xnu-201.14.tar.gz

[apple/xnu.git] / bsd / kern / uipc_socket.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1998, 1999 Apple Computer, Inc. All Rights Reserved */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * 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. 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.
 *
 *      @(#)uipc_socket.c       8.6 (Berkeley) 5/2/95
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/fcntl.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/kernel.h>
#include <sys/poll.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/ev.h>
#include <sys/kdebug.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <kern/zalloc.h>
#include <machine/limits.h>

int                     so_cache_hw = 0;
int                     so_cache_timeouts = 0;
int                     so_cache_max_freed = 0;
int                     cached_sock_count = 0;
struct socket           *socket_cache_head = 0;
struct socket           *socket_cache_tail = 0;
u_long                  so_cache_time = 0;
int                     so_cache_init_done = 0;
struct zone             *so_cache_zone;
extern int              get_inpcb_str_size();
extern int              get_tcp_str_size();

#include <machine/limits.h>

int socket_debug = 0;
int socket_zone = M_SOCKET;
so_gen_t        so_gencnt;      /* generation count for sockets */

MALLOC_DEFINE(M_SONAME, "soname", "socket name");
MALLOC_DEFINE(M_PCB, "pcb", "protocol control block");

#define DBG_LAYER_IN_BEG        NETDBG_CODE(DBG_NETSOCK, 0)
#define DBG_LAYER_IN_END        NETDBG_CODE(DBG_NETSOCK, 2)
#define DBG_LAYER_OUT_BEG       NETDBG_CODE(DBG_NETSOCK, 1)
#define DBG_LAYER_OUT_END       NETDBG_CODE(DBG_NETSOCK, 3)
#define DBG_FNC_SOSEND          NETDBG_CODE(DBG_NETSOCK, (4 << 8) | 1)
#define DBG_FNC_SORECEIVE       NETDBG_CODE(DBG_NETSOCK, (8 << 8))
#define DBG_FNC_SOSHUTDOWN      NETDBG_CODE(DBG_NETSOCK, (9 << 8))


SYSCTL_DECL(_kern_ipc);

static int somaxconn = SOMAXCONN;
SYSCTL_INT(_kern_ipc, KIPC_SOMAXCONN, somaxconn, CTLFLAG_RW, &somaxconn,
           0, "");

/* Should we get a maximum also ??? */
static int sosendminchain = 16384;
SYSCTL_INT(_kern_ipc, OID_AUTO, sosendminchain, CTLFLAG_RW, &sosendminchain,
           0, "");

void  so_cache_timer();

/*
 * Socket operation routines.
 * These routines are called by the routines in
 * sys_socket.c or from a system process, and
 * implement the semantics of socket operations by
 * switching out to the protocol specific routines.
 */

void socketinit()
{
    vm_size_t   str_size;

    so_cache_init_done = 1;

    timeout(so_cache_timer, NULL, (SO_CACHE_FLUSH_INTERVAL * hz));
    str_size = (vm_size_t)( sizeof(struct socket) + 4 +
                            get_inpcb_str_size()  + 4 +
                            get_tcp_str_size());
    so_cache_zone = zinit (str_size, 120000*str_size, 8192, "socache zone");
#if TEMPDEBUG
    kprintf("cached_sock_alloc -- so_cache_zone size is %x\n", str_size);
#endif

}

void   cached_sock_alloc(so, waitok)
struct socket **so;
int           waitok;

{
    caddr_t     temp;
    int         s;
    register u_long  offset;


    s = splnet(); 
    if (cached_sock_count) {
            cached_sock_count--;
            *so = socket_cache_head;
            if (*so == 0)
                    panic("cached_sock_alloc: cached sock is null");

            socket_cache_head = socket_cache_head->cache_next;
            if (socket_cache_head)
                    socket_cache_head->cache_prev = 0;
            else
                    socket_cache_tail = 0;
            splx(s); 

            temp = (*so)->so_saved_pcb;
            bzero((caddr_t)*so, sizeof(struct socket));
#if TEMPDEBUG
            kprintf("cached_sock_alloc - retreiving cached sock %x - count == %d\n", *so,
                   cached_sock_count);
#endif
            (*so)->so_saved_pcb = temp;
    }
    else {
#if TEMPDEBUG
            kprintf("Allocating cached sock %x from memory\n", *so);
#endif

            splx(s); 
            if (waitok)
                 *so = (struct socket *) zalloc(so_cache_zone);
            else
                 *so = (struct socket *) zalloc_noblock(so_cache_zone);

            if (*so == 0)
                 return;

            bzero((caddr_t)*so, sizeof(struct socket));

            /*
             * Define offsets for extra structures into our single block of
             * memory. Align extra structures on longword boundaries.
             */


            offset = (u_long) *so;
            offset += sizeof(struct socket);
            if (offset & 0x3) {
                offset += 4;
                offset &= 0xfffffffc;
            }
            (*so)->so_saved_pcb = (caddr_t) offset;
            offset += get_inpcb_str_size();
            if (offset & 0x3) {
                offset += 4;
                offset &= 0xfffffffc;
            }

            ((struct inpcb *) (*so)->so_saved_pcb)->inp_saved_ppcb = (caddr_t) offset;
#if TEMPDEBUG
            kprintf("Allocating cached socket - %x, pcb=%x tcpcb=%x\n", *so,
                    (*so)->so_saved_pcb,
                    ((struct inpcb *)(*so)->so_saved_pcb)->inp_saved_ppcb);
#endif
    }

    (*so)->cached_in_sock_layer = 1;
}


void cached_sock_free(so) 
struct socket *so;
{
        int   s;


        s = splnet(); 
        if (++cached_sock_count > MAX_CACHED_SOCKETS) {
                --cached_sock_count;
                splx(s); 
#if TEMPDEBUG
                kprintf("Freeing overflowed cached socket %x\n", so);
#endif
                zfree(so_cache_zone, (vm_offset_t) so);
        }
        else {
#if TEMPDEBUG
                kprintf("Freeing socket %x into cache\n", so);
#endif
                if (so_cache_hw < cached_sock_count)
                        so_cache_hw = cached_sock_count;

                so->cache_next = socket_cache_head;
                so->cache_prev = 0;
                if (socket_cache_head)
                        socket_cache_head->cache_prev = so;
                else
                        socket_cache_tail = so;

                so->cache_timestamp = so_cache_time;
                socket_cache_head = so;
                splx(s); 
        }

#if TEMPDEBUG
        kprintf("Freed cached sock %x into cache - count is %d\n", so, cached_sock_count);
#endif


}


void so_cache_timer()
{
        register struct socket  *p;
        register int            s;
        register int            n_freed = 0;
        boolean_t       funnel_state;

        funnel_state = thread_funnel_set(network_flock, TRUE);

        ++so_cache_time;

        s = splnet();

        while (p = socket_cache_tail)
        {
                if ((so_cache_time - p->cache_timestamp) < SO_CACHE_TIME_LIMIT)
                        break;

                so_cache_timeouts++;
                
                if (socket_cache_tail = p->cache_prev)
                        p->cache_prev->cache_next = 0;
                if (--cached_sock_count == 0)
                        socket_cache_head = 0;

                splx(s);

                zfree(so_cache_zone, (vm_offset_t) p);
                
                splnet();
                if (++n_freed >= SO_CACHE_MAX_FREE_BATCH)
                {
                        so_cache_max_freed++;
                        break;
                }
        }
        splx(s);

        timeout(so_cache_timer, NULL, (SO_CACHE_FLUSH_INTERVAL * hz));

        (void) thread_funnel_set(network_flock, FALSE);

}


/*
 * Get a socket structure from our zone, and initialize it.
 * We don't implement `waitok' yet (see comments in uipc_domain.c).
 * Note that it would probably be better to allocate socket
 * and PCB at the same time, but I'm not convinced that all
 * the protocols can be easily modified to do this.
 */
struct socket *
soalloc(waitok, dom, type)
        int waitok;
        int dom;
        int type;
{
        struct socket *so;

        if ((dom == PF_INET) && (type == SOCK_STREAM)) 
            cached_sock_alloc(&so, waitok);
        else
        {
             so = _MALLOC_ZONE(sizeof(*so), socket_zone, M_WAITOK);
             if (so) 
                  bzero(so, sizeof *so);
        }
        /* XXX race condition for reentrant kernel */

        if (so) {
             so->so_gencnt = ++so_gencnt;
             so->so_zone = socket_zone;
        }

        return so;
}

int
socreate(dom, aso, type, proto)
        int dom;
        struct socket **aso;
        register int type;
        int proto;

{
        struct proc *p = current_proc();
        register struct protosw *prp;
        struct socket *so;
        register int error = 0;

        if (proto)
                prp = pffindproto(dom, proto, type);
        else
                prp = pffindtype(dom, type);
        if (prp == 0 || prp->pr_usrreqs->pru_attach == 0)
                return (EPROTONOSUPPORT);
        if (prp->pr_type != type)
                return (EPROTOTYPE);
        so = soalloc(p != 0, dom, type);
        if (so == 0)
                return (ENOBUFS);

        TAILQ_INIT(&so->so_incomp);
        TAILQ_INIT(&so->so_comp);
        so->so_type = type;

        if (p != 0) {
                if (p->p_ucred->cr_uid == 0)
                        so->so_state = SS_PRIV;

                so->so_uid = p->p_ucred->cr_uid;
        }

        so->so_proto = prp;
        so->so_rcv.sb_flags |= SB_RECV; /* XXX */
        if (prp->pr_sfilter.tqh_first)
                error = sfilter_init(so);
        if (error == 0)
                error = (*prp->pr_usrreqs->pru_attach)(so, proto, p);

        if (error) {
                so->so_state |= SS_NOFDREF;
                sofree(so);
                return (error);
        }
        prp->pr_domain->dom_refs++;
        so->so_rcv.sb_so = so->so_snd.sb_so = so;
        TAILQ_INIT(&so->so_evlist);
        *aso = so;
        return (0);
}

int
sobind(so, nam)
        struct socket *so;
        struct sockaddr *nam;

{
        struct proc *p = current_proc();
        int error;
        struct kextcb *kp;
        int s = splnet();

        error = (*so->so_proto->pr_usrreqs->pru_bind)(so, nam, p);
        if (error == 0)         /* ??? */
        {       kp = sotokextcb(so);
                while (kp)
                {       if (kp->e_soif && kp->e_soif->sf_sobind)
                        {       error = (*kp->e_soif->sf_sobind)(so, nam, kp);
                                if (error)
                                {       if (error == EJUSTRETURN)
                                                break;
                                        splx(s);
                                        return(error);
                                }
                        }
                        kp = kp->e_next;
                }
        }
        splx(s);
        return (error);
}

void
sodealloc(so)
        struct socket *so;
{
        so->so_gencnt = ++so_gencnt;

        if (so->cached_in_sock_layer == 1) 
             cached_sock_free(so);
        else
             _FREE_ZONE(so, sizeof(*so), so->so_zone);
}

int
solisten(so, backlog)
        register struct socket *so;
        int backlog;

{
        struct kextcb *kp;
        struct proc *p = current_proc();
        int s, error;

        s = splnet();
        error = (*so->so_proto->pr_usrreqs->pru_listen)(so, p);
        if (error) {
                splx(s);
                return (error);
        }
        if (TAILQ_EMPTY(&so->so_comp))
                so->so_options |= SO_ACCEPTCONN;
        if (backlog < 0 || backlog > somaxconn)
                backlog = somaxconn;
        so->so_qlimit = backlog;
        kp = sotokextcb(so);
        while (kp)
        {       
                if (kp->e_soif && kp->e_soif->sf_solisten)
                {       error = (*kp->e_soif->sf_solisten)(so, kp);
                        if (error)
                        {       if (error == EJUSTRETURN)
                                        break;
                                splx(s);
                                return(error);
                        }
                }
                kp = kp->e_next;
        }

        splx(s);
        return (0);
}


void
sofree(so)
        register struct socket *so;
{       int error;
        struct kextcb *kp;
        struct socket *head = so->so_head;

        kp = sotokextcb(so);
        while (kp)
        {       if (kp->e_soif && kp->e_soif->sf_sofree)
                {       error = (*kp->e_soif->sf_sofree)(so, kp);
                        if (error) {
                                selthreadclear(&so->so_snd.sb_sel);
                                selthreadclear(&so->so_rcv.sb_sel);
                                return; /* void fn */
                        }
                }
                kp = kp->e_next;
        }

        if (so->so_pcb || (so->so_state & SS_NOFDREF) == 0) {
                selthreadclear(&so->so_snd.sb_sel);
                selthreadclear(&so->so_rcv.sb_sel);
                return;
        }
        if (head != NULL) {
                if (so->so_state & SS_INCOMP) {  
                        TAILQ_REMOVE(&head->so_incomp, so, so_list);
                        head->so_incqlen--;
                } else if (so->so_state & SS_COMP) {
                        /*
                         * We must not decommission a socket that's   
                         * on the accept(2) queue.  If we do, then
                         * accept(2) may hang after select(2) indicated
                         * that the listening socket was ready.
                         */
                                                selthreadclear(&so->so_snd.sb_sel);
                                                selthreadclear(&so->so_rcv.sb_sel);
                        return;
                } else {
                        panic("sofree: not queued");
                }
                head->so_qlen--;
                so->so_state &= ~(SS_INCOMP|SS_COMP);
                so->so_head = NULL;
        }

        selthreadclear(&so->so_snd.sb_sel);
        sbrelease(&so->so_snd);
        sorflush(so);
        sfilter_term(so);
        sodealloc(so);
}

/*
 * Close a socket on last file table reference removal.
 * Initiate disconnect if connected.
 * Free socket when disconnect complete.
 */
int
soclose(so)
        register struct socket *so;
{
        int s = splnet();               /* conservative */
        int error = 0;
        struct kextcb *kp;

#if FB31SIG
        funsetown(so->so_pgid);
#endif
        kp = sotokextcb(so);
        while (kp)
        {       if (kp->e_soif && kp->e_soif->sf_soclose)
                {       error = (*kp->e_soif->sf_soclose)(so, kp);
                        if (error)
                        {       splx(s);
                                return((error == EJUSTRETURN) ? 0 : error);
                        }
                }
                kp = kp->e_next;
        }

        if (so->so_options & SO_ACCEPTCONN) {
                struct socket *sp, *sonext;

                sp = TAILQ_FIRST(&so->so_incomp);
                for (; sp != NULL; sp = sonext) {
                        sonext = TAILQ_NEXT(sp, so_list);
                        (void) soabort(sp);
                }
                for (sp = TAILQ_FIRST(&so->so_comp); sp != NULL; sp = sonext) {
                        sonext = TAILQ_NEXT(sp, so_list);
                        /* Dequeue from so_comp since sofree() won't do it */
                        TAILQ_REMOVE(&so->so_comp, sp, so_list);
                        so->so_qlen--;
                        sp->so_state &= ~SS_COMP;
                        sp->so_head = NULL;
                        (void) soabort(sp);
                }

        }
        if (so->so_pcb == 0)
                goto discard;
        if (so->so_state & SS_ISCONNECTED) {
                if ((so->so_state & SS_ISDISCONNECTING) == 0) {
                        error = sodisconnect(so);
                        if (error)
                                goto drop;
                }
                if (so->so_options & SO_LINGER) {
                        if ((so->so_state & SS_ISDISCONNECTING) &&
                            (so->so_state & SS_NBIO))
                                goto drop;
                        while (so->so_state & SS_ISCONNECTED) {
                                error = tsleep((caddr_t)&so->so_timeo,
                                    PSOCK | PCATCH, "soclos", so->so_linger);
                                if (error)
                                        break;
                        }
                }
        }
drop:
        if (so->so_pcb) {
                int error2 = (*so->so_proto->pr_usrreqs->pru_detach)(so);
                if (error == 0)
                        error = error2;
        }
discard:
        if (so->so_pcb && so->so_state & SS_NOFDREF)
                panic("soclose: NOFDREF");
        so->so_state |= SS_NOFDREF;
        so->so_proto->pr_domain->dom_refs--;
        evsofree(so);
        sofree(so);
        splx(s);
        return (error);
}

/*
 * Must be called at splnet...
 */
int
soabort(so)
        struct socket *so;
{

        return (*so->so_proto->pr_usrreqs->pru_abort)(so);
}

int
soaccept(so, nam)
        register struct socket *so;
        struct sockaddr **nam;
{       int s = splnet();
        int error;
        struct kextcb *kp;

        if ((so->so_state & SS_NOFDREF) == 0)
                panic("soaccept: !NOFDREF");
        so->so_state &= ~SS_NOFDREF;
        error = (*so->so_proto->pr_usrreqs->pru_accept)(so, nam);
        if (error == 0)
        {       kp = sotokextcb(so);
                while (kp) {
                        if (kp->e_soif && kp->e_soif->sf_soaccept)
                        {       error = (*kp->e_soif->sf_soaccept)(so, nam, kp);
                                if (error)
                                {       if (error == EJUSTRETURN)
                                                break;
                                        splx(s);
                                        return(error);
                                }
                        }
                        kp = kp->e_next;
                }
        }
    
    
        splx(s);
        return (error);
}

int
soconnect(so, nam)
        register struct socket *so;
        struct sockaddr *nam;

{
        int s;
        int error;
        struct proc *p = current_proc();
        struct kextcb *kp;

        if (so->so_options & SO_ACCEPTCONN)
                return (EOPNOTSUPP);
        s = splnet();
        /*
         * If protocol is connection-based, can only connect once.
         * Otherwise, if connected, try to disconnect first.
         * This allows user to disconnect by connecting to, e.g.,
         * a null address.
         */
        if (so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING) &&
            ((so->so_proto->pr_flags & PR_CONNREQUIRED) ||
            (error = sodisconnect(so))))
                error = EISCONN;
        else {
                error = (*so->so_proto->pr_usrreqs->pru_connect)(so, nam, p);
                if (error == 0)
                {       
                        kp = sotokextcb(so);
                        while (kp)
                        {       
                                if (kp->e_soif && kp->e_soif->sf_soconnect)
                                {       error = (*kp->e_soif->sf_soconnect)(so, nam, kp);
                                        if (error)
                                        {       if (error == EJUSTRETURN)
                                                        break;
                                                splx(s);
                                                return(error);
                                        }
                                }
                                kp = kp->e_next;
                        }
                }
        }

        splx(s);
        return (error);
}

int
soconnect2(so1, so2)
        register struct socket *so1;
        struct socket *so2;
{
        int s = splnet();
        int error;
        struct kextcb *kp;

        error = (*so1->so_proto->pr_usrreqs->pru_connect2)(so1, so2);
        if (error == 0)
        {       kp = sotokextcb(so1);
                while (kp)
                {       if (kp->e_soif && kp->e_soif->sf_soconnect2)
                        {       error = (*kp->e_soif->sf_soconnect2)(so1, so2, kp);
                                if (error)
                                {       if (error == EJUSTRETURN)
                                                break;
                                        splx(s);
                                        return(error);
                                }
                        }
                        kp = kp->e_next;
                }
        }
        splx(s);
        return (error);
}

int
sodisconnect(so)
        register struct socket *so;
{
        int s = splnet();
        int error;
        struct kextcb *kp;

        if ((so->so_state & SS_ISCONNECTED) == 0) {
                error = ENOTCONN;
                goto bad;
        }
        if (so->so_state & SS_ISDISCONNECTING) {
                error = EALREADY;
                goto bad;
        }
        error = (*so->so_proto->pr_usrreqs->pru_disconnect)(so);

        if (error == 0)
        {       kp = sotokextcb(so);
                while (kp)
                {       if (kp->e_soif && kp->e_soif->sf_sodisconnect)
                        {       error = (*kp->e_soif->sf_sodisconnect)(so, kp);
                                if (error)
                                {       if (error == EJUSTRETURN)
                                                break;
                                        splx(s);
                                        return(error);
                                }
                        }
                        kp = kp->e_next;
                }
        }

bad:
        splx(s);
        return (error);
}

#define SBLOCKWAIT(f)   (((f) & MSG_DONTWAIT) ? M_DONTWAIT : M_WAIT)
/*
 * Send on a socket.
 * If send must go all at once and message is larger than
 * send buffering, then hard error.
 * Lock against other senders.
 * If must go all at once and not enough room now, then
 * inform user that this would block and do nothing.
 * Otherwise, if nonblocking, send as much as possible.
 * The data to be sent is described by "uio" if nonzero,
 * otherwise by the mbuf chain "top" (which must be null
 * if uio is not).  Data provided in mbuf chain must be small
 * enough to send all at once.
 *
 * Returns nonzero on error, timeout or signal; callers
 * must check for short counts if EINTR/ERESTART are returned.
 * Data and control buffers are freed on return.
 * Experiment:
 * MSG_HOLD: go thru most of sosend(), but just enqueue the mbuf
 * MSG_SEND: go thru as for MSG_HOLD on current fragment, then
 *  point at the mbuf chain being constructed and go from there.
 */
int
sosend(so, addr, uio, top, control, flags)
        register struct socket *so;
        struct sockaddr *addr;
        struct uio *uio;
        struct mbuf *top;
        struct mbuf *control;
        int flags;

{
        struct mbuf **mp;
        register struct mbuf *m;
        register long space, len, resid;
        int clen = 0, error, s, dontroute, mlen, sendflags;
        int atomic = sosendallatonce(so) || top;
        struct proc *p = current_proc();
        struct kextcb *kp;

        if (uio)
                resid = uio->uio_resid;
        else
                resid = top->m_pkthdr.len;

        KERNEL_DEBUG((DBG_FNC_SOSEND | DBG_FUNC_START),
                     so,
                     resid,
                     so->so_snd.sb_cc,
                     so->so_snd.sb_lowat,
                     so->so_snd.sb_hiwat);

        /*
         * In theory resid should be unsigned.
         * However, space must be signed, as it might be less than 0
         * if we over-committed, and we must use a signed comparison
         * of space and resid.  On the other hand, a negative resid
         * causes us to loop sending 0-length segments to the protocol.
         *
         * Also check to make sure that MSG_EOR isn't used on SOCK_STREAM
         * type sockets since that's an error.
         */
        if (resid < 0 || so->so_type == SOCK_STREAM && (flags & MSG_EOR)) {
                error = EINVAL;
                goto out;
        }

        dontroute =
            (flags & MSG_DONTROUTE) && (so->so_options & SO_DONTROUTE) == 0 &&
            (so->so_proto->pr_flags & PR_ATOMIC);
        if (p)
                p->p_stats->p_ru.ru_msgsnd++;
        if (control)
                clen = control->m_len;
#define snderr(errno)   { error = errno; splx(s); goto release; }

restart:
        error = sblock(&so->so_snd, SBLOCKWAIT(flags));
        if (error)
                goto out;
        do {
                s = splnet();
                if (so->so_state & SS_CANTSENDMORE)
                        snderr(EPIPE);
                if (so->so_error) {
                        error = so->so_error;
                        so->so_error = 0;
                        splx(s);
                        goto release;
                }
                if ((so->so_state & SS_ISCONNECTED) == 0) {
                        /*
                         * `sendto' and `sendmsg' is allowed on a connection-
                         * based socket if it supports implied connect.
                         * Return ENOTCONN if not connected and no address is
                         * supplied.
                         */
                        if ((so->so_proto->pr_flags & PR_CONNREQUIRED) &&
                            (so->so_proto->pr_flags & PR_IMPLOPCL) == 0) {
                                if ((so->so_state & SS_ISCONFIRMING) == 0 &&
                                    !(resid == 0 && clen != 0))
                                        snderr(ENOTCONN);
                        } else if (addr == 0 && !(flags&MSG_HOLD))
                            snderr(so->so_proto->pr_flags & PR_CONNREQUIRED ?
                                   ENOTCONN : EDESTADDRREQ);
                }
                space = sbspace(&so->so_snd);
                if (flags & MSG_OOB)
                        space += 1024;
                if ((atomic && resid > so->so_snd.sb_hiwat) ||
                    clen > so->so_snd.sb_hiwat)
                        snderr(EMSGSIZE);
                if (space < resid + clen && uio &&
                    (atomic || space < so->so_snd.sb_lowat || space < clen)) {
                        if (so->so_state & SS_NBIO)
                                snderr(EWOULDBLOCK);
                        sbunlock(&so->so_snd);
                        error = sbwait(&so->so_snd);
                        splx(s);
                        if (error)
                                goto out;
                        goto restart;
                }
                splx(s);
                mp = &top;
                space -= clen;
                do {
                    if (uio == NULL) {
                        /*
                         * Data is prepackaged in "top".
                         */
                        resid = 0;
                        if (flags & MSG_EOR)
                                top->m_flags |= M_EOR;
                    } else {
                        boolean_t       funnel_state = TRUE;
                        int             chainmbufs = (sosendminchain > 0 && resid >= sosendminchain);
            
                        if (chainmbufs)
                            funnel_state = thread_funnel_set(network_flock, FALSE);
                        do {
                        KERNEL_DEBUG(DBG_FNC_SOSEND | DBG_FUNC_NONE, -1, 0, 0, 0, 0);
                        if (top == 0) {
                                MGETHDR(m, M_WAIT, MT_DATA);
                                mlen = MHLEN;
                                m->m_pkthdr.len = 0;
                                m->m_pkthdr.rcvif = (struct ifnet *)0;
                        } else {
                                MGET(m, M_WAIT, MT_DATA);
                                mlen = MLEN;
                        }
                        if (resid >= MINCLSIZE) {
                                MCLGET(m, M_WAIT);
                                if ((m->m_flags & M_EXT) == 0)
                                        goto nopages;
                                mlen = MCLBYTES;
                                len = min(min(mlen, resid), space);
                        } else {
nopages:
                                len = min(min(mlen, resid), space);
                                /*
                                 * For datagram protocols, leave room
                                 * for protocol headers in first mbuf.
                                 */
                                if (atomic && top == 0 && len < mlen)
                                        MH_ALIGN(m, len);
                        }
                        KERNEL_DEBUG(DBG_FNC_SOSEND | DBG_FUNC_NONE, -1, 0, 0, 0, 0);
                        space -= len;
                        error = uiomove(mtod(m, caddr_t), (int)len, uio);
                        resid = uio->uio_resid;
                        
                        m->m_len = len;
                        *mp = m;
                        top->m_pkthdr.len += len;
                        if (error) 
                            break;
                        mp = &m->m_next;
                        if (resid <= 0) {
                                if (flags & MSG_EOR)
                                        top->m_flags |= M_EOR;
                                break;
                        }
                    } while (space > 0 && (chainmbufs || atomic || resid < MINCLSIZE));
                    if (chainmbufs)
                        funnel_state = thread_funnel_set(network_flock, TRUE);
                    if (error)
                        goto release;
                    }
            
                    if (flags & (MSG_HOLD|MSG_SEND))
                    {   /* Enqueue for later, go away if HOLD */
                        register struct mbuf *mb1;
                        if (so->so_temp && (flags & MSG_FLUSH))
                        {       m_freem(so->so_temp);
                                so->so_temp = NULL;
                        }
                        if (so->so_temp)
                                so->so_tail->m_next = top;
                        else
                                so->so_temp = top;
                        mb1 = top;
                        while (mb1->m_next)
                                mb1 = mb1->m_next;
                        so->so_tail = mb1;
                        if (flags&MSG_HOLD)
                        {       top = NULL;
                                goto release;
                        }
                        top = so->so_temp;
                    }
                    if (dontroute)
                            so->so_options |= SO_DONTROUTE;
                    s = splnet();                               /* XXX */
                    kp = sotokextcb(so);
                    /* Compute flags here, for pru_send and NKEs */
                    sendflags = (flags & MSG_OOB) ? PRUS_OOB :
                        /*
                         * If the user set MSG_EOF, the protocol
                         * understands this flag and nothing left to
                         * send then use PRU_SEND_EOF instead of PRU_SEND.
                         */
                        ((flags & MSG_EOF) &&
                         (so->so_proto->pr_flags & PR_IMPLOPCL) &&
                         (resid <= 0)) ?
                                PRUS_EOF :
                        /* If there is more to send set PRUS_MORETOCOME */
                        (resid > 0 && space > 0) ? PRUS_MORETOCOME : 0;
                    while (kp)
                    {   if (kp->e_soif && kp->e_soif->sf_sosend)
                        {       error = (*kp->e_soif->sf_sosend)(so, &addr,
                                                                 &uio, &top,
                                                                 &control,
                                                                 &sendflags,
                                                                 kp);
                                if (error)
                                {       splx(s);
                                        if (error == EJUSTRETURN)
                                        {       sbunlock(&so->so_snd);
                                                return(0);
                                        }
                                        goto release;
                                }
                        }
                        kp = kp->e_next;
                    }

                    error = (*so->so_proto->pr_usrreqs->pru_send)(so,
                        sendflags, top, addr, control, p);
                    splx(s);
                    if (flags & MSG_SEND)
                        so->so_temp = NULL;

                    if (dontroute)
                            so->so_options &= ~SO_DONTROUTE;
                    clen = 0;
                    control = 0;
                    top = 0;
                    mp = &top;
                    if (error)
                        goto release;
                } while (resid && space > 0);
        } while (resid);

release:
        sbunlock(&so->so_snd);
out:
        if (top)
                m_freem(top);
        if (control)
                m_freem(control);

        KERNEL_DEBUG(DBG_FNC_SOSEND | DBG_FUNC_END,
                     so,
                     resid,
                     so->so_snd.sb_cc,
                     space,
                     error);

        return (error);
}

/*
 * Implement receive operations on a socket.
 * We depend on the way that records are added to the sockbuf
 * by sbappend*.  In particular, each record (mbufs linked through m_next)
 * must begin with an address if the protocol so specifies,
 * followed by an optional mbuf or mbufs containing ancillary data,
 * and then zero or more mbufs of data.
 * In order to avoid blocking network interrupts for the entire time here,
 * we splx() while doing the actual copy to user space.
 * Although the sockbuf is locked, new data may still be appended,
 * and thus we must maintain consistency of the sockbuf during that time.
 *
 * The caller may receive the data as a single mbuf chain by supplying
 * an mbuf **mp0 for use in returning the chain.  The uio is then used
 * only for the count in uio_resid.
 */
int
soreceive(so, psa, uio, mp0, controlp, flagsp)
        register struct socket *so;
        struct sockaddr **psa;
        struct uio *uio;
        struct mbuf **mp0;
        struct mbuf **controlp;
        int *flagsp;
{
        register struct mbuf *m, **mp;
        register int flags, len, error, s, offset;
        struct protosw *pr = so->so_proto;
        struct mbuf *nextrecord;
        int moff, type = 0;
        int orig_resid = uio->uio_resid;
        struct kextcb *kp;
        
        KERNEL_DEBUG(DBG_FNC_SORECEIVE | DBG_FUNC_START,
                     so,
                     uio->uio_resid,
                     so->so_rcv.sb_cc,
                     so->so_rcv.sb_lowat,
                     so->so_rcv.sb_hiwat);

        kp = sotokextcb(so);
        while (kp)
        {       if (kp->e_soif && kp->e_soif->sf_soreceive)
                {       error = (*kp->e_soif->sf_soreceive)(so, psa, &uio,
                                                            mp0, controlp,
                                                            flagsp, kp);
                        if (error)
                                return((error == EJUSTRETURN) ? 0 : error);
                }
                kp = kp->e_next;
        }

        mp = mp0;
        if (psa)
                *psa = 0;
        if (controlp)
                *controlp = 0;
        if (flagsp)
                flags = *flagsp &~ MSG_EOR;
        else
                flags = 0;
        /*
         * When SO_WANTOOBFLAG is set we try to get out-of-band data 
         * regardless of the flags argument. Here is the case were 
         * out-of-band data is not inline.
         */
        if ((flags & MSG_OOB) || 
            ((so->so_options & SO_WANTOOBFLAG) != 0 && 
             (so->so_options & SO_OOBINLINE) == 0 &&
             (so->so_oobmark || (so->so_state & SS_RCVATMARK)))) {
                m = m_get(M_WAIT, MT_DATA);
                error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK);
                if (error)
                        goto bad;
                do {
                        error = uiomove(mtod(m, caddr_t),
                            (int) min(uio->uio_resid, m->m_len), uio);
                        m = m_free(m);
                } while (uio->uio_resid && error == 0 && m);
bad:
                if (m)
                        m_freem(m);
                if ((so->so_options & SO_WANTOOBFLAG) != 0) {
                    if (error == EWOULDBLOCK || error == EINVAL) {
                        /* 
                         * Let's try to get normal data:
                         *  EWOULDBLOCK: out-of-band data not receive yet;
                         *  EINVAL: out-of-band data already read.
                         */
                        error = 0;
                        goto nooob;
                    } else if (error == 0 && flagsp)
                        *flagsp |= MSG_OOB;
                }
                KERNEL_DEBUG(DBG_FNC_SORECEIVE | DBG_FUNC_END, error,0,0,0,0);
                return (error);
        }
nooob:
        if (mp)
                *mp = (struct mbuf *)0;
        if (so->so_state & SS_ISCONFIRMING && uio->uio_resid)
                (*pr->pr_usrreqs->pru_rcvd)(so, 0);

restart:
        if (error = sblock(&so->so_rcv, SBLOCKWAIT(flags)))
        {
                KERNEL_DEBUG(DBG_FNC_SORECEIVE | DBG_FUNC_END, error,0,0,0,0);
                return (error);
        }
        s = splnet();

        m = so->so_rcv.sb_mb;
        /*
         * If we have less data than requested, block awaiting more
         * (subject to any timeout) if:
         *   1. the current count is less than the low water mark, or
         *   2. MSG_WAITALL is set, and it is possible to do the entire
         *      receive operation at once if we block (resid <= hiwat).
         *   3. MSG_DONTWAIT is not set
         * If MSG_WAITALL is set but resid is larger than the receive buffer,
         * we have to do the receive in sections, and thus risk returning
         * a short count if a timeout or signal occurs after we start.
         */
        if (m == 0 || (((flags & MSG_DONTWAIT) == 0 &&
            so->so_rcv.sb_cc < uio->uio_resid) &&
            (so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
            ((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
            m->m_nextpkt == 0 && (pr->pr_flags & PR_ATOMIC) == 0)) {
                KASSERT(m != 0 || !so->so_rcv.sb_cc, ("receive 1"));
                if (so->so_error) {
                        if (m)
                                goto dontblock;
                        error = so->so_error;
                        if ((flags & MSG_PEEK) == 0)
                                so->so_error = 0;
                        goto release;
                }
                if (so->so_state & SS_CANTRCVMORE) {
                        if (m)
                                goto dontblock;
                        else
                                goto release;
                }
                for (; m; m = m->m_next)
                        if (m->m_type == MT_OOBDATA  || (m->m_flags & M_EOR)) {
                                m = so->so_rcv.sb_mb;
                                goto dontblock;
                        }
                if ((so->so_state & (SS_ISCONNECTED|SS_ISCONNECTING)) == 0 &&
                    (so->so_proto->pr_flags & PR_CONNREQUIRED)) {
                        error = ENOTCONN;
                        goto release;
                }
                if (uio->uio_resid == 0)
                        goto release;
                if ((so->so_state & SS_NBIO) || (flags & MSG_DONTWAIT)) {
                        error = EWOULDBLOCK;
                        goto release;
                }
                sbunlock(&so->so_rcv);
                if (socket_debug)
                    printf("Waiting for socket data\n");
                error = sbwait(&so->so_rcv);
                if (socket_debug)
                    printf("SORECEIVE - sbwait returned %d\n", error);
                splx(s);
                if (error)
                {
                    KERNEL_DEBUG(DBG_FNC_SORECEIVE | DBG_FUNC_END, error,0,0,0,0);
                    return (error);
                }
                goto restart;
        }
dontblock:
#ifdef notyet /* XXXX */
        if (uio->uio_procp)
                uio->uio_procp->p_stats->p_ru.ru_msgrcv++;
#endif
        nextrecord = m->m_nextpkt;
        if ((pr->pr_flags & PR_ADDR) && m->m_type == MT_SONAME) {
                KASSERT(m->m_type == MT_SONAME, ("receive 1a"));
                orig_resid = 0;
                if (psa)
                        *psa = dup_sockaddr(mtod(m, struct sockaddr *),
                                            mp0 == 0);
                if (flags & MSG_PEEK) {
                        m = m->m_next;
                } else {
                        sbfree(&so->so_rcv, m);
                        MFREE(m, so->so_rcv.sb_mb);
                        m = so->so_rcv.sb_mb;
                }
        }
        while (m && m->m_type == MT_CONTROL && error == 0) {
                if (flags & MSG_PEEK) {
                        if (controlp)
                                *controlp = m_copy(m, 0, m->m_len);
                        m = m->m_next;
                } else {
                        sbfree(&so->so_rcv, m);
                        if (controlp) {
                                if (pr->pr_domain->dom_externalize &&
                                    mtod(m, struct cmsghdr *)->cmsg_type ==
                                    SCM_RIGHTS)
                                   error = (*pr->pr_domain->dom_externalize)(m);
                                *controlp = m;
                                so->so_rcv.sb_mb = m->m_next;
                                m->m_next = 0;
                                m = so->so_rcv.sb_mb;
                        } else {
                                MFREE(m, so->so_rcv.sb_mb);
                                m = so->so_rcv.sb_mb;
                        }
                }
                if (controlp) {
                        orig_resid = 0;
                        controlp = &(*controlp)->m_next;
                }
        }
        if (m) {
                if ((flags & MSG_PEEK) == 0)
                        m->m_nextpkt = nextrecord;
                type = m->m_type;
                if (type == MT_OOBDATA)
                        flags |= MSG_OOB;
        }
        moff = 0;
        offset = 0;
        while (m && uio->uio_resid > 0 && error == 0) {
                if (m->m_type == MT_OOBDATA) {
                        if (type != MT_OOBDATA)
                                break;
                } else if (type == MT_OOBDATA)
                        break;
#if 0
/*
 * This assertion needs rework.  The trouble is Appletalk is uses many
 * mbuf types (NOT listed in mbuf.h!) which will trigger this panic.
 * For now just remove the assertion...  CSM 9/98
 */
                else
                    KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
                        ("receive 3"));
#endif
               /*
                * Make sure to allways set MSG_OOB event when getting 
                * out of band data inline.
                */
                if ((so->so_options & SO_WANTOOBFLAG) != 0 &&
                    (so->so_options & SO_OOBINLINE) != 0 && 
                    (so->so_state & SS_RCVATMARK) != 0) {
                    flags |= MSG_OOB;
                }
                so->so_state &= ~SS_RCVATMARK;
                len = uio->uio_resid;
                if (so->so_oobmark && len > so->so_oobmark - offset)
                        len = so->so_oobmark - offset;
                if (len > m->m_len - moff)
                        len = m->m_len - moff;
                /*
                 * If mp is set, just pass back the mbufs.
                 * Otherwise copy them out via the uio, then free.
                 * Sockbuf must be consistent here (points to current mbuf,
                 * it points to next record) when we drop priority;
                 * we must note any additions to the sockbuf when we
                 * block interrupts again.
                 */
                if (mp == 0) {
                        splx(s);
                        error = uiomove(mtod(m, caddr_t) + moff, (int)len, uio);
                        s = splnet();
                        if (error)
                                goto release;
                } else
                        uio->uio_resid -= len;
                if (len == m->m_len - moff) {
                        if (m->m_flags & M_EOR)
                                flags |= MSG_EOR;
                        if (flags & MSG_PEEK) {
                                m = m->m_next;
                                moff = 0;
                        } else {
                                nextrecord = m->m_nextpkt;
                                sbfree(&so->so_rcv, m);
                                if (mp) {
                                        *mp = m;
                                        mp = &m->m_next;
                                        so->so_rcv.sb_mb = m = m->m_next;
                                        *mp = (struct mbuf *)0;
                                } else {
                                        MFREE(m, so->so_rcv.sb_mb);
                                        m = so->so_rcv.sb_mb;
                                }
                                if (m)
                                        m->m_nextpkt = nextrecord;
                        }
                } else {
                        if (flags & MSG_PEEK)
                                moff += len;
                        else {
                                if (mp)
                                        *mp = m_copym(m, 0, len, M_WAIT);
                                m->m_data += len;
                                m->m_len -= len;
                                so->so_rcv.sb_cc -= len;
                        }
                }
                if (so->so_oobmark) {
                        if ((flags & MSG_PEEK) == 0) {
                                so->so_oobmark -= len;
                                if (so->so_oobmark == 0) {
                                    so->so_state |= SS_RCVATMARK;
                                    postevent(so, 0, EV_OOB);
                                    break;
                                }
                        } else {
                                offset += len;
                                if (offset == so->so_oobmark)
                                        break;
                        }
                }
                if (flags & MSG_EOR)
                        break;
                /*
                 * If the MSG_WAITALL flag is set (for non-atomic socket),
                 * we must not quit until "uio->uio_resid == 0" or an error
                 * termination.  If a signal/timeout occurs, return
                 * with a short count but without error.
                 * Keep sockbuf locked against other readers.
                 */
                while (flags & MSG_WAITALL && m == 0 && uio->uio_resid > 0 &&
                    !sosendallatonce(so) && !nextrecord) {
                        if (so->so_error || so->so_state & SS_CANTRCVMORE)
                                break;
                        error = sbwait(&so->so_rcv);
                        if (error) {
                                sbunlock(&so->so_rcv);
                                splx(s);
                                KERNEL_DEBUG(DBG_FNC_SORECEIVE | DBG_FUNC_END, 0,0,0,0,0);
                                return (0);
                        }
                        m = so->so_rcv.sb_mb;
                        if (m)
                                nextrecord = m->m_nextpkt;
                }
        }

        if (m && pr->pr_flags & PR_ATOMIC) {
                if (so->so_options & SO_DONTTRUNC)
                        flags |= MSG_RCVMORE;
                else
                {       flags |= MSG_TRUNC;
                        if ((flags & MSG_PEEK) == 0)
                                (void) sbdroprecord(&so->so_rcv);
                }
        }
        if ((flags & MSG_PEEK) == 0) {
                if (m == 0)
                        so->so_rcv.sb_mb = nextrecord;
                if (pr->pr_flags & PR_WANTRCVD && so->so_pcb)
                        (*pr->pr_usrreqs->pru_rcvd)(so, flags);
        }
        if ((so->so_options & SO_WANTMORE) && so->so_rcv.sb_cc > 0)
                flags |= MSG_HAVEMORE;
        if (orig_resid == uio->uio_resid && orig_resid &&
            (flags & MSG_EOR) == 0 && (so->so_state & SS_CANTRCVMORE) == 0) {
                sbunlock(&so->so_rcv);
                splx(s);
                goto restart;
        }

        if (flagsp)
                *flagsp |= flags;
release:
        sbunlock(&so->so_rcv);
        splx(s);

        KERNEL_DEBUG(DBG_FNC_SORECEIVE | DBG_FUNC_END,
                     so,
                     uio->uio_resid,
                     so->so_rcv.sb_cc,
                     0,
                     error);

        return (error);
}

int
soshutdown(so, how)
        register struct socket *so;
        register int how;
{
        register struct protosw *pr = so->so_proto;
        struct kextcb *kp;
        int ret;


        KERNEL_DEBUG(DBG_FNC_SOSHUTDOWN | DBG_FUNC_START, 0,0,0,0,0);
        kp = sotokextcb(so);
        while (kp)
        {       if (kp->e_soif && kp->e_soif->sf_soshutdown)
                {       ret = (*kp->e_soif->sf_soshutdown)(so, how, kp);
                        if (ret)
                                return((ret == EJUSTRETURN) ? 0 : ret);
                }
                kp = kp->e_next;
        }

        how++;
        if (how & FREAD) {
                sorflush(so);
                postevent(so, 0, EV_RCLOSED);
        }
        if (how & FWRITE) {
            ret = ((*pr->pr_usrreqs->pru_shutdown)(so));
            postevent(so, 0, EV_WCLOSED);
            KERNEL_DEBUG(DBG_FNC_SOSHUTDOWN | DBG_FUNC_END, 0,0,0,0,0);
            return(ret);
        }

        KERNEL_DEBUG(DBG_FNC_SOSHUTDOWN | DBG_FUNC_END, 0,0,0,0,0);
        return (0);
}

void
sorflush(so)
        register struct socket *so;
{
        register struct sockbuf *sb = &so->so_rcv;
        register struct protosw *pr = so->so_proto;
        register int s, error;
        struct sockbuf asb;
        struct kextcb *kp;

        kp = sotokextcb(so);
        while (kp)
        {       if (kp->e_soif && kp->e_soif->sf_sorflush)
                {       if ((*kp->e_soif->sf_sorflush)(so, kp))
                                return;
                }
                kp = kp->e_next;
        }

        sb->sb_flags |= SB_NOINTR;
        (void) sblock(sb, M_WAIT);
        s = splimp();
        socantrcvmore(so);
        sbunlock(sb);
        selthreadclear(&sb->sb_sel);
        asb = *sb;
        bzero((caddr_t)sb, sizeof (*sb));
        splx(s);
        if (pr->pr_flags & PR_RIGHTS && pr->pr_domain->dom_dispose)
                (*pr->pr_domain->dom_dispose)(asb.sb_mb);
        sbrelease(&asb);
}

/*
 * Perhaps this routine, and sooptcopyout(), below, ought to come in
 * an additional variant to handle the case where the option value needs
 * to be some kind of integer, but not a specific size.
 * In addition to their use here, these functions are also called by the
 * protocol-level pr_ctloutput() routines.
 */
int
sooptcopyin(sopt, buf, len, minlen)
        struct  sockopt *sopt;
        void    *buf;
        size_t  len;
        size_t  minlen;
{
        size_t  valsize;

        /*
         * If the user gives us more than we wanted, we ignore it,
         * but if we don't get the minimum length the caller
         * wants, we return EINVAL.  On success, sopt->sopt_valsize
         * is set to however much we actually retrieved.
         */
        if ((valsize = sopt->sopt_valsize) < minlen)
                return EINVAL;
        if (valsize > len)
                sopt->sopt_valsize = valsize = len;

        if (sopt->sopt_p != 0)
                return (copyin(sopt->sopt_val, buf, valsize));

        bcopy(sopt->sopt_val, buf, valsize);
        return 0;
}

int
sosetopt(so, sopt)
        struct socket *so;
        struct sockopt *sopt;
{
        int     error, optval;
        struct  linger l;
        struct  timeval tv;
        short   val;
        struct kextcb *kp;

        kp = sotokextcb(so);
        while (kp)
        {       if (kp->e_soif && kp->e_soif->sf_socontrol)
                {       error = (*kp->e_soif->sf_socontrol)(so, sopt, kp);
                        if (error)
                                return((error == EJUSTRETURN) ? 0 : error);
                }
                kp = kp->e_next;
        }

        error = 0;
        if (sopt->sopt_level != SOL_SOCKET) {
                if (so->so_proto && so->so_proto->pr_ctloutput)
                        return ((*so->so_proto->pr_ctloutput)
                                  (so, sopt));
                error = ENOPROTOOPT;
        } else {
                switch (sopt->sopt_name) {
                case SO_LINGER:
                        error = sooptcopyin(sopt, &l, sizeof l, sizeof l);
                        if (error)
                                goto bad;

                        so->so_linger = l.l_linger;
                        if (l.l_onoff)
                                so->so_options |= SO_LINGER;
                        else
                                so->so_options &= ~SO_LINGER;
                        break;

                case SO_DEBUG:
                case SO_KEEPALIVE:
                case SO_DONTROUTE:
                case SO_USELOOPBACK:
                case SO_BROADCAST:
                case SO_REUSEADDR:
                case SO_REUSEPORT:
                case SO_OOBINLINE:
                case SO_TIMESTAMP:
                case SO_DONTTRUNC:
                case SO_WANTMORE:
         case SO_WANTOOBFLAG:
                        error = sooptcopyin(sopt, &optval, sizeof optval,
                                            sizeof optval);
                        if (error)
                                goto bad;
                        if (optval)
                                so->so_options |= sopt->sopt_name;
                        else
                                so->so_options &= ~sopt->sopt_name;
                        break;

                case SO_SNDBUF:
                case SO_RCVBUF:
                case SO_SNDLOWAT:
                case SO_RCVLOWAT:
                        error = sooptcopyin(sopt, &optval, sizeof optval,
                                            sizeof optval);
                        if (error)
                                goto bad;

                        /*
                         * Values < 1 make no sense for any of these
                         * options, so disallow them.
                         */
                        if (optval < 1) {
                                error = EINVAL;
                                goto bad;
                        }

                        switch (sopt->sopt_name) {
                        case SO_SNDBUF:
                        case SO_RCVBUF:
                                if (sbreserve(sopt->sopt_name == SO_SNDBUF ?
                                              &so->so_snd : &so->so_rcv,
                                              (u_long) optval) == 0) {
                                        error = ENOBUFS;
                                        goto bad;
                                }
                                break;

                        /*
                         * Make sure the low-water is never greater than
                         * the high-water.
                         */
                        case SO_SNDLOWAT:
                                so->so_snd.sb_lowat =
                                    (optval > so->so_snd.sb_hiwat) ?
                                    so->so_snd.sb_hiwat : optval;
                                break;
                        case SO_RCVLOWAT:
                                so->so_rcv.sb_lowat =
                                    (optval > so->so_rcv.sb_hiwat) ?
                                    so->so_rcv.sb_hiwat : optval;
                                break;
                        }
                        break;

                case SO_SNDTIMEO:
                case SO_RCVTIMEO:
                        error = sooptcopyin(sopt, &tv, sizeof tv,
                                            sizeof tv);
                        if (error)
                                goto bad;

                        if (tv.tv_sec > SHRT_MAX / hz - hz) {
                                error = EDOM;
                                goto bad;
                        }
                        val = tv.tv_sec * hz + tv.tv_usec / tick;

                        switch (sopt->sopt_name) {
                        case SO_SNDTIMEO:
                                so->so_snd.sb_timeo = val;
                                break;
                        case SO_RCVTIMEO:
                                so->so_rcv.sb_timeo = val;
                                break;
                        }
                        break;

                case SO_NKE:
                {       struct so_nke nke;
                        struct NFDescriptor *nf1, *nf2 = NULL;

                        error = sooptcopyin(sopt, &nke,
                                            sizeof nke, sizeof nke);
                        if (error)
                          goto bad;

                        error = nke_insert(so, &nke);
                        break;
                }

                default:
                        error = ENOPROTOOPT;
                        break;
                }
                if (error == 0 && so->so_proto && so->so_proto->pr_ctloutput) {
                        (void) ((*so->so_proto->pr_ctloutput)
                                  (so, sopt));
                }
        }
bad:
        return (error);
}

/* Helper routine for getsockopt */
int
sooptcopyout(sopt, buf, len)
        struct  sockopt *sopt;
        void    *buf;
        size_t  len;
{
        int     error;
        size_t  valsize;

        error = 0;

        /*
         * Documented get behavior is that we always return a value,
         * possibly truncated to fit in the user's buffer.
         * Traditional behavior is that we always tell the user
         * precisely how much we copied, rather than something useful
         * like the total amount we had available for her.
         * Note that this interface is not idempotent; the entire answer must
         * generated ahead of time.
         */
        valsize = min(len, sopt->sopt_valsize);
        sopt->sopt_valsize = valsize;
        if (sopt->sopt_val != 0) {
                if (sopt->sopt_p != 0)
                        error = copyout(buf, sopt->sopt_val, valsize);
                else
                        bcopy(buf, sopt->sopt_val, valsize);
        }
        return error;
}

int
sogetopt(so, sopt)
        struct socket *so;
        struct sockopt *sopt;
{
        int     error, optval;
        struct  linger l;
        struct  timeval tv;
        struct mbuf  *m;
        struct kextcb *kp;

        kp = sotokextcb(so);
        while (kp)
        {       if (kp->e_soif && kp->e_soif->sf_socontrol)
                {       error = (*kp->e_soif->sf_socontrol)(so, sopt, kp);
                        if (error)
                                return((error == EJUSTRETURN) ? 0 : error);
                }
                kp = kp->e_next;
        }

        error = 0;
        if (sopt->sopt_level != SOL_SOCKET) {
                if (so->so_proto && so->so_proto->pr_ctloutput) {
                        return ((*so->so_proto->pr_ctloutput)
                                  (so, sopt));
                } else
                        return (ENOPROTOOPT);
        } else {
                switch (sopt->sopt_name) {
                case SO_LINGER:
                        l.l_onoff = so->so_options & SO_LINGER;
                        l.l_linger = so->so_linger;
                        error = sooptcopyout(sopt, &l, sizeof l);
                        break;

                case SO_USELOOPBACK:
                case SO_DONTROUTE:
                case SO_DEBUG:
                case SO_KEEPALIVE:
                case SO_REUSEADDR:
                case SO_REUSEPORT:
                case SO_BROADCAST:
                case SO_OOBINLINE:
                case SO_TIMESTAMP:
                case SO_DONTTRUNC:
                case SO_WANTMORE:
         case SO_WANTOOBFLAG:
                        optval = so->so_options & sopt->sopt_name;
integer:
                        error = sooptcopyout(sopt, &optval, sizeof optval);
                        break;

                case SO_TYPE:
                        optval = so->so_type;
                        goto integer;

                case SO_NREAD:
                {       int pkt_total;
                        struct mbuf *m1;

                        pkt_total = 0;
                        m1 = so->so_rcv.sb_mb;
                        if (so->so_proto->pr_flags & PR_ATOMIC)
                        {
#if 0
                                kprintf("SKT CC: %d\n", so->so_rcv.sb_cc);
#endif
                                while (m1)
                                {       if (m1->m_type == MT_DATA)
                                                pkt_total += m1->m_len;
#if 0
                                        kprintf("CNT: %d/%d\n", m1->m_len, pkt_total);
#endif
                                        m1 = m1->m_next;
                                }
                                optval = pkt_total;
                        } else
                                optval = so->so_rcv.sb_cc;
#if 0
                        kprintf("RTN: %d\n", optval);
#endif
                        goto integer;
                }
                case SO_ERROR:
                        optval = so->so_error;
                        so->so_error = 0;
                        goto integer;

                case SO_SNDBUF:
                        optval = so->so_snd.sb_hiwat;
                        goto integer;

                case SO_RCVBUF:
                        optval = so->so_rcv.sb_hiwat;
                        goto integer;

                case SO_SNDLOWAT:
                        optval = so->so_snd.sb_lowat;
                        goto integer;

                case SO_RCVLOWAT:
                        optval = so->so_rcv.sb_lowat;
                        goto integer;

                case SO_SNDTIMEO:
                case SO_RCVTIMEO:
                        optval = (sopt->sopt_name == SO_SNDTIMEO ?
                                  so->so_snd.sb_timeo : so->so_rcv.sb_timeo);

                        tv.tv_sec = optval / hz;
                        tv.tv_usec = (optval % hz) * tick;
                        error = sooptcopyout(sopt, &tv, sizeof tv);
                        break;                  

                default:
                        error = ENOPROTOOPT;
                        break;
                }
                return (error);
        }
}

void
sohasoutofband(so)
        register struct socket *so;
{
        struct proc *p;

        struct kextcb *kp;

        kp = sotokextcb(so);
        while (kp)
        {       if (kp->e_soif && kp->e_soif->sf_sohasoutofband)
                {       if ((*kp->e_soif->sf_sohasoutofband)(so, kp))
                                return;
                }
                kp = kp->e_next;
        }
        if (so->so_pgid < 0)
                gsignal(-so->so_pgid, SIGURG);
        else if (so->so_pgid > 0 && (p = pfind(so->so_pgid)) != 0)
                psignal(p, SIGURG);
        selwakeup(&so->so_rcv.sb_sel);
}

/*
 * Network filter support
 */
/* Run the list of filters, creating extension control blocks */
sfilter_init(register struct socket *so)
{       struct kextcb *kp, **kpp;
        struct protosw *prp;
        struct NFDescriptor *nfp;

        prp = so->so_proto;
        nfp = prp->pr_sfilter.tqh_first; /* non-null */
        kpp = &so->so_ext;
        kp = NULL;
        while (nfp)
        {       MALLOC(kp, struct kextcb *, sizeof(*kp),
                            M_TEMP, M_WAITOK);
                if (kp == NULL)
                        return(ENOBUFS); /* so_free will clean up */
                *kpp = kp;
                kpp = &kp->e_next;
                kp->e_next = NULL;
                kp->e_fcb = NULL;
                kp->e_nfd = nfp;
                kp->e_soif = nfp->nf_soif;
                kp->e_sout = nfp->nf_soutil;
                /*
                 * Ignore return value for create
                 * Everyone gets a chance at startup
                 */
                if (kp->e_soif && kp->e_soif->sf_socreate)
                        (*kp->e_soif->sf_socreate)(so, prp, kp);
                nfp = nfp->nf_next.tqe_next;
        }
        return(0);
}


/*
 * Run the list of filters, freeing extension control blocks
 * Assumes the soif/soutil blocks have been handled.
 */
sfilter_term(struct socket *so)
{       struct kextcb *kp, *kp1;

        kp = so->so_ext;
        while (kp)
        {       kp1 = kp->e_next;
                /*
                 * Ignore return code on termination; everyone must
                 *  get terminated.
                 */
                if (kp->e_soif && kp->e_soif->sf_sofree)
                        kp->e_soif->sf_sofree(so, kp);
                FREE(kp, M_TEMP);
                kp = kp1;
        }
        return(0);
}


int
sopoll(struct socket *so, int events, struct ucred *cred, void * wql)
{
        struct proc *p = current_proc();
        int revents = 0;
        int s = splnet();

        if (events & (POLLIN | POLLRDNORM))
                if (soreadable(so))
                        revents |= events & (POLLIN | POLLRDNORM);

        if (events & (POLLOUT | POLLWRNORM))
                if (sowriteable(so))
                        revents |= events & (POLLOUT | POLLWRNORM);

        if (events & (POLLPRI | POLLRDBAND))
                if (so->so_oobmark || (so->so_state & SS_RCVATMARK))
                        revents |= events & (POLLPRI | POLLRDBAND);

        if (revents == 0) {
                if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) {
                        so->so_rcv.sb_flags |= SB_SEL;
                        selrecord(p, &so->so_rcv.sb_sel, wql);
                }

                if (events & (POLLOUT | POLLWRNORM)) {
                        so->so_snd.sb_flags |= SB_SEL;
                        selrecord(p, &so->so_snd.sb_sel, wql);
                }
        }

        splx(s);
        return (revents);
}

/*#### IPv6 Integration. Added new routines */
int
sooptgetm(struct sockopt *sopt, struct mbuf **mp)
{
        struct mbuf *m, *m_prev;
        int sopt_size = sopt->sopt_valsize;

        MGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT, MT_DATA);
        if (m == 0)
                return ENOBUFS;
        if (sopt_size > MLEN) {
                MCLGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT);
                if ((m->m_flags & M_EXT) == 0) {
                        m_free(m);
                        return ENOBUFS;
                }
                m->m_len = min(MCLBYTES, sopt_size);
        } else {
                m->m_len = min(MLEN, sopt_size);
        }
        sopt_size -= m->m_len;
        *mp = m;
        m_prev = m;

        while (sopt_size) {
                MGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT, MT_DATA);
                if (m == 0) {
                        m_freem(*mp);
                        return ENOBUFS;
                }
                if (sopt_size > MLEN) {
                        MCLGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT);
                        if ((m->m_flags & M_EXT) == 0) {
                                m_freem(*mp);
                                return ENOBUFS;
                        }
                        m->m_len = min(MCLBYTES, sopt_size);
                } else {
                        m->m_len = min(MLEN, sopt_size);
                }
                sopt_size -= m->m_len;
                m_prev->m_next = m;
                m_prev = m;
        }
        return 0;
}

/* XXX; copyin sopt data into mbuf chain for (__FreeBSD__ < 3) routines. */
int
sooptmcopyin(struct sockopt *sopt, struct mbuf *m)
{
        struct mbuf *m0 = m;

        if (sopt->sopt_val == NULL)
                return 0;
        while (m != NULL && sopt->sopt_valsize >= m->m_len) {
                if (sopt->sopt_p != NULL) {
                        int error;

                        error = copyin(sopt->sopt_val, mtod(m, char *),
                                       m->m_len);
                        if (error != 0) {
                                m_freem(m0);
                                return(error);
                        }
                } else
                        bcopy(sopt->sopt_val, mtod(m, char *), m->m_len);
                sopt->sopt_valsize -= m->m_len;
                (caddr_t)sopt->sopt_val += m->m_len;
                m = m->m_next;
        }
        if (m != NULL) /* should be allocated enoughly at ip6_sooptmcopyin() */
                panic("sooptmcopyin");
        return 0;
}

/* XXX; copyout mbuf chain data into soopt for (__FreeBSD__ < 3) routines. */
int
sooptmcopyout(struct sockopt *sopt, struct mbuf *m)
{
        struct mbuf *m0 = m;
        size_t valsize = 0;

        if (sopt->sopt_val == NULL)
                return 0;
        while (m != NULL && sopt->sopt_valsize >= m->m_len) {
                if (sopt->sopt_p != NULL) {
                        int error;

                        error = copyout(mtod(m, char *), sopt->sopt_val,
                                       m->m_len);
                        if (error != 0) {
                                m_freem(m0);
                                return(error);
                        }
                } else
                        bcopy(mtod(m, char *), sopt->sopt_val, m->m_len);
               sopt->sopt_valsize -= m->m_len;
               (caddr_t)sopt->sopt_val += m->m_len;
               valsize += m->m_len;
               m = m->m_next;
        }
        if (m != NULL) {
                /* enough soopt buffer should be given from user-land */
                m_freem(m0);
                return(EINVAL);
        }
        sopt->sopt_valsize = valsize;
        return 0;
}