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0daccb9c94
freebsd-dev/sys/netipx/spx_usrreq.c
Robert Watson 0daccb9c94 In the current world order, solisten() implements the state transition of 
a socket from a regular socket to a listening socket able to accept new
connections.  As part of this state transition, solisten() calls into the
protocol to update protocol-layer state.  There were several bugs in this
implementation that could result in a race wherein a TCP SYN received
in the interval between the protocol state transition and the shortly
following socket layer transition would result in a panic in the TCP code,
as the socket would be in the TCPS_LISTEN state, but the socket would not
have the SO_ACCEPTCONN flag set.

This change does the following:

- Pushes the socket state transition from the socket layer solisten() to
  to socket "library" routines called from the protocol.  This permits
  the socket routines to be called while holding the protocol mutexes,
  preventing a race exposing the incomplete socket state transition to TCP
  after the TCP state transition has completed.  The check for a socket
  layer state transition is performed by solisten_proto_check(), and the
  actual transition is performed by solisten_proto().

- Holds the socket lock for the duration of the socket state test and set,
  and over the protocol layer state transition, which is now possible as
  the socket lock is acquired by the protocol layer, rather than vice
  versa.  This prevents additional state related races in the socket
  layer.

This permits the dual transition of socket layer and protocol layer state
to occur while holding locks for both layers, making the two changes
atomic with respect to one another.  Similar changes are likely require
elsewhere in the socket/protocol code.

Reported by:		Peter Holm <peter@holm.cc>
Review and fixes from:	emax, Antoine Brodin <antoine.brodin@laposte.net>
Philosophical head nod:	gnn
2005-02-21 21:58:17 +00:00

1982 lines
46 KiB
C
Raw Blame History

/*-
* Copyright (c) 2004-2005 Robert N. M. Watson
* Copyright (c) 1995, Mike Mitchell
* Copyright (c) 1984, 1985, 1986, 1987, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)spx_usrreq.h
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/protosw.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sx.h>
#include <sys/systm.h>
#include <net/route.h>
#include <netinet/tcp_fsm.h>
#include <netipx/ipx.h>
#include <netipx/ipx_pcb.h>
#include <netipx/ipx_var.h>
#include <netipx/spx.h>
#include <netipx/spx_debug.h>
#include <netipx/spx_timer.h>
#include <netipx/spx_var.h>
/*
* SPX protocol implementation.
*/
static u_short spx_iss;
static u_short spx_newchecks[50];
static int spx_hardnosed;
static int spx_use_delack = 0;
static int traceallspxs = 0;
static struct spx spx_savesi;
static struct spx_istat spx_istat;
/* Following was struct spxstat spxstat; */
#ifndef spxstat
#define spxstat spx_istat.newstats
#endif
static const int spx_backoff[SPX_MAXRXTSHIFT+1] =
{ 1, 2, 4, 8, 16, 32, 64, 64, 64, 64, 64, 64, 64 };
static void spx_close(struct spxpcb *cb);
static void spx_disconnect(struct spxpcb *cb);
static void spx_drop(struct spxpcb *cb, int errno);
static int spx_output(struct spxpcb *cb, struct mbuf *m0);
static int spx_reass(struct spxpcb *cb, struct spx *si);
static void spx_setpersist(struct spxpcb *cb);
static void spx_template(struct spxpcb *cb);
static struct spxpcb *spx_timers(struct spxpcb *cb, int timer);
static void spx_usrclosed(struct spxpcb *cb);
static int spx_usr_abort(struct socket *so);
static int spx_accept(struct socket *so, struct sockaddr **nam);
static int spx_attach(struct socket *so, int proto, struct thread *td);
static int spx_bind(struct socket *so, struct sockaddr *nam, struct thread *td);
static int spx_connect(struct socket *so, struct sockaddr *nam,
struct thread *td);
static int spx_detach(struct socket *so);
static int spx_usr_disconnect(struct socket *so);
static int spx_listen(struct socket *so, struct thread *td);
static int spx_rcvd(struct socket *so, int flags);
static int spx_rcvoob(struct socket *so, struct mbuf *m, int flags);
static int spx_send(struct socket *so, int flags, struct mbuf *m,
struct sockaddr *addr, struct mbuf *control,
struct thread *td);
static int spx_shutdown(struct socket *so);
static int spx_sp_attach(struct socket *so, int proto, struct thread *td);
struct pr_usrreqs spx_usrreqs = {
.pru_abort = spx_usr_abort,
.pru_accept = spx_accept,
.pru_attach = spx_attach,
.pru_bind = spx_bind,
.pru_connect = spx_connect,
.pru_control = ipx_control,
.pru_detach = spx_detach,
.pru_disconnect = spx_usr_disconnect,
.pru_listen = spx_listen,
.pru_peeraddr = ipx_peeraddr,
.pru_rcvd = spx_rcvd,
.pru_rcvoob = spx_rcvoob,
.pru_send = spx_send,
.pru_shutdown = spx_shutdown,
.pru_sockaddr = ipx_sockaddr,
};
struct pr_usrreqs spx_usrreq_sps = {
.pru_abort = spx_usr_abort,
.pru_accept = spx_accept,
.pru_attach = spx_sp_attach,
.pru_bind = spx_bind,
.pru_connect = spx_connect,
.pru_control = ipx_control,
.pru_detach = spx_detach,
.pru_disconnect = spx_usr_disconnect,
.pru_listen = spx_listen,
.pru_peeraddr = ipx_peeraddr,
.pru_rcvd = spx_rcvd,
.pru_rcvoob = spx_rcvoob,
.pru_send = spx_send,
.pru_shutdown = spx_shutdown,
.pru_sockaddr = ipx_sockaddr,
};
void
spx_init()
{
spx_iss = 1; /* WRONG !! should fish it out of TODR */
}
void
spx_input(m, ipxp)
register struct mbuf *m;
register struct ipxpcb *ipxp;
{
register struct spxpcb *cb;
register struct spx *si = mtod(m, struct spx *);
register struct socket *so;
int dropsocket = 0;
short ostate = 0;
spxstat.spxs_rcvtotal++;
KASSERT(ipxp != NULL, ("spx_input: NULL ipxpcb"));
/*
* spx_input() assumes that the caller will hold both the pcb list
* lock and also the ipxp lock. spx_input() will release both before
* returning, and may in fact trade in the ipxp lock for another pcb
* lock following sonewconn().
*/
IPX_LIST_LOCK_ASSERT();
IPX_LOCK_ASSERT(ipxp);
cb = ipxtospxpcb(ipxp);
if (cb == NULL)
goto bad;
if (m->m_len < sizeof(*si)) {
if ((m = m_pullup(m, sizeof(*si))) == NULL) {
IPX_UNLOCK(ipxp);
IPX_LIST_UNLOCK();
spxstat.spxs_rcvshort++;
return;
}
si = mtod(m, struct spx *);
}
si->si_seq = ntohs(si->si_seq);
si->si_ack = ntohs(si->si_ack);
si->si_alo = ntohs(si->si_alo);
so = ipxp->ipxp_socket;
if (so->so_options & SO_DEBUG || traceallspxs) {
ostate = cb->s_state;
spx_savesi = *si;
}
if (so->so_options & SO_ACCEPTCONN) {
struct spxpcb *ocb = cb;
so = sonewconn(so, 0);
if (so == NULL) {
goto drop;
}
/*
* This is ugly, but ....
*
* Mark socket as temporary until we're
* committed to keeping it. The code at
* ``drop'' and ``dropwithreset'' check the
* flag dropsocket to see if the temporary
* socket created here should be discarded.
* We mark the socket as discardable until
* we're committed to it below in TCPS_LISTEN.
*/
dropsocket++;
IPX_UNLOCK(ipxp);
ipxp = (struct ipxpcb *)so->so_pcb;
IPX_LOCK(ipxp);
ipxp->ipxp_laddr = si->si_dna;
cb = ipxtospxpcb(ipxp);
cb->s_mtu = ocb->s_mtu; /* preserve sockopts */
cb->s_flags = ocb->s_flags; /* preserve sockopts */
cb->s_flags2 = ocb->s_flags2; /* preserve sockopts */
cb->s_state = TCPS_LISTEN;
}
/*
* Packet received on connection.
* reset idle time and keep-alive timer;
*/
cb->s_idle = 0;
cb->s_timer[SPXT_KEEP] = SPXTV_KEEP;
switch (cb->s_state) {
case TCPS_LISTEN:{
struct sockaddr_ipx *sipx, ssipx;
struct ipx_addr laddr;
/*
* If somebody here was carying on a conversation
* and went away, and his pen pal thinks he can
* still talk, we get the misdirected packet.
*/
if (spx_hardnosed && (si->si_did != 0 || si->si_seq != 0)) {
spx_istat.gonawy++;
goto dropwithreset;
}
sipx = &ssipx;
bzero(sipx, sizeof *sipx);
sipx->sipx_len = sizeof(*sipx);
sipx->sipx_family = AF_IPX;
sipx->sipx_addr = si->si_sna;
laddr = ipxp->ipxp_laddr;
if (ipx_nullhost(laddr))
ipxp->ipxp_laddr = si->si_dna;
if (ipx_pcbconnect(ipxp, (struct sockaddr *)sipx, &thread0)) {
ipxp->ipxp_laddr = laddr;
spx_istat.noconn++;
goto drop;
}
spx_template(cb);
dropsocket = 0; /* committed to socket */
cb->s_did = si->si_sid;
cb->s_rack = si->si_ack;
cb->s_ralo = si->si_alo;
#define THREEWAYSHAKE
#ifdef THREEWAYSHAKE
cb->s_state = TCPS_SYN_RECEIVED;
cb->s_force = 1 + SPXT_KEEP;
spxstat.spxs_accepts++;
cb->s_timer[SPXT_KEEP] = SPXTV_KEEP;
}
break;
/*
* This state means that we have heard a response
* to our acceptance of their connection
* It is probably logically unnecessary in this
* implementation.
*/
case TCPS_SYN_RECEIVED: {
if (si->si_did != cb->s_sid) {
spx_istat.wrncon++;
goto drop;
}
#endif
ipxp->ipxp_fport = si->si_sport;
cb->s_timer[SPXT_REXMT] = 0;
cb->s_timer[SPXT_KEEP] = SPXTV_KEEP;
soisconnected(so);
cb->s_state = TCPS_ESTABLISHED;
spxstat.spxs_accepts++;
}
break;
/*
* This state means that we have gotten a response
* to our attempt to establish a connection.
* We fill in the data from the other side,
* telling us which port to respond to, instead of the well-
* known one we might have sent to in the first place.
* We also require that this is a response to our
* connection id.
*/
case TCPS_SYN_SENT:
if (si->si_did != cb->s_sid) {
spx_istat.notme++;
goto drop;
}
spxstat.spxs_connects++;
cb->s_did = si->si_sid;
cb->s_rack = si->si_ack;
cb->s_ralo = si->si_alo;
cb->s_dport = ipxp->ipxp_fport = si->si_sport;
cb->s_timer[SPXT_REXMT] = 0;
cb->s_flags |= SF_ACKNOW;
soisconnected(so);
cb->s_state = TCPS_ESTABLISHED;
/* Use roundtrip time of connection request for initial rtt */
if (cb->s_rtt) {
cb->s_srtt = cb->s_rtt << 3;
cb->s_rttvar = cb->s_rtt << 1;
SPXT_RANGESET(cb->s_rxtcur,
((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
SPXTV_MIN, SPXTV_REXMTMAX);
cb->s_rtt = 0;
}
}
if (so->so_options & SO_DEBUG || traceallspxs)
spx_trace(SA_INPUT, (u_char)ostate, cb, &spx_savesi, 0);
m->m_len -= sizeof(struct ipx);
m->m_pkthdr.len -= sizeof(struct ipx);
m->m_data += sizeof(struct ipx);
if (spx_reass(cb, si)) {
m_freem(m);
}
if (cb->s_force || (cb->s_flags & (SF_ACKNOW|SF_WIN|SF_RXT)))
spx_output(cb, NULL);
cb->s_flags &= ~(SF_WIN|SF_RXT);
IPX_UNLOCK(ipxp);
IPX_LIST_UNLOCK();
return;
dropwithreset:
IPX_UNLOCK(ipxp);
if (dropsocket) {
struct socket *head;
ACCEPT_LOCK();
KASSERT((so->so_qstate & SQ_INCOMP) != 0,
("spx_input: nascent socket not SQ_INCOMP on soabort()"));
head = so->so_head;
TAILQ_REMOVE(&head->so_incomp, so, so_list);
head->so_incqlen--;
so->so_qstate &= ~SQ_INCOMP;
so->so_head = NULL;
ACCEPT_UNLOCK();
soabort(so);
cb = NULL;
}
IPX_LIST_UNLOCK();
si->si_seq = ntohs(si->si_seq);
si->si_ack = ntohs(si->si_ack);
si->si_alo = ntohs(si->si_alo);
m_freem(dtom(si));
if (cb == NULL || cb->s_ipxpcb->ipxp_socket->so_options & SO_DEBUG ||
traceallspxs)
spx_trace(SA_DROP, (u_char)ostate, cb, &spx_savesi, 0);
return;
drop:
bad:
if (cb == NULL || cb->s_ipxpcb->ipxp_socket->so_options & SO_DEBUG ||
traceallspxs)
spx_trace(SA_DROP, (u_char)ostate, cb, &spx_savesi, 0);
IPX_UNLOCK(ipxp);
IPX_LIST_UNLOCK();
m_freem(m);
}
static int spxrexmtthresh = 3;
/*
* This is structurally similar to the tcp reassembly routine
* but its function is somewhat different: It merely queues
* packets up, and suppresses duplicates.
*/
static int
spx_reass(cb, si)
register struct spxpcb *cb;
register struct spx *si;
{
register struct spx_q *q;
register struct mbuf *m;
register struct socket *so = cb->s_ipxpcb->ipxp_socket;
char packetp = cb->s_flags & SF_HI;
int incr;
char wakeup = 0;
IPX_LOCK_ASSERT(cb->s_ipxpcb);
if (si == SI(0))
goto present;
/*
* Update our news from them.
*/
if (si->si_cc & SPX_SA)
cb->s_flags |= (spx_use_delack ? SF_DELACK : SF_ACKNOW);
if (SSEQ_GT(si->si_alo, cb->s_ralo))
cb->s_flags |= SF_WIN;
if (SSEQ_LEQ(si->si_ack, cb->s_rack)) {
if ((si->si_cc & SPX_SP) && cb->s_rack != (cb->s_smax + 1)) {
spxstat.spxs_rcvdupack++;
/*
* If this is a completely duplicate ack
* and other conditions hold, we assume
* a packet has been dropped and retransmit
* it exactly as in tcp_input().
*/
if (si->si_ack != cb->s_rack ||
si->si_alo != cb->s_ralo)
cb->s_dupacks = 0;
else if (++cb->s_dupacks == spxrexmtthresh) {
u_short onxt = cb->s_snxt;
int cwnd = cb->s_cwnd;
cb->s_snxt = si->si_ack;
cb->s_cwnd = CUNIT;
cb->s_force = 1 + SPXT_REXMT;
spx_output(cb, NULL);
cb->s_timer[SPXT_REXMT] = cb->s_rxtcur;
cb->s_rtt = 0;
if (cwnd >= 4 * CUNIT)
cb->s_cwnd = cwnd / 2;
if (SSEQ_GT(onxt, cb->s_snxt))
cb->s_snxt = onxt;
return (1);
}
} else
cb->s_dupacks = 0;
goto update_window;
}
cb->s_dupacks = 0;
/*
* If our correspondent acknowledges data we haven't sent
* TCP would drop the packet after acking. We'll be a little
* more permissive
*/
if (SSEQ_GT(si->si_ack, (cb->s_smax + 1))) {
spxstat.spxs_rcvacktoomuch++;
si->si_ack = cb->s_smax + 1;
}
spxstat.spxs_rcvackpack++;
/*
* If transmit timer is running and timed sequence
* number was acked, update smoothed round trip time.
* See discussion of algorithm in tcp_input.c
*/
if (cb->s_rtt && SSEQ_GT(si->si_ack, cb->s_rtseq)) {
spxstat.spxs_rttupdated++;
if (cb->s_srtt != 0) {
register short delta;
delta = cb->s_rtt - (cb->s_srtt >> 3);
if ((cb->s_srtt += delta) <= 0)
cb->s_srtt = 1;
if (delta < 0)
delta = -delta;
delta -= (cb->s_rttvar >> 2);
if ((cb->s_rttvar += delta) <= 0)
cb->s_rttvar = 1;
} else {
/*
* No rtt measurement yet
*/
cb->s_srtt = cb->s_rtt << 3;
cb->s_rttvar = cb->s_rtt << 1;
}
cb->s_rtt = 0;
cb->s_rxtshift = 0;
SPXT_RANGESET(cb->s_rxtcur,
((cb->s_srtt >> 2) + cb->s_rttvar) >> 1,
SPXTV_MIN, SPXTV_REXMTMAX);
}
/*
* If all outstanding data is acked, stop retransmit
* timer and remember to restart (more output or persist).
* If there is more data to be acked, restart retransmit
* timer, using current (possibly backed-off) value;
*/
if (si->si_ack == cb->s_smax + 1) {
cb->s_timer[SPXT_REXMT] = 0;
cb->s_flags |= SF_RXT;
} else if (cb->s_timer[SPXT_PERSIST] == 0)
cb->s_timer[SPXT_REXMT] = cb->s_rxtcur;
/*
* When new data is acked, open the congestion window.
* If the window gives us less than ssthresh packets
* in flight, open exponentially (maxseg at a time).
* Otherwise open linearly (maxseg^2 / cwnd at a time).
*/
incr = CUNIT;
if (cb->s_cwnd > cb->s_ssthresh)
incr = max(incr * incr / cb->s_cwnd, 1);
cb->s_cwnd = min(cb->s_cwnd + incr, cb->s_cwmx);
/*
* Trim Acked data from output queue.
*/
SOCKBUF_LOCK(&so->so_snd);
while ((m = so->so_snd.sb_mb) != NULL) {
if (SSEQ_LT((mtod(m, struct spx *))->si_seq, si->si_ack))
sbdroprecord_locked(&so->so_snd);
else
break;
}
sowwakeup_locked(so);
cb->s_rack = si->si_ack;
update_window:
if (SSEQ_LT(cb->s_snxt, cb->s_rack))
cb->s_snxt = cb->s_rack;
if (SSEQ_LT(cb->s_swl1, si->si_seq) || ((cb->s_swl1 == si->si_seq &&
(SSEQ_LT(cb->s_swl2, si->si_ack))) ||
(cb->s_swl2 == si->si_ack && SSEQ_LT(cb->s_ralo, si->si_alo)))) {
/* keep track of pure window updates */
if ((si->si_cc & SPX_SP) && cb->s_swl2 == si->si_ack
&& SSEQ_LT(cb->s_ralo, si->si_alo)) {
spxstat.spxs_rcvwinupd++;
spxstat.spxs_rcvdupack--;
}
cb->s_ralo = si->si_alo;
cb->s_swl1 = si->si_seq;
cb->s_swl2 = si->si_ack;
cb->s_swnd = (1 + si->si_alo - si->si_ack);
if (cb->s_swnd > cb->s_smxw)
cb->s_smxw = cb->s_swnd;
cb->s_flags |= SF_WIN;
}
/*
* If this packet number is higher than that which
* we have allocated refuse it, unless urgent
*/
if (SSEQ_GT(si->si_seq, cb->s_alo)) {
if (si->si_cc & SPX_SP) {
spxstat.spxs_rcvwinprobe++;
return (1);
} else
spxstat.spxs_rcvpackafterwin++;
if (si->si_cc & SPX_OB) {
if (SSEQ_GT(si->si_seq, cb->s_alo + 60)) {
m_freem(dtom(si));
return (0);
} /* else queue this packet; */
} else {
#ifdef BROKEN
/*
* XXXRW: This is broken on at least one count:
* spx_close() will free the ipxp and related parts,
* which are then touched by spx_input() after the
* return from spx_reass().
*/
/*register struct socket *so = cb->s_ipxpcb->ipxp_socket;
if (so->so_state && SS_NOFDREF) {
spx_close(cb);
} else
would crash system*/
#endif
spx_istat.notyet++;
m_freem(dtom(si));
return (0);
}
}
/*
* If this is a system packet, we don't need to
* queue it up, and won't update acknowledge #
*/
if (si->si_cc & SPX_SP) {
return (1);
}
/*
* We have already seen this packet, so drop.
*/
if (SSEQ_LT(si->si_seq, cb->s_ack)) {
spx_istat.bdreas++;
spxstat.spxs_rcvduppack++;
if (si->si_seq == cb->s_ack - 1)
spx_istat.lstdup++;
return (1);
}
/*
* Loop through all packets queued up to insert in
* appropriate sequence.
*/
for (q = cb->s_q.si_next; q != &cb->s_q; q = q->si_next) {
if (si->si_seq == SI(q)->si_seq) {
spxstat.spxs_rcvduppack++;
return (1);
}
if (SSEQ_LT(si->si_seq, SI(q)->si_seq)) {
spxstat.spxs_rcvoopack++;
break;
}
}
insque(si, q->si_prev);
/*
* If this packet is urgent, inform process
*/
if (si->si_cc & SPX_OB) {
cb->s_iobc = ((char *)si)[1 + sizeof(*si)];
sohasoutofband(so);
cb->s_oobflags |= SF_IOOB;
}
present:
#define SPINC sizeof(struct spxhdr)
SOCKBUF_LOCK(&so->so_rcv);
/*
* Loop through all packets queued up to update acknowledge
* number, and present all acknowledged data to user;
* If in packet interface mode, show packet headers.
*/
for (q = cb->s_q.si_next; q != &cb->s_q; q = q->si_next) {
if (SI(q)->si_seq == cb->s_ack) {
cb->s_ack++;
m = dtom(q);
if (SI(q)->si_cc & SPX_OB) {
cb->s_oobflags &= ~SF_IOOB;
if (so->so_rcv.sb_cc)
so->so_oobmark = so->so_rcv.sb_cc;
else
so->so_rcv.sb_state |= SBS_RCVATMARK;
}
q = q->si_prev;
remque(q->si_next);
wakeup = 1;
spxstat.spxs_rcvpack++;
#ifdef SF_NEWCALL
if (cb->s_flags2 & SF_NEWCALL) {
struct spxhdr *sp = mtod(m, struct spxhdr *);
u_char dt = sp->spx_dt;
spx_newchecks[4]++;
if (dt != cb->s_rhdr.spx_dt) {
struct mbuf *mm =
m_getclr(M_DONTWAIT, MT_CONTROL);
spx_newchecks[0]++;
if (mm != NULL) {
u_short *s =
mtod(mm, u_short *);
cb->s_rhdr.spx_dt = dt;
mm->m_len = 5; /*XXX*/
s[0] = 5;
s[1] = 1;
*(u_char *)(&s[2]) = dt;
sbappend_locked(&so->so_rcv, mm);
}
}
if (sp->spx_cc & SPX_OB) {
MCHTYPE(m, MT_OOBDATA);
spx_newchecks[1]++;
so->so_oobmark = 0;
so->so_rcv.sb_state &= ~SBS_RCVATMARK;
}
if (packetp == 0) {
m->m_data += SPINC;
m->m_len -= SPINC;
m->m_pkthdr.len -= SPINC;
}
if ((sp->spx_cc & SPX_EM) || packetp) {
sbappendrecord_locked(&so->so_rcv, m);
spx_newchecks[9]++;
} else
sbappend_locked(&so->so_rcv, m);
} else
#endif
if (packetp) {
sbappendrecord_locked(&so->so_rcv, m);
} else {
cb->s_rhdr = *mtod(m, struct spxhdr *);
m->m_data += SPINC;
m->m_len -= SPINC;
m->m_pkthdr.len -= SPINC;
sbappend_locked(&so->so_rcv, m);
}
} else
break;
}
if (wakeup)
sorwakeup_locked(so);
else
SOCKBUF_UNLOCK(&so->so_rcv);
return (0);
}
void
spx_ctlinput(cmd, arg_as_sa, dummy)
int cmd;
struct sockaddr *arg_as_sa; /* XXX should be swapped with dummy */
void *dummy;
{
caddr_t arg = (/* XXX */ caddr_t)arg_as_sa;
struct ipx_addr *na;
struct sockaddr_ipx *sipx;
if (cmd < 0 || cmd >= PRC_NCMDS)
return;
switch (cmd) {
case PRC_ROUTEDEAD:
return;
case PRC_IFDOWN:
case PRC_HOSTDEAD:
case PRC_HOSTUNREACH:
sipx = (struct sockaddr_ipx *)arg;
if (sipx->sipx_family != AF_IPX)
return;
na = &sipx->sipx_addr;
break;
default:
break;
}
}
static int
spx_output(cb, m0)
register struct spxpcb *cb;
struct mbuf *m0;
{
struct socket *so = cb->s_ipxpcb->ipxp_socket;
register struct mbuf *m;
register struct spx *si = NULL;
register struct sockbuf *sb = &so->so_snd;
int len = 0, win, rcv_win;
short span, off, recordp = 0;
u_short alo;
int error = 0, sendalot;
#ifdef notdef
int idle;
#endif
struct mbuf *mprev;
IPX_LOCK_ASSERT(cb->s_ipxpcb);
if (m0 != NULL) {
int mtu = cb->s_mtu;
int datalen;
/*
* Make sure that packet isn't too big.
*/
for (m = m0; m != NULL; m = m->m_next) {
mprev = m;
len += m->m_len;
if (m->m_flags & M_EOR)
recordp = 1;
}
datalen = (cb->s_flags & SF_HO) ?
len - sizeof(struct spxhdr) : len;
if (datalen > mtu) {
if (cb->s_flags & SF_PI) {
m_freem(m0);
return (EMSGSIZE);
} else {
int oldEM = cb->s_cc & SPX_EM;
cb->s_cc &= ~SPX_EM;
while (len > mtu) {
/*
* Here we are only being called
* from usrreq(), so it is OK to
* block.
*/
m = m_copym(m0, 0, mtu, M_TRYWAIT);
if (cb->s_flags & SF_NEWCALL) {
struct mbuf *mm = m;
spx_newchecks[7]++;
while (mm != NULL) {
mm->m_flags &= ~M_EOR;
mm = mm->m_next;
}
}
error = spx_output(cb, m);
if (error) {
cb->s_cc |= oldEM;
m_freem(m0);
return (error);
}
m_adj(m0, mtu);
len -= mtu;
}
cb->s_cc |= oldEM;
}
}
/*
* Force length even, by adding a "garbage byte" if
* necessary.
*/
if (len & 1) {
m = mprev;
if (M_TRAILINGSPACE(m) >= 1)
m->m_len++;
else {
struct mbuf *m1 = m_get(M_DONTWAIT, MT_DATA);
if (m1 == NULL) {
m_freem(m0);
return (ENOBUFS);
}
m1->m_len = 1;
*(mtod(m1, u_char *)) = 0;
m->m_next = m1;
}
}
m = m_gethdr(M_DONTWAIT, MT_HEADER);
if (m == NULL) {
m_freem(m0);
return (ENOBUFS);
}
/*
* Fill in mbuf with extended SP header
* and addresses and length put into network format.
*/
MH_ALIGN(m, sizeof(struct spx));
m->m_len = sizeof(struct spx);
m->m_next = m0;
si = mtod(m, struct spx *);
si->si_i = *cb->s_ipx;
si->si_s = cb->s_shdr;
if ((cb->s_flags & SF_PI) && (cb->s_flags & SF_HO)) {
register struct spxhdr *sh;
if (m0->m_len < sizeof(*sh)) {
if((m0 = m_pullup(m0, sizeof(*sh))) == NULL) {
m_free(m);
m_freem(m0);
return (EINVAL);
}
m->m_next = m0;
}
sh = mtod(m0, struct spxhdr *);
si->si_dt = sh->spx_dt;
si->si_cc |= sh->spx_cc & SPX_EM;
m0->m_len -= sizeof(*sh);
m0->m_data += sizeof(*sh);
len -= sizeof(*sh);
}
len += sizeof(*si);
if ((cb->s_flags2 & SF_NEWCALL) && recordp) {
si->si_cc |= SPX_EM;
spx_newchecks[8]++;
}
if (cb->s_oobflags & SF_SOOB) {
/*
* Per jqj@cornell:
* make sure OB packets convey exactly 1 byte.
* If the packet is 1 byte or larger, we
* have already guaranted there to be at least
* one garbage byte for the checksum, and
* extra bytes shouldn't hurt!
*/
if (len > sizeof(*si)) {
si->si_cc |= SPX_OB;
len = (1 + sizeof(*si));
}
}
si->si_len = htons((u_short)len);
m->m_pkthdr.len = ((len - 1) | 1) + 1;
/*
* queue stuff up for output
*/
sbappendrecord(sb, m);
cb->s_seq++;
}
#ifdef notdef
idle = (cb->s_smax == (cb->s_rack - 1));
#endif
again:
sendalot = 0;
off = cb->s_snxt - cb->s_rack;
win = min(cb->s_swnd, (cb->s_cwnd / CUNIT));
/*
* If in persist timeout with window of 0, send a probe.
* Otherwise, if window is small but nonzero
* and timer expired, send what we can and go into
* transmit state.
*/
if (cb->s_force == 1 + SPXT_PERSIST) {
if (win != 0) {
cb->s_timer[SPXT_PERSIST] = 0;
cb->s_rxtshift = 0;
}
}
span = cb->s_seq - cb->s_rack;
len = min(span, win) - off;
if (len < 0) {
/*
* Window shrank after we went into it.
* If window shrank to 0, cancel pending
* restransmission and pull s_snxt back
* to (closed) window. We will enter persist
* state below. If the widndow didn't close completely,
* just wait for an ACK.
*/
len = 0;
if (win == 0) {
cb->s_timer[SPXT_REXMT] = 0;
cb->s_snxt = cb->s_rack;
}
}
if (len > 1)
sendalot = 1;
rcv_win = sbspace(&so->so_rcv);
/*
* Send if we owe peer an ACK.
*/
if (cb->s_oobflags & SF_SOOB) {
/*
* must transmit this out of band packet
*/
cb->s_oobflags &= ~ SF_SOOB;
sendalot = 1;
spxstat.spxs_sndurg++;
goto found;
}
if (cb->s_flags & SF_ACKNOW)
goto send;
if (cb->s_state < TCPS_ESTABLISHED)
goto send;
/*
* Silly window can't happen in spx.
* Code from tcp deleted.
*/
if (len)
goto send;
/*
* Compare available window to amount of window
* known to peer (as advertised window less
* next expected input.) If the difference is at least two
* packets or at least 35% of the mximum possible window,
* then want to send a window update to peer.
*/
if (rcv_win > 0) {
u_short delta = 1 + cb->s_alo - cb->s_ack;
int adv = rcv_win - (delta * cb->s_mtu);
if ((so->so_rcv.sb_cc == 0 && adv >= (2 * cb->s_mtu)) ||
(100 * adv / so->so_rcv.sb_hiwat >= 35)) {
spxstat.spxs_sndwinup++;
cb->s_flags |= SF_ACKNOW;
goto send;
}
}
/*
* Many comments from tcp_output.c are appropriate here
* including . . .
* If send window is too small, there is data to transmit, and no
* retransmit or persist is pending, then go to persist state.
* If nothing happens soon, send when timer expires:
* if window is nonzero, transmit what we can,
* otherwise send a probe.
*/
if (so->so_snd.sb_cc && cb->s_timer[SPXT_REXMT] == 0 &&
cb->s_timer[SPXT_PERSIST] == 0) {
cb->s_rxtshift = 0;
spx_setpersist(cb);
}
/*
* No reason to send a packet, just return.
*/
cb->s_outx = 1;
return (0);
send:
/*
* Find requested packet.
*/
si = 0;
if (len > 0) {
cb->s_want = cb->s_snxt;
for (m = sb->sb_mb; m != NULL; m = m->m_act) {
si = mtod(m, struct spx *);
if (SSEQ_LEQ(cb->s_snxt, si->si_seq))
break;
}
found:
if (si != NULL) {
if (si->si_seq == cb->s_snxt)
cb->s_snxt++;
else
spxstat.spxs_sndvoid++, si = 0;
}
}
/*
* update window
*/
if (rcv_win < 0)
rcv_win = 0;
alo = cb->s_ack - 1 + (rcv_win / ((short)cb->s_mtu));
if (SSEQ_LT(alo, cb->s_alo))
alo = cb->s_alo;
if (si != NULL) {
/*
* must make a copy of this packet for
* ipx_output to monkey with
*/
m = m_copy(dtom(si), 0, (int)M_COPYALL);
if (m == NULL) {
return (ENOBUFS);
}
si = mtod(m, struct spx *);
if (SSEQ_LT(si->si_seq, cb->s_smax))
spxstat.spxs_sndrexmitpack++;
else
spxstat.spxs_sndpack++;
} else if (cb->s_force || cb->s_flags & SF_ACKNOW) {
/*
* Must send an acknowledgement or a probe
*/
if (cb->s_force)
spxstat.spxs_sndprobe++;
if (cb->s_flags & SF_ACKNOW)
spxstat.spxs_sndacks++;
m = m_gethdr(M_DONTWAIT, MT_HEADER);
if (m == NULL)
return (ENOBUFS);
/*
* Fill in mbuf with extended SP header
* and addresses and length put into network format.
*/
MH_ALIGN(m, sizeof(struct spx));
m->m_len = sizeof(*si);
m->m_pkthdr.len = sizeof(*si);
si = mtod(m, struct spx *);
si->si_i = *cb->s_ipx;
si->si_s = cb->s_shdr;
si->si_seq = cb->s_smax + 1;
si->si_len = htons(sizeof(*si));
si->si_cc |= SPX_SP;
} else {
cb->s_outx = 3;
if (so->so_options & SO_DEBUG || traceallspxs)
spx_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
return (0);
}
/*
* Stuff checksum and output datagram.
*/
if ((si->si_cc & SPX_SP) == 0) {
if (cb->s_force != (1 + SPXT_PERSIST) ||
cb->s_timer[SPXT_PERSIST] == 0) {
/*
* If this is a new packet and we are not currently
* timing anything, time this one.
*/
if (SSEQ_LT(cb->s_smax, si->si_seq)) {
cb->s_smax = si->si_seq;
if (cb->s_rtt == 0) {
spxstat.spxs_segstimed++;
cb->s_rtseq = si->si_seq;
cb->s_rtt = 1;
}
}
/*
* Set rexmt timer if not currently set,
* Initial value for retransmit timer is smoothed
* round-trip time + 2 * round-trip time variance.
* Initialize shift counter which is used for backoff
* of retransmit time.
*/
if (cb->s_timer[SPXT_REXMT] == 0 &&
cb->s_snxt != cb->s_rack) {
cb->s_timer[SPXT_REXMT] = cb->s_rxtcur;
if (cb->s_timer[SPXT_PERSIST]) {
cb->s_timer[SPXT_PERSIST] = 0;
cb->s_rxtshift = 0;
}
}
} else if (SSEQ_LT(cb->s_smax, si->si_seq)) {
cb->s_smax = si->si_seq;
}
} else if (cb->s_state < TCPS_ESTABLISHED) {
if (cb->s_rtt == 0)
cb->s_rtt = 1; /* Time initial handshake */
if (cb->s_timer[SPXT_REXMT] == 0)
cb->s_timer[SPXT_REXMT] = cb->s_rxtcur;
}
{
/*
* Do not request acks when we ack their data packets or
* when we do a gratuitous window update.
*/
if (((si->si_cc & SPX_SP) == 0) || cb->s_force)
si->si_cc |= SPX_SA;
si->si_seq = htons(si->si_seq);
si->si_alo = htons(alo);
si->si_ack = htons(cb->s_ack);
if (ipxcksum) {
si->si_sum = ipx_cksum(m, ntohs(si->si_len));
} else
si->si_sum = 0xffff;
cb->s_outx = 4;
if (so->so_options & SO_DEBUG || traceallspxs)
spx_trace(SA_OUTPUT, cb->s_state, cb, si, 0);
if (so->so_options & SO_DONTROUTE)
error = ipx_outputfl(m, NULL, IPX_ROUTETOIF);
else
error = ipx_outputfl(m, &cb->s_ipxpcb->ipxp_route, 0);
}
if (error) {
return (error);
}
spxstat.spxs_sndtotal++;
/*
* Data sent (as far as we can tell).
* If this advertises a larger window than any other segment,
* then remember the size of the advertized window.
* Any pending ACK has now been sent.
*/
cb->s_force = 0;
cb->s_flags &= ~(SF_ACKNOW|SF_DELACK);
if (SSEQ_GT(alo, cb->s_alo))
cb->s_alo = alo;
if (sendalot)
goto again;
cb->s_outx = 5;
return (0);
}
static int spx_do_persist_panics = 0;
static void
spx_setpersist(cb)
register struct spxpcb *cb;
{
register int t = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
IPX_LOCK_ASSERT(cb->s_ipxpcb);
if (cb->s_timer[SPXT_REXMT] && spx_do_persist_panics)
panic("spx_output REXMT");
/*
* Start/restart persistance timer.
*/
SPXT_RANGESET(cb->s_timer[SPXT_PERSIST],
t*spx_backoff[cb->s_rxtshift],
SPXTV_PERSMIN, SPXTV_PERSMAX);
if (cb->s_rxtshift < SPX_MAXRXTSHIFT)
cb->s_rxtshift++;
}
int
spx_ctloutput(so, sopt)
struct socket *so;
struct sockopt *sopt;
{
struct ipxpcb *ipxp = sotoipxpcb(so);
register struct spxpcb *cb;
int mask, error;
short soptval;
u_short usoptval;
int optval;
error = 0;
if (sopt->sopt_level != IPXPROTO_SPX) {
/* This will have to be changed when we do more general
stacking of protocols */
return (ipx_ctloutput(so, sopt));
}
if (ipxp == NULL)
return (EINVAL);
else
cb = ipxtospxpcb(ipxp);
switch (sopt->sopt_dir) {
case SOPT_GET:
switch (sopt->sopt_name) {
case SO_HEADERS_ON_INPUT:
mask = SF_HI;
goto get_flags;
case SO_HEADERS_ON_OUTPUT:
mask = SF_HO;
get_flags:
/* Unlocked read. */
soptval = cb->s_flags & mask;
error = sooptcopyout(sopt, &soptval, sizeof soptval);
break;
case SO_MTU:
/* Unlocked read. */
usoptval = cb->s_mtu;
error = sooptcopyout(sopt, &usoptval, sizeof usoptval);
break;
case SO_LAST_HEADER:
/* Unlocked read. */
error = sooptcopyout(sopt, &cb->s_rhdr,
sizeof cb->s_rhdr);
break;
case SO_DEFAULT_HEADERS:
/* Unlocked read. */
error = sooptcopyout(sopt, &cb->s_shdr,
sizeof cb->s_shdr);
break;
default:
error = ENOPROTOOPT;
}
break;
case SOPT_SET:
switch (sopt->sopt_name) {
/* XXX why are these shorts on get and ints on set?
that doesn't make any sense... */
case SO_HEADERS_ON_INPUT:
mask = SF_HI;
goto set_head;
case SO_HEADERS_ON_OUTPUT:
mask = SF_HO;
set_head:
error = sooptcopyin(sopt, &optval, sizeof optval,
sizeof optval);
if (error)
break;
IPX_LOCK(ipxp);
if (cb->s_flags & SF_PI) {
if (optval)
cb->s_flags |= mask;
else
cb->s_flags &= ~mask;
} else error = EINVAL;
IPX_UNLOCK(ipxp);
break;
case SO_MTU:
error = sooptcopyin(sopt, &usoptval, sizeof usoptval,
sizeof usoptval);
if (error)
break;
/* Unlocked write. */
cb->s_mtu = usoptval;
break;
#ifdef SF_NEWCALL
case SO_NEWCALL:
error = sooptcopyin(sopt, &optval, sizeof optval,
sizeof optval);
if (error)
break;
IPX_LOCK(ipxp);
if (optval) {
cb->s_flags2 |= SF_NEWCALL;
spx_newchecks[5]++;
} else {
cb->s_flags2 &= ~SF_NEWCALL;
spx_newchecks[6]++;
}
IPX_UNLOCK(ipxp);
break;
#endif
case SO_DEFAULT_HEADERS:
{
struct spxhdr sp;
error = sooptcopyin(sopt, &sp, sizeof sp,
sizeof sp);
if (error)
break;
IPX_LOCK(ipxp);
cb->s_dt = sp.spx_dt;
cb->s_cc = sp.spx_cc & SPX_EM;
IPX_UNLOCK(ipxp);
}
break;
default:
error = ENOPROTOOPT;
}
break;
}
return (error);
}
static int
spx_usr_abort(so)
struct socket *so;
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
IPX_LIST_LOCK();
IPX_LOCK(ipxp);
spx_drop(cb, ECONNABORTED);
IPX_LIST_UNLOCK();
return (0);
}
/*
* Accept a connection. Essentially all the work is
* done at higher levels; just return the address
* of the peer, storing through addr.
*/
static int
spx_accept(so, nam)
struct socket *so;
struct sockaddr **nam;
{
struct ipxpcb *ipxp;
struct sockaddr_ipx *sipx, ssipx;
ipxp = sotoipxpcb(so);
sipx = &ssipx;
bzero(sipx, sizeof *sipx);
sipx->sipx_len = sizeof *sipx;
sipx->sipx_family = AF_IPX;
IPX_LOCK(ipxp);
sipx->sipx_addr = ipxp->ipxp_faddr;
IPX_UNLOCK(ipxp);
*nam = sodupsockaddr((struct sockaddr *)sipx, M_WAITOK);
return (0);
}
static int
spx_attach(so, proto, td)
struct socket *so;
int proto;
struct thread *td;
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
struct mbuf *mm;
struct sockbuf *sb;
int error;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
if (ipxp != NULL)
return (EISCONN);
IPX_LIST_LOCK();
error = ipx_pcballoc(so, &ipxpcb_list, td);
if (error)
goto spx_attach_end;
if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
error = soreserve(so, (u_long) 3072, (u_long) 3072);
if (error)
goto spx_attach_end;
}
ipxp = sotoipxpcb(so);
MALLOC(cb, struct spxpcb *, sizeof *cb, M_PCB, M_NOWAIT | M_ZERO);
if (cb == NULL) {
error = ENOBUFS;
goto spx_attach_end;
}
sb = &so->so_snd;
mm = m_getclr(M_DONTWAIT, MT_HEADER);
if (mm == NULL) {
FREE(cb, M_PCB);
error = ENOBUFS;
goto spx_attach_end;
}
cb->s_ipx = mtod(mm, struct ipx *);
cb->s_state = TCPS_LISTEN;
cb->s_smax = -1;
cb->s_swl1 = -1;
cb->s_q.si_next = cb->s_q.si_prev = &cb->s_q;
cb->s_ipxpcb = ipxp;
cb->s_mtu = 576 - sizeof(struct spx);
cb->s_cwnd = sbspace(sb) * CUNIT / cb->s_mtu;
cb->s_ssthresh = cb->s_cwnd;
cb->s_cwmx = sbspace(sb) * CUNIT / (2 * sizeof(struct spx));
/* Above is recomputed when connecting to account
for changed buffering or mtu's */
cb->s_rtt = SPXTV_SRTTBASE;
cb->s_rttvar = SPXTV_SRTTDFLT << 2;
SPXT_RANGESET(cb->s_rxtcur,
((SPXTV_SRTTBASE >> 2) + (SPXTV_SRTTDFLT << 2)) >> 1,
SPXTV_MIN, SPXTV_REXMTMAX);
ipxp->ipxp_pcb = (caddr_t)cb;
spx_attach_end:
IPX_LIST_UNLOCK();
return (error);
}
static int
spx_bind(so, nam, td)
struct socket *so;
struct sockaddr *nam;
struct thread *td;
{
struct ipxpcb *ipxp;
int error;
ipxp = sotoipxpcb(so);
IPX_LIST_LOCK();
IPX_LOCK(ipxp);
error = ipx_pcbbind(ipxp, nam, td);
IPX_UNLOCK(ipxp);
IPX_LIST_UNLOCK();
return (error);
}
/*
* Initiate connection to peer.
* Enter SYN_SENT state, and mark socket as connecting.
* Start keep-alive timer, setup prototype header,
* Send initial system packet requesting connection.
*/
static int
spx_connect(so, nam, td)
struct socket *so;
struct sockaddr *nam;
struct thread *td;
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
int error;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
IPX_LIST_LOCK();
IPX_LOCK(ipxp);
if (ipxp->ipxp_lport == 0) {
error = ipx_pcbbind(ipxp, NULL, td);
if (error)
goto spx_connect_end;
}
error = ipx_pcbconnect(ipxp, nam, td);
if (error)
goto spx_connect_end;
soisconnecting(so);
spxstat.spxs_connattempt++;
cb->s_state = TCPS_SYN_SENT;
cb->s_did = 0;
spx_template(cb);
cb->s_timer[SPXT_KEEP] = SPXTV_KEEP;
cb->s_force = 1 + SPXTV_KEEP;
/*
* Other party is required to respond to
* the port I send from, but he is not
* required to answer from where I am sending to,
* so allow wildcarding.
* original port I am sending to is still saved in
* cb->s_dport.
*/
ipxp->ipxp_fport = 0;
error = spx_output(cb, NULL);
spx_connect_end:
IPX_UNLOCK(ipxp);
IPX_LIST_UNLOCK();
return (error);
}
static int
spx_detach(so)
struct socket *so;
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
if (ipxp == NULL)
return (ENOTCONN);
IPX_LIST_LOCK();
IPX_LOCK(ipxp);
if (cb->s_state > TCPS_LISTEN)
spx_disconnect(cb);
else
spx_close(cb);
IPX_LIST_UNLOCK();
return (0);
}
/*
* We may decide later to implement connection closing
* handshaking at the spx level optionally.
* here is the hook to do it:
*/
static int
spx_usr_disconnect(so)
struct socket *so;
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
IPX_LIST_LOCK();
IPX_LOCK(ipxp);
spx_disconnect(cb);
IPX_LIST_UNLOCK();
return (0);
}
static int
spx_listen(so, td)
struct socket *so;
struct thread *td;
{
int error;
struct ipxpcb *ipxp;
struct spxpcb *cb;
error = 0;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
IPX_LIST_LOCK();
IPX_LOCK(ipxp);
SOCK_LOCK(so);
error = solisten_proto_check(so);
if (error == 0 && ipxp->ipxp_lport == 0)
error = ipx_pcbbind(ipxp, NULL, td);
if (error == 0) {
cb->s_state = TCPS_LISTEN;
solisten_proto(so);
}
SOCK_UNLOCK(so);
IPX_UNLOCK(ipxp);
IPX_LIST_UNLOCK();
return (error);
}
/*
* After a receive, possibly send acknowledgment
* updating allocation.
*/
static int
spx_rcvd(so, flags)
struct socket *so;
int flags;
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
IPX_LOCK(ipxp);
cb->s_flags |= SF_RVD;
spx_output(cb, NULL);
cb->s_flags &= ~SF_RVD;
IPX_UNLOCK(ipxp);
return (0);
}
static int
spx_rcvoob(so, m, flags)
struct socket *so;
struct mbuf *m;
int flags;
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
SOCKBUF_LOCK(&so->so_rcv);
if ((cb->s_oobflags & SF_IOOB) || so->so_oobmark ||
(so->so_rcv.sb_state & SBS_RCVATMARK)) {
SOCKBUF_UNLOCK(&so->so_rcv);
m->m_len = 1;
/* Unlocked read. */
*mtod(m, caddr_t) = cb->s_iobc;
return (0);
}
SOCKBUF_UNLOCK(&so->so_rcv);
return (EINVAL);
}
static int
spx_send(so, flags, m, addr, controlp, td)
struct socket *so;
int flags;
struct mbuf *m;
struct sockaddr *addr;
struct mbuf *controlp;
struct thread *td;
{
int error;
struct ipxpcb *ipxp;
struct spxpcb *cb;
error = 0;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
IPX_LOCK(ipxp);
if (flags & PRUS_OOB) {
if (sbspace(&so->so_snd) < -512) {
error = ENOBUFS;
goto spx_send_end;
}
cb->s_oobflags |= SF_SOOB;
}
if (controlp != NULL) {
u_short *p = mtod(controlp, u_short *);
spx_newchecks[2]++;
if ((p[0] == 5) && (p[1] == 1)) { /* XXXX, for testing */
cb->s_shdr.spx_dt = *(u_char *)(&p[2]);
spx_newchecks[3]++;
}
m_freem(controlp);
}
controlp = NULL;
error = spx_output(cb, m);
m = NULL;
spx_send_end:
IPX_UNLOCK(ipxp);
if (controlp != NULL)
m_freem(controlp);
if (m != NULL)
m_freem(m);
return (error);
}
static int
spx_shutdown(so)
struct socket *so;
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
ipxp = sotoipxpcb(so);
cb = ipxtospxpcb(ipxp);
socantsendmore(so);
IPX_LIST_LOCK();
IPX_LOCK(ipxp);
spx_usrclosed(cb);
IPX_LIST_UNLOCK();
return (0);
}
static int
spx_sp_attach(so, proto, td)
struct socket *so;
int proto;
struct thread *td;
{
int error;
struct ipxpcb *ipxp;
error = spx_attach(so, proto, td);
if (error == 0) {
ipxp = sotoipxpcb(so);
((struct spxpcb *)ipxp->ipxp_pcb)->s_flags |=
(SF_HI | SF_HO | SF_PI);
}
return (error);
}
/*
* Create template to be used to send spx packets on a connection.
* Called after host entry created, fills
* in a skeletal spx header (choosing connection id),
* minimizing the amount of work necessary when the connection is used.
*/
static void
spx_template(cb)
register struct spxpcb *cb;
{
register struct ipxpcb *ipxp = cb->s_ipxpcb;
register struct ipx *ipx = cb->s_ipx;
register struct sockbuf *sb = &(ipxp->ipxp_socket->so_snd);
IPX_LOCK_ASSERT(ipxp);
ipx->ipx_pt = IPXPROTO_SPX;
ipx->ipx_sna = ipxp->ipxp_laddr;
ipx->ipx_dna = ipxp->ipxp_faddr;
cb->s_sid = htons(spx_iss);
spx_iss += SPX_ISSINCR/2;
cb->s_alo = 1;
cb->s_cwnd = (sbspace(sb) * CUNIT) / cb->s_mtu;
cb->s_ssthresh = cb->s_cwnd; /* Try to expand fast to full complement
of large packets */
cb->s_cwmx = (sbspace(sb) * CUNIT) / (2 * sizeof(struct spx));
cb->s_cwmx = max(cb->s_cwmx, cb->s_cwnd);
/* But allow for lots of little packets as well */
}
/*
* Close a SPIP control block:
* discard spx control block itself
* discard ipx protocol control block
* wake up any sleepers
* cb will always be invalid after this call.
*/
void
spx_close(cb)
register struct spxpcb *cb;
{
register struct spx_q *s;
struct ipxpcb *ipxp = cb->s_ipxpcb;
struct socket *so = ipxp->ipxp_socket;
register struct mbuf *m;
IPX_LIST_LOCK_ASSERT();
IPX_LOCK_ASSERT(ipxp);
s = cb->s_q.si_next;
while (s != &(cb->s_q)) {
s = s->si_next;
m = dtom(s->si_prev);
remque(s->si_prev);
m_freem(m);
}
m_free(dtom(cb->s_ipx));
FREE(cb, M_PCB);
ipxp->ipxp_pcb = NULL;
soisdisconnected(so);
ipx_pcbdetach(ipxp);
spxstat.spxs_closed++;
}
/*
* Someday we may do level 3 handshaking
* to close a connection or send a xerox style error.
* For now, just close.
* cb will always be invalid after this call.
*/
static void
spx_usrclosed(cb)
register struct spxpcb *cb;
{
IPX_LIST_LOCK_ASSERT();
IPX_LOCK_ASSERT(cb->s_ipxpcb);
spx_close(cb);
}
/*
* cb will always be invalid after this call.
*/
static void
spx_disconnect(cb)
register struct spxpcb *cb;
{
IPX_LIST_LOCK_ASSERT();
IPX_LOCK_ASSERT(cb->s_ipxpcb);
spx_close(cb);
}
/*
* Drop connection, reporting
* the specified error.
* cb will always be invalid after this call.
*/
static void
spx_drop(cb, errno)
register struct spxpcb *cb;
int errno;
{
struct socket *so = cb->s_ipxpcb->ipxp_socket;
IPX_LIST_LOCK_ASSERT();
IPX_LOCK_ASSERT(cb->s_ipxpcb);
/*
* someday, in the xerox world
* we will generate error protocol packets
* announcing that the socket has gone away.
*/
if (TCPS_HAVERCVDSYN(cb->s_state)) {
spxstat.spxs_drops++;
cb->s_state = TCPS_CLOSED;
/*tcp_output(cb);*/
} else
spxstat.spxs_conndrops++;
so->so_error = errno;
spx_close(cb);
}
/*
* Fast timeout routine for processing delayed acks
*/
void
spx_fasttimo()
{
struct ipxpcb *ipxp;
struct spxpcb *cb;
IPX_LIST_LOCK();
LIST_FOREACH(ipxp, &ipxpcb_list, ipxp_list) {
IPX_LOCK(ipxp);
if ((cb = (struct spxpcb *)ipxp->ipxp_pcb) != NULL &&
(cb->s_flags & SF_DELACK)) {
cb->s_flags &= ~SF_DELACK;
cb->s_flags |= SF_ACKNOW;
spxstat.spxs_delack++;
spx_output(cb, NULL);
}
IPX_UNLOCK(ipxp);
}
IPX_LIST_UNLOCK();
}
/*
* spx protocol timeout routine called every 500 ms.
* Updates the timers in all active pcb's and
* causes finite state machine actions if timers expire.
*/
void
spx_slowtimo()
{
struct ipxpcb *ip, *ip_temp;
struct spxpcb *cb;
int i;
/*
* Search through tcb's and update active timers. Note that timers
* may free the ipxpcb, so be sure to handle that case.
*
* spx_timers() may remove an ipxpcb entry, so we have to be ready to
* continue despite that. The logic here is a bit obfuscated.
*/
IPX_LIST_LOCK();
LIST_FOREACH_SAFE(ip, &ipxpcb_list, ipxp_list, ip_temp) {
cb = ipxtospxpcb(ip);
if (cb == NULL)
continue;
IPX_LOCK(cb->s_ipxpcb);
for (i = 0; i < SPXT_NTIMERS; i++) {
if (cb->s_timer[i] && --cb->s_timer[i] == 0) {
/*
* spx_timers() returns (NULL) if it free'd
* the pcb.
*/
cb = spx_timers(cb, i);
if (cb == NULL)
break;
}
}
if (cb != NULL) {
cb->s_idle++;
if (cb->s_rtt)
cb->s_rtt++;
IPX_UNLOCK(cb->s_ipxpcb);
}
}
spx_iss += SPX_ISSINCR/PR_SLOWHZ; /* increment iss */
IPX_LIST_UNLOCK();
}
/*
* SPX timer processing.
*/
static struct spxpcb *
spx_timers(cb, timer)
register struct spxpcb *cb;
int timer;
{
long rexmt;
int win;
IPX_LIST_LOCK_ASSERT();
IPX_LOCK_ASSERT(cb->s_ipxpcb);
cb->s_force = 1 + timer;
switch (timer) {
/*
* 2 MSL timeout in shutdown went off. TCP deletes connection
* control block.
*/
case SPXT_2MSL:
printf("spx: SPXT_2MSL went off for no reason\n");
cb->s_timer[timer] = 0;
break;
/*
* Retransmission timer went off. Message has not
* been acked within retransmit interval. Back off
* to a longer retransmit interval and retransmit one packet.
*/
case SPXT_REXMT:
if (++cb->s_rxtshift > SPX_MAXRXTSHIFT) {
cb->s_rxtshift = SPX_MAXRXTSHIFT;
spxstat.spxs_timeoutdrop++;
spx_drop(cb, ETIMEDOUT);
cb = NULL;
break;
}
spxstat.spxs_rexmttimeo++;
rexmt = ((cb->s_srtt >> 2) + cb->s_rttvar) >> 1;
rexmt *= spx_backoff[cb->s_rxtshift];
SPXT_RANGESET(cb->s_rxtcur, rexmt, SPXTV_MIN, SPXTV_REXMTMAX);
cb->s_timer[SPXT_REXMT] = cb->s_rxtcur;
/*
* If we have backed off fairly far, our srtt
* estimate is probably bogus. Clobber it
* so we'll take the next rtt measurement as our srtt;
* move the current srtt into rttvar to keep the current
* retransmit times until then.
*/
if (cb->s_rxtshift > SPX_MAXRXTSHIFT / 4 ) {
cb->s_rttvar += (cb->s_srtt >> 2);
cb->s_srtt = 0;
}
cb->s_snxt = cb->s_rack;
/*
* If timing a packet, stop the timer.
*/
cb->s_rtt = 0;
/*
* See very long discussion in tcp_timer.c about congestion
* window and sstrhesh
*/
win = min(cb->s_swnd, (cb->s_cwnd/CUNIT)) / 2;
if (win < 2)
win = 2;
cb->s_cwnd = CUNIT;
cb->s_ssthresh = win * CUNIT;
spx_output(cb, NULL);
break;
/*
* Persistance timer into zero window.
* Force a probe to be sent.
*/
case SPXT_PERSIST:
spxstat.spxs_persisttimeo++;
spx_setpersist(cb);
spx_output(cb, NULL);
break;
/*
* Keep-alive timer went off; send something
* or drop connection if idle for too long.
*/
case SPXT_KEEP:
spxstat.spxs_keeptimeo++;
if (cb->s_state < TCPS_ESTABLISHED)
goto dropit;
if (cb->s_ipxpcb->ipxp_socket->so_options & SO_KEEPALIVE) {
if (cb->s_idle >= SPXTV_MAXIDLE)
goto dropit;
spxstat.spxs_keepprobe++;
spx_output(cb, NULL);
} else
cb->s_idle = 0;
cb->s_timer[SPXT_KEEP] = SPXTV_KEEP;
break;
dropit:
spxstat.spxs_keepdrops++;
spx_drop(cb, ETIMEDOUT);
cb = NULL;
break;
}
return (cb);
}
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