File: [cvs.NetBSD.org] / src / sys / kern / uipc_socket2.c (download)
Revision 1.88, Tue Jan 29 12:39:39 2008 UTC (16 years, 2 months ago) by yamt
Branch: MAIN
Changes since 1.87: +3 -3
lines
sbreserve: curlwp can't be NULL these days.
XXX these code seems to need an overhaul.
|
/* $NetBSD: uipc_socket2.c,v 1.88 2008/01/29 12:39:39 yamt 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 8.2 (Berkeley) 2/14/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uipc_socket2.c,v 1.88 2008/01/29 12:39:39 yamt Exp $");
#include "opt_mbuftrace.h"
#include "opt_sb_max.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/buf.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/poll.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/signalvar.h>
#include <sys/kauth.h>
/*
* Primitive routines for operating on sockets and socket buffers
*/
/* strings for sleep message: */
const char netcon[] = "netcon";
const char netcls[] = "netcls";
const char netio[] = "netio";
const char netlck[] = "netlck";
u_long sb_max = SB_MAX; /* maximum socket buffer size */
static u_long sb_max_adj; /* adjusted sb_max */
/*
* 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)
{
so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING);
so->so_state |= SS_ISCONNECTING;
}
void
soisconnected(struct socket *so)
{
struct socket *head;
head = so->so_head;
so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING|SS_ISCONFIRMING);
so->so_state |= SS_ISCONNECTED;
if (head && soqremque(so, 0)) {
soqinsque(head, so, 1);
sorwakeup(head);
wakeup((void *)&head->so_timeo);
} else {
wakeup((void *)&so->so_timeo);
sorwakeup(so);
sowwakeup(so);
}
}
void
soisdisconnecting(struct socket *so)
{
so->so_state &= ~SS_ISCONNECTING;
so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE);
wakeup((void *)&so->so_timeo);
sowwakeup(so);
sorwakeup(so);
}
void
soisdisconnected(struct socket *so)
{
so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING);
so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE|SS_ISDISCONNECTED);
wakeup((void *)&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, propoerly linked into the
* data structure of the original socket, and return this.
* Connstatus may be 0, SS_ISCONFIRMING, or SS_ISCONNECTED.
*/
struct socket *
sonewconn(struct socket *head, int connstatus)
{
struct socket *so;
int soqueue;
soqueue = connstatus ? 1 : 0;
if (head->so_qlen + head->so_q0len > 3 * head->so_qlimit / 2)
return ((struct socket *)0);
so = pool_get(&socket_pool, PR_NOWAIT);
if (so == NULL)
return (NULL);
memset((void *)so, 0, sizeof(*so));
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_pgid = head->so_pgid;
so->so_send = head->so_send;
so->so_receive = head->so_receive;
so->so_uidinfo = head->so_uidinfo;
#ifdef MBUFTRACE
so->so_mowner = head->so_mowner;
so->so_rcv.sb_mowner = head->so_rcv.sb_mowner;
so->so_snd.sb_mowner = head->so_snd.sb_mowner;
#endif
selinit(&so->so_rcv.sb_sel);
selinit(&so->so_snd.sb_sel);
(void) soreserve(so, head->so_snd.sb_hiwat, head->so_rcv.sb_hiwat);
so->so_snd.sb_lowat = head->so_snd.sb_lowat;
so->so_rcv.sb_lowat = head->so_rcv.sb_lowat;
so->so_rcv.sb_timeo = head->so_rcv.sb_timeo;
so->so_snd.sb_timeo = head->so_snd.sb_timeo;
so->so_rcv.sb_flags |= head->so_rcv.sb_flags & SB_AUTOSIZE;
so->so_snd.sb_flags |= head->so_snd.sb_flags & SB_AUTOSIZE;
soqinsque(head, so, soqueue);
if ((*so->so_proto->pr_usrreq)(so, PRU_ATTACH,
(struct mbuf *)0, (struct mbuf *)0, (struct mbuf *)0,
(struct lwp *)0)) {
(void) soqremque(so, soqueue);
seldestroy(&so->so_rcv.sb_sel);
seldestroy(&so->so_snd.sb_sel);
pool_put(&socket_pool, so);
return (NULL);
}
if (connstatus) {
sorwakeup(head);
wakeup((void *)&head->so_timeo);
so->so_state |= connstatus;
}
return (so);
}
void
soqinsque(struct socket *head, struct socket *so, int q)
{
#ifdef DIAGNOSTIC
if (so->so_onq != NULL)
panic("soqinsque");
#endif
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;
head = so->so_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)
{
so->so_state |= SS_CANTSENDMORE;
sowwakeup(so);
}
void
socantrcvmore(struct socket *so)
{
so->so_state |= SS_CANTRCVMORE;
sorwakeup(so);
}
/*
* Wait for data to arrive at/drain from a socket buffer.
*/
int
sbwait(struct sockbuf *sb)
{
sb->sb_flags |= SB_WAIT;
return (tsleep((void *)&sb->sb_cc,
(sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK | PCATCH, netio,
sb->sb_timeo));
}
/*
* Lock a sockbuf already known to be locked;
* return any error returned from sleep (EINTR).
*/
int
sb_lock(struct sockbuf *sb)
{
int error;
while (sb->sb_flags & SB_LOCK) {
sb->sb_flags |= SB_WANT;
error = tsleep((void *)&sb->sb_flags,
(sb->sb_flags & SB_NOINTR) ? PSOCK : PSOCK|PCATCH,
netlck, 0);
if (error)
return (error);
}
sb->sb_flags |= SB_LOCK;
return (0);
}
/*
* 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 code)
{
selnotify(&sb->sb_sel, 0);
sb->sb_flags &= ~SB_SEL;
if (sb->sb_flags & SB_WAIT) {
sb->sb_flags &= ~SB_WAIT;
wakeup((void *)&sb->sb_cc);
}
if (sb->sb_flags & SB_ASYNC) {
int band;
if (code == POLL_IN)
band = POLLIN|POLLRDNORM;
else
band = POLLOUT|POLLWRNORM;
fownsignal(so->so_pgid, SIGIO, code, band, so);
}
if (sb->sb_flags & SB_UPCALL)
(*so->so_upcall)(so, so->so_upcallarg, M_DONTWAIT);
}
/*
* 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 poll() 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
sb_max_set(u_long new_sbmax)
{
int s;
if (new_sbmax < (16 * 1024))
return (EINVAL);
s = splsoftnet();
sb_max = new_sbmax;
sb_max_adj = (u_quad_t)new_sbmax * MCLBYTES / (MSIZE + MCLBYTES);
splx(s);
return (0);
}
int
soreserve(struct socket *so, u_long sndcc, u_long rcvcc)
{
/*
* there's at least one application (a configure script of screen)
* which expects a fifo is writable even if it has "some" bytes
* in its buffer.
* so we want to make sure (hiwat - lowat) >= (some bytes).
*
* PIPE_BUF here is an arbitrary value chosen as (some bytes) above.
* we expect it's large enough for such applications.
*/
u_long lowat = MAX(sock_loan_thresh, MCLBYTES);
u_long hiwat = lowat + PIPE_BUF;
if (sndcc < hiwat)
sndcc = hiwat;
if (sbreserve(&so->so_snd, sndcc, so) == 0)
goto bad;
if (sbreserve(&so->so_rcv, rcvcc, so) == 0)
goto bad2;
if (so->so_rcv.sb_lowat == 0)
so->so_rcv.sb_lowat = 1;
if (so->so_snd.sb_lowat == 0)
so->so_snd.sb_lowat = lowat;
if (so->so_snd.sb_lowat > so->so_snd.sb_hiwat)
so->so_snd.sb_lowat = so->so_snd.sb_hiwat;
return (0);
bad2:
sbrelease(&so->so_snd, so);
bad:
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 sockbuf *sb, u_long cc, struct socket *so)
{
struct lwp *l = curlwp; /* XXX */
rlim_t maxcc;
struct uidinfo *uidinfo;
KDASSERT(sb_max_adj != 0);
if (cc == 0 || cc > sb_max_adj)
return (0);
if (so) {
if (kauth_cred_geteuid(l->l_cred) == so->so_uidinfo->ui_uid)
maxcc = l->l_proc->p_rlimit[RLIMIT_SBSIZE].rlim_cur;
else
maxcc = RLIM_INFINITY;
uidinfo = so->so_uidinfo;
} else {
uidinfo = uid_find(0); /* XXX: nothing better */
maxcc = RLIM_INFINITY;
}
if (!chgsbsize(uidinfo, &sb->sb_hiwat, cc, maxcc))
return 0;
sb->sb_mbmax = min(cc * 2, sb_max);
if (sb->sb_lowat > sb->sb_hiwat)
sb->sb_lowat = sb->sb_hiwat;
return (1);
}
/*
* Free mbufs held by a socket, and reserved mbuf space.
*/
void
sbrelease(struct sockbuf *sb, struct socket *so)
{
sbflush(sb);
(void)chgsbsize(so->so_uidinfo, &sb->sb_hiwat, 0, RLIM_INFINITY);
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_copy 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 */
/*
* Link a chain of records onto a socket buffer
*/
#define SBLINKRECORDCHAIN(sb, m0, mlast) \
do { \
if ((sb)->sb_lastrecord != NULL) \
(sb)->sb_lastrecord->m_nextpkt = (m0); \
else \
(sb)->sb_mb = (m0); \
(sb)->sb_lastrecord = (mlast); \
} while (/*CONSTCOND*/0)
#define SBLINKRECORD(sb, m0) \
SBLINKRECORDCHAIN(sb, m0, m0)
/*
* 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 sockbuf *sb, struct mbuf *m)
{
struct mbuf *n;
if (m == 0)
return;
#ifdef MBUFTRACE
m_claimm(m, sb->sb_mowner);
#endif
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(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(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 sockbuf *sb, struct mbuf *m)
{
KDASSERT(m->m_nextpkt == NULL);
KASSERT(sb->sb_mb == sb->sb_lastrecord);
SBLASTMBUFCHK(sb, __func__);
#ifdef MBUFTRACE
m_claimm(m, sb->sb_mowner);
#endif
sbcompress(sb, m, sb->sb_mbtail);
sb->sb_lastrecord = sb->sb_mb;
SBLASTRECORDCHK(sb, __func__);
}
#ifdef SOCKBUF_DEBUG
void
sbcheck(struct sockbuf *sb)
{
struct mbuf *m;
u_long len, mbcnt;
len = 0;
mbcnt = 0;
for (m = sb->sb_mb; m; m = m->m_next) {
len += m->m_len;
mbcnt += MSIZE;
if (m->m_flags & M_EXT)
mbcnt += m->m_ext.ext_size;
if (m->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 sockbuf *sb, struct mbuf *m0)
{
struct mbuf *m;
if (m0 == 0)
return;
#ifdef MBUFTRACE
m_claimm(m0, sb->sb_mowner);
#endif
/*
* Put the first mbuf on the queue.
* Note this permits zero length records.
*/
sballoc(sb, m0);
SBLASTRECORDCHK(sb, "sbappendrecord 1");
SBLINKRECORD(sb, m0);
m = m0->m_next;
m0->m_next = 0;
if (m && (m0->m_flags & M_EOR)) {
m0->m_flags &= ~M_EOR;
m->m_flags |= M_EOR;
}
sbcompress(sb, m, m0);
SBLASTRECORDCHK(sb, "sbappendrecord 2");
}
/*
* As above except that OOB data
* is inserted at the beginning of the sockbuf,
* but after any other OOB data.
*/
void
sbinsertoob(struct sockbuf *sb, struct mbuf *m0)
{
struct mbuf *m, **mp;
if (m0 == 0)
return;
SBLASTRECORDCHK(sb, "sbinsertoob 1");
for (mp = &sb->sb_mb; (m = *mp) != NULL; mp = &((*mp)->m_nextpkt)) {
again:
switch (m->m_type) {
case MT_OOBDATA:
continue; /* WANT next train */
case MT_CONTROL:
if ((m = m->m_next) != NULL)
goto again; /* inspect THIS train further */
}
break;
}
/*
* Put the first mbuf on the queue.
* Note this permits zero length records.
*/
sballoc(sb, m0);
m0->m_nextpkt = *mp;
if (*mp == NULL) {
/* m0 is actually the new tail */
sb->sb_lastrecord = m0;
}
*mp = m0;
m = m0->m_next;
m0->m_next = 0;
if (m && (m0->m_flags & M_EOR)) {
m0->m_flags &= ~M_EOR;
m->m_flags |= M_EOR;
}
sbcompress(sb, m, m0);
SBLASTRECORDCHK(sb, "sbinsertoob 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 sockbuf *sb, const struct sockaddr *asa, struct mbuf *m0,
struct mbuf *control)
{
struct mbuf *m, *n, *nlast;
int space, len;
space = asa->sa_len;
if (m0 != NULL) {
if ((m0->m_flags & M_PKTHDR) == 0)
panic("sbappendaddr");
space += m0->m_pkthdr.len;
#ifdef MBUFTRACE
m_claimm(m0, sb->sb_mowner);
#endif
}
for (n = control; n; n = n->m_next) {
space += n->m_len;
MCLAIM(n, sb->sb_mowner);
if (n->m_next == 0) /* keep pointer to last control buf */
break;
}
if (space > sbspace(sb))
return (0);
MGET(m, M_DONTWAIT, MT_SONAME);
if (m == 0)
return (0);
MCLAIM(m, sb->sb_mowner);
/*
* XXX avoid 'comparison always true' warning which isn't easily
* avoided.
*/
len = asa->sa_len;
if (len > MLEN) {
MEXTMALLOC(m, asa->sa_len, M_NOWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_free(m);
return (0);
}
}
m->m_len = asa->sa_len;
memcpy(mtod(m, void *), 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(sb, n);
sballoc(sb, n);
nlast = n;
SBLINKRECORD(sb, m);
sb->sb_mbtail = nlast;
SBLASTMBUFCHK(sb, "sbappendaddr");
SBLASTRECORDCHK(sb, "sbappendaddr 2");
return (1);
}
/*
* Helper for sbappendchainaddr: prepend a struct sockaddr* to
* an mbuf chain.
*/
static inline struct mbuf *
m_prepend_sockaddr(struct sockbuf *sb, struct mbuf *m0,
const struct sockaddr *asa)
{
struct mbuf *m;
const int salen = asa->sa_len;
/* only the first in each chain need be a pkthdr */
MGETHDR(m, M_DONTWAIT, MT_SONAME);
if (m == 0)
return (0);
MCLAIM(m, sb->sb_mowner);
#ifdef notyet
if (salen > MHLEN) {
MEXTMALLOC(m, salen, M_NOWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_free(m);
return (0);
}
}
#else
KASSERT(salen <= MHLEN);
#endif
m->m_len = salen;
memcpy(mtod(m, void *), asa, salen);
m->m_next = m0;
m->m_pkthdr.len = salen + m0->m_pkthdr.len;
return m;
}
int
sbappendaddrchain(struct sockbuf *sb, const struct sockaddr *asa,
struct mbuf *m0, int sbprio)
{
int space;
struct mbuf *m, *n, *n0, *nlast;
int error;
/*
* XXX sbprio reserved for encoding priority of this* request:
* SB_PRIO_NONE --> honour normal sb limits
* SB_PRIO_ONESHOT_OVERFLOW --> if socket has any space,
* take whole chain. Intended for large requests
* that should be delivered atomically (all, or none).
* SB_PRIO_OVERDRAFT -- allow a small (2*MLEN) overflow
* over normal socket limits, for messages indicating
* buffer overflow in earlier normal/lower-priority messages
* SB_PRIO_BESTEFFORT --> ignore limits entirely.
* Intended for kernel-generated messages only.
* Up to generator to avoid total mbuf resource exhaustion.
*/
(void)sbprio;
if (m0 && (m0->m_flags & M_PKTHDR) == 0)
panic("sbappendaddrchain");
space = sbspace(sb);
#ifdef notyet
/*
* Enforce SB_PRIO_* limits as described above.
*/
#endif
n0 = NULL;
nlast = NULL;
for (m = m0; m; m = m->m_nextpkt) {
struct mbuf *np;
#ifdef MBUFTRACE
m_claimm(m, sb->sb_mowner);
#endif
/* Prepend sockaddr to this record (m) of input chain m0 */
n = m_prepend_sockaddr(sb, m, asa);
if (n == NULL) {
error = ENOBUFS;
goto bad;
}
/* Append record (asa+m) to end of new chain n0 */
if (n0 == NULL) {
n0 = n;
} else {
nlast->m_nextpkt = n;
}
/* Keep track of last record on new chain */
nlast = n;
for (np = n; np; np = np->m_next)
sballoc(sb, np);
}
SBLASTRECORDCHK(sb, "sbappendaddrchain 1");
/* Drop the entire chain of (asa+m) records onto the socket */
SBLINKRECORDCHAIN(sb, n0, nlast);
SBLASTRECORDCHK(sb, "sbappendaddrchain 2");
for (m = nlast; m->m_next; m = m->m_next)
;
sb->sb_mbtail = m;
SBLASTMBUFCHK(sb, "sbappendaddrchain");
return (1);
bad:
/*
* On error, free the prepended addreseses. For consistency
* with sbappendaddr(), leave it to our caller to free
* the input record chain passed to us as m0.
*/
while ((n = n0) != NULL) {
struct mbuf *np;
/* Undo the sballoc() of this record */
for (np = n; np; np = np->m_next)
sbfree(sb, np);
n0 = n->m_nextpkt; /* iterate at next prepended address */
MFREE(n, np); /* free prepended address (not data) */
}
return 0;
}
int
sbappendcontrol(struct sockbuf *sb, struct mbuf *m0, struct mbuf *control)
{
struct mbuf *m, *mlast, *n;
int space;
space = 0;
if (control == 0)
panic("sbappendcontrol");
for (m = control; ; m = m->m_next) {
space += m->m_len;
MCLAIM(m, sb->sb_mowner);
if (m->m_next == 0)
break;
}
n = m; /* save pointer to last control buffer */
for (m = m0; m; m = m->m_next) {
MCLAIM(m, sb->sb_mowner);
space += m->m_len;
}
if (space > sbspace(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(sb, m);
sballoc(sb, m);
mlast = m;
SBLINKRECORD(sb, control);
sb->sb_mbtail = mlast;
SBLASTMBUFCHK(sb, "sbappendcontrol");
SBLASTRECORDCHK(sb, "sbappendcontrol 2");
return (1);
}
/*
* Compress mbuf chain m into the socket
* buffer sb following mbuf n. If n
* is null, the buffer is presumed empty.
*/
void
sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n)
{
int eor;
struct mbuf *o;
eor = 0;
while (m) {
eor |= m->m_flags & M_EOR;
if (m->m_len == 0 &&
(eor == 0 ||
(((o = m->m_next) || (o = n)) &&
o->m_type == m->m_type))) {
if (sb->sb_lastrecord == m)
sb->sb_lastrecord = m->m_next;
m = m_free(m);
continue;
}
if (n && (n->m_flags & M_EOR) == 0 &&
/* M_TRAILINGSPACE() checks buffer writeability */
m->m_len <= MCLBYTES / 4 && /* XXX Don't copy too much */
m->m_len <= M_TRAILINGSPACE(n) &&
n->m_type == m->m_type) {
memcpy(mtod(n, char *) + n->m_len, mtod(m, void *),
(unsigned)m->m_len);
n->m_len += m->m_len;
sb->sb_cc += m->m_len;
m = m_free(m);
continue;
}
if (n)
n->m_next = m;
else
sb->sb_mb = m;
sb->sb_mbtail = m;
sballoc(sb, m);
n = m;
m->m_flags &= ~M_EOR;
m = m->m_next;
n->m_next = 0;
}
if (eor) {
if (n)
n->m_flags |= eor;
else
printf("semi-panic: sbcompress\n");
}
SBLASTMBUFCHK(sb, __func__);
}
/*
* Free all mbufs in a sockbuf.
* Check that all resources are reclaimed.
*/
void
sbflush(struct sockbuf *sb)
{
KASSERT((sb->sb_flags & SB_LOCK) == 0);
while (sb->sb_mbcnt)
sbdrop(sb, (int)sb->sb_cc);
KASSERT(sb->sb_cc == 0);
KASSERT(sb->sb_mb == NULL);
KASSERT(sb->sb_mbtail == NULL);
KASSERT(sb->sb_lastrecord == NULL);
}
/*
* Drop data from (the front of) a sockbuf.
*/
void
sbdrop(struct sockbuf *sb, int len)
{
struct mbuf *m, *mn, *next;
next = (m = sb->sb_mb) ? m->m_nextpkt : 0;
while (len > 0) {
if (m == 0) {
if (next == 0)
panic("sbdrop");
m = next;
next = m->m_nextpkt;
continue;
}
if (m->m_len > len) {
m->m_len -= len;
m->m_data += len;
sb->sb_cc -= len;
break;
}
len -= m->m_len;
sbfree(sb, m);
MFREE(m, mn);
m = mn;
}
while (m && m->m_len == 0) {
sbfree(sb, m);
MFREE(m, mn);
m = mn;
}
if (m) {
sb->sb_mb = m;
m->m_nextpkt = next;
} else
sb->sb_mb = next;
/*
* First part is an inline SB_EMPTY_FIXUP(). Second part
* makes sure sb_lastrecord is up-to-date if we dropped
* part of the last record.
*/
m = sb->sb_mb;
if (m == NULL) {
sb->sb_mbtail = NULL;
sb->sb_lastrecord = NULL;
} else if (m->m_nextpkt == NULL)
sb->sb_lastrecord = m;
}
/*
* Drop a record off the front of a sockbuf
* and move the next record to the front.
*/
void
sbdroprecord(struct sockbuf *sb)
{
struct mbuf *m, *mn;
m = sb->sb_mb;
if (m) {
sb->sb_mb = m->m_nextpkt;
do {
sbfree(sb, m);
MFREE(m, mn);
} while ((m = mn) != NULL);
}
SB_EMPTY_FIXUP(sb);
}
/*
* Create a "control" mbuf containing the specified data
* with the specified type for presentation on a socket buffer.
*/
struct mbuf *
sbcreatecontrol(void *p, int size, int type, int level)
{
struct cmsghdr *cp;
struct mbuf *m;
if (CMSG_SPACE(size) > MCLBYTES) {
printf("sbcreatecontrol: message too large %d\n", size);
return NULL;
}
if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL)
return ((struct mbuf *) NULL);
if (CMSG_SPACE(size) > MLEN) {
MCLGET(m, M_DONTWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_free(m);
return NULL;
}
}
cp = mtod(m, struct cmsghdr *);
memcpy(CMSG_DATA(cp), p, size);
m->m_len = CMSG_SPACE(size);
cp->cmsg_len = CMSG_LEN(size);
cp->cmsg_level = level;
cp->cmsg_type = type;
return (m);
}
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