uipc_syscalls.c

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/*-
 * Copyright (c) 1982, 1986, 1989, 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * sendfile(2) and related extensions:
 * Copyright (c) 1998, David Greenman. 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.
 * 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_syscalls.c     8.4 (Berkeley) 2/21/94
 */

#include <sys/cdefs.h>
__FBSDID("$BSDSUniX$");

#include "opt_capsicum.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_sctp.h"
#include "opt_compat.h"
#include "opt_ktrace.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/capability.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sysproto.h>
#include <sys/malloc.h>
#include <sys/filedesc.h>
#include <sys/event.h>
#include <sys/proc.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/filio.h>
#include <sys/jail.h>
#include <sys/mount.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/sf_buf.h>
#include <sys/sysent.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/signalvar.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#ifdef KTRACE
#include <sys/ktrace.h>
#endif
#ifdef COMPAT_32BIT
#include <compat/compat32bit/compat32bit_util.h>
#endif

#include <net/vnet.h>

#include <security/audit/audit.h>
#include <security/mac/mac_framework.h>

#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pageout.h>
#include <vm/vm_kern.h>
#include <vm/vm_extern.h>

#if defined(INET) || defined(INET6)
#ifdef SCTP
#include <netinet/sctp.h>
#include <netinet/sctp_peeloff.h>
#endif /* SCTP */
#endif /* INET || INET6 */

/*
 * Creation flags, OR'ed into socket() and socketpair() type argument.
 * For stable/9, these are supported but not exposed in the header file.
 */
#define SOCK_CLOEXEC    0x10000000
#define SOCK_NONBLOCK   0x20000000

static int sendit(struct thread *td, int s, struct msghdr *mp, int flags);
static int recvit(struct thread *td, int s, struct msghdr *mp, void *namelenp);

static int accept1(struct thread *td, struct accept_args *uap, int compat);
static int do_sendfile(struct thread *td, struct sendfile_args *uap, int compat);
static int getsockname1(struct thread *td, struct getsockname_args *uap,
                        int compat);
static int getpeername1(struct thread *td, struct getpeername_args *uap,
                        int compat);

/*
 * NSFBUFS-related variables and associated sysctls
 */
int nsfbufs;
int nsfbufspeak;
int nsfbufsused;

SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufs, CTLFLAG_RDTUN, &nsfbufs, 0,
    "Maximum number of sendfile(2) sf_bufs available");
SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufspeak, CTLFLAG_RD, &nsfbufspeak, 0,
    "Number of sendfile(2) sf_bufs at peak usage");
SYSCTL_INT(_kern_ipc, OID_AUTO, nsfbufsused, CTLFLAG_RD, &nsfbufsused, 0,
    "Number of sendfile(2) sf_bufs in use");

/*
 * Convert a user file descriptor to a kernel file entry and check that, if
 * it is a capability, the right rights are present. A reference on the file
 * entry is held upon returning.
 */
static int
getsock_cap(struct filedesc *fdp, int fd, cap_rights_t rights,
    struct file **fpp, u_int *fflagp)
{
        struct file *fp;
#ifdef CAPABILITIES
        struct file *fp_fromcap;
        int error;
#endif

        fp = NULL;
        if ((fdp == NULL) || ((fp = fget_unlocked(fdp, fd)) == NULL))
                return (EBADF);
#ifdef CAPABILITIES
        /*
         * If the file descriptor is for a capability, test rights and use
         * the file descriptor referenced by the capability.
         */
        error = cap_funwrap(fp, rights, &fp_fromcap);
        if (error) {
                fdrop(fp, curthread);
                return (error);
        }
        if (fp != fp_fromcap) {
                fhold(fp_fromcap);
                fdrop(fp, curthread);
                fp = fp_fromcap;
        }
#endif /* CAPABILITIES */
        if (fp->f_type != DTYPE_SOCKET) {
                fdrop(fp, curthread);
                return (ENOTSOCK);
        }
        if (fflagp != NULL)
                *fflagp = fp->f_flag;
        *fpp = fp;
        return (0);
}

/*
 * System call interface to the socket abstraction.
 */
#if defined(COMPAT_43)
#define COMPAT_OLDSOCK
#endif

int
sys_socket(td, uap)
        struct thread *td;
        struct socket_args /* {
                int     domain;
                int     type;
                int     protocol;
        } */ *uap;
{
        struct filedesc *fdp;
        struct socket *so;
        struct file *fp;
        int fd, error, type, oflag, fflag;

        AUDIT_ARG_SOCKET(uap->domain, uap->type, uap->protocol);

        type = uap->type;
        oflag = 0;
        fflag = 0;
        if ((type & SOCK_CLOEXEC) != 0) {
                type &= ~SOCK_CLOEXEC;
                oflag |= O_CLOEXEC;
        }
        if ((type & SOCK_NONBLOCK) != 0) {
                type &= ~SOCK_NONBLOCK;
                fflag |= FNONBLOCK;
        }

#ifdef MAC
        error = mac_socket_check_create(td->td_ucred, uap->domain, type,
            uap->protocol);
        if (error)
                return (error);
#endif
        fdp = td->td_proc->p_fd;
        error = falloc(td, &fp, &fd, oflag);
        if (error)
                return (error);
        /* An extra reference on `fp' has been held for us by falloc(). */
        error = socreate(uap->domain, &so, type, uap->protocol,
            td->td_ucred, td);
        if (error) {
                fdclose(fdp, fp, fd, td);
        } else {
                finit(fp, FREAD | FWRITE | fflag, DTYPE_SOCKET, so, &socketops);
                if ((fflag & FNONBLOCK) != 0)
                        (void) fo_ioctl(fp, FIONBIO, &fflag, td->td_ucred, td);
                td->td_retval[0] = fd;
        }
        fdrop(fp, td);
        return (error);
}

/* ARGSUSED */
int
sys_bind(td, uap)
        struct thread *td;
        struct bind_args /* {
                int     s;
                caddr_t name;
                int     namelen;
        } */ *uap;
{
        struct sockaddr *sa;
        int error;

        if ((error = getsockaddr(&sa, uap->name, uap->namelen)) != 0)
                return (error);

        error = kern_bind(td, uap->s, sa);
        free(sa, M_SONAME);
        return (error);
}

int
kern_bind(td, fd, sa)
        struct thread *td;
        int fd;
        struct sockaddr *sa;
{
        struct socket *so;
        struct file *fp;
        int error;

        AUDIT_ARG_FD(fd);
        error = getsock_cap(td->td_proc->p_fd, fd, CAP_BIND, &fp, NULL);
        if (error)
                return (error);
        so = fp->f_data;
#ifdef KTRACE
        if (KTRPOINT(td, KTR_STRUCT))
                ktrsockaddr(sa);
#endif
#ifdef MAC
        error = mac_socket_check_bind(td->td_ucred, so, sa);
        if (error == 0)
#endif
                error = sobind(so, sa, td);
        fdrop(fp, td);
        return (error);
}

/* ARGSUSED */
int
sys_listen(td, uap)
        struct thread *td;
        struct listen_args /* {
                int     s;
                int     backlog;
        } */ *uap;
{
        struct socket *so;
        struct file *fp;
        int error;

        AUDIT_ARG_FD(uap->s);
        error = getsock_cap(td->td_proc->p_fd, uap->s, CAP_LISTEN, &fp, NULL);
        if (error == 0) {
                so = fp->f_data;
#ifdef MAC
                error = mac_socket_check_listen(td->td_ucred, so);
                if (error == 0)
#endif
                        error = solisten(so, uap->backlog, td);
                fdrop(fp, td);
        }
        return(error);
}

/*
 * accept1()
 */
static int
accept1(td, uap, compat)
        struct thread *td;
        struct accept_args /* {
                int     s;
                struct sockaddr * __restrict name;
                socklen_t       * __restrict anamelen;
        } */ *uap;
        int compat;
{
        struct sockaddr *name;
        socklen_t namelen;
        struct file *fp;
        int error;

        if (uap->name == NULL)
                return (kern_accept(td, uap->s, NULL, NULL, NULL));

        error = copyin(uap->anamelen, &namelen, sizeof (namelen));
        if (error)
                return (error);

        error = kern_accept(td, uap->s, &name, &namelen, &fp);

        /*
         * return a namelen of zero for older code which might
         * ignore the return value from accept.
         */
        if (error) {
                (void) copyout(&namelen,
                    uap->anamelen, sizeof(*uap->anamelen));
                return (error);
        }

        if (error == 0 && name != NULL) {
#ifdef COMPAT_OLDSOCK
                if (compat)
                        ((struct osockaddr *)name)->sa_family =
                            name->sa_family;
#endif
                error = copyout(name, uap->name, namelen);
        }
        if (error == 0)
                error = copyout(&namelen, uap->anamelen,
                    sizeof(namelen));
        if (error)
                fdclose(td->td_proc->p_fd, fp, td->td_retval[0], td);
        fdrop(fp, td);
        free(name, M_SONAME);
        return (error);
}

int
kern_accept(struct thread *td, int s, struct sockaddr **name,
    socklen_t *namelen, struct file **fp)
{
        struct filedesc *fdp;
        struct file *headfp, *nfp = NULL;
        struct sockaddr *sa = NULL;
        int error;
        struct socket *head, *so;
        int fd;
        u_int fflag;
        pid_t pgid;
        int tmp;

        if (name) {
                *name = NULL;
                if (*namelen < 0)
                        return (EINVAL);
        }

        AUDIT_ARG_FD(s);
        fdp = td->td_proc->p_fd;
        error = getsock_cap(fdp, s, CAP_ACCEPT, &headfp, &fflag);
        if (error)
                return (error);
        head = headfp->f_data;
        if ((head->so_options & SO_ACCEPTCONN) == 0) {
                error = EINVAL;
                goto done;
        }
#ifdef MAC
        error = mac_socket_check_accept(td->td_ucred, head);
        if (error != 0)
                goto done;
#endif
        error = falloc(td, &nfp, &fd, 0);
        if (error)
                goto done;
        ACCEPT_LOCK();
        if ((head->so_state & SS_NBIO) && TAILQ_EMPTY(&head->so_comp)) {
                ACCEPT_UNLOCK();
                error = EWOULDBLOCK;
                goto noconnection;
        }
        while (TAILQ_EMPTY(&head->so_comp) && head->so_error == 0) {
                if (head->so_rcv.sb_state & SBS_CANTRCVMORE) {
                        head->so_error = ECONNABORTED;
                        break;
                }
                error = msleep(&head->so_timeo, &accept_mtx, PSOCK | PCATCH,
                    "accept", 0);
                if (error) {
                        ACCEPT_UNLOCK();
                        goto noconnection;
                }
        }
        if (head->so_error) {
                error = head->so_error;
                head->so_error = 0;
                ACCEPT_UNLOCK();
                goto noconnection;
        }
        so = TAILQ_FIRST(&head->so_comp);
        KASSERT(!(so->so_qstate & SQ_INCOMP), ("accept1: so SQ_INCOMP"));
        KASSERT(so->so_qstate & SQ_COMP, ("accept1: so not SQ_COMP"));

        /*
         * Before changing the flags on the socket, we have to bump the
         * reference count.  Otherwise, if the protocol calls sofree(),
         * the socket will be released due to a zero refcount.
         */
        SOCK_LOCK(so);                  /* soref() and so_state update */
        soref(so);                      /* file descriptor reference */

        TAILQ_REMOVE(&head->so_comp, so, so_list);
        head->so_qlen--;
        so->so_state |= (head->so_state & SS_NBIO);
        so->so_qstate &= ~SQ_COMP;
        so->so_head = NULL;

        SOCK_UNLOCK(so);
        ACCEPT_UNLOCK();

        /* An extra reference on `nfp' has been held for us by falloc(). */
        td->td_retval[0] = fd;

        /* connection has been removed from the listen queue */
        KNOTE_UNLOCKED(&head->so_rcv.sb_sel.si_note, 0);

        pgid = fgetown(&head->so_sigio);
        if (pgid != 0)
                fsetown(pgid, &so->so_sigio);

        finit(nfp, fflag, DTYPE_SOCKET, so, &socketops);
        /* Sync socket nonblocking/async state with file flags */
        tmp = fflag & FNONBLOCK;
        (void) fo_ioctl(nfp, FIONBIO, &tmp, td->td_ucred, td);
        tmp = fflag & FASYNC;
        (void) fo_ioctl(nfp, FIOASYNC, &tmp, td->td_ucred, td);
        sa = 0;
        error = soaccept(so, &sa);
        if (error) {
                /*
                 * return a namelen of zero for older code which might
                 * ignore the return value from accept.
                 */
                if (name)
                        *namelen = 0;
                goto noconnection;
        }
        if (sa == NULL) {
                if (name)
                        *namelen = 0;
                goto done;
        }
        if (name) {
                /* check sa_len before it is destroyed */
                if (*namelen > sa->sa_len)
                        *namelen = sa->sa_len;
#ifdef KTRACE
                if (KTRPOINT(td, KTR_STRUCT))
                        ktrsockaddr(sa);
#endif
                *name = sa;
                sa = NULL;
        }
noconnection:
        if (sa)
                free(sa, M_SONAME);

        /*
         * close the new descriptor, assuming someone hasn't ripped it
         * out from under us.
         */
        if (error)
                fdclose(fdp, nfp, fd, td);

        /*
         * Release explicitly held references before returning.  We return
         * a reference on nfp to the caller on success if they request it.
         */
done:
        if (fp != NULL) {
                if (error == 0) {
                        *fp = nfp;
                        nfp = NULL;
                } else
                        *fp = NULL;
        }
        if (nfp != NULL)
                fdrop(nfp, td);
        fdrop(headfp, td);
        return (error);
}

int
sys_accept(td, uap)
        struct thread *td;
        struct accept_args *uap;
{

        return (accept1(td, uap, 0));
}

#ifdef COMPAT_OLDSOCK
int
oaccept(td, uap)
        struct thread *td;
        struct accept_args *uap;
{

        return (accept1(td, uap, 1));
}
#endif /* COMPAT_OLDSOCK */

/* ARGSUSED */
int
sys_connect(td, uap)
        struct thread *td;
        struct connect_args /* {
                int     s;
                caddr_t name;
                int     namelen;
        } */ *uap;
{
        struct sockaddr *sa;
        int error;

        error = getsockaddr(&sa, uap->name, uap->namelen);
        if (error)
                return (error);

        error = kern_connect(td, uap->s, sa);
        free(sa, M_SONAME);
        return (error);
}


int
kern_connect(td, fd, sa)
        struct thread *td;
        int fd;
        struct sockaddr *sa;
{
        struct socket *so;
        struct file *fp;
        int error;
        int interrupted = 0;

        AUDIT_ARG_FD(fd);
        error = getsock_cap(td->td_proc->p_fd, fd, CAP_CONNECT, &fp, NULL);
        if (error)
                return (error);
        so = fp->f_data;
        if (so->so_state & SS_ISCONNECTING) {
                error = EALREADY;
                goto done1;
        }
#ifdef KTRACE
        if (KTRPOINT(td, KTR_STRUCT))
                ktrsockaddr(sa);
#endif
#ifdef MAC
        error = mac_socket_check_connect(td->td_ucred, so, sa);
        if (error)
                goto bad;
#endif
        error = soconnect(so, sa, td);
        if (error)
                goto bad;
        if ((so->so_state & SS_NBIO) && (so->so_state & SS_ISCONNECTING)) {
                error = EINPROGRESS;
                goto done1;
        }
        SOCK_LOCK(so);
        while ((so->so_state & SS_ISCONNECTING) && so->so_error == 0) {
                error = msleep(&so->so_timeo, SOCK_MTX(so), PSOCK | PCATCH,
                    "connec", 0);
                if (error) {
                        if (error == EINTR || error == ERESTART)
                                interrupted = 1;
                        break;
                }
        }
        if (error == 0) {
                error = so->so_error;
                so->so_error = 0;
        }
        SOCK_UNLOCK(so);
bad:
        if (!interrupted)
                so->so_state &= ~SS_ISCONNECTING;
        if (error == ERESTART)
                error = EINTR;
done1:
        fdrop(fp, td);
        return (error);
}

int
kern_socketpair(struct thread *td, int domain, int type, int protocol,
    int *rsv)
{
        struct filedesc *fdp = td->td_proc->p_fd;
        struct file *fp1, *fp2;
        struct socket *so1, *so2;
        int fd, error, oflag, fflag;

        AUDIT_ARG_SOCKET(domain, type, protocol);

        oflag = 0;
        fflag = 0;
        if ((type & SOCK_CLOEXEC) != 0) {
                type &= ~SOCK_CLOEXEC;
                oflag |= O_CLOEXEC;
        }
        if ((type & SOCK_NONBLOCK) != 0) {
                type &= ~SOCK_NONBLOCK;
                fflag |= FNONBLOCK;
        }
#ifdef MAC
        /* We might want to have a separate check for socket pairs. */
        error = mac_socket_check_create(td->td_ucred, domain, type,
            protocol);
        if (error)
                return (error);
#endif
        error = socreate(domain, &so1, type, protocol, td->td_ucred, td);
        if (error)
                return (error);
        error = socreate(domain, &so2, type, protocol, td->td_ucred, td);
        if (error)
                goto free1;
        /* On success extra reference to `fp1' and 'fp2' is set by falloc. */
        error = falloc(td, &fp1, &fd, oflag);
        if (error)
                goto free2;
        rsv[0] = fd;
        fp1->f_data = so1;      /* so1 already has ref count */
        error = falloc(td, &fp2, &fd, oflag);
        if (error)
                goto free3;
        fp2->f_data = so2;      /* so2 already has ref count */
        rsv[1] = fd;
        error = soconnect2(so1, so2);
        if (error)
                goto free4;
        if (type == SOCK_DGRAM) {
                /*
                 * Datagram socket connection is asymmetric.
                 */
                 error = soconnect2(so2, so1);
                 if (error)
                        goto free4;
        }
        finit(fp1, FREAD | FWRITE | fflag, DTYPE_SOCKET, fp1->f_data,
            &socketops);
        finit(fp2, FREAD | FWRITE | fflag, DTYPE_SOCKET, fp2->f_data,
            &socketops);
        if ((fflag & FNONBLOCK) != 0) {
                (void) fo_ioctl(fp1, FIONBIO, &fflag, td->td_ucred, td);
                (void) fo_ioctl(fp2, FIONBIO, &fflag, td->td_ucred, td);
        }
        fdrop(fp1, td);
        fdrop(fp2, td);
        return (0);
free4:
        fdclose(fdp, fp2, rsv[1], td);
        fdrop(fp2, td);
free3:
        fdclose(fdp, fp1, rsv[0], td);
        fdrop(fp1, td);
free2:
        if (so2 != NULL)
                (void)soclose(so2);
free1:
        if (so1 != NULL)
                (void)soclose(so1);
        return (error);
}

int
sys_socketpair(struct thread *td, struct socketpair_args *uap)
{
        int error, sv[2];

        error = kern_socketpair(td, uap->domain, uap->type,
            uap->protocol, sv);
        if (error)
                return (error);
        error = copyout(sv, uap->rsv, 2 * sizeof(int));
        if (error) {
                (void)kern_close(td, sv[0]);
                (void)kern_close(td, sv[1]);
        }
        return (error);
}

static int
sendit(td, s, mp, flags)
        struct thread *td;
        int s;
        struct msghdr *mp;
        int flags;
{
        struct mbuf *control;
        struct sockaddr *to;
        int error;

#ifdef CAPABILITY_MODE
        if (IN_CAPABILITY_MODE(td) && (mp->msg_name != NULL))
                return (ECAPMODE);
#endif

        if (mp->msg_name != NULL) {
                error = getsockaddr(&to, mp->msg_name, mp->msg_namelen);
                if (error) {
                        to = NULL;
                        goto bad;
                }
                mp->msg_name = to;
        } else {
                to = NULL;
        }

        if (mp->msg_control) {
                if (mp->msg_controllen < sizeof(struct cmsghdr)
#ifdef COMPAT_OLDSOCK
                    && mp->msg_flags != MSG_COMPAT
#endif
                ) {
                        error = EINVAL;
                        goto bad;
                }
                error = sockargs(&control, mp->msg_control,
                    mp->msg_controllen, MT_CONTROL);
                if (error)
                        goto bad;
#ifdef COMPAT_OLDSOCK
                if (mp->msg_flags == MSG_COMPAT) {
                        struct cmsghdr *cm;

                        M_PREPEND(control, sizeof(*cm), M_WAIT);
                        cm = mtod(control, struct cmsghdr *);
                        cm->cmsg_len = control->m_len;
                        cm->cmsg_level = SOL_SOCKET;
                        cm->cmsg_type = SCM_RIGHTS;
                }
#endif
        } else {
                control = NULL;
        }

        error = kern_sendit(td, s, mp, flags, control, UIO_USERSPACE);

bad:
        if (to)
                free(to, M_SONAME);
        return (error);
}

int
kern_sendit(td, s, mp, flags, control, segflg)
        struct thread *td;
        int s;
        struct msghdr *mp;
        int flags;
        struct mbuf *control;
        enum uio_seg segflg;
{
        struct file *fp;
        struct uio auio;
        struct iovec *iov;
        struct socket *so;
        int i, error;
        ssize_t len;
        cap_rights_t rights;
#ifdef KTRACE
        struct uio *ktruio = NULL;
#endif

        AUDIT_ARG_FD(s);
        rights = CAP_WRITE;
        if (mp->msg_name != NULL)
                rights |= CAP_CONNECT;
        error = getsock_cap(td->td_proc->p_fd, s, rights, &fp, NULL);
        if (error)
                return (error);
        so = (struct socket *)fp->f_data;

#ifdef KTRACE
        if (mp->msg_name != NULL && KTRPOINT(td, KTR_STRUCT))
                ktrsockaddr(mp->msg_name);
#endif
#ifdef MAC
        if (mp->msg_name != NULL) {
                error = mac_socket_check_connect(td->td_ucred, so,
                    mp->msg_name);
                if (error)
                        goto bad;
        }
        error = mac_socket_check_send(td->td_ucred, so);
        if (error)
                goto bad;
#endif

        auio.uio_iov = mp->msg_iov;
        auio.uio_iovcnt = mp->msg_iovlen;
        auio.uio_segflg = segflg;
        auio.uio_rw = UIO_WRITE;
        auio.uio_td = td;
        auio.uio_offset = 0;                    /* XXX */
        auio.uio_resid = 0;
        iov = mp->msg_iov;
        for (i = 0; i < mp->msg_iovlen; i++, iov++) {
                if ((auio.uio_resid += iov->iov_len) < 0) {
                        error = EINVAL;
                        goto bad;
                }
        }
#ifdef KTRACE
        if (KTRPOINT(td, KTR_GENIO))
                ktruio = cloneuio(&auio);
#endif
        len = auio.uio_resid;
        error = sosend(so, mp->msg_name, &auio, 0, control, flags, td);
        if (error) {
                if (auio.uio_resid != len && (error == ERESTART ||
                    error == EINTR || error == EWOULDBLOCK))
                        error = 0;
                /* Generation of SIGPIPE can be controlled per socket */
                if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
                    !(flags & MSG_NOSIGNAL)) {
                        PROC_LOCK(td->td_proc);
                        tdsignal(td, SIGPIPE);
                        PROC_UNLOCK(td->td_proc);
                }
        }
        if (error == 0)
                td->td_retval[0] = len - auio.uio_resid;
#ifdef KTRACE
        if (ktruio != NULL) {
                ktruio->uio_resid = td->td_retval[0];
                ktrgenio(s, UIO_WRITE, ktruio, error);
        }
#endif
bad:
        fdrop(fp, td);
        return (error);
}

int
sys_sendto(td, uap)
        struct thread *td;
        struct sendto_args /* {
                int     s;
                caddr_t buf;
                size_t  len;
                int     flags;
                caddr_t to;
                int     tolen;
        } */ *uap;
{
        struct msghdr msg;
        struct iovec aiov;
        int error;

        msg.msg_name = uap->to;
        msg.msg_namelen = uap->tolen;
        msg.msg_iov = &aiov;
        msg.msg_iovlen = 1;
        msg.msg_control = 0;
#ifdef COMPAT_OLDSOCK
        msg.msg_flags = 0;
#endif
        aiov.iov_base = uap->buf;
        aiov.iov_len = uap->len;
        error = sendit(td, uap->s, &msg, uap->flags);
        return (error);
}

#ifdef COMPAT_OLDSOCK
int
osend(td, uap)
        struct thread *td;
        struct osend_args /* {
                int     s;
                caddr_t buf;
                int     len;
                int     flags;
        } */ *uap;
{
        struct msghdr msg;
        struct iovec aiov;
        int error;

        msg.msg_name = 0;
        msg.msg_namelen = 0;
        msg.msg_iov = &aiov;
        msg.msg_iovlen = 1;
        aiov.iov_base = uap->buf;
        aiov.iov_len = uap->len;
        msg.msg_control = 0;
        msg.msg_flags = 0;
        error = sendit(td, uap->s, &msg, uap->flags);
        return (error);
}

int
osendmsg(td, uap)
        struct thread *td;
        struct osendmsg_args /* {
                int     s;
                caddr_t msg;
                int     flags;
        } */ *uap;
{
        struct msghdr msg;
        struct iovec *iov;
        int error;

        error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
        if (error)
                return (error);
        error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
        if (error)
                return (error);
        msg.msg_iov = iov;
        msg.msg_flags = MSG_COMPAT;
        error = sendit(td, uap->s, &msg, uap->flags);
        free(iov, M_IOV);
        return (error);
}
#endif

int
sys_sendmsg(td, uap)
        struct thread *td;
        struct sendmsg_args /* {
                int     s;
                caddr_t msg;
                int     flags;
        } */ *uap;
{
        struct msghdr msg;
        struct iovec *iov;
        int error;

        error = copyin(uap->msg, &msg, sizeof (msg));
        if (error)
                return (error);
        error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
        if (error)
                return (error);
        msg.msg_iov = iov;
#ifdef COMPAT_OLDSOCK
        msg.msg_flags = 0;
#endif
        error = sendit(td, uap->s, &msg, uap->flags);
        free(iov, M_IOV);
        return (error);
}

int
kern_recvit(td, s, mp, fromseg, controlp)
        struct thread *td;
        int s;
        struct msghdr *mp;
        enum uio_seg fromseg;
        struct mbuf **controlp;
{
        struct uio auio;
        struct iovec *iov;
        int i;
        ssize_t len;
        int error;
        struct mbuf *m, *control = 0;
        caddr_t ctlbuf;
        struct file *fp;
        struct socket *so;
        struct sockaddr *fromsa = 0;
#ifdef KTRACE
        struct uio *ktruio = NULL;
#endif

        if (controlp != NULL)
                *controlp = NULL;

        AUDIT_ARG_FD(s);
        error = getsock_cap(td->td_proc->p_fd, s, CAP_READ, &fp, NULL);
        if (error)
                return (error);
        so = fp->f_data;

#ifdef MAC
        error = mac_socket_check_receive(td->td_ucred, so);
        if (error) {
                fdrop(fp, td);
                return (error);
        }
#endif

        auio.uio_iov = mp->msg_iov;
        auio.uio_iovcnt = mp->msg_iovlen;
        auio.uio_segflg = UIO_USERSPACE;
        auio.uio_rw = UIO_READ;
        auio.uio_td = td;
        auio.uio_offset = 0;                    /* XXX */
        auio.uio_resid = 0;
        iov = mp->msg_iov;
        for (i = 0; i < mp->msg_iovlen; i++, iov++) {
                if ((auio.uio_resid += iov->iov_len) < 0) {
                        fdrop(fp, td);
                        return (EINVAL);
                }
        }
#ifdef KTRACE
        if (KTRPOINT(td, KTR_GENIO))
                ktruio = cloneuio(&auio);
#endif
        len = auio.uio_resid;
        error = soreceive(so, &fromsa, &auio, (struct mbuf **)0,
            (mp->msg_control || controlp) ? &control : (struct mbuf **)0,
            &mp->msg_flags);
        if (error) {
                if (auio.uio_resid != len && (error == ERESTART ||
                    error == EINTR || error == EWOULDBLOCK))
                        error = 0;
        }
#ifdef KTRACE
        if (ktruio != NULL) {
                ktruio->uio_resid = len - auio.uio_resid;
                ktrgenio(s, UIO_READ, ktruio, error);
        }
#endif
        if (error)
                goto out;
        td->td_retval[0] = len - auio.uio_resid;
        if (mp->msg_name) {
                len = mp->msg_namelen;
                if (len <= 0 || fromsa == 0)
                        len = 0;
                else {
                        /* save sa_len before it is destroyed by MSG_COMPAT */
                        len = MIN(len, fromsa->sa_len);
#ifdef COMPAT_OLDSOCK
                        if (mp->msg_flags & MSG_COMPAT)
                                ((struct osockaddr *)fromsa)->sa_family =
                                    fromsa->sa_family;
#endif
                        if (fromseg == UIO_USERSPACE) {
                                error = copyout(fromsa, mp->msg_name,
                                    (unsigned)len);
                                if (error)
                                        goto out;
                        } else
                                bcopy(fromsa, mp->msg_name, len);
                }
                mp->msg_namelen = len;
        }
        if (mp->msg_control && controlp == NULL) {
#ifdef COMPAT_OLDSOCK
                /*
                 * We assume that old recvmsg calls won't receive access
                 * rights and other control info, esp. as control info
                 * is always optional and those options didn't exist in 4.3.
                 * If we receive rights, trim the cmsghdr; anything else
                 * is tossed.
                 */
                if (control && mp->msg_flags & MSG_COMPAT) {
                        if (mtod(control, struct cmsghdr *)->cmsg_level !=
                            SOL_SOCKET ||
                            mtod(control, struct cmsghdr *)->cmsg_type !=
                            SCM_RIGHTS) {
                                mp->msg_controllen = 0;
                                goto out;
                        }
                        control->m_len -= sizeof (struct cmsghdr);
                        control->m_data += sizeof (struct cmsghdr);
                }
#endif
                len = mp->msg_controllen;
                m = control;
                mp->msg_controllen = 0;
                ctlbuf = mp->msg_control;

                while (m && len > 0) {
                        unsigned int tocopy;

                        if (len >= m->m_len)
                                tocopy = m->m_len;
                        else {
                                mp->msg_flags |= MSG_CTRUNC;
                                tocopy = len;
                        }

                        if ((error = copyout(mtod(m, caddr_t),
                                        ctlbuf, tocopy)) != 0)
                                goto out;

                        ctlbuf += tocopy;
                        len -= tocopy;
                        m = m->m_next;
                }
                mp->msg_controllen = ctlbuf - (caddr_t)mp->msg_control;
        }
out:
        fdrop(fp, td);
#ifdef KTRACE
        if (fromsa && KTRPOINT(td, KTR_STRUCT))
                ktrsockaddr(fromsa);
#endif
        if (fromsa)
                free(fromsa, M_SONAME);

        if (error == 0 && controlp != NULL)  
                *controlp = control;
        else  if (control)
                m_freem(control);

        return (error);
}

static int
recvit(td, s, mp, namelenp)
        struct thread *td;
        int s;
        struct msghdr *mp;
        void *namelenp;
{
        int error;

        error = kern_recvit(td, s, mp, UIO_USERSPACE, NULL);
        if (error)
                return (error);
        if (namelenp) {
                error = copyout(&mp->msg_namelen, namelenp, sizeof (socklen_t));
#ifdef COMPAT_OLDSOCK
                if (mp->msg_flags & MSG_COMPAT)
                        error = 0;      /* old recvfrom didn't check */
#endif
        }
        return (error);
}

int
sys_recvfrom(td, uap)
        struct thread *td;
        struct recvfrom_args /* {
                int     s;
                caddr_t buf;
                size_t  len;
                int     flags;
                struct sockaddr * __restrict    from;
                socklen_t * __restrict fromlenaddr;
        } */ *uap;
{
        struct msghdr msg;
        struct iovec aiov;
        int error;

        if (uap->fromlenaddr) {
                error = copyin(uap->fromlenaddr,
                    &msg.msg_namelen, sizeof (msg.msg_namelen));
                if (error)
                        goto done2;
        } else {
                msg.msg_namelen = 0;
        }
        msg.msg_name = uap->from;
        msg.msg_iov = &aiov;
        msg.msg_iovlen = 1;
        aiov.iov_base = uap->buf;
        aiov.iov_len = uap->len;
        msg.msg_control = 0;
        msg.msg_flags = uap->flags;
        error = recvit(td, uap->s, &msg, uap->fromlenaddr);
done2:
        return(error);
}

#ifdef COMPAT_OLDSOCK
int
orecvfrom(td, uap)
        struct thread *td;
        struct recvfrom_args *uap;
{

        uap->flags |= MSG_COMPAT;
        return (sys_recvfrom(td, uap));
}
#endif

#ifdef COMPAT_OLDSOCK
int
orecv(td, uap)
        struct thread *td;
        struct orecv_args /* {
                int     s;
                caddr_t buf;
                int     len;
                int     flags;
        } */ *uap;
{
        struct msghdr msg;
        struct iovec aiov;
        int error;

        msg.msg_name = 0;
        msg.msg_namelen = 0;
        msg.msg_iov = &aiov;
        msg.msg_iovlen = 1;
        aiov.iov_base = uap->buf;
        aiov.iov_len = uap->len;
        msg.msg_control = 0;
        msg.msg_flags = uap->flags;
        error = recvit(td, uap->s, &msg, NULL);
        return (error);
}

/*
 * Old recvmsg.  This code takes advantage of the fact that the old msghdr
 * overlays the new one, missing only the flags, and with the (old) access
 * rights where the control fields are now.
 */
int
orecvmsg(td, uap)
        struct thread *td;
        struct orecvmsg_args /* {
                int     s;
                struct  omsghdr *msg;
                int     flags;
        } */ *uap;
{
        struct msghdr msg;
        struct iovec *iov;
        int error;

        error = copyin(uap->msg, &msg, sizeof (struct omsghdr));
        if (error)
                return (error);
        error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
        if (error)
                return (error);
        msg.msg_flags = uap->flags | MSG_COMPAT;
        msg.msg_iov = iov;
        error = recvit(td, uap->s, &msg, &uap->msg->msg_namelen);
        if (msg.msg_controllen && error == 0)
                error = copyout(&msg.msg_controllen,
                    &uap->msg->msg_accrightslen, sizeof (int));
        free(iov, M_IOV);
        return (error);
}
#endif

int
sys_recvmsg(td, uap)
        struct thread *td;
        struct recvmsg_args /* {
                int     s;
                struct  msghdr *msg;
                int     flags;
        } */ *uap;
{
        struct msghdr msg;
        struct iovec *uiov, *iov;
        int error;

        error = copyin(uap->msg, &msg, sizeof (msg));
        if (error)
                return (error);
        error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
        if (error)
                return (error);
        msg.msg_flags = uap->flags;
#ifdef COMPAT_OLDSOCK
        msg.msg_flags &= ~MSG_COMPAT;
#endif
        uiov = msg.msg_iov;
        msg.msg_iov = iov;
        error = recvit(td, uap->s, &msg, NULL);
        if (error == 0) {
                msg.msg_iov = uiov;
                error = copyout(&msg, uap->msg, sizeof(msg));
        }
        free(iov, M_IOV);
        return (error);
}

/* ARGSUSED */
int
sys_shutdown(td, uap)
        struct thread *td;
        struct shutdown_args /* {
                int     s;
                int     how;
        } */ *uap;
{
        struct socket *so;
        struct file *fp;
        int error;

        AUDIT_ARG_FD(uap->s);
        error = getsock_cap(td->td_proc->p_fd, uap->s, CAP_SHUTDOWN, &fp,
            NULL);
        if (error == 0) {
                so = fp->f_data;
                error = soshutdown(so, uap->how);
                fdrop(fp, td);
        }
        return (error);
}

/* ARGSUSED */
int
sys_setsockopt(td, uap)
        struct thread *td;
        struct setsockopt_args /* {
                int     s;
                int     level;
                int     name;
                caddr_t val;
                int     valsize;
        } */ *uap;
{

        return (kern_setsockopt(td, uap->s, uap->level, uap->name,
            uap->val, UIO_USERSPACE, uap->valsize));
}

int
kern_setsockopt(td, s, level, name, val, valseg, valsize)
        struct thread *td;
        int s;
        int level;
        int name;
        void *val;
        enum uio_seg valseg;
        socklen_t valsize;
{
        int error;
        struct socket *so;
        struct file *fp;
        struct sockopt sopt;

        if (val == NULL && valsize != 0)
                return (EFAULT);
        if ((int)valsize < 0)
                return (EINVAL);

        sopt.sopt_dir = SOPT_SET;
        sopt.sopt_level = level;
        sopt.sopt_name = name;
        sopt.sopt_val = val;
        sopt.sopt_valsize = valsize;
        switch (valseg) {
        case UIO_USERSPACE:
                sopt.sopt_td = td;
                break;
        case UIO_SYSSPACE:
                sopt.sopt_td = NULL;
                break;
        default:
                panic("kern_setsockopt called with bad valseg");
        }

        AUDIT_ARG_FD(s);
        error = getsock_cap(td->td_proc->p_fd, s, CAP_SETSOCKOPT, &fp, NULL);
        if (error == 0) {
                so = fp->f_data;
                error = sosetopt(so, &sopt);
                fdrop(fp, td);
        }
        return(error);
}

/* ARGSUSED */
int
sys_getsockopt(td, uap)
        struct thread *td;
        struct getsockopt_args /* {
                int     s;
                int     level;
                int     name;
                void * __restrict       val;
                socklen_t * __restrict avalsize;
        } */ *uap;
{
        socklen_t valsize;
        int     error;

        if (uap->val) {
                error = copyin(uap->avalsize, &valsize, sizeof (valsize));
                if (error)
                        return (error);
        }

        error = kern_getsockopt(td, uap->s, uap->level, uap->name,
            uap->val, UIO_USERSPACE, &valsize);

        if (error == 0)
                error = copyout(&valsize, uap->avalsize, sizeof (valsize));
        return (error);
}

/*
 * Kernel version of getsockopt.
 * optval can be a userland or userspace. optlen is always a kernel pointer.
 */
int
kern_getsockopt(td, s, level, name, val, valseg, valsize)
        struct thread *td;
        int s;
        int level;
        int name;
        void *val;
        enum uio_seg valseg;
        socklen_t *valsize;
{
        int error;
        struct  socket *so;
        struct file *fp;
        struct  sockopt sopt;

        if (val == NULL)
                *valsize = 0;
        if ((int)*valsize < 0)
                return (EINVAL);

        sopt.sopt_dir = SOPT_GET;
        sopt.sopt_level = level;
        sopt.sopt_name = name;
        sopt.sopt_val = val;
        sopt.sopt_valsize = (size_t)*valsize; /* checked non-negative above */
        switch (valseg) {
        case UIO_USERSPACE:
                sopt.sopt_td = td;
                break;
        case UIO_SYSSPACE:
                sopt.sopt_td = NULL;
                break;
        default:
                panic("kern_getsockopt called with bad valseg");
        }

        AUDIT_ARG_FD(s);
        error = getsock_cap(td->td_proc->p_fd, s, CAP_GETSOCKOPT, &fp, NULL);
        if (error == 0) {
                so = fp->f_data;
                error = sogetopt(so, &sopt);
                *valsize = sopt.sopt_valsize;
                fdrop(fp, td);
        }
        return (error);
}

/*
 * getsockname1() - Get socket name.
 */
/* ARGSUSED */
static int
getsockname1(td, uap, compat)
        struct thread *td;
        struct getsockname_args /* {
                int     fdes;
                struct sockaddr * __restrict asa;
                socklen_t * __restrict alen;
        } */ *uap;
        int compat;
{
        struct sockaddr *sa;
        socklen_t len;
        int error;

        error = copyin(uap->alen, &len, sizeof(len));
        if (error)
                return (error);

        error = kern_getsockname(td, uap->fdes, &sa, &len);
        if (error)
                return (error);

        if (len != 0) {
#ifdef COMPAT_OLDSOCK
                if (compat)
                        ((struct osockaddr *)sa)->sa_family = sa->sa_family;
#endif
                error = copyout(sa, uap->asa, (u_int)len);
        }
        free(sa, M_SONAME);
        if (error == 0)
                error = copyout(&len, uap->alen, sizeof(len));
        return (error);
}

int
kern_getsockname(struct thread *td, int fd, struct sockaddr **sa,
    socklen_t *alen)
{
        struct socket *so;
        struct file *fp;
        socklen_t len;
        int error;

        if (*alen < 0)
                return (EINVAL);

        AUDIT_ARG_FD(fd);
        error = getsock_cap(td->td_proc->p_fd, fd, CAP_GETSOCKNAME, &fp, NULL);
        if (error)
                return (error);
        so = fp->f_data;
        *sa = NULL;
        CURVNET_SET(so->so_vnet);
        error = (*so->so_proto->pr_usrreqs->pru_sockaddr)(so, sa);
        CURVNET_RESTORE();
        if (error)
                goto bad;
        if (*sa == NULL)
                len = 0;
        else
                len = MIN(*alen, (*sa)->sa_len);
        *alen = len;
#ifdef KTRACE
        if (KTRPOINT(td, KTR_STRUCT))
                ktrsockaddr(*sa);
#endif
bad:
        fdrop(fp, td);
        if (error && *sa) {
                free(*sa, M_SONAME);
                *sa = NULL;
        }
        return (error);
}

int
sys_getsockname(td, uap)
        struct thread *td;
        struct getsockname_args *uap;
{

        return (getsockname1(td, uap, 0));
}

#ifdef COMPAT_OLDSOCK
int
ogetsockname(td, uap)
        struct thread *td;
        struct getsockname_args *uap;
{

        return (getsockname1(td, uap, 1));
}
#endif /* COMPAT_OLDSOCK */

/*
 * getpeername1() - Get name of peer for connected socket.
 */
/* ARGSUSED */
static int
getpeername1(td, uap, compat)
        struct thread *td;
        struct getpeername_args /* {
                int     fdes;
                struct sockaddr * __restrict    asa;
                socklen_t * __restrict  alen;
        } */ *uap;
        int compat;
{
        struct sockaddr *sa;
        socklen_t len;
        int error;

        error = copyin(uap->alen, &len, sizeof (len));
        if (error)
                return (error);

        error = kern_getpeername(td, uap->fdes, &sa, &len);
        if (error)
                return (error);

        if (len != 0) {
#ifdef COMPAT_OLDSOCK
                if (compat)
                        ((struct osockaddr *)sa)->sa_family = sa->sa_family;
#endif
                error = copyout(sa, uap->asa, (u_int)len);
        }
        free(sa, M_SONAME);
        if (error == 0)
                error = copyout(&len, uap->alen, sizeof(len));
        return (error);
}

int
kern_getpeername(struct thread *td, int fd, struct sockaddr **sa,
    socklen_t *alen)
{
        struct socket *so;
        struct file *fp;
        socklen_t len;
        int error;

        if (*alen < 0)
                return (EINVAL);

        AUDIT_ARG_FD(fd);
        error = getsock_cap(td->td_proc->p_fd, fd, CAP_GETPEERNAME, &fp, NULL);
        if (error)
                return (error);
        so = fp->f_data;
        if ((so->so_state & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) {
                error = ENOTCONN;
                goto done;
        }
        *sa = NULL;
        CURVNET_SET(so->so_vnet);
        error = (*so->so_proto->pr_usrreqs->pru_peeraddr)(so, sa);
        CURVNET_RESTORE();
        if (error)
                goto bad;
        if (*sa == NULL)
                len = 0;
        else
                len = MIN(*alen, (*sa)->sa_len);
        *alen = len;
#ifdef KTRACE
        if (KTRPOINT(td, KTR_STRUCT))
                ktrsockaddr(*sa);
#endif
bad:
        if (error && *sa) {
                free(*sa, M_SONAME);
                *sa = NULL;
        }
done:
        fdrop(fp, td);
        return (error);
}

int
sys_getpeername(td, uap)
        struct thread *td;
        struct getpeername_args *uap;
{

        return (getpeername1(td, uap, 0));
}

#ifdef COMPAT_OLDSOCK
int
ogetpeername(td, uap)
        struct thread *td;
        struct ogetpeername_args *uap;
{

        /* XXX uap should have type `getpeername_args *' to begin with. */
        return (getpeername1(td, (struct getpeername_args *)uap, 1));
}
#endif /* COMPAT_OLDSOCK */

int
sockargs(mp, buf, buflen, type)
        struct mbuf **mp;
        caddr_t buf;
        int buflen, type;
{
        struct sockaddr *sa;
        struct mbuf *m;
        int error;

        if ((u_int)buflen > MLEN) {
#ifdef COMPAT_OLDSOCK
                if (type == MT_SONAME && (u_int)buflen <= 112)
                        buflen = MLEN;          /* unix domain compat. hack */
                else
#endif
                        if ((u_int)buflen > MCLBYTES)
                                return (EINVAL);
        }
        m = m_get(M_WAIT, type);
        if ((u_int)buflen > MLEN)
                MCLGET(m, M_WAIT);
        m->m_len = buflen;
        error = copyin(buf, mtod(m, caddr_t), (u_int)buflen);
        if (error)
                (void) m_free(m);
        else {
                *mp = m;
                if (type == MT_SONAME) {
                        sa = mtod(m, struct sockaddr *);

#if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
                        if (sa->sa_family == 0 && sa->sa_len < AF_MAX)
                                sa->sa_family = sa->sa_len;
#endif
                        sa->sa_len = buflen;
                }
        }
        return (error);
}

int
getsockaddr(namp, uaddr, len)
        struct sockaddr **namp;
        caddr_t uaddr;
        size_t len;
{
        struct sockaddr *sa;
        int error;

        if (len > SOCK_MAXADDRLEN)
                return (ENAMETOOLONG);
        if (len < offsetof(struct sockaddr, sa_data[0]))
                return (EINVAL);
        sa = malloc(len, M_SONAME, M_WAITOK);
        error = copyin(uaddr, sa, len);
        if (error) {
                free(sa, M_SONAME);
        } else {
#if defined(COMPAT_OLDSOCK) && BYTE_ORDER != BIG_ENDIAN
                if (sa->sa_family == 0 && sa->sa_len < AF_MAX)
                        sa->sa_family = sa->sa_len;
#endif
                sa->sa_len = len;
                *namp = sa;
        }
        return (error);
}

#include <sys/condvar.h>

struct sendfile_sync {
        struct mtx      mtx;
        struct cv       cv;
        unsigned        count;
};

/*
 * Detach mapped page and release resources back to the system.
 */
void
sf_buf_mext(void *addr, void *args)
{
        vm_page_t m;
        struct sendfile_sync *sfs;

        m = sf_buf_page(args);
        sf_buf_free(args);
        vm_page_lock(m);
        vm_page_unwire(m, 0);
        /*
         * Check for the object going away on us. This can
         * happen since we don't hold a reference to it.
         * If so, we're responsible for freeing the page.
         */
        if (m->wire_count == 0 && m->object == NULL)
                vm_page_free(m);
        vm_page_unlock(m);
        if (addr == NULL)
                return;
        sfs = addr;
        mtx_lock(&sfs->mtx);
        KASSERT(sfs->count> 0, ("Sendfile sync botchup count == 0"));
        if (--sfs->count == 0)
                cv_signal(&sfs->cv);
        mtx_unlock(&sfs->mtx);
}

/*
 * sendfile(2)
 *
 * int sendfile(int fd, int s, off_t offset, size_t nbytes,
 *       struct sf_hdtr *hdtr, off_t *sbytes, int flags)
 *
 * Send a file specified by 'fd' and starting at 'offset' to a socket
 * specified by 's'. Send only 'nbytes' of the file or until EOF if nbytes ==
 * 0.  Optionally add a header and/or trailer to the socket output.  If
 * specified, write the total number of bytes sent into *sbytes.
 */
int
sys_sendfile(struct thread *td, struct sendfile_args *uap)
{

        return (do_sendfile(td, uap, 0));
}

static int
do_sendfile(struct thread *td, struct sendfile_args *uap, int compat)
{
        struct sf_hdtr hdtr;
        struct uio *hdr_uio, *trl_uio;
        int error;

        hdr_uio = trl_uio = NULL;

        if (uap->hdtr != NULL) {
                error = copyin(uap->hdtr, &hdtr, sizeof(hdtr));
                if (error)
                        goto out;
                if (hdtr.headers != NULL) {
                        error = copyinuio(hdtr.headers, hdtr.hdr_cnt, &hdr_uio);
                        if (error)
                                goto out;
                }
                if (hdtr.trailers != NULL) {
                        error = copyinuio(hdtr.trailers, hdtr.trl_cnt, &trl_uio);
                        if (error)
                                goto out;

                }
        }

        error = kern_sendfile(td, uap, hdr_uio, trl_uio, compat);
out:
        if (hdr_uio)
                free(hdr_uio, M_IOV);
        if (trl_uio)
                free(trl_uio, M_IOV);
        return (error);
}

#ifdef COMPAT_FREEBSD4
int
freebsd4_sendfile(struct thread *td, struct freebsd4_sendfile_args *uap)
{
        struct sendfile_args args;

        args.fd = uap->fd;
        args.s = uap->s;
        args.offset = uap->offset;
        args.nbytes = uap->nbytes;
        args.hdtr = uap->hdtr;
        args.sbytes = uap->sbytes;
        args.flags = uap->flags;

        return (do_sendfile(td, &args, 1));
}
#endif /* COMPAT_FREEBSD4 */

int
kern_sendfile(struct thread *td, struct sendfile_args *uap,
    struct uio *hdr_uio, struct uio *trl_uio, int compat)
{
        struct file *sock_fp;
        struct vnode *vp;
        struct vm_object *obj = NULL;
        struct socket *so = NULL;
        struct mbuf *m = NULL;
        struct sf_buf *sf;
        struct vm_page *pg;
        struct vattr va;
        off_t off, xfsize, fsbytes = 0, sbytes = 0, rem = 0;
        int error, hdrlen = 0, mnw = 0;
        int vfslocked;
        int bsize;
        struct sendfile_sync *sfs = NULL;

        /*
         * The file descriptor must be a regular file and have a
         * backing VM object.
         * File offset must be positive.  If it goes beyond EOF
         * we send only the header/trailer and no payload data.
         */
        AUDIT_ARG_FD(uap->fd);
        if ((error = fgetvp_read(td, uap->fd, CAP_READ, &vp)) != 0)
                goto out;
        vfslocked = VFS_LOCK_GIANT(vp->v_mount);
        vn_lock(vp, LK_SHARED | LK_RETRY);
        if (vp->v_type == VREG) {
                bsize = vp->v_mount->mnt_stat.f_iosize;
                if (uap->nbytes == 0) {
                        error = VOP_GETATTR(vp, &va, td->td_ucred);
                        if (error != 0) {
                                VOP_UNLOCK(vp, 0);
                                VFS_UNLOCK_GIANT(vfslocked);
                                obj = NULL;
                                goto out;
                        }
                        rem = va.va_size;
                } else
                        rem = uap->nbytes;
                obj = vp->v_object;
                if (obj != NULL) {
                        /*
                         * Temporarily increase the backing VM
                         * object's reference count so that a forced
                         * reclamation of its vnode does not
                         * immediately destroy it.
                         */
                        VM_OBJECT_LOCK(obj);
                        if ((obj->flags & OBJ_DEAD) == 0) {
                                vm_object_reference_locked(obj);
                                VM_OBJECT_UNLOCK(obj);
                        } else {
                                VM_OBJECT_UNLOCK(obj);
                                obj = NULL;
                        }
                }
        } else
                bsize = 0;      /* silence gcc */
        VOP_UNLOCK(vp, 0);
        VFS_UNLOCK_GIANT(vfslocked);
        if (obj == NULL) {
                error = EINVAL;
                goto out;
        }
        if (uap->offset < 0) {
                error = EINVAL;
                goto out;
        }

        /*
         * The socket must be a stream socket and connected.
         * Remember if it a blocking or non-blocking socket.
         */
        if ((error = getsock_cap(td->td_proc->p_fd, uap->s, CAP_WRITE,
            &sock_fp, NULL)) != 0)
                goto out;
        so = sock_fp->f_data;
        if (so->so_type != SOCK_STREAM) {
                error = EINVAL;
                goto out;
        }
        if ((so->so_state & SS_ISCONNECTED) == 0) {
                error = ENOTCONN;
                goto out;
        }
        /*
         * Do not wait on memory allocations but return ENOMEM for
         * caller to retry later.
         * XXX: Experimental.
         */
        if (uap->flags & SF_MNOWAIT)
                mnw = 1;

        if (uap->flags & SF_SYNC) {
                sfs = malloc(sizeof *sfs, M_TEMP, M_WAITOK | M_ZERO);
                mtx_init(&sfs->mtx, "sendfile", NULL, MTX_DEF);
                cv_init(&sfs->cv, "sendfile");
        }

#ifdef MAC
        error = mac_socket_check_send(td->td_ucred, so);
        if (error)
                goto out;
#endif

        /* If headers are specified copy them into mbufs. */
        if (hdr_uio != NULL) {
                hdr_uio->uio_td = td;
                hdr_uio->uio_rw = UIO_WRITE;
                if (hdr_uio->uio_resid > 0) {
                        /*
                         * In FBSD < 5.0 the nbytes to send also included
                         * the header.  If compat is specified subtract the
                         * header size from nbytes.
                         */
                        if (compat) {
                                if (uap->nbytes > hdr_uio->uio_resid)
                                        uap->nbytes -= hdr_uio->uio_resid;
                                else
                                        uap->nbytes = 0;
                        }
                        m = m_uiotombuf(hdr_uio, (mnw ? M_NOWAIT : M_WAITOK),
                            0, 0, 0);
                        if (m == NULL) {
                                error = mnw ? EAGAIN : ENOBUFS;
                                goto out;
                        }
                        hdrlen = m_length(m, NULL);
                }
        }

        /*
         * Protect against multiple writers to the socket.
         *
         * XXXRW: Historically this has assumed non-interruptibility, so now
         * we implement that, but possibly shouldn't.
         */
        (void)sblock(&so->so_snd, SBL_WAIT | SBL_NOINTR);

        /*
         * Loop through the pages of the file, starting with the requested
         * offset. Get a file page (do I/O if necessary), map the file page
         * into an sf_buf, attach an mbuf header to the sf_buf, and queue
         * it on the socket.
         * This is done in two loops.  The inner loop turns as many pages
         * as it can, up to available socket buffer space, without blocking
         * into mbufs to have it bulk delivered into the socket send buffer.
         * The outer loop checks the state and available space of the socket
         * and takes care of the overall progress.
         */
        for (off = uap->offset; ; ) {
                struct mbuf *mtail;
                int loopbytes;
                int space;
                int done;

                if ((uap->nbytes != 0 && uap->nbytes == fsbytes) ||
                    (uap->nbytes == 0 && va.va_size == fsbytes))
                        break;

                mtail = NULL;
                loopbytes = 0;
                space = 0;
                done = 0;

                /*
                 * Check the socket state for ongoing connection,
                 * no errors and space in socket buffer.
                 * If space is low allow for the remainder of the
                 * file to be processed if it fits the socket buffer.
                 * Otherwise block in waiting for sufficient space
                 * to proceed, or if the socket is nonblocking, return
                 * to userland with EAGAIN while reporting how far
                 * we've come.
                 * We wait until the socket buffer has significant free
                 * space to do bulk sends.  This makes good use of file
                 * system read ahead and allows packet segmentation
                 * offloading hardware to take over lots of work.  If
                 * we were not careful here we would send off only one
                 * sfbuf at a time.
                 */
                SOCKBUF_LOCK(&so->so_snd);
                if (so->so_snd.sb_lowat < so->so_snd.sb_hiwat / 2)
                        so->so_snd.sb_lowat = so->so_snd.sb_hiwat / 2;
retry_space:
                if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
                        error = EPIPE;
                        SOCKBUF_UNLOCK(&so->so_snd);
                        goto done;
                } else if (so->so_error) {
                        error = so->so_error;
                        so->so_error = 0;
                        SOCKBUF_UNLOCK(&so->so_snd);
                        goto done;
                }
                space = sbspace(&so->so_snd);
                if (space < rem &&
                    (space <= 0 ||
                     space < so->so_snd.sb_lowat)) {
                        if (so->so_state & SS_NBIO) {
                                SOCKBUF_UNLOCK(&so->so_snd);
                                error = EAGAIN;
                                goto done;
                        }
                        /*
                         * sbwait drops the lock while sleeping.
                         * When we loop back to retry_space the
                         * state may have changed and we retest
                         * for it.
                         */
                        error = sbwait(&so->so_snd);
                        /*
                         * An error from sbwait usually indicates that we've
                         * been interrupted by a signal. If we've sent anything
                         * then return bytes sent, otherwise return the error.
                         */
                        if (error) {
                                SOCKBUF_UNLOCK(&so->so_snd);
                                goto done;
                        }
                        goto retry_space;
                }
                SOCKBUF_UNLOCK(&so->so_snd);

                /*
                 * Reduce space in the socket buffer by the size of
                 * the header mbuf chain.
                 * hdrlen is set to 0 after the first loop.
                 */
                space -= hdrlen;

                vfslocked = VFS_LOCK_GIANT(vp->v_mount);
                error = vn_lock(vp, LK_SHARED);
                if (error != 0) {
                        VFS_UNLOCK_GIANT(vfslocked);
                        goto done;
                }
                error = VOP_GETATTR(vp, &va, td->td_ucred);
                if (error != 0 || off >= va.va_size) {
                        VOP_UNLOCK(vp, 0);
                        VFS_UNLOCK_GIANT(vfslocked);
                        goto done;
                }
                VFS_UNLOCK_GIANT(vfslocked);

                /*
                 * Loop and construct maximum sized mbuf chain to be bulk
                 * dumped into socket buffer.
                 */
                while (space > loopbytes) {
                        vm_pindex_t pindex;
                        vm_offset_t pgoff;
                        struct mbuf *m0;

                        /*
                         * Calculate the amount to transfer.
                         * Not to exceed a page, the EOF,
                         * or the passed in nbytes.
                         */
                        pgoff = (vm_offset_t)(off & PAGE_MASK);
                        rem = va.va_size - uap->offset;
                        if (uap->nbytes != 0)
                                rem = omin(rem, uap->nbytes);
                        rem -= fsbytes + loopbytes;
                        xfsize = omin(PAGE_SIZE - pgoff, rem);
                        xfsize = omin(space - loopbytes, xfsize);
                        if (xfsize <= 0) {
                                done = 1;               /* all data sent */
                                break;
                        }

                        /*
                         * Attempt to look up the page.  Allocate
                         * if not found or wait and loop if busy.
                         */
                        pindex = OFF_TO_IDX(off);
                        VM_OBJECT_LOCK(obj);
                        pg = vm_page_grab(obj, pindex, VM_ALLOC_NOBUSY |
                            VM_ALLOC_NORMAL | VM_ALLOC_WIRED | VM_ALLOC_RETRY);

                        /*
                         * Check if page is valid for what we need,
                         * otherwise initiate I/O.
                         * If we already turned some pages into mbufs,
                         * send them off before we come here again and
                         * block.
                         */
                        if (pg->valid && vm_page_is_valid(pg, pgoff, xfsize))
                                VM_OBJECT_UNLOCK(obj);
                        else if (m != NULL)
                                error = EAGAIN; /* send what we already got */
                        else if (uap->flags & SF_NODISKIO)
                                error = EBUSY;
                        else {
                                ssize_t resid;

                                VM_OBJECT_UNLOCK(obj);

                                /*
                                 * Get the page from backing store.
                                 * XXXMAC: Because we don't have fp->f_cred
                                 * here, we pass in NOCRED.  This is probably
                                 * wrong, but is consistent with our original
                                 * implementation.
                                 */
                                vfslocked = VFS_LOCK_GIANT(vp->v_mount);
                                error = vn_rdwr(UIO_READ, vp, NULL, MAXBSIZE,
                                    trunc_page(off), UIO_NOCOPY, IO_NODELOCKED |
                                    IO_VMIO | ((MAXBSIZE / bsize) << IO_SEQSHIFT),
                                    td->td_ucred, NOCRED, &resid, td);
                                VFS_UNLOCK_GIANT(vfslocked);
                                if (error)
                                        VM_OBJECT_LOCK(obj);
                                mbstat.sf_iocnt++;
                        }
                        if (error) {
                                vm_page_lock(pg);
                                vm_page_unwire(pg, 0);
                                /*
                                 * See if anyone else might know about
                                 * this page.  If not and it is not valid,
                                 * then free it.
                                 */
                                if (pg->wire_count == 0 && pg->valid == 0 &&
                                    pg->busy == 0 && !(pg->oflags & VPO_BUSY))
                                        vm_page_free(pg);
                                vm_page_unlock(pg);
                                VM_OBJECT_UNLOCK(obj);
                                if (error == EAGAIN)
                                        error = 0;      /* not a real error */
                                break;
                        }

                        /*
                         * Get a sendfile buf.  When allocating the
                         * first buffer for mbuf chain, we usually
                         * wait as long as necessary, but this wait
                         * can be interrupted.  For consequent
                         * buffers, do not sleep, since several
                         * threads might exhaust the buffers and then
                         * deadlock.
                         */
                        sf = sf_buf_alloc(pg, (mnw || m != NULL) ? SFB_NOWAIT :
                            SFB_CATCH);
                        if (sf == NULL) {
                                mbstat.sf_allocfail++;
                                vm_page_lock(pg);
                                vm_page_unwire(pg, 0);
                                KASSERT(pg->object != NULL,
                                    ("kern_sendfile: object disappeared"));
                                vm_page_unlock(pg);
                                if (m == NULL)
                                        error = (mnw ? EAGAIN : EINTR);
                                break;
                        }

                        /*
                         * Get an mbuf and set it up as having
                         * external storage.
                         */
                        m0 = m_get((mnw ? M_NOWAIT : M_WAITOK), MT_DATA);
                        if (m0 == NULL) {
                                error = (mnw ? EAGAIN : ENOBUFS);
                                sf_buf_mext(NULL, sf);
                                break;
                        }
                        MEXTADD(m0, sf_buf_kva(sf), PAGE_SIZE, sf_buf_mext,
                            sfs, sf, M_RDONLY, EXT_SFBUF);
                        m0->m_data = (char *)sf_buf_kva(sf) + pgoff;
                        m0->m_len = xfsize;

                        /* Append to mbuf chain. */
                        if (mtail != NULL)
                                mtail->m_next = m0;
                        else if (m != NULL)
                                m_last(m)->m_next = m0;
                        else
                                m = m0;
                        mtail = m0;

                        /* Keep track of bits processed. */
                        loopbytes += xfsize;
                        off += xfsize;

                        if (sfs != NULL) {
                                mtx_lock(&sfs->mtx);
                                sfs->count++;
                                mtx_unlock(&sfs->mtx);
                        }
                }

                VOP_UNLOCK(vp, 0);

                /* Add the buffer chain to the socket buffer. */
                if (m != NULL) {
                        int mlen, err;

                        mlen = m_length(m, NULL);
                        SOCKBUF_LOCK(&so->so_snd);
                        if (so->so_snd.sb_state & SBS_CANTSENDMORE) {
                                error = EPIPE;
                                SOCKBUF_UNLOCK(&so->so_snd);
                                goto done;
                        }
                        SOCKBUF_UNLOCK(&so->so_snd);
                        CURVNET_SET(so->so_vnet);
                        /* Avoid error aliasing. */
                        err = (*so->so_proto->pr_usrreqs->pru_send)
                                    (so, 0, m, NULL, NULL, td);
                        CURVNET_RESTORE();
                        if (err == 0) {
                                /*
                                 * We need two counters to get the
                                 * file offset and nbytes to send
                                 * right:
                                 * - sbytes contains the total amount
                                 *   of bytes sent, including headers.
                                 * - fsbytes contains the total amount
                                 *   of bytes sent from the file.
                                 */
                                sbytes += mlen;
                                fsbytes += mlen;
                                if (hdrlen) {
                                        fsbytes -= hdrlen;
                                        hdrlen = 0;
                                }
                        } else if (error == 0)
                                error = err;
                        m = NULL;       /* pru_send always consumes */
                }

                /* Quit outer loop on error or when we're done. */
                if (done) 
                        break;
                if (error)
                        goto done;
        }

        /*
         * Send trailers. Wimp out and use writev(2).
         */
        if (trl_uio != NULL) {
                sbunlock(&so->so_snd);
                error = kern_writev(td, uap->s, trl_uio);
                if (error == 0)
                        sbytes += td->td_retval[0];
                goto out;
        }

done:
        sbunlock(&so->so_snd);
out:
        /*
         * If there was no error we have to clear td->td_retval[0]
         * because it may have been set by writev.
         */
        if (error == 0) {
                td->td_retval[0] = 0;
        }
        if (uap->sbytes != NULL) {
                copyout(&sbytes, uap->sbytes, sizeof(off_t));
        }
        if (obj != NULL)
                vm_object_deallocate(obj);
        if (vp != NULL) {
                vfslocked = VFS_LOCK_GIANT(vp->v_mount);
                vrele(vp);
                VFS_UNLOCK_GIANT(vfslocked);
        }
        if (so)
                fdrop(sock_fp, td);
        if (m)
                m_freem(m);

        if (sfs != NULL) {
                mtx_lock(&sfs->mtx);
                if (sfs->count != 0)
                        cv_wait(&sfs->cv, &sfs->mtx);
                KASSERT(sfs->count == 0, ("sendfile sync still busy"));
                cv_destroy(&sfs->cv);
                mtx_destroy(&sfs->mtx);
                free(sfs, M_TEMP);
        }

        if (error == ERESTART)
                error = EINTR;

        return (error);
}

/*
 * SCTP syscalls.
 * Functionality only compiled in if SCTP is defined in the kernel Makefile,
 * otherwise all return EOPNOTSUPP.
 * XXX: We should make this loadable one day.
 */
int
sys_sctp_peeloff(td, uap)
        struct thread *td;
        struct sctp_peeloff_args /* {
                int     sd;
                caddr_t name;
        } */ *uap;
{
#if (defined(INET) || defined(INET6)) && defined(SCTP)
        struct filedesc *fdp;
        struct file *nfp = NULL;
        int error;
        struct socket *head, *so;
        int fd;
        u_int fflag;

        fdp = td->td_proc->p_fd;
        AUDIT_ARG_FD(uap->sd);
        error = fgetsock(td, uap->sd, CAP_PEELOFF, &head, &fflag);
        if (error)
                goto done2;
        if (head->so_proto->pr_protocol != IPPROTO_SCTP) {
                error = EOPNOTSUPP;
                goto done;
        }
        error = sctp_can_peel_off(head, (sctp_assoc_t)uap->name);
        if (error)
                goto done;
        /*
         * At this point we know we do have a assoc to pull
         * we proceed to get the fd setup. This may block
         * but that is ok.
         */

        error = falloc(td, &nfp, &fd, 0);
        if (error)
                goto done;
        td->td_retval[0] = fd;

        CURVNET_SET(head->so_vnet);
        so = sonewconn(head, SS_ISCONNECTED);
        if (so == NULL) {
                error = ENOMEM;
                goto noconnection;
        }
        /*
         * Before changing the flags on the socket, we have to bump the
         * reference count.  Otherwise, if the protocol calls sofree(),
         * the socket will be released due to a zero refcount.
         */
        SOCK_LOCK(so);
        soref(so);                      /* file descriptor reference */
        SOCK_UNLOCK(so);

        ACCEPT_LOCK();

        TAILQ_REMOVE(&head->so_comp, so, so_list);
        head->so_qlen--;
        so->so_state |= (head->so_state & SS_NBIO);
        so->so_state &= ~SS_NOFDREF;
        so->so_qstate &= ~SQ_COMP;
        so->so_head = NULL;
        ACCEPT_UNLOCK();
        finit(nfp, fflag, DTYPE_SOCKET, so, &socketops);
        error = sctp_do_peeloff(head, so, (sctp_assoc_t)uap->name);
        if (error)
                goto noconnection;
        if (head->so_sigio != NULL)
                fsetown(fgetown(&head->so_sigio), &so->so_sigio);

noconnection:
        /*
         * close the new descriptor, assuming someone hasn't ripped it
         * out from under us.
         */
        if (error)
                fdclose(fdp, nfp, fd, td);

        /*
         * Release explicitly held references before returning.
         */
        CURVNET_RESTORE();
done:
        if (nfp != NULL)
                fdrop(nfp, td);
        fputsock(head);
done2:
        return (error);
#else  /* SCTP */
        return (EOPNOTSUPP);
#endif /* SCTP */
}

int
sys_sctp_generic_sendmsg (td, uap)
        struct thread *td;
        struct sctp_generic_sendmsg_args /* {
                int sd, 
                caddr_t msg, 
                int mlen, 
                caddr_t to, 
                __socklen_t tolen, 
                struct sctp_sndrcvinfo *sinfo, 
                int flags
        } */ *uap;
{
#if (defined(INET) || defined(INET6)) && defined(SCTP)
        struct sctp_sndrcvinfo sinfo, *u_sinfo = NULL;
        struct socket *so;
        struct file *fp = NULL;
        int error = 0, len;
        struct sockaddr *to = NULL;
#ifdef KTRACE
        struct uio *ktruio = NULL;
#endif
        struct uio auio;
        struct iovec iov[1];
        cap_rights_t rights;

        if (uap->sinfo) {
                error = copyin(uap->sinfo, &sinfo, sizeof (sinfo));
                if (error)
                        return (error);
                u_sinfo = &sinfo;
        }

        rights = CAP_WRITE;
        if (uap->tolen) {
                error = getsockaddr(&to, uap->to, uap->tolen);
                if (error) {
                        to = NULL;
                        goto sctp_bad2;
                }
                rights |= CAP_CONNECT;
        }

        AUDIT_ARG_FD(uap->sd);
        error = getsock_cap(td->td_proc->p_fd, uap->sd, rights, &fp, NULL);
        if (error)
                goto sctp_bad;
#ifdef KTRACE
        if (to && (KTRPOINT(td, KTR_STRUCT)))
                ktrsockaddr(to);
#endif

        iov[0].iov_base = uap->msg;
        iov[0].iov_len = uap->mlen;

        so = (struct socket *)fp->f_data;
        if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
                error = EOPNOTSUPP;
                goto sctp_bad;
        }
#ifdef MAC
        error = mac_socket_check_send(td->td_ucred, so);
        if (error)
                goto sctp_bad;
#endif /* MAC */

        auio.uio_iov =  iov;
        auio.uio_iovcnt = 1;
        auio.uio_segflg = UIO_USERSPACE;
        auio.uio_rw = UIO_WRITE;
        auio.uio_td = td;
        auio.uio_offset = 0;                    /* XXX */
        auio.uio_resid = 0;
        len = auio.uio_resid = uap->mlen;
        CURVNET_SET(so->so_vnet);
        error = sctp_lower_sosend(so, to, &auio,
                    (struct mbuf *)NULL, (struct mbuf *)NULL,
                    uap->flags, u_sinfo, td);
        CURVNET_RESTORE();
        if (error) {
                if (auio.uio_resid != len && (error == ERESTART ||
                    error == EINTR || error == EWOULDBLOCK))
                        error = 0;
                /* Generation of SIGPIPE can be controlled per socket. */
                if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
                    !(uap->flags & MSG_NOSIGNAL)) {
                        PROC_LOCK(td->td_proc);
                        tdsignal(td, SIGPIPE);
                        PROC_UNLOCK(td->td_proc);
                }
        }
        if (error == 0)
                td->td_retval[0] = len - auio.uio_resid;
#ifdef KTRACE
        if (ktruio != NULL) {
                ktruio->uio_resid = td->td_retval[0];
                ktrgenio(uap->sd, UIO_WRITE, ktruio, error);
        }
#endif /* KTRACE */
sctp_bad:
        if (fp)
                fdrop(fp, td);
sctp_bad2:
        if (to)
                free(to, M_SONAME);
        return (error);
#else  /* SCTP */
        return (EOPNOTSUPP);
#endif /* SCTP */
}

int
sys_sctp_generic_sendmsg_iov(td, uap)
        struct thread *td;
        struct sctp_generic_sendmsg_iov_args /* {
                int sd, 
                struct iovec *iov, 
                int iovlen, 
                caddr_t to, 
                __socklen_t tolen, 
                struct sctp_sndrcvinfo *sinfo, 
                int flags
        } */ *uap;
{
#if (defined(INET) || defined(INET6)) && defined(SCTP)
        struct sctp_sndrcvinfo sinfo, *u_sinfo = NULL;
        struct socket *so;
        struct file *fp = NULL;
        int error=0, i;
        ssize_t len;
        struct sockaddr *to = NULL;
#ifdef KTRACE
        struct uio *ktruio = NULL;
#endif
        struct uio auio;
        struct iovec *iov, *tiov;
        cap_rights_t rights;

        if (uap->sinfo) {
                error = copyin(uap->sinfo, &sinfo, sizeof (sinfo));
                if (error)
                        return (error);
                u_sinfo = &sinfo;
        }
        rights = CAP_WRITE;
        if (uap->tolen) {
                error = getsockaddr(&to, uap->to, uap->tolen);
                if (error) {
                        to = NULL;
                        goto sctp_bad2;
                }
                rights |= CAP_CONNECT;
        }

        AUDIT_ARG_FD(uap->sd);
        error = getsock_cap(td->td_proc->p_fd, uap->sd, rights, &fp, NULL);
        if (error)
                goto sctp_bad1;

#ifdef COMPAT_32BIT
        if (SV_CURPROC_FLAG(SV_ILP32))
                error = compat32bit_copyiniov((struct iovec32 *)uap->iov,
                    uap->iovlen, &iov, EMSGSIZE);
        else
#endif
                error = copyiniov(uap->iov, uap->iovlen, &iov, EMSGSIZE);
        if (error)
                goto sctp_bad1;
#ifdef KTRACE
        if (to && (KTRPOINT(td, KTR_STRUCT)))
                ktrsockaddr(to);
#endif

        so = (struct socket *)fp->f_data;
        if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
                error = EOPNOTSUPP;
                goto sctp_bad;
        }
#ifdef MAC
        error = mac_socket_check_send(td->td_ucred, so);
        if (error)
                goto sctp_bad;
#endif /* MAC */

        auio.uio_iov = iov;
        auio.uio_iovcnt = uap->iovlen;
        auio.uio_segflg = UIO_USERSPACE;
        auio.uio_rw = UIO_WRITE;
        auio.uio_td = td;
        auio.uio_offset = 0;                    /* XXX */
        auio.uio_resid = 0;
        tiov = iov;
        for (i = 0; i <uap->iovlen; i++, tiov++) {
                if ((auio.uio_resid += tiov->iov_len) < 0) {
                        error = EINVAL;
                        goto sctp_bad;
                }
        }
        len = auio.uio_resid;
        CURVNET_SET(so->so_vnet);
        error = sctp_lower_sosend(so, to, &auio,
                    (struct mbuf *)NULL, (struct mbuf *)NULL,
                    uap->flags, u_sinfo, td);
        CURVNET_RESTORE();
        if (error) {
                if (auio.uio_resid != len && (error == ERESTART ||
                    error == EINTR || error == EWOULDBLOCK))
                        error = 0;
                /* Generation of SIGPIPE can be controlled per socket */
                if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
                    !(uap->flags & MSG_NOSIGNAL)) {
                        PROC_LOCK(td->td_proc);
                        tdsignal(td, SIGPIPE);
                        PROC_UNLOCK(td->td_proc);
                }
        }
        if (error == 0)
                td->td_retval[0] = len - auio.uio_resid;
#ifdef KTRACE
        if (ktruio != NULL) {
                ktruio->uio_resid = td->td_retval[0];
                ktrgenio(uap->sd, UIO_WRITE, ktruio, error);
        }
#endif /* KTRACE */
sctp_bad:
        free(iov, M_IOV);
sctp_bad1:
        if (fp)
                fdrop(fp, td);
sctp_bad2:
        if (to)
                free(to, M_SONAME);
        return (error);
#else  /* SCTP */
        return (EOPNOTSUPP);
#endif /* SCTP */
}

int
sys_sctp_generic_recvmsg(td, uap)
        struct thread *td;
        struct sctp_generic_recvmsg_args /* {
                int sd, 
                struct iovec *iov, 
                int iovlen,
                struct sockaddr *from, 
                __socklen_t *fromlenaddr,
                struct sctp_sndrcvinfo *sinfo, 
                int *msg_flags
        } */ *uap;
{
#if (defined(INET) || defined(INET6)) && defined(SCTP)
        uint8_t sockbufstore[256];
        struct uio auio;
        struct iovec *iov, *tiov;
        struct sctp_sndrcvinfo sinfo;
        struct socket *so;
        struct file *fp = NULL;
        struct sockaddr *fromsa;
        int fromlen;
        ssize_t len;
        int i, msg_flags;
        int error = 0;
#ifdef KTRACE
        struct uio *ktruio = NULL;
#endif

        AUDIT_ARG_FD(uap->sd);
        error = getsock_cap(td->td_proc->p_fd, uap->sd, CAP_READ, &fp, NULL);
        if (error) {
                return (error);
        }
#ifdef COMPAT_32BIT
        if (SV_CURPROC_FLAG(SV_ILP32))
                error = compat32bit_copyiniov((struct iovec32 *)uap->iov,
                    uap->iovlen, &iov, EMSGSIZE);
        else
#endif
                error = copyiniov(uap->iov, uap->iovlen, &iov, EMSGSIZE);
        if (error)
                goto out1;

        so = fp->f_data;
        if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
                error = EOPNOTSUPP;
                goto out;
        }
#ifdef MAC
        error = mac_socket_check_receive(td->td_ucred, so);
        if (error) {
                goto out;
        }
#endif /* MAC */

        if (uap->fromlenaddr) {
                error = copyin(uap->fromlenaddr,
                    &fromlen, sizeof (fromlen));
                if (error) {
                        goto out;
                }
        } else {
                fromlen = 0;
        }
        if (uap->msg_flags) {
                error = copyin(uap->msg_flags, &msg_flags, sizeof (int));
                if (error) {
                        goto out;
                }
        } else {
                msg_flags = 0;
        }
        auio.uio_iov = iov;
        auio.uio_iovcnt = uap->iovlen;
        auio.uio_segflg = UIO_USERSPACE;
        auio.uio_rw = UIO_READ;
        auio.uio_td = td;
        auio.uio_offset = 0;                    /* XXX */
        auio.uio_resid = 0;
        tiov = iov;
        for (i = 0; i <uap->iovlen; i++, tiov++) {
                if ((auio.uio_resid += tiov->iov_len) < 0) {
                        error = EINVAL;
                        goto out;
                }
        }
        len = auio.uio_resid;
        fromsa = (struct sockaddr *)sockbufstore;

#ifdef KTRACE
        if (KTRPOINT(td, KTR_GENIO))
                ktruio = cloneuio(&auio);
#endif /* KTRACE */
        memset(&sinfo, 0, sizeof(struct sctp_sndrcvinfo));
        CURVNET_SET(so->so_vnet);
        error = sctp_sorecvmsg(so, &auio, (struct mbuf **)NULL,
                    fromsa, fromlen, &msg_flags,
                    (struct sctp_sndrcvinfo *)&sinfo, 1);
        CURVNET_RESTORE();
        if (error) {
                if (auio.uio_resid != len && (error == ERESTART ||
                    error == EINTR || error == EWOULDBLOCK))
                        error = 0;
        } else {
                if (uap->sinfo)
                        error = copyout(&sinfo, uap->sinfo, sizeof (sinfo));
        }
#ifdef KTRACE
        if (ktruio != NULL) {
                ktruio->uio_resid = len - auio.uio_resid;
                ktrgenio(uap->sd, UIO_READ, ktruio, error);
        }
#endif /* KTRACE */
        if (error)
                goto out;
        td->td_retval[0] = len - auio.uio_resid;

        if (fromlen && uap->from) {
                len = fromlen;
                if (len <= 0 || fromsa == 0)
                        len = 0;
                else {
                        len = MIN(len, fromsa->sa_len);
                        error = copyout(fromsa, uap->from, (size_t)len);
                        if (error)
                                goto out;
                }
                error = copyout(&len, uap->fromlenaddr, sizeof (socklen_t));
                if (error) {
                        goto out;
                }
        }
#ifdef KTRACE
        if (KTRPOINT(td, KTR_STRUCT))
                ktrsockaddr(fromsa);
#endif
        if (uap->msg_flags) {
                error = copyout(&msg_flags, uap->msg_flags, sizeof (int));
                if (error) {
                        goto out;
                }
        }
out:
        free(iov, M_IOV);
out1:
        if (fp) 
                fdrop(fp, td);

        return (error);
#else  /* SCTP */
        return (EOPNOTSUPP);
#endif /* SCTP */
}