/*
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rick Macklem at The University of Guelph.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)nfs_syscalls.c      8.5 (Berkeley) 3/30/95
 * $FreeBSD: src/sys/nfs/nfs_syscalls.c,v 1.58.2.1 2000/11/26 02:30:06 dillon Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysmsg.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/file.h>
#include <sys/filedesc.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/caps.h>
#include <sys/buf.h>
#include <sys/mbuf.h>
#include <sys/resourcevar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/nlookup.h>

#include <sys/mutex2.h>
#include <sys/thread2.h>

#include <netinet/in.h>
#include <netinet/tcp.h>
#include "xdr_subs.h"
#include "rpcv2.h"
#include "nfsproto.h"
#include "nfs.h"
#include "nfsm_subs.h"
#include "nfsrvcache.h"
#include "nfsmount.h"
#include "nfsnode.h"
#include "nfsrtt.h"

static MALLOC_DEFINE(M_NFSSVC, "NFS srvsock", "Nfs server structure");

static int nuidhash_max = NFS_MAXUIDHASH;

#ifndef NFS_NOSERVER
static void     nfsrv_zapsock (struct nfssvc_sock *slp);
#endif

#define TRUE    1
#define FALSE   0

SYSCTL_DECL(_vfs_nfs);

#ifndef NFS_NOSERVER
int nfsd_waiting = 0;
static struct nfsdrt nfsdrt;
static int nfs_numnfsd = 0;
static void     nfsd_rt (int sotype, struct nfsrv_descript *nd,
                             int cacherep);
static int      nfssvc_addsock (struct file *, struct sockaddr *,
                                    struct thread *);
static int      nfssvc_nfsd (struct nfsd_srvargs *,caddr_t,struct thread *);

static int nfs_privport = 0;
SYSCTL_INT(_vfs_nfs, NFS_NFSPRIVPORT, nfs_privport, CTLFLAG_RW, &nfs_privport,
    0, "Enable privileged source port checks");
SYSCTL_INT(_vfs_nfs, OID_AUTO, gatherdelay, CTLFLAG_RW, &nfsrvw_procrastinate, 0,
    "Enable NFS request procrastination");
SYSCTL_INT(_vfs_nfs, OID_AUTO, gatherdelay_v3, CTLFLAG_RW, &nfsrvw_procrastinate_v3, 0,
    "Enable NFSv3 request procrastination");
int     nfs_soreserve = NFS_MAXPACKET * NFS_MAXASYNCBIO;
SYSCTL_INT(_vfs_nfs, OID_AUTO, soreserve, CTLFLAG_RW, &nfs_soreserve, 0,
    "Minimum NFS socket buffer size reservation");

/*
 * NFS server system calls
 */

#endif /* NFS_NOSERVER */
/*
 * nfssvc_args(int flag, caddr_t argp)
 *
 * Nfs server psuedo system call for the nfsd's
 * Based on the flag value it either:
 * - adds a socket to the selection list
 * - remains in the kernel as an nfsd
 * - remains in the kernel as an nfsiod
 *
 * MPALMOSTSAFE
 */
int
sys_nfssvc(struct sysmsg *sysmsg, const struct nfssvc_args *uap)
{
#ifndef NFS_NOSERVER
        struct nlookupdata nd;
        struct file *fp;
        struct sockaddr *nam;
        struct nfsd_args nfsdarg;
        struct nfsd_srvargs nfsd_srvargs, *nsd = &nfsd_srvargs;
        struct nfsd_cargs ncd;
        struct nfsd *nfsd;
        struct nfssvc_sock *slp;
        struct nfsuid *nuidp;
        struct nfsmount *nmp;
        struct vnode *vp;
#endif /* NFS_NOSERVER */
        int error;
        struct thread *td = curthread;

        /*
         * Must be super user
         */
        error = caps_priv_check_td(td, SYSCAP_RESTRICTEDROOT);
        if (error)
                return (error);

        lwkt_gettoken(&nfs_token);

        while (nfssvc_sockhead_flag & SLP_INIT) {
                nfssvc_sockhead_flag |= SLP_WANTINIT;
                tsleep((caddr_t)&nfssvc_sockhead, 0, "nfsd init", 0);
        }
        if (uap->flag & NFSSVC_BIOD)
                error = ENXIO;          /* no longer need nfsiod's */
#ifdef NFS_NOSERVER
        else
                error = ENXIO;
#else /* !NFS_NOSERVER */
        else if (uap->flag & NFSSVC_MNTD) {
                error = copyin(uap->argp, (caddr_t)&ncd, sizeof (ncd));
                if (error)
                        goto done;
                vp = NULL;
                error = nlookup_init(&nd, ncd.ncd_dirp, UIO_USERSPACE,
                                        NLC_FOLLOW);
                if (error == 0)
                        error = nlookup(&nd);
                if (error == 0)
                        error = cache_vget(&nd.nl_nch, nd.nl_cred, LK_EXCLUSIVE, &vp);
                nlookup_done(&nd);
                if (error)
                        goto done;

                if ((vp->v_flag & VROOT) == 0)
                        error = EINVAL;
                nmp = VFSTONFS(vp->v_mount);
                vput(vp);
                if (error)
                        goto done;
                if ((nmp->nm_state & NFSSTA_MNTD) &&
                        (uap->flag & NFSSVC_GOTAUTH) == 0) {
                        error = 0;
                        goto done;
                }
                nmp->nm_state |= NFSSTA_MNTD;
                error = nfs_clientd(nmp, td->td_ucred, &ncd, uap->flag,
                                    uap->argp, td);
        } else if (uap->flag & NFSSVC_ADDSOCK) {
                error = copyin(uap->argp, (caddr_t)&nfsdarg, sizeof(nfsdarg));
                if (error)
                        goto done;
                error = holdsock(td, nfsdarg.sock, &fp);
                if (error)
                        goto done;
                /*
                 * Get the client address for connected sockets.
                 */
                if (nfsdarg.name == NULL || nfsdarg.namelen == 0)
                        nam = NULL;
                else {
                        error = getsockaddr(&nam, nfsdarg.name,
                                            nfsdarg.namelen);
                        if (error) {
                                fdrop(fp);
                                goto done;
                        }
                }
                error = nfssvc_addsock(fp, nam, td);
                fdrop(fp);
        } else {
                error = copyin(uap->argp, (caddr_t)nsd, sizeof (*nsd));
                if (error)
                        goto done;
                if ((uap->flag & NFSSVC_AUTHIN) &&
                    ((nfsd = nsd->nsd_nfsd)) != NULL &&
                    (nfsd->nfsd_slp->ns_flag & SLP_VALID)) {
                        slp = nfsd->nfsd_slp;

                        /*
                         * First check to see if another nfsd has already
                         * added this credential.
                         */
                        for (nuidp = NUIDHASH(slp,nsd->nsd_cr.cr_uid)->lh_first;
                            nuidp != 0; nuidp = nuidp->nu_hash.le_next) {
                                if (nuidp->nu_cr.cr_uid == nsd->nsd_cr.cr_uid &&
                                    (!nfsd->nfsd_nd->nd_nam2 ||
                                     netaddr_match(AF_INET,
                                     &nuidp->nu_haddr, nfsd->nfsd_nd->nd_nam2)))
                                        break;
                        }
                        if (nuidp) {
                            nfsrv_setcred(&nuidp->nu_cr,&nfsd->nfsd_nd->nd_cr);
                            nfsd->nfsd_nd->nd_flag |= ND_KERBFULL;
                        } else {
                            /*
                             * Nope, so we will.
                             */
                            if (slp->ns_numuids < nuidhash_max) {
                                slp->ns_numuids++;
                                nuidp = (struct nfsuid *)
                                   kmalloc(sizeof (struct nfsuid), M_NFSUID,
                                        M_WAITOK);
                            } else
                                nuidp = NULL;
                            if ((slp->ns_flag & SLP_VALID) == 0) {
                                if (nuidp)
                                    kfree((caddr_t)nuidp, M_NFSUID);
                            } else {
                                if (nuidp == NULL) {
                                    nuidp = TAILQ_FIRST(&slp->ns_uidlruhead);
                                    LIST_REMOVE(nuidp, nu_hash);
                                    TAILQ_REMOVE(&slp->ns_uidlruhead, nuidp,
                                        nu_lru);
                                    if (nuidp->nu_flag & NU_NAM)
                                        kfree(nuidp->nu_nam, M_SONAME);
                                }
                                nuidp->nu_flag = 0;
                                nuidp->nu_cr = nsd->nsd_cr;
                                if (nuidp->nu_cr.cr_ngroups > NGROUPS)
                                    nuidp->nu_cr.cr_ngroups = NGROUPS;
                                nuidp->nu_cr.cr_ref = 1;
                                nuidp->nu_timestamp = nsd->nsd_timestamp;
                                nuidp->nu_expire = time_uptime + nsd->nsd_ttl;
                                /*
                                 * and save the session key in nu_key.
                                 */
                                bcopy(nsd->nsd_key, nuidp->nu_key,
                                    sizeof (nsd->nsd_key));
                                if (nfsd->nfsd_nd->nd_nam2) {
                                    struct sockaddr_in *saddr;

                                    saddr = (struct sockaddr_in *)
                                            nfsd->nfsd_nd->nd_nam2;
                                    switch (saddr->sin_family) {
                                    case AF_INET:
                                        nuidp->nu_flag |= NU_INETADDR;
                                        nuidp->nu_inetaddr =
                                             saddr->sin_addr.s_addr;
                                        break;
                                    default:
                                        nuidp->nu_flag |= NU_NAM;
                                        nuidp->nu_nam =
                                          dup_sockaddr(nfsd->nfsd_nd->nd_nam2);
                                        break;
                                    };
                                }
                                TAILQ_INSERT_TAIL(&slp->ns_uidlruhead, nuidp,
                                        nu_lru);
                                LIST_INSERT_HEAD(NUIDHASH(slp, nsd->nsd_uid),
                                        nuidp, nu_hash);
                                nfsrv_setcred(&nuidp->nu_cr,
                                    &nfsd->nfsd_nd->nd_cr);
                                nfsd->nfsd_nd->nd_flag |= ND_KERBFULL;
                            }
                        }
                }
                if ((uap->flag & NFSSVC_AUTHINFAIL) && (nfsd = nsd->nsd_nfsd))
                        nfsd->nfsd_flag |= NFSD_AUTHFAIL;
                error = nfssvc_nfsd(nsd, uap->argp, td);
        }
#endif /* NFS_NOSERVER */
        if (error == EINTR || error == ERESTART)
                error = 0;
done:
        lwkt_reltoken(&nfs_token);
        return (error);
}

#ifndef NFS_NOSERVER
/*
 * Adds a socket to the list for servicing by nfsds.
 */
static int
nfssvc_addsock(struct file *fp, struct sockaddr *mynam, struct thread *td)
{
        int siz;
        struct nfssvc_sock *slp;
        struct socket *so;
        int error;

        so = (struct socket *)fp->f_data;
#if 0
        tslp = NULL;
        /*
         * Add it to the list, as required.
         */
        if (so->so_proto->pr_protocol == IPPROTO_UDP) {
                tslp = nfs_udpsock;
                if (tslp->ns_flag & SLP_VALID) {
                        if (mynam != NULL)
                                kfree(mynam, M_SONAME);
                        return (EPERM);
                }
        }
#endif
        /*
         * Reserve buffer space in the socket.  Note that due to bugs in
         * Linux's delayed-ack code, serious performance degredation may
         * occur with linux hosts if the minimum is used.
         *
         * NFS sockets are not limited to the standard sb_max or by
         * resource limits.
         */
        if (so->so_type == SOCK_STREAM)
                siz = NFS_MAXPACKET + sizeof (u_long);
        else
                siz = NFS_MAXPACKET;
        if (siz < nfs_soreserve)
            siz = nfs_soreserve;

        error = soreserve(so, siz, siz, NULL);
        if (error) {
                if (mynam != NULL)
                        kfree(mynam, M_SONAME);
                return (error);
        }

        /*
         * Set protocol specific options { for now TCP only } and
         * reserve some space. For datagram sockets, this can get called
         * repeatedly for the same socket, but that isn't harmful.
         */
        if (so->so_type == SOCK_STREAM) {
                struct sockopt sopt;
                int val;

                bzero(&sopt, sizeof sopt);
                sopt.sopt_level = SOL_SOCKET;
                sopt.sopt_name = SO_KEEPALIVE;
                sopt.sopt_val = &val;
                sopt.sopt_valsize = sizeof val;
                val = 1;
                sosetopt(so, &sopt);
        }
        if (so->so_proto->pr_domain->dom_family == AF_INET &&
            so->so_proto->pr_protocol == IPPROTO_TCP) {
                struct sockopt sopt;
                int val;

                bzero(&sopt, sizeof sopt);
                sopt.sopt_level = IPPROTO_TCP;
                sopt.sopt_name = TCP_NODELAY;
                sopt.sopt_val = &val;
                sopt.sopt_valsize = sizeof val;
                val = 1;
                sosetopt(so, &sopt);

                bzero(&sopt, sizeof sopt);
                sopt.sopt_level = IPPROTO_TCP;
                sopt.sopt_name = TCP_FASTKEEP;
                sopt.sopt_val = &val;
                sopt.sopt_valsize = sizeof val;
                val = 1;
                sosetopt(so, &sopt);
        }
        atomic_clear_int(&so->so_rcv.ssb_flags, SSB_NOINTR);
        so->so_rcv.ssb_timeo = 0;
        atomic_clear_int(&so->so_snd.ssb_flags, SSB_NOINTR);
        so->so_snd.ssb_timeo = 0;

        /*
         * Clear AUTOSIZE, otherwise the socket buffer could be reduced
         * to the point where rpc's cannot be queued using the mbuf
         * interface.
         */
        atomic_clear_int(&so->so_rcv.ssb_flags, SSB_AUTOSIZE);
        atomic_clear_int(&so->so_snd.ssb_flags, SSB_AUTOSIZE);

        slp = kmalloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK | M_ZERO);
        mtx_init(&slp->ns_solock, "nfsvc");
        STAILQ_INIT(&slp->ns_rec);
        TAILQ_INIT(&slp->ns_uidlruhead);
        lwkt_token_init(&slp->ns_token, "nfssrv_token");

        lwkt_gettoken(&nfs_token);
        nfsrv_slpref(slp);
        TAILQ_INSERT_TAIL(&nfssvc_sockhead, slp, ns_chain);
        lwkt_gettoken(&slp->ns_token);

        slp->ns_so = so;
        slp->ns_nam = mynam;
        fhold(fp);
        slp->ns_fp = fp;

        so->so_upcallarg = (caddr_t)slp;
        so->so_upcall = nfsrv_rcv_upcall;
        atomic_set_int(&so->so_rcv.ssb_flags, SSB_UPCALL);
        slp->ns_flag = (SLP_VALID | SLP_NEEDQ);
        nfsrv_wakenfsd(slp, 1);

        lwkt_reltoken(&slp->ns_token);
        lwkt_reltoken(&nfs_token);

        return (0);
}

/*
 * Called by nfssvc() for nfsds. Just loops around servicing rpc requests
 * until it is killed by a signal.
 */
static int
nfssvc_nfsd(struct nfsd_srvargs *nsd, caddr_t argp, struct thread *td)
{
        int siz;
        struct nfssvc_sock *slp;
        struct nfsd *nfsd = nsd->nsd_nfsd;
        struct nfsrv_descript *nd = NULL;
        struct mbuf *m, *mreq;
        int error, cacherep, sotype, writes_todo;
        int procrastinate;
        int slplocked;
        u_quad_t cur_usec;

#ifndef nolint
        cacherep = RC_DOIT;
        writes_todo = 0;
#endif
        lwkt_gettoken(&nfs_token);

        if (nfsd == NULL) {
                nsd->nsd_nfsd = nfsd = (struct nfsd *)
                        kmalloc(sizeof (struct nfsd), M_NFSD, M_WAITOK|M_ZERO);
                nfsd->nfsd_td = td;
                TAILQ_INSERT_TAIL(&nfsd_head, nfsd, nfsd_chain);
                nfs_numnfsd++;
        }

        /*
         * Loop getting rpc requests until SIGKILL.
         */
        for (;;) {
                if ((nfsd->nfsd_flag & NFSD_REQINPROG) == 0) {
                        while (nfsd->nfsd_slp == NULL &&
                            (nfsd_head_flag & NFSD_CHECKSLP) == 0) {
                                nfsd->nfsd_flag |= NFSD_WAITING;
                                nfsd_waiting++;
                                error = tsleep(nfsd, PCATCH, "nfsd", 0);
                                nfsd_waiting--;
                                if (error && nfsd->nfsd_slp == NULL)
                                        goto done;
                        }
                        if (nfsd->nfsd_slp == NULL &&
                            (nfsd_head_flag & NFSD_CHECKSLP)) {
                                TAILQ_FOREACH(slp, &nfssvc_sockhead, ns_chain) {
                                    if ((slp->ns_flag & SLP_ACTION_MASK) ||
                                        slp->ns_needq_upcall) {
                                            nfsrv_slpref(slp);
                                            nfsd->nfsd_slp = slp;
                                            break;
                                    }
                                }
                                if (slp == NULL)
                                        nfsd_head_flag &= ~NFSD_CHECKSLP;
                        }
                        if ((slp = nfsd->nfsd_slp) == NULL)
                                continue;

                        lwkt_reltoken(&nfs_token);
                        lwkt_gettoken(&slp->ns_token);

                        if (slp->ns_needq_upcall) {
                                slp->ns_needq_upcall = 0;
                                slp->ns_flag |= SLP_NEEDQ;
                        }

                        if (slp->ns_flag & SLP_VALID) {
                                /*
                                 * We can both process additional received
                                 * data into new records and process existing
                                 * records.  This keeps the pipeline hot by
                                 * allowing the tcp socket to continue to
                                 * drain while we are processing records.
                                 */
                                while (slp->ns_flag & (SLP_DISCONN|SLP_NEEDQ)) {
                                        if (slp->ns_flag & SLP_DISCONN) {
                                                nfsrv_zapsock(slp);
                                                break;
                                        }
                                        if (slp->ns_flag & SLP_NEEDQ) {
                                                nfs_slplock(slp, 1);
                                                if ((slp->ns_flag &
                                                     SLP_NEEDQ) == 0) {
                                                        nfs_slpunlock(slp);
                                                        continue;
                                                }
                                                nfsrv_rcv(slp->ns_so,
                                                          (caddr_t)slp,
                                                          M_WAITOK);
                                                nfs_slpunlock(slp);
                                                break;
                                        }
                                }
                                error = nfsrv_dorec(slp, nfsd, &nd);
                                cur_usec = nfs_curusec();
                                if (error && slp->ns_tq.lh_first &&
                                    slp->ns_tq.lh_first->nd_time <= cur_usec) {
                                        error = 0;
                                        cacherep = RC_DOIT;
                                        writes_todo = 1;
                                } else {
                                        writes_todo = 0;
                                }
                                nfsd->nfsd_flag |= NFSD_REQINPROG;
                        } else {
                                slp->ns_flag &= ~SLP_ACTION_MASK;
                                error = 0;
                        }
                } else {
                        error = 0;
                        slp = nfsd->nfsd_slp;

                        lwkt_reltoken(&nfs_token);
                        lwkt_gettoken(&slp->ns_token);

                        if (slp->ns_needq_upcall) {
                                slp->ns_needq_upcall = 0;
                                slp->ns_flag |= SLP_NEEDQ;
                        }
                        if (NFSRV_RECLIMIT(slp) == 0 &&
                            (slp->ns_flag & SLP_NEEDQ)) {
                                nfs_slplock(slp, 1);
                                if (NFSRV_RECLIMIT(slp) == 0 &&
                                    (slp->ns_flag & SLP_NEEDQ)) {
                                        nfsrv_rcv(slp->ns_so, (caddr_t)slp,
                                                  M_WAITOK);
                                }
                                nfs_slpunlock(slp);
                        }
                }

                /*
                 * nfs_token not held here.  slp token is held.
                 */
                if (error || (slp->ns_flag & SLP_VALID) == 0) {
                        if (nd) {
                                kfree((caddr_t)nd, M_NFSRVDESC);
                                nd = NULL;
                        }
                        nfsd->nfsd_flag &= ~NFSD_REQINPROG;
                        if (slp->ns_flag & SLP_ACTION_MASK) {
                                lwkt_reltoken(&slp->ns_token);
                                lwkt_gettoken(&nfs_token);
                        } else {
                                nfsd->nfsd_slp = NULL;
                                lwkt_reltoken(&slp->ns_token);
                                lwkt_gettoken(&nfs_token);
                                nfsrv_slpderef(slp);
                        }
                        continue;
                }
                sotype = slp->ns_so->so_type;

                /*
                 * Execute the NFS request - handle the server side cache
                 *
                 * nfs_token not held here.  slp token is held.
                 */
                if (nd) {
                    getmicrotime(&nd->nd_starttime);
                    if (nd->nd_nam2)
                        nd->nd_nam = nd->nd_nam2;
                    else
                        nd->nd_nam = slp->ns_nam;

                    /*
                     * Check to see if authorization is needed.
                     */
                    if (nfsd->nfsd_flag & NFSD_NEEDAUTH) {
                        nfsd->nfsd_flag &= ~NFSD_NEEDAUTH;
                        nsd->nsd_haddr =
                                ((struct sockaddr_in *)
                                 nd->nd_nam)->sin_addr.s_addr;
                        nsd->nsd_authlen = nfsd->nfsd_authlen;
                        nsd->nsd_verflen = nfsd->nfsd_verflen;
                        if (!copyout(nfsd->nfsd_authstr,nsd->nsd_authstr,
                                nfsd->nfsd_authlen) &&
                            !copyout(nfsd->nfsd_verfstr, nsd->nsd_verfstr,
                                nfsd->nfsd_verflen) &&
                            !copyout((caddr_t)nsd, argp, sizeof (*nsd)))
                        {
                            lwkt_reltoken(&slp->ns_token);
                            return (ENEEDAUTH);
                        }
                        cacherep = RC_DROPIT;
                    } else {
                        cacherep = nfsrv_getcache(nd, slp, &mreq);
                    }

                    if (nfsd->nfsd_flag & NFSD_AUTHFAIL) {
                        nfsd->nfsd_flag &= ~NFSD_AUTHFAIL;
                        nd->nd_procnum = NFSPROC_NOOP;
                        nd->nd_repstat = (NFSERR_AUTHERR | AUTH_TOOWEAK);
                        cacherep = RC_DOIT;
                    } else if (nfs_privport) {
                        /* Check if source port is privileged */
                        u_short port;
                        struct sockaddr *nam = nd->nd_nam;
                        struct sockaddr_in *sin;

                        sin = (struct sockaddr_in *)nam;
                        port = ntohs(sin->sin_port);
                        if (port >= IPPORT_RESERVED &&
                            nd->nd_procnum != NFSPROC_NULL) {
                            char addr[INET_ADDRSTRLEN];

                            nd->nd_procnum = NFSPROC_NOOP;
                            nd->nd_repstat = (NFSERR_AUTHERR | AUTH_TOOWEAK);
                            cacherep = RC_DOIT;
                            kprintf("NFS request from unprivileged port (%s:%d)\n",
                                    kinet_ntoa(sin->sin_addr, addr), port);
                        }
                    }
                }

                /*
                 * Execute the NFS request - direct execution
                 *
                 * Loop to get all the write rpc replies that have been
                 * gathered together.
                 *
                 * nfs_token not held here.  slp token is held.
                 */
                do {
                    switch (cacherep) {
                    case RC_DOIT:
                        if (nd && (nd->nd_flag & ND_NFSV3))
                            procrastinate = nfsrvw_procrastinate_v3;
                        else
                            procrastinate = nfsrvw_procrastinate;
                        if (writes_todo || (nd->nd_procnum == NFSPROC_WRITE &&
                            procrastinate > 0)
                        ) {
                            error = nfsrv_writegather(&nd, slp,
                                                      nfsd->nfsd_td, &mreq);
                        } else {
                            /* NOT YET lwkt_reltoken(&slp->ns_token); */
                            error = (*(nfsrv3_procs[nd->nd_procnum]))(nd,
                                                slp, nfsd->nfsd_td, &mreq);
                            /* NOT YET lwkt_gettoken(&slp->ns_token); */
                            lwpkthreaddeferred();       /* vnlru issues */
                        }
                        if (mreq == NULL)
                                break;
                        if (error != 0 && error != NFSERR_RETVOID) {
                                if (nd->nd_procnum != NQNFSPROC_VACATED)
                                        nfsstats.srv_errs++;
                                nfsrv_updatecache(nd, FALSE, mreq);
                                if (nd->nd_nam2)
                                        kfree(nd->nd_nam2, M_SONAME);
                                break;
                        }
                        nfsstats.srvrpccnt[nd->nd_procnum]++;
                        nfsrv_updatecache(nd, TRUE, mreq);
                        nd->nd_mrep = NULL;
                        /* FALL THROUGH */
                    case RC_REPLY:
                        m = mreq;
                        siz = 0;
                        while (m) {
                                siz += m->m_len;
                                m = m->m_next;
                        }
                        if (siz <= 0 || siz > NFS_MAXPACKET) {
                                kprintf("mbuf siz=%d\n",siz);
                                panic("Bad nfs svc reply");
                        }
                        m = mreq;
                        m->m_pkthdr.len = siz;
                        m->m_pkthdr.rcvif = NULL;
                        /*
                         * For stream protocols, prepend a Sun RPC
                         * Record Mark.
                         */
                        if (sotype == SOCK_STREAM) {
                                M_PREPEND(m, NFSX_UNSIGNED, M_WAITOK);
                                *mtod(m, u_int32_t *) = htonl(0x80000000 | siz);
                        }
                        if ((slp->ns_flag & SLP_VALID) &&
                            (slp->ns_so->so_proto->pr_flags & PR_CONNREQUIRED)){
                                nfs_slplock(slp, 1);
                                slplocked = 1;
                        } else {
                                slplocked = 0;
                        }
                        if (slp->ns_flag & SLP_VALID) {
                            error = nfs_send(slp->ns_so, nd->nd_nam2, m, NULL);
                        } else {
                            error = EPIPE;
                            m_freem(m);
                        }
                        if (nfsrtton)
                                nfsd_rt(sotype, nd, cacherep);
                        if (nd->nd_nam2)
                                kfree(nd->nd_nam2, M_SONAME);
                        if (nd->nd_mrep)
                                m_freem(nd->nd_mrep);
                        if (error == EPIPE || error == ENOBUFS)
                                nfsrv_zapsock(slp);
                        if (slplocked)
                                nfs_slpunlock(slp);
                        if (error == EINTR || error == ERESTART) {
                                kfree((caddr_t)nd, M_NFSRVDESC);
                                lwkt_reltoken(&slp->ns_token);
                                lwkt_gettoken(&nfs_token);
                                nfsd->nfsd_slp = NULL;
                                nfsrv_slpderef(slp);
                                goto done;
                        }
                        break;
                    case RC_DROPIT:
                        if (nfsrtton)
                                nfsd_rt(sotype, nd, cacherep);
                        m_freem(nd->nd_mrep);
                        if (nd->nd_nam2)
                                kfree(nd->nd_nam2, M_SONAME);
                        break;
                    }
                    if (nd) {
                        kfree((caddr_t)nd, M_NFSRVDESC);
                        nd = NULL;
                    }

                    /*
                     * Check to see if there are outstanding writes that
                     * need to be serviced.
                     */
                    cur_usec = nfs_curusec();
                    if (slp->ns_tq.lh_first &&
                        slp->ns_tq.lh_first->nd_time <= cur_usec) {
                        cacherep = RC_DOIT;
                        writes_todo = 1;
                    } else {
                        writes_todo = 0;
                    }
                } while (writes_todo);

                /*
                 * nfs_token not held here.  slp token is held.
                 */
                if (nfsrv_dorec(slp, nfsd, &nd)) {
                        nfsd->nfsd_flag &= ~NFSD_REQINPROG;
                        if (slp->ns_flag & SLP_ACTION_MASK) {
                                lwkt_reltoken(&slp->ns_token);
                                lwkt_gettoken(&nfs_token);
                        } else {
                                nfsd->nfsd_slp = NULL;
                                lwkt_reltoken(&slp->ns_token);
                                lwkt_gettoken(&nfs_token);
                                nfsrv_slpderef(slp);
                        }
                } else {
                        lwkt_reltoken(&slp->ns_token);
                        lwkt_gettoken(&nfs_token);
                }
        }
done:
        TAILQ_REMOVE(&nfsd_head, nfsd, nfsd_chain);
        kfree((caddr_t)nfsd, M_NFSD);
        nsd->nsd_nfsd = NULL;
        if (--nfs_numnfsd == 0)
                nfsrv_init(TRUE);       /* Reinitialize everything */

        lwkt_reltoken(&nfs_token);
        return (error);
}

/*
 * Shut down a socket associated with an nfssvc_sock structure.
 * Should be called with the send lock set, if required.
 *
 * The trick here is to increment the sref at the start, so that the nfsds
 * will stop using it and clear ns_flag at the end so that it will not be
 * reassigned during cleanup.
 *
 * That said, while we shutdown() the socket here, we don't actually destroy
 * it until the final deref as there might be other code in the middle of
 * using it.
 */
static void
nfsrv_zapsock(struct nfssvc_sock *slp)
{
        struct nfsuid *nuidp, *nnuidp;
        struct nfsrv_descript *nwp, *nnwp;
        struct socket *so;
        struct nfsrv_rec *rec;
        int wasvalid;

        wasvalid = slp->ns_flag & SLP_VALID;
        slp->ns_flag &= ~SLP_ALLFLAGS;
        if (wasvalid && slp->ns_fp) {
                so = slp->ns_so;
                atomic_clear_int(&so->so_rcv.ssb_flags, SSB_UPCALL);
                so->so_upcall = NULL;
                so->so_upcallarg = NULL;
                soshutdown(so, SHUT_RDWR);
                if (slp->ns_nam) {
                        kfree(slp->ns_nam, M_SONAME);
                        slp->ns_nam = NULL;
                }

                m_freem(slp->ns_raw);
                slp->ns_raw = NULL;

                while ((rec = STAILQ_FIRST(&slp->ns_rec)) != NULL) {
                        --slp->ns_numrec;
                        STAILQ_REMOVE_HEAD(&slp->ns_rec, nr_link);
                        if (rec->nr_address)
                                kfree(rec->nr_address, M_SONAME);
                        m_freem(rec->nr_packet);
                        kfree(rec, M_NFSRVDESC);
                }
                KKASSERT(slp->ns_numrec == 0);

                TAILQ_FOREACH_MUTABLE(nuidp, &slp->ns_uidlruhead, nu_lru,
                                      nnuidp) {
                        LIST_REMOVE(nuidp, nu_hash);
                        TAILQ_REMOVE(&slp->ns_uidlruhead, nuidp, nu_lru);
                        if (nuidp->nu_flag & NU_NAM)
                                kfree(nuidp->nu_nam, M_SONAME);
                        kfree((caddr_t)nuidp, M_NFSUID);
                }
                crit_enter();   /* XXX doesn't do anything any more */
                for (nwp = slp->ns_tq.lh_first; nwp; nwp = nnwp) {
                        nnwp = nwp->nd_tq.le_next;
                        LIST_REMOVE(nwp, nd_tq);
                        kfree((caddr_t)nwp, M_NFSRVDESC);
                }
                LIST_INIT(&slp->ns_tq);
                crit_exit();

                nfsrv_slpderef(slp);
        }
}

/*
 * Derefence a server socket structure. If it has no more references and
 * is no longer valid, you can throw it away.
 *
 * Must be holding nfs_token!
 */
void
nfsrv_slpderef(struct nfssvc_sock *slp)
{
        struct file *fp;

        ASSERT_LWKT_TOKEN_HELD(&nfs_token);
        if (slp->ns_sref == 1) {
                KKASSERT((slp->ns_flag & SLP_VALID) == 0);
                TAILQ_REMOVE(&nfssvc_sockhead, slp, ns_chain);
                slp->ns_sref = 0;
                fp = slp->ns_fp;
                slp->ns_fp = NULL;
                slp->ns_so = NULL;
                if (fp)
                        closef(fp, NULL);
                kfree((caddr_t)slp, M_NFSSVC);
        } else {
                --slp->ns_sref;
        }
}

void
nfsrv_slpref(struct nfssvc_sock *slp)
{
        ASSERT_LWKT_TOKEN_HELD(&nfs_token);
        ++slp->ns_sref;
}

/*
 * Lock a socket against others.
 *
 * Returns 0 on failure, 1 on success.
 */
int
nfs_slplock(struct nfssvc_sock *slp, int wait)
{
        mtx_t *mtx = &slp->ns_solock;

        if (wait) {
                mtx_lock_ex(mtx, 0, 0);
                return(1);
        } else if (mtx_lock_ex_try(mtx) == 0) {
                return(1);
        } else {
                return(0);
        }
}

/*
 * Unlock the stream socket for others.
 */
void
nfs_slpunlock(struct nfssvc_sock *slp)
{
        mtx_t *mtx = &slp->ns_solock;

        mtx_unlock(mtx);
}

/*
 * Initialize the data structures for the server.
 * Handshake with any new nfsds starting up to avoid any chance of
 * corruption.
 */
void
nfsrv_init(int terminating)
{
        struct nfssvc_sock *slp, *nslp;

        lwkt_gettoken(&nfs_token);
        if (nfssvc_sockhead_flag & SLP_INIT)
                panic("nfsd init");
        nfssvc_sockhead_flag |= SLP_INIT;

        if (terminating) {
                TAILQ_FOREACH_MUTABLE(slp, &nfssvc_sockhead, ns_chain, nslp) {
                        nfsrv_slpref(slp);
                        lwkt_gettoken(&slp->ns_token);
                        if (slp->ns_flag & SLP_VALID)
                                nfsrv_zapsock(slp);
                        lwkt_reltoken(&slp->ns_token);
                        nfsrv_slpderef(slp);
                }
                nfsrv_cleancache();     /* And clear out server cache */
        } else {
                nfs_pub.np_valid = 0;
        }

        TAILQ_INIT(&nfssvc_sockhead);
        nfssvc_sockhead_flag &= ~SLP_INIT;
        if (nfssvc_sockhead_flag & SLP_WANTINIT) {
                nfssvc_sockhead_flag &= ~SLP_WANTINIT;
                wakeup((caddr_t)&nfssvc_sockhead);
        }

        TAILQ_INIT(&nfsd_head);
        nfsd_head_flag &= ~NFSD_CHECKSLP;

        lwkt_reltoken(&nfs_token);

#if 0
        nfs_udpsock = (struct nfssvc_sock *)
            kmalloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK | M_ZERO);
        mtx_init(&nfs_udpsock->ns_solock);
        STAILQ_INIT(&nfs_udpsock->ns_rec);
        TAILQ_INIT(&nfs_udpsock->ns_uidlruhead);
        TAILQ_INSERT_HEAD(&nfssvc_sockhead, nfs_udpsock, ns_chain);

        nfs_cltpsock = (struct nfssvc_sock *)
            kmalloc(sizeof (struct nfssvc_sock), M_NFSSVC, M_WAITOK | M_ZERO);
        mtx_init(&nfs_cltpsock->ns_solock);
        STAILQ_INIT(&nfs_cltpsock->ns_rec);
        TAILQ_INIT(&nfs_cltpsock->ns_uidlruhead);
        TAILQ_INSERT_TAIL(&nfssvc_sockhead, nfs_cltpsock, ns_chain);
#endif
}

/*
 * Add entries to the server monitor log.
 */
static void
nfsd_rt(int sotype, struct nfsrv_descript *nd, int cacherep)
{
        struct drt *rt;

        rt = &nfsdrt.drt[nfsdrt.pos];
        if (cacherep == RC_DOIT)
                rt->flag = 0;
        else if (cacherep == RC_REPLY)
                rt->flag = DRT_CACHEREPLY;
        else
                rt->flag = DRT_CACHEDROP;
        if (sotype == SOCK_STREAM)
                rt->flag |= DRT_TCP;
        if (nd->nd_flag & ND_NFSV3)
                rt->flag |= DRT_NFSV3;
        rt->proc = nd->nd_procnum;
        if (nd->nd_nam->sa_family == AF_INET)
            rt->ipadr = ((struct sockaddr_in *)nd->nd_nam)->sin_addr.s_addr;
        else
            rt->ipadr = INADDR_ANY;
        rt->resptime = nfs_curusec() - (nd->nd_starttime.tv_sec * 1000000 + nd->nd_starttime.tv_usec);
        getmicrotime(&rt->tstamp);
        nfsdrt.pos = (nfsdrt.pos + 1) % NFSRTTLOGSIZ;
}
#endif /* NFS_NOSERVER */

/*
 * Get an authorization string for the uid by having the mount_nfs sitting
 * on this mount point porpous out of the kernel and do it.
 */
int
nfs_getauth(struct nfsmount *nmp, struct nfsreq *rep,
            struct ucred *cred, char **auth_str, int *auth_len, char *verf_str,
            int *verf_len, NFSKERBKEY_T key /* return session key */)
{
        int error = 0;

        while ((nmp->nm_state & NFSSTA_WAITAUTH) == 0) {
                nmp->nm_state |= NFSSTA_WANTAUTH;
                (void) tsleep((caddr_t)&nmp->nm_authtype, 0,
                        "nfsauth1", 2 * hz);
                error = nfs_sigintr(nmp, rep, rep->r_td);
                if (error) {
                        nmp->nm_state &= ~NFSSTA_WANTAUTH;
                        return (error);
                }
        }
        nmp->nm_state &= ~(NFSSTA_WAITAUTH | NFSSTA_WANTAUTH);
        nmp->nm_authstr = *auth_str = (char *)kmalloc(RPCAUTH_MAXSIZ, M_TEMP, M_WAITOK);
        nmp->nm_authlen = RPCAUTH_MAXSIZ;
        nmp->nm_verfstr = verf_str;
        nmp->nm_verflen = *verf_len;
        nmp->nm_authuid = cred->cr_uid;
        wakeup((caddr_t)&nmp->nm_authstr);

        /*
         * And wait for mount_nfs to do its stuff.
         */
        while ((nmp->nm_state & NFSSTA_HASAUTH) == 0 && error == 0) {
                (void) tsleep((caddr_t)&nmp->nm_authlen, 0,
                        "nfsauth2", 2 * hz);
                error = nfs_sigintr(nmp, rep, rep->r_td);
        }
        if (nmp->nm_state & NFSSTA_AUTHERR) {
                nmp->nm_state &= ~NFSSTA_AUTHERR;
                error = EAUTH;
        }
        if (error)
                kfree((caddr_t)*auth_str, M_TEMP);
        else {
                *auth_len = nmp->nm_authlen;
                *verf_len = nmp->nm_verflen;
                bcopy((caddr_t)nmp->nm_key, (caddr_t)key, sizeof (NFSKERBKEY_T));
        }
        nmp->nm_state &= ~NFSSTA_HASAUTH;
        nmp->nm_state |= NFSSTA_WAITAUTH;
        if (nmp->nm_state & NFSSTA_WANTAUTH) {
                nmp->nm_state &= ~NFSSTA_WANTAUTH;
                wakeup((caddr_t)&nmp->nm_authtype);
        }
        return (error);
}

/*
 * Get a nickname authenticator and verifier.
 */
int
nfs_getnickauth(struct nfsmount *nmp, struct ucred *cred, char **auth_str,
                int *auth_len, char *verf_str, int verf_len)
{
        struct nfsuid *nuidp;
        u_int32_t *nickp, *verfp;
        struct timeval ktvout;

#ifdef DIAGNOSTIC
        if (verf_len < (4 * NFSX_UNSIGNED))
                panic("nfs_getnickauth verf too small");
#endif
        for (nuidp = NMUIDHASH(nmp, cred->cr_uid)->lh_first;
            nuidp != NULL; nuidp = nuidp->nu_hash.le_next) {
                if (nuidp->nu_cr.cr_uid == cred->cr_uid)
                        break;
        }
        if (!nuidp || nuidp->nu_expire < time_uptime)
                return (EACCES);

        /*
         * Move to the end of the lru list (end of lru == most recently used).
         */
        TAILQ_REMOVE(&nmp->nm_uidlruhead, nuidp, nu_lru);
        TAILQ_INSERT_TAIL(&nmp->nm_uidlruhead, nuidp, nu_lru);

        nickp = (u_int32_t *)kmalloc(2 * NFSX_UNSIGNED, M_TEMP, M_WAITOK);
        *nickp++ = txdr_unsigned(RPCAKN_NICKNAME);
        *nickp = txdr_unsigned(nuidp->nu_nickname);
        *auth_str = (char *)nickp;
        *auth_len = 2 * NFSX_UNSIGNED;

        /*
         * Now we must encrypt the verifier and package it up.
         */
        verfp = (u_int32_t *)verf_str;
        *verfp++ = txdr_unsigned(RPCAKN_NICKNAME);
        if (time_second != nuidp->nu_timestamp.tv_sec ||
            time_second > nuidp->nu_timestamp.tv_usec)          /* XXX */
                getmicrotime(&nuidp->nu_timestamp);
        else
                nuidp->nu_timestamp.tv_usec++;

        /*
         * Now encrypt the timestamp verifier in ecb mode using the session
         * key.
         */
#ifdef NFSKERB
        XXX
#else
        ktvout.tv_sec = 0;
        ktvout.tv_usec = 0;
#endif

        *verfp++ = ktvout.tv_sec;
        *verfp++ = ktvout.tv_usec;
        *verfp = 0;
        return (0);
}

/*
 * Save the current nickname in a hash list entry on the mount point.
 */
int
nfs_savenickauth(struct nfsmount *nmp, struct ucred *cred, int len,
                 NFSKERBKEY_T key, struct mbuf **mdp, char **dposp,
                 struct mbuf *mrep)
{
        struct nfsuid *nuidp;
        u_int32_t *tl;
        struct timeval ktvin, ktvout;
        u_int32_t nick;
        int deltasec, error = 0;
        struct nfsm_info info;

        info.md = *mdp;
        info.dpos = *dposp;
        info.mrep = mrep;

        if (len == (3 * NFSX_UNSIGNED)) {
                NULLOUT(tl = nfsm_dissect(&info, 3 * NFSX_UNSIGNED));
                ktvin.tv_sec = *tl++;
                ktvin.tv_usec = *tl++;
                nick = fxdr_unsigned(u_int32_t, *tl);

                /*
                 * Decrypt the timestamp in ecb mode.
                 */
#ifdef NFSKERB
                XXX
#else
                ktvout.tv_sec = 0;
                ktvout.tv_usec = 0;
#endif
                ktvout.tv_sec = fxdr_unsigned(long, ktvout.tv_sec);
                ktvout.tv_usec = fxdr_unsigned(long, ktvout.tv_usec);
                deltasec = time_second - ktvout.tv_sec;
                if (deltasec < 0)
                        deltasec = -deltasec;
                /*
                 * If ok, add it to the hash list for the mount point.
                 */
                if (deltasec <= NFS_KERBCLOCKSKEW) {
                        if (nmp->nm_numuids < nuidhash_max) {
                                nmp->nm_numuids++;
                                nuidp = (struct nfsuid *)
                                   kmalloc(sizeof (struct nfsuid), M_NFSUID,
                                        M_WAITOK);
                        } else {
                                nuidp = TAILQ_FIRST(&nmp->nm_uidlruhead);
                                LIST_REMOVE(nuidp, nu_hash);
                                TAILQ_REMOVE(&nmp->nm_uidlruhead, nuidp,
                                        nu_lru);
                        }
                        nuidp->nu_flag = 0;
                        nuidp->nu_cr.cr_uid = cred->cr_uid;
                        nuidp->nu_expire = time_uptime + NFS_KERBTTL;
                        nuidp->nu_timestamp = ktvout;
                        nuidp->nu_nickname = nick;
                        bcopy(key, nuidp->nu_key, sizeof (NFSKERBKEY_T));
                        TAILQ_INSERT_TAIL(&nmp->nm_uidlruhead, nuidp,
                                nu_lru);
                        LIST_INSERT_HEAD(NMUIDHASH(nmp, cred->cr_uid),
                                nuidp, nu_hash);
                }
        } else {
                ERROROUT(nfsm_adv(&info, nfsm_rndup(len)));
        }
nfsmout:
        *mdp = info.md;
        *dposp = info.dpos;
        return (error);
}