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uipc_socket2.c
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uipc_socket2.c
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/* $OpenBSD: uipc_socket2.c,v 1.155 2024/05/17 19:11:14 mvs Exp $ */
/* $NetBSD: uipc_socket2.c,v 1.11 1996/02/04 02:17:55 christos Exp $ */
/*
* Copyright (c) 1982, 1986, 1988, 1990, 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. 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.
*
* @(#)uipc_socket2.c 8.1 (Berkeley) 6/10/93
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/domain.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/signalvar.h>
#include <sys/pool.h>
/*
* Primitive routines for operating on sockets and socket buffers
*/
u_long sb_max = SB_MAX; /* patchable */
extern struct pool mclpools[];
extern struct pool mbpool;
/*
* Procedures to manipulate state flags of socket
* and do appropriate wakeups. Normal sequence from the
* active (originating) side is that soisconnecting() is
* called during processing of connect() call,
* resulting in an eventual call to soisconnected() if/when the
* connection is established. When the connection is torn down
* soisdisconnecting() is called during processing of disconnect() call,
* and soisdisconnected() is called when the connection to the peer
* is totally severed. The semantics of these routines are such that
* connectionless protocols can call soisconnected() and soisdisconnected()
* only, bypassing the in-progress calls when setting up a ``connection''
* takes no time.
*
* From the passive side, a socket is created with
* two queues of sockets: so_q0 for connections in progress
* and so_q for connections already made and awaiting user acceptance.
* As a protocol is preparing incoming connections, it creates a socket
* structure queued on so_q0 by calling sonewconn(). When the connection
* is established, soisconnected() is called, and transfers the
* socket structure to so_q, making it available to accept().
*
* If a socket is closed with sockets on either
* so_q0 or so_q, these sockets are dropped.
*
* If higher level protocols are implemented in
* the kernel, the wakeups done here will sometimes
* cause software-interrupt process scheduling.
*/
void
soisconnecting(struct socket *so)
{
soassertlocked(so);
so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
so->so_state |= SS_ISCONNECTING;
}
void
soisconnected(struct socket *so)
{
struct socket *head = so->so_head;
soassertlocked(so);
so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING);
so->so_state |= SS_ISCONNECTED;
if (head != NULL && so->so_onq == &head->so_q0) {
int persocket = solock_persocket(so);
if (persocket) {
soref(so);
soref(head);
sounlock(so);
solock(head);
solock(so);
if (so->so_onq != &head->so_q0) {
sounlock(head);
sorele(head);
sorele(so);
return;
}
sorele(head);
sorele(so);
}
soqremque(so, 0);
soqinsque(head, so, 1);
sorwakeup(head);
wakeup_one(&head->so_timeo);
if (persocket)
sounlock(head);
} else {
wakeup(&so->so_timeo);
sorwakeup(so);
sowwakeup(so);
}
}
void
soisdisconnecting(struct socket *so)
{
soassertlocked(so);
so->so_state &= ~SS_ISCONNECTING;
so->so_state |= SS_ISDISCONNECTING;
mtx_enter(&so->so_rcv.sb_mtx);
so->so_rcv.sb_state |= SS_CANTRCVMORE;
mtx_leave(&so->so_rcv.sb_mtx);
mtx_enter(&so->so_snd.sb_mtx);
so->so_snd.sb_state |= SS_CANTSENDMORE;
mtx_leave(&so->so_snd.sb_mtx);
wakeup(&so->so_timeo);
sowwakeup(so);
sorwakeup(so);
}
void
soisdisconnected(struct socket *so)
{
soassertlocked(so);
so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
so->so_state |= SS_ISDISCONNECTED;
mtx_enter(&so->so_rcv.sb_mtx);
so->so_rcv.sb_state |= SS_CANTRCVMORE;
mtx_leave(&so->so_rcv.sb_mtx);
mtx_enter(&so->so_snd.sb_mtx);
so->so_snd.sb_state |= SS_CANTSENDMORE;
mtx_leave(&so->so_snd.sb_mtx);
wakeup(&so->so_timeo);
sowwakeup(so);
sorwakeup(so);
}
/*
* When an attempt at a new connection is noted on a socket
* which accepts connections, sonewconn is called. If the
* connection is possible (subject to space constraints, etc.)
* then we allocate a new structure, properly linked into the
* data structure of the original socket, and return this.
* Connstatus may be 0 or SS_ISCONNECTED.
*/
struct socket *
sonewconn(struct socket *head, int connstatus, int wait)
{
struct socket *so;
int persocket = solock_persocket(head);
int soqueue = connstatus ? 1 : 0;
/*
* XXXSMP as long as `so' and `head' share the same lock, we
* can call soreserve() and pr_attach() below w/o explicitly
* locking `so'.
*/
soassertlocked(head);
if (m_pool_used() > 95)
return (NULL);
if (head->so_qlen + head->so_q0len > head->so_qlimit * 3)
return (NULL);
so = soalloc(head->so_proto, wait);
if (so == NULL)
return (NULL);
so->so_type = head->so_type;
so->so_options = head->so_options &~ SO_ACCEPTCONN;
so->so_linger = head->so_linger;
so->so_state = head->so_state | SS_NOFDREF;
so->so_proto = head->so_proto;
so->so_timeo = head->so_timeo;
so->so_euid = head->so_euid;
so->so_ruid = head->so_ruid;
so->so_egid = head->so_egid;
so->so_rgid = head->so_rgid;
so->so_cpid = head->so_cpid;
/*
* Lock order will be `head' -> `so' while these sockets are linked.
*/
if (persocket)
solock(so);
/*
* Inherit watermarks but those may get clamped in low mem situations.
*/
if (soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat))
goto fail;
mtx_enter(&head->so_snd.sb_mtx);
so->so_snd.sb_wat = head->so_snd.sb_wat;
so->so_snd.sb_lowat = head->so_snd.sb_lowat;
so->so_snd.sb_timeo_nsecs = head->so_snd.sb_timeo_nsecs;
mtx_leave(&head->so_snd.sb_mtx);
mtx_enter(&head->so_rcv.sb_mtx);
so->so_rcv.sb_wat = head->so_rcv.sb_wat;
so->so_rcv.sb_lowat = head->so_rcv.sb_lowat;
so->so_rcv.sb_timeo_nsecs = head->so_rcv.sb_timeo_nsecs;
mtx_leave(&head->so_rcv.sb_mtx);
sigio_copy(&so->so_sigio, &head->so_sigio);
soqinsque(head, so, soqueue);
if (pru_attach(so, 0, wait) != 0) {
soqremque(so, soqueue);
goto fail;
}
if (connstatus) {
so->so_state |= connstatus;
sorwakeup(head);
wakeup(&head->so_timeo);
}
if (persocket)
sounlock(so);
return (so);
fail:
if (persocket)
sounlock(so);
sigio_free(&so->so_sigio);
klist_free(&so->so_rcv.sb_klist);
klist_free(&so->so_snd.sb_klist);
pool_put(&socket_pool, so);
return (NULL);
}
void
soqinsque(struct socket *head, struct socket *so, int q)
{
soassertlocked(head);
soassertlocked(so);
KASSERT(so->so_onq == NULL);
so->so_head = head;
if (q == 0) {
head->so_q0len++;
so->so_onq = &head->so_q0;
} else {
head->so_qlen++;
so->so_onq = &head->so_q;
}
TAILQ_INSERT_TAIL(so->so_onq, so, so_qe);
}
int
soqremque(struct socket *so, int q)
{
struct socket *head = so->so_head;
soassertlocked(so);
soassertlocked(head);
if (q == 0) {
if (so->so_onq != &head->so_q0)
return (0);
head->so_q0len--;
} else {
if (so->so_onq != &head->so_q)
return (0);
head->so_qlen--;
}
TAILQ_REMOVE(so->so_onq, so, so_qe);
so->so_onq = NULL;
so->so_head = NULL;
return (1);
}
/*
* Socantsendmore indicates that no more data will be sent on the
* socket; it would normally be applied to a socket when the user
* informs the system that no more data is to be sent, by the protocol
* code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data
* will be received, and will normally be applied to the socket by a
* protocol when it detects that the peer will send no more data.
* Data queued for reading in the socket may yet be read.
*/
void
socantsendmore(struct socket *so)
{
soassertlocked(so);
mtx_enter(&so->so_snd.sb_mtx);
so->so_snd.sb_state |= SS_CANTSENDMORE;
mtx_leave(&so->so_snd.sb_mtx);
sowwakeup(so);
}
void
socantrcvmore(struct socket *so)
{
if ((so->so_rcv.sb_flags & SB_MTXLOCK) == 0)
soassertlocked(so);
mtx_enter(&so->so_rcv.sb_mtx);
so->so_rcv.sb_state |= SS_CANTRCVMORE;
mtx_leave(&so->so_rcv.sb_mtx);
sorwakeup(so);
}
void
solock(struct socket *so)
{
switch (so->so_proto->pr_domain->dom_family) {
case PF_INET:
case PF_INET6:
NET_LOCK();
break;
default:
rw_enter_write(&so->so_lock);
break;
}
}
void
solock_shared(struct socket *so)
{
switch (so->so_proto->pr_domain->dom_family) {
case PF_INET:
case PF_INET6:
if (so->so_proto->pr_usrreqs->pru_lock != NULL) {
NET_LOCK_SHARED();
rw_enter_write(&so->so_lock);
} else
NET_LOCK();
break;
default:
rw_enter_write(&so->so_lock);
break;
}
}
int
solock_persocket(struct socket *so)
{
switch (so->so_proto->pr_domain->dom_family) {
case PF_INET:
case PF_INET6:
return 0;
default:
return 1;
}
}
void
solock_pair(struct socket *so1, struct socket *so2)
{
KASSERT(so1 != so2);
KASSERT(so1->so_type == so2->so_type);
KASSERT(solock_persocket(so1));
if (so1 < so2) {
solock(so1);
solock(so2);
} else {
solock(so2);
solock(so1);
}
}
void
sounlock(struct socket *so)
{
switch (so->so_proto->pr_domain->dom_family) {
case PF_INET:
case PF_INET6:
NET_UNLOCK();
break;
default:
rw_exit_write(&so->so_lock);
break;
}
}
void
sounlock_shared(struct socket *so)
{
switch (so->so_proto->pr_domain->dom_family) {
case PF_INET:
case PF_INET6:
if (so->so_proto->pr_usrreqs->pru_unlock != NULL) {
rw_exit_write(&so->so_lock);
NET_UNLOCK_SHARED();
} else
NET_UNLOCK();
break;
default:
rw_exit_write(&so->so_lock);
break;
}
}
void
soassertlocked_readonly(struct socket *so)
{
switch (so->so_proto->pr_domain->dom_family) {
case PF_INET:
case PF_INET6:
NET_ASSERT_LOCKED();
break;
default:
rw_assert_wrlock(&so->so_lock);
break;
}
}
void
soassertlocked(struct socket *so)
{
switch (so->so_proto->pr_domain->dom_family) {
case PF_INET:
case PF_INET6:
if (rw_status(&netlock) == RW_READ) {
NET_ASSERT_LOCKED();
if (splassert_ctl > 0 && pru_locked(so) == 0 &&
rw_status(&so->so_lock) != RW_WRITE)
splassert_fail(0, RW_WRITE, __func__);
} else
NET_ASSERT_LOCKED_EXCLUSIVE();
break;
default:
rw_assert_wrlock(&so->so_lock);
break;
}
}
int
sosleep_nsec(struct socket *so, void *ident, int prio, const char *wmesg,
uint64_t nsecs)
{
int ret;
switch (so->so_proto->pr_domain->dom_family) {
case PF_INET:
case PF_INET6:
if (so->so_proto->pr_usrreqs->pru_unlock != NULL &&
rw_status(&netlock) == RW_READ) {
rw_exit_write(&so->so_lock);
}
ret = rwsleep_nsec(ident, &netlock, prio, wmesg, nsecs);
if (so->so_proto->pr_usrreqs->pru_lock != NULL &&
rw_status(&netlock) == RW_READ) {
rw_enter_write(&so->so_lock);
}
break;
default:
ret = rwsleep_nsec(ident, &so->so_lock, prio, wmesg, nsecs);
break;
}
return ret;
}
void
sbmtxassertlocked(struct socket *so, struct sockbuf *sb)
{
if (sb->sb_flags & SB_MTXLOCK) {
if (splassert_ctl > 0 && mtx_owned(&sb->sb_mtx) == 0)
splassert_fail(0, RW_WRITE, __func__);
} else
soassertlocked(so);
}
/*
* Wait for data to arrive at/drain from a socket buffer.
*/
int
sbwait(struct socket *so, struct sockbuf *sb)
{
uint64_t timeo_nsecs;
int prio = (sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH;
if (sb->sb_flags & SB_MTXLOCK) {
MUTEX_ASSERT_LOCKED(&sb->sb_mtx);
sb->sb_flags |= SB_WAIT;
return msleep_nsec(&sb->sb_cc, &sb->sb_mtx, prio, "sbwait",
sb->sb_timeo_nsecs);
}
soassertlocked(so);
mtx_enter(&sb->sb_mtx);
timeo_nsecs = sb->sb_timeo_nsecs;
sb->sb_flags |= SB_WAIT;
mtx_leave(&sb->sb_mtx);
return sosleep_nsec(so, &sb->sb_cc, prio, "netio", timeo_nsecs);
}
int
sblock(struct sockbuf *sb, int flags)
{
int rwflags = RW_WRITE, error;
if (!(flags & SBL_NOINTR || sb->sb_flags & SB_NOINTR))
rwflags |= RW_INTR;
if (!(flags & SBL_WAIT))
rwflags |= RW_NOSLEEP;
error = rw_enter(&sb->sb_lock, rwflags);
if (error == EBUSY)
error = EWOULDBLOCK;
return error;
}
void
sbunlock(struct sockbuf *sb)
{
rw_exit(&sb->sb_lock);
}
/*
* Wakeup processes waiting on a socket buffer.
* Do asynchronous notification via SIGIO
* if the socket buffer has the SB_ASYNC flag set.
*/
void
sowakeup(struct socket *so, struct sockbuf *sb)
{
int dowakeup = 0, dopgsigio = 0;
mtx_enter(&sb->sb_mtx);
if (sb->sb_flags & SB_WAIT) {
sb->sb_flags &= ~SB_WAIT;
dowakeup = 1;
}
if (sb->sb_flags & SB_ASYNC)
dopgsigio = 1;
knote_locked(&sb->sb_klist, 0);
mtx_leave(&sb->sb_mtx);
if (dowakeup)
wakeup(&sb->sb_cc);
if (dopgsigio)
pgsigio(&so->so_sigio, SIGIO, 0);
}
/*
* Socket buffer (struct sockbuf) utility routines.
*
* Each socket contains two socket buffers: one for sending data and
* one for receiving data. Each buffer contains a queue of mbufs,
* information about the number of mbufs and amount of data in the
* queue, and other fields allowing select() statements and notification
* on data availability to be implemented.
*
* Data stored in a socket buffer is maintained as a list of records.
* Each record is a list of mbufs chained together with the m_next
* field. Records are chained together with the m_nextpkt field. The upper
* level routine soreceive() expects the following conventions to be
* observed when placing information in the receive buffer:
*
* 1. If the protocol requires each message be preceded by the sender's
* name, then a record containing that name must be present before
* any associated data (mbuf's must be of type MT_SONAME).
* 2. If the protocol supports the exchange of ``access rights'' (really
* just additional data associated with the message), and there are
* ``rights'' to be received, then a record containing this data
* should be present (mbuf's must be of type MT_CONTROL).
* 3. If a name or rights record exists, then it must be followed by
* a data record, perhaps of zero length.
*
* Before using a new socket structure it is first necessary to reserve
* buffer space to the socket, by calling sbreserve(). This should commit
* some of the available buffer space in the system buffer pool for the
* socket (currently, it does nothing but enforce limits). The space
* should be released by calling sbrelease() when the socket is destroyed.
*/
int
soreserve(struct socket *so, u_long sndcc, u_long rcvcc)
{
soassertlocked(so);
mtx_enter(&so->so_rcv.sb_mtx);
mtx_enter(&so->so_snd.sb_mtx);
if (sbreserve(so, &so->so_snd, sndcc))
goto bad;
so->so_snd.sb_wat = sndcc;
if (so->so_snd.sb_lowat == 0)
so->so_snd.sb_lowat = MCLBYTES;
if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
if (sbreserve(so, &so->so_rcv, rcvcc))
goto bad2;
so->so_rcv.sb_wat = rcvcc;
if (so->so_rcv.sb_lowat == 0)
so->so_rcv.sb_lowat = 1;
mtx_leave(&so->so_snd.sb_mtx);
mtx_leave(&so->so_rcv.sb_mtx);
return (0);
bad2:
sbrelease(so, &so->so_snd);
bad:
mtx_leave(&so->so_snd.sb_mtx);
mtx_leave(&so->so_rcv.sb_mtx);
return (ENOBUFS);
}
/*
* Allot mbufs to a sockbuf.
* Attempt to scale mbmax so that mbcnt doesn't become limiting
* if buffering efficiency is near the normal case.
*/
int
sbreserve(struct socket *so, struct sockbuf *sb, u_long cc)
{
sbmtxassertlocked(so, sb);
if (cc == 0 || cc > sb_max)
return (1);
sb->sb_hiwat = cc;
sb->sb_mbmax = max(3 * MAXMCLBYTES, cc * 8);
if (sb->sb_lowat > sb->sb_hiwat)
sb->sb_lowat = sb->sb_hiwat;
return (0);
}
/*
* In low memory situation, do not accept any greater than normal request.
*/
int
sbcheckreserve(u_long cnt, u_long defcnt)
{
if (cnt > defcnt && sbchecklowmem())
return (ENOBUFS);
return (0);
}
int
sbchecklowmem(void)
{
static int sblowmem;
unsigned int used = m_pool_used();
if (used < 60)
sblowmem = 0;
else if (used > 80)
sblowmem = 1;
return (sblowmem);
}
/*
* Free mbufs held by a socket, and reserved mbuf space.
*/
void
sbrelease(struct socket *so, struct sockbuf *sb)
{
sbflush(so, sb);
sb->sb_hiwat = sb->sb_mbmax = 0;
}
/*
* Routines to add and remove
* data from an mbuf queue.
*
* The routines sbappend() or sbappendrecord() are normally called to
* append new mbufs to a socket buffer, after checking that adequate
* space is available, comparing the function sbspace() with the amount
* of data to be added. sbappendrecord() differs from sbappend() in
* that data supplied is treated as the beginning of a new record.
* To place a sender's address, optional access rights, and data in a
* socket receive buffer, sbappendaddr() should be used. To place
* access rights and data in a socket receive buffer, sbappendrights()
* should be used. In either case, the new data begins a new record.
* Note that unlike sbappend() and sbappendrecord(), these routines check
* for the caller that there will be enough space to store the data.
* Each fails if there is not enough space, or if it cannot find mbufs
* to store additional information in.
*
* Reliable protocols may use the socket send buffer to hold data
* awaiting acknowledgement. Data is normally copied from a socket
* send buffer in a protocol with m_copym for output to a peer,
* and then removing the data from the socket buffer with sbdrop()
* or sbdroprecord() when the data is acknowledged by the peer.
*/
#ifdef SOCKBUF_DEBUG
void
sblastrecordchk(struct sockbuf *sb, const char *where)
{
struct mbuf *m = sb->sb_mb;
while (m && m->m_nextpkt)
m = m->m_nextpkt;
if (m != sb->sb_lastrecord) {
printf("sblastrecordchk: sb_mb %p sb_lastrecord %p last %p\n",
sb->sb_mb, sb->sb_lastrecord, m);
printf("packet chain:\n");
for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt)
printf("\t%p\n", m);
panic("sblastrecordchk from %s", where);
}
}
void
sblastmbufchk(struct sockbuf *sb, const char *where)
{
struct mbuf *m = sb->sb_mb;
struct mbuf *n;
while (m && m->m_nextpkt)
m = m->m_nextpkt;
while (m && m->m_next)
m = m->m_next;
if (m != sb->sb_mbtail) {
printf("sblastmbufchk: sb_mb %p sb_mbtail %p last %p\n",
sb->sb_mb, sb->sb_mbtail, m);
printf("packet tree:\n");
for (m = sb->sb_mb; m != NULL; m = m->m_nextpkt) {
printf("\t");
for (n = m; n != NULL; n = n->m_next)
printf("%p ", n);
printf("\n");
}
panic("sblastmbufchk from %s", where);
}
}
#endif /* SOCKBUF_DEBUG */
#define SBLINKRECORD(sb, m0) \
do { \
if ((sb)->sb_lastrecord != NULL) \
(sb)->sb_lastrecord->m_nextpkt = (m0); \
else \
(sb)->sb_mb = (m0); \
(sb)->sb_lastrecord = (m0); \
} while (/*CONSTCOND*/0)
/*
* Append mbuf chain m to the last record in the
* socket buffer sb. The additional space associated
* the mbuf chain is recorded in sb. Empty mbufs are
* discarded and mbufs are compacted where possible.
*/
void
sbappend(struct socket *so, struct sockbuf *sb, struct mbuf *m)
{
struct mbuf *n;
if (m == NULL)
return;
sbmtxassertlocked(so, sb);
SBLASTRECORDCHK(sb, "sbappend 1");
if ((n = sb->sb_lastrecord) != NULL) {
/*
* XXX Would like to simply use sb_mbtail here, but
* XXX I need to verify that I won't miss an EOR that
* XXX way.
*/
do {
if (n->m_flags & M_EOR) {
sbappendrecord(so, sb, m); /* XXXXXX!!!! */
return;
}
} while (n->m_next && (n = n->m_next));
} else {
/*
* If this is the first record in the socket buffer, it's
* also the last record.
*/
sb->sb_lastrecord = m;
}
sbcompress(so, sb, m, n);
SBLASTRECORDCHK(sb, "sbappend 2");
}
/*
* This version of sbappend() should only be used when the caller
* absolutely knows that there will never be more than one record
* in the socket buffer, that is, a stream protocol (such as TCP).
*/
void
sbappendstream(struct socket *so, struct sockbuf *sb, struct mbuf *m)
{
KASSERT(sb == &so->so_rcv || sb == &so->so_snd);
soassertlocked(so);
KDASSERT(m->m_nextpkt == NULL);
KASSERT(sb->sb_mb == sb->sb_lastrecord);
SBLASTMBUFCHK(sb, __func__);
sbcompress(so, sb, m, sb->sb_mbtail);
sb->sb_lastrecord = sb->sb_mb;
SBLASTRECORDCHK(sb, __func__);
}
#ifdef SOCKBUF_DEBUG
void
sbcheck(struct socket *so, struct sockbuf *sb)
{
struct mbuf *m, *n;
u_long len = 0, mbcnt = 0;
for (m = sb->sb_mb; m; m = m->m_nextpkt) {
for (n = m; n; n = n->m_next) {
len += n->m_len;
mbcnt += MSIZE;
if (n->m_flags & M_EXT)
mbcnt += n->m_ext.ext_size;
if (m != n && n->m_nextpkt)
panic("sbcheck nextpkt");
}
}
if (len != sb->sb_cc || mbcnt != sb->sb_mbcnt) {
printf("cc %lu != %lu || mbcnt %lu != %lu\n", len, sb->sb_cc,
mbcnt, sb->sb_mbcnt);
panic("sbcheck");
}
}
#endif
/*
* As above, except the mbuf chain
* begins a new record.
*/
void
sbappendrecord(struct socket *so, struct sockbuf *sb, struct mbuf *m0)
{
struct mbuf *m;
sbmtxassertlocked(so, sb);
if (m0 == NULL)
return;
/*
* Put the first mbuf on the queue.
* Note this permits zero length records.
*/
sballoc(so, sb, m0);
SBLASTRECORDCHK(sb, "sbappendrecord 1");
SBLINKRECORD(sb, m0);
m = m0->m_next;
m0->m_next = NULL;
if (m && (m0->m_flags & M_EOR)) {
m0->m_flags &= ~M_EOR;
m->m_flags |= M_EOR;
}
sbcompress(so, sb, m, m0);
SBLASTRECORDCHK(sb, "sbappendrecord 2");
}
/*
* Append address and data, and optionally, control (ancillary) data
* to the receive queue of a socket. If present,
* m0 must include a packet header with total length.
* Returns 0 if no space in sockbuf or insufficient mbufs.
*/
int
sbappendaddr(struct socket *so, struct sockbuf *sb, const struct sockaddr *asa,
struct mbuf *m0, struct mbuf *control)
{
struct mbuf *m, *n, *nlast;
int space = asa->sa_len;
sbmtxassertlocked(so, sb);
if (m0 && (m0->m_flags & M_PKTHDR) == 0)
panic("sbappendaddr");
if (m0)
space += m0->m_pkthdr.len;
for (n = control; n; n = n->m_next) {
space += n->m_len;
if (n->m_next == NULL) /* keep pointer to last control buf */
break;
}
if (space > sbspace(so, sb))
return (0);
if (asa->sa_len > MLEN)
return (0);
MGET(m, M_DONTWAIT, MT_SONAME);
if (m == NULL)
return (0);
m->m_len = asa->sa_len;
memcpy(mtod(m, caddr_t), asa, asa->sa_len);
if (n)
n->m_next = m0; /* concatenate data to control */
else
control = m0;
m->m_next = control;
SBLASTRECORDCHK(sb, "sbappendaddr 1");
for (n = m; n->m_next != NULL; n = n->m_next)
sballoc(so, sb, n);
sballoc(so, sb, n);
nlast = n;
SBLINKRECORD(sb, m);
sb->sb_mbtail = nlast;
SBLASTMBUFCHK(sb, "sbappendaddr");
SBLASTRECORDCHK(sb, "sbappendaddr 2");
return (1);
}
int
sbappendcontrol(struct socket *so, struct sockbuf *sb, struct mbuf *m0,
struct mbuf *control)
{
struct mbuf *m, *mlast, *n;
int eor = 0, space = 0;
sbmtxassertlocked(so, sb);
if (control == NULL)
panic("sbappendcontrol");
for (m = control; ; m = m->m_next) {
space += m->m_len;
if (m->m_next == NULL)
break;
}
n = m; /* save pointer to last control buffer */
for (m = m0; m; m = m->m_next) {
space += m->m_len;
eor |= m->m_flags & M_EOR;
if (eor) {
if (m->m_next == NULL)
m->m_flags |= M_EOR;
else
m->m_flags &= ~M_EOR;
}
}
if (space > sbspace(so, sb))
return (0);
n->m_next = m0; /* concatenate data to control */
SBLASTRECORDCHK(sb, "sbappendcontrol 1");
for (m = control; m->m_next != NULL; m = m->m_next)
sballoc(so, sb, m);
sballoc(so, sb, m);
mlast = m;
SBLINKRECORD(sb, control);
sb->sb_mbtail = mlast;
SBLASTMBUFCHK(sb, "sbappendcontrol");