sys/netproto/ns/spp_usrreq.c

   1 /*
   2  * Copyright (c) 1984, 1985, 1986, 1987, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)spp_usrreq.c        8.1 (Berkeley) 6/10/93
  34  * $FreeBSD: src/sys/netns/spp_usrreq.c,v 1.11 1999/08/28 00:49:53 peter Exp $
  35  * $DragonFly: src/sys/netproto/ns/spp_usrreq.c,v 1.22 2007/04/22 01:13:16 dillon Exp $
  36  */
  37
  38 #include <sys/param.h>
  39 #include <sys/systm.h>
  40 #include <sys/kernel.h>
  41 #include <sys/malloc.h>
  42 #include <sys/mbuf.h>
  43 #include <sys/protosw.h>
  44 #include <sys/socket.h>
  45 #include <sys/socketvar.h>
  46 #include <sys/errno.h>
  47 #include <sys/thread2.h>
  48
  49 #include <net/if.h>
  50 #include <net/route.h>
  51 #include <netinet/tcp_fsm.h>
  52
  53 #include "ns.h"
  54 #include "ns_pcb.h"
  55 #include "idp.h"
  56 #include "idp_var.h"
  57 #include "ns_error.h"
  58 #include "sp.h"
  59 #include "spidp.h"
  60 #include "spp_timer.h"
  61 #include "spp_var.h"
  62 #include "spp_debug.h"
  63
  64 extern u_char nsctlerrmap[];            /* from ns_input.c */
  65 extern int idpcksum;                    /* from ns_input.c */
  66
  67 static MALLOC_DEFINE(M_IDP, "ns_idp", "NS Packet Management");
  68 static MALLOC_DEFINE(M_SPIDP_Q, "ns_spidp_q", "NS Packet Management");
  69 static MALLOC_DEFINE(M_SPPCB, "ns_sppcb", "NS PCB Management");
  70
  71 struct spp_istat spp_istat;
  72 u_short spp_iss;
  73 int     spp_backoff[SPP_MAXRXTSHIFT+1] =
  74     { 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 };
  75
  76 /*
  77  * SP protocol implementation.
  78  */
  79 void
  80 spp_init(void)
  81 {
  82         spp_iss = 1; /* WRONG !! should fish it out of TODR */
  83 }
  84 struct spidp spp_savesi;
  85 int traceallspps = 0;
  86 extern int sppconsdebug;
  87 int spp_hardnosed;
  88 int spp_use_delack = 0;
  89 u_short spp_newchecks[50];
  90
  91 /*ARGSUSED*/
  92 void
  93 spp_input(struct mbuf *m, ...)
  94 {
  95         struct sppcb *cb;
  96         struct spidp *si;
  97         struct socket *so;
  98         short ostate = 0;
  99         int dropsocket = 0;
 100         struct nspcb *nsp;
 101         __va_list ap;
 102
 103         __va_start(ap, m);
 104         nsp = __va_arg(ap, struct nspcb *);
 105         __va_end(ap);
 106
 107         sppstat.spps_rcvtotal++;
 108         if (nsp == 0) {
 109                 panic("No nspcb in spp_input");
 110                 return;
 111         }
 112
 113         cb = nstosppcb(nsp);
 114         if (cb == 0) goto bad;
 115
 116         if (m->m_len < sizeof(struct spidp)) {
 117                 if ((m = m_pullup(m, sizeof(*si))) == 0) {
 118                         sppstat.spps_rcvshort++;
 119                         return;
 120                 }
 121         }
 122         si = mtod(m, struct spidp *);
 123         si->si_seq = ntohs(si->si_seq);
 124         si->si_ack = ntohs(si->si_ack);
 125         si->si_alo = ntohs(si->si_alo);
 126
 127         so = nsp->nsp_socket;
 128         if (so->so_options & SO_DEBUG || traceallspps) {
 129                 ostate = cb->s_state;
 130                 spp_savesi = *si;
 131         }
 132         if (so->so_options & SO_ACCEPTCONN) {
 133                 struct sppcb *ocb = cb;
 134
 135                 so = sonewconn(so, 0);
 136                 if (so == 0) {
 137                         goto drop;
 138                 }
 139                 /*
 140                  * This is ugly, but ....
 141                  *
 142                  * Mark socket as temporary until we're
 143                  * committed to keeping it.  The code at
 144                  * ``drop'' and ``dropwithreset'' check the
 145                  * flag dropsocket to see if the temporary
 146                  * socket created here should be discarded.
 147                  * We mark the socket as discardable until
 148                  * we're committed to it below in TCPS_LISTEN.
 149                  */
 150                 dropsocket++;
 151                 nsp = (struct nspcb *)so->so_pcb;
 152                 nsp->nsp_laddr = si->si_dna;
 153                 cb = nstosppcb(nsp);
 154                 cb->s_mtu = ocb->s_mtu;         /* preserve sockopts */
 155                 cb->s_flags = ocb->s_flags;     /* preserve sockopts */
 156                 cb->s_flags2 = ocb->s_flags2;   /* preserve sockopts */
 157                 cb->s_state = TCPS_LISTEN;
 158         }
 159
 160         /*
 161          * Packet received on connection.
 162          * reset idle time and keep-alive timer;
 163          */
 164         cb->s_idle = 0;
 165         cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
 166
 167         switch (cb->s_state) {
 168
 169         case TCPS_LISTEN:{
 170                 struct mbuf *am;
 171                 struct sockaddr_ns *sns;
 172                 struct ns_addr laddr;
 173
 174                 /*
 175                  * If somebody here was carying on a conversation
 176                  * and went away, and his pen pal thinks he can
 177                  * still talk, we get the misdirected packet.
 178                  */
 179                 if (spp_hardnosed && (si->si_did != 0 || si->si_seq != 0)) {
 180                         spp_istat.gonawy++;
 181                         goto dropwithreset;
 182                 }
 183                 am = m_get(MB_DONTWAIT, MT_SONAME);
 184                 if (am == NULL)
 185                         goto drop;
 186                 am->m_len = sizeof (struct sockaddr_ns);
 187                 sns = mtod(am, struct sockaddr_ns *);
 188                 sns->sns_len = sizeof(*sns);
 189                 sns->sns_family = AF_NS;
 190                 sns->sns_addr = si->si_sna;
 191                 laddr = nsp->nsp_laddr;
 192                 if (ns_nullhost(laddr))
 193                         nsp->nsp_laddr = si->si_dna;
 194                 if (ns_pcbconnect(nsp, mtod(am, struct sockaddr *))) {
 195                         nsp->nsp_laddr = laddr;
 196                         m_free(am);
 197                         spp_istat.noconn++;
 198                         goto drop;
 199                 }
 200                 m_free(am);
 201                 spp_template(cb);
 202                 dropsocket = 0;         /* committed to socket */
 203                 cb->s_did = si->si_sid;
 204                 cb->s_rack = si->si_ack;
 205                 cb->s_ralo = si->si_alo;
 206 #define THREEWAYSHAKE
 207 #ifdef THREEWAYSHAKE
 208                 cb->s_state = TCPS_SYN_RECEIVED;
 209                 cb->s_force = 1 + SPPT_KEEP;
 210                 sppstat.spps_accepts++;
 211                 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
 212                 }
 213                 break;
 214         /*
 215          * This state means that we have heard a response
 216          * to our acceptance of their connection
 217          * It is probably logically unnecessary in this
 218          * implementation.
 219          */
 220          case TCPS_SYN_RECEIVED: {
 221                 if (si->si_did!=cb->s_sid) {
 222                         spp_istat.wrncon++;
 223                         goto drop;
 224                 }
 225 #endif
 226                 nsp->nsp_fport =  si->si_sport;
 227                 cb->s_timer[SPPT_REXMT] = 0;
 228                 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
 229                 soisconnected(so);
 230                 cb->s_state = TCPS_ESTABLISHED;
 231                 sppstat.spps_accepts++;
 232                 }
 233                 break;
 234
 235         /*
 236          * This state means that we have gotten a response
 237          * to our attempt to establish a connection.
 238          * We fill in the data from the other side,
 239          * telling us which port to respond to, instead of the well-
 240          * known one we might have sent to in the first place.
 241          * We also require that this is a response to our
 242          * connection id.
 243          */
 244         case TCPS_SYN_SENT:
 245                 if (si->si_did!=cb->s_sid) {
 246                         spp_istat.notme++;
 247                         goto drop;
 248                 }
 249                 sppstat.spps_connects++;
 250                 cb->s_did = si->si_sid;
 251                 cb->s_rack = si->si_ack;
 252                 cb->s_ralo = si->si_alo;
 253                 cb->s_dport = nsp->nsp_fport =  si->si_sport;
 254                 cb->s_timer[SPPT_REXMT] = 0;
 255                 cb->s_flags |= SF_ACKNOW;
 256                 soisconnected(so);
 257                 cb->s_state = TCPS_ESTABLISHED;
 258                 /* Use roundtrip time of connection request for initial rtt */
 259                 if (cb->s_rtt) {
 260                         cb->s_srtt = cb->s_rtt << 3;
 261                         cb->s_rttvar = cb->s_rtt << 1;
 262                         SPPT_RANGESET(cb->s_rxtcur,
 263                             ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
 264                             SPPTV_MIN, SPPTV_REXMTMAX);
 265                             cb->s_rtt = 0;
 266                 }
 267         }
 268         if (so->so_options & SO_DEBUG || traceallspps)
 269                 spp_trace(SA_INPUT, (u_char)ostate, cb, &spp_savesi, 0);
 270
 271         m->m_len -= sizeof (struct idp);
 272         m->m_pkthdr.len -= sizeof (struct idp);
 273         m->m_data += sizeof (struct idp);
 274
 275         if (spp_reass(cb, si, m)) {
 276                 m_freem(m);
 277         }
 278         if (cb->s_force || (cb->s_flags & (SF_ACKNOW|SF_WIN|SF_RXT)))
 279                 spp_output(cb, (struct mbuf *)0);
 280         cb->s_flags &= ~(SF_WIN|SF_RXT);
 281         return;
 282
 283 dropwithreset:
 284         if (dropsocket)
 285                 soabort(so);
 286         si->si_seq = ntohs(si->si_seq);
 287         si->si_ack = ntohs(si->si_ack);
 288         si->si_alo = ntohs(si->si_alo);
 289         ns_error(m, NS_ERR_NOSOCK, 0);
 290         if (cb->s_nspcb->nsp_socket->so_options & SO_DEBUG || traceallspps)
 291                 spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);
 292         return;
 293
 294 drop:
 295 bad:
 296         if (cb == 0 || cb->s_nspcb->nsp_socket->so_options & SO_DEBUG ||
 297             traceallspps)
 298                 spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);
 299         m_freem(m);
 300 }
 301
 302 int spprexmtthresh = 3;
 303
 304 /*
 305  * This is structurally similar to the tcp reassembly routine
 306  * but its function is somewhat different:  It merely queues
 307  * packets up, and suppresses duplicates.
 308  */
 309 int
 310 spp_reass(struct sppcb *cb, struct spidp *si, struct mbuf *si_m)
 311 {
 312         struct spidp_q *q;
 313         struct spidp_q *nq;
 314         struct mbuf *m;
 315         struct socket *so = cb->s_nspcb->nsp_socket;
 316         char packetp = cb->s_flags & SF_HI;
 317         int incr;
 318         char wakeup = 0;
 319
 320         if (si == NULL)
 321                 goto present;
 322         /*
 323          * Update our news from them.
 324          */
 325         if (si->si_cc & SP_SA)
 326                 cb->s_flags |= (spp_use_delack ? SF_DELACK : SF_ACKNOW);
 327         if (SSEQ_GT(si->si_alo, cb->s_ralo))
 328                 cb->s_flags |= SF_WIN;
 329         if (SSEQ_LEQ(si->si_ack, cb->s_rack)) {
 330                 if ((si->si_cc & SP_SP) && cb->s_rack != (cb->s_smax + 1)) {
 331                         sppstat.spps_rcvdupack++;
 332                         /*
 333                          * If this is a completely duplicate ack
 334                          * and other conditions hold, we assume
 335                          * a packet has been dropped and retransmit
 336                          * it exactly as in tcp_input().
 337                          */
 338                         if (si->si_ack != cb->s_rack ||
 339                             si->si_alo != cb->s_ralo)
 340                                 cb->s_dupacks = 0;
 341                         else if (++cb->s_dupacks == spprexmtthresh) {
 342                                 u_short onxt = cb->s_snxt;
 343                                 int cwnd = cb->s_cwnd;
 344
 345                                 cb->s_snxt = si->si_ack;
 346                                 cb->s_cwnd = CUNIT;
 347                                 cb->s_force = 1 + SPPT_REXMT;
 348                                 spp_output(cb, (struct mbuf *)0);
 349                                 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
 350                                 cb->s_rtt = 0;
 351                                 if (cwnd >= 4 * CUNIT)
 352                                         cb->s_cwnd = cwnd / 2;
 353                                 if (SSEQ_GT(onxt, cb->s_snxt))
 354                                         cb->s_snxt = onxt;
 355                                 return (1);
 356                         }
 357                 } else
 358                         cb->s_dupacks = 0;
 359                 goto update_window;
 360         }
 361         cb->s_dupacks = 0;
 362         /*
 363          * If our correspondent acknowledges data we haven't sent
 364          * TCP would drop the packet after acking.  We'll be a little
 365          * more permissive
 366          */
 367         if (SSEQ_GT(si->si_ack, (cb->s_smax + 1))) {
 368                 sppstat.spps_rcvacktoomuch++;
 369                 si->si_ack = cb->s_smax + 1;
 370         }
 371         sppstat.spps_rcvackpack++;
 372         /*
 373          * If transmit timer is running and timed sequence
 374          * number was acked, update smoothed round trip time.
 375          * See discussion of algorithm in tcp_input.c
 376          */
 377         if (cb->s_rtt && SSEQ_GT(si->si_ack, cb->s_rtseq)) {
 378                 sppstat.spps_rttupdated++;
 379                 if (cb->s_srtt != 0) {
 380                         short delta;
 381                         delta = cb->s_rtt - (cb->s_srtt >> 3);
 382                         if ((cb->s_srtt += delta) <= 0)
 383                                 cb->s_srtt = 1;
 384                         if (delta < 0)
 385                                 delta = -delta;
 386                         delta -= (cb->s_rttvar >> 2);
 387                         if ((cb->s_rttvar += delta) <= 0)
 388                                 cb->s_rttvar = 1;
 389                 } else {
 390                         /*
 391                          * No rtt measurement yet
 392                          */
 393                         cb->s_srtt = cb->s_rtt << 3;
 394                         cb->s_rttvar = cb->s_rtt << 1;
 395                 }
 396                 cb->s_rtt = 0;
 397                 cb->s_rxtshift = 0;
 398                 SPPT_RANGESET(cb->s_rxtcur,
 399                         ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
 400                         SPPTV_MIN, SPPTV_REXMTMAX);
 401         }
 402         /*
 403          * If all outstanding data is acked, stop retransmit
 404          * timer and remember to restart (more output or persist).
 405          * If there is more data to be acked, restart retransmit
 406          * timer, using current (possibly backed-off) value;
 407          */
 408         if (si->si_ack == cb->s_smax + 1) {
 409                 cb->s_timer[SPPT_REXMT] = 0;
 410                 cb->s_flags |= SF_RXT;
 411         } else if (cb->s_timer[SPPT_PERSIST] == 0)
 412                 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
 413         /*
 414          * When new data is acked, open the congestion window.
 415          * If the window gives us less than ssthresh packets
 416          * in flight, open exponentially (maxseg at a time).
 417          * Otherwise open linearly (maxseg^2 / cwnd at a time).
 418          */
 419         incr = CUNIT;
 420         if (cb->s_cwnd > cb->s_ssthresh)
 421                 incr = max(incr * incr / cb->s_cwnd, 1);
 422         cb->s_cwnd = min(cb->s_cwnd + incr, cb->s_cwmx);
 423         /*
 424          * Trim Acked data from output queue.
 425          */
 426         while ((m = so->so_snd.ssb_mb) != NULL) {
 427                 if (SSEQ_LT((mtod(m, struct spidp *))->si_seq, si->si_ack))
 428                         sbdroprecord(&so->so_snd.sb);
 429                 else
 430                         break;
 431         }
 432         sowwakeup(so);
 433         cb->s_rack = si->si_ack;
 434 update_window:
 435         if (SSEQ_LT(cb->s_snxt, cb->s_rack))
 436                 cb->s_snxt = cb->s_rack;
 437         if (SSEQ_LT(cb->s_swl1, si->si_seq) || (cb->s_swl1 == si->si_seq &&
 438             (SSEQ_LT(cb->s_swl2, si->si_ack) ||
 439                 (cb->s_swl2 == si->si_ack && SSEQ_LT(cb->s_ralo, si->si_alo))))) {
 440                 /* keep track of pure window updates */
 441                 if ((si->si_cc & SP_SP) && cb->s_swl2 == si->si_ack
 442                     && SSEQ_LT(cb->s_ralo, si->si_alo)) {
 443                         sppstat.spps_rcvwinupd++;
 444                         sppstat.spps_rcvdupack--;
 445                 }
 446                 cb->s_ralo = si->si_alo;
 447                 cb->s_swl1 = si->si_seq;
 448                 cb->s_swl2 = si->si_ack;
 449                 cb->s_swnd = (1 + si->si_alo - si->si_ack);
 450                 if (cb->s_swnd > cb->s_smxw)
 451                         cb->s_smxw = cb->s_swnd;
 452                 cb->s_flags |= SF_WIN;
 453         }
 454         /*
 455          * If this packet number is higher than that which
 456          * we have allocated refuse it, unless urgent
 457          */
 458         if (SSEQ_GT(si->si_seq, cb->s_alo)) {
 459                 if (si->si_cc & SP_SP) {
 460                         sppstat.spps_rcvwinprobe++;
 461                         return (1);
 462                 } else
 463                         sppstat.spps_rcvpackafterwin++;
 464                 if (si->si_cc & SP_OB) {
 465                         if (SSEQ_GT(si->si_seq, cb->s_alo + 60)) {
 466                                 ns_error(si_m, NS_ERR_FULLUP, 0);
 467                                 return (0);
 468                         } /* else queue this packet; */
 469                 } else {
 470                         /*register struct socket *so = cb->s_nspcb->nsp_socket;
 471                         if (so->so_state && SS_NOFDREF) {
 472                                 ns_error(si_m, NS_ERR_NOSOCK, 0);
 473                                 spp_close(cb);
 474                         } else
 475                                        would crash system*/
 476                         spp_istat.notyet++;
 477                         ns_error(si_m, NS_ERR_FULLUP, 0);
 478                         return (0);
 479                 }
 480         }
 481         /*
 482          * If this is a system packet, we don't need to
 483          * queue it up, and won't update acknowledge #
 484          */
 485         if (si->si_cc & SP_SP) {
 486                 return (1);
 487         }
 488         /*
 489          * We have already seen this packet, so drop.
 490          */
 491         if (SSEQ_LT(si->si_seq, cb->s_ack)) {
 492                 spp_istat.bdreas++;
 493                 sppstat.spps_rcvduppack++;
 494                 if (si->si_seq == cb->s_ack - 1)
 495                         spp_istat.lstdup++;
 496                 return (1);
 497         }
 498         /*
 499          * Loop through all packets queued up to insert in
 500          * appropriate sequence.
 501          */
 502         for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
 503                 if (si->si_seq == SI(q)->si_seq) {
 504                         sppstat.spps_rcvduppack++;
 505                         return (1);
 506                 }
 507                 if (SSEQ_LT(si->si_seq, SI(q)->si_seq)) {
 508                         sppstat.spps_rcvoopack++;
 509                         break;
 510                 }
 511         }
 512         nq = kmalloc(sizeof(struct spidp_q), M_SPIDP_Q, M_INTNOWAIT);
 513         if (nq == NULL) {
 514                 m_freem(si_m);
 515                 return(0);
 516         }
 517         insque(nq, q->si_prev);
 518         nq->si_mbuf = si_m;
 519         /*
 520          * If this packet is urgent, inform process
 521          */
 522         if (si->si_cc & SP_OB) {
 523                 cb->s_iobc = ((char *)si)[1 + sizeof(*si)];
 524                 sohasoutofband(so);
 525                 cb->s_oobflags |= SF_IOOB;
 526         }
 527 present:
 528 #define SPINC sizeof(struct sphdr)
 529         /*
 530          * Loop through all packets queued up to update acknowledge
 531          * number, and present all acknowledged data to user;
 532          * If in packet interface mode, show packet headers.
 533          */
 534         for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
 535                   if (SI(q)->si_seq == cb->s_ack) {
 536                         cb->s_ack++;
 537                         m = q->si_mbuf;
 538                         if (SI(q)->si_cc & SP_OB) {
 539                                 cb->s_oobflags &= ~SF_IOOB;
 540                                 if (so->so_rcv.ssb_cc)
 541                                         so->so_oobmark = so->so_rcv.ssb_cc;
 542                                 else
 543                                         so->so_state |= SS_RCVATMARK;
 544                         }
 545                         nq = q;
 546                         q = q->si_prev;
 547                         remque(nq);
 548                         kfree(nq, M_SPIDP_Q);
 549                         wakeup = 1;
 550                         sppstat.spps_rcvpack++;
 551 #ifdef SF_NEWCALL
 552                         if (cb->s_flags2 & SF_NEWCALL) {
 553                                 struct sphdr *sp = mtod(m, struct sphdr *);
 554                                 u_char dt = sp->sp_dt;
 555                                 spp_newchecks[4]++;
 556                                 if (dt != cb->s_rhdr.sp_dt) {
 557                                         struct mbuf *mm =
 558                                            m_getclr(MB_DONTWAIT, MT_CONTROL);
 559                                         spp_newchecks[0]++;
 560                                         if (mm != NULL) {
 561                                                 u_short *s =
 562                                                         mtod(mm, u_short *);
 563                                                 cb->s_rhdr.sp_dt = dt;
 564                                                 mm->m_len = 5; /*XXX*/
 565                                                 s[0] = 5;
 566                                                 s[1] = 1;
 567                                                 *(u_char *)(&s[2]) = dt;
 568                                                 sbappend(&so->so_rcv.sb, mm);
 569                                         }
 570                                 }
 571                                 if (sp->sp_cc & SP_OB) {
 572                                         m_chtype(m, MT_OOBDATA);
 573                                         spp_newchecks[1]++;
 574                                         so->so_oobmark = 0;
 575                                         so->so_state &= ~SS_RCVATMARK;
 576                                 }
 577                                 if (packetp == 0) {
 578                                         m->m_data += SPINC;
 579                                         m->m_len -= SPINC;
 580                                         m->m_pkthdr.len -= SPINC;
 581                                 }
 582                                 if ((sp->sp_cc & SP_EM) || packetp) {
 583                                         sbappendrecord(&so->so_rcv.sb, m);
 584                                         spp_newchecks[9]++;
 585                                 } else
 586                                         sbappend(&so->so_rcv.sb, m);
 587                         } else
 588 #endif
 589                         if (packetp) {
 590                                 sbappendrecord(&so->so_rcv.sb, m);
 591                         } else {
 592                                 cb->s_rhdr = *mtod(m, struct sphdr *);
 593                                 m->m_data += SPINC;
 594                                 m->m_len -= SPINC;
 595                                 m->m_pkthdr.len -= SPINC;
 596                                 sbappend(&so->so_rcv.sb, m);
 597                         }
 598                   } else
 599                         break;
 600         }
 601         if (wakeup) sorwakeup(so);
 602         return (0);
 603 }
 604
 605 void
 606 spp_ctlinput(int cmd, caddr_t arg)
 607 {
 608         struct ns_addr *na;
 609         struct ns_errp *errp = 0;
 610         struct nspcb *nsp;
 611         struct sockaddr_ns *sns;
 612         int type;
 613
 614         if (cmd < 0 || cmd > PRC_NCMDS)
 615                 return;
 616         type = NS_ERR_UNREACH_HOST;
 617
 618         switch (cmd) {
 619
 620         case PRC_ROUTEDEAD:
 621                 return;
 622
 623         case PRC_IFDOWN:
 624         case PRC_HOSTDEAD:
 625         case PRC_HOSTUNREACH:
 626                 sns = (struct sockaddr_ns *)arg;
 627                 if (sns->sns_family != AF_NS)
 628                         return;
 629                 na = &sns->sns_addr;
 630                 break;
 631
 632         default:
 633                 errp = (struct ns_errp *)arg;
 634                 na = &errp->ns_err_idp.idp_dna;
 635                 type = errp->ns_err_num;
 636                 type = ntohs((u_short)type);
 637         }
 638         switch (type) {
 639
 640         case NS_ERR_UNREACH_HOST:
 641                 ns_pcbnotify(na, (int)nsctlerrmap[cmd], spp_abort, (long) 0);
 642                 break;
 643
 644         case NS_ERR_TOO_BIG:
 645         case NS_ERR_NOSOCK:
 646                 nsp = ns_pcblookup(na, errp->ns_err_idp.idp_sna.x_port,
 647                         NS_WILDCARD);
 648                 if (nsp) {
 649                         if(nsp->nsp_pcb)
 650                                 spp_drop((struct sppcb *)nsp->nsp_pcb,
 651                                          (int)nsctlerrmap[cmd]);
 652                         else
 653                                 idp_drop(nsp, (int)nsctlerrmap[cmd]);
 654                 }
 655                 break;
 656
 657         case NS_ERR_FULLUP:
 658                 ns_pcbnotify(na, 0, spp_quench, (long) 0);
 659         }
 660 }
 661 /*
 662  * When a source quench is received, close congestion window
 663  * to one packet.  We will gradually open it again as we proceed.
 664  */
 665 void
 666 spp_quench(struct nspcb *nsp)
 667 {
 668         struct sppcb *cb = nstosppcb(nsp);
 669
 670         if (cb)
 671                 cb->s_cwnd = CUNIT;
 672 }
 673
 674 #ifdef notdef
 675 int
 676 spp_fixmtu(struct nspcb *nsp)
 677 {
 678         struct sppcb *cb = (struct sppcb *)(nsp->nsp_pcb);
 679         struct mbuf *m;
 680         struct spidp *si;
 681         struct ns_errp *ep;
 682         struct signalsockbuf *ssb;
 683         int badseq, len;
 684         struct mbuf *firstbad, *m0;
 685
 686         if (cb) {
 687                 /*
 688                  * The notification that we have sent
 689                  * too much is bad news -- we will
 690                  * have to go through queued up so far
 691                  * splitting ones which are too big and
 692                  * reassigning sequence numbers and checksums.
 693                  * we should then retransmit all packets from
 694                  * one above the offending packet to the last one
 695                  * we had sent (or our allocation)
 696                  * then the offending one so that the any queued
 697                  * data at our destination will be discarded.
 698                  */
 699                  ep = (struct ns_errp *)nsp->nsp_notify_param;
 700                  ssb = &nsp->nsp_socket->so_snd;
 701                  cb->s_mtu = ep->ns_err_param;
 702                  badseq = ep->ns_err_idp.si_seq;
 703                  for (m = ssb->ssb_mb; m; m = m->m_nextpkt) {
 704                         si = mtod(m, struct spidp *);
 705                         if (si->si_seq == badseq)
 706                                 break;
 707                  }
 708                  if (m == 0) return;
 709                  firstbad = m;
 710                  /*for (;;) {*/
 711                         /* calculate length */
 712                         for (m0 = m, len = 0; m ; m = m->m_next)
 713                                 len += m->m_len;
 714                         if (len > cb->s_mtu) {
 715                         }
 716                 /* FINISH THIS
 717                 } */
 718         }
 719 }
 720 #endif
 721
 722 int
 723 spp_output(struct sppcb *cb, struct mbuf *m0)
 724 {
 725         struct socket *so = cb->s_nspcb->nsp_socket;
 726         struct mbuf *m = NULL;
 727         struct spidp *si = NULL;
 728         struct signalsockbuf *ssb = &so->so_snd;
 729         int len = 0, win, rcv_win;
 730         short span, off, recordp = 0;
 731         u_short alo;
 732         int error = 0, sendalot;
 733 #ifdef notdef
 734         int idle;
 735 #endif
 736         struct mbuf *mprev;
 737
 738         if (m0) {
 739                 int mtu = cb->s_mtu;
 740                 int datalen;
 741                 /*
 742                  * Make sure that packet isn't too big.
 743                  */
 744                 for (m = m0; m ; m = m->m_next) {
 745                         mprev = m;
 746                         len += m->m_len;
 747                         if (m->m_flags & M_EOR)
 748                                 recordp = 1;
 749                 }
 750                 datalen = (cb->s_flags & SF_HO) ?
 751                                 len - sizeof (struct sphdr) : len;
 752                 if (datalen > mtu) {
 753                         if (cb->s_flags & SF_PI) {
 754                                 m_freem(m0);
 755                                 return (EMSGSIZE);
 756                         } else {
 757                                 int oldEM = cb->s_cc & SP_EM;
 758
 759                                 cb->s_cc &= ~SP_EM;
 760                                 while (len > mtu) {
 761                                         /*
 762                                          * Here we are only being called
 763                                          * from usrreq(), so it is OK to
 764                                          * block.
 765                                          */
 766                                         m = m_copym(m0, 0, mtu, MB_WAIT);
 767                                         if (cb->s_flags & SF_NEWCALL) {
 768                                             struct mbuf *mm = m;
 769                                             spp_newchecks[7]++;
 770                                             while (mm) {
 771                                                 mm->m_flags &= ~M_EOR;
 772                                                 mm = mm->m_next;
 773                                             }
 774                                         }
 775                                         error = spp_output(cb, m);
 776                                         if (error) {
 777                                                 cb->s_cc |= oldEM;
 778                                                 m_freem(m0);
 779                                                 return(error);
 780                                         }
 781                                         m_adj(m0, mtu);
 782                                         len -= mtu;
 783                                 }
 784                                 cb->s_cc |= oldEM;
 785                         }
 786                 }
 787                 /*
 788                  * Force length even, by adding a "garbage byte" if
 789                  * necessary.
 790                  */
 791                 if (len & 1) {
 792                         m = mprev;
 793                         if (M_TRAILINGSPACE(m) >= 1)
 794                                 m->m_len++;
 795                         else {
 796                                 struct mbuf *m1 = m_get(MB_DONTWAIT, MT_DATA);
 797
 798                                 if (m1 == 0) {
 799                                         m_freem(m0);
 800                                         return (ENOBUFS);
 801                                 }
 802                                 m1->m_len = 1;
 803                                 *(mtod(m1, u_char *)) = 0;
 804                                 m->m_next = m1;
 805                         }
 806                 }
 807                 m = m_gethdr(MB_DONTWAIT, MT_HEADER);
 808                 if (m == 0) {
 809                         m_freem(m0);
 810                         return (ENOBUFS);
 811                 }
 812                 /*
 813                  * Fill in mbuf with extended SP header
 814                  * and addresses and length put into network format.
 815                  */
 816                 MH_ALIGN(m, sizeof (struct spidp));
 817                 m->m_len = sizeof (struct spidp);
 818                 m->m_next = m0;
 819                 si = mtod(m, struct spidp *);
 820                 si->si_i = *cb->s_idp;
 821                 si->si_s = cb->s_shdr;
 822                 if ((cb->s_flags & SF_PI) && (cb->s_flags & SF_HO)) {
 823                         struct sphdr *sh;
 824                         if (m0->m_len < sizeof (*sh)) {
 825                                 if((m0 = m_pullup(m0, sizeof(*sh))) == NULL) {
 826                                         m_free(m);
 827                                         m_freem(m0);
 828                                         return (EINVAL);
 829                                 }
 830                                 m->m_next = m0;
 831                         }
 832                         sh = mtod(m0, struct sphdr *);
 833                         si->si_dt = sh->sp_dt;
 834                         si->si_cc |= sh->sp_cc & SP_EM;
 835                         m0->m_len -= sizeof (*sh);
 836                         m0->m_data += sizeof (*sh);
 837                         len -= sizeof (*sh);
 838                 }
 839                 len += sizeof(*si);
 840                 if ((cb->s_flags2 & SF_NEWCALL) && recordp) {
 841                         si->si_cc  |= SP_EM;
 842                         spp_newchecks[8]++;
 843                 }
 844                 if (cb->s_oobflags & SF_SOOB) {
 845                         /*
 846                          * Per jqj@cornell:
 847                          * make sure OB packets convey exactly 1 byte.
 848                          * If the packet is 1 byte or larger, we
 849                          * have already guaranted there to be at least
 850                          * one garbage byte for the checksum, and
 851                          * extra bytes shouldn't hurt!
 852                          */
 853                         if (len > sizeof(*si)) {
 854                                 si->si_cc |= SP_OB;
 855                                 len = (1 + sizeof(*si));
 856                         }
 857                 }
 858                 si->si_len = htons((u_short)len);
 859                 m->m_pkthdr.len = ((len - 1) | 1) + 1;
 860                 /*
 861                  * queue stuff up for output
 862                  */
 863                 sbappendrecord(&ssb->sb, m);
 864                 cb->s_seq++;
 865         }
 866 #ifdef notdef
 867         idle = (cb->s_smax == (cb->s_rack - 1));
 868 #endif
 869 again:
 870         sendalot = 0;
 871         off = cb->s_snxt - cb->s_rack;
 872         win = min(cb->s_swnd, (cb->s_cwnd/CUNIT));
 873
 874         /*
 875          * If in persist timeout with window of 0, send a probe.
 876          * Otherwise, if window is small but nonzero
 877          * and timer expired, send what we can and go into
 878          * transmit state.
 879          */
 880         if (cb->s_force == 1 + SPPT_PERSIST) {
 881                 if (win != 0) {
 882                         cb->s_timer[SPPT_PERSIST] = 0;
 883                         cb->s_rxtshift = 0;
 884                 }
 885         }
 886         span = cb->s_seq - cb->s_rack;
 887         len = min(span, win) - off;
 888
 889         if (len < 0) {
 890                 /*
 891                  * Window shrank after we went into it.
 892                  * If window shrank to 0, cancel pending
 893                  * restransmission and pull s_snxt back
 894                  * to (closed) window.  We will enter persist
 895                  * state below.  If the widndow didn't close completely,
 896                  * just wait for an ACK.
 897                  */
 898                 len = 0;
 899                 if (win == 0) {
 900                         cb->s_timer[SPPT_REXMT] = 0;
 901                         cb->s_snxt = cb->s_rack;
 902                 }
 903         }
 904         if (len > 1)
 905                 sendalot = 1;
 906         rcv_win = ssb_space(&so->so_rcv);
 907
 908         /*
 909          * Send if we owe peer an ACK.
 910          */
 911         if (cb->s_oobflags & SF_SOOB) {
 912                 /*
 913                  * must transmit this out of band packet
 914                  */
 915                 cb->s_oobflags &= ~ SF_SOOB;
 916                 sendalot = 1;
 917                 sppstat.spps_sndurg++;
 918                 goto found;
 919         }
 920         if (cb->s_flags & SF_ACKNOW)
 921                 goto send;
 922         if (cb->s_state < TCPS_ESTABLISHED)
 923                 goto send;
 924         /*
 925          * Silly window can't happen in spp.
 926          * Code from tcp deleted.
 927          */
 928         if (len)
 929                 goto send;
 930         /*
 931          * Compare available window to amount of window
 932          * known to peer (as advertised window less
 933          * next expected input.)  If the difference is at least two
 934          * packets or at least 35% of the mximum possible window,
 935          * then want to send a window update to peer.
 936          */
 937         if (rcv_win > 0) {
 938                 u_short delta =  1 + cb->s_alo - cb->s_ack;
 939                 int adv = rcv_win - (delta * cb->s_mtu);
 940
 941                 if ((so->so_rcv.ssb_cc == 0 && adv >= (2 * cb->s_mtu)) ||
 942                     (100 * adv / so->so_rcv.ssb_hiwat >= 35)) {
 943                         sppstat.spps_sndwinup++;
 944                         cb->s_flags |= SF_ACKNOW;
 945                         goto send;
 946                 }
 947
 948         }
 949         /*
 950          * Many comments from tcp_output.c are appropriate here
 951          * including . . .
 952          * If send window is too small, there is data to transmit, and no
 953          * retransmit or persist is pending, then go to persist state.
 954          * If nothing happens soon, send when timer expires:
 955          * if window is nonzero, transmit what we can,
 956          * otherwise send a probe.
 957          */
 958         if (so->so_snd.ssb_cc && cb->s_timer[SPPT_REXMT] == 0 &&
 959                 cb->s_timer[SPPT_PERSIST] == 0) {
 960                         cb->s_rxtshift = 0;
 961                         spp_setpersist(cb);
 962         }
 963         /*
 964          * No reason to send a packet, just return.
 965          */
 966         cb->s_outx = 1;
 967         return (0);
 968
 969 send:
 970         /*
 971          * Find requested packet.
 972          */
 973         si = NULL;
 974         if (len > 0) {
 975                 cb->s_want = cb->s_snxt;
 976                 for (m = ssb->ssb_mb; m; m = m->m_nextpkt) {
 977                         si = mtod(m, struct spidp *);
 978                         if (SSEQ_LEQ(cb->s_snxt, si->si_seq))
 979                                 break;
 980                 }
 981         found:
 982                 if (si) {
 983                         if (si->si_seq == cb->s_snxt)
 984                                         cb->s_snxt++;
 985                                 else
 986                                         sppstat.spps_sndvoid++, si = 0;
 987                 }
 988         }
 989         /*
 990          * update window
 991          */
 992         if (rcv_win < 0)
 993                 rcv_win = 0;
 994         alo = cb->s_ack - 1 + (rcv_win / ((short)cb->s_mtu));
 995         if (SSEQ_LT(alo, cb->s_alo))
 996                 alo = cb->s_alo;
 997
 998         if (si) {
 999                 /*
1000                  * must make a copy of this packet for
1001                  * idp_output to monkey with
1002                  */
1003                 m = m_copy(m, 0, (int)M_COPYALL);
1004                 if (m == NULL) {
1005                         return (ENOBUFS);
1006                 }
1007                 si = mtod(m, struct spidp *);
1008                 if (SSEQ_LT(si->si_seq, cb->s_smax))
1009                         sppstat.spps_sndrexmitpack++;
1010                 else
1011                         sppstat.spps_sndpack++;
1012         } else if (cb->s_force || cb->s_flags & SF_ACKNOW) {
1013                 /*
1014                  * Must send an acknowledgement or a probe
1015                  */
1016                 if (cb->s_force)
1017                         sppstat.spps_sndprobe++;
1018                 if (cb->s_flags & SF_ACKNOW)
1019                         sppstat.spps_sndacks++;
1020                 m = m_gethdr(MB_DONTWAIT, MT_HEADER);
1021                 if (m == 0)
1022                         return (ENOBUFS);
1023                 /*
1024                  * Fill in mbuf with extended SP header
1025                  * and addresses and length put into network format.
1026                  */
1027                 MH_ALIGN(m, sizeof (struct spidp));
1028                 m->m_len = sizeof (*si);
1029                 m->m_pkthdr.len = sizeof (*si);
1030                 si = mtod(m, struct spidp *);
1031                 si->si_i = *cb->s_idp;
1032                 si->si_s = cb->s_shdr;
1033                 si->si_seq = cb->s_smax + 1;
1034                 si->si_len = htons(sizeof (*si));
1035                 si->si_cc |= SP_SP;
1036         } else {
1037                 cb->s_outx = 3;
1038                 if (so->so_options & SO_DEBUG || traceallspps)
1039                         spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
1040                 return (0);
1041         }
1042         /*
1043          * Stuff checksum and output datagram.
1044          */
1045         if ((si->si_cc & SP_SP) == 0) {
1046                 if (cb->s_force != (1 + SPPT_PERSIST) ||
1047                     cb->s_timer[SPPT_PERSIST] == 0) {
1048                         /*
1049                          * If this is a new packet and we are not currently
1050                          * timing anything, time this one.
1051                          */
1052                         if (SSEQ_LT(cb->s_smax, si->si_seq)) {
1053                                 cb->s_smax = si->si_seq;
1054                                 if (cb->s_rtt == 0) {
1055                                         sppstat.spps_segstimed++;
1056                                         cb->s_rtseq = si->si_seq;
1057                                         cb->s_rtt = 1;
1058                                 }
1059                         }
1060                         /*
1061                          * Set rexmt timer if not currently set,
1062                          * Initial value for retransmit timer is smoothed
1063                          * round-trip time + 2 * round-trip time variance.
1064                          * Initialize shift counter which is used for backoff
1065                          * of retransmit time.
1066                          */
1067                         if (cb->s_timer[SPPT_REXMT] == 0 &&
1068                             cb->s_snxt != cb->s_rack) {
1069                                 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1070                                 if (cb->s_timer[SPPT_PERSIST]) {
1071                                         cb->s_timer[SPPT_PERSIST] = 0;
1072                                         cb->s_rxtshift = 0;
1073                                 }
1074                         }
1075                 } else if (SSEQ_LT(cb->s_smax, si->si_seq)) {
1076                         cb->s_smax = si->si_seq;
1077                 }
1078         } else if (cb->s_state < TCPS_ESTABLISHED) {
1079                 if (cb->s_rtt == 0)
1080                         cb->s_rtt = 1; /* Time initial handshake */
1081                 if (cb->s_timer[SPPT_REXMT] == 0)
1082                         cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1083         }
1084         {
1085                 /*
1086                  * Do not request acks when we ack their data packets or
1087                  * when we do a gratuitous window update.
1088                  */
1089                 if (((si->si_cc & SP_SP) == 0) || cb->s_force)
1090                                 si->si_cc |= SP_SA;
1091                 si->si_seq = htons(si->si_seq);
1092                 si->si_alo = htons(alo);
1093                 si->si_ack = htons(cb->s_ack);
1094
1095                 if (idpcksum) {
1096                         si->si_sum = 0;
1097                         len = ntohs(si->si_len);
1098                         if (len & 1)
1099                                 len++;
1100                         si->si_sum = ns_cksum(m, len);
1101                 } else
1102                         si->si_sum = 0xffff;
1103
1104                 cb->s_outx = 4;
1105                 if (so->so_options & SO_DEBUG || traceallspps)
1106                         spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
1107
1108                 if (so->so_options & SO_DONTROUTE)
1109                         error = ns_output(m, (struct route *)0, NS_ROUTETOIF);
1110                 else
1111                         error = ns_output(m, &cb->s_nspcb->nsp_route, 0);
1112         }
1113         if (error) {
1114                 return (error);
1115         }
1116         sppstat.spps_sndtotal++;
1117         /*
1118          * Data sent (as far as we can tell).
1119          * If this advertises a larger window than any other segment,
1120          * then remember the size of the advertized window.
1121          * Any pending ACK has now been sent.
1122          */
1123         cb->s_force = 0;
1124         cb->s_flags &= ~(SF_ACKNOW|SF_DELACK);
1125         if (SSEQ_GT(alo, cb->s_alo))
1126                 cb->s_alo = alo;
1127         if (sendalot)
1128                 goto again;
1129         cb->s_outx = 5;
1130         return (0);
1131 }
1132
1133 int spp_do_persist_panics = 0;
1134
1135 void
1136 spp_setpersist(struct sppcb *cb)
1137 {
1138         int t = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
1139
1140         if (cb->s_timer[SPPT_REXMT] && spp_do_persist_panics)
1141                 panic("spp_output REXMT");
1142         /*
1143          * Start/restart persistance timer.
1144          */
1145         SPPT_RANGESET(cb->s_timer[SPPT_PERSIST],
1146             t*spp_backoff[cb->s_rxtshift],
1147             SPPTV_PERSMIN, SPPTV_PERSMAX);
1148         if (cb->s_rxtshift < SPP_MAXRXTSHIFT)
1149                 cb->s_rxtshift++;
1150 }
1151 /*ARGSUSED*/
1152 int
1153 spp_ctloutput(int req, struct socket *so, int level,
1154                 int name, struct mbuf **value)
1155 {
1156         struct mbuf *m;
1157         struct nspcb *nsp = sotonspcb(so);
1158         struct sppcb *cb;
1159         int mask, error = 0;
1160
1161         if (level != NSPROTO_SPP) {
1162                 /* This will have to be changed when we do more general
1163                    stacking of protocols */
1164                 return (idp_ctloutput(req, so, level, name, value));
1165         }
1166         if (nsp == NULL) {
1167                 error = EINVAL;
1168                 goto release;
1169         } else
1170                 cb = nstosppcb(nsp);
1171
1172         switch (req) {
1173
1174         case PRCO_GETOPT:
1175                 if (value == NULL)
1176                         return (EINVAL);
1177                 m = m_get(MB_DONTWAIT, MT_DATA);
1178                 if (m == NULL)
1179                         return (ENOBUFS);
1180                 switch (name) {
1181
1182                 case SO_HEADERS_ON_INPUT:
1183                         mask = SF_HI;
1184                         goto get_flags;
1185
1186                 case SO_HEADERS_ON_OUTPUT:
1187                         mask = SF_HO;
1188                 get_flags:
1189                         m->m_len = sizeof(short);
1190                         *mtod(m, short *) = cb->s_flags & mask;
1191                         break;
1192
1193                 case SO_MTU:
1194                         m->m_len = sizeof(u_short);
1195                         *mtod(m, short *) = cb->s_mtu;
1196                         break;
1197
1198                 case SO_LAST_HEADER:
1199                         m->m_len = sizeof(struct sphdr);
1200                         *mtod(m, struct sphdr *) = cb->s_rhdr;
1201                         break;
1202
1203                 case SO_DEFAULT_HEADERS:
1204                         m->m_len = sizeof(struct spidp);
1205                         *mtod(m, struct sphdr *) = cb->s_shdr;
1206                         break;
1207
1208                 default:
1209                         error = EINVAL;
1210                 }
1211                 *value = m;
1212                 break;
1213
1214         case PRCO_SETOPT:
1215                 if (value == 0 || *value == 0) {
1216                         error = EINVAL;
1217                         break;
1218                 }
1219                 switch (name) {
1220                         int *ok;
1221
1222                 case SO_HEADERS_ON_INPUT:
1223                         mask = SF_HI;
1224                         goto set_head;
1225
1226                 case SO_HEADERS_ON_OUTPUT:
1227                         mask = SF_HO;
1228                 set_head:
1229                         if (cb->s_flags & SF_PI) {
1230                                 ok = mtod(*value, int *);
1231                                 if (*ok)
1232                                         cb->s_flags |= mask;
1233                                 else
1234                                         cb->s_flags &= ~mask;
1235                         } else error = EINVAL;
1236                         break;
1237
1238                 case SO_MTU:
1239                         cb->s_mtu = *(mtod(*value, u_short *));
1240                         break;
1241
1242 #ifdef SF_NEWCALL
1243                 case SO_NEWCALL:
1244                         ok = mtod(*value, int *);
1245                         if (*ok) {
1246                                 cb->s_flags2 |= SF_NEWCALL;
1247                                 spp_newchecks[5]++;
1248                         } else {
1249                                 cb->s_flags2 &= ~SF_NEWCALL;
1250                                 spp_newchecks[6]++;
1251                         }
1252                         break;
1253 #endif
1254
1255                 case SO_DEFAULT_HEADERS:
1256                         {
1257                                 struct sphdr *sp
1258                                                 = mtod(*value, struct sphdr *);
1259                                 cb->s_dt = sp->sp_dt;
1260                                 cb->s_cc = sp->sp_cc & SP_EM;
1261                         }
1262                         break;
1263
1264                 default:
1265                         error = EINVAL;
1266                 }
1267                 m_freem(*value);
1268                 break;
1269         }
1270         release:
1271                 return (error);
1272 }
1273
1274 /*
1275  *  SPP_USRREQ PROCEDURES
1276  */
1277
1278 static int
1279 spp_usr_abort(struct socket *so)
1280 {
1281         struct nspcb *nsp = sotonspcb(so);
1282         struct sppcb *cb;
1283         int error;
1284
1285         if (nsp) {
1286                 cb = nstosppcb(nsp);
1287                 spp_drop(cb, ECONNABORTED);
1288                 error = 0;
1289         } else {
1290                 error = EINVAL;
1291         }
1292         return(error);
1293 }
1294
1295 static int
1296 spp_accept(struct socket *so, struct sockaddr **nam)
1297 {
1298         struct nspcb *nsp = sotonspcb(so);
1299         struct sppcb *cb;
1300         struct sockaddr_ns sns;
1301         int error;
1302
1303         if (nsp) {
1304                 cb = nstosppcb(nsp);
1305                 bzero(&sns, sizeof(sns));
1306                 sns.sns_family = AF_NS;
1307                 sns.sns_addr = nsp->nsp_faddr;
1308                 *nam = dup_sockaddr((struct sockaddr *)&sns);
1309                 error = 0;
1310         } else {
1311                 error = EINVAL;
1312         }
1313         return(error);
1314 }
1315
1316 static int
1317 spp_attach(struct socket *so, int proto, struct pru_attach_info *ai)
1318 {
1319         struct nspcb *nsp = sotonspcb(so);
1320         struct sppcb *cb;
1321         struct signalsockbuf *ssb;
1322         int error;
1323
1324         if (nsp != NULL)
1325                 return(EISCONN);
1326         if ((error = ns_pcballoc(so, &nspcb)) != 0)
1327                 return(error);
1328         if (so->so_snd.ssb_hiwat == 0 || so->so_rcv.ssb_hiwat == 0) {
1329                 if ((error = soreserve(so, 3072, 3072, ai->sb_rlimit)) != 0)
1330                         return(error);
1331         }
1332         nsp = sotonspcb(so);
1333
1334         ssb = &so->so_snd;
1335         cb = kmalloc(sizeof(struct sppcb), M_SPPCB, M_WAITOK|M_ZERO);
1336         cb->s_idp = kmalloc(sizeof(struct idp), M_IDP, M_WAITOK|M_ZERO);
1337         cb->s_state = TCPS_LISTEN;
1338         cb->s_smax = -1;
1339         cb->s_swl1 = -1;
1340         cb->s_q.si_next = cb->s_q.si_prev = &cb->s_q;
1341         cb->s_nspcb = nsp;
1342         cb->s_mtu = 576 - sizeof (struct spidp);
1343         cb->s_cwnd = ssb_space(ssb) * CUNIT / cb->s_mtu;
1344         cb->s_ssthresh = cb->s_cwnd;
1345         cb->s_cwmx = ssb_space(ssb) * CUNIT / (2 * sizeof (struct spidp));
1346
1347         /*
1348          * Above is recomputed when connecting to account
1349          * for changed buffering or mtu's
1350          */
1351         cb->s_rtt = SPPTV_SRTTBASE;
1352         cb->s_rttvar = SPPTV_SRTTDFLT << 2;
1353         SPPT_RANGESET(cb->s_rxtcur,
1354                     ((SPPTV_SRTTBASE >> 2) + (SPPTV_SRTTDFLT << 2)) >> 1,
1355                     SPPTV_MIN, SPPTV_REXMTMAX);
1356         nsp->nsp_pcb = (caddr_t)cb;
1357         return(0);
1358 }
1359
1360 static int
1361 spp_attach_sp(struct socket *so, int proto, struct pru_attach_info *ai)
1362 {
1363         int error;
1364         struct nspcb *nsp;
1365
1366         if ((error = spp_attach(so, proto, ai)) == 0) {
1367                 nsp = sotonspcb(so);
1368                 ((struct sppcb *)nsp->nsp_pcb)->s_flags |=
1369                                         (SF_HI | SF_HO | SF_PI);
1370         }
1371         return (error);
1372 }
1373
1374 static int
1375 spp_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
1376 {
1377         struct nspcb *nsp = sotonspcb(so);
1378         int error;
1379
1380         if (nsp)
1381                 error = ns_pcbbind(nsp, nam);
1382         else
1383                 error = EINVAL;
1384         return(error);
1385 }
1386
1387 /*
1388  * Initiate connection to peer.
1389  * Enter SYN_SENT state, and mark socket as connecting.
1390  * Start keep-alive timer, setup prototype header,
1391  * Send initial system packet requesting connection.
1392  */
1393 static int
1394 spp_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
1395 {
1396         struct nspcb *nsp = sotonspcb(so);
1397         struct sppcb *cb;
1398         int error;
1399
1400         if (nsp) {
1401                 cb = nstosppcb(nsp);
1402                 if (nsp->nsp_lport == 0) {
1403                         if ((error = ns_pcbbind(nsp, NULL)) != 0)
1404                                 return(error);
1405                 }
1406                 if ((error = ns_pcbconnect(nsp, nam)) != 0)
1407                         return(error);
1408                 soisconnecting(so);
1409                 sppstat.spps_connattempt++;
1410                 cb->s_state = TCPS_SYN_SENT;
1411                 cb->s_did = 0;
1412                 spp_template(cb);
1413                 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
1414                 cb->s_force = 1 + SPPTV_KEEP;
1415                 /*
1416                  * Other party is required to respond to
1417                  * the port I send from, but he is not
1418                  * required to answer from where I am sending to,
1419                  * so allow wildcarding.
1420                  * original port I am sending to is still saved in
1421                  * cb->s_dport.
1422                  */
1423                 nsp->nsp_fport = 0;
1424                 error = spp_output(cb, NULL);
1425         } else {
1426                 error = EINVAL;
1427         }
1428         return(error);
1429 }
1430
1431 static int
1432 spp_detach(struct socket *so)
1433 {
1434         struct nspcb *nsp = sotonspcb(so);
1435         struct sppcb *cb;
1436
1437         if (nsp == NULL)
1438                 return(ENOTCONN);
1439         cb = nstosppcb(nsp);
1440         if (cb->s_state > TCPS_LISTEN)
1441                 spp_disconnect(cb);
1442         else
1443                 spp_close(cb);
1444         return(0);
1445 }
1446
1447 /*
1448  * We may decide later to implement connection closing
1449  * handshaking at the spp level optionally.
1450  * here is the hook to do it:
1451  */
1452 static int
1453 spp_usr_disconnect(struct socket *so)
1454 {
1455         struct nspcb *nsp = sotonspcb(so);
1456         struct sppcb *cb;
1457         int error;
1458
1459         if (nsp) {
1460                 cb = nstosppcb(nsp);
1461                 spp_disconnect(cb);
1462                 error = 0;
1463         } else {
1464                 error = EINVAL;
1465         }
1466         return(error);
1467 }
1468
1469 static int
1470 spp_listen(struct socket *so, struct thread *td)
1471 {
1472         struct nspcb *nsp = sotonspcb(so);
1473         struct sppcb *cb;
1474         int error;
1475
1476         if (nsp) {
1477                 cb = nstosppcb(nsp);
1478                 error = 0;
1479                 if (nsp->nsp_lport == 0)
1480                         error = ns_pcbbind(nsp, NULL);
1481                 if (error == 0)
1482                         cb->s_state = TCPS_LISTEN;
1483         } else {
1484                 error = EINVAL;
1485         }
1486         return(error);
1487 }
1488
1489 static int
1490 spp_peeraddr(struct socket *so, struct sockaddr **nam)
1491 {
1492         struct nspcb *nsp = sotonspcb(so);
1493         int error;
1494
1495         if (nsp) {
1496                 ns_setpeeraddr(nsp, nam);
1497                 error = 0;
1498         } else {
1499                 error = EINVAL;
1500         }
1501         return(error);
1502 }
1503
1504 static int
1505 spp_rcvd(struct socket *so, int flags)
1506 {
1507         struct nspcb *nsp = sotonspcb(so);
1508         struct sppcb *cb;
1509         int error;
1510
1511         if (nsp) {
1512                 cb = nstosppcb(nsp);
1513                 cb->s_flags |= SF_RVD;
1514                 spp_output(cb, (struct mbuf *) 0);
1515                 cb->s_flags &= ~SF_RVD;
1516                 error = 0;
1517         } else {
1518                 error = EINVAL;
1519         }
1520         return(error);
1521 }
1522
1523 static int
1524 spp_rcvoob(struct socket *so, struct mbuf *m, int flags)
1525 {
1526         struct nspcb *nsp = sotonspcb(so);
1527         struct sppcb *cb;
1528         int error;
1529
1530         if (nsp) {
1531                 cb = nstosppcb(nsp);
1532                 if ((cb->s_oobflags & SF_IOOB) || so->so_oobmark ||
1533                     (so->so_state & SS_RCVATMARK)) {
1534                         m->m_len = 1;
1535                         *mtod(m, caddr_t) = cb->s_iobc;
1536                         error = 0;
1537                 } else {
1538                         error = EINVAL;
1539                 }
1540         } else {
1541                 error = EINVAL;
1542         }
1543         return(error);
1544 }
1545
1546 static int
1547 spp_send(struct socket *so, int flags, struct mbuf *m,
1548         struct sockaddr *addr, struct mbuf *control,
1549         struct thread *td)
1550 {
1551         struct nspcb *nsp = sotonspcb(so);
1552         struct sppcb *cb;
1553         int error;
1554
1555         if (nsp) {
1556                 cb = nstosppcb(nsp);
1557                 error = 0;
1558                 if (flags & PRUS_OOB) {
1559                         if (ssb_space(&so->so_snd) < -512) {
1560                                 error = ENOBUFS;
1561                         } else {
1562                                 cb->s_oobflags |= SF_SOOB;
1563                         }
1564                 }
1565                 if (error == 0) {
1566                         if (control) {
1567                                 u_short *p = mtod(control, u_short *);
1568                                 spp_newchecks[2]++;
1569                                 /* XXXX, for testing */
1570                                 if ((p[0] == 5) && p[1] == 1) {
1571                                         cb->s_shdr.sp_dt = *(u_char *)(&p[2]);
1572                                         spp_newchecks[3]++;
1573                                 }
1574                                 m_freem(control);
1575                                 control = NULL;
1576                         }
1577                         error = spp_output(cb, m);
1578                         m = NULL;
1579                 }
1580         } else {
1581                 error = EINVAL;
1582         }
1583         if (m)
1584                 m_freem(m);
1585         if (control)
1586                 m_freem(control);
1587         return(error);
1588 }
1589
1590 static int
1591 spp_shutdown(struct socket *so)
1592 {
1593         struct nspcb *nsp = sotonspcb(so);
1594         struct sppcb *cb;
1595         int error;
1596
1597         if (nsp) {
1598                 cb = nstosppcb(nsp);
1599                 socantsendmore(so);
1600                 if ((cb = spp_usrclosed(cb)) != NULL)
1601                         error = spp_output(cb, NULL);
1602                 else
1603                         error = 0;
1604         } else {
1605                 error = EINVAL;
1606         }
1607         return(error);
1608 }
1609
1610 static int
1611 spp_sockaddr(struct socket *so, struct sockaddr **nam)
1612 {
1613         struct nspcb *nsp = sotonspcb(so);
1614         int error;
1615
1616         if (nsp) {
1617                 ns_setsockaddr(nsp, nam);
1618                 error = 0;
1619         } else {
1620                 error = EINVAL;
1621         }
1622         return(error);
1623 }
1624
1625 struct pr_usrreqs spp_usrreqs = {
1626         .pru_abort = spp_usr_abort,
1627         .pru_accept = spp_accept,
1628         .pru_attach = spp_attach,
1629         .pru_bind = spp_bind,
1630         .pru_connect = spp_connect,
1631         .pru_connect2 = pru_connect2_notsupp,
1632         .pru_control = ns_control,
1633         .pru_detach = spp_detach,
1634         .pru_disconnect = spp_usr_disconnect,
1635         .pru_listen = spp_listen,
1636         .pru_peeraddr = spp_peeraddr,
1637         .pru_rcvd = spp_rcvd,
1638         .pru_rcvoob = spp_rcvoob,
1639         .pru_send = spp_send,
1640         .pru_sense = pru_sense_null,
1641         .pru_shutdown = spp_shutdown,
1642         .pru_sockaddr = spp_sockaddr,
1643         .pru_sosend = sosend,
1644         .pru_soreceive = soreceive,
1645         .pru_sopoll = sopoll
1646 };
1647
1648 struct pr_usrreqs spp_usrreqs_sp = {
1649         .pru_abort = spp_usr_abort,
1650         .pru_accept = spp_accept,
1651         .pru_attach = spp_attach_sp,
1652         .pru_bind = spp_bind,
1653         .pru_connect = spp_connect,
1654         .pru_connect2 = pru_connect2_notsupp,
1655         .pru_control = ns_control,
1656         .pru_detach = spp_detach,
1657         .pru_disconnect = spp_usr_disconnect,
1658         .pru_listen = spp_listen,
1659         .pru_peeraddr = spp_peeraddr,
1660         .pru_rcvd = spp_rcvd,
1661         .pru_rcvoob = spp_rcvoob,
1662         .pru_send = spp_send,
1663         .pru_sense = pru_sense_null,
1664         .pru_shutdown = spp_shutdown,
1665         .pru_sockaddr = spp_sockaddr,
1666         .pru_sosend = sosend,
1667         .pru_soreceive = soreceive,
1668         .pru_sopoll = sopoll
1669 };
1670
1671 /*
1672  * Create template to be used to send spp packets on a connection.
1673  * Called after host entry created, fills
1674  * in a skeletal spp header (choosing connection id),
1675  * minimizing the amount of work necessary when the connection is used.
1676  */
1677 void
1678 spp_template(struct sppcb *cb)
1679 {
1680         struct nspcb *nsp = cb->s_nspcb;
1681         struct idp *idp = cb->s_idp;
1682         struct signalsockbuf *ssb = &(nsp->nsp_socket->so_snd);
1683
1684         idp->idp_pt = NSPROTO_SPP;
1685         idp->idp_sna = nsp->nsp_laddr;
1686         idp->idp_dna = nsp->nsp_faddr;
1687         cb->s_sid = htons(spp_iss);
1688         spp_iss += SPP_ISSINCR/2;
1689         cb->s_alo = 1;
1690         cb->s_cwnd = (ssb_space(ssb) * CUNIT) / cb->s_mtu;
1691         cb->s_ssthresh = cb->s_cwnd; /* Try to expand fast to full complement
1692                                         of large packets */
1693         cb->s_cwmx = (ssb_space(ssb) * CUNIT) / (2 * sizeof(struct spidp));
1694         cb->s_cwmx = max(cb->s_cwmx, cb->s_cwnd);
1695                 /* But allow for lots of little packets as well */
1696 }
1697
1698 /*
1699  * Close a SPIP control block:
1700  *      discard spp control block itself
1701  *      discard ns protocol control block
1702  *      wake up any sleepers
1703  */
1704 struct sppcb *
1705 spp_close(struct sppcb *cb)
1706 {
1707         struct spidp_q *q;
1708         struct spidp_q *oq;
1709         struct nspcb *nsp = cb->s_nspcb;
1710         struct socket *so = nsp->nsp_socket;
1711         struct mbuf *m;
1712
1713         q = cb->s_q.si_next;
1714         while (q != &(cb->s_q)) {
1715                 oq = q;
1716                 q = q->si_next;
1717                 m = oq->si_mbuf;
1718                 remque(oq);
1719                 m_freem(m);
1720                 kfree(oq, M_SPIDP_Q);
1721         }
1722         kfree(cb->s_idp, M_IDP);
1723         kfree(cb, M_SPPCB);
1724         nsp->nsp_pcb = 0;
1725         soisdisconnected(so);
1726         ns_pcbdetach(nsp);
1727         sppstat.spps_closed++;
1728         return ((struct sppcb *)0);
1729 }
1730 /*
1731  *      Someday we may do level 3 handshaking
1732  *      to close a connection or send a xerox style error.
1733  *      For now, just close.
1734  */
1735 struct sppcb *
1736 spp_usrclosed(struct sppcb *cb)
1737 {
1738         return (spp_close(cb));
1739 }
1740
1741 struct sppcb *
1742 spp_disconnect(struct sppcb *cb)
1743 {
1744         return (spp_close(cb));
1745 }
1746
1747 /*
1748  * Drop connection, reporting
1749  * the specified error.
1750  */
1751 struct sppcb *
1752 spp_drop(struct sppcb *cb, int error)
1753 {
1754         struct socket *so = cb->s_nspcb->nsp_socket;
1755
1756         /*
1757          * someday, in the xerox world
1758          * we will generate error protocol packets
1759          * announcing that the socket has gone away.
1760          */
1761         if (TCPS_HAVERCVDSYN(cb->s_state)) {
1762                 sppstat.spps_drops++;
1763                 cb->s_state = TCPS_CLOSED;
1764                 /*tcp_output(cb);*/
1765         } else
1766                 sppstat.spps_conndrops++;
1767         so->so_error = error;
1768         return (spp_close(cb));
1769 }
1770
1771 void
1772 spp_abort(struct nspcb *nsp)
1773 {
1774         spp_close((struct sppcb *)nsp->nsp_pcb);
1775 }
1776
1777 /*
1778  * Fast timeout routine for processing delayed acks
1779  */
1780 void
1781 spp_fasttimo(void)
1782 {
1783         struct nspcb *nsp;
1784         struct sppcb *cb;
1785
1786         crit_enter();
1787         nsp = nspcb.nsp_next;
1788         if (nsp) {
1789             for (; nsp != &nspcb; nsp = nsp->nsp_next) {
1790                 if ((cb = (struct sppcb *)nsp->nsp_pcb) &&
1791                     (cb->s_flags & SF_DELACK)) {
1792                         cb->s_flags &= ~SF_DELACK;
1793                         cb->s_flags |= SF_ACKNOW;
1794                         sppstat.spps_delack++;
1795                         spp_output(cb, (struct mbuf *) 0);
1796                 }
1797             }
1798         }
1799         crit_exit();
1800 }
1801
1802 /*
1803  * spp protocol timeout routine called every 500 ms.
1804  * Updates the timers in all active pcb's and
1805  * causes finite state machine actions if timers expire.
1806  */
1807 void
1808 spp_slowtimo(void)
1809 {
1810         struct nspcb *ip, *ipnxt;
1811         struct sppcb *cb;
1812         int i;
1813
1814         /*
1815          * Search through tcb's and update active timers.
1816          */
1817         crit_enter();
1818         ip = nspcb.nsp_next;
1819         if (ip == 0) {
1820                 crit_exit();
1821                 return;
1822         }
1823         while (ip != &nspcb) {
1824                 cb = nstosppcb(ip);
1825                 ipnxt = ip->nsp_next;
1826                 if (cb == 0)
1827                         goto tpgone;
1828                 for (i = 0; i < SPPT_NTIMERS; i++) {
1829                         if (cb->s_timer[i] && --cb->s_timer[i] == 0) {
1830                                 spp_timers(cb, i);
1831                                 if (ipnxt->nsp_prev != ip)
1832                                         goto tpgone;
1833                         }
1834                 }
1835                 cb->s_idle++;
1836                 if (cb->s_rtt)
1837                         cb->s_rtt++;
1838 tpgone:
1839                 ip = ipnxt;
1840         }
1841         spp_iss += SPP_ISSINCR/PR_SLOWHZ;               /* increment iss */
1842         crit_exit();
1843 }
1844 /*
1845  * SPP timer processing.
1846  */
1847 struct sppcb *
1848 spp_timers(struct sppcb *cb, int timer)
1849 {
1850         long rexmt;
1851         int win;
1852
1853         cb->s_force = 1 + timer;
1854         switch (timer) {
1855
1856         /*
1857          * 2 MSL timeout in shutdown went off.  TCP deletes connection
1858          * control block.
1859          */
1860         case SPPT_2MSL:
1861                 kprintf("spp: SPPT_2MSL went off for no reason\n");
1862                 cb->s_timer[timer] = 0;
1863                 break;
1864
1865         /*
1866          * Retransmission timer went off.  Message has not
1867          * been acked within retransmit interval.  Back off
1868          * to a longer retransmit interval and retransmit one packet.
1869          */
1870         case SPPT_REXMT:
1871                 if (++cb->s_rxtshift > SPP_MAXRXTSHIFT) {
1872                         cb->s_rxtshift = SPP_MAXRXTSHIFT;
1873                         sppstat.spps_timeoutdrop++;
1874                         cb = spp_drop(cb, ETIMEDOUT);
1875                         break;
1876                 }
1877                 sppstat.spps_rexmttimeo++;
1878                 rexmt = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
1879                 rexmt *= spp_backoff[cb->s_rxtshift];
1880                 SPPT_RANGESET(cb->s_rxtcur, rexmt, SPPTV_MIN, SPPTV_REXMTMAX);
1881                 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1882                 /*
1883                  * If we have backed off fairly far, our srtt
1884                  * estimate is probably bogus.  Clobber it
1885                  * so we'll take the next rtt measurement as our srtt;
1886                  * move the current srtt into rttvar to keep the current
1887                  * retransmit times until then.
1888                  */
1889                 if (cb->s_rxtshift > SPP_MAXRXTSHIFT / 4 ) {
1890                         cb->s_rttvar += (cb->s_srtt >> 2);
1891                         cb->s_srtt = 0;
1892                 }
1893                 cb->s_snxt = cb->s_rack;
1894                 /*
1895                  * If timing a packet, stop the timer.
1896                  */
1897                 cb->s_rtt = 0;
1898                 /*
1899                  * See very long discussion in tcp_timer.c about congestion
1900                  * window and sstrhesh
1901                  */
1902                 win = min(cb->s_swnd, (cb->s_cwnd/CUNIT)) / 2;
1903                 if (win < 2)
1904                         win = 2;
1905                 cb->s_cwnd = CUNIT;
1906                 cb->s_ssthresh = win * CUNIT;
1907                 spp_output(cb, (struct mbuf *) 0);
1908                 break;
1909
1910         /*
1911          * Persistance timer into zero window.
1912          * Force a probe to be sent.
1913          */
1914         case SPPT_PERSIST:
1915                 sppstat.spps_persisttimeo++;
1916                 spp_setpersist(cb);
1917                 spp_output(cb, (struct mbuf *) 0);
1918                 break;
1919
1920         /*
1921          * Keep-alive timer went off; send something
1922          * or drop connection if idle for too long.
1923          */
1924         case SPPT_KEEP:
1925                 sppstat.spps_keeptimeo++;
1926                 if (cb->s_state < TCPS_ESTABLISHED)
1927                         goto dropit;
1928                 if (cb->s_nspcb->nsp_socket->so_options & SO_KEEPALIVE) {
1929                         if (cb->s_idle >= SPPTV_MAXIDLE)
1930                                 goto dropit;
1931                         sppstat.spps_keepprobe++;
1932                         spp_output(cb, (struct mbuf *) 0);
1933                 } else
1934                         cb->s_idle = 0;
1935                 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
1936                 break;
1937         dropit:
1938                 sppstat.spps_keepdrops++;
1939                 cb = spp_drop(cb, ETIMEDOUT);
1940                 break;
1941         }
1942         return (cb);
1943 }
1944 #ifndef lint
1945 int SppcbSize = sizeof (struct sppcb);
1946 int NspcbSize = sizeof (struct nspcb);
1947 #endif /* lint */