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
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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
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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.
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23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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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 $
35 * $DragonFly: src/sys/netproto/ns/spp_usrreq.c,v 1.9 2004/06/02 14:43:03 eirikn Exp $
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
42 #include <sys/protosw.h>
43 #include <sys/socket.h>
44 #include <sys/socketvar.h>
45 #include <sys/errno.h>
48 #include <net/route.h>
49 #include <netinet/tcp_fsm.h>
58 #include "spp_timer.h"
60 #include "spp_debug.h"
62 extern u_char nsctlerrmap[]; /* from ns_input.c */
63 extern int idpcksum; /* from ns_input.c */
65 struct spp_istat spp_istat;
67 int spp_backoff[SPP_MAXRXTSHIFT+1] =
68 { 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 };
71 * SP protocol implementation.
77 spp_iss = 1; /* WRONG !! should fish it out of TODR */
79 struct spidp spp_savesi;
81 extern int sppconsdebug;
83 int spp_use_delack = 0;
84 u_short spp_newchecks[50];
93 struct spidp *si = mtod(m, struct spidp *);
99 sppstat.spps_rcvtotal++;
101 panic("No nspcb in spp_input");
106 if (cb == 0) goto bad;
108 if (m->m_len < sizeof(*si)) {
109 if ((m = m_pullup(m, sizeof(*si))) == 0) {
110 sppstat.spps_rcvshort++;
113 si = mtod(m, struct spidp *);
115 si->si_seq = ntohs(si->si_seq);
116 si->si_ack = ntohs(si->si_ack);
117 si->si_alo = ntohs(si->si_alo);
119 so = nsp->nsp_socket;
120 if (so->so_options & SO_DEBUG || traceallspps) {
121 ostate = cb->s_state;
124 if (so->so_options & SO_ACCEPTCONN) {
125 struct sppcb *ocb = cb;
127 so = sonewconn(so, 0);
132 * This is ugly, but ....
134 * Mark socket as temporary until we're
135 * committed to keeping it. The code at
136 * ``drop'' and ``dropwithreset'' check the
137 * flag dropsocket to see if the temporary
138 * socket created here should be discarded.
139 * We mark the socket as discardable until
140 * we're committed to it below in TCPS_LISTEN.
143 nsp = (struct nspcb *)so->so_pcb;
144 nsp->nsp_laddr = si->si_dna;
146 cb->s_mtu = ocb->s_mtu; /* preserve sockopts */
147 cb->s_flags = ocb->s_flags; /* preserve sockopts */
148 cb->s_flags2 = ocb->s_flags2; /* preserve sockopts */
149 cb->s_state = TCPS_LISTEN;
153 * Packet received on connection.
154 * reset idle time and keep-alive timer;
157 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
159 switch (cb->s_state) {
163 struct sockaddr_ns *sns;
164 struct ns_addr laddr;
167 * If somebody here was carying on a conversation
168 * and went away, and his pen pal thinks he can
169 * still talk, we get the misdirected packet.
171 if (spp_hardnosed && (si->si_did != 0 || si->si_seq != 0)) {
175 am = m_get(MB_DONTWAIT, MT_SONAME);
178 am->m_len = sizeof (struct sockaddr_ns);
179 sns = mtod(am, struct sockaddr_ns *);
180 sns->sns_len = sizeof(*sns);
181 sns->sns_family = AF_NS;
182 sns->sns_addr = si->si_sna;
183 laddr = nsp->nsp_laddr;
184 if (ns_nullhost(laddr))
185 nsp->nsp_laddr = si->si_dna;
186 if (ns_pcbconnect(nsp, am)) {
187 nsp->nsp_laddr = laddr;
194 dropsocket = 0; /* committed to socket */
195 cb->s_did = si->si_sid;
196 cb->s_rack = si->si_ack;
197 cb->s_ralo = si->si_alo;
198 #define THREEWAYSHAKE
200 cb->s_state = TCPS_SYN_RECEIVED;
201 cb->s_force = 1 + SPPT_KEEP;
202 sppstat.spps_accepts++;
203 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
207 * This state means that we have heard a response
208 * to our acceptance of their connection
209 * It is probably logically unnecessary in this
212 case TCPS_SYN_RECEIVED: {
213 if (si->si_did!=cb->s_sid) {
218 nsp->nsp_fport = si->si_sport;
219 cb->s_timer[SPPT_REXMT] = 0;
220 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
222 cb->s_state = TCPS_ESTABLISHED;
223 sppstat.spps_accepts++;
228 * This state means that we have gotten a response
229 * to our attempt to establish a connection.
230 * We fill in the data from the other side,
231 * telling us which port to respond to, instead of the well-
232 * known one we might have sent to in the first place.
233 * We also require that this is a response to our
237 if (si->si_did!=cb->s_sid) {
241 sppstat.spps_connects++;
242 cb->s_did = si->si_sid;
243 cb->s_rack = si->si_ack;
244 cb->s_ralo = si->si_alo;
245 cb->s_dport = nsp->nsp_fport = si->si_sport;
246 cb->s_timer[SPPT_REXMT] = 0;
247 cb->s_flags |= SF_ACKNOW;
249 cb->s_state = TCPS_ESTABLISHED;
250 /* Use roundtrip time of connection request for initial rtt */
252 cb->s_srtt = cb->s_rtt << 3;
253 cb->s_rttvar = cb->s_rtt << 1;
254 SPPT_RANGESET(cb->s_rxtcur,
255 ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
256 SPPTV_MIN, SPPTV_REXMTMAX);
260 if (so->so_options & SO_DEBUG || traceallspps)
261 spp_trace(SA_INPUT, (u_char)ostate, cb, &spp_savesi, 0);
263 m->m_len -= sizeof (struct idp);
264 m->m_pkthdr.len -= sizeof (struct idp);
265 m->m_data += sizeof (struct idp);
267 if (spp_reass(cb, si)) {
270 if (cb->s_force || (cb->s_flags & (SF_ACKNOW|SF_WIN|SF_RXT)))
271 (void) spp_output(cb, (struct mbuf *)0);
272 cb->s_flags &= ~(SF_WIN|SF_RXT);
278 si->si_seq = ntohs(si->si_seq);
279 si->si_ack = ntohs(si->si_ack);
280 si->si_alo = ntohs(si->si_alo);
281 ns_error(dtom(si), NS_ERR_NOSOCK, 0);
282 if (cb->s_nspcb->nsp_socket->so_options & SO_DEBUG || traceallspps)
283 spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);
288 if (cb == 0 || cb->s_nspcb->nsp_socket->so_options & SO_DEBUG ||
290 spp_trace(SA_DROP, (u_char)ostate, cb, &spp_savesi, 0);
294 int spprexmtthresh = 3;
297 * This is structurally similar to the tcp reassembly routine
298 * but its function is somewhat different: It merely queues
299 * packets up, and suppresses duplicates.
308 struct socket *so = cb->s_nspcb->nsp_socket;
309 char packetp = cb->s_flags & SF_HI;
316 * Update our news from them.
318 if (si->si_cc & SP_SA)
319 cb->s_flags |= (spp_use_delack ? SF_DELACK : SF_ACKNOW);
320 if (SSEQ_GT(si->si_alo, cb->s_ralo))
321 cb->s_flags |= SF_WIN;
322 if (SSEQ_LEQ(si->si_ack, cb->s_rack)) {
323 if ((si->si_cc & SP_SP) && cb->s_rack != (cb->s_smax + 1)) {
324 sppstat.spps_rcvdupack++;
326 * If this is a completely duplicate ack
327 * and other conditions hold, we assume
328 * a packet has been dropped and retransmit
329 * it exactly as in tcp_input().
331 if (si->si_ack != cb->s_rack ||
332 si->si_alo != cb->s_ralo)
334 else if (++cb->s_dupacks == spprexmtthresh) {
335 u_short onxt = cb->s_snxt;
336 int cwnd = cb->s_cwnd;
338 cb->s_snxt = si->si_ack;
340 cb->s_force = 1 + SPPT_REXMT;
341 (void) spp_output(cb, (struct mbuf *)0);
342 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
344 if (cwnd >= 4 * CUNIT)
345 cb->s_cwnd = cwnd / 2;
346 if (SSEQ_GT(onxt, cb->s_snxt))
356 * If our correspondent acknowledges data we haven't sent
357 * TCP would drop the packet after acking. We'll be a little
360 if (SSEQ_GT(si->si_ack, (cb->s_smax + 1))) {
361 sppstat.spps_rcvacktoomuch++;
362 si->si_ack = cb->s_smax + 1;
364 sppstat.spps_rcvackpack++;
366 * If transmit timer is running and timed sequence
367 * number was acked, update smoothed round trip time.
368 * See discussion of algorithm in tcp_input.c
370 if (cb->s_rtt && SSEQ_GT(si->si_ack, cb->s_rtseq)) {
371 sppstat.spps_rttupdated++;
372 if (cb->s_srtt != 0) {
374 delta = cb->s_rtt - (cb->s_srtt >> 3);
375 if ((cb->s_srtt += delta) <= 0)
379 delta -= (cb->s_rttvar >> 2);
380 if ((cb->s_rttvar += delta) <= 0)
384 * No rtt measurement yet
386 cb->s_srtt = cb->s_rtt << 3;
387 cb->s_rttvar = cb->s_rtt << 1;
391 SPPT_RANGESET(cb->s_rxtcur,
392 ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
393 SPPTV_MIN, SPPTV_REXMTMAX);
396 * If all outstanding data is acked, stop retransmit
397 * timer and remember to restart (more output or persist).
398 * If there is more data to be acked, restart retransmit
399 * timer, using current (possibly backed-off) value;
401 if (si->si_ack == cb->s_smax + 1) {
402 cb->s_timer[SPPT_REXMT] = 0;
403 cb->s_flags |= SF_RXT;
404 } else if (cb->s_timer[SPPT_PERSIST] == 0)
405 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
407 * When new data is acked, open the congestion window.
408 * If the window gives us less than ssthresh packets
409 * in flight, open exponentially (maxseg at a time).
410 * Otherwise open linearly (maxseg^2 / cwnd at a time).
413 if (cb->s_cwnd > cb->s_ssthresh)
414 incr = max(incr * incr / cb->s_cwnd, 1);
415 cb->s_cwnd = min(cb->s_cwnd + incr, cb->s_cwmx);
417 * Trim Acked data from output queue.
419 while ((m = so->so_snd.sb_mb) != NULL) {
420 if (SSEQ_LT((mtod(m, struct spidp *))->si_seq, si->si_ack))
421 sbdroprecord(&so->so_snd);
426 cb->s_rack = si->si_ack;
428 if (SSEQ_LT(cb->s_snxt, cb->s_rack))
429 cb->s_snxt = cb->s_rack;
430 if (SSEQ_LT(cb->s_swl1, si->si_seq) || (cb->s_swl1 == si->si_seq &&
431 (SSEQ_LT(cb->s_swl2, si->si_ack) ||
432 (cb->s_swl2 == si->si_ack && SSEQ_LT(cb->s_ralo, si->si_alo))))) {
433 /* keep track of pure window updates */
434 if ((si->si_cc & SP_SP) && cb->s_swl2 == si->si_ack
435 && SSEQ_LT(cb->s_ralo, si->si_alo)) {
436 sppstat.spps_rcvwinupd++;
437 sppstat.spps_rcvdupack--;
439 cb->s_ralo = si->si_alo;
440 cb->s_swl1 = si->si_seq;
441 cb->s_swl2 = si->si_ack;
442 cb->s_swnd = (1 + si->si_alo - si->si_ack);
443 if (cb->s_swnd > cb->s_smxw)
444 cb->s_smxw = cb->s_swnd;
445 cb->s_flags |= SF_WIN;
448 * If this packet number is higher than that which
449 * we have allocated refuse it, unless urgent
451 if (SSEQ_GT(si->si_seq, cb->s_alo)) {
452 if (si->si_cc & SP_SP) {
453 sppstat.spps_rcvwinprobe++;
456 sppstat.spps_rcvpackafterwin++;
457 if (si->si_cc & SP_OB) {
458 if (SSEQ_GT(si->si_seq, cb->s_alo + 60)) {
459 ns_error(dtom(si), NS_ERR_FULLUP, 0);
461 } /* else queue this packet; */
463 /*register struct socket *so = cb->s_nspcb->nsp_socket;
464 if (so->so_state && SS_NOFDREF) {
465 ns_error(dtom(si), NS_ERR_NOSOCK, 0);
470 ns_error(dtom(si), NS_ERR_FULLUP, 0);
475 * If this is a system packet, we don't need to
476 * queue it up, and won't update acknowledge #
478 if (si->si_cc & SP_SP) {
482 * We have already seen this packet, so drop.
484 if (SSEQ_LT(si->si_seq, cb->s_ack)) {
486 sppstat.spps_rcvduppack++;
487 if (si->si_seq == cb->s_ack - 1)
492 * Loop through all packets queued up to insert in
493 * appropriate sequence.
495 for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
496 if (si->si_seq == SI(q)->si_seq) {
497 sppstat.spps_rcvduppack++;
500 if (SSEQ_LT(si->si_seq, SI(q)->si_seq)) {
501 sppstat.spps_rcvoopack++;
505 insque(si, q->si_prev);
507 * If this packet is urgent, inform process
509 if (si->si_cc & SP_OB) {
510 cb->s_iobc = ((char *)si)[1 + sizeof(*si)];
512 cb->s_oobflags |= SF_IOOB;
515 #define SPINC sizeof(struct sphdr)
517 * Loop through all packets queued up to update acknowledge
518 * number, and present all acknowledged data to user;
519 * If in packet interface mode, show packet headers.
521 for (q = cb->s_q.si_next; q!=&cb->s_q; q = q->si_next) {
522 if (SI(q)->si_seq == cb->s_ack) {
525 if (SI(q)->si_cc & SP_OB) {
526 cb->s_oobflags &= ~SF_IOOB;
527 if (so->so_rcv.sb_cc)
528 so->so_oobmark = so->so_rcv.sb_cc;
530 so->so_state |= SS_RCVATMARK;
535 sppstat.spps_rcvpack++;
537 if (cb->s_flags2 & SF_NEWCALL) {
538 struct sphdr *sp = mtod(m, struct sphdr *);
539 u_char dt = sp->sp_dt;
541 if (dt != cb->s_rhdr.sp_dt) {
543 m_getclr(MB_DONTWAIT, MT_CONTROL);
548 cb->s_rhdr.sp_dt = dt;
549 mm->m_len = 5; /*XXX*/
552 *(u_char *)(&s[2]) = dt;
553 sbappend(&so->so_rcv, mm);
556 if (sp->sp_cc & SP_OB) {
557 MCHTYPE(m, MT_OOBDATA);
560 so->so_state &= ~SS_RCVATMARK;
565 m->m_pkthdr.len -= SPINC;
567 if ((sp->sp_cc & SP_EM) || packetp) {
568 sbappendrecord(&so->so_rcv, m);
571 sbappend(&so->so_rcv, m);
575 sbappendrecord(&so->so_rcv, m);
577 cb->s_rhdr = *mtod(m, struct sphdr *);
580 m->m_pkthdr.len -= SPINC;
581 sbappend(&so->so_rcv, m);
586 if (wakeup) sorwakeup(so);
591 spp_ctlinput(cmd, arg)
596 struct ns_errp *errp = 0;
598 struct sockaddr_ns *sns;
601 if (cmd < 0 || cmd > PRC_NCMDS)
603 type = NS_ERR_UNREACH_HOST;
612 case PRC_HOSTUNREACH:
613 sns = (struct sockaddr_ns *)arg;
614 if (sns->sns_family != AF_NS)
620 errp = (struct ns_errp *)arg;
621 na = &errp->ns_err_idp.idp_dna;
622 type = errp->ns_err_num;
623 type = ntohs((u_short)type);
627 case NS_ERR_UNREACH_HOST:
628 ns_pcbnotify(na, (int)nsctlerrmap[cmd], spp_abort, (long) 0);
633 nsp = ns_pcblookup(na, errp->ns_err_idp.idp_sna.x_port,
637 (void) spp_drop((struct sppcb *)nsp->nsp_pcb,
638 (int)nsctlerrmap[cmd]);
640 (void) idp_drop(nsp, (int)nsctlerrmap[cmd]);
645 ns_pcbnotify(na, 0, spp_quench, (long) 0);
649 * When a source quench is received, close congestion window
650 * to one packet. We will gradually open it again as we proceed.
656 struct sppcb *cb = nstosppcb(nsp);
667 struct sppcb *cb = (struct sppcb *)(nsp->nsp_pcb);
673 struct mbuf *firstbad, *m0;
677 * The notification that we have sent
678 * too much is bad news -- we will
679 * have to go through queued up so far
680 * splitting ones which are too big and
681 * reassigning sequence numbers and checksums.
682 * we should then retransmit all packets from
683 * one above the offending packet to the last one
684 * we had sent (or our allocation)
685 * then the offending one so that the any queued
686 * data at our destination will be discarded.
688 ep = (struct ns_errp *)nsp->nsp_notify_param;
689 sb = &nsp->nsp_socket->so_snd;
690 cb->s_mtu = ep->ns_err_param;
691 badseq = SI(&ep->ns_err_idp)->si_seq;
692 for (m = sb->sb_mb; m; m = m->m_act) {
693 si = mtod(m, struct spidp *);
694 if (si->si_seq == badseq)
700 /* calculate length */
701 for (m0 = m, len = 0; m ; m = m->m_next)
703 if (len > cb->s_mtu) {
716 struct socket *so = cb->s_nspcb->nsp_socket;
718 struct spidp *si = (struct spidp *) 0;
719 struct sockbuf *sb = &so->so_snd;
720 int len = 0, win, rcv_win;
721 short span, off, recordp = 0;
723 int error = 0, sendalot;
733 * Make sure that packet isn't too big.
735 for (m = m0; m ; m = m->m_next) {
738 if (m->m_flags & M_EOR)
741 datalen = (cb->s_flags & SF_HO) ?
742 len - sizeof (struct sphdr) : len;
744 if (cb->s_flags & SF_PI) {
748 int oldEM = cb->s_cc & SP_EM;
753 * Here we are only being called
754 * from usrreq(), so it is OK to
757 m = m_copym(m0, 0, mtu, MB_WAIT);
758 if (cb->s_flags & SF_NEWCALL) {
762 mm->m_flags &= ~M_EOR;
766 error = spp_output(cb, m);
779 * Force length even, by adding a "garbage byte" if
784 if (M_TRAILINGSPACE(m) >= 1)
787 struct mbuf *m1 = m_get(MB_DONTWAIT, MT_DATA);
794 *(mtod(m1, u_char *)) = 0;
798 m = m_gethdr(MB_DONTWAIT, MT_HEADER);
804 * Fill in mbuf with extended SP header
805 * and addresses and length put into network format.
807 MH_ALIGN(m, sizeof (struct spidp));
808 m->m_len = sizeof (struct spidp);
810 si = mtod(m, struct spidp *);
811 si->si_i = *cb->s_idp;
812 si->si_s = cb->s_shdr;
813 if ((cb->s_flags & SF_PI) && (cb->s_flags & SF_HO)) {
815 if (m0->m_len < sizeof (*sh)) {
816 if((m0 = m_pullup(m0, sizeof(*sh))) == NULL) {
823 sh = mtod(m0, struct sphdr *);
824 si->si_dt = sh->sp_dt;
825 si->si_cc |= sh->sp_cc & SP_EM;
826 m0->m_len -= sizeof (*sh);
827 m0->m_data += sizeof (*sh);
831 if ((cb->s_flags2 & SF_NEWCALL) && recordp) {
835 if (cb->s_oobflags & SF_SOOB) {
838 * make sure OB packets convey exactly 1 byte.
839 * If the packet is 1 byte or larger, we
840 * have already guaranted there to be at least
841 * one garbage byte for the checksum, and
842 * extra bytes shouldn't hurt!
844 if (len > sizeof(*si)) {
846 len = (1 + sizeof(*si));
849 si->si_len = htons((u_short)len);
850 m->m_pkthdr.len = ((len - 1) | 1) + 1;
852 * queue stuff up for output
854 sbappendrecord(sb, m);
858 idle = (cb->s_smax == (cb->s_rack - 1));
862 off = cb->s_snxt - cb->s_rack;
863 win = min(cb->s_swnd, (cb->s_cwnd/CUNIT));
866 * If in persist timeout with window of 0, send a probe.
867 * Otherwise, if window is small but nonzero
868 * and timer expired, send what we can and go into
871 if (cb->s_force == 1 + SPPT_PERSIST) {
873 cb->s_timer[SPPT_PERSIST] = 0;
877 span = cb->s_seq - cb->s_rack;
878 len = min(span, win) - off;
882 * Window shrank after we went into it.
883 * If window shrank to 0, cancel pending
884 * restransmission and pull s_snxt back
885 * to (closed) window. We will enter persist
886 * state below. If the widndow didn't close completely,
887 * just wait for an ACK.
891 cb->s_timer[SPPT_REXMT] = 0;
892 cb->s_snxt = cb->s_rack;
897 rcv_win = sbspace(&so->so_rcv);
900 * Send if we owe peer an ACK.
902 if (cb->s_oobflags & SF_SOOB) {
904 * must transmit this out of band packet
906 cb->s_oobflags &= ~ SF_SOOB;
908 sppstat.spps_sndurg++;
911 if (cb->s_flags & SF_ACKNOW)
913 if (cb->s_state < TCPS_ESTABLISHED)
916 * Silly window can't happen in spp.
917 * Code from tcp deleted.
922 * Compare available window to amount of window
923 * known to peer (as advertised window less
924 * next expected input.) If the difference is at least two
925 * packets or at least 35% of the mximum possible window,
926 * then want to send a window update to peer.
929 u_short delta = 1 + cb->s_alo - cb->s_ack;
930 int adv = rcv_win - (delta * cb->s_mtu);
932 if ((so->so_rcv.sb_cc == 0 && adv >= (2 * cb->s_mtu)) ||
933 (100 * adv / so->so_rcv.sb_hiwat >= 35)) {
934 sppstat.spps_sndwinup++;
935 cb->s_flags |= SF_ACKNOW;
941 * Many comments from tcp_output.c are appropriate here
943 * If send window is too small, there is data to transmit, and no
944 * retransmit or persist is pending, then go to persist state.
945 * If nothing happens soon, send when timer expires:
946 * if window is nonzero, transmit what we can,
947 * otherwise send a probe.
949 if (so->so_snd.sb_cc && cb->s_timer[SPPT_REXMT] == 0 &&
950 cb->s_timer[SPPT_PERSIST] == 0) {
955 * No reason to send a packet, just return.
962 * Find requested packet.
966 cb->s_want = cb->s_snxt;
967 for (m = sb->sb_mb; m; m = m->m_act) {
968 si = mtod(m, struct spidp *);
969 if (SSEQ_LEQ(cb->s_snxt, si->si_seq))
974 if (si->si_seq == cb->s_snxt)
977 sppstat.spps_sndvoid++, si = 0;
985 alo = cb->s_ack - 1 + (rcv_win / ((short)cb->s_mtu));
986 if (SSEQ_LT(alo, cb->s_alo))
991 * must make a copy of this packet for
992 * idp_output to monkey with
994 m = m_copy(dtom(si), 0, (int)M_COPYALL);
998 si = mtod(m, struct spidp *);
999 if (SSEQ_LT(si->si_seq, cb->s_smax))
1000 sppstat.spps_sndrexmitpack++;
1002 sppstat.spps_sndpack++;
1003 } else if (cb->s_force || cb->s_flags & SF_ACKNOW) {
1005 * Must send an acknowledgement or a probe
1008 sppstat.spps_sndprobe++;
1009 if (cb->s_flags & SF_ACKNOW)
1010 sppstat.spps_sndacks++;
1011 m = m_gethdr(MB_DONTWAIT, MT_HEADER);
1015 * Fill in mbuf with extended SP header
1016 * and addresses and length put into network format.
1018 MH_ALIGN(m, sizeof (struct spidp));
1019 m->m_len = sizeof (*si);
1020 m->m_pkthdr.len = sizeof (*si);
1021 si = mtod(m, struct spidp *);
1022 si->si_i = *cb->s_idp;
1023 si->si_s = cb->s_shdr;
1024 si->si_seq = cb->s_smax + 1;
1025 si->si_len = htons(sizeof (*si));
1029 if (so->so_options & SO_DEBUG || traceallspps)
1030 spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
1034 * Stuff checksum and output datagram.
1036 if ((si->si_cc & SP_SP) == 0) {
1037 if (cb->s_force != (1 + SPPT_PERSIST) ||
1038 cb->s_timer[SPPT_PERSIST] == 0) {
1040 * If this is a new packet and we are not currently
1041 * timing anything, time this one.
1043 if (SSEQ_LT(cb->s_smax, si->si_seq)) {
1044 cb->s_smax = si->si_seq;
1045 if (cb->s_rtt == 0) {
1046 sppstat.spps_segstimed++;
1047 cb->s_rtseq = si->si_seq;
1052 * Set rexmt timer if not currently set,
1053 * Initial value for retransmit timer is smoothed
1054 * round-trip time + 2 * round-trip time variance.
1055 * Initialize shift counter which is used for backoff
1056 * of retransmit time.
1058 if (cb->s_timer[SPPT_REXMT] == 0 &&
1059 cb->s_snxt != cb->s_rack) {
1060 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1061 if (cb->s_timer[SPPT_PERSIST]) {
1062 cb->s_timer[SPPT_PERSIST] = 0;
1066 } else if (SSEQ_LT(cb->s_smax, si->si_seq)) {
1067 cb->s_smax = si->si_seq;
1069 } else if (cb->s_state < TCPS_ESTABLISHED) {
1071 cb->s_rtt = 1; /* Time initial handshake */
1072 if (cb->s_timer[SPPT_REXMT] == 0)
1073 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1077 * Do not request acks when we ack their data packets or
1078 * when we do a gratuitous window update.
1080 if (((si->si_cc & SP_SP) == 0) || cb->s_force)
1082 si->si_seq = htons(si->si_seq);
1083 si->si_alo = htons(alo);
1084 si->si_ack = htons(cb->s_ack);
1088 len = ntohs(si->si_len);
1091 si->si_sum = ns_cksum(m, len);
1093 si->si_sum = 0xffff;
1096 if (so->so_options & SO_DEBUG || traceallspps)
1097 spp_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
1099 if (so->so_options & SO_DONTROUTE)
1100 error = ns_output(m, (struct route *)0, NS_ROUTETOIF);
1102 error = ns_output(m, &cb->s_nspcb->nsp_route, 0);
1107 sppstat.spps_sndtotal++;
1109 * Data sent (as far as we can tell).
1110 * If this advertises a larger window than any other segment,
1111 * then remember the size of the advertized window.
1112 * Any pending ACK has now been sent.
1115 cb->s_flags &= ~(SF_ACKNOW|SF_DELACK);
1116 if (SSEQ_GT(alo, cb->s_alo))
1124 int spp_do_persist_panics = 0;
1130 int t = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
1132 if (cb->s_timer[SPPT_REXMT] && spp_do_persist_panics)
1133 panic("spp_output REXMT");
1135 * Start/restart persistance timer.
1137 SPPT_RANGESET(cb->s_timer[SPPT_PERSIST],
1138 t*spp_backoff[cb->s_rxtshift],
1139 SPPTV_PERSMIN, SPPTV_PERSMAX);
1140 if (cb->s_rxtshift < SPP_MAXRXTSHIFT)
1145 spp_ctloutput(req, so, level, name, value)
1149 struct mbuf **value;
1152 struct nspcb *nsp = sotonspcb(so);
1154 int mask, error = 0;
1156 if (level != NSPROTO_SPP) {
1157 /* This will have to be changed when we do more general
1158 stacking of protocols */
1159 return (idp_ctloutput(req, so, level, name, value));
1165 cb = nstosppcb(nsp);
1172 m = m_get(MB_DONTWAIT, MT_DATA);
1177 case SO_HEADERS_ON_INPUT:
1181 case SO_HEADERS_ON_OUTPUT:
1184 m->m_len = sizeof(short);
1185 *mtod(m, short *) = cb->s_flags & mask;
1189 m->m_len = sizeof(u_short);
1190 *mtod(m, short *) = cb->s_mtu;
1193 case SO_LAST_HEADER:
1194 m->m_len = sizeof(struct sphdr);
1195 *mtod(m, struct sphdr *) = cb->s_rhdr;
1198 case SO_DEFAULT_HEADERS:
1199 m->m_len = sizeof(struct spidp);
1200 *mtod(m, struct sphdr *) = cb->s_shdr;
1210 if (value == 0 || *value == 0) {
1217 case SO_HEADERS_ON_INPUT:
1221 case SO_HEADERS_ON_OUTPUT:
1224 if (cb->s_flags & SF_PI) {
1225 ok = mtod(*value, int *);
1227 cb->s_flags |= mask;
1229 cb->s_flags &= ~mask;
1230 } else error = EINVAL;
1234 cb->s_mtu = *(mtod(*value, u_short *));
1239 ok = mtod(*value, int *);
1241 cb->s_flags2 |= SF_NEWCALL;
1244 cb->s_flags2 &= ~SF_NEWCALL;
1250 case SO_DEFAULT_HEADERS:
1253 = mtod(*value, struct sphdr *);
1254 cb->s_dt = sp->sp_dt;
1255 cb->s_cc = sp->sp_cc & SP_EM;
1269 #warning "spp_usrreq not converted to FreeBSD usrreq style! watch out!"
1272 spp_usrreq(so, req, m, nam, controlp)
1275 struct mbuf *m, *nam, *controlp;
1278 #ifdef OBSOLETE /* not converted to FreeBSD usrreq style XXX */
1279 struct nspcb *nsp = sotonspcb(so);
1280 struct sppcb *cb = NULL;
1286 if (req == PRU_CONTROL)
1287 return (ns_control(so, (int)m, (caddr_t)nam,
1288 (struct ifnet *)controlp));
1290 if (req != PRU_ATTACH) {
1295 cb = nstosppcb(nsp);
1297 ostate = cb ? cb->s_state : 0;
1306 error = ns_pcballoc(so, &nspcb);
1309 if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
1310 error = soreserve(so, (u_long) 3072, (u_long) 3072);
1314 nsp = sotonspcb(so);
1317 mm = m_getclr(MB_DONTWAIT, MT_CONTROL);
1324 cb = mtod(mm, struct sppcb *);
1325 mm = m_getclr(MB_DONTWAIT, MT_HEADER);
1327 (void) m_free(dtom(m));
1331 cb->s_idp = mtod(mm, struct idp *);
1332 cb->s_state = TCPS_LISTEN;
1335 cb->s_q.si_next = cb->s_q.si_prev = &cb->s_q;
1337 cb->s_mtu = 576 - sizeof (struct spidp);
1338 cb->s_cwnd = sbspace(sb) * CUNIT / cb->s_mtu;
1339 cb->s_ssthresh = cb->s_cwnd;
1340 cb->s_cwmx = sbspace(sb) * CUNIT /
1341 (2 * sizeof (struct spidp));
1342 /* Above is recomputed when connecting to account
1343 for changed buffering or mtu's */
1344 cb->s_rtt = SPPTV_SRTTBASE;
1345 cb->s_rttvar = SPPTV_SRTTDFLT << 2;
1346 SPPT_RANGESET(cb->s_rxtcur,
1347 ((SPPTV_SRTTBASE >> 2) + (SPPTV_SRTTDFLT << 2)) >> 1,
1348 SPPTV_MIN, SPPTV_REXMTMAX);
1349 nsp->nsp_pcb = (caddr_t) cb;
1357 if (cb->s_state > TCPS_LISTEN)
1358 cb = spp_disconnect(cb);
1364 error = ns_pcbbind(nsp, nam);
1368 if (nsp->nsp_lport == 0)
1369 error = ns_pcbbind(nsp, (struct mbuf *)0);
1371 cb->s_state = TCPS_LISTEN;
1375 * Initiate connection to peer.
1376 * Enter SYN_SENT state, and mark socket as connecting.
1377 * Start keep-alive timer, setup prototype header,
1378 * Send initial system packet requesting connection.
1381 if (nsp->nsp_lport == 0) {
1382 error = ns_pcbbind(nsp, (struct mbuf *)0);
1386 error = ns_pcbconnect(nsp, nam);
1390 sppstat.spps_connattempt++;
1391 cb->s_state = TCPS_SYN_SENT;
1394 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
1395 cb->s_force = 1 + SPPTV_KEEP;
1397 * Other party is required to respond to
1398 * the port I send from, but he is not
1399 * required to answer from where I am sending to,
1400 * so allow wildcarding.
1401 * original port I am sending to is still saved in
1405 error = spp_output(cb, (struct mbuf *) 0);
1413 * We may decide later to implement connection closing
1414 * handshaking at the spp level optionally.
1415 * here is the hook to do it:
1417 case PRU_DISCONNECT:
1418 cb = spp_disconnect(cb);
1422 * Accept a connection. Essentially all the work is
1423 * done at higher levels; just return the address
1424 * of the peer, storing through addr.
1427 struct sockaddr_ns *sns = mtod(nam, struct sockaddr_ns *);
1429 nam->m_len = sizeof (struct sockaddr_ns);
1430 sns->sns_family = AF_NS;
1431 sns->sns_addr = nsp->nsp_faddr;
1437 cb = spp_usrclosed(cb);
1439 error = spp_output(cb, (struct mbuf *) 0);
1443 * After a receive, possibly send acknowledgment
1444 * updating allocation.
1447 cb->s_flags |= SF_RVD;
1448 (void) spp_output(cb, (struct mbuf *) 0);
1449 cb->s_flags &= ~SF_RVD;
1453 (void) spp_drop(cb, ECONNABORTED);
1463 if ((cb->s_oobflags & SF_IOOB) || so->so_oobmark ||
1464 (so->so_state & SS_RCVATMARK)) {
1466 *mtod(m, caddr_t) = cb->s_iobc;
1473 if (sbspace(&so->so_snd) < -512) {
1477 cb->s_oobflags |= SF_SOOB;
1481 u_short *p = mtod(controlp, u_short *);
1483 if ((p[0] == 5) && p[1] == 1) { /* XXXX, for testing */
1484 cb->s_shdr.sp_dt = *(u_char *)(&p[2]);
1490 error = spp_output(cb, m);
1495 ns_setsockaddr(nsp, nam);
1499 ns_setpeeraddr(nsp, nam);
1503 cb = spp_timers(cb, (int)nam);
1504 req |= ((int)nam) << 8;
1516 if (cb && (so->so_options & SO_DEBUG || traceallspps))
1517 spp_trace(SA_USER, (u_char)ostate, cb, (struct spidp *)0, req);
1519 if (controlp != NULL)
1529 spp_usrreq_sp(so, req, m, nam, controlp)
1532 struct mbuf *m, *nam, *controlp;
1534 int error = spp_usrreq(so, req, m, nam, controlp);
1536 if (req == PRU_ATTACH && error == 0) {
1537 struct nspcb *nsp = sotonspcb(so);
1538 ((struct sppcb *)nsp->nsp_pcb)->s_flags |=
1539 (SF_HI | SF_HO | SF_PI);
1545 * Create template to be used to send spp packets on a connection.
1546 * Called after host entry created, fills
1547 * in a skeletal spp header (choosing connection id),
1548 * minimizing the amount of work necessary when the connection is used.
1554 struct nspcb *nsp = cb->s_nspcb;
1555 struct idp *idp = cb->s_idp;
1556 struct sockbuf *sb = &(nsp->nsp_socket->so_snd);
1558 idp->idp_pt = NSPROTO_SPP;
1559 idp->idp_sna = nsp->nsp_laddr;
1560 idp->idp_dna = nsp->nsp_faddr;
1561 cb->s_sid = htons(spp_iss);
1562 spp_iss += SPP_ISSINCR/2;
1564 cb->s_cwnd = (sbspace(sb) * CUNIT) / cb->s_mtu;
1565 cb->s_ssthresh = cb->s_cwnd; /* Try to expand fast to full complement
1567 cb->s_cwmx = (sbspace(sb) * CUNIT) / (2 * sizeof(struct spidp));
1568 cb->s_cwmx = max(cb->s_cwmx, cb->s_cwnd);
1569 /* But allow for lots of little packets as well */
1573 * Close a SPIP control block:
1574 * discard spp control block itself
1575 * discard ns protocol control block
1576 * wake up any sleepers
1583 struct nspcb *nsp = cb->s_nspcb;
1584 struct socket *so = nsp->nsp_socket;
1587 s = cb->s_q.si_next;
1588 while (s != &(cb->s_q)) {
1590 m = dtom(s->si_prev);
1594 (void) m_free(dtom(cb->s_idp));
1595 (void) m_free(dtom(cb));
1597 soisdisconnected(so);
1599 sppstat.spps_closed++;
1600 return ((struct sppcb *)0);
1603 * Someday we may do level 3 handshaking
1604 * to close a connection or send a xerox style error.
1605 * For now, just close.
1611 return (spp_close(cb));
1617 return (spp_close(cb));
1620 * Drop connection, reporting
1621 * the specified error.
1628 struct socket *so = cb->s_nspcb->nsp_socket;
1631 * someday, in the xerox world
1632 * we will generate error protocol packets
1633 * announcing that the socket has gone away.
1635 if (TCPS_HAVERCVDSYN(cb->s_state)) {
1636 sppstat.spps_drops++;
1637 cb->s_state = TCPS_CLOSED;
1638 /*(void) tcp_output(cb);*/
1640 sppstat.spps_conndrops++;
1641 so->so_error = errno;
1642 return (spp_close(cb));
1650 (void) spp_close((struct sppcb *)nsp->nsp_pcb);
1654 * Fast timeout routine for processing delayed acks
1663 nsp = nspcb.nsp_next;
1665 for (; nsp != &nspcb; nsp = nsp->nsp_next)
1666 if ((cb = (struct sppcb *)nsp->nsp_pcb) &&
1667 (cb->s_flags & SF_DELACK)) {
1668 cb->s_flags &= ~SF_DELACK;
1669 cb->s_flags |= SF_ACKNOW;
1670 sppstat.spps_delack++;
1671 (void) spp_output(cb, (struct mbuf *) 0);
1677 * spp protocol timeout routine called every 500 ms.
1678 * Updates the timers in all active pcb's and
1679 * causes finite state machine actions if timers expire.
1684 struct nspcb *ip, *ipnxt;
1690 * Search through tcb's and update active timers.
1692 ip = nspcb.nsp_next;
1697 while (ip != &nspcb) {
1699 ipnxt = ip->nsp_next;
1702 for (i = 0; i < SPPT_NTIMERS; i++) {
1703 if (cb->s_timer[i] && --cb->s_timer[i] == 0) {
1704 (void) spp_usrreq(cb->s_nspcb->nsp_socket,
1705 PRU_SLOWTIMO, (struct mbuf *)0,
1706 (struct mbuf *)i, (struct mbuf *)0);
1707 if (ipnxt->nsp_prev != ip)
1717 spp_iss += SPP_ISSINCR/PR_SLOWHZ; /* increment iss */
1721 * SPP timer processing.
1724 spp_timers(cb, timer)
1731 cb->s_force = 1 + timer;
1735 * 2 MSL timeout in shutdown went off. TCP deletes connection
1739 printf("spp: SPPT_2MSL went off for no reason\n");
1740 cb->s_timer[timer] = 0;
1744 * Retransmission timer went off. Message has not
1745 * been acked within retransmit interval. Back off
1746 * to a longer retransmit interval and retransmit one packet.
1749 if (++cb->s_rxtshift > SPP_MAXRXTSHIFT) {
1750 cb->s_rxtshift = SPP_MAXRXTSHIFT;
1751 sppstat.spps_timeoutdrop++;
1752 cb = spp_drop(cb, ETIMEDOUT);
1755 sppstat.spps_rexmttimeo++;
1756 rexmt = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
1757 rexmt *= spp_backoff[cb->s_rxtshift];
1758 SPPT_RANGESET(cb->s_rxtcur, rexmt, SPPTV_MIN, SPPTV_REXMTMAX);
1759 cb->s_timer[SPPT_REXMT] = cb->s_rxtcur;
1761 * If we have backed off fairly far, our srtt
1762 * estimate is probably bogus. Clobber it
1763 * so we'll take the next rtt measurement as our srtt;
1764 * move the current srtt into rttvar to keep the current
1765 * retransmit times until then.
1767 if (cb->s_rxtshift > SPP_MAXRXTSHIFT / 4 ) {
1768 cb->s_rttvar += (cb->s_srtt >> 2);
1771 cb->s_snxt = cb->s_rack;
1773 * If timing a packet, stop the timer.
1777 * See very long discussion in tcp_timer.c about congestion
1778 * window and sstrhesh
1780 win = min(cb->s_swnd, (cb->s_cwnd/CUNIT)) / 2;
1784 cb->s_ssthresh = win * CUNIT;
1785 (void) spp_output(cb, (struct mbuf *) 0);
1789 * Persistance timer into zero window.
1790 * Force a probe to be sent.
1793 sppstat.spps_persisttimeo++;
1795 (void) spp_output(cb, (struct mbuf *) 0);
1799 * Keep-alive timer went off; send something
1800 * or drop connection if idle for too long.
1803 sppstat.spps_keeptimeo++;
1804 if (cb->s_state < TCPS_ESTABLISHED)
1806 if (cb->s_nspcb->nsp_socket->so_options & SO_KEEPALIVE) {
1807 if (cb->s_idle >= SPPTV_MAXIDLE)
1809 sppstat.spps_keepprobe++;
1810 (void) spp_output(cb, (struct mbuf *) 0);
1813 cb->s_timer[SPPT_KEEP] = SPPTV_KEEP;
1816 sppstat.spps_keepdrops++;
1817 cb = spp_drop(cb, ETIMEDOUT);
1823 int SppcbSize = sizeof (struct sppcb);
1824 int NspcbSize = sizeof (struct nspcb);