2.11BSD#431 - /usr/src/sys/netns/spp_usrreq.c

   1: /*
   2:  * Copyright (c) 1984, 1985, 1986, 1987 Regents of the University of California.
   3:  * All rights reserved.
   4:  *
   5:  * Redistribution and use in source and binary forms are permitted
   6:  * provided that this notice is preserved and that due credit is given
   7:  * to the University of California at Berkeley. The name of the University
   8:  * may not be used to endorse or promote products derived from this
   9:  * software without specific prior written permission. This software
  10:  * is provided ``as is'' without express or implied warranty.
  11:  *
  12:  *      @(#)spp_usrreq.c	7.6 (Berkeley) 3/12/88
  13:  */
  14: 
  15: #include "param.h"
  16: #ifdef  NS
  17: #include "systm.h"
  18: #include "user.h"
  19: #include "mbuf.h"
  20: #include "protosw.h"
  21: #include "socket.h"
  22: #include "socketvar.h"
  23: #include "errno.h"
  24: 
  25: #include "../net/if.h"
  26: #include "../net/route.h"
  27: #include "../netinet/tcp_fsm.h"
  28: 
  29: #include "ns.h"
  30: #include "ns_pcb.h"
  31: #include "idp.h"
  32: #include "idp_var.h"
  33: #include "ns_error.h"
  34: #include "sp.h"
  35: #include "spidp.h"
  36: #include "spp_timer.h"
  37: #include "spp_var.h"
  38: #include "spp_debug.h"
  39: 
  40: /*
  41:  * SP protocol implementation.
  42:  */
  43: spp_init()
  44: {
  45: 
  46:     spp_iss = 1; /* WRONG !! should fish it out of TODR */
  47: }
  48: struct spidp spp_savesi;
  49: int traceallspps = 0;
  50: extern int sppconsdebug;
  51: int spp_hardnosed;
  52: int spp_use_delack = 0;
  53: 
  54: /*ARGSUSED*/
  55: spp_input(m, nsp, ifp)
  56:     register struct mbuf *m;
  57:     register struct nspcb *nsp;
  58:     struct ifnet *ifp;
  59: {
  60:     register struct sppcb *cb;
  61:     register struct spidp *si = mtod(m, struct spidp *);
  62:     register struct socket *so;
  63:     short ostate;
  64:     int dropsocket = 0;
  65: 
  66: 
  67:     sppstat.spps_rcvtotal++;
  68:     if (nsp == 0) {
  69:         panic("No nspcb in spp_input\n");
  70:         return;
  71:     }
  72: 
  73:     cb = nstosppcb(nsp);
  74:     if (cb == 0) goto bad;
  75: 
  76:     if (m->m_len < sizeof(*si)) {
  77:         if ((m = m_pullup(m, sizeof(*si))) == 0) {
  78:             sppstat.spps_rcvshort++;
  79:             return;
  80:         }
  81:         si = mtod(m, struct spidp *);
  82:     }
  83:     si->si_seq = ntohs(si->si_seq);
  84:     si->si_ack = ntohs(si->si_ack);
  85:     si->si_alo = ntohs(si->si_alo);
  86: 
  87:     so = nsp->nsp_socket;
  88:     if (so->so_options & SO_DEBUG || traceallspps) {
  89:         ostate = cb->s_state;
  90:         spp_savesi = *si;
  91:     }
  92:     if (so->so_options & SO_ACCEPTCONN) {
  93:         struct sppcb *ocb = cb;
  94:         struct socket *oso = so;
  95:         so = sonewconn(so);
  96:         if (so == 0) {
  97:             goto drop;
  98:         }
  99:         /*
 100: 		 * This is ugly, but ....
 101: 		 *
 102: 		 * Mark socket as temporary until we're
 103: 		 * committed to keeping it.  The code at
 104: 		 * ``drop'' and ``dropwithreset'' check the
 105: 		 * flag dropsocket to see if the temporary
 106: 		 * socket created here should be discarded.
 107: 		 * We mark the socket as discardable until
 108: 		 * we're committed to it below in TCPS_LISTEN.
 109: 		 */
 110:         dropsocket++;
 111:         nsp = (struct nspcb *)so->so_pcb;
 112:         nsp->nsp_laddr = si->si_dna;
 113:         cb = nstosppcb(nsp);
 114:         cb->s_mtu = ocb->s_mtu;     /* preserve sockopts */
 115:         cb->s_flags = ocb->s_flags; /* preserve sockopts */
 116:         if (so->so_snd.sb_hiwat != oso->so_snd.sb_hiwat) /*XXX*/
 117:             sbreserve(&so->so_snd, oso->so_snd.sb_hiwat);
 118:         if (so->so_rcv.sb_hiwat != oso->so_rcv.sb_hiwat) /*XXX*/
 119:             sbreserve(&so->so_rcv, oso->so_rcv.sb_hiwat);
 120:         cb->s_state = TCPS_LISTEN;
 121:     }
 122: 
 123:     /*
 124: 	 * Packet received on connection.
 125: 	 * reset idle time and keep-alive timer;
 126: 	 */
 127:     cb->s_idle = 0;
 128:     cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
 129: 
 130:     switch (cb->s_state) {
 131: 
 132:     case TCPS_LISTEN:{
 133:         struct mbuf *am;
 134:         register struct sockaddr_ns *sns;
 135:         struct ns_addr laddr;
 136: 
 137:         /*
 138: 		 * If somebody here was carying on a conversation
 139: 		 * and went away, and his pen pal thinks he can
 140: 		 * still talk, we get the misdirected packet.
 141: 		 */
 142:         if (spp_hardnosed && (si->si_did != 0 || si->si_seq != 0)) {
 143:             spp_istat.gonawy++;
 144:             goto dropwithreset;
 145:         }
 146:         am = m_get(M_DONTWAIT, MT_SONAME);
 147:         if (am == NULL)
 148:             goto drop;
 149:         am->m_len = sizeof (struct sockaddr_ns);
 150:         sns = mtod(am, struct sockaddr_ns *);
 151:         sns->sns_family = AF_NS;
 152:         sns->sns_addr = si->si_sna;
 153:         laddr = nsp->nsp_laddr;
 154:         if (ns_nullhost(laddr))
 155:             nsp->nsp_laddr = si->si_dna;
 156:         if (ns_pcbconnect(nsp, am)) {
 157:             nsp->nsp_laddr = laddr;
 158:             (void) m_free(am);
 159:             spp_istat.noconn++;
 160:             goto drop;
 161:         }
 162:         (void) m_free(am);
 163:         spp_template(cb);
 164:         dropsocket = 0;     /* committed to socket */
 165:         cb->s_did = si->si_sid;
 166:         cb->s_rack = si->si_ack;
 167:         cb->s_ralo = si->si_alo;
 168: #define THREEWAYSHAKE
 169: #ifdef THREEWAYSHAKE
 170:         cb->s_state = TCPS_SYN_RECEIVED;
 171:         cb->s_force = 1 + SPPT_KEEP;
 172:         sppstat.spps_accepts++;
 173:         cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
 174:         }
 175:         break;
 176:     /*
 177: 	 * This state means that we have heard a response
 178: 	 * to our acceptance of their connection
 179: 	 * It is probably logically unnecessary in this
 180: 	 * implementation.
 181: 	 */
 182:      case TCPS_SYN_RECEIVED: {
 183:         if (si->si_did!=cb->s_sid) {
 184:             spp_istat.wrncon++;
 185:             goto drop;
 186:         }
 187: #endif
 188:         nsp->nsp_fport =  si->si_sport;
 189:         cb->s_timer[SPPT_REXMT] = 0;
 190:         cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
 191:         soisconnected(so);
 192:         cb->s_state = TCPS_ESTABLISHED;
 193:         sppstat.spps_accepts++;
 194:         }
 195:         break;
 196: 
 197:     /*
 198: 	 * This state means that we have gotten a response
 199: 	 * to our attempt to establish a connection.
 200: 	 * We fill in the data from the other side,
 201: 	 * telling us which port to respond to, instead of the well-
 202: 	 * known one we might have sent to in the first place.
 203: 	 * We also require that this is a response to our
 204: 	 * connection id.
 205: 	 */
 206:     case TCPS_SYN_SENT:
 207:         if (si->si_did!=cb->s_sid) {
 208:             spp_istat.notme++;
 209:             goto drop;
 210:         }
 211:         sppstat.spps_connects++;
 212:         cb->s_did = si->si_sid;
 213:         cb->s_rack = si->si_ack;
 214:         cb->s_ralo = si->si_alo;
 215:         cb->s_dport = nsp->nsp_fport =  si->si_sport;
 216:         cb->s_timer[SPPT_REXMT] = 0;
 217:         cb->s_flags |= SF_ACKNOW;
 218:         soisconnected(so);
 219:         cb->s_state = TCPS_ESTABLISHED;
 220:         /* Use roundtrip time of connection request for initial rtt */
 221:         if (cb->s_rtt) {
 222:             cb->s_srtt = cb->s_rtt << 3;
 223:             cb->s_rttvar = cb->s_rtt << 1;
 224:             SPPT_RANGESET(cb->s_rxtcur,
 225:                 ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
 226:                 SPPTV_MIN, SPPTV_REXMTMAX);
 227:                 cb->s_rtt = 0;
 228:         }
 229:     }
 230:     if (so->so_options & SO_DEBUG || traceallspps)
 231:         spp_trace(SA_INPUT, (u_char)ostate, cb, &spp_savesi, 0);
 232: 
 233:     m->m_len -= sizeof (struct idp);
 234:     m->m_off += sizeof (struct idp);
 235: 
 236:     if (spp_reass(cb, si)) {
 237:         (void) m_freem(m);
 238:     }
 239:     if (cb->s_force || (cb->s_flags & (SF_ACKNOW|SF_WIN|SF_RXT)))
 240:         (void) spp_output(cb, (struct mbuf *)0);
 241:     cb->s_flags &= ~(SF_WIN|SF_RXT);
 242:     return;
 243: 
 244: dropwithreset:
 245:     if (dropsocket)
 246:         (void) soabort(so);
 247:     si->si_seq = ntohs(si->si_seq);
 248:     si->si_ack = ntohs(si->si_ack);
 249:     si->si_alo = ntohs(si->si_alo);
 250:     ns_error(dtom(si), NS_ERR_NOSOCK, 0);
 251:     if (cb->s_nspcb->nsp_socket->so_options & SO_DEBUG || traceallspps)
 252:         spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);
 253:     return;
 254: 
 255: drop:
 256: bad:
 257:     if (cb == 0 || cb->s_nspcb->nsp_socket->so_options & SO_DEBUG ||
 258:             traceallspps)
 259:         spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);
 260:     m_freem(m);
 261: }
 262: 
 263: int spprexmtthresh = 3;
 264: 
 265: /*
 266:  * This is structurally similar to the tcp reassembly routine
 267:  * but its function is somewhat different:  It merely queues
 268:  * packets up, and suppresses duplicates.
 269:  */
 270: spp_reass(cb, si)
 271: register struct sppcb *cb;
 272: register struct spidp *si;
 273: {
 274:     register struct spidp_q *q;
 275:     register struct mbuf *m;
 276:     register struct socket *so = cb->s_nspcb->nsp_socket;
 277:     char packetp = cb->s_flags & SF_HI;
 278:     int incr;
 279:     char wakeup = 0;
 280: 
 281:     if (si == SI(0))
 282:         goto present;
 283:     /*
 284: 	 * Update our news from them.
 285: 	 */
 286:     if (si->si_cc & SP_SA)
 287:         cb->s_flags |= (spp_use_delack ? SF_DELACK : SF_ACKNOW);
 288:     if (SSEQ_GT(si->si_alo, cb->s_ralo))
 289:         cb->s_flags |= SF_WIN;
 290:     if (SSEQ_LEQ(si->si_ack, cb->s_rack)) {
 291:         if ((si->si_cc & SP_SP) && cb->s_rack != (cb->s_smax + 1)) {
 292:             sppstat.spps_rcvdupack++;
 293:             /*
 294: 			 * If this is a completely duplicate ack
 295: 			 * and other conditions hold, we assume
 296: 			 * a packet has been dropped and retransmit
 297: 			 * it exactly as in tcp_input().
 298: 			 */
 299:             if (si->si_ack != cb->s_rack ||
 300:                 si->si_alo != cb->s_ralo)
 301:                 cb->s_dupacks = 0;
 302:             else if (++cb->s_dupacks == spprexmtthresh) {
 303:                 u_short onxt = cb->s_snxt;
 304:                 int cwnd = cb->s_cwnd;
 305: 
 306:                 cb->s_snxt = si->si_ack;
 307:                 cb->s_cwnd = CUNIT;
 308:                 cb->s_force = 1 + SPPT_REXMT;
 309:                 (void) spp_output(cb, (struct mbuf *)0);
 310:                 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
 311:                 cb->s_rtt = 0;
 312:                 if (cwnd >= 4 * CUNIT)
 313:                     cb->s_cwnd = cwnd / 2;
 314:                 if (SSEQ_GT(onxt, cb->s_snxt))
 315:                     cb->s_snxt = onxt;
 316:                 return (1);
 317:             }
 318:         } else
 319:             cb->s_dupacks = 0;
 320:         goto update_window;
 321:     }
 322:     cb->s_dupacks = 0;
 323:     /*
 324: 	 * If our correspondent acknowledges data we haven't sent
 325: 	 * TCP would drop the packet after acking.  We'll be a little
 326: 	 * more permissive
 327: 	 */
 328:     if (SSEQ_GT(si->si_ack, (cb->s_smax + 1))) {
 329:         sppstat.spps_rcvacktoomuch++;
 330:         si->si_ack = cb->s_smax + 1;
 331:     }
 332:     sppstat.spps_rcvackpack++;
 333:     /*
 334: 	 * If transmit timer is running and timed sequence
 335: 	 * number was acked, update smoothed round trip time.
 336: 	 * See discussion of algorithm in tcp_input.c
 337: 	 */
 338:     if (cb->s_rtt && SSEQ_GT(si->si_ack, cb->s_rtseq)) {
 339:         sppstat.spps_rttupdated++;
 340:         if (cb->s_srtt != 0) {
 341:             register short delta;
 342:             delta = cb->s_rtt - (cb->s_srtt >> 3);
 343:             if ((cb->s_srtt += delta) <= 0)
 344:                 cb->s_srtt = 1;
 345:             if (delta < 0)
 346:                 delta = -delta;
 347:             delta -= (cb->s_rttvar >> 2);
 348:             if ((cb->s_rttvar += delta) <= 0)
 349:                 cb->s_rttvar = 1;
 350:         } else {
 351:             /*
 352: 			 * No rtt measurement yet
 353: 			 */
 354:             cb->s_srtt = cb->s_rtt << 3;
 355:             cb->s_rttvar = cb->s_rtt << 1;
 356:         }
 357:         cb->s_rtt = 0;
 358:         cb->s_rxtshift = 0;
 359:         SPPT_RANGESET(cb->s_rxtcur,
 360:             ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
 361:             SPPTV_MIN, SPPTV_REXMTMAX);
 362:     }
 363:     /*
 364: 	 * If all outstanding data is acked, stop retransmit
 365: 	 * timer and remember to restart (more output or persist).
 366: 	 * If there is more data to be acked, restart retransmit
 367: 	 * timer, using current (possibly backed-off) value;
 368: 	 */
 369:     if (si->si_ack == cb->s_smax + 1) {
 370:         cb->s_timer[SPPT_REXMT] = 0;
 371:         cb->s_flags |= SF_RXT;
 372:     } else if (cb->s_timer[SPPT_PERSIST] == 0)
 373:         cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
 374:     /*
 375: 	 * When new data is acked, open the congestion window.
 376: 	 * If the window gives us less than ssthresh packets
 377: 	 * in flight, open exponentially (maxseg at a time).
 378: 	 * Otherwise open linearly (maxseg^2 / cwnd at a time).
 379: 	 */
 380:     incr = CUNIT;
 381:     if (cb->s_cwnd > cb->s_ssthresh)
 382:         incr = MAX(incr * incr / cb->s_cwnd, 1);
 383:     cb->s_cwnd = MIN(cb->s_cwnd + incr, cb->s_cwmx);
 384:     /*
 385: 	 * Trim Acked data from output queue.
 386: 	 */
 387:     while ((m = so->so_snd.sb_mb) != NULL) {
 388:         if (SSEQ_LT((mtod(m, struct spidp *))->si_seq, si->si_ack))
 389:             sbdroprecord(&so->so_snd);
 390:         else
 391:             break;
 392:     }
 393:     if ((so->so_snd.sb_flags & SB_WAIT) || so->so_snd.sb_sel)
 394:          sowwakeup(so);
 395:     cb->s_rack = si->si_ack;
 396: update_window:
 397:     if (SSEQ_LT(cb->s_snxt, cb->s_rack))
 398:         cb->s_snxt = cb->s_rack;
 399:     if (SSEQ_LT(cb->s_swl1, si->si_seq) || cb->s_swl1 == si->si_seq &&
 400:         (SSEQ_LT(cb->s_swl2, si->si_ack) ||
 401:          cb->s_swl2 == si->si_ack && SSEQ_LT(cb->s_ralo, si->si_alo))) {
 402:         /* keep track of pure window updates */
 403:         if ((si->si_cc & SP_SP) && cb->s_swl2 == si->si_ack
 404:             && SSEQ_LT(cb->s_ralo, si->si_alo)) {
 405:             sppstat.spps_rcvwinupd++;
 406:             sppstat.spps_rcvdupack--;
 407:         }
 408:         cb->s_ralo = si->si_alo;
 409:         cb->s_swl1 = si->si_seq;
 410:         cb->s_swl2 = si->si_ack;
 411:         cb->s_swnd = (1 + si->si_alo - si->si_ack);
 412:         if (cb->s_swnd > cb->s_smxw)
 413:             cb->s_smxw = cb->s_swnd;
 414:         cb->s_flags |= SF_WIN;
 415:     }
 416:     /*
 417: 	 * If this packet number is higher than that which
 418: 	 * we have allocated refuse it, unless urgent
 419: 	 */
 420:     if (SSEQ_GT(si->si_seq, cb->s_alo)) {
 421:         if (si->si_cc & SP_SP) {
 422:             sppstat.spps_rcvwinprobe++;
 423:             return (1);
 424:         } else
 425:             sppstat.spps_rcvpackafterwin++;
 426:         if (si->si_cc & SP_OB) {
 427:             if (SSEQ_GT(si->si_seq, cb->s_alo + 60)) {
 428:                 ns_error(dtom(si), NS_ERR_FULLUP, 0);
 429:                 return (0);
 430:             } /* else queue this packet; */
 431:         } else {
 432:             /*register struct socket *so = cb->s_nspcb->nsp_socket;
 433: 			if (so->so_state && SS_NOFDREF) {
 434: 				ns_error(dtom(si), NS_ERR_NOSOCK, 0);
 435: 				(void)spp_close(cb);
 436: 			} else
 437: 				       would crash system*/
 438:             spp_istat.notyet++;
 439:             ns_error(dtom(si), NS_ERR_FULLUP, 0);
 440:             return (0);
 441:         }
 442:     }
 443:     /*
 444: 	 * If this is a system packet, we don't need to
 445: 	 * queue it up, and won't update acknowledge #
 446: 	 */
 447:     if (si->si_cc & SP_SP) {
 448:         return (1);
 449:     }
 450:     /*
 451: 	 * We have already seen this packet, so drop.
 452: 	 */
 453:     if (SSEQ_LT(si->si_seq, cb->s_ack)) {
 454:         spp_istat.bdreas++;
 455:         sppstat.spps_rcvduppack++;
 456:         if (si->si_seq == cb->s_ack - 1)
 457:             spp_istat.lstdup++;
 458:         return (1);
 459:     }
 460:     /*
 461: 	 * Loop through all packets queued up to insert in
 462: 	 * appropriate sequence.
 463: 	 */
 464:     for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
 465:         if (si->si_seq == SI(q)->si_seq) {
 466:             sppstat.spps_rcvduppack++;
 467:             return (1);
 468:         }
 469:         if (SSEQ_LT(si->si_seq, SI(q)->si_seq)) {
 470:             sppstat.spps_rcvoopack++;
 471:             break;
 472:         }
 473:     }
 474:     insque(si, q->si_prev);
 475:     /*
 476: 	 * If this packet is urgent, inform process
 477: 	 */
 478:     if (si->si_cc & SP_OB) {
 479:         cb->s_iobc = ((char *)si)[1 + sizeof(*si)];
 480:         sohasoutofband(so);
 481:         cb->s_oobflags |= SF_IOOB;
 482:     }
 483: present:
 484: #define SPINC sizeof(struct sphdr)
 485:     /*
 486: 	 * Loop through all packets queued up to update acknowledge
 487: 	 * number, and present all acknowledged data to user;
 488: 	 * If in packet interface mode, show packet headers.
 489: 	 */
 490:     for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
 491:           if (SI(q)->si_seq == cb->s_ack) {
 492:             cb->s_ack++;
 493:             m = dtom(q);
 494:             if (SI(q)->si_cc & SP_OB) {
 495:                 cb->s_oobflags &= ~SF_IOOB;
 496:                 if (so->so_rcv.sb_cc)
 497:                     so->so_oobmark = so->so_rcv.sb_cc;
 498:                 else
 499:                     so->so_state |= SS_RCVATMARK;
 500:             }
 501:             q = q->si_prev;
 502:             remque(q->si_next);
 503:             wakeup = 1;
 504:             sppstat.spps_rcvpack++;
 505:             if (packetp) {
 506:                 sbappendrecord(&so->so_rcv, m);
 507:             } else {
 508:                 cb->s_rhdr = *mtod(m, struct sphdr *);
 509:                 m->m_off += SPINC;
 510:                 m->m_len -= SPINC;
 511:                 sbappend(&so->so_rcv, m);
 512:             }
 513:           } else
 514:             break;
 515:     }
 516:     if (wakeup) sorwakeup(so);
 517:     return (0);
 518: }
 519: 
 520: spp_ctlinput(cmd, arg)
 521:     int cmd;
 522:     caddr_t arg;
 523: {
 524:     struct ns_addr *na;
 525:     extern u_char nsctlerrmap[];
 526:     extern spp_abort(), spp_quench();
 527:     extern struct nspcb *idp_drop();
 528:     struct ns_errp *errp;
 529:     struct nspcb *nsp;
 530:     struct sockaddr_ns *sns;
 531:     int type;
 532: 
 533:     if (cmd < 0 || cmd > PRC_NCMDS)
 534:         return;
 535:     type = NS_ERR_UNREACH_HOST;
 536: 
 537:     switch (cmd) {
 538: 
 539:     case PRC_ROUTEDEAD:
 540:         return;
 541: 
 542:     case PRC_IFDOWN:
 543:     case PRC_HOSTDEAD:
 544:     case PRC_HOSTUNREACH:
 545:         sns = (struct sockaddr_ns *)arg;
 546:         if (sns->sns_family != AF_NS)
 547:             return;
 548:         na = &sns->sns_addr;
 549:         break;
 550: 
 551:     default:
 552:         errp = (struct ns_errp *)arg;
 553:         na = &errp->ns_err_idp.idp_dna;
 554:         type = errp->ns_err_num;
 555:         type = ntohs((u_short)type);
 556:     }
 557:     switch (type) {
 558: 
 559:     case NS_ERR_UNREACH_HOST:
 560:         ns_pcbnotify(na, (int)nsctlerrmap[cmd], spp_abort, (long) 0);
 561:         break;
 562: 
 563:     case NS_ERR_TOO_BIG:
 564:     case NS_ERR_NOSOCK:
 565:         nsp = ns_pcblookup(na, errp->ns_err_idp.idp_sna.x_port,
 566:             NS_WILDCARD);
 567:         if (nsp) {
 568:             if(nsp->nsp_pcb)
 569:                 (void) spp_drop((struct sppcb *)nsp->nsp_pcb,
 570:                         (int)nsctlerrmap[cmd]);
 571:             else
 572:                 (void) idp_drop(nsp, (int)nsctlerrmap[cmd]);
 573:         }
 574:         break;
 575: 
 576:     case NS_ERR_FULLUP:
 577:         ns_pcbnotify(na, 0, spp_quench, (long) 0);
 578:     }
 579: }
 580: /*
 581:  * When a source quench is received, close congestion window
 582:  * to one packet.  We will gradually open it again as we proceed.
 583:  */
 584: spp_quench(nsp)
 585:     struct nspcb *nsp;
 586: {
 587:     struct sppcb *cb = nstosppcb(nsp);
 588: 
 589:     if (cb)
 590:         cb->s_cwnd = CUNIT;
 591: }
 592: 
 593: #ifdef notdef
 594: int
 595: spp_fixmtu(nsp)
 596: register struct nspcb *nsp;
 597: {
 598:     register struct sppcb *cb = (struct sppcb *)(nsp->nsp_pcb);
 599:     register struct mbuf *m;
 600:     register struct spidp *si;
 601:     struct ns_errp *ep;
 602:     struct sockbuf *sb;
 603:     int badseq, len;
 604:     struct mbuf *firstbad, *m0;
 605: 
 606:     if (cb) {
 607:         /*
 608: 		 * The notification that we have sent
 609: 		 * too much is bad news -- we will
 610: 		 * have to go through queued up so far
 611: 		 * splitting ones which are too big and
 612: 		 * reassigning sequence numbers and checksums.
 613: 		 * we should then retransmit all packets from
 614: 		 * one above the offending packet to the last one
 615: 		 * we had sent (or our allocation)
 616: 		 * then the offending one so that the any queued
 617: 		 * data at our destination will be discarded.
 618: 		 */
 619:          ep = (struct ns_errp *)nsp->nsp_notify_param;
 620:          sb = &nsp->nsp_socket->so_snd;
 621:          cb->s_mtu = ep->ns_err_param;
 622:          badseq = SI(&ep->ns_err_idp)->si_seq;
 623:          for (m = sb->sb_mb; m; m = m->m_act) {
 624:             si = mtod(m, struct spidp *);
 625:             if (si->si_seq == badseq)
 626:                 break;
 627:          }
 628:          if (m == 0) return;
 629:          firstbad = m;
 630:          /*for (;;) {*/
 631:             /* calculate length */
 632:             for (m0 = m, len = 0; m ; m = m->m_next)
 633:                 len += m->m_len;
 634:             if (len > cb->s_mtu) {
 635:             }
 636:         /* FINISH THIS
 637: 		} */
 638:     }
 639: }
 640: #endif
 641: 
 642: spp_output(cb, m0)
 643:     register struct sppcb *cb;
 644:     struct mbuf *m0;
 645: {
 646:     struct socket *so = cb->s_nspcb->nsp_socket;
 647:     register struct mbuf *m;
 648:     register struct spidp *si = (struct spidp *) 0;
 649:     register struct sockbuf *sb = &so->so_snd;
 650:     int len = 0, win, rcv_win;
 651:     short span, off;
 652:     u_short alo;
 653:     int error = 0, idle, sendalot;
 654:     struct mbuf *mprev;
 655:     extern int idpcksum;
 656: 
 657:     if (m0) {
 658:         int mtu = cb->s_mtu;
 659:         int datalen;
 660:         /*
 661: 		 * Make sure that packet isn't too big.
 662: 		 */
 663:         for (m = m0; m ; m = m->m_next) {
 664:             mprev = m;
 665:             len += m->m_len;
 666:         }
 667:         datalen = (cb->s_flags & SF_HO) ?
 668:                 len - sizeof (struct sphdr) : len;
 669:         if (datalen > mtu) {
 670:             if (cb->s_flags & SF_PI) {
 671:                 m_freem(m0);
 672:                 return (EMSGSIZE);
 673:             } else {
 674:                 int oldEM = cb->s_cc & SP_EM;
 675: 
 676:                 cb->s_cc &= ~SP_EM;
 677:                 while (len > mtu) {
 678:                     m = m_copy(m0, 0, mtu);
 679:                     if (m == NULL) {
 680:                         error = ENOBUFS;
 681:                         goto bad_copy;
 682:                     }
 683:                     error = spp_output(cb, m);
 684:                     if (error) {
 685:                     bad_copy:
 686:                         cb->s_cc |= oldEM;
 687:                         m_freem(m0);
 688:                         return(error);
 689:                     }
 690:                     m_adj(m0, mtu);
 691:                     len -= mtu;
 692:                 }
 693:                 cb->s_cc |= oldEM;
 694:             }
 695:         }
 696:         /*
 697: 		 * Force length even, by adding a "garbage byte" if
 698: 		 * necessary.
 699: 		 */
 700:         if (len & 1) {
 701:             m = mprev;
 702:             if (m->m_len + m->m_off < MMAXOFF)
 703:                 m->m_len++;
 704:             else {
 705:                 struct mbuf *m1 = m_get(M_DONTWAIT, MT_DATA);
 706: 
 707:                 if (m1 == 0) {
 708:                     m_freem(m0);
 709:                     return (ENOBUFS);
 710:                 }
 711:                 m1->m_len = 1;
 712:                 m1->m_off = MMAXOFF - 1;
 713:                 m->m_next = m1;
 714:             }
 715:         }
 716:         m = m_get(M_DONTWAIT, MT_HEADER);
 717:         if (m == 0) {
 718:             m_freem(m0);
 719:             return (ENOBUFS);
 720:         }
 721:         /*
 722: 		 * Fill in mbuf with extended SP header
 723: 		 * and addresses and length put into network format.
 724: 		 * Long align so prepended ip headers will work on Gould.
 725: 		 */
 726:         m->m_off = MMAXOFF - sizeof (struct spidp) - 2;
 727:         m->m_len = sizeof (struct spidp);
 728:         m->m_next = m0;
 729:         si = mtod(m, struct spidp *);
 730:         si->si_i = *cb->s_idp;
 731:         si->si_s = cb->s_shdr;
 732:         if ((cb->s_flags & SF_PI) && (cb->s_flags & SF_HO)) {
 733:             register struct sphdr *sh;
 734:             if (m0->m_len < sizeof (*sh)) {
 735:                 if((m0 = m_pullup(m0, sizeof(*sh))) == NULL) {
 736:                     (void) m_free(m);
 737:                     m_freem(m0);
 738:                     return (EINVAL);
 739:                 }
 740:                 m->m_next = m0;
 741:             }
 742:             sh = mtod(m0, struct sphdr *);
 743:             si->si_dt = sh->sp_dt;
 744:             si->si_cc |= sh->sp_cc & SP_EM;
 745:             m0->m_len -= sizeof (*sh);
 746:             m0->m_off += sizeof (*sh);
 747:             len -= sizeof (*sh);
 748:         }
 749:         len += sizeof(*si);
 750:         if (cb->s_oobflags & SF_SOOB) {
 751:             /*
 752: 			 * Per jqj@cornell:
 753: 			 * make sure OB packets convey exactly 1 byte.
 754: 			 * If the packet is 1 byte or larger, we
 755: 			 * have already guaranted there to be at least
 756: 			 * one garbage byte for the checksum, and
 757: 			 * extra bytes shouldn't hurt!
 758: 			 */
 759:             if (len > sizeof(*si)) {
 760:                 si->si_cc |= SP_OB;
 761:                 len = (1 + sizeof(*si));
 762:             }
 763:         }
 764:         si->si_len = htons((u_short)len);
 765:         /*
 766: 		 * queue stuff up for output
 767: 		 */
 768:         sbappendrecord(sb, m);
 769:         cb->s_seq++;
 770:     }
 771:     idle = (cb->s_smax == (cb->s_rack - 1));
 772: again:
 773:     sendalot = 0;
 774:     off = cb->s_snxt - cb->s_rack;
 775:     win = MIN(cb->s_swnd, (cb->s_cwnd/CUNIT));
 776: 
 777:     /*
 778: 	 * If in persist timeout with window of 0, send a probe.
 779: 	 * Otherwise, if window is small but nonzero
 780: 	 * and timer expired, send what we can and go into
 781: 	 * transmit state.
 782: 	 */
 783:     if (cb->s_force == 1 + SPPT_PERSIST) {
 784:         if (win != 0) {
 785:             cb->s_timer[SPPT_PERSIST] = 0;
 786:             cb->s_rxtshift = 0;
 787:         }
 788:     }
 789:     span = cb->s_seq - cb->s_rack;
 790:     len = MIN(span, win) - off;
 791: 
 792:     if (len < 0) {
 793:         /*
 794: 		 * Window shrank after we went into it.
 795: 		 * If window shrank to 0, cancel pending
 796: 		 * restransmission and pull s_snxt back
 797: 		 * to (closed) window.  We will enter persist
 798: 		 * state below.  If the widndow didn't close completely,
 799: 		 * just wait for an ACK.
 800: 		 */
 801:         len = 0;
 802:         if (win == 0) {
 803:             cb->s_timer[SPPT_REXMT] = 0;
 804:             cb->s_snxt = cb->s_rack;
 805:         }
 806:     }
 807:     if (len > 1)
 808:         sendalot = 1;
 809:     rcv_win = sbspace(&so->so_rcv);
 810: 
 811:     /*
 812: 	 * Send if we owe peer an ACK.
 813: 	 */
 814:     if (cb->s_oobflags & SF_SOOB) {
 815:         /*
 816: 		 * must transmit this out of band packet
 817: 		 */
 818:         cb->s_oobflags &= ~ SF_SOOB;
 819:         sendalot = 1;
 820:         sppstat.spps_sndurg++;
 821:         goto found;
 822:     }
 823:     if (cb->s_flags & SF_ACKNOW)
 824:         goto send;
 825:     if (cb->s_state < TCPS_ESTABLISHED)
 826:         goto send;
 827:     /*
 828: 	 * Silly window can't happen in spp.
 829: 	 * Code from tcp deleted.
 830: 	 */
 831:     if (len)
 832:         goto send;
 833:     /*
 834: 	 * Compare available window to amount of window
 835: 	 * known to peer (as advertised window less
 836: 	 * next expected input.)  If the difference is at least two
 837: 	 * packets or at least 35% of the mximum possible window,
 838: 	 * then want to send a window update to peer.
 839: 	 */
 840:     if (rcv_win > 0) {
 841:         u_short delta =  1 + cb->s_alo - cb->s_ack;
 842:         int adv = rcv_win - (delta * cb->s_mtu);
 843: 
 844:         if ((so->so_rcv.sb_cc == 0 && adv >= (2 * cb->s_mtu)) ||
 845:             (100 * adv / so->so_rcv.sb_hiwat >= 35)) {
 846:             sppstat.spps_sndwinup++;
 847:             cb->s_flags |= SF_ACKNOW;
 848:             goto send;
 849:         }
 850: 
 851:     }
 852:     /*
 853: 	 * Many comments from tcp_output.c are appropriate here
 854: 	 * including . . .
 855: 	 * If send window is too small, there is data to transmit, and no
 856: 	 * retransmit or persist is pending, then go to persist state.
 857: 	 * If nothing happens soon, send when timer expires:
 858: 	 * if window is nonzero, transmit what we can,
 859: 	 * otherwise send a probe.
 860: 	 */
 861:     if (so->so_snd.sb_cc && cb->s_timer[SPPT_REXMT] == 0 &&
 862:         cb->s_timer[SPPT_PERSIST] == 0) {
 863:             cb->s_rxtshift = 0;
 864:             spp_setpersist(cb);
 865:     }
 866:     /*
 867: 	 * No reason to send a packet, just return.
 868: 	 */
 869:     cb->s_outx = 1;
 870:     return (0);
 871: 
 872: send:
 873:     /*
 874: 	 * Find requested packet.
 875: 	 */
 876:     si = 0;
 877:     if (len > 0) {
 878:         cb->s_want = cb->s_snxt;
 879:         for (m = sb->sb_mb; m; m = m->m_act) {
 880:             si = mtod(m, struct spidp *);
 881:             if (SSEQ_LEQ(cb->s_snxt, si->si_seq))
 882:                 break;
 883:         }
 884:     found:
 885:         if (si) {
 886:             if (si->si_seq == cb->s_snxt)
 887:                     cb->s_snxt++;
 888:                 else
 889:                     sppstat.spps_sndvoid++, si = 0;
 890:         }
 891:     }
 892:     /*
 893: 	 * update window
 894: 	 */
 895:     if (rcv_win < 0)
 896:         rcv_win = 0;
 897:     alo = cb->s_ack - 1 + (rcv_win / ((short)cb->s_mtu));
 898:     if (SSEQ_LT(alo, cb->s_alo))
 899:         alo = cb->s_alo;
 900: 
 901:     if (si) {
 902:         /*
 903: 		 * must make a copy of this packet for
 904: 		 * idp_output to monkey with
 905: 		 */
 906:         m = m_copy(dtom(si), 0, (int)M_COPYALL);
 907:         if (m == NULL) {
 908:             return (ENOBUFS);
 909:         }
 910:         m0 = m;
 911:         si = mtod(m, struct spidp *);
 912:         if (SSEQ_LT(si->si_seq, cb->s_smax))
 913:             sppstat.spps_sndrexmitpack++;
 914:         else
 915:             sppstat.spps_sndpack++;
 916:     } else if (cb->s_force || cb->s_flags & SF_ACKNOW) {
 917:         /*
 918: 		 * Must send an acknowledgement or a probe
 919: 		 */
 920:         if (cb->s_force)
 921:             sppstat.spps_sndprobe++;
 922:         if (cb->s_flags & SF_ACKNOW)
 923:             sppstat.spps_sndacks++;
 924:         m = m_get(M_DONTWAIT, MT_HEADER);
 925:         if (m == 0) {
 926:             return (ENOBUFS);
 927:         }
 928:         /*
 929: 		 * Fill in mbuf with extended SP header
 930: 		 * and addresses and length put into network format.
 931: 		 * Allign beginning of packet to long to prepend
 932: 		 * ifp's on loopback, or NSIP encaspulation for fussy cpu's.
 933: 		 */
 934:         m->m_off = MMAXOFF - sizeof (struct spidp) - 2;
 935:         m->m_len = sizeof (*si);
 936:         m->m_next = 0;
 937:         si = mtod(m, struct spidp *);
 938:         si->si_i = *cb->s_idp;
 939:         si->si_s = cb->s_shdr;
 940:         si->si_seq = cb->s_smax + 1;
 941:         si->si_len = htons(sizeof (*si));
 942:         si->si_cc |= SP_SP;
 943:     } else {
 944:         cb->s_outx = 3;
 945:         if (so->so_options & SO_DEBUG || traceallspps)
 946:             spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
 947:         return (0);
 948:     }
 949:     /*
 950: 	 * Stuff checksum and output datagram.
 951: 	 */
 952:     if ((si->si_cc & SP_SP) == 0) {
 953:         if (cb->s_force != (1 + SPPT_PERSIST) ||
 954:             cb->s_timer[SPPT_PERSIST] == 0) {
 955:             /*
 956: 			 * If this is a new packet and we are not currently
 957: 			 * timing anything, time this one.
 958: 			 */
 959:             if (SSEQ_LT(cb->s_smax, si->si_seq)) {
 960:                 cb->s_smax = si->si_seq;
 961:                 if (cb->s_rtt == 0) {
 962:                     sppstat.spps_segstimed++;
 963:                     cb->s_rtseq = si->si_seq;
 964:                     cb->s_rtt = 1;
 965:                 }
 966:             }
 967:             /*
 968: 			 * Set rexmt timer if not currently set,
 969: 			 * Initial value for retransmit timer is smoothed
 970: 			 * round-trip time + 2 * round-trip time variance.
 971: 			 * Initialize shift counter which is used for backoff
 972: 			 * of retransmit time.
 973: 			 */
 974:             if (cb->s_timer[SPPT_REXMT] == 0 &&
 975:                 cb->s_snxt != cb->s_rack) {
 976:                 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
 977:                 if (cb->s_timer[SPPT_PERSIST]) {
 978:                     cb->s_timer[SPPT_PERSIST] = 0;
 979:                     cb->s_rxtshift = 0;
 980:                 }
 981:             }
 982:         } else if (SSEQ_LT(cb->s_smax, si->si_seq)) {
 983:             cb->s_smax = si->si_seq;
 984:         }
 985:     } else if (cb->s_state < TCPS_ESTABLISHED) {
 986:         if (cb->s_rtt == 0)
 987:             cb->s_rtt = 1; /* Time initial handshake */
 988:         if (cb->s_timer[SPPT_REXMT] == 0)
 989:             cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
 990:     }
 991:     {
 992:         /*
 993: 		 * Do not request acks when we ack their data packets or
 994: 		 * when we do a gratuitous window update.
 995: 		 */
 996:         if (((si->si_cc & SP_SP) == 0) || cb->s_force)
 997:                 si->si_cc |= SP_SA;
 998:         si->si_seq = htons(si->si_seq);
 999:         si->si_alo = htons(alo);
1000:         si->si_ack = htons(cb->s_ack);
1001: 
1002:         if (idpcksum) {
1003:             si->si_sum = 0;
1004:             len = ntohs(si->si_len);
1005:             if (len & 1)
1006:                 len++;
1007:             si->si_sum = ns_cksum(dtom(si), len);
1008:         } else
1009:             si->si_sum = 0xffff;
1010: 
1011:         cb->s_outx = 4;
1012:         if (so->so_options & SO_DEBUG || traceallspps)
1013:             spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
1014: 
1015:         if (so->so_options & SO_DONTROUTE)
1016:             error = ns_output(m, (struct route *)0, NS_ROUTETOIF);
1017:         else
1018:             error = ns_output(m, &cb->s_nspcb->nsp_route, 0);
1019:     }
1020:     if (error) {
1021:         return (error);
1022:     }
1023:     sppstat.spps_sndtotal++;
1024:     /*
1025: 	 * Data sent (as far as we can tell).
1026: 	 * If this advertises a larger window than any other segment,
1027: 	 * then remember the size of the advertized window.
1028: 	 * Any pending ACK has now been sent.
1029: 	 */
1030:     cb->s_force = 0;
1031:     cb->s_flags &= ~(SF_ACKNOW|SF_DELACK);
1032:     if (SSEQ_GT(alo, cb->s_alo))
1033:         cb->s_alo = alo;
1034:     if (sendalot)
1035:         goto again;
1036:     cb->s_outx = 5;
1037:     return (0);
1038: }
1039: 
1040: int spp_do_persist_panics = 0;
1041: 
1042: spp_setpersist(cb)
1043:     register struct sppcb *cb;
1044: {
1045:     register t = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
1046:     extern int spp_backoff[];
1047: 
1048:     if (cb->s_timer[SPPT_REXMT] && spp_do_persist_panics)
1049:         panic("spp_output REXMT");
1050:     /*
1051: 	 * Start/restart persistance timer.
1052: 	 */
1053:     SPPT_RANGESET(cb->s_timer[SPPT_PERSIST],
1054:         t*spp_backoff[cb->s_rxtshift],
1055:         SPPTV_PERSMIN, SPPTV_PERSMAX);
1056:     if (cb->s_rxtshift < SPP_MAXRXTSHIFT)
1057:         cb->s_rxtshift++;
1058: }
1059: /*ARGSUSED*/
1060: spp_ctloutput(req, so, level, name, value)
1061:     int req;
1062:     struct socket *so;
1063:     int name;
1064:     struct mbuf **value;
1065: {
1066:     register struct mbuf *m;
1067:     struct nspcb *nsp = sotonspcb(so);
1068:     register struct sppcb *cb;
1069:     int mask, error = 0;
1070: 
1071:     if (level != NSPROTO_SPP) {
1072:         /* This will have to be changed when we do more general
1073: 		   stacking of protocols */
1074:         return (idp_ctloutput(req, so, level, name, value));
1075:     }
1076:     if (nsp == NULL) {
1077:         error = EINVAL;
1078:         goto release;
1079:     } else
1080:         cb = nstosppcb(nsp);
1081: 
1082:     switch (req) {
1083: 
1084:     case PRCO_GETOPT:
1085:         if (value == NULL)
1086:             return (EINVAL);
1087:         m = m_get(M_DONTWAIT, MT_DATA);
1088:         if (m == NULL)
1089:             return (ENOBUFS);
1090:         switch (name) {
1091: 
1092:         case SO_HEADERS_ON_INPUT:
1093:             mask = SF_HI;
1094:             goto get_flags;
1095: 
1096:         case SO_HEADERS_ON_OUTPUT:
1097:             mask = SF_HO;
1098:         get_flags:
1099:             m->m_len = sizeof(short);
1100:             m->m_off = MMAXOFF - sizeof(short);
1101:             *mtod(m, short *) = cb->s_flags & mask;
1102:             break;
1103: 
1104:         case SO_MTU:
1105:             m->m_len = sizeof(u_short);
1106:             m->m_off = MMAXOFF - sizeof(short);
1107:             *mtod(m, short *) = cb->s_mtu;
1108:             break;
1109: 
1110:         case SO_LAST_HEADER:
1111:             m->m_len = sizeof(struct sphdr);
1112:             m->m_off = MMAXOFF - sizeof(struct sphdr);
1113:             *mtod(m, struct sphdr *) = cb->s_rhdr;
1114:             break;
1115: 
1116:         case SO_DEFAULT_HEADERS:
1117:             m->m_len = sizeof(struct spidp);
1118:             m->m_off = MMAXOFF - sizeof(struct sphdr);
1119:             *mtod(m, struct sphdr *) = cb->s_shdr;
1120:             break;
1121: 
1122:         default:
1123:             error = EINVAL;
1124:         }
1125:         *value = m;
1126:         break;
1127: 
1128:     case PRCO_SETOPT:
1129:         if (value == 0 || *value == 0) {
1130:             error = EINVAL;
1131:             break;
1132:         }
1133:         switch (name) {
1134:             int *ok;
1135: 
1136:         case SO_HEADERS_ON_INPUT:
1137:             mask = SF_HI;
1138:             goto set_head;
1139: 
1140:         case SO_HEADERS_ON_OUTPUT:
1141:             mask = SF_HO;
1142:         set_head:
1143:             if (cb->s_flags & SF_PI) {
1144:                 ok = mtod(*value, int *);
1145:                 if (*ok)
1146:                     cb->s_flags |= mask;
1147:                 else
1148:                     cb->s_flags &= ~mask;
1149:             } else error = EINVAL;
1150:             break;
1151: 
1152:         case SO_MTU:
1153:             cb->s_mtu = *(mtod(*value, u_short *));
1154:             break;
1155: 
1156:         case SO_DEFAULT_HEADERS:
1157:             {
1158:                 register struct sphdr *sp
1159:                         = mtod(*value, struct sphdr *);
1160:                 cb->s_dt = sp->sp_dt;
1161:                 cb->s_cc = sp->sp_cc & SP_EM;
1162:             }
1163:             break;
1164: 
1165:         default:
1166:             error = EINVAL;
1167:         }
1168:         m_freem(*value);
1169:         break;
1170:     }
1171:     release:
1172:         return (error);
1173: }
1174: 
1175: /*ARGSUSED*/
1176: spp_usrreq(so, req, m, nam, rights)
1177:     struct socket *so;
1178:     int req;
1179:     struct mbuf *m, *nam, *rights;
1180: {
1181:     struct nspcb *nsp = sotonspcb(so);
1182:     register struct sppcb *cb;
1183:     int s = splnet();
1184:     int error = 0, ostate;
1185:     struct mbuf *mm;
1186:     register struct sockbuf *sb;
1187: 
1188:     if (req == PRU_CONTROL)
1189:                 return (ns_control(so, (int)m, (caddr_t)nam,
1190:             (struct ifnet *)rights));
1191:     if (rights && rights->m_len) {
1192:         error = EINVAL;
1193:         goto release;
1194:     }
1195:     if (nsp == NULL) {
1196:         if (req != PRU_ATTACH) {
1197:             error = EINVAL;
1198:             goto release;
1199:         }
1200:     } else
1201:         cb = nstosppcb(nsp);
1202: 
1203:     ostate = cb ? cb->s_state : 0;
1204: 
1205:     switch (req) {
1206: 
1207:     case PRU_ATTACH:
1208:         if (nsp != NULL) {
1209:             error = EISCONN;
1210:             break;
1211:         }
1212:         error = ns_pcballoc(so, &nspcb);
1213:         if (error)
1214:             break;
1215:         error = soreserve(so, 3072, 3072);
1216:         if (error)
1217:             break;
1218:         nsp = sotonspcb(so);
1219: 
1220:         mm = m_getclr(M_DONTWAIT, MT_PCB);
1221:         sb = &so->so_snd;
1222: 
1223:         if (mm == NULL) {
1224:             error = ENOBUFS;
1225:             break;
1226:         }
1227:         cb = mtod(mm, struct sppcb *);
1228:         mm = m_getclr(M_DONTWAIT, MT_HEADER);
1229:         if (mm == NULL) {
1230:             m_free(dtom(m));
1231:             error = ENOBUFS;
1232:             break;
1233:         }
1234:         cb->s_idp = mtod(mm, struct idp *);
1235:         cb->s_state = TCPS_LISTEN;
1236:         cb->s_smax = -1;
1237:         cb->s_swl1 = -1;
1238:         cb->s_q.si_next = cb->s_q.si_prev = &cb->s_q;
1239:         cb->s_nspcb = nsp;
1240:         cb->s_mtu = 576 - sizeof (struct spidp);
1241:         cb->s_cwnd = sbspace(sb) * CUNIT / cb->s_mtu;
1242:         cb->s_ssthresh = cb->s_cwnd;
1243:         cb->s_cwmx = sb->sb_mbmax * CUNIT /
1244:                 (2 * sizeof (struct spidp));
1245:         /* Above is recomputed when connecting to account
1246: 		   for changed buffering or mtu's */
1247:         cb->s_rtt = SPPTV_SRTTBASE;
1248:         cb->s_rttvar = SPPTV_SRTTDFLT << 2;
1249:         SPPT_RANGESET(cb->s_rxtcur,
1250:             ((SPPTV_SRTTBASE >> 2) + (SPPTV_SRTTDFLT << 2)) >> 1,
1251:             SPPTV_MIN, SPPTV_REXMTMAX);
1252:         nsp->nsp_pcb = (caddr_t) cb;
1253:         break;
1254: 
1255:     case PRU_DETACH:
1256:         if (nsp == NULL) {
1257:             error = ENOTCONN;
1258:             break;
1259:         }
1260:         if (cb->s_state > TCPS_LISTEN)
1261:             cb = spp_disconnect(cb);
1262:         else
1263:             cb = spp_close(cb);
1264:         break;
1265: 
1266:     case PRU_BIND:
1267:         error = ns_pcbbind(nsp, nam);
1268:         break;
1269: 
1270:     case PRU_LISTEN:
1271:         if (nsp->nsp_lport == 0)
1272:             error = ns_pcbbind(nsp, (struct mbuf *)0);
1273:         if (error == 0)
1274:             cb->s_state = TCPS_LISTEN;
1275:         break;
1276: 
1277:     /*
1278: 	 * Initiate connection to peer.
1279: 	 * Enter SYN_SENT state, and mark socket as connecting.
1280: 	 * Start keep-alive timer, setup prototype header,
1281: 	 * Send initial system packet requesting connection.
1282: 	 */
1283:     case PRU_CONNECT:
1284:         if (nsp->nsp_lport == 0) {
1285:             error = ns_pcbbind(nsp, (struct mbuf *)0);
1286:             if (error)
1287:                 break;
1288:         }
1289:         error = ns_pcbconnect(nsp, nam);
1290:         if (error)
1291:             break;
1292:         soisconnecting(so);
1293:         sppstat.spps_connattempt++;
1294:         cb->s_state = TCPS_SYN_SENT;
1295:         cb->s_did = 0;
1296:         spp_template(cb);
1297:         cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
1298:         cb->s_force = 1 + SPPTV_KEEP;
1299:         /*
1300: 		 * Other party is required to respond to
1301: 		 * the port I send from, but he is not
1302: 		 * required to answer from where I am sending to,
1303: 		 * so allow wildcarding.
1304: 		 * original port I am sending to is still saved in
1305: 		 * cb->s_dport.
1306: 		 */
1307:         nsp->nsp_fport = 0;
1308:         error = spp_output(cb, (struct mbuf *) 0);
1309:         break;
1310: 
1311:     case PRU_CONNECT2:
1312:         error = EOPNOTSUPP;
1313:         break;
1314: 
1315:     /*
1316: 	 * We may decide later to implement connection closing
1317: 	 * handshaking at the spp level optionally.
1318: 	 * here is the hook to do it:
1319: 	 */
1320:     case PRU_DISCONNECT:
1321:         cb = spp_disconnect(cb);
1322:         break;
1323: 
1324:     /*
1325: 	 * Accept a connection.  Essentially all the work is
1326: 	 * done at higher levels; just return the address
1327: 	 * of the peer, storing through addr.
1328: 	 */
1329:     case PRU_ACCEPT: {
1330:         struct sockaddr_ns *sns = mtod(nam, struct sockaddr_ns *);
1331: 
1332:         nam->m_len = sizeof (struct sockaddr_ns);
1333:         sns->sns_family = AF_NS;
1334:         sns->sns_addr = nsp->nsp_faddr;
1335:         break;
1336:         }
1337: 
1338:     case PRU_SHUTDOWN:
1339:         socantsendmore(so);
1340:         cb = spp_usrclosed(cb);
1341:         if (cb)
1342:             error = spp_output(cb, (struct mbuf *) 0);
1343:         break;
1344: 
1345:     /*
1346: 	 * After a receive, possibly send acknowledgment
1347: 	 * updating allocation.
1348: 	 */
1349:     case PRU_RCVD:
1350:         cb->s_flags |= SF_RVD;
1351:         (void) spp_output(cb, (struct mbuf *) 0);
1352:         cb->s_flags &= ~SF_RVD;
1353:         break;
1354: 
1355:     case PRU_ABORT:
1356:         (void) spp_drop(cb, ECONNABORTED);
1357:         break;
1358: 
1359:     case PRU_SENSE:
1360:     case PRU_CONTROL:
1361:         m = NULL;
1362:         error = EOPNOTSUPP;
1363:         break;
1364: 
1365:     case PRU_RCVOOB:
1366:         if ((cb->s_oobflags & SF_IOOB) || so->so_oobmark ||
1367:             (so->so_state & SS_RCVATMARK)) {
1368:             m->m_len = 1;
1369:             *mtod(m, caddr_t) = cb->s_iobc;
1370:             break;
1371:         }
1372:         error = EINVAL;
1373:         break;
1374: 
1375:     case PRU_SENDOOB:
1376:         if (sbspace(&so->so_snd) < -512) {
1377:             error = ENOBUFS;
1378:             break;
1379:         }
1380:         cb->s_oobflags |= SF_SOOB;
1381:         /* fall into */
1382:     case PRU_SEND:
1383:         error = spp_output(cb, m);
1384:         m = NULL;
1385:         break;
1386: 
1387:     case PRU_SOCKADDR:
1388:         ns_setsockaddr(nsp, nam);
1389:         break;
1390: 
1391:     case PRU_PEERADDR:
1392:         ns_setpeeraddr(nsp, nam);
1393:         break;
1394: 
1395:     case PRU_SLOWTIMO:
1396:         cb = spp_timers(cb, (int)nam);
1397:         req |= ((int)nam) << 8;
1398:         break;
1399: 
1400:     case PRU_FASTTIMO:
1401:     case PRU_PROTORCV:
1402:     case PRU_PROTOSEND:
1403:         error =  EOPNOTSUPP;
1404:         break;
1405: 
1406:     default:
1407:         panic("sp_usrreq");
1408:     }
1409:     if (cb && (so->so_options & SO_DEBUG || traceallspps))
1410:         spp_trace(SA_USER, (u_char)ostate, cb, (struct spidp *)0, req);
1411: release:
1412:     if (m != NULL)
1413:         m_freem(m);
1414:     splx(s);
1415:     return (error);
1416: }
1417: 
1418: spp_usrreq_sp(so, req, m, nam, rights)
1419:     struct socket *so;
1420:     int req;
1421:     struct mbuf *m, *nam, *rights;
1422: {
1423:     int error = spp_usrreq(so, req, m, nam, rights);
1424: 
1425:     if (req == PRU_ATTACH && error == 0) {
1426:         struct nspcb *nsp = sotonspcb(so);
1427:         ((struct sppcb *)nsp->nsp_pcb)->s_flags |=
1428:                     (SF_HI | SF_HO | SF_PI);
1429:     }
1430:     return (error);
1431: }
1432: 
1433: /*
1434:  * Create template to be used to send spp packets on a connection.
1435:  * Called after host entry created, fills
1436:  * in a skeletal spp header (choosing connection id),
1437:  * minimizing the amount of work necessary when the connection is used.
1438:  */
1439: spp_template(cb)
1440:     register struct sppcb *cb;
1441: {
1442:     register struct nspcb *nsp = cb->s_nspcb;
1443:     register struct idp *idp = cb->s_idp;
1444:     register struct sockbuf *sb = &(nsp->nsp_socket->so_snd);
1445: 
1446:     idp->idp_pt = NSPROTO_SPP;
1447:     idp->idp_sna = nsp->nsp_laddr;
1448:     idp->idp_dna = nsp->nsp_faddr;
1449:     cb->s_sid = htons(spp_iss);
1450:     spp_iss += SPP_ISSINCR/2;
1451:     cb->s_alo = 1;
1452:     cb->s_cwnd = (sbspace(sb) * CUNIT) / cb->s_mtu;
1453:     cb->s_ssthresh = cb->s_cwnd; /* Try to expand fast to full complement
1454: 					of large packets */
1455:     cb->s_cwmx = (sb->sb_mbmax * CUNIT) / (2 * sizeof(struct spidp));
1456:     cb->s_cwmx = MAX(cb->s_cwmx, cb->s_cwnd);
1457:         /* But allow for lots of little packets as well */
1458: }
1459: 
1460: /*
1461:  * Close a SPIP control block:
1462:  *	discard spp control block itself
1463:  *	discard ns protocol control block
1464:  *	wake up any sleepers
1465:  */
1466: struct sppcb *
1467: spp_close(cb)
1468:     register struct sppcb *cb;
1469: {
1470:     register struct spidp_q *s;
1471:     struct nspcb *nsp = cb->s_nspcb;
1472:     struct socket *so = nsp->nsp_socket;
1473:     register struct mbuf *m;
1474: 
1475:     s = cb->s_q.si_next;
1476:     while (s != &(cb->s_q)) {
1477:         s = s->si_next;
1478:         m = dtom(s->si_prev);
1479:         remque(s->si_prev);
1480:         m_freem(m);
1481:     }
1482:     (void) m_free(dtom(cb->s_idp));
1483:     (void) m_free(dtom(cb));
1484:     nsp->nsp_pcb = 0;
1485:     soisdisconnected(so);
1486:     ns_pcbdetach(nsp);
1487:     sppstat.spps_closed++;
1488:     return ((struct sppcb *)0);
1489: }
1490: /*
1491:  *	Someday we may do level 3 handshaking
1492:  *	to close a connection or send a xerox style error.
1493:  *	For now, just close.
1494:  */
1495: struct sppcb *
1496: spp_usrclosed(cb)
1497:     register struct sppcb *cb;
1498: {
1499:     return (spp_close(cb));
1500: }
1501: struct sppcb *
1502: spp_disconnect(cb)
1503:     register struct sppcb *cb;
1504: {
1505:     return (spp_close(cb));
1506: }
1507: /*
1508:  * Drop connection, reporting
1509:  * the specified error.
1510:  */
1511: struct sppcb *
1512: spp_drop(cb, errno)
1513:     register struct sppcb *cb;
1514:     int errno;
1515: {
1516:     struct socket *so = cb->s_nspcb->nsp_socket;
1517: 
1518:     /*
1519: 	 * someday, in the xerox world
1520: 	 * we will generate error protocol packets
1521: 	 * announcing that the socket has gone away.
1522: 	 */
1523:     if (TCPS_HAVERCVDSYN(cb->s_state)) {
1524:         sppstat.spps_drops++;
1525:         cb->s_state = TCPS_CLOSED;
1526:         /*(void) tcp_output(cb);*/
1527:     } else
1528:         sppstat.spps_conndrops++;
1529:     so->so_error = errno;
1530:     return (spp_close(cb));
1531: }
1532: 
1533: spp_abort(nsp)
1534:     struct nspcb *nsp;
1535: {
1536: 
1537:     (void) spp_close((struct sppcb *)nsp->nsp_pcb);
1538: }
1539: 
1540: int spp_backoff[SPP_MAXRXTSHIFT+1] =
1541:     { 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 };
1542: /*
1543:  * Fast timeout routine for processing delayed acks
1544:  */
1545: spp_fasttimo()
1546: {
1547:     register struct nspcb *nsp;
1548:     register struct sppcb *cb;
1549:     int s = splnet();
1550: 
1551:     nsp = nspcb.nsp_next;
1552:     if (nsp)
1553:     for (; nsp != &nspcb; nsp = nsp->nsp_next)
1554:         if ((cb = (struct sppcb *)nsp->nsp_pcb) &&
1555:             (cb->s_flags & SF_DELACK)) {
1556:             cb->s_flags &= ~SF_DELACK;
1557:             cb->s_flags |= SF_ACKNOW;
1558:             sppstat.spps_delack++;
1559:             (void) spp_output(cb, (struct mbuf *) 0);
1560:         }
1561:     splx(s);
1562: }
1563: 
1564: /*
1565:  * spp protocol timeout routine called every 500 ms.
1566:  * Updates the timers in all active pcb's and
1567:  * causes finite state machine actions if timers expire.
1568:  */
1569: spp_slowtimo()
1570: {
1571:     register struct nspcb *ip, *ipnxt;
1572:     register struct sppcb *cb;
1573:     int s = splnet();
1574:     register int i;
1575: 
1576:     /*
1577: 	 * Search through tcb's and update active timers.
1578: 	 */
1579:     ip = nspcb.nsp_next;
1580:     if (ip == 0) {
1581:         splx(s);
1582:         return;
1583:     }
1584:     while (ip != &nspcb) {
1585:         cb = nstosppcb(ip);
1586:         ipnxt = ip->nsp_next;
1587:         if (cb == 0)
1588:             goto tpgone;
1589:         for (i = 0; i < SPPT_NTIMERS; i++) {
1590:             if (cb->s_timer[i] && --cb->s_timer[i] == 0) {
1591:                 (void) spp_usrreq(cb->s_nspcb->nsp_socket,
1592:                     PRU_SLOWTIMO, (struct mbuf *)0,
1593:                     (struct mbuf *)i, (struct mbuf *)0);
1594:                 if (ipnxt->nsp_prev != ip)
1595:                     goto tpgone;
1596:             }
1597:         }
1598:         cb->s_idle++;
1599:         if (cb->s_rtt)
1600:             cb->s_rtt++;
1601: tpgone:
1602:         ip = ipnxt;
1603:     }
1604:     spp_iss += SPP_ISSINCR/PR_SLOWHZ;       /* increment iss */
1605:     splx(s);
1606: }
1607: /*
1608:  * SPP timer processing.
1609:  */
1610: struct sppcb *
1611: spp_timers(cb, timer)
1612:     register struct sppcb *cb;
1613:     int timer;
1614: {
1615:     long rexmt;
1616:     int win;
1617: 
1618:     cb->s_force = 1 + timer;
1619:     switch (timer) {
1620: 
1621:     /*
1622: 	 * 2 MSL timeout in shutdown went off.  TCP deletes connection
1623: 	 * control block.
1624: 	 */
1625:     case SPPT_2MSL:
1626:         printf("spp: SPPT_2MSL went off for no reason\n");
1627:         cb->s_timer[timer] = 0;
1628:         break;
1629: 
1630:     /*
1631: 	 * Retransmission timer went off.  Message has not
1632: 	 * been acked within retransmit interval.  Back off
1633: 	 * to a longer retransmit interval and retransmit one packet.
1634: 	 */
1635:     case SPPT_REXMT:
1636:         if (++cb->s_rxtshift > SPP_MAXRXTSHIFT) {
1637:             cb->s_rxtshift = SPP_MAXRXTSHIFT;
1638:             sppstat.spps_timeoutdrop++;
1639:             cb = spp_drop(cb, ETIMEDOUT);
1640:             break;
1641:         }
1642:         sppstat.spps_rexmttimeo++;
1643:         rexmt = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
1644:         rexmt *= spp_backoff[cb->s_rxtshift];
1645:         SPPT_RANGESET(cb->s_rxtcur, rexmt, SPPTV_MIN, SPPTV_REXMTMAX);
1646:         cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1647:         /*
1648: 		 * If we have backed off fairly far, our srtt
1649: 		 * estimate is probably bogus.  Clobber it
1650: 		 * so we'll take the next rtt measurement as our srtt;
1651: 		 * move the current srtt into rttvar to keep the current
1652: 		 * retransmit times until then.
1653: 		 */
1654:         if (cb->s_rxtshift > SPP_MAXRXTSHIFT / 4 ) {
1655:             cb->s_rttvar += (cb->s_srtt >> 2);
1656:             cb->s_srtt = 0;
1657:         }
1658:         cb->s_snxt = cb->s_rack;
1659:         /*
1660: 		 * If timing a packet, stop the timer.
1661: 		 */
1662:         cb->s_rtt = 0;
1663:         /*
1664: 		 * See very long discussion in tcp_timer.c about congestion
1665: 		 * window and sstrhesh
1666: 		 */
1667:         win = MIN(cb->s_swnd, (cb->s_cwnd/CUNIT)) / 2;
1668:         if (win < 2)
1669:             win = 2;
1670:         cb->s_cwnd = CUNIT;
1671:         cb->s_ssthresh = win * CUNIT;
1672:         (void) spp_output(cb, (struct mbuf *) 0);
1673:         break;
1674: 
1675:     /*
1676: 	 * Persistance timer into zero window.
1677: 	 * Force a probe to be sent.
1678: 	 */
1679:     case SPPT_PERSIST:
1680:         sppstat.spps_persisttimeo++;
1681:         spp_setpersist(cb);
1682:         (void) spp_output(cb, (struct mbuf *) 0);
1683:         break;
1684: 
1685:     /*
1686: 	 * Keep-alive timer went off; send something
1687: 	 * or drop connection if idle for too long.
1688: 	 */
1689:     case SPPT_KEEP:
1690:         sppstat.spps_keeptimeo++;
1691:         if (cb->s_state < TCPS_ESTABLISHED)
1692:             goto dropit;
1693:         if (cb->s_nspcb->nsp_socket->so_options & SO_KEEPALIVE) {
1694:                 if (cb->s_idle >= SPPTV_MAXIDLE)
1695:                 goto dropit;
1696:             sppstat.spps_keepprobe++;
1697:             (void) spp_output(cb, (struct mbuf *) 0);
1698:         } else
1699:             cb->s_idle = 0;
1700:         cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
1701:         break;
1702:     dropit:
1703:         sppstat.spps_keepdrops++;
1704:         cb = spp_drop(cb, ETIMEDOUT);
1705:         break;
1706:     }
1707:     return (cb);
1708: }
1709: #ifndef lint
1710: int SppcbSize = sizeof (struct sppcb);
1711: int NspcbSize = sizeof (struct nspcb);
1712: #endif lint
1713: #endif

Defined functions

Defined variables

Defined macros