m;
        register struct mbuf *m;

+       register struct nspcb *nsp;

 {
        register struct sppcb *cb;
        register struct spidp *si = mtod(m, struct spidp *);
        register struct socket *so;
 {
        register struct sppcb *cb;
        register struct spidp *si = mtod(m, struct spidp *);
        register struct socket *so;

-       int len; short ostate;
+       short ostate;

        int dropsocket = 0;
 
 
        int dropsocket = 0;
 
 

+       sppstat.spps_rcvtotal++;
+       if (nsp == 0) {
+               panic("No nspcb in spp_input\n");
+               return;
+       }

 
        cb = nstosppcb(nsp);
        if (cb == 0) goto bad;
 
 
        cb = nstosppcb(nsp);
        if (cb == 0) goto bad;
 

+       if (m->m_len < sizeof(*si)) {
+               if ((m = m_pullup(m, sizeof(*si))) == 0) {
+                       sppstat.spps_rcvshort++;
+                       return;
+               }
+               si = mtod(m, struct spidp *);
+       }

        si->si_seq = ntohs(si->si_seq);
        si->si_ack = ntohs(si->si_ack);
        si->si_alo = ntohs(si->si_alo);
        si->si_seq = ntohs(si->si_seq);
        si->si_ack = ntohs(si->si_ack);
        si->si_alo = ntohs(si->si_alo);


@@ -62,9 +110,10 @@ spp_input(m, nsp)
                spp_savesi = *si;
        }
        if (so->so_options & SO_ACCEPTCONN) {
                spp_savesi = *si;
        }
        if (so->so_options & SO_ACCEPTCONN) {

-               so = sonewconn(so);
+               struct sppcb *ocb = cb;
+
+               so = sonewconn(so, 0);

                if (so == 0) {
                if (so == 0) {

-                       spp_istat.nonucn++;

                        goto drop;
                }
                /*
                        goto drop;
                }
                /*


@@ -82,6 +131,9 @@ spp_input(m, nsp)
                nsp = (struct nspcb *)so->so_pcb;
                nsp->nsp_laddr = si->si_dna;
                cb = nstosppcb(nsp);
                nsp = (struct nspcb *)so->so_pcb;
                nsp->nsp_laddr = si->si_dna;
                cb = nstosppcb(nsp);

+               cb->s_mtu = ocb->s_mtu;         /* preserve sockopts */
+               cb->s_flags = ocb->s_flags;     /* preserve sockopts */
+               cb->s_flags2 = ocb->s_flags2;   /* preserve sockopts */

                cb->s_state = TCPS_LISTEN;
        }
 
                cb->s_state = TCPS_LISTEN;
        }
 


@@ -90,9 +142,10 @@ spp_input(m, nsp)
         * reset idle time and keep-alive timer;
         */
        cb->s_idle = 0;
         * reset idle time and keep-alive timer;
         */
        cb->s_idle = 0;

-       cb->s_timer[TCPT_KEEP] = TCPTV_KEEP;
+       cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;

 
        switch (cb->s_state) {
 
        switch (cb->s_state) {

+

        case TCPS_LISTEN:{
                struct mbuf *am;
                register struct sockaddr_ns *sns;
        case TCPS_LISTEN:{
                struct mbuf *am;
                register struct sockaddr_ns *sns;


@@ -112,6 +165,7 @@ spp_input(m, nsp)
                        goto drop;
                am->m_len = sizeof (struct sockaddr_ns);
                sns = mtod(am, struct sockaddr_ns *);
                        goto drop;
                am->m_len = sizeof (struct sockaddr_ns);
                sns = mtod(am, struct sockaddr_ns *);

+               sns->sns_len = sizeof(*sns);

                sns->sns_family = AF_NS;
                sns->sns_addr = si->si_sna;
                laddr = nsp->nsp_laddr;
                sns->sns_family = AF_NS;
                sns->sns_addr = si->si_sna;
                laddr = nsp->nsp_laddr;


@@ -124,69 +178,86 @@ spp_input(m, nsp)
                        goto drop;
                }
                (void) m_free(am);
                        goto drop;
                }
                (void) m_free(am);

-               cb->s_state = TCPS_SYN_RECEIVED;

                spp_template(cb);
                spp_template(cb);

+               dropsocket = 0;         /* committed to socket */

                cb->s_did = si->si_sid;
                cb->s_rack = si->si_ack;
                cb->s_ralo = si->si_alo;
                cb->s_did = si->si_sid;
                cb->s_rack = si->si_ack;
                cb->s_ralo = si->si_alo;

-               cb->s_flags |= SF_AK;
-               cb->s_timer[TCPT_KEEP] = TCPTV_KEEP;
-               dropsocket = 0;         /* committed to socket */
+#define THREEWAYSHAKE
+#ifdef THREEWAYSHAKE
+               cb->s_state = TCPS_SYN_RECEIVED;
+               cb->s_force = 1 + SPPT_KEEP;
+               sppstat.spps_accepts++;
+               cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
+               }
+               break;
+       /*
+        * This state means that we have heard a response
+        * to our acceptance of their connection
+        * It is probably logically unnecessary in this
+        * implementation.
+        */
+        case TCPS_SYN_RECEIVED: {
+               if (si->si_did!=cb->s_sid) {
+                       spp_istat.wrncon++;
+                       goto drop;
+               }
+#endif
+               nsp->nsp_fport =  si->si_sport;
+               cb->s_timer[SPPT_REXMT] = 0;
+               cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
+               soisconnected(so);
+               cb->s_state = TCPS_ESTABLISHED;
+               sppstat.spps_accepts++;

                }
                break;
 
        /*
         * This state means that we have gotten a response
         * to our attempt to establish a connection.
                }
                break;
 
        /*
         * This state means that we have gotten a response
         * to our attempt to establish a connection.

-        * We fill in the data from the other side
-        * (Telling which port to send to instead of the well-
-        * known one we might have to in the first place )
+        * We fill in the data from the other side,
+        * telling us which port to respond to, instead of the well-
+        * known one we might have sent to in the first place.

         * We also require that this is a response to our
         * We also require that this is a response to our

-        * connection id, and that it should be a system packet,
-        * containing no data.
+        * connection id.

         */
        case TCPS_SYN_SENT:
                if (si->si_did!=cb->s_sid) {
                        spp_istat.notme++;
                        goto drop;
                }
         */
        case TCPS_SYN_SENT:
                if (si->si_did!=cb->s_sid) {
                        spp_istat.notme++;
                        goto drop;
                }

+               sppstat.spps_connects++;

                cb->s_did = si->si_sid;
                cb->s_rack = si->si_ack;
                cb->s_ralo = si->si_alo;
                cb->s_dport = nsp->nsp_fport =  si->si_sport;
                cb->s_did = si->si_sid;
                cb->s_rack = si->si_ack;
                cb->s_ralo = si->si_alo;
                cb->s_dport = nsp->nsp_fport =  si->si_sport;

-               cb->s_timer[TCPT_REXMT] = 0;
-               cb->s_flags |= SF_AK;
+               cb->s_timer[SPPT_REXMT] = 0;
+               cb->s_flags |= SF_ACKNOW;

                soisconnected(so);
                cb->s_state = TCPS_ESTABLISHED;
                soisconnected(so);
                cb->s_state = TCPS_ESTABLISHED;

-               break;
-       /*
-        * This state means that we have heard a response
-        * to our acceptance of their connection
-        * It is probably logically unnecessary in this
-        * implementation.
-        */
-        case TCPS_SYN_RECEIVED:
-               if (si->si_did!=cb->s_sid) {
-                       spp_istat.wrncon++;
-                       goto drop;
+               /* Use roundtrip time of connection request for initial rtt */
+               if (cb->s_rtt) {
+                       cb->s_srtt = cb->s_rtt << 3;
+                       cb->s_rttvar = cb->s_rtt << 1;
+                       SPPT_RANGESET(cb->s_rxtcur,
+                           ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
+                           SPPTV_MIN, SPPTV_REXMTMAX);
+                           cb->s_rtt = 0;

                }
                }

-               nsp->nsp_fport =  si->si_sport;
-               cb->s_timer[TCPT_REXMT] = 0;
-               cb->s_timer[TCPT_KEEP] = TCPTV_KEEP;
-               soisconnected(so);
-               cb->s_state = TCPS_ESTABLISHED;

        }
        if (so->so_options & SO_DEBUG || traceallspps)
        }
        if (so->so_options & SO_DEBUG || traceallspps)

-               spp_trace(SA_INPUT, ostate, cb, &spp_savesi, 0);
+               spp_trace(SA_INPUT, (u_char)ostate, cb, &spp_savesi, 0);

 
        m->m_len -= sizeof (struct idp);
 
        m->m_len -= sizeof (struct idp);

-       m->m_off += sizeof (struct idp);
+       m->m_pkthdr.len -= sizeof (struct idp);
+       m->m_data += sizeof (struct idp);

 
 

-       if (spp_reass(cb,si)) {
-               spp_istat.bdreas++;
-               goto drop;
+       if (spp_reass(cb, si)) {
+               (void) m_freem(m);

        }
        }

-       spp_output(cb,(struct mbuf *)0);
+       if (cb->s_force || (cb->s_flags & (SF_ACKNOW|SF_WIN|SF_RXT)))
+               (void) spp_output(cb, (struct mbuf *)0);
+       cb->s_flags &= ~(SF_WIN|SF_RXT);

        return;
 
 dropwithreset:
        return;
 
 dropwithreset:


@@ -197,102 +268,236 @@ dropwithreset:
        si->si_alo = ntohs(si->si_alo);
        ns_error(dtom(si), NS_ERR_NOSOCK, 0);
        if (cb->s_nspcb->nsp_socket->so_options & SO_DEBUG || traceallspps)
        si->si_alo = ntohs(si->si_alo);
        ns_error(dtom(si), NS_ERR_NOSOCK, 0);
        if (cb->s_nspcb->nsp_socket->so_options & SO_DEBUG || traceallspps)

-               spp_trace(SA_DROP, ostate, cb, &spp_savesi, 0);
+               spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);

        return;
 
 drop:
 bad:
        return;
 
 drop:
 bad:

-       if (cb->s_nspcb->nsp_socket->so_options & SO_DEBUG || traceallspps)
-               spp_trace(SA_DROP, ostate, cb, &spp_savesi, 0);
+       if (cb == 0 || cb->s_nspcb->nsp_socket->so_options & SO_DEBUG ||
+            traceallspps)
+               spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);

        m_freem(m);
 }
 
        m_freem(m);
 }
 

+int spprexmtthresh = 3;
+

 /*
  * This is structurally similar to the tcp reassembly routine
  * but its function is somewhat different:  It merely queues
  * packets up, and suppresses duplicates.
  */
 /*
  * This is structurally similar to the tcp reassembly routine
  * but its function is somewhat different:  It merely queues
  * packets up, and suppresses duplicates.
  */

-spp_reass(cb,si)
+spp_reass(cb, si)

 register struct sppcb *cb;
 register struct spidp *si;
 {
        register struct spidp_q *q;
        register struct mbuf *m;
 register struct sppcb *cb;
 register struct spidp *si;
 {
        register struct spidp_q *q;
        register struct mbuf *m;

-       struct socket *so = cb->s_nspcb->nsp_socket;
-       struct sockbuf *sb = & (so->so_rcv);
+       register struct socket *so = cb->s_nspcb->nsp_socket;

        char packetp = cb->s_flags & SF_HI;
        char packetp = cb->s_flags & SF_HI;

+       int incr;

        char wakeup = 0;
 
        char wakeup = 0;
 

-
-       if (si==SI(0))
+       if (si == SI(0))

                goto present;
        /*
         * Update our news from them.
         */
        if (si->si_cc & SP_SA)
                goto present;
        /*
         * Update our news from them.
         */
        if (si->si_cc & SP_SA)

-               cb->s_flags |= SF_DELACK;
-       if (SSEQ_GT(si->si_ack,cb->s_rack)) {
-               cb->s_rack = si->si_ack;
-               cb->s_timer[TCPT_REXMT] = 0;
-
-               /*
-                * If transmit timer is running and timed sequence
-                * number was acked, update smoothed round trip time.
-                */
-               if (cb->s_rtt && SSEQ_GT(si->si_ack, cb->s_rtseq)) {
-                       if (cb->s_srtt == 0)
-                               cb->s_srtt = cb->s_rtt;
-                       else
-                               cb->s_srtt =
-                                   tcp_alpha * cb->s_srtt +
-                                   (1 - tcp_alpha) * cb->s_rtt;
-                       cb->s_rtt = 0;
-               }
+               cb->s_flags |= (spp_use_delack ? SF_DELACK : SF_ACKNOW);
+       if (SSEQ_GT(si->si_alo, cb->s_ralo))
+               cb->s_flags |= SF_WIN;
+       if (SSEQ_LEQ(si->si_ack, cb->s_rack)) {
+               if ((si->si_cc & SP_SP) && cb->s_rack != (cb->s_smax + 1)) {
+                       sppstat.spps_rcvdupack++;
+                       /*
+                        * If this is a completely duplicate ack
+                        * and other conditions hold, we assume
+                        * a packet has been dropped and retransmit
+                        * it exactly as in tcp_input().
+                        */
+                       if (si->si_ack != cb->s_rack ||
+                           si->si_alo != cb->s_ralo)
+                               cb->s_dupacks = 0;
+                       else if (++cb->s_dupacks == spprexmtthresh) {
+                               u_short onxt = cb->s_snxt;
+                               int cwnd = cb->s_cwnd;
+
+                               cb->s_snxt = si->si_ack;
+                               cb->s_cwnd = CUNIT;
+                               cb->s_force = 1 + SPPT_REXMT;
+                               (void) spp_output(cb, (struct mbuf *)0);
+                               cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
+                               cb->s_rtt = 0;
+                               if (cwnd >= 4 * CUNIT)
+                                       cb->s_cwnd = cwnd / 2;
+                               if (SSEQ_GT(onxt, cb->s_snxt))
+                                       cb->s_snxt = onxt;
+                               return (1);
+                       }
+               } else
+                       cb->s_dupacks = 0;
+               goto update_window;

        }
        }

-       if (SSEQ_GT(si->si_alo,cb->s_ralo)) {
-               cb->s_ralo = si->si_alo;
-               cb->s_timer[TCPT_PERSIST] = 0;
+       cb->s_dupacks = 0;
+       /*
+        * If our correspondent acknowledges data we haven't sent
+        * TCP would drop the packet after acking.  We'll be a little
+        * more permissive
+        */
+       if (SSEQ_GT(si->si_ack, (cb->s_smax + 1))) {
+               sppstat.spps_rcvacktoomuch++;
+               si->si_ack = cb->s_smax + 1;

        }
        }

+       sppstat.spps_rcvackpack++;

        /*
        /*

-        * If this is a system packet, we don't need to
-        * queue it up, and won't update acknowledge #
+        * If transmit timer is running and timed sequence
+        * number was acked, update smoothed round trip time.
+        * See discussion of algorithm in tcp_input.c

         */
         */

-       if (si->si_cc & SP_SP)
-               return(0);
-
+       if (cb->s_rtt && SSEQ_GT(si->si_ack, cb->s_rtseq)) {
+               sppstat.spps_rttupdated++;
+               if (cb->s_srtt != 0) {
+                       register short delta;
+                       delta = cb->s_rtt - (cb->s_srtt >> 3);
+                       if ((cb->s_srtt += delta) <= 0)
+                               cb->s_srtt = 1;
+                       if (delta < 0)
+                               delta = -delta;
+                       delta -= (cb->s_rttvar >> 2);
+                       if ((cb->s_rttvar += delta) <= 0)
+                               cb->s_rttvar = 1;
+               } else {
+                       /*
+                        * No rtt measurement yet
+                        */
+                       cb->s_srtt = cb->s_rtt << 3;
+                       cb->s_rttvar = cb->s_rtt << 1;
+               }
+               cb->s_rtt = 0;
+               cb->s_rxtshift = 0;
+               SPPT_RANGESET(cb->s_rxtcur,
+                       ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
+                       SPPTV_MIN, SPPTV_REXMTMAX);
+       }
+       /*
+        * If all outstanding data is acked, stop retransmit
+        * timer and remember to restart (more output or persist).
+        * If there is more data to be acked, restart retransmit
+        * timer, using current (possibly backed-off) value;
+        */
+       if (si->si_ack == cb->s_smax + 1) {
+               cb->s_timer[SPPT_REXMT] = 0;
+               cb->s_flags |= SF_RXT;
+       } else if (cb->s_timer[SPPT_PERSIST] == 0)
+               cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
+       /*
+        * When new data is acked, open the congestion window.
+        * If the window gives us less than ssthresh packets
+        * in flight, open exponentially (maxseg at a time).
+        * Otherwise open linearly (maxseg^2 / cwnd at a time).
+        */
+       incr = CUNIT;
+       if (cb->s_cwnd > cb->s_ssthresh)
+               incr = max(incr * incr / cb->s_cwnd, 1);
+       cb->s_cwnd = min(cb->s_cwnd + incr, cb->s_cwmx);

        /*
        /*

-        * If this packet number has a sequence number less
-        * than that of the first packet not yet seen coming
-        * from them, this must be a duplicate, so drop.
+        * Trim Acked data from output queue.

         */
         */

-       if (SSEQ_LT(si->si_seq,cb->s_ack))
-               return(1);
+       while ((m = so->so_snd.sb_mb) != NULL) {
+               if (SSEQ_LT((mtod(m, struct spidp *))->si_seq, si->si_ack))
+                       sbdroprecord(&so->so_snd);
+               else
+                       break;
+       }
+       sowwakeup(so);
+       cb->s_rack = si->si_ack;
+update_window:
+       if (SSEQ_LT(cb->s_snxt, cb->s_rack))
+               cb->s_snxt = cb->s_rack;
+       if (SSEQ_LT(cb->s_swl1, si->si_seq) || cb->s_swl1 == si->si_seq &&
+           (SSEQ_LT(cb->s_swl2, si->si_ack) ||
+            cb->s_swl2 == si->si_ack && SSEQ_LT(cb->s_ralo, si->si_alo))) {
+               /* keep track of pure window updates */
+               if ((si->si_cc & SP_SP) && cb->s_swl2 == si->si_ack
+                   && SSEQ_LT(cb->s_ralo, si->si_alo)) {
+                       sppstat.spps_rcvwinupd++;
+                       sppstat.spps_rcvdupack--;
+               }
+               cb->s_ralo = si->si_alo;
+               cb->s_swl1 = si->si_seq;
+               cb->s_swl2 = si->si_ack;
+               cb->s_swnd = (1 + si->si_alo - si->si_ack);
+               if (cb->s_swnd > cb->s_smxw)
+                       cb->s_smxw = cb->s_swnd;
+               cb->s_flags |= SF_WIN;
+       }

        /*
         * If this packet number is higher than that which
         * we have allocated refuse it, unless urgent
         */
        /*
         * If this packet number is higher than that which
         * we have allocated refuse it, unless urgent
         */

-       if (SSEQ_GT(si->si_seq,cb->s_alo) && (!(si->si_cc & SP_OB))) {
-               return(1);
+       if (SSEQ_GT(si->si_seq, cb->s_alo)) {
+               if (si->si_cc & SP_SP) {
+                       sppstat.spps_rcvwinprobe++;
+                       return (1);
+               } else
+                       sppstat.spps_rcvpackafterwin++;
+               if (si->si_cc & SP_OB) {
+                       if (SSEQ_GT(si->si_seq, cb->s_alo + 60)) {
+                               ns_error(dtom(si), NS_ERR_FULLUP, 0);
+                               return (0);
+                       } /* else queue this packet; */
+               } else {
+                       /*register struct socket *so = cb->s_nspcb->nsp_socket;
+                       if (so->so_state && SS_NOFDREF) {
+                               ns_error(dtom(si), NS_ERR_NOSOCK, 0);
+                               (void)spp_close(cb);
+                       } else
+                                      would crash system*/
+                       spp_istat.notyet++;
+                       ns_error(dtom(si), NS_ERR_FULLUP, 0);
+                       return (0);
+               }

        }
        /*
        }
        /*

-        * If this packet is urgent, inform process
+        * If this is a system packet, we don't need to
+        * queue it up, and won't update acknowledge #

         */
         */

-       if (si->si_cc & SP_OB) {
-               cb->s_iobc = ((char *)si)[1 + sizeof(*si)];
-               sohasoutofband(so);
+       if (si->si_cc & SP_SP) {
+               return (1);
+       }
+       /*
+        * We have already seen this packet, so drop.
+        */
+       if (SSEQ_LT(si->si_seq, cb->s_ack)) {
+               spp_istat.bdreas++;
+               sppstat.spps_rcvduppack++;
+               if (si->si_seq == cb->s_ack - 1)
+                       spp_istat.lstdup++;
+               return (1);

        }
        }

-

        /*
         * Loop through all packets queued up to insert in
         * appropriate sequence.
         */
        /*
         * Loop through all packets queued up to insert in
         * appropriate sequence.
         */

-

        for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
        for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {

-           if (si->si_seq==SI(q)->si_seq) return(1); /*duplicate */
-           if (SSEQ_LT(si->si_seq,SI(q)->si_seq)) break;
+               if (si->si_seq == SI(q)->si_seq) {
+                       sppstat.spps_rcvduppack++;
+                       return (1);
+               }
+               if (SSEQ_LT(si->si_seq, SI(q)->si_seq)) {
+                       sppstat.spps_rcvoopack++;
+                       break;
+               }
+       }
+       insque(si, q->si_prev);
+       /*
+        * If this packet is urgent, inform process
+        */
+       if (si->si_cc & SP_OB) {
+               cb->s_iobc = ((char *)si)[1 + sizeof(*si)];
+               sohasoutofband(so);
+               cb->s_oobflags |= SF_IOOB;

        }
        }

-       insque(si,q->si_prev);
-               

 present:
 #define SPINC sizeof(struct sphdr)
        /*
 present:
 #define SPINC sizeof(struct sphdr)
        /*


@@ -301,31 +506,72 @@ present:
         * If in packet interface mode, show packet headers.
         */
        for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
         * If in packet interface mode, show packet headers.
         */
        for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {

-                 if (SI(q)->si_seq==cb->s_ack) {
+                 if (SI(q)->si_seq == cb->s_ack) {

                        cb->s_ack++;
                        m = dtom(q);
                        if (SI(q)->si_cc & SP_OB) {
                        cb->s_ack++;
                        m = dtom(q);
                        if (SI(q)->si_cc & SP_OB) {

-                               if (sb->sb_cc)
-                                       so->so_oobmark = sb->sb_cc;
+                               cb->s_oobflags &= ~SF_IOOB;
+                               if (so->so_rcv.sb_cc)
+                                       so->so_oobmark = so->so_rcv.sb_cc;

                                else
                                        so->so_state |= SS_RCVATMARK;
                        }
                        q = q->si_prev;
                        remque(q->si_next);
                        wakeup = 1;
                                else
                                        so->so_state |= SS_RCVATMARK;
                        }
                        q = q->si_prev;
                        remque(q->si_next);
                        wakeup = 1;

+                       sppstat.spps_rcvpack++;
+#ifdef SF_NEWCALL
+                       if (cb->s_flags2 & SF_NEWCALL) {
+                               struct sphdr *sp = mtod(m, struct sphdr *);
+                               u_char dt = sp->sp_dt;
+                               spp_newchecks[4]++;
+                               if (dt != cb->s_rhdr.sp_dt) {
+                                       struct mbuf *mm =
+                                          m_getclr(M_DONTWAIT, MT_CONTROL);
+                                       spp_newchecks[0]++;
+                                       if (mm != NULL) {
+                                               u_short *s =
+                                                       mtod(mm, u_short *);
+                                               cb->s_rhdr.sp_dt = dt;
+                                               mm->m_len = 5; /*XXX*/
+                                               s[0] = 5;
+                                               s[1] = 1;
+                                               *(u_char *)(&s[2]) = dt;
+                                               sbappend(&so->so_rcv, mm);
+                                       }
+                               }
+                               if (sp->sp_cc & SP_OB) {
+                                       MCHTYPE(m, MT_OOBDATA);
+                                       spp_newchecks[1]++;
+                                       so->so_oobmark = 0;
+                                       so->so_state &= ~SS_RCVATMARK;
+                               }
+                               if (packetp == 0) {
+                                       m->m_data += SPINC;
+                                       m->m_len -= SPINC;
+                                       m->m_pkthdr.len -= SPINC;
+                               }
+                               if ((sp->sp_cc & SP_EM) || packetp) {
+                                       sbappendrecord(&so->so_rcv, m);
+                                       spp_newchecks[9]++;
+                               } else
+                                       sbappend(&so->so_rcv, m);
+                       } else
+#endif

                        if (packetp) {
                        if (packetp) {

-                               sbappendrecord(sb,m);
+                               sbappendrecord(&so->so_rcv, m);

                        } else {
                                cb->s_rhdr = *mtod(m, struct sphdr *);
                        } else {
                                cb->s_rhdr = *mtod(m, struct sphdr *);

-                               m->m_off += SPINC;
+                               m->m_data += SPINC;

                                m->m_len -= SPINC;
                                m->m_len -= SPINC;

-                               sbappend(sb,m);
+                               m->m_pkthdr.len -= SPINC;
+                               sbappend(&so->so_rcv, m);

                        }
                  } else
                        break;
        }
        if (wakeup) sorwakeup(so);
                        }
                  } else
                        break;
        }
        if (wakeup) sorwakeup(so);

-       return(0);
+       return (0);

 }
 
 spp_ctlinput(cmd, arg)
 }
 
 spp_ctlinput(cmd, arg)


@@ -334,7 +580,11 @@ spp_ctlinput(cmd, arg)
 {
        struct ns_addr *na;
        extern u_char nsctlerrmap[];
 {
        struct ns_addr *na;
        extern u_char nsctlerrmap[];

-       extern spp_abort();
+       extern spp_abort(), spp_quench();
+       extern struct nspcb *idp_drop();
+       struct ns_errp *errp;
+       struct nspcb *nsp;
+       struct sockaddr_ns *sns;

        int type;
 
        if (cmd < 0 || cmd > PRC_NCMDS)
        int type;
 
        if (cmd < 0 || cmd > PRC_NCMDS)


@@ -342,35 +592,62 @@ spp_ctlinput(cmd, arg)
        type = NS_ERR_UNREACH_HOST;
 
        switch (cmd) {
        type = NS_ERR_UNREACH_HOST;
 
        switch (cmd) {

+

        case PRC_ROUTEDEAD:
        case PRC_ROUTEDEAD:

-       case PRC_QUENCH:
-               break;
+               return;

 
        case PRC_IFDOWN:
 
        case PRC_IFDOWN:

-               na = &((struct sockaddr_ns *)arg)->sns_addr;
-               break;
-

        case PRC_HOSTDEAD:
        case PRC_HOSTUNREACH:
        case PRC_HOSTDEAD:
        case PRC_HOSTUNREACH:

-               na = (struct ns_addr *)arg;
+               sns = (struct sockaddr_ns *)arg;
+               if (sns->sns_family != AF_NS)
+                       return;
+               na = &sns->sns_addr;

                break;
 
        default:
                break;
 
        default:

-               na = &((struct ns_errp *)arg)->ns_err_idp.idp_dna;
-               type = ((struct ns_errp *)arg)->ns_err_num;
-               type = ntohs(type);
+               errp = (struct ns_errp *)arg;
+               na = &errp->ns_err_idp.idp_dna;
+               type = errp->ns_err_num;
+               type = ntohs((u_short)type);

        }
        switch (type) {
        }
        switch (type) {

+

        case NS_ERR_UNREACH_HOST:
        case NS_ERR_UNREACH_HOST:

-       case NS_ERR_NOSOCK:
-               ns_pcbnotify(na, (int)nsctlerrmap[cmd],
-                               spp_abort, (long) 0);
+               ns_pcbnotify(na, (int)nsctlerrmap[cmd], spp_abort, (long) 0);

                break;
                break;

+

        case NS_ERR_TOO_BIG:
        case NS_ERR_TOO_BIG:

-               ns_pcbnotify(na, 0, spp_abort, (long)arg);
+       case NS_ERR_NOSOCK:
+               nsp = ns_pcblookup(na, errp->ns_err_idp.idp_sna.x_port,
+                       NS_WILDCARD);
+               if (nsp) {
+                       if(nsp->nsp_pcb)
+                               (void) spp_drop((struct sppcb *)nsp->nsp_pcb,
+                                               (int)nsctlerrmap[cmd]);
+                       else
+                               (void) idp_drop(nsp, (int)nsctlerrmap[cmd]);
+               }
+               break;
+
+       case NS_ERR_FULLUP:
+               ns_pcbnotify(na, 0, spp_quench, (long) 0);

        }
 }
        }
 }

+/*
+ * When a source quench is received, close congestion window
+ * to one packet.  We will gradually open it again as we proceed.
+ */
+spp_quench(nsp)
+       struct nspcb *nsp;
+{
+       struct sppcb *cb = nstosppcb(nsp);
+
+       if (cb)
+               cb->s_cwnd = CUNIT;
+}

 
 

+#ifdef notdef

 int
 spp_fixmtu(nsp)
 register struct nspcb *nsp;
 int
 spp_fixmtu(nsp)
 register struct nspcb *nsp;


@@ -405,7 +682,7 @@ register struct nspcb *nsp;
                        if (si->si_seq == badseq)
                                break;
                 }
                        if (si->si_seq == badseq)
                                break;
                 }

-                if (m==0) return;
+                if (m == 0) return;

                 firstbad = m;
                 /*for (;;) {*/
                        /* calculate length */
                 firstbad = m;
                 /*for (;;) {*/
                        /* calculate length */


@@ -417,8 +694,8 @@ register struct nspcb *nsp;
                } */
        }
 }
                } */
        }
 }

+#endif

 
 

-int spp_output_cnt = 0;

 spp_output(cb, m0)
        register struct sppcb *cb;
        struct mbuf *m0;
 spp_output(cb, m0)
        register struct sppcb *cb;
        struct mbuf *m0;


@@ -426,41 +703,75 @@ spp_output(cb, m0)
        struct socket *so = cb->s_nspcb->nsp_socket;
        register struct mbuf *m;
        register struct spidp *si = (struct spidp *) 0;
        struct socket *so = cb->s_nspcb->nsp_socket;
        register struct mbuf *m;
        register struct spidp *si = (struct spidp *) 0;

-       register struct sockbuf *sb = &(so->so_snd);
-       register int len = 0;
-       int flags, debit, mtu = cb->s_mtu;
-       int error = 0; u_short lookfor = 0;
+       register struct sockbuf *sb = &so->so_snd;
+       int len = 0, win, rcv_win;
+       short span, off, recordp = 0;
+       u_short alo;
+       int error = 0, sendalot;
+#ifdef notdef
+       int idle;
+#endif

        struct mbuf *mprev;
        extern int idpcksum;
 
        struct mbuf *mprev;
        extern int idpcksum;
 

-       if (m0)
-       {
+       if (m0) {
+               int mtu = cb->s_mtu;
+               int datalen;
+               /*
+                * Make sure that packet isn't too big.
+                */

                for (m = m0; m ; m = m->m_next) {
                        mprev = m;
                        len += m->m_len;
                for (m = m0; m ; m = m->m_next) {
                        mprev = m;
                        len += m->m_len;

+                       if (m->m_flags & M_EOR)
+                               recordp = 1;

                }
                }

-               if (len > mtu) {
+               datalen = (cb->s_flags & SF_HO) ?
+                               len - sizeof (struct sphdr) : len;
+               if (datalen > mtu) {

                        if (cb->s_flags & SF_PI) {
                                m_freem(m0);
                        if (cb->s_flags & SF_PI) {
                                m_freem(m0);

-                               return(EMSGSIZE);
+                               return (EMSGSIZE);

                        } else {
                        } else {

-                               int off = 0;
+                               int oldEM = cb->s_cc & SP_EM;
+
+                               cb->s_cc &= ~SP_EM;

                                while (len > mtu) {
                                while (len > mtu) {

-                                       m = m_copy(m0, off, mtu);
+                                       /*
+                                        * Here we are only being called
+                                        * from usrreq(), so it is OK to
+                                        * block.
+                                        */
+                                       m = m_copym(m0, 0, mtu, M_WAIT);
+                                       if (cb->s_flags & SF_NEWCALL) {
+                                           struct mbuf *mm = m;
+                                           spp_newchecks[7]++;
+                                           while (mm) {
+                                               mm->m_flags &= ~M_EOR;
+                                               mm = mm->m_next;
+                                           }
+                                       }

                                        error = spp_output(cb, m);
                                        if (error) {
                                        error = spp_output(cb, m);
                                        if (error) {

+                                               cb->s_cc |= oldEM;

                                                m_freem(m0);
                                                return(error);
                                        }
                                        m_adj(m0, mtu);
                                        len -= mtu;
                                }
                                                m_freem(m0);
                                                return(error);
                                        }
                                        m_adj(m0, mtu);
                                        len -= mtu;
                                }

+                               cb->s_cc |= oldEM;

                        }
                }
                        }
                }

+               /*
+                * Force length even, by adding a "garbage byte" if
+                * necessary.
+                */

                if (len & 1) {
                if (len & 1) {

-                       if (m->m_len + m->m_off < MMAXOFF) {
+                       m = mprev;
+                       if (M_TRAILINGSPACE(m) >= 1)

                                m->m_len++;
                                m->m_len++;

-                       } else {
+                       else {

                                struct mbuf *m1 = m_get(M_DONTWAIT, MT_DATA);
 
                                if (m1 == 0) {
                                struct mbuf *m1 = m_get(M_DONTWAIT, MT_DATA);
 
                                if (m1 == 0) {


@@ -468,196 +779,355 @@ spp_output(cb, m0)
                                        return (ENOBUFS);
                                }
                                m1->m_len = 1;
                                        return (ENOBUFS);
                                }
                                m1->m_len = 1;

-                               m1->m_off = MMAXOFF - 1;
-                               mprev->m_next = m1;
+                               *(mtod(m1, u_char *)) = 0;
+                               m->m_next = m1;

                        }
                }
                        }
                }

-               m = m_get(M_DONTWAIT, MT_HEADER);
+               m = m_gethdr(M_DONTWAIT, MT_HEADER);

                if (m == 0) {
                        m_freem(m0);
                if (m == 0) {
                        m_freem(m0);

-                       return(ENOBUFS);
+                       return (ENOBUFS);

                }
                }

-

                /*
                 * Fill in mbuf with extended SP header
                 * and addresses and length put into network format.
                 */
                /*
                 * Fill in mbuf with extended SP header
                 * and addresses and length put into network format.
                 */

-               m->m_off = MMAXOFF - sizeof (struct spidp);
+               MH_ALIGN(m, sizeof (struct spidp));

                m->m_len = sizeof (struct spidp);
                m->m_next = m0;
                si = mtod(m, struct spidp *);
                m->m_len = sizeof (struct spidp);
                m->m_next = m0;
                si = mtod(m, struct spidp *);

-               *si = cb->s_shdr;
+               si->si_i = *cb->s_idp;
+               si->si_s = cb->s_shdr;

                if ((cb->s_flags & SF_PI) && (cb->s_flags & SF_HO)) {
                if ((cb->s_flags & SF_PI) && (cb->s_flags & SF_HO)) {

-                       register struct sphdr *sh = mtod(m0, struct sphdr *);
+                       register struct sphdr *sh;
+                       if (m0->m_len < sizeof (*sh)) {
+                               if((m0 = m_pullup(m0, sizeof(*sh))) == NULL) {
+                                       (void) m_free(m);
+                                       m_freem(m0);
+                                       return (EINVAL);
+                               }
+                               m->m_next = m0;
+                       }
+                       sh = mtod(m0, struct sphdr *);

                        si->si_dt = sh->sp_dt;
                        si->si_cc |= sh->sp_cc & SP_EM;
                        m0->m_len -= sizeof (*sh);
                        si->si_dt = sh->sp_dt;
                        si->si_cc |= sh->sp_cc & SP_EM;
                        m0->m_len -= sizeof (*sh);

-                       m0->m_off += sizeof (*sh);
+                       m0->m_data += sizeof (*sh);

                        len -= sizeof (*sh);
                }
                len += sizeof(*si);
                        len -= sizeof (*sh);
                }
                len += sizeof(*si);

-               si->si_len = htons(len);
+               if ((cb->s_flags2 & SF_NEWCALL) && recordp) {
+                       si->si_cc  |= SP_EM;
+                       spp_newchecks[8]++;
+               }
+               if (cb->s_oobflags & SF_SOOB) {
+                       /*
+                        * Per jqj@cornell:
+                        * make sure OB packets convey exactly 1 byte.
+                        * If the packet is 1 byte or larger, we
+                        * have already guaranted there to be at least
+                        * one garbage byte for the checksum, and
+                        * extra bytes shouldn't hurt!
+                        */
+                       if (len > sizeof(*si)) {
+                               si->si_cc |= SP_OB;
+                               len = (1 + sizeof(*si));
+                       }
+               }
+               si->si_len = htons((u_short)len);
+               m->m_pkthdr.len = ((len - 1) | 1) + 1;

                /*
                 * queue stuff up for output
                 */
                /*
                 * queue stuff up for output
                 */

-               sbappendrecord(sb,m);
+               sbappendrecord(sb, m);

                cb->s_seq++;
        }
                cb->s_seq++;
        }

-output:
+#ifdef notdef
+       idle = (cb->s_smax == (cb->s_rack - 1));
+#endif
+again:
+       sendalot = 0;
+       off = cb->s_snxt - cb->s_rack;
+       win = min(cb->s_swnd, (cb->s_cwnd/CUNIT));
+

        /*
        /*

-        * update window
+        * If in persist timeout with window of 0, send a probe.
+        * Otherwise, if window is small but nonzero
+        * and timer expired, send what we can and go into
+        * transmit state.

         */
         */

-       {
-               register struct sockbuf *sb = &so->so_rcv;
-               int credit = ((sb->sb_mbmax - sb->sb_mbcnt) / cb->s_mtu);
-               int alo = cb->s_ack + credit;
+       if (cb->s_force == 1 + SPPT_PERSIST) {
+               if (win != 0) {
+                       cb->s_timer[SPPT_PERSIST] = 0;
+                       cb->s_rxtshift = 0;
+               }
+       }
+       span = cb->s_seq - cb->s_rack;
+       len = min(span, win) - off;

 
 

-               if (cb->s_alo < alo) cb->s_alo = alo;
+       if (len < 0) {
+               /*
+                * Window shrank after we went into it.
+                * If window shrank to 0, cancel pending
+                * restransmission and pull s_snxt back
+                * to (closed) window.  We will enter persist
+                * state below.  If the widndow didn't close completely,
+                * just wait for an ACK.
+                */
+               len = 0;
+               if (win == 0) {
+                       cb->s_timer[SPPT_REXMT] = 0;
+                       cb->s_snxt = cb->s_rack;
+               }

        }
        }

+       if (len > 1)
+               sendalot = 1;
+       rcv_win = sbspace(&so->so_rcv);

 
 

+       /*
+        * Send if we owe peer an ACK.
+        */

        if (cb->s_oobflags & SF_SOOB) {
                /*
                 * must transmit this out of band packet
                 */
                cb->s_oobflags &= ~ SF_SOOB;
        if (cb->s_oobflags & SF_SOOB) {
                /*
                 * must transmit this out of band packet
                 */
                cb->s_oobflags &= ~ SF_SOOB;

-       } else {
-               /*
-                * Decide what to transmit:
-                * If we have a new packet, send that
-                * (So long as it is in our allocation)
-                * If it is time to retransmit a packet,
-                * send that.
-                * Otherwise, see if it time to bang on them
-                * to ask for our current allocation.
-                */
-               if (SSEQ_LT(cb->s_snt, cb->s_ralo))
-                       lookfor = cb->s_snt + 1;
-               else if (cb->s_force==(1+TCPT_REXMT)) {
-                       lookfor = cb->s_rack;
-               } else if (SSEQ_LT(cb->s_ralo, cb->s_seq)) {
-                       lookfor = 0;
-                       if (cb->s_timer[TCPT_PERSIST]==0) {
-                               spp_setpersist(cb);
-                       }
+               sendalot = 1;
+               sppstat.spps_sndurg++;
+               goto found;
+       }
+       if (cb->s_flags & SF_ACKNOW)
+               goto send;
+       if (cb->s_state < TCPS_ESTABLISHED)
+               goto send;
+       /*
+        * Silly window can't happen in spp.
+        * Code from tcp deleted.
+        */
+       if (len)
+               goto send;
+       /*
+        * Compare available window to amount of window
+        * known to peer (as advertised window less
+        * next expected input.)  If the difference is at least two
+        * packets or at least 35% of the mximum possible window,
+        * then want to send a window update to peer.
+        */
+       if (rcv_win > 0) {
+               u_short delta =  1 + cb->s_alo - cb->s_ack;
+               int adv = rcv_win - (delta * cb->s_mtu);
+               
+               if ((so->so_rcv.sb_cc == 0 && adv >= (2 * cb->s_mtu)) ||
+                   (100 * adv / so->so_rcv.sb_hiwat >= 35)) {
+                       sppstat.spps_sndwinup++;
+                       cb->s_flags |= SF_ACKNOW;
+                       goto send;

                }
                }

-               m = sb->sb_mb;
-               while( m ) {
+
+       }
+       /*
+        * Many comments from tcp_output.c are appropriate here
+        * including . . .
+        * If send window is too small, there is data to transmit, and no
+        * retransmit or persist is pending, then go to persist state.
+        * If nothing happens soon, send when timer expires:
+        * if window is nonzero, transmit what we can,
+        * otherwise send a probe.
+        */
+       if (so->so_snd.sb_cc && cb->s_timer[SPPT_REXMT] == 0 &&
+               cb->s_timer[SPPT_PERSIST] == 0) {
+                       cb->s_rxtshift = 0;
+                       spp_setpersist(cb);
+       }
+       /*
+        * No reason to send a packet, just return.
+        */
+       cb->s_outx = 1;
+       return (0);
+
+send:
+       /*
+        * Find requested packet.
+        */
+       si = 0;
+       if (len > 0) {
+               cb->s_want = cb->s_snxt;
+               for (m = sb->sb_mb; m; m = m->m_act) {

                        si = mtod(m, struct spidp *);
                        si = mtod(m, struct spidp *);

-                       m = m->m_act;
-                       if (SSEQ_LT(si->si_seq, cb->s_rack)) {
-                               if ((sb->sb_flags & SB_WAIT)
-                                    || so->so_snd.sb_sel)
-                                        sowwakeup(so);
-                               sbdroprecord(sb);
-                               si = 0;
-                               continue;
-                       } 
-                       if (SSEQ_LT(si->si_seq, lookfor))
-                               continue;
-                       break;
+                       if (SSEQ_LEQ(cb->s_snxt, si->si_seq))
+                               break;
+               }
+       found:
+               if (si) {
+                       if (si->si_seq == cb->s_snxt)
+                                       cb->s_snxt++;
+                               else
+                                       sppstat.spps_sndvoid++, si = 0;

                }
                }

-               if (si && (si->si_seq != lookfor)) si = 0;

        }
        }

-       cb->s_want = lookfor;
+       /*
+        * update window
+        */
+       if (rcv_win < 0)
+               rcv_win = 0;
+       alo = cb->s_ack - 1 + (rcv_win / ((short)cb->s_mtu));
+       if (SSEQ_LT(alo, cb->s_alo)) 
+               alo = cb->s_alo;

 
        if (si) {
                /*
                 * must make a copy of this packet for
                 * idp_output to monkey with
                 */
 
        if (si) {
                /*
                 * must make a copy of this packet for
                 * idp_output to monkey with
                 */

-                m = dtom(si);
-                m0 = m_copy(m, 0, M_COPYALL);
-                m = m0;
-                si = mtod(m, struct spidp *);
-       } else if (cb->s_force || cb->s_flags & SF_AK) {
+               m = m_copy(dtom(si), 0, (int)M_COPYALL);
+               if (m == NULL) {
+                       return (ENOBUFS);
+               }
+               si = mtod(m, struct spidp *);
+               if (SSEQ_LT(si->si_seq, cb->s_smax))
+                       sppstat.spps_sndrexmitpack++;
+               else
+                       sppstat.spps_sndpack++;
+       } else if (cb->s_force || cb->s_flags & SF_ACKNOW) {

                /*
                 * Must send an acknowledgement or a probe
                 */
                /*
                 * Must send an acknowledgement or a probe
                 */

-               m = m_get(M_DONTWAIT, MT_HEADER);
+               if (cb->s_force)
+                       sppstat.spps_sndprobe++;
+               if (cb->s_flags & SF_ACKNOW)
+                       sppstat.spps_sndacks++;
+               m = m_gethdr(M_DONTWAIT, MT_HEADER);

                if (m == 0)
                if (m == 0)

-                       return(ENOBUFS);
+                       return (ENOBUFS);

                /*
                 * Fill in mbuf with extended SP header
                 * and addresses and length put into network format.
                 */
                /*
                 * Fill in mbuf with extended SP header
                 * and addresses and length put into network format.
                 */

-               m->m_off = MMAXOFF - sizeof (struct spidp);
+               MH_ALIGN(m, sizeof (struct spidp));

                m->m_len = sizeof (*si);
                m->m_len = sizeof (*si);

-               m->m_next = 0;
+               m->m_pkthdr.len = sizeof (*si);

                si = mtod(m, struct spidp *);
                si = mtod(m, struct spidp *);

-               *si = cb->s_shdr;
-               si->si_seq = cb->s_snt + 1;
-               len = sizeof (*si);
-               si->si_len = htons((u_short)len);
+               si->si_i = *cb->s_idp;
+               si->si_s = cb->s_shdr;
+               si->si_seq = cb->s_smax + 1;
+               si->si_len = htons(sizeof (*si));

                si->si_cc |= SP_SP;
                si->si_cc |= SP_SP;

-               cb->s_flags &= ~SF_AK;
+       } else {
+               cb->s_outx = 3;
+               if (so->so_options & SO_DEBUG || traceallspps)
+                       spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
+               return (0);

        }
        /*
         * Stuff checksum and output datagram.
         */
        }
        /*
         * Stuff checksum and output datagram.
         */

-       if (si) {
-               /*
-                * If we are almost out of allocation
-                * or one of the timers has gone off
-                * request an ack.
-                */
-               if (SSEQ_GEQ(cb->s_seq,cb->s_ralo))
-                       si->si_cc |= SP_SA;
-               if (cb->s_force) {
-                       si->si_cc |= SP_SA;
-                       cb->s_force = 0;
-               }
-               /* if this is a new packet (and not a system packet)
-                * and we are not currently timing anything
-                * time this one and ask for an ack
-                */
-               if (SSEQ_LT(cb->s_snt,si->si_seq) &&
-                  (!(si->si_cc & SP_SP))) {
-                       cb->s_snt = si->si_seq;
-                       if (cb->s_rtt==0) {
-                               cb->s_rtseq = si->si_seq;
-                               cb->s_rtt = 1;
-                               si->si_cc |= SP_SA;
+       if ((si->si_cc & SP_SP) == 0) {
+               if (cb->s_force != (1 + SPPT_PERSIST) ||
+                   cb->s_timer[SPPT_PERSIST] == 0) {
+                       /*
+                        * If this is a new packet and we are not currently 
+                        * timing anything, time this one.
+                        */
+                       if (SSEQ_LT(cb->s_smax, si->si_seq)) {
+                               cb->s_smax = si->si_seq;
+                               if (cb->s_rtt == 0) {
+                                       sppstat.spps_segstimed++;
+                                       cb->s_rtseq = si->si_seq;
+                                       cb->s_rtt = 1;
+                               }

                        }
                        /*
                        }
                        /*

-                        * If the retransmit timer has not been set
-                        * and this is a real packet
-                        * then start the retransmit timer
+                        * Set rexmt timer if not currently set,
+                        * Initial value for retransmit timer is smoothed
+                        * round-trip time + 2 * round-trip time variance.
+                        * Initialize shift counter which is used for backoff
+                        * of retransmit time.

                         */
                         */

-                       if (cb->s_timer[TCPT_REXMT]==0) {
-                               TCPT_RANGESET(cb->s_timer[TCPT_REXMT],
-                                       tcp_beta * cb->s_srtt, TCPTV_MIN,
-                                       TCPTV_MAX);
-                               cb->s_rxtshift = 0;
+                       if (cb->s_timer[SPPT_REXMT] == 0 &&
+                           cb->s_snxt != cb->s_rack) {
+                               cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
+                               if (cb->s_timer[SPPT_PERSIST]) {
+                                       cb->s_timer[SPPT_PERSIST] = 0;
+                                       cb->s_rxtshift = 0;
+                               }

                        }
                        }

+               } else if (SSEQ_LT(cb->s_smax, si->si_seq)) {
+                       cb->s_smax = si->si_seq;

                }
                }

+       } else if (cb->s_state < TCPS_ESTABLISHED) {
+               if (cb->s_rtt == 0)
+                       cb->s_rtt = 1; /* Time initial handshake */
+               if (cb->s_timer[SPPT_REXMT] == 0)
+                       cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
+       }
+       {
+               /*
+                * Do not request acks when we ack their data packets or
+                * when we do a gratuitous window update.
+                */
+               if (((si->si_cc & SP_SP) == 0) || cb->s_force)
+                               si->si_cc |= SP_SA;

                si->si_seq = htons(si->si_seq);
                si->si_seq = htons(si->si_seq);

-               si->si_alo = htons(cb->s_alo);
+               si->si_alo = htons(alo);

                si->si_ack = htons(cb->s_ack);
 
                if (idpcksum) {
                        si->si_sum = 0;
                si->si_ack = htons(cb->s_ack);
 
                if (idpcksum) {
                        si->si_sum = 0;

-                       len = ((len - 1) | 1) + 1;
-                       si->si_sum = ns_cksum(dtom(si), len);
+                       len = ntohs(si->si_len);
+                       if (len & 1)
+                               len++;
+                       si->si_sum = ns_cksum(m, len);

                } else
                        si->si_sum = 0xffff;
 
                } else
                        si->si_sum = 0xffff;
 

+               cb->s_outx = 4;

                if (so->so_options & SO_DEBUG || traceallspps)
                        spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
                if (so->so_options & SO_DEBUG || traceallspps)
                        spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);

-               spp_output_cnt++;
+

                if (so->so_options & SO_DONTROUTE)
                        error = ns_output(m, (struct route *)0, NS_ROUTETOIF);
                else
                        error = ns_output(m, &cb->s_nspcb->nsp_route, 0);
                if (so->so_options & SO_DONTROUTE)
                        error = ns_output(m, (struct route *)0, NS_ROUTETOIF);
                else
                        error = ns_output(m, &cb->s_nspcb->nsp_route, 0);

-               if (traceallspps && sppconsdebug) {
-                       printf("spp_out: %x\n", error);
-               }
-               return(error);

        }
        }

-       if (so->so_options & SO_DEBUG || traceallspps)
-               spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
-       return(error);
+       if (error) {
+               return (error);
+       }
+       sppstat.spps_sndtotal++;
+       /*
+        * Data sent (as far as we can tell).
+        * If this advertises a larger window than any other segment,
+        * then remember the size of the advertized window.
+        * Any pending ACK has now been sent.
+        */
+       cb->s_force = 0;
+       cb->s_flags &= ~(SF_ACKNOW|SF_DELACK);
+       if (SSEQ_GT(alo, cb->s_alo))
+               cb->s_alo = alo;
+       if (sendalot)
+               goto again;
+       cb->s_outx = 5;
+       return (0);

 }
 
 }
 

+int spp_do_persist_panics = 0;
+
+spp_setpersist(cb)
+       register struct sppcb *cb;
+{
+       register t = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
+       extern int spp_backoff[];
+
+       if (cb->s_timer[SPPT_REXMT] && spp_do_persist_panics)
+               panic("spp_output REXMT");
+       /*
+        * Start/restart persistance timer.
+        */
+       SPPT_RANGESET(cb->s_timer[SPPT_PERSIST],
+           t*spp_backoff[cb->s_rxtshift],
+           SPPTV_PERSMIN, SPPTV_PERSMAX);
+       if (cb->s_rxtshift < SPP_MAXRXTSHIFT)
+               cb->s_rxtshift++;
+}

 /*ARGSUSED*/
 spp_ctloutput(req, so, level, name, value)
        int req;
 /*ARGSUSED*/
 spp_ctloutput(req, so, level, name, value)
        int req;


@@ -673,7 +1143,7 @@ spp_ctloutput(req, so, level, name, value)
        if (level != NSPROTO_SPP) {
                /* This will have to be changed when we do more general
                   stacking of protocols */
        if (level != NSPROTO_SPP) {
                /* This will have to be changed when we do more general
                   stacking of protocols */

-               return(idp_ctloutput(req, so, level, name, value));
+               return (idp_ctloutput(req, so, level, name, value));

        }
        if (nsp == NULL) {
                error = EINVAL;
        }
        if (nsp == NULL) {
                error = EINVAL;


@@ -682,46 +1152,63 @@ spp_ctloutput(req, so, level, name, value)
                cb = nstosppcb(nsp);
 
        switch (req) {
                cb = nstosppcb(nsp);
 
        switch (req) {

+

        case PRCO_GETOPT:
        case PRCO_GETOPT:

-               if (value==NULL) {
-                       error = EINVAL;
-                       goto release;
-               }
+               if (value == NULL)
+                       return (EINVAL);

                m = m_get(M_DONTWAIT, MT_DATA);
                m = m_get(M_DONTWAIT, MT_DATA);

+               if (m == NULL)
+                       return (ENOBUFS);

                switch (name) {
                switch (name) {

+

                case SO_HEADERS_ON_INPUT:
                        mask = SF_HI;
                        goto get_flags;
                case SO_HEADERS_ON_INPUT:
                        mask = SF_HI;
                        goto get_flags;

+

                case SO_HEADERS_ON_OUTPUT:
                        mask = SF_HO;
                get_flags:
                        m->m_len = sizeof(short);
                case SO_HEADERS_ON_OUTPUT:
                        mask = SF_HO;
                get_flags:
                        m->m_len = sizeof(short);

-                       m->m_off = MMAXOFF - sizeof(short);

                        *mtod(m, short *) = cb->s_flags & mask;
                        break;
                        *mtod(m, short *) = cb->s_flags & mask;
                        break;

+
+               case SO_MTU:
+                       m->m_len = sizeof(u_short);
+                       *mtod(m, short *) = cb->s_mtu;
+                       break;
+

                case SO_LAST_HEADER:
                        m->m_len = sizeof(struct sphdr);
                case SO_LAST_HEADER:
                        m->m_len = sizeof(struct sphdr);

-                       m->m_off = MMAXOFF - sizeof(struct sphdr);

                        *mtod(m, struct sphdr *) = cb->s_rhdr;
                        break;
                        *mtod(m, struct sphdr *) = cb->s_rhdr;
                        break;

+

                case SO_DEFAULT_HEADERS:
                        m->m_len = sizeof(struct spidp);
                case SO_DEFAULT_HEADERS:
                        m->m_len = sizeof(struct spidp);

-                       m->m_off = MMAXOFF - sizeof(struct sphdr);
-                       *mtod(m, struct sphdr *) = cb->s_shdr.si_s;
+                       *mtod(m, struct sphdr *) = cb->s_shdr;
+                       break;
+
+               default:
+                       error = EINVAL;

                }
                *value = m;
                break;
                }
                *value = m;
                break;

+

        case PRCO_SETOPT:
        case PRCO_SETOPT:

+               if (value == 0 || *value == 0) {
+                       error = EINVAL;
+                       break;
+               }

                switch (name) {
                switch (name) {

-                       int mask, *ok;
+                       int *ok;

 
                case SO_HEADERS_ON_INPUT:
                        mask = SF_HI;
                        goto set_head;
 
                case SO_HEADERS_ON_INPUT:
                        mask = SF_HI;
                        goto set_head;

+

                case SO_HEADERS_ON_OUTPUT:
                        mask = SF_HO;
                set_head:
                case SO_HEADERS_ON_OUTPUT:
                        mask = SF_HO;
                set_head:

-                       if (value && *value) {
+                       if (cb->s_flags & SF_PI) {

                                ok = mtod(*value, int *);
                                if (*ok)
                                        cb->s_flags |= mask;
                                ok = mtod(*value, int *);
                                if (*ok)
                                        cb->s_flags |= mask;


@@ -729,6 +1216,24 @@ spp_ctloutput(req, so, level, name, value)
                                        cb->s_flags &= ~mask;
                        } else error = EINVAL;
                        break;
                                        cb->s_flags &= ~mask;
                        } else error = EINVAL;
                        break;

+
+               case SO_MTU:
+                       cb->s_mtu = *(mtod(*value, u_short *));
+                       break;
+
+#ifdef SF_NEWCALL
+               case SO_NEWCALL:
+                       ok = mtod(*value, int *);
+                       if (*ok) {
+                               cb->s_flags2 |= SF_NEWCALL;
+                               spp_newchecks[5]++;
+                       } else {
+                               cb->s_flags2 &= ~SF_NEWCALL;
+                               spp_newchecks[6]++;
+                       }
+                       break;
+#endif
+

                case SO_DEFAULT_HEADERS:
                        {
                                register struct sphdr *sp
                case SO_DEFAULT_HEADERS:
                        {
                                register struct sphdr *sp


@@ -736,33 +1241,34 @@ spp_ctloutput(req, so, level, name, value)
                                cb->s_dt = sp->sp_dt;
                                cb->s_cc = sp->sp_cc & SP_EM;
                        }
                                cb->s_dt = sp->sp_dt;
                                cb->s_cc = sp->sp_cc & SP_EM;
                        }

+                       break;
+
+               default:
+                       error = EINVAL;

                }
                }

-               if (value && *value)
-                       m_freem(*value);
+               m_freem(*value);

                break;
        }
        release:
                break;
        }
        release:

-               return(error);
+               return (error);

 }
 
 /*ARGSUSED*/
 }
 
 /*ARGSUSED*/

-spp_usrreq(so, req, m, nam, rights)
+spp_usrreq(so, req, m, nam, controlp)

        struct socket *so;
        int req;
        struct socket *so;
        int req;

-       struct mbuf *m, *nam, *rights;
+       struct mbuf *m, *nam, *controlp;

 {
        struct nspcb *nsp = sotonspcb(so);
        register struct sppcb *cb;
        int s = splnet();
        int error = 0, ostate;
 {
        struct nspcb *nsp = sotonspcb(so);
        register struct sppcb *cb;
        int s = splnet();
        int error = 0, ostate;

+       struct mbuf *mm;
+       register struct sockbuf *sb;

 
        if (req == PRU_CONTROL)
 
        if (req == PRU_CONTROL)

-                return (ns_control(so, (int)m, (caddr_t)nam,
-                       (struct ifnet *)rights));
-       if (rights && rights->m_len) {
-               error = EINVAL;
-               goto release;
-       }
+                return (ns_control(so, m, (caddr_t)nam,
+                       (struct ifnet *)controlp));

        if (nsp == NULL) {
                if (req != PRU_ATTACH) {
                        error = EINVAL;
        if (nsp == NULL) {
                if (req != PRU_ATTACH) {
                        error = EINVAL;


@@ -774,6 +1280,7 @@ spp_usrreq(so, req, m, nam, rights)
        ostate = cb ? cb->s_state : 0;
 
        switch (req) {
        ostate = cb ? cb->s_state : 0;
 
        switch (req) {

+

        case PRU_ATTACH:
                if (nsp != NULL) {
                        error = EISCONN;
        case PRU_ATTACH:
                if (nsp != NULL) {
                        error = EISCONN;


@@ -782,25 +1289,46 @@ spp_usrreq(so, req, m, nam, rights)
                error = ns_pcballoc(so, &nspcb);
                if (error)
                        break;
                error = ns_pcballoc(so, &nspcb);
                if (error)
                        break;

-               error = soreserve(so, 2048, 2048);
-               if (error)
-                       break;
+               if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
+                       error = soreserve(so, (u_long) 3072, (u_long) 3072);
+                       if (error)
+                               break;
+               }

                nsp = sotonspcb(so);
                nsp = sotonspcb(so);

-               {
-                       struct mbuf *mm = m_getclr(M_DONTWAIT,MT_PCB);

 
 

-                       if (mm==NULL) {
-                               error = ENOBUFS;
-                               break;
-                       }
-                       cb = mtod(mm, struct sppcb *);
-                       cb->s_state = TCPS_LISTEN;
-                       cb->s_flags = SF_HI | SF_HO;
-                       cb->s_snt = -1;
-                       cb->s_q.si_next = cb->s_q.si_prev = &cb->s_q;
-                       cb->s_nspcb = nsp;
-                       nsp->nsp_pcb = (caddr_t) cb; 
+               mm = m_getclr(M_DONTWAIT, MT_PCB);
+               sb = &so->so_snd;
+
+               if (mm == NULL) {
+                       error = ENOBUFS;
+                       break;

                }
                }

+               cb = mtod(mm, struct sppcb *);
+               mm = m_getclr(M_DONTWAIT, MT_HEADER);
+               if (mm == NULL) {
+                       (void) m_free(dtom(m));
+                       error = ENOBUFS;
+                       break;
+               }
+               cb->s_idp = mtod(mm, struct idp *);
+               cb->s_state = TCPS_LISTEN;
+               cb->s_smax = -1;
+               cb->s_swl1 = -1;
+               cb->s_q.si_next = cb->s_q.si_prev = &cb->s_q;
+               cb->s_nspcb = nsp;
+               cb->s_mtu = 576 - sizeof (struct spidp);
+               cb->s_cwnd = sbspace(sb) * CUNIT / cb->s_mtu;
+               cb->s_ssthresh = cb->s_cwnd;
+               cb->s_cwmx = sbspace(sb) * CUNIT /
+                               (2 * sizeof (struct spidp));
+               /* Above is recomputed when connecting to account
+                  for changed buffering or mtu's */
+               cb->s_rtt = SPPTV_SRTTBASE;
+               cb->s_rttvar = SPPTV_SRTTDFLT << 2;
+               SPPT_RANGESET(cb->s_rxtcur,
+                   ((SPPTV_SRTTBASE >> 2) + (SPPTV_SRTTDFLT << 2)) >> 1,
+                   SPPTV_MIN, SPPTV_REXMTMAX);
+               nsp->nsp_pcb = (caddr_t) cb; 

                break;
 
        case PRU_DETACH:
                break;
 
        case PRU_DETACH:


@@ -841,11 +1369,12 @@ spp_usrreq(so, req, m, nam, rights)
                if (error)
                        break;
                soisconnecting(so);
                if (error)
                        break;
                soisconnecting(so);

+               sppstat.spps_connattempt++;

                cb->s_state = TCPS_SYN_SENT;
                cb->s_did = 0;
                spp_template(cb);
                cb->s_state = TCPS_SYN_SENT;
                cb->s_did = 0;
                spp_template(cb);

-               cb->s_timer[TCPT_KEEP] = TCPTV_KEEP;
-               cb->s_force = 1 + TCPTV_KEEP;
+               cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
+               cb->s_force = 1 + SPPTV_KEEP;

                /*
                 * Other party is required to respond to
                 * the port I send from, but he is not
                /*
                 * Other party is required to respond to
                 * the port I send from, but he is not


@@ -897,16 +1426,13 @@ spp_usrreq(so, req, m, nam, rights)
         * updating allocation.
         */
        case PRU_RCVD:
         * updating allocation.
         */
        case PRU_RCVD:

+               cb->s_flags |= SF_RVD;

                (void) spp_output(cb, (struct mbuf *) 0);
                (void) spp_output(cb, (struct mbuf *) 0);

-               break;
-
-       case PRU_SEND:
-               error = spp_output(cb, m);
-               m = NULL;
+               cb->s_flags &= ~SF_RVD;

                break;
 
        case PRU_ABORT:
                break;
 
        case PRU_ABORT:

-               spp_drop(cb, ECONNABORTED);
+               (void) spp_drop(cb, ECONNABORTED);

                break;
 
        case PRU_SENSE:
                break;
 
        case PRU_SENSE:


@@ -916,25 +1442,35 @@ spp_usrreq(so, req, m, nam, rights)
                break;
 
        case PRU_RCVOOB:
                break;
 
        case PRU_RCVOOB:

-               if ( ! (cb->s_oobflags & SF_IOOB) ) {
-                       error = EWOULDBLOCK;
+               if ((cb->s_oobflags & SF_IOOB) || so->so_oobmark ||
+                   (so->so_state & SS_RCVATMARK)) {
+                       m->m_len = 1;
+                       *mtod(m, caddr_t) = cb->s_iobc;

                        break;
                }
                        break;
                }

-               m->m_len = 1;
-               *mtod(m, caddr_t) = cb->s_iobc;
-               cb->s_oobflags &= ~ SF_IOOB;
+               error = EINVAL;

                break;
 
        case PRU_SENDOOB:
                if (sbspace(&so->so_snd) < -512) {
                break;
 
        case PRU_SENDOOB:
                if (sbspace(&so->so_snd) < -512) {

-                       m_freem(m);

                        error = ENOBUFS;
                        break;
                }
                cb->s_oobflags |= SF_SOOB;
                        error = ENOBUFS;
                        break;
                }
                cb->s_oobflags |= SF_SOOB;

+               /* fall into */
+       case PRU_SEND:
+               if (controlp) {
+                       u_short *p = mtod(controlp, u_short *);
+                       spp_newchecks[2]++;
+                       if ((p[0] == 5) && p[1] == 1) { /* XXXX, for testing */
+                               cb->s_shdr.sp_dt = *(u_char *)(&p[2]);
+                               spp_newchecks[3]++;
+                       }
+                       m_freem(controlp);
+               }
+               controlp = NULL;

                error = spp_output(cb, m);
                m = NULL;
                error = spp_output(cb, m);
                m = NULL;

-               cb->s_oobflags &= ~SF_SOOB;

                break;
 
        case PRU_SOCKADDR:
                break;
 
        case PRU_SOCKADDR:


@@ -947,6 +1483,7 @@ spp_usrreq(so, req, m, nam, rights)
 
        case PRU_SLOWTIMO:
                cb = spp_timers(cb, (int)nam);
 
        case PRU_SLOWTIMO:
                cb = spp_timers(cb, (int)nam);

+               req |= ((int)nam) << 8;

                break;
 
        case PRU_FASTTIMO:
                break;
 
        case PRU_FASTTIMO:


@@ -959,27 +1496,29 @@ spp_usrreq(so, req, m, nam, rights)
                panic("sp_usrreq");
        }
        if (cb && (so->so_options & SO_DEBUG || traceallspps))
                panic("sp_usrreq");
        }
        if (cb && (so->so_options & SO_DEBUG || traceallspps))

-               spp_trace(SA_USER, ostate, cb, (struct sphdr *)0, req);
+               spp_trace(SA_USER, (u_char)ostate, cb, (struct spidp *)0, req);

 release:
 release:

+       if (controlp != NULL)
+               m_freem(controlp);

        if (m != NULL)
                m_freem(m);
        splx(s);
        return (error);
 }
 
        if (m != NULL)
                m_freem(m);
        splx(s);
        return (error);
 }
 

-spp_usrreq_sp(so, req, m, nam, rights)
+spp_usrreq_sp(so, req, m, nam, controlp)

        struct socket *so;
        int req;
        struct socket *so;
        int req;

-       struct mbuf *m, *nam, *rights;
+       struct mbuf *m, *nam, *controlp;

 {
 {

-       int error = spp_usrreq(so, req, m, nam, rights);
+       int error = spp_usrreq(so, req, m, nam, controlp);

 
 

-       if (req==PRU_ATTACH && error==0) {
+       if (req == PRU_ATTACH && error == 0) {

                struct nspcb *nsp = sotonspcb(so);
                ((struct sppcb *)nsp->nsp_pcb)->s_flags |=
                                        (SF_HI | SF_HO | SF_PI);
        }
                struct nspcb *nsp = sotonspcb(so);
                ((struct sppcb *)nsp->nsp_pcb)->s_flags |=
                                        (SF_HI | SF_HO | SF_PI);
        }

-       return(error);
+       return (error);

 }
 
 /*
 }
 
 /*


@@ -989,18 +1528,24 @@ spp_usrreq_sp(so, req, m, nam, rights)
  * minimizing the amount of work necessary when the connection is used.
  */
 spp_template(cb)
  * minimizing the amount of work necessary when the connection is used.
  */
 spp_template(cb)

-       struct sppcb *cb;
+       register struct sppcb *cb;

 {
        register struct nspcb *nsp = cb->s_nspcb;
 {
        register struct nspcb *nsp = cb->s_nspcb;

-       register struct spidp *n = &(cb->s_shdr);
+       register struct idp *idp = cb->s_idp;
+       register struct sockbuf *sb = &(nsp->nsp_socket->so_snd);

 
 

-       cb->s_mtu = 1024;
-       n->si_pt = NSPROTO_SPP;
-       n->si_sna = nsp->nsp_laddr;
-       n->si_dna = nsp->nsp_faddr;
-       n->si_sid = htons(spp_iss);
+       idp->idp_pt = NSPROTO_SPP;
+       idp->idp_sna = nsp->nsp_laddr;
+       idp->idp_dna = nsp->nsp_faddr;
+       cb->s_sid = htons(spp_iss);

        spp_iss += SPP_ISSINCR/2;
        spp_iss += SPP_ISSINCR/2;

-       n->si_alo = 1;
+       cb->s_alo = 1;
+       cb->s_cwnd = (sbspace(sb) * CUNIT) / cb->s_mtu;
+       cb->s_ssthresh = cb->s_cwnd; /* Try to expand fast to full complement
+                                       of large packets */
+       cb->s_cwmx = (sbspace(sb) * CUNIT) / (2 * sizeof(struct spidp));
+       cb->s_cwmx = max(cb->s_cwmx, cb->s_cwnd);
+               /* But allow for lots of little packets as well */

 }
 
 /*
 }
 
 /*


@@ -1025,11 +1570,13 @@ spp_close(cb)
                remque(s->si_prev);
                m_freem(m);
        }
                remque(s->si_prev);
                m_freem(m);
        }

+       (void) m_free(dtom(cb->s_idp));

        (void) m_free(dtom(cb));
        nsp->nsp_pcb = 0;
        soisdisconnected(so);
        ns_pcbdetach(nsp);
        (void) m_free(dtom(cb));
        nsp->nsp_pcb = 0;
        soisdisconnected(so);
        ns_pcbdetach(nsp);

-       return((struct sppcb *)0);
+       sppstat.spps_closed++;
+       return ((struct sppcb *)0);

 }
 /*
  *     Someday we may do level 3 handshaking
 }
 /*
  *     Someday we may do level 3 handshaking


@@ -1040,13 +1587,13 @@ struct sppcb *
 spp_usrclosed(cb)
        register struct sppcb *cb;
 {
 spp_usrclosed(cb)
        register struct sppcb *cb;
 {

-       return(spp_close(cb));
+       return (spp_close(cb));

 }
 struct sppcb *
 spp_disconnect(cb)
        register struct sppcb *cb;
 {
 }
 struct sppcb *
 spp_disconnect(cb)
        register struct sppcb *cb;
 {

-       return(spp_close(cb));
+       return (spp_close(cb));

 }
 /*
  * Drop connection, reporting
 }
 /*
  * Drop connection, reporting


@@ -1064,10 +1611,12 @@ spp_drop(cb, errno)
         * we will generate error protocol packets
         * announcing that the socket has gone away.
         */
         * we will generate error protocol packets
         * announcing that the socket has gone away.
         */

-       /*if (TCPS_HAVERCVDSYN(tp->t_state)) {
-               tp->t_state = TCPS_CLOSED;
-               (void) tcp_output(tp);
-       }*/
+       if (TCPS_HAVERCVDSYN(cb->s_state)) {
+               sppstat.spps_drops++;
+               cb->s_state = TCPS_CLOSED;
+               /*(void) tcp_output(cb);*/
+       } else
+               sppstat.spps_conndrops++;

        so->so_error = errno;
        return (spp_close(cb));
 }
        so->so_error = errno;
        return (spp_close(cb));
 }


@@ -1076,29 +1625,14 @@ spp_abort(nsp)
        struct nspcb *nsp;
 {
 
        struct nspcb *nsp;
 {
 

-       spp_close((struct sppcb *)nsp->nsp_pcb);
+       (void) spp_close((struct sppcb *)nsp->nsp_pcb);

 }
 
 }
 

-spp_setpersist(cb)
-       register struct sppcb *cb;
-{
-
-       /*if (cb->s_timer[TCPT_REXMT])
-               panic("spp_output REXMT");*/
-       /*
-        * Start/restart persistance timer.
-        */
-       TCPT_RANGESET(cb->s_timer[TCPT_PERSIST],
-           ((int)(tcp_beta * cb->s_srtt)) << cb->s_rxtshift,
-           TCPTV_PERSMIN, TCPTV_MAX);
-       cb->s_rxtshift++;
-       if (cb->s_rxtshift >= TCP_MAXRXTSHIFT)
-               cb->s_rxtshift = 0;
-}
+int    spp_backoff[SPP_MAXRXTSHIFT+1] =
+    { 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 };

 /*
  * Fast timeout routine for processing delayed acks
  */
 /*
  * Fast timeout routine for processing delayed acks
  */

-int spp_ftcnt;

 spp_fasttimo()
 {
        register struct nspcb *nsp;
 spp_fasttimo()
 {
        register struct nspcb *nsp;


@@ -1106,13 +1640,13 @@ spp_fasttimo()
        int s = splnet();
 
        nsp = nspcb.nsp_next;
        int s = splnet();
 
        nsp = nspcb.nsp_next;

-       spp_ftcnt++;

        if (nsp)
        for (; nsp != &nspcb; nsp = nsp->nsp_next)
                if ((cb = (struct sppcb *)nsp->nsp_pcb) &&
                    (cb->s_flags & SF_DELACK)) {
                        cb->s_flags &= ~SF_DELACK;
        if (nsp)
        for (; nsp != &nspcb; nsp = nsp->nsp_next)
                if ((cb = (struct sppcb *)nsp->nsp_pcb) &&
                    (cb->s_flags & SF_DELACK)) {
                        cb->s_flags &= ~SF_DELACK;

-                       cb->s_flags |= SF_AK;
+                       cb->s_flags |= SF_ACKNOW;
+                       sppstat.spps_delack++;

                        (void) spp_output(cb, (struct mbuf *) 0);
                }
        splx(s);
                        (void) spp_output(cb, (struct mbuf *) 0);
                }
        splx(s);


@@ -1143,11 +1677,12 @@ spp_slowtimo()
                ipnxt = ip->nsp_next;
                if (cb == 0)
                        goto tpgone;
                ipnxt = ip->nsp_next;
                if (cb == 0)
                        goto tpgone;

-               for (i = 0; i < TCPT_NTIMERS; i++) {
+               for (i = 0; i < SPPT_NTIMERS; i++) {

                        if (cb->s_timer[i] && --cb->s_timer[i] == 0) {
                                (void) spp_usrreq(cb->s_nspcb->nsp_socket,
                                    PRU_SLOWTIMO, (struct mbuf *)0,
                        if (cb->s_timer[i] && --cb->s_timer[i] == 0) {
                                (void) spp_usrreq(cb->s_nspcb->nsp_socket,
                                    PRU_SLOWTIMO, (struct mbuf *)0,

-                                   (struct mbuf *)i, (struct mbuf *)0);
+                                   (struct mbuf *)i, (struct mbuf *)0,
+                                   (struct mbuf *)0);

                                if (ipnxt->nsp_prev != ip)
                                        goto tpgone;
                        }
                                if (ipnxt->nsp_prev != ip)
                                        goto tpgone;
                        }


@@ -1161,84 +1696,109 @@ tpgone:
        spp_iss += SPP_ISSINCR/PR_SLOWHZ;               /* increment iss */
        splx(s);
 }
        spp_iss += SPP_ISSINCR/PR_SLOWHZ;               /* increment iss */
        splx(s);
 }

-
-float  spp_backoff[TCP_MAXRXTSHIFT] =
-    { 1.0, 1.2, 1.4, 1.7, 2.0, 3.0, 5.0, 8.0, 16.0, 32.0 };
-extern int tcpexprexmtbackoff;

 /*
 /*

- * TCP timer processing.
+ * SPP timer processing.

  */
 struct sppcb *
 spp_timers(cb, timer)
        register struct sppcb *cb;
        int timer;
 {
  */
 struct sppcb *
 spp_timers(cb, timer)
        register struct sppcb *cb;
        int timer;
 {

+       long rexmt;
+       int win;

 
        cb->s_force = 1 + timer;
        switch (timer) {
 
        /*
 
        cb->s_force = 1 + timer;
        switch (timer) {
 
        /*

-        * 2 MSL timeout in shutdown went off.  Delete connection
+        * 2 MSL timeout in shutdown went off.  TCP deletes connection

         * control block.
         */
         * control block.
         */

-       case TCPT_2MSL:
-               cb = spp_close(cb);
+       case SPPT_2MSL:
+               printf("spp: SPPT_2MSL went off for no reason\n");
+               cb->s_timer[timer] = 0;

                break;
 
        /*
         * Retransmission timer went off.  Message has not
         * been acked within retransmit interval.  Back off
                break;
 
        /*
         * Retransmission timer went off.  Message has not
         * been acked within retransmit interval.  Back off

-        * to a longer retransmit interval and retransmit all
-        * unacknowledged messages in the window.
+        * to a longer retransmit interval and retransmit one packet.

         */
         */

-       case TCPT_REXMT:
-               cb->s_rxtshift++;
-               if (cb->s_rxtshift > TCP_MAXRXTSHIFT) {
+       case SPPT_REXMT:
+               if (++cb->s_rxtshift > SPP_MAXRXTSHIFT) {
+                       cb->s_rxtshift = SPP_MAXRXTSHIFT;
+                       sppstat.spps_timeoutdrop++;

                        cb = spp_drop(cb, ETIMEDOUT);
                        break;
                }
                        cb = spp_drop(cb, ETIMEDOUT);
                        break;
                }

-               (void) spp_output(cb, (struct mbuf *) 0);
-               TCPT_RANGESET(cb->s_timer[TCPT_REXMT],
-                   (int)cb->s_srtt, TCPTV_MIN, TCPTV_MAX);
-               if (tcpexprexmtbackoff) {
-                       TCPT_RANGESET(cb->s_timer[TCPT_REXMT],
-                           cb->s_timer[TCPT_REXMT] << cb->s_rxtshift,
-                           TCPTV_MIN, TCPTV_MAX);
-               } else {
-                       TCPT_RANGESET(cb->s_timer[TCPT_REXMT],
-                           cb->s_timer[TCPT_REXMT] *
-                               spp_backoff[cb->s_rxtshift - 1],
-                           TCPTV_MIN, TCPTV_MAX);
+               sppstat.spps_rexmttimeo++;
+               rexmt = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
+               rexmt *= spp_backoff[cb->s_rxtshift];
+               SPPT_RANGESET(cb->s_rxtcur, rexmt, SPPTV_MIN, SPPTV_REXMTMAX);
+               cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
+               /*
+                * If we have backed off fairly far, our srtt
+                * estimate is probably bogus.  Clobber it
+                * so we'll take the next rtt measurement as our srtt;
+                * move the current srtt into rttvar to keep the current
+                * retransmit times until then.
+                */
+               if (cb->s_rxtshift > SPP_MAXRXTSHIFT / 4 ) {
+                       cb->s_rttvar += (cb->s_srtt >> 2);
+                       cb->s_srtt = 0;

                }
                }

+               cb->s_snxt = cb->s_rack;
+               /*
+                * If timing a packet, stop the timer.
+                */
+               cb->s_rtt = 0;
+               /*
+                * See very long discussion in tcp_timer.c about congestion
+                * window and sstrhesh
+                */
+               win = min(cb->s_swnd, (cb->s_cwnd/CUNIT)) / 2;
+               if (win < 2)
+                       win = 2;
+               cb->s_cwnd = CUNIT;
+               cb->s_ssthresh = win * CUNIT;
+               (void) spp_output(cb, (struct mbuf *) 0);

                break;
 
        /*
         * Persistance timer into zero window.
         * Force a probe to be sent.
         */
                break;
 
        /*
         * Persistance timer into zero window.
         * Force a probe to be sent.
         */

-       case TCPT_PERSIST:
-               (void) spp_output(cb, (struct mbuf *) 0);
+       case SPPT_PERSIST:
+               sppstat.spps_persisttimeo++;

                spp_setpersist(cb);
                spp_setpersist(cb);

+               (void) spp_output(cb, (struct mbuf *) 0);

                break;
 
        /*
         * Keep-alive timer went off; send something
         * or drop connection if idle for too long.
         */
                break;
 
        /*
         * Keep-alive timer went off; send something
         * or drop connection if idle for too long.
         */

-       case TCPT_KEEP:
+       case SPPT_KEEP:
+               sppstat.spps_keeptimeo++;

                if (cb->s_state < TCPS_ESTABLISHED)
                        goto dropit;
                if (cb->s_nspcb->nsp_socket->so_options & SO_KEEPALIVE) {
                if (cb->s_state < TCPS_ESTABLISHED)
                        goto dropit;
                if (cb->s_nspcb->nsp_socket->so_options & SO_KEEPALIVE) {

-                       if (cb->s_idle >= TCPTV_MAXIDLE)
+                       if (cb->s_idle >= SPPTV_MAXIDLE)

                                goto dropit;
                                goto dropit;

+                       sppstat.spps_keepprobe++;

                        (void) spp_output(cb, (struct mbuf *) 0);
                } else
                        cb->s_idle = 0;
                        (void) spp_output(cb, (struct mbuf *) 0);
                } else
                        cb->s_idle = 0;

-               cb->s_timer[TCPT_KEEP] = TCPTV_KEEP;
+               cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;

                break;
        dropit:
                break;
        dropit:

+               sppstat.spps_keepdrops++;

                cb = spp_drop(cb, ETIMEDOUT);
                break;
        }
        return (cb);
 }
                cb = spp_drop(cb, ETIMEDOUT);
                break;
        }
        return (cb);
 }

+#ifndef lint
+int SppcbSize = sizeof (struct sppcb);
+int NspcbSize = sizeof (struct nspcb);
+#endif /* lint */