2 * Copyright (c) 1984, 1985, 1986, 1987, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
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 $
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/malloc.h>
41 #include <sys/protosw.h>
42 #include <sys/socket.h>
43 #include <sys/socketvar.h>
44 #include <sys/errno.h>
47 #include <net/route.h>
48 #include <netinet/tcp_fsm.h>
51 #include <netns/ns_pcb.h>
52 #include <netns/idp.h>
53 #include <netns/idp_var.h>
54 #include <netns/ns_error.h>
56 #include <netns/spidp.h>
57 #include <netns/spp_timer.h>
58 #include <netns/spp_var.h>
59 #include <netns/spp_debug.h>
62 * SP protocol implementation.
67 spp_iss = 1; /* WRONG !! should fish it out of TODR */
69 struct spidp spp_savesi;
71 extern int sppconsdebug;
73 int spp_use_delack = 0;
74 u_short spp_newchecks[50];
78 register struct mbuf *m;
79 register struct nspcb *nsp;
81 register struct sppcb *cb;
82 register struct spidp *si = mtod(m, struct spidp *);
83 register struct socket *so;
88 sppstat.spps_rcvtotal++;
90 panic("No nspcb in spp_input");
95 if (cb == 0) goto bad;
97 if (m->m_len < sizeof(*si)) {
98 if ((m = m_pullup(m, sizeof(*si))) == 0) {
99 sppstat.spps_rcvshort++;
102 si = mtod(m, struct spidp *);
104 si->si_seq = ntohs(si->si_seq);
105 si->si_ack = ntohs(si->si_ack);
106 si->si_alo = ntohs(si->si_alo);
108 so = nsp->nsp_socket;
109 if (so->so_options & SO_DEBUG || traceallspps) {
110 ostate = cb->s_state;
113 if (so->so_options & SO_ACCEPTCONN) {
114 struct sppcb *ocb = cb;
116 so = sonewconn(so, 0);
121 * This is ugly, but ....
123 * Mark socket as temporary until we're
124 * committed to keeping it. The code at
125 * ``drop'' and ``dropwithreset'' check the
126 * flag dropsocket to see if the temporary
127 * socket created here should be discarded.
128 * We mark the socket as discardable until
129 * we're committed to it below in TCPS_LISTEN.
132 nsp = (struct nspcb *)so->so_pcb;
133 nsp->nsp_laddr = si->si_dna;
135 cb->s_mtu = ocb->s_mtu; /* preserve sockopts */
136 cb->s_flags = ocb->s_flags; /* preserve sockopts */
137 cb->s_flags2 = ocb->s_flags2; /* preserve sockopts */
138 cb->s_state = TCPS_LISTEN;
142 * Packet received on connection.
143 * reset idle time and keep-alive timer;
146 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
148 switch (cb->s_state) {
152 register struct sockaddr_ns *sns;
153 struct ns_addr laddr;
156 * If somebody here was carying on a conversation
157 * and went away, and his pen pal thinks he can
158 * still talk, we get the misdirected packet.
160 if (spp_hardnosed && (si->si_did != 0 || si->si_seq != 0)) {
164 am = m_get(M_DONTWAIT, MT_SONAME);
167 am->m_len = sizeof (struct sockaddr_ns);
168 sns = mtod(am, struct sockaddr_ns *);
169 sns->sns_len = sizeof(*sns);
170 sns->sns_family = AF_NS;
171 sns->sns_addr = si->si_sna;
172 laddr = nsp->nsp_laddr;
173 if (ns_nullhost(laddr))
174 nsp->nsp_laddr = si->si_dna;
175 if (ns_pcbconnect(nsp, am)) {
176 nsp->nsp_laddr = laddr;
183 dropsocket = 0; /* committed to socket */
184 cb->s_did = si->si_sid;
185 cb->s_rack = si->si_ack;
186 cb->s_ralo = si->si_alo;
187 #define THREEWAYSHAKE
189 cb->s_state = TCPS_SYN_RECEIVED;
190 cb->s_force = 1 + SPPT_KEEP;
191 sppstat.spps_accepts++;
192 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
196 * This state means that we have heard a response
197 * to our acceptance of their connection
198 * It is probably logically unnecessary in this
201 case TCPS_SYN_RECEIVED: {
202 if (si->si_did!=cb->s_sid) {
207 nsp->nsp_fport = si->si_sport;
208 cb->s_timer[SPPT_REXMT] = 0;
209 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
211 cb->s_state = TCPS_ESTABLISHED;
212 sppstat.spps_accepts++;
217 * This state means that we have gotten a response
218 * to our attempt to establish a connection.
219 * We fill in the data from the other side,
220 * telling us which port to respond to, instead of the well-
221 * known one we might have sent to in the first place.
222 * We also require that this is a response to our
226 if (si->si_did!=cb->s_sid) {
230 sppstat.spps_connects++;
231 cb->s_did = si->si_sid;
232 cb->s_rack = si->si_ack;
233 cb->s_ralo = si->si_alo;
234 cb->s_dport = nsp->nsp_fport = si->si_sport;
235 cb->s_timer[SPPT_REXMT] = 0;
236 cb->s_flags |= SF_ACKNOW;
238 cb->s_state = TCPS_ESTABLISHED;
239 /* Use roundtrip time of connection request for initial rtt */
241 cb->s_srtt = cb->s_rtt << 3;
242 cb->s_rttvar = cb->s_rtt << 1;
243 SPPT_RANGESET(cb->s_rxtcur,
244 ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
245 SPPTV_MIN, SPPTV_REXMTMAX);
249 if (so->so_options & SO_DEBUG || traceallspps)
250 spp_trace(SA_INPUT, (u_char)ostate, cb, &spp_savesi, 0);
252 m->m_len -= sizeof (struct idp);
253 m->m_pkthdr.len -= sizeof (struct idp);
254 m->m_data += sizeof (struct idp);
256 if (spp_reass(cb, si)) {
259 if (cb->s_force || (cb->s_flags & (SF_ACKNOW|SF_WIN|SF_RXT)))
260 (void) spp_output(cb, (struct mbuf *)0);
261 cb->s_flags &= ~(SF_WIN|SF_RXT);
267 si->si_seq = ntohs(si->si_seq);
268 si->si_ack = ntohs(si->si_ack);
269 si->si_alo = ntohs(si->si_alo);
270 ns_error(dtom(si), NS_ERR_NOSOCK, 0);
271 if (cb->s_nspcb->nsp_socket->so_options & SO_DEBUG || traceallspps)
272 spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);
277 if (cb == 0 || cb->s_nspcb->nsp_socket->so_options & SO_DEBUG ||
279 spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);
283 int spprexmtthresh = 3;
286 * This is structurally similar to the tcp reassembly routine
287 * but its function is somewhat different: It merely queues
288 * packets up, and suppresses duplicates.
291 register struct sppcb *cb;
292 register struct spidp *si;
294 register struct spidp_q *q;
295 register struct mbuf *m;
296 register struct socket *so = cb->s_nspcb->nsp_socket;
297 char packetp = cb->s_flags & SF_HI;
304 * Update our news from them.
306 if (si->si_cc & SP_SA)
307 cb->s_flags |= (spp_use_delack ? SF_DELACK : SF_ACKNOW);
308 if (SSEQ_GT(si->si_alo, cb->s_ralo))
309 cb->s_flags |= SF_WIN;
310 if (SSEQ_LEQ(si->si_ack, cb->s_rack)) {
311 if ((si->si_cc & SP_SP) && cb->s_rack != (cb->s_smax + 1)) {
312 sppstat.spps_rcvdupack++;
314 * If this is a completely duplicate ack
315 * and other conditions hold, we assume
316 * a packet has been dropped and retransmit
317 * it exactly as in tcp_input().
319 if (si->si_ack != cb->s_rack ||
320 si->si_alo != cb->s_ralo)
322 else if (++cb->s_dupacks == spprexmtthresh) {
323 u_short onxt = cb->s_snxt;
324 int cwnd = cb->s_cwnd;
326 cb->s_snxt = si->si_ack;
328 cb->s_force = 1 + SPPT_REXMT;
329 (void) spp_output(cb, (struct mbuf *)0);
330 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
332 if (cwnd >= 4 * CUNIT)
333 cb->s_cwnd = cwnd / 2;
334 if (SSEQ_GT(onxt, cb->s_snxt))
344 * If our correspondent acknowledges data we haven't sent
345 * TCP would drop the packet after acking. We'll be a little
348 if (SSEQ_GT(si->si_ack, (cb->s_smax + 1))) {
349 sppstat.spps_rcvacktoomuch++;
350 si->si_ack = cb->s_smax + 1;
352 sppstat.spps_rcvackpack++;
354 * If transmit timer is running and timed sequence
355 * number was acked, update smoothed round trip time.
356 * See discussion of algorithm in tcp_input.c
358 if (cb->s_rtt && SSEQ_GT(si->si_ack, cb->s_rtseq)) {
359 sppstat.spps_rttupdated++;
360 if (cb->s_srtt != 0) {
361 register short delta;
362 delta = cb->s_rtt - (cb->s_srtt >> 3);
363 if ((cb->s_srtt += delta) <= 0)
367 delta -= (cb->s_rttvar >> 2);
368 if ((cb->s_rttvar += delta) <= 0)
372 * No rtt measurement yet
374 cb->s_srtt = cb->s_rtt << 3;
375 cb->s_rttvar = cb->s_rtt << 1;
379 SPPT_RANGESET(cb->s_rxtcur,
380 ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
381 SPPTV_MIN, SPPTV_REXMTMAX);
384 * If all outstanding data is acked, stop retransmit
385 * timer and remember to restart (more output or persist).
386 * If there is more data to be acked, restart retransmit
387 * timer, using current (possibly backed-off) value;
389 if (si->si_ack == cb->s_smax + 1) {
390 cb->s_timer[SPPT_REXMT] = 0;
391 cb->s_flags |= SF_RXT;
392 } else if (cb->s_timer[SPPT_PERSIST] == 0)
393 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
395 * When new data is acked, open the congestion window.
396 * If the window gives us less than ssthresh packets
397 * in flight, open exponentially (maxseg at a time).
398 * Otherwise open linearly (maxseg^2 / cwnd at a time).
401 if (cb->s_cwnd > cb->s_ssthresh)
402 incr = max(incr * incr / cb->s_cwnd, 1);
403 cb->s_cwnd = min(cb->s_cwnd + incr, cb->s_cwmx);
405 * Trim Acked data from output queue.
407 while ((m = so->so_snd.sb_mb) != NULL) {
408 if (SSEQ_LT((mtod(m, struct spidp *))->si_seq, si->si_ack))
409 sbdroprecord(&so->so_snd);
414 cb->s_rack = si->si_ack;
416 if (SSEQ_LT(cb->s_snxt, cb->s_rack))
417 cb->s_snxt = cb->s_rack;
418 if (SSEQ_LT(cb->s_swl1, si->si_seq) || cb->s_swl1 == si->si_seq &&
419 (SSEQ_LT(cb->s_swl2, si->si_ack) ||
420 cb->s_swl2 == si->si_ack && SSEQ_LT(cb->s_ralo, si->si_alo))) {
421 /* keep track of pure window updates */
422 if ((si->si_cc & SP_SP) && cb->s_swl2 == si->si_ack
423 && SSEQ_LT(cb->s_ralo, si->si_alo)) {
424 sppstat.spps_rcvwinupd++;
425 sppstat.spps_rcvdupack--;
427 cb->s_ralo = si->si_alo;
428 cb->s_swl1 = si->si_seq;
429 cb->s_swl2 = si->si_ack;
430 cb->s_swnd = (1 + si->si_alo - si->si_ack);
431 if (cb->s_swnd > cb->s_smxw)
432 cb->s_smxw = cb->s_swnd;
433 cb->s_flags |= SF_WIN;
436 * If this packet number is higher than that which
437 * we have allocated refuse it, unless urgent
439 if (SSEQ_GT(si->si_seq, cb->s_alo)) {
440 if (si->si_cc & SP_SP) {
441 sppstat.spps_rcvwinprobe++;
444 sppstat.spps_rcvpackafterwin++;
445 if (si->si_cc & SP_OB) {
446 if (SSEQ_GT(si->si_seq, cb->s_alo + 60)) {
447 ns_error(dtom(si), NS_ERR_FULLUP, 0);
449 } /* else queue this packet; */
451 /*register struct socket *so = cb->s_nspcb->nsp_socket;
452 if (so->so_state && SS_NOFDREF) {
453 ns_error(dtom(si), NS_ERR_NOSOCK, 0);
458 ns_error(dtom(si), NS_ERR_FULLUP, 0);
463 * If this is a system packet, we don't need to
464 * queue it up, and won't update acknowledge #
466 if (si->si_cc & SP_SP) {
470 * We have already seen this packet, so drop.
472 if (SSEQ_LT(si->si_seq, cb->s_ack)) {
474 sppstat.spps_rcvduppack++;
475 if (si->si_seq == cb->s_ack - 1)
480 * Loop through all packets queued up to insert in
481 * appropriate sequence.
483 for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
484 if (si->si_seq == SI(q)->si_seq) {
485 sppstat.spps_rcvduppack++;
488 if (SSEQ_LT(si->si_seq, SI(q)->si_seq)) {
489 sppstat.spps_rcvoopack++;
493 insque(si, q->si_prev);
495 * If this packet is urgent, inform process
497 if (si->si_cc & SP_OB) {
498 cb->s_iobc = ((char *)si)[1 + sizeof(*si)];
500 cb->s_oobflags |= SF_IOOB;
503 #define SPINC sizeof(struct sphdr)
505 * Loop through all packets queued up to update acknowledge
506 * number, and present all acknowledged data to user;
507 * If in packet interface mode, show packet headers.
509 for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
510 if (SI(q)->si_seq == cb->s_ack) {
513 if (SI(q)->si_cc & SP_OB) {
514 cb->s_oobflags &= ~SF_IOOB;
515 if (so->so_rcv.sb_cc)
516 so->so_oobmark = so->so_rcv.sb_cc;
518 so->so_state |= SS_RCVATMARK;
523 sppstat.spps_rcvpack++;
525 if (cb->s_flags2 & SF_NEWCALL) {
526 struct sphdr *sp = mtod(m, struct sphdr *);
527 u_char dt = sp->sp_dt;
529 if (dt != cb->s_rhdr.sp_dt) {
531 m_getclr(M_DONTWAIT, MT_CONTROL);
536 cb->s_rhdr.sp_dt = dt;
537 mm->m_len = 5; /*XXX*/
540 *(u_char *)(&s[2]) = dt;
541 sbappend(&so->so_rcv, mm);
544 if (sp->sp_cc & SP_OB) {
545 MCHTYPE(m, MT_OOBDATA);
548 so->so_state &= ~SS_RCVATMARK;
553 m->m_pkthdr.len -= SPINC;
555 if ((sp->sp_cc & SP_EM) || packetp) {
556 sbappendrecord(&so->so_rcv, m);
559 sbappend(&so->so_rcv, m);
563 sbappendrecord(&so->so_rcv, m);
565 cb->s_rhdr = *mtod(m, struct sphdr *);
568 m->m_pkthdr.len -= SPINC;
569 sbappend(&so->so_rcv, m);
574 if (wakeup) sorwakeup(so);
578 spp_ctlinput(cmd, arg)
583 extern u_char nsctlerrmap[];
584 extern spp_abort(), spp_quench();
585 extern struct nspcb *idp_drop();
586 struct ns_errp *errp;
588 struct sockaddr_ns *sns;
591 if (cmd < 0 || cmd > PRC_NCMDS)
593 type = NS_ERR_UNREACH_HOST;
602 case PRC_HOSTUNREACH:
603 sns = (struct sockaddr_ns *)arg;
604 if (sns->sns_family != AF_NS)
610 errp = (struct ns_errp *)arg;
611 na = &errp->ns_err_idp.idp_dna;
612 type = errp->ns_err_num;
613 type = ntohs((u_short)type);
617 case NS_ERR_UNREACH_HOST:
618 ns_pcbnotify(na, (int)nsctlerrmap[cmd], spp_abort, (long) 0);
623 nsp = ns_pcblookup(na, errp->ns_err_idp.idp_sna.x_port,
627 (void) spp_drop((struct sppcb *)nsp->nsp_pcb,
628 (int)nsctlerrmap[cmd]);
630 (void) idp_drop(nsp, (int)nsctlerrmap[cmd]);
635 ns_pcbnotify(na, 0, spp_quench, (long) 0);
639 * When a source quench is received, close congestion window
640 * to one packet. We will gradually open it again as we proceed.
645 struct sppcb *cb = nstosppcb(nsp);
654 register struct nspcb *nsp;
656 register struct sppcb *cb = (struct sppcb *)(nsp->nsp_pcb);
657 register struct mbuf *m;
658 register struct spidp *si;
662 struct mbuf *firstbad, *m0;
666 * The notification that we have sent
667 * too much is bad news -- we will
668 * have to go through queued up so far
669 * splitting ones which are too big and
670 * reassigning sequence numbers and checksums.
671 * we should then retransmit all packets from
672 * one above the offending packet to the last one
673 * we had sent (or our allocation)
674 * then the offending one so that the any queued
675 * data at our destination will be discarded.
677 ep = (struct ns_errp *)nsp->nsp_notify_param;
678 sb = &nsp->nsp_socket->so_snd;
679 cb->s_mtu = ep->ns_err_param;
680 badseq = SI(&ep->ns_err_idp)->si_seq;
681 for (m = sb->sb_mb; m; m = m->m_act) {
682 si = mtod(m, struct spidp *);
683 if (si->si_seq == badseq)
689 /* calculate length */
690 for (m0 = m, len = 0; m ; m = m->m_next)
692 if (len > cb->s_mtu) {
701 register struct sppcb *cb;
704 struct socket *so = cb->s_nspcb->nsp_socket;
705 register struct mbuf *m;
706 register struct spidp *si = (struct spidp *) 0;
707 register struct sockbuf *sb = &so->so_snd;
708 int len = 0, win, rcv_win;
709 short span, off, recordp = 0;
711 int error = 0, sendalot;
722 * Make sure that packet isn't too big.
724 for (m = m0; m ; m = m->m_next) {
727 if (m->m_flags & M_EOR)
730 datalen = (cb->s_flags & SF_HO) ?
731 len - sizeof (struct sphdr) : len;
733 if (cb->s_flags & SF_PI) {
737 int oldEM = cb->s_cc & SP_EM;
742 * Here we are only being called
743 * from usrreq(), so it is OK to
746 m = m_copym(m0, 0, mtu, M_WAIT);
747 if (cb->s_flags & SF_NEWCALL) {
751 mm->m_flags &= ~M_EOR;
755 error = spp_output(cb, m);
768 * Force length even, by adding a "garbage byte" if
773 if (M_TRAILINGSPACE(m) >= 1)
776 struct mbuf *m1 = m_get(M_DONTWAIT, MT_DATA);
783 *(mtod(m1, u_char *)) = 0;
787 m = m_gethdr(M_DONTWAIT, MT_HEADER);
793 * Fill in mbuf with extended SP header
794 * and addresses and length put into network format.
796 MH_ALIGN(m, sizeof (struct spidp));
797 m->m_len = sizeof (struct spidp);
799 si = mtod(m, struct spidp *);
800 si->si_i = *cb->s_idp;
801 si->si_s = cb->s_shdr;
802 if ((cb->s_flags & SF_PI) && (cb->s_flags & SF_HO)) {
803 register struct sphdr *sh;
804 if (m0->m_len < sizeof (*sh)) {
805 if((m0 = m_pullup(m0, sizeof(*sh))) == NULL) {
812 sh = mtod(m0, struct sphdr *);
813 si->si_dt = sh->sp_dt;
814 si->si_cc |= sh->sp_cc & SP_EM;
815 m0->m_len -= sizeof (*sh);
816 m0->m_data += sizeof (*sh);
820 if ((cb->s_flags2 & SF_NEWCALL) && recordp) {
824 if (cb->s_oobflags & SF_SOOB) {
827 * make sure OB packets convey exactly 1 byte.
828 * If the packet is 1 byte or larger, we
829 * have already guaranted there to be at least
830 * one garbage byte for the checksum, and
831 * extra bytes shouldn't hurt!
833 if (len > sizeof(*si)) {
835 len = (1 + sizeof(*si));
838 si->si_len = htons((u_short)len);
839 m->m_pkthdr.len = ((len - 1) | 1) + 1;
841 * queue stuff up for output
843 sbappendrecord(sb, m);
847 idle = (cb->s_smax == (cb->s_rack - 1));
851 off = cb->s_snxt - cb->s_rack;
852 win = min(cb->s_swnd, (cb->s_cwnd/CUNIT));
855 * If in persist timeout with window of 0, send a probe.
856 * Otherwise, if window is small but nonzero
857 * and timer expired, send what we can and go into
860 if (cb->s_force == 1 + SPPT_PERSIST) {
862 cb->s_timer[SPPT_PERSIST] = 0;
866 span = cb->s_seq - cb->s_rack;
867 len = min(span, win) - off;
871 * Window shrank after we went into it.
872 * If window shrank to 0, cancel pending
873 * restransmission and pull s_snxt back
874 * to (closed) window. We will enter persist
875 * state below. If the widndow didn't close completely,
876 * just wait for an ACK.
880 cb->s_timer[SPPT_REXMT] = 0;
881 cb->s_snxt = cb->s_rack;
886 rcv_win = sbspace(&so->so_rcv);
889 * Send if we owe peer an ACK.
891 if (cb->s_oobflags & SF_SOOB) {
893 * must transmit this out of band packet
895 cb->s_oobflags &= ~ SF_SOOB;
897 sppstat.spps_sndurg++;
900 if (cb->s_flags & SF_ACKNOW)
902 if (cb->s_state < TCPS_ESTABLISHED)
905 * Silly window can't happen in spp.
906 * Code from tcp deleted.
911 * Compare available window to amount of window
912 * known to peer (as advertised window less
913 * next expected input.) If the difference is at least two
914 * packets or at least 35% of the mximum possible window,
915 * then want to send a window update to peer.
918 u_short delta = 1 + cb->s_alo - cb->s_ack;
919 int adv = rcv_win - (delta * cb->s_mtu);
921 if ((so->so_rcv.sb_cc == 0 && adv >= (2 * cb->s_mtu)) ||
922 (100 * adv / so->so_rcv.sb_hiwat >= 35)) {
923 sppstat.spps_sndwinup++;
924 cb->s_flags |= SF_ACKNOW;
930 * Many comments from tcp_output.c are appropriate here
932 * If send window is too small, there is data to transmit, and no
933 * retransmit or persist is pending, then go to persist state.
934 * If nothing happens soon, send when timer expires:
935 * if window is nonzero, transmit what we can,
936 * otherwise send a probe.
938 if (so->so_snd.sb_cc && cb->s_timer[SPPT_REXMT] == 0 &&
939 cb->s_timer[SPPT_PERSIST] == 0) {
944 * No reason to send a packet, just return.
951 * Find requested packet.
955 cb->s_want = cb->s_snxt;
956 for (m = sb->sb_mb; m; m = m->m_act) {
957 si = mtod(m, struct spidp *);
958 if (SSEQ_LEQ(cb->s_snxt, si->si_seq))
963 if (si->si_seq == cb->s_snxt)
966 sppstat.spps_sndvoid++, si = 0;
974 alo = cb->s_ack - 1 + (rcv_win / ((short)cb->s_mtu));
975 if (SSEQ_LT(alo, cb->s_alo))
980 * must make a copy of this packet for
981 * idp_output to monkey with
983 m = m_copy(dtom(si), 0, (int)M_COPYALL);
987 si = mtod(m, struct spidp *);
988 if (SSEQ_LT(si->si_seq, cb->s_smax))
989 sppstat.spps_sndrexmitpack++;
991 sppstat.spps_sndpack++;
992 } else if (cb->s_force || cb->s_flags & SF_ACKNOW) {
994 * Must send an acknowledgement or a probe
997 sppstat.spps_sndprobe++;
998 if (cb->s_flags & SF_ACKNOW)
999 sppstat.spps_sndacks++;
1000 m = m_gethdr(M_DONTWAIT, MT_HEADER);
1004 * Fill in mbuf with extended SP header
1005 * and addresses and length put into network format.
1007 MH_ALIGN(m, sizeof (struct spidp));
1008 m->m_len = sizeof (*si);
1009 m->m_pkthdr.len = sizeof (*si);
1010 si = mtod(m, struct spidp *);
1011 si->si_i = *cb->s_idp;
1012 si->si_s = cb->s_shdr;
1013 si->si_seq = cb->s_smax + 1;
1014 si->si_len = htons(sizeof (*si));
1018 if (so->so_options & SO_DEBUG || traceallspps)
1019 spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
1023 * Stuff checksum and output datagram.
1025 if ((si->si_cc & SP_SP) == 0) {
1026 if (cb->s_force != (1 + SPPT_PERSIST) ||
1027 cb->s_timer[SPPT_PERSIST] == 0) {
1029 * If this is a new packet and we are not currently
1030 * timing anything, time this one.
1032 if (SSEQ_LT(cb->s_smax, si->si_seq)) {
1033 cb->s_smax = si->si_seq;
1034 if (cb->s_rtt == 0) {
1035 sppstat.spps_segstimed++;
1036 cb->s_rtseq = si->si_seq;
1041 * Set rexmt timer if not currently set,
1042 * Initial value for retransmit timer is smoothed
1043 * round-trip time + 2 * round-trip time variance.
1044 * Initialize shift counter which is used for backoff
1045 * of retransmit time.
1047 if (cb->s_timer[SPPT_REXMT] == 0 &&
1048 cb->s_snxt != cb->s_rack) {
1049 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1050 if (cb->s_timer[SPPT_PERSIST]) {
1051 cb->s_timer[SPPT_PERSIST] = 0;
1055 } else if (SSEQ_LT(cb->s_smax, si->si_seq)) {
1056 cb->s_smax = si->si_seq;
1058 } else if (cb->s_state < TCPS_ESTABLISHED) {
1060 cb->s_rtt = 1; /* Time initial handshake */
1061 if (cb->s_timer[SPPT_REXMT] == 0)
1062 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1066 * Do not request acks when we ack their data packets or
1067 * when we do a gratuitous window update.
1069 if (((si->si_cc & SP_SP) == 0) || cb->s_force)
1071 si->si_seq = htons(si->si_seq);
1072 si->si_alo = htons(alo);
1073 si->si_ack = htons(cb->s_ack);
1077 len = ntohs(si->si_len);
1080 si->si_sum = ns_cksum(m, len);
1082 si->si_sum = 0xffff;
1085 if (so->so_options & SO_DEBUG || traceallspps)
1086 spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
1088 if (so->so_options & SO_DONTROUTE)
1089 error = ns_output(m, (struct route *)0, NS_ROUTETOIF);
1091 error = ns_output(m, &cb->s_nspcb->nsp_route, 0);
1096 sppstat.spps_sndtotal++;
1098 * Data sent (as far as we can tell).
1099 * If this advertises a larger window than any other segment,
1100 * then remember the size of the advertized window.
1101 * Any pending ACK has now been sent.
1104 cb->s_flags &= ~(SF_ACKNOW|SF_DELACK);
1105 if (SSEQ_GT(alo, cb->s_alo))
1113 int spp_do_persist_panics = 0;
1116 register struct sppcb *cb;
1118 register t = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
1119 extern int spp_backoff[];
1121 if (cb->s_timer[SPPT_REXMT] && spp_do_persist_panics)
1122 panic("spp_output REXMT");
1124 * Start/restart persistance timer.
1126 SPPT_RANGESET(cb->s_timer[SPPT_PERSIST],
1127 t*spp_backoff[cb->s_rxtshift],
1128 SPPTV_PERSMIN, SPPTV_PERSMAX);
1129 if (cb->s_rxtshift < SPP_MAXRXTSHIFT)
1133 spp_ctloutput(req, so, level, name, value)
1137 struct mbuf **value;
1139 register struct mbuf *m;
1140 struct nspcb *nsp = sotonspcb(so);
1141 register struct sppcb *cb;
1142 int mask, error = 0;
1144 if (level != NSPROTO_SPP) {
1145 /* This will have to be changed when we do more general
1146 stacking of protocols */
1147 return (idp_ctloutput(req, so, level, name, value));
1153 cb = nstosppcb(nsp);
1160 m = m_get(M_DONTWAIT, MT_DATA);
1165 case SO_HEADERS_ON_INPUT:
1169 case SO_HEADERS_ON_OUTPUT:
1172 m->m_len = sizeof(short);
1173 *mtod(m, short *) = cb->s_flags & mask;
1177 m->m_len = sizeof(u_short);
1178 *mtod(m, short *) = cb->s_mtu;
1181 case SO_LAST_HEADER:
1182 m->m_len = sizeof(struct sphdr);
1183 *mtod(m, struct sphdr *) = cb->s_rhdr;
1186 case SO_DEFAULT_HEADERS:
1187 m->m_len = sizeof(struct spidp);
1188 *mtod(m, struct sphdr *) = cb->s_shdr;
1198 if (value == 0 || *value == 0) {
1205 case SO_HEADERS_ON_INPUT:
1209 case SO_HEADERS_ON_OUTPUT:
1212 if (cb->s_flags & SF_PI) {
1213 ok = mtod(*value, int *);
1215 cb->s_flags |= mask;
1217 cb->s_flags &= ~mask;
1218 } else error = EINVAL;
1222 cb->s_mtu = *(mtod(*value, u_short *));
1227 ok = mtod(*value, int *);
1229 cb->s_flags2 |= SF_NEWCALL;
1232 cb->s_flags2 &= ~SF_NEWCALL;
1238 case SO_DEFAULT_HEADERS:
1240 register struct sphdr *sp
1241 = mtod(*value, struct sphdr *);
1242 cb->s_dt = sp->sp_dt;
1243 cb->s_cc = sp->sp_cc & SP_EM;
1258 spp_usrreq(so, req, m, nam, controlp)
1261 struct mbuf *m, *nam, *controlp;
1263 struct nspcb *nsp = sotonspcb(so);
1264 register struct sppcb *cb;
1266 int error = 0, ostate;
1268 register struct sockbuf *sb;
1270 if (req == PRU_CONTROL)
1271 return (ns_control(so, (int)m, (caddr_t)nam,
1272 (struct ifnet *)controlp));
1274 if (req != PRU_ATTACH) {
1279 cb = nstosppcb(nsp);
1281 ostate = cb ? cb->s_state : 0;
1290 error = ns_pcballoc(so, &nspcb);
1293 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1294 error = soreserve(so, (u_long) 3072, (u_long) 3072);
1298 nsp = sotonspcb(so);
1300 mm = m_getclr(M_DONTWAIT, MT_PCB);
1307 cb = mtod(mm, struct sppcb *);
1308 mm = m_getclr(M_DONTWAIT, MT_HEADER);
1310 (void) m_free(dtom(m));
1314 cb->s_idp = mtod(mm, struct idp *);
1315 cb->s_state = TCPS_LISTEN;
1318 cb->s_q.si_next = cb->s_q.si_prev = &cb->s_q;
1320 cb->s_mtu = 576 - sizeof (struct spidp);
1321 cb->s_cwnd = sbspace(sb) * CUNIT / cb->s_mtu;
1322 cb->s_ssthresh = cb->s_cwnd;
1323 cb->s_cwmx = sbspace(sb) * CUNIT /
1324 (2 * sizeof (struct spidp));
1325 /* Above is recomputed when connecting to account
1326 for changed buffering or mtu's */
1327 cb->s_rtt = SPPTV_SRTTBASE;
1328 cb->s_rttvar = SPPTV_SRTTDFLT << 2;
1329 SPPT_RANGESET(cb->s_rxtcur,
1330 ((SPPTV_SRTTBASE >> 2) + (SPPTV_SRTTDFLT << 2)) >> 1,
1331 SPPTV_MIN, SPPTV_REXMTMAX);
1332 nsp->nsp_pcb = (caddr_t) cb;
1340 if (cb->s_state > TCPS_LISTEN)
1341 cb = spp_disconnect(cb);
1347 error = ns_pcbbind(nsp, nam);
1351 if (nsp->nsp_lport == 0)
1352 error = ns_pcbbind(nsp, (struct mbuf *)0);
1354 cb->s_state = TCPS_LISTEN;
1358 * Initiate connection to peer.
1359 * Enter SYN_SENT state, and mark socket as connecting.
1360 * Start keep-alive timer, setup prototype header,
1361 * Send initial system packet requesting connection.
1364 if (nsp->nsp_lport == 0) {
1365 error = ns_pcbbind(nsp, (struct mbuf *)0);
1369 error = ns_pcbconnect(nsp, nam);
1373 sppstat.spps_connattempt++;
1374 cb->s_state = TCPS_SYN_SENT;
1377 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
1378 cb->s_force = 1 + SPPTV_KEEP;
1380 * Other party is required to respond to
1381 * the port I send from, but he is not
1382 * required to answer from where I am sending to,
1383 * so allow wildcarding.
1384 * original port I am sending to is still saved in
1388 error = spp_output(cb, (struct mbuf *) 0);
1396 * We may decide later to implement connection closing
1397 * handshaking at the spp level optionally.
1398 * here is the hook to do it:
1400 case PRU_DISCONNECT:
1401 cb = spp_disconnect(cb);
1405 * Accept a connection. Essentially all the work is
1406 * done at higher levels; just return the address
1407 * of the peer, storing through addr.
1410 struct sockaddr_ns *sns = mtod(nam, struct sockaddr_ns *);
1412 nam->m_len = sizeof (struct sockaddr_ns);
1413 sns->sns_family = AF_NS;
1414 sns->sns_addr = nsp->nsp_faddr;
1420 cb = spp_usrclosed(cb);
1422 error = spp_output(cb, (struct mbuf *) 0);
1426 * After a receive, possibly send acknowledgment
1427 * updating allocation.
1430 cb->s_flags |= SF_RVD;
1431 (void) spp_output(cb, (struct mbuf *) 0);
1432 cb->s_flags &= ~SF_RVD;
1436 (void) spp_drop(cb, ECONNABORTED);
1446 if ((cb->s_oobflags & SF_IOOB) || so->so_oobmark ||
1447 (so->so_state & SS_RCVATMARK)) {
1449 *mtod(m, caddr_t) = cb->s_iobc;
1456 if (sbspace(&so->so_snd) < -512) {
1460 cb->s_oobflags |= SF_SOOB;
1464 u_short *p = mtod(controlp, u_short *);
1466 if ((p[0] == 5) && p[1] == 1) { /* XXXX, for testing */
1467 cb->s_shdr.sp_dt = *(u_char *)(&p[2]);
1473 error = spp_output(cb, m);
1478 ns_setsockaddr(nsp, nam);
1482 ns_setpeeraddr(nsp, nam);
1486 cb = spp_timers(cb, (int)nam);
1487 req |= ((int)nam) << 8;
1499 if (cb && (so->so_options & SO_DEBUG || traceallspps))
1500 spp_trace(SA_USER, (u_char)ostate, cb, (struct spidp *)0, req);
1502 if (controlp != NULL)
1510 spp_usrreq_sp(so, req, m, nam, controlp)
1513 struct mbuf *m, *nam, *controlp;
1515 int error = spp_usrreq(so, req, m, nam, controlp);
1517 if (req == PRU_ATTACH && error == 0) {
1518 struct nspcb *nsp = sotonspcb(so);
1519 ((struct sppcb *)nsp->nsp_pcb)->s_flags |=
1520 (SF_HI | SF_HO | SF_PI);
1526 * Create template to be used to send spp packets on a connection.
1527 * Called after host entry created, fills
1528 * in a skeletal spp header (choosing connection id),
1529 * minimizing the amount of work necessary when the connection is used.
1532 register struct sppcb *cb;
1534 register struct nspcb *nsp = cb->s_nspcb;
1535 register struct idp *idp = cb->s_idp;
1536 register struct sockbuf *sb = &(nsp->nsp_socket->so_snd);
1538 idp->idp_pt = NSPROTO_SPP;
1539 idp->idp_sna = nsp->nsp_laddr;
1540 idp->idp_dna = nsp->nsp_faddr;
1541 cb->s_sid = htons(spp_iss);
1542 spp_iss += SPP_ISSINCR/2;
1544 cb->s_cwnd = (sbspace(sb) * CUNIT) / cb->s_mtu;
1545 cb->s_ssthresh = cb->s_cwnd; /* Try to expand fast to full complement
1547 cb->s_cwmx = (sbspace(sb) * CUNIT) / (2 * sizeof(struct spidp));
1548 cb->s_cwmx = max(cb->s_cwmx, cb->s_cwnd);
1549 /* But allow for lots of little packets as well */
1553 * Close a SPIP control block:
1554 * discard spp control block itself
1555 * discard ns protocol control block
1556 * wake up any sleepers
1560 register struct sppcb *cb;
1562 register struct spidp_q *s;
1563 struct nspcb *nsp = cb->s_nspcb;
1564 struct socket *so = nsp->nsp_socket;
1565 register struct mbuf *m;
1567 s = cb->s_q.si_next;
1568 while (s != &(cb->s_q)) {
1570 m = dtom(s->si_prev);
1574 (void) m_free(dtom(cb->s_idp));
1575 (void) m_free(dtom(cb));
1577 soisdisconnected(so);
1579 sppstat.spps_closed++;
1580 return ((struct sppcb *)0);
1583 * Someday we may do level 3 handshaking
1584 * to close a connection or send a xerox style error.
1585 * For now, just close.
1589 register struct sppcb *cb;
1591 return (spp_close(cb));
1595 register struct sppcb *cb;
1597 return (spp_close(cb));
1600 * Drop connection, reporting
1601 * the specified error.
1605 register struct sppcb *cb;
1608 struct socket *so = cb->s_nspcb->nsp_socket;
1611 * someday, in the xerox world
1612 * we will generate error protocol packets
1613 * announcing that the socket has gone away.
1615 if (TCPS_HAVERCVDSYN(cb->s_state)) {
1616 sppstat.spps_drops++;
1617 cb->s_state = TCPS_CLOSED;
1618 /*(void) tcp_output(cb);*/
1620 sppstat.spps_conndrops++;
1621 so->so_error = errno;
1622 return (spp_close(cb));
1629 (void) spp_close((struct sppcb *)nsp->nsp_pcb);
1632 int spp_backoff[SPP_MAXRXTSHIFT+1] =
1633 { 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 };
1635 * Fast timeout routine for processing delayed acks
1639 register struct nspcb *nsp;
1640 register struct sppcb *cb;
1643 nsp = nspcb.nsp_next;
1645 for (; nsp != &nspcb; nsp = nsp->nsp_next)
1646 if ((cb = (struct sppcb *)nsp->nsp_pcb) &&
1647 (cb->s_flags & SF_DELACK)) {
1648 cb->s_flags &= ~SF_DELACK;
1649 cb->s_flags |= SF_ACKNOW;
1650 sppstat.spps_delack++;
1651 (void) spp_output(cb, (struct mbuf *) 0);
1657 * spp protocol timeout routine called every 500 ms.
1658 * Updates the timers in all active pcb's and
1659 * causes finite state machine actions if timers expire.
1663 register struct nspcb *ip, *ipnxt;
1664 register struct sppcb *cb;
1669 * Search through tcb's and update active timers.
1671 ip = nspcb.nsp_next;
1676 while (ip != &nspcb) {
1678 ipnxt = ip->nsp_next;
1681 for (i = 0; i < SPPT_NTIMERS; i++) {
1682 if (cb->s_timer[i] && --cb->s_timer[i] == 0) {
1683 (void) spp_usrreq(cb->s_nspcb->nsp_socket,
1684 PRU_SLOWTIMO, (struct mbuf *)0,
1685 (struct mbuf *)i, (struct mbuf *)0,
1687 if (ipnxt->nsp_prev != ip)
1697 spp_iss += SPP_ISSINCR/PR_SLOWHZ; /* increment iss */
1701 * SPP timer processing.
1704 spp_timers(cb, timer)
1705 register struct sppcb *cb;
1711 cb->s_force = 1 + timer;
1715 * 2 MSL timeout in shutdown went off. TCP deletes connection
1719 printf("spp: SPPT_2MSL went off for no reason\n");
1720 cb->s_timer[timer] = 0;
1724 * Retransmission timer went off. Message has not
1725 * been acked within retransmit interval. Back off
1726 * to a longer retransmit interval and retransmit one packet.
1729 if (++cb->s_rxtshift > SPP_MAXRXTSHIFT) {
1730 cb->s_rxtshift = SPP_MAXRXTSHIFT;
1731 sppstat.spps_timeoutdrop++;
1732 cb = spp_drop(cb, ETIMEDOUT);
1735 sppstat.spps_rexmttimeo++;
1736 rexmt = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
1737 rexmt *= spp_backoff[cb->s_rxtshift];
1738 SPPT_RANGESET(cb->s_rxtcur, rexmt, SPPTV_MIN, SPPTV_REXMTMAX);
1739 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1741 * If we have backed off fairly far, our srtt
1742 * estimate is probably bogus. Clobber it
1743 * so we'll take the next rtt measurement as our srtt;
1744 * move the current srtt into rttvar to keep the current
1745 * retransmit times until then.
1747 if (cb->s_rxtshift > SPP_MAXRXTSHIFT / 4 ) {
1748 cb->s_rttvar += (cb->s_srtt >> 2);
1751 cb->s_snxt = cb->s_rack;
1753 * If timing a packet, stop the timer.
1757 * See very long discussion in tcp_timer.c about congestion
1758 * window and sstrhesh
1760 win = min(cb->s_swnd, (cb->s_cwnd/CUNIT)) / 2;
1764 cb->s_ssthresh = win * CUNIT;
1765 (void) spp_output(cb, (struct mbuf *) 0);
1769 * Persistance timer into zero window.
1770 * Force a probe to be sent.
1773 sppstat.spps_persisttimeo++;
1775 (void) spp_output(cb, (struct mbuf *) 0);
1779 * Keep-alive timer went off; send something
1780 * or drop connection if idle for too long.
1783 sppstat.spps_keeptimeo++;
1784 if (cb->s_state < TCPS_ESTABLISHED)
1786 if (cb->s_nspcb->nsp_socket->so_options & SO_KEEPALIVE) {
1787 if (cb->s_idle >= SPPTV_MAXIDLE)
1789 sppstat.spps_keepprobe++;
1790 (void) spp_output(cb, (struct mbuf *) 0);
1793 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
1796 sppstat.spps_keepdrops++;
1797 cb = spp_drop(cb, ETIMEDOUT);
1803 int SppcbSize = sizeof (struct sppcb);
1804 int NspcbSize = sizeof (struct nspcb);