xnu-3248.20.55.tar.gz

[apple/xnu.git] / bsd / nfs / nfs_subs.c

/*
 * Copyright (c) 2000-2014 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)nfs_subs.c  8.8 (Berkeley) 5/22/95
 * FreeBSD-Id: nfs_subs.c,v 1.47 1997/11/07 08:53:24 phk Exp $
 */

/*
 * These functions support the macros and help fiddle mbuf chains for
 * the nfs op functions. They do things like create the rpc header and
 * copy data between mbuf chains and uio lists.
 */
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/kauth.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mount_internal.h>
#include <sys/vnode_internal.h>
#include <sys/kpi_mbuf.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/malloc.h>
#include <sys/syscall.h>
#include <sys/ubc_internal.h>
#include <sys/fcntl.h>
#include <sys/uio.h>
#include <sys/domain.h>
#include <libkern/OSAtomic.h>
#include <kern/thread_call.h>

#include <sys/vm.h>
#include <sys/vmparam.h>

#include <sys/time.h>
#include <kern/clock.h>

#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <nfs/nfsnode.h>
#if NFSCLIENT
#define _NFS_XDR_SUBS_FUNCS_ /* define this to get xdrbuf function definitions */
#endif
#include <nfs/xdr_subs.h>
#include <nfs/nfsm_subs.h>
#include <nfs/nfs_gss.h>
#include <nfs/nfsmount.h>
#include <nfs/nfs_lock.h>

#include <miscfs/specfs/specdev.h>

#include <netinet/in.h>
#include <net/kpi_interface.h>

#include <sys/utfconv.h>

/*
 * NFS globals
 */
struct nfsstats __attribute__((aligned(8))) nfsstats;
size_t nfs_mbuf_mhlen = 0, nfs_mbuf_minclsize = 0;

/*
 * functions to convert between NFS and VFS types
 */
nfstype
vtonfs_type(enum vtype vtype, int nfsvers)
{
        switch (vtype) {
        case VNON:
                return NFNON;
        case VREG:
                return NFREG;
        case VDIR:
                return NFDIR;
        case VBLK:
                return NFBLK;
        case VCHR:
                return NFCHR;
        case VLNK:
                return NFLNK;
        case VSOCK:
                if (nfsvers > NFS_VER2)
                        return NFSOCK;
        case VFIFO:
                if (nfsvers > NFS_VER2)
                        return NFFIFO;
        case VBAD:
        case VSTR:
        case VCPLX:
        default:
                return NFNON;
        }
}

enum vtype
nfstov_type(nfstype nvtype, int nfsvers)
{
        switch (nvtype) {
        case NFNON:
                return VNON;
        case NFREG:
                return VREG;
        case NFDIR:
                return VDIR;
        case NFBLK:
                return VBLK;
        case NFCHR:
                return VCHR;
        case NFLNK:
                return VLNK;
        case NFSOCK:
                if (nfsvers > NFS_VER2)
                        return VSOCK;
        case NFFIFO:
                if (nfsvers > NFS_VER2)
                        return VFIFO;
        case NFATTRDIR:
                if (nfsvers > NFS_VER3)
                        return VDIR;
        case NFNAMEDATTR:
                if (nfsvers > NFS_VER3)
                        return VREG;
        default:
                return VNON;
        }
}

int
vtonfsv2_mode(enum vtype vtype, mode_t m)
{
        switch (vtype) {
        case VNON:
        case VREG:
        case VDIR:
        case VBLK:
        case VCHR:
        case VLNK:
        case VSOCK:
                return vnode_makeimode(vtype, m);
        case VFIFO:
                return vnode_makeimode(VCHR, m);
        case VBAD:
        case VSTR:
        case VCPLX:
        default:
                return vnode_makeimode(VNON, m);
        }
}

#if NFSSERVER

/*
 * Mapping of old NFS Version 2 RPC numbers to generic numbers.
 */
int nfsv3_procid[NFS_NPROCS] = {
        NFSPROC_NULL,
        NFSPROC_GETATTR,
        NFSPROC_SETATTR,
        NFSPROC_NOOP,
        NFSPROC_LOOKUP,
        NFSPROC_READLINK,
        NFSPROC_READ,
        NFSPROC_NOOP,
        NFSPROC_WRITE,
        NFSPROC_CREATE,
        NFSPROC_REMOVE,
        NFSPROC_RENAME,
        NFSPROC_LINK,
        NFSPROC_SYMLINK,
        NFSPROC_MKDIR,
        NFSPROC_RMDIR,
        NFSPROC_READDIR,
        NFSPROC_FSSTAT,
        NFSPROC_NOOP,
        NFSPROC_NOOP,
        NFSPROC_NOOP,
        NFSPROC_NOOP,
        NFSPROC_NOOP
};

#endif /* NFSSERVER */

/*
 * and the reverse mapping from generic to Version 2 procedure numbers
 */
int nfsv2_procid[NFS_NPROCS] = {
        NFSV2PROC_NULL,
        NFSV2PROC_GETATTR,
        NFSV2PROC_SETATTR,
        NFSV2PROC_LOOKUP,
        NFSV2PROC_NOOP,
        NFSV2PROC_READLINK,
        NFSV2PROC_READ,
        NFSV2PROC_WRITE,
        NFSV2PROC_CREATE,
        NFSV2PROC_MKDIR,
        NFSV2PROC_SYMLINK,
        NFSV2PROC_CREATE,
        NFSV2PROC_REMOVE,
        NFSV2PROC_RMDIR,
        NFSV2PROC_RENAME,
        NFSV2PROC_LINK,
        NFSV2PROC_READDIR,
        NFSV2PROC_NOOP,
        NFSV2PROC_STATFS,
        NFSV2PROC_NOOP,
        NFSV2PROC_NOOP,
        NFSV2PROC_NOOP,
        NFSV2PROC_NOOP
};


/*
 * initialize NFS's cache of mbuf constants
 */
void
nfs_mbuf_init(void)
{
        struct mbuf_stat ms;

        mbuf_stats(&ms);
        nfs_mbuf_mhlen = ms.mhlen;
        nfs_mbuf_minclsize = ms.minclsize;
}

#if NFSSERVER

/*
 * allocate a list of mbufs to hold the given amount of data
 */
int
nfsm_mbuf_get_list(size_t size, mbuf_t *mp, int *mbcnt)
{
        int error, cnt;
        mbuf_t mhead, mlast, m;
        size_t len, mlen;

        error = cnt = 0;
        mhead = mlast = NULL;
        len = 0;

        while (len < size) {
                nfsm_mbuf_get(error, &m, (size - len));
                if (error)
                        break;
                if (!mhead)
                        mhead = m;
                if (mlast && ((error = mbuf_setnext(mlast, m)))) {
                        mbuf_free(m);
                        break;
                }
                mlen = mbuf_maxlen(m);
                if ((len + mlen) > size)
                        mlen = size - len;
                mbuf_setlen(m, mlen);
                len += mlen;
                cnt++;
                mlast = m;
        }

        if (!error) {
                *mp = mhead;
                *mbcnt = cnt;
        }
        return (error);
}

#endif /* NFSSERVER */

/*
 * nfsm_chain_new_mbuf()
 *
 * Add a new mbuf to the given chain.
 */
int
nfsm_chain_new_mbuf(struct nfsm_chain *nmc, size_t sizehint)
{
        mbuf_t mb;
        int error = 0;

        if (nmc->nmc_flags & NFSM_CHAIN_FLAG_ADD_CLUSTERS)
                sizehint = nfs_mbuf_minclsize;

        /* allocate a new mbuf */
        nfsm_mbuf_get(error, &mb, sizehint);
        if (error)
                return (error);
        if (mb == NULL)
                panic("got NULL mbuf?");

        /* do we have a current mbuf? */
        if (nmc->nmc_mcur) {
                /* first cap off current mbuf */
                mbuf_setlen(nmc->nmc_mcur, nmc->nmc_ptr - (caddr_t)mbuf_data(nmc->nmc_mcur));
                /* then append the new mbuf */
                error = mbuf_setnext(nmc->nmc_mcur, mb);
                if (error) {
                        mbuf_free(mb);
                        return (error);
                }
        }

        /* set up for using the new mbuf */
        nmc->nmc_mcur = mb;
        nmc->nmc_ptr = mbuf_data(mb);
        nmc->nmc_left = mbuf_trailingspace(mb);

        return (0);
}

/*
 * nfsm_chain_add_opaque_f()
 *
 * Add "len" bytes of opaque data pointed to by "buf" to the given chain.
 */
int
nfsm_chain_add_opaque_f(struct nfsm_chain *nmc, const u_char *buf, uint32_t len)
{
        uint32_t paddedlen, tlen;
        int error;

        paddedlen = nfsm_rndup(len);

        while (paddedlen) {
                if (!nmc->nmc_left) {
                        error = nfsm_chain_new_mbuf(nmc, paddedlen);
                        if (error)
                                return (error);
                }
                tlen = MIN(nmc->nmc_left, paddedlen);
                if (tlen) {
                        if (len) {
                                if (tlen > len)
                                        tlen = len;
                                bcopy(buf, nmc->nmc_ptr, tlen);
                        } else {
                                bzero(nmc->nmc_ptr, tlen);
                        }
                        nmc->nmc_ptr += tlen;
                        nmc->nmc_left -= tlen;
                        paddedlen -= tlen;
                        if (len) {
                                buf += tlen;
                                len -= tlen;
                        }
                }
        }
        return (0);
}

/*
 * nfsm_chain_add_opaque_nopad_f()
 *
 * Add "len" bytes of opaque data pointed to by "buf" to the given chain.
 * Do not XDR pad.
 */
int
nfsm_chain_add_opaque_nopad_f(struct nfsm_chain *nmc, const u_char *buf, uint32_t len)
{
        uint32_t tlen;
        int error;

        while (len > 0) {
                if (nmc->nmc_left <= 0) {
                        error = nfsm_chain_new_mbuf(nmc, len);
                        if (error)
                                return (error);
                }
                tlen = MIN(nmc->nmc_left, len);
                bcopy(buf, nmc->nmc_ptr, tlen);
                nmc->nmc_ptr += tlen;
                nmc->nmc_left -= tlen;
                len -= tlen;
                buf += tlen;
        }
        return (0);
}

/*
 * nfsm_chain_add_uio()
 *
 * Add "len" bytes of data from "uio" to the given chain.
 */
int
nfsm_chain_add_uio(struct nfsm_chain *nmc, uio_t uio, uint32_t len)
{
        uint32_t paddedlen, tlen;
        int error;

        paddedlen = nfsm_rndup(len);

        while (paddedlen) {
                if (!nmc->nmc_left) {
                        error = nfsm_chain_new_mbuf(nmc, paddedlen);
                        if (error)
                                return (error);
                }
                tlen = MIN(nmc->nmc_left, paddedlen);
                if (tlen) {
                        if (len) {
                                if (tlen > len)
                                        tlen = len;
                                uiomove(nmc->nmc_ptr, tlen, uio);
                        } else {
                                bzero(nmc->nmc_ptr, tlen);
                        }
                        nmc->nmc_ptr += tlen;
                        nmc->nmc_left -= tlen;
                        paddedlen -= tlen;
                        if (len)
                                len -= tlen;
                }
        }
        return (0);
}

/*
 * Find the length of the NFS mbuf chain
 * up to the current encoding/decoding offset.
 */
int
nfsm_chain_offset(struct nfsm_chain *nmc)
{
        mbuf_t mb;
        int len = 0;

        for (mb = nmc->nmc_mhead; mb; mb = mbuf_next(mb)) {
                if (mb == nmc->nmc_mcur)
                        return (len + (nmc->nmc_ptr - (caddr_t) mbuf_data(mb)));
                len += mbuf_len(mb);
        }

        return (len);
}

/*
 * nfsm_chain_advance()
 *
 * Advance an nfsm_chain by "len" bytes.
 */
int
nfsm_chain_advance(struct nfsm_chain *nmc, uint32_t len)
{
        mbuf_t mb;

        while (len) {
                if (nmc->nmc_left >= len) {
                        nmc->nmc_left -= len;
                        nmc->nmc_ptr += len;
                        return (0);
                }
                len -= nmc->nmc_left;
                nmc->nmc_mcur = mb = mbuf_next(nmc->nmc_mcur);
                if (!mb)
                        return (EBADRPC);
                nmc->nmc_ptr = mbuf_data(mb);
                nmc->nmc_left = mbuf_len(mb);
        }

        return (0);
}

/*
 * nfsm_chain_reverse()
 *
 * Reverse decode offset in an nfsm_chain by "len" bytes.
 */
int
nfsm_chain_reverse(struct nfsm_chain *nmc, uint32_t len)
{
        uint32_t mlen, new_offset;
        int error = 0;

        mlen = nmc->nmc_ptr - (caddr_t) mbuf_data(nmc->nmc_mcur);
        if (len <= mlen) {
                nmc->nmc_ptr -= len;
                nmc->nmc_left += len;
                return (0);
        }

        new_offset = nfsm_chain_offset(nmc) - len;
        nfsm_chain_dissect_init(error, nmc, nmc->nmc_mhead);
        if (error)
                return (error);

        return (nfsm_chain_advance(nmc, new_offset));
}

/*
 * nfsm_chain_get_opaque_pointer_f()
 *
 * Return a pointer to the next "len" bytes of contiguous data in
 * the mbuf chain.  If the next "len" bytes are not contiguous, we
 * try to manipulate the mbuf chain so that it is.
 *
 * The nfsm_chain is advanced by nfsm_rndup("len") bytes.
 */
int
nfsm_chain_get_opaque_pointer_f(struct nfsm_chain *nmc, uint32_t len, u_char **pptr)
{
        mbuf_t mbcur, mb;
        uint32_t left, need, mblen, cplen, padlen;
        u_char *ptr;
        int error = 0;

        /* move to next mbuf with data */
        while (nmc->nmc_mcur && (nmc->nmc_left == 0)) {
                mb = mbuf_next(nmc->nmc_mcur);
                nmc->nmc_mcur = mb;
                if (!mb)
                        break;
                nmc->nmc_ptr = mbuf_data(mb);
                nmc->nmc_left = mbuf_len(mb);
        }
        /* check if we've run out of data */
        if (!nmc->nmc_mcur)
                return (EBADRPC);

        /* do we already have a contiguous buffer? */
        if (nmc->nmc_left >= len) {
                /* the returned pointer will be the current pointer */
                *pptr = (u_char*)nmc->nmc_ptr;
                error = nfsm_chain_advance(nmc, nfsm_rndup(len));
                return (error);
        }

        padlen = nfsm_rndup(len) - len;

        /* we need (len - left) more bytes */
        mbcur = nmc->nmc_mcur;
        left = nmc->nmc_left;
        need = len - left;

        if (need > mbuf_trailingspace(mbcur)) {
                /*
                 * The needed bytes won't fit in the current mbuf so we'll
                 * allocate a new mbuf to hold the contiguous range of data.
                 */
                nfsm_mbuf_get(error, &mb, len);
                if (error)
                        return (error);
                /* double check that this mbuf can hold all the data */
                if (mbuf_maxlen(mb) < len) {
                        mbuf_free(mb);
                        return (EOVERFLOW);
                }

                /* the returned pointer will be the new mbuf's data pointer */
                *pptr = ptr = mbuf_data(mb);

                /* copy "left" bytes to the new mbuf */
                bcopy(nmc->nmc_ptr, ptr, left);
                ptr += left;
                mbuf_setlen(mb, left);

                /* insert the new mbuf between the current and next mbufs */
                error = mbuf_setnext(mb, mbuf_next(mbcur));
                if (!error)
                        error = mbuf_setnext(mbcur, mb);
                if (error) {
                        mbuf_free(mb);
                        return (error);
                }

                /* reduce current mbuf's length by "left" */
                mbuf_setlen(mbcur, mbuf_len(mbcur) - left);

                /*
                 * update nmc's state to point at the end of the mbuf
                 * where the needed data will be copied to.
                 */
                nmc->nmc_mcur = mbcur = mb;
                nmc->nmc_left = 0;
                nmc->nmc_ptr = (caddr_t)ptr;
        } else {
                /* The rest of the data will fit in this mbuf. */

                /* the returned pointer will be the current pointer */
                *pptr = (u_char*)nmc->nmc_ptr;

                /*
                 * update nmc's state to point at the end of the mbuf
                 * where the needed data will be copied to.
                 */
                nmc->nmc_ptr += left;
                nmc->nmc_left = 0;
        }

        /*
         * move the next "need" bytes into the current
         * mbuf from the mbufs that follow
         */

        /* extend current mbuf length */
        mbuf_setlen(mbcur, mbuf_len(mbcur) + need);

        /* mb follows mbufs we're copying/compacting data from */
        mb = mbuf_next(mbcur);

        while (need && mb) {
                /* copy as much as we need/can */
                ptr = mbuf_data(mb);
                mblen = mbuf_len(mb);
                cplen = MIN(mblen, need);
                if (cplen) {
                        bcopy(ptr, nmc->nmc_ptr, cplen);
                        /*
                         * update the mbuf's pointer and length to reflect that
                         * the data was shifted to an earlier mbuf in the chain
                         */
                        error = mbuf_setdata(mb, ptr + cplen, mblen - cplen);
                        if (error) {
                                mbuf_setlen(mbcur, mbuf_len(mbcur) - need);
                                return (error);
                        }
                        /* update pointer/need */
                        nmc->nmc_ptr += cplen;
                        need -= cplen;
                }
                /* if more needed, go to next mbuf */
                if (need)
                        mb = mbuf_next(mb);
        }

        /* did we run out of data in the mbuf chain? */
        if (need) {
                mbuf_setlen(mbcur, mbuf_len(mbcur) - need);
                return (EBADRPC);
        }

        /*
         * update nmc's state to point after this contiguous data
         *
         * "mb" points to the last mbuf we copied data from so we
         * just set nmc to point at whatever remains in that mbuf.
         */
        nmc->nmc_mcur = mb;
        nmc->nmc_ptr = mbuf_data(mb);
        nmc->nmc_left = mbuf_len(mb);

        /* move past any padding */
        if (padlen)
                error = nfsm_chain_advance(nmc, padlen);

        return (error);
}

/*
 * nfsm_chain_get_opaque_f()
 *
 * Read the next "len" bytes in the chain into "buf".
 * The nfsm_chain is advanced by nfsm_rndup("len") bytes.
 */
int
nfsm_chain_get_opaque_f(struct nfsm_chain *nmc, uint32_t len, u_char *buf)
{
        uint32_t cplen, padlen;
        int error = 0;

        padlen = nfsm_rndup(len) - len;

        /* loop through mbufs copying all the data we need */
        while (len && nmc->nmc_mcur) {
                /* copy as much as we need/can */
                cplen = MIN(nmc->nmc_left, len);
                if (cplen) {
                        bcopy(nmc->nmc_ptr, buf, cplen);
                        nmc->nmc_ptr += cplen;
                        nmc->nmc_left -= cplen;
                        buf += cplen;
                        len -= cplen;
                }
                /* if more needed, go to next mbuf */
                if (len) {
                        mbuf_t mb = mbuf_next(nmc->nmc_mcur);
                        nmc->nmc_mcur = mb;
                        nmc->nmc_ptr = mb ? mbuf_data(mb) : NULL;
                        nmc->nmc_left = mb ? mbuf_len(mb) : 0;
                }
        }

        /* did we run out of data in the mbuf chain? */
        if (len)
                return (EBADRPC);

        if (padlen)
                nfsm_chain_adv(error, nmc, padlen);

        return (error);
}

/*
 * nfsm_chain_get_uio()
 *
 * Read the next "len" bytes in the chain into the given uio.
 * The nfsm_chain is advanced by nfsm_rndup("len") bytes.
 */
int
nfsm_chain_get_uio(struct nfsm_chain *nmc, uint32_t len, uio_t uio)
{
        uint32_t cplen, padlen;
        int error = 0;

        padlen = nfsm_rndup(len) - len;

        /* loop through mbufs copying all the data we need */
        while (len && nmc->nmc_mcur) {
                /* copy as much as we need/can */
                cplen = MIN(nmc->nmc_left, len);
                if (cplen) {
                        error = uiomove(nmc->nmc_ptr, cplen, uio);
                        if (error)
                                return (error);
                        nmc->nmc_ptr += cplen;
                        nmc->nmc_left -= cplen;
                        len -= cplen;
                }
                /* if more needed, go to next mbuf */
                if (len) {
                        mbuf_t mb = mbuf_next(nmc->nmc_mcur);
                        nmc->nmc_mcur = mb;
                        nmc->nmc_ptr = mb ? mbuf_data(mb) : NULL;
                        nmc->nmc_left = mb ? mbuf_len(mb) : 0;
                }
        }

        /* did we run out of data in the mbuf chain? */
        if (len)
                return (EBADRPC);

        if (padlen)
                nfsm_chain_adv(error, nmc, padlen);

        return (error);
}

#if NFSCLIENT

int
nfsm_chain_add_string_nfc(struct nfsm_chain *nmc, const uint8_t *s, uint32_t slen)
{
        uint8_t smallbuf[64];
        uint8_t *nfcname = smallbuf;
        size_t buflen = sizeof(smallbuf), nfclen;
        int error;

        error = utf8_normalizestr(s, slen, nfcname, &nfclen, buflen, UTF_PRECOMPOSED|UTF_NO_NULL_TERM);
        if (error == ENAMETOOLONG) {
                buflen = MAXPATHLEN;
                MALLOC_ZONE(nfcname, uint8_t *, MAXPATHLEN, M_NAMEI, M_WAITOK);
                if (nfcname)
                        error = utf8_normalizestr(s, slen, nfcname, &nfclen, buflen, UTF_PRECOMPOSED|UTF_NO_NULL_TERM);
        }

        /* if we got an error, just use the original string */
        if (error)
                nfsm_chain_add_string(error, nmc, s, slen);
        else
                nfsm_chain_add_string(error, nmc, nfcname, nfclen);

        if (nfcname && (nfcname != smallbuf))
                FREE_ZONE(nfcname, MAXPATHLEN, M_NAMEI);
        return (error);
}

/*
 * Add an NFSv2 "sattr" structure to an mbuf chain
 */
int
nfsm_chain_add_v2sattr_f(struct nfsm_chain *nmc, struct vnode_attr *vap, uint32_t szrdev)
{
        int error = 0;

        nfsm_chain_add_32(error, nmc, vtonfsv2_mode(vap->va_type,
                (VATTR_IS_ACTIVE(vap, va_mode) ? vap->va_mode : 0600)));
        nfsm_chain_add_32(error, nmc,
                VATTR_IS_ACTIVE(vap, va_uid) ? vap->va_uid : (uint32_t)-1);
        nfsm_chain_add_32(error, nmc,
                VATTR_IS_ACTIVE(vap, va_gid) ? vap->va_gid : (uint32_t)-1);
        nfsm_chain_add_32(error, nmc, szrdev);
        nfsm_chain_add_v2time(error, nmc,
                VATTR_IS_ACTIVE(vap, va_access_time) ?
                &vap->va_access_time : NULL);
        nfsm_chain_add_v2time(error, nmc,
                VATTR_IS_ACTIVE(vap, va_modify_time) ?
                &vap->va_modify_time : NULL);

        return (error);
}

/*
 * Add an NFSv3 "sattr" structure to an mbuf chain
 */
int
nfsm_chain_add_v3sattr_f(struct nfsm_chain *nmc, struct vnode_attr *vap)
{
        int error = 0;

        if (VATTR_IS_ACTIVE(vap, va_mode)) {
                nfsm_chain_add_32(error, nmc, TRUE);
                nfsm_chain_add_32(error, nmc, vap->va_mode);
        } else {
                nfsm_chain_add_32(error, nmc, FALSE);
        }
        if (VATTR_IS_ACTIVE(vap, va_uid)) {
                nfsm_chain_add_32(error, nmc, TRUE);
                nfsm_chain_add_32(error, nmc, vap->va_uid);
        } else {
                nfsm_chain_add_32(error, nmc, FALSE);
        }
        if (VATTR_IS_ACTIVE(vap, va_gid)) {
                nfsm_chain_add_32(error, nmc, TRUE);
                nfsm_chain_add_32(error, nmc, vap->va_gid);
        } else {
                nfsm_chain_add_32(error, nmc, FALSE);
        }
        if (VATTR_IS_ACTIVE(vap, va_data_size)) {
                nfsm_chain_add_32(error, nmc, TRUE);
                nfsm_chain_add_64(error, nmc, vap->va_data_size);
        } else {
                nfsm_chain_add_32(error, nmc, FALSE);
        }
        if (vap->va_vaflags & VA_UTIMES_NULL) {
                nfsm_chain_add_32(error, nmc, NFS_TIME_SET_TO_SERVER);
                nfsm_chain_add_32(error, nmc, NFS_TIME_SET_TO_SERVER);
        } else {
                if (VATTR_IS_ACTIVE(vap, va_access_time)) {
                        nfsm_chain_add_32(error, nmc, NFS_TIME_SET_TO_CLIENT);
                        nfsm_chain_add_32(error, nmc, vap->va_access_time.tv_sec);
                        nfsm_chain_add_32(error, nmc, vap->va_access_time.tv_nsec);
                } else {
                        nfsm_chain_add_32(error, nmc, NFS_TIME_DONT_CHANGE);
                }
                if (VATTR_IS_ACTIVE(vap, va_modify_time)) {
                        nfsm_chain_add_32(error, nmc, NFS_TIME_SET_TO_CLIENT);
                        nfsm_chain_add_32(error, nmc, vap->va_modify_time.tv_sec);
                        nfsm_chain_add_32(error, nmc, vap->va_modify_time.tv_nsec);
                } else {
                        nfsm_chain_add_32(error, nmc, NFS_TIME_DONT_CHANGE);
                }
        }

        return (error);
}


/*
 * nfsm_chain_get_fh_attr()
 *
 * Get the file handle and attributes from an mbuf chain. (NFSv2/v3)
 */
int
nfsm_chain_get_fh_attr(
        struct nfsm_chain *nmc,
        nfsnode_t dnp,
        vfs_context_t ctx,
        int nfsvers,
        uint64_t *xidp,
        fhandle_t *fhp,
        struct nfs_vattr *nvap)
{
        int error = 0, gotfh, gotattr;

        gotfh = gotattr = 1;

        if (nfsvers == NFS_VER3) /* check for file handle */
                nfsm_chain_get_32(error, nmc, gotfh);
        if (!error && gotfh) /* get file handle */
                nfsm_chain_get_fh(error, nmc, nfsvers, fhp);
        else
                fhp->fh_len = 0;
        if (nfsvers == NFS_VER3) /* check for file attributes */
                nfsm_chain_get_32(error, nmc, gotattr);
        nfsmout_if(error);
        if (gotattr) {
                if (!gotfh) /* skip attributes */
                        nfsm_chain_adv(error, nmc, NFSX_V3FATTR);
                else /* get attributes */
                        error = nfs_parsefattr(nmc, nfsvers, nvap);
        } else if (gotfh) {
                /* we need valid attributes in order to call nfs_nget() */
                if (nfs3_getattr_rpc(NULL, NFSTOMP(dnp), fhp->fh_data, fhp->fh_len, 0, ctx, nvap, xidp)) {
                        gotattr = 0;
                        fhp->fh_len = 0;
                }
        }
nfsmout:
        return (error);
}

/*
 * Get and process NFSv3 WCC data from an mbuf chain
 */
int
nfsm_chain_get_wcc_data_f(
        struct nfsm_chain *nmc,
        nfsnode_t np,
        struct timespec *premtime,
        int *newpostattr,
        u_int64_t *xidp)
{
        int error = 0;
        uint32_t flag = 0;

        nfsm_chain_get_32(error, nmc, flag);
        if (!error && flag) {
                nfsm_chain_adv(error, nmc, 2 * NFSX_UNSIGNED);
                nfsm_chain_get_32(error, nmc, premtime->tv_sec);
                nfsm_chain_get_32(error, nmc, premtime->tv_nsec);
                nfsm_chain_adv(error, nmc, 2 * NFSX_UNSIGNED);
        } else {
                premtime->tv_sec = 0;
                premtime->tv_nsec = 0;
        }
        nfsm_chain_postop_attr_update_flag(error, nmc, np, *newpostattr, xidp);

        return (error);
}

/*
 * Get the next RPC transaction ID (XID)
 */
void
nfs_get_xid(uint64_t *xidp)
{
        struct timeval tv;

        lck_mtx_lock(nfs_request_mutex);
        if (!nfs_xid) {
                /*
                 * Derive initial xid from system time.
                 *
                 * Note: it's OK if this code inits nfs_xid to 0 (for example,
                 * due to a broken clock) because we immediately increment it
                 * and we guarantee to never use xid 0.  So, nfs_xid should only
                 * ever be 0 the first time this function is called.
                 */
                microtime(&tv);
                nfs_xid = tv.tv_sec << 12;
        }
        if (++nfs_xid == 0) {
                /* Skip zero xid if it should ever happen. */
                nfs_xidwrap++;
                nfs_xid++;
        }
        *xidp = nfs_xid + ((uint64_t)nfs_xidwrap << 32);
        lck_mtx_unlock(nfs_request_mutex);
}

/*
 * Build the RPC header and fill in the authorization info.
 * Returns the head of the mbuf list and the xid.
 */

int
nfsm_rpchead(
        struct nfsreq *req,
        mbuf_t mrest,
        u_int64_t *xidp,
        mbuf_t *mreqp)
{
        struct nfsmount *nmp = req->r_nmp;
        int nfsvers = nmp->nm_vers;
        int proc = ((nfsvers == NFS_VER2) ? nfsv2_procid[req->r_procnum] : (int)req->r_procnum);

        return nfsm_rpchead2(nmp, nmp->nm_sotype, NFS_PROG, nfsvers, proc,
                        req->r_auth, req->r_cred, req, mrest, xidp, mreqp);
}

/*
 * get_auiliary_groups: Gets the supplementary groups from a credential.
 *
 * IN:          cred:   credential to get the associated groups from.
 * OUT:         groups: An array of gids of NGROUPS size.
 * IN:          count:  The number of groups to get; i.e.; the number of groups the server supports
 *
 * returns:     The number of groups found. 
 *
 * Just a wrapper around kauth_cred_getgroups to handle the case of a server supporting less
 * than NGROUPS. 
 */
static int
get_auxiliary_groups(kauth_cred_t cred, gid_t groups[NGROUPS], int count)
{
        gid_t pgid;
        int maxcount = count < NGROUPS ? count + 1 : NGROUPS;
        int i;
        
        for (i = 0; i < NGROUPS; i++)
                groups[i] = -2; /* Initialize to the nobody group */

        (void)kauth_cred_getgroups(cred, groups, &maxcount);
        if (maxcount < 1)
                return (maxcount);
        
        /*
         * kauth_get_groups returns the primary group followed by the
         * users auxiliary groups. If the number of groups the server supports
         * is less than NGROUPS, then we will drop the first group so that
         * we can send one more group over the wire.
         */


        if (count < NGROUPS) {
                pgid = kauth_cred_getgid(cred);
                if (pgid == groups[0]) {
                        maxcount -= 1;
                        for (i = 0;  i < maxcount; i++) {
                                groups[i] = groups[i+1];
                        }
                }
        }
        
        return (maxcount);
}

int
nfsm_rpchead2(struct nfsmount *nmp, int sotype, int prog, int vers, int proc, int auth_type,
        kauth_cred_t cred, struct nfsreq *req, mbuf_t mrest, u_int64_t *xidp, mbuf_t *mreqp)
{
        mbuf_t mreq, mb;
        int error, i, auth_len = 0, authsiz, reqlen;
        size_t headlen;
        struct nfsm_chain nmreq;
        gid_t grouplist[NGROUPS];
        int groupcount;

        /* calculate expected auth length */
        switch (auth_type) {
                case RPCAUTH_NONE:
                        auth_len = 0;
                        break;
                case RPCAUTH_SYS:
                    {
                        int count = nmp->nm_numgrps < NGROUPS ? nmp->nm_numgrps : NGROUPS;

                        if (!cred)
                                return (EINVAL);
                        groupcount = get_auxiliary_groups(cred, grouplist, count);
                        if (groupcount < 0)
                                return (EINVAL);
                        auth_len = ((uint32_t)groupcount + 5) * NFSX_UNSIGNED;
                        break;
                    }
                case RPCAUTH_KRB5:
                case RPCAUTH_KRB5I:
                case RPCAUTH_KRB5P:
                        if (!req || !cred)
                                return (EINVAL);
                        auth_len = 5 * NFSX_UNSIGNED + 0; // zero context handle for now
                        break;
                default:
                        return (EINVAL);
                }
        authsiz = nfsm_rndup(auth_len);

        /* allocate the packet */
        headlen = authsiz + 10 * NFSX_UNSIGNED;
        if (sotype == SOCK_STREAM) /* also include room for any RPC Record Mark */
                headlen += NFSX_UNSIGNED;
        if (headlen >= nfs_mbuf_minclsize) {
                error = mbuf_getpacket(MBUF_WAITOK, &mreq);
        } else {
                error = mbuf_gethdr(MBUF_WAITOK, MBUF_TYPE_DATA, &mreq);
                if (!error) {
                        if (headlen < nfs_mbuf_mhlen)
                                mbuf_align_32(mreq, headlen);
                        else
                                mbuf_align_32(mreq, 8 * NFSX_UNSIGNED);
                }
        }
        if (error) {
                /* unable to allocate packet */
                /* XXX should we keep statistics for these errors? */
                return (error);
        }

        /*
         * If the caller gave us a non-zero XID then use it because
         * it may be a higher-level resend with a GSSAPI credential.
         * Otherwise, allocate a new one.
         */
        if (*xidp == 0)
                nfs_get_xid(xidp);

        /* build the header(s) */
        nfsm_chain_init(&nmreq, mreq);

        /* First, if it's a TCP stream insert space for an RPC record mark */
        if (sotype == SOCK_STREAM)
                nfsm_chain_add_32(error, &nmreq, 0);

        /* Then the RPC header. */
        nfsm_chain_add_32(error, &nmreq, (*xidp & 0xffffffff));
        nfsm_chain_add_32(error, &nmreq, RPC_CALL);
        nfsm_chain_add_32(error, &nmreq, RPC_VER2);
        nfsm_chain_add_32(error, &nmreq, prog);
        nfsm_chain_add_32(error, &nmreq, vers);
        nfsm_chain_add_32(error, &nmreq, proc);

add_cred:
        switch (auth_type) {
        case RPCAUTH_NONE:
                nfsm_chain_add_32(error, &nmreq, RPCAUTH_NONE); /* auth */
                nfsm_chain_add_32(error, &nmreq, 0);            /* length */
                nfsm_chain_add_32(error, &nmreq, RPCAUTH_NONE); /* verf */
                nfsm_chain_add_32(error, &nmreq, 0);            /* length */
                nfsm_chain_build_done(error, &nmreq);
                /* Append the args mbufs */
                if (!error)
                        error = mbuf_setnext(nmreq.nmc_mcur, mrest);
                break;
        case RPCAUTH_SYS: {
                nfsm_chain_add_32(error, &nmreq, RPCAUTH_SYS);
                nfsm_chain_add_32(error, &nmreq, authsiz);
                nfsm_chain_add_32(error, &nmreq, 0);    /* stamp */
                nfsm_chain_add_32(error, &nmreq, 0);    /* zero-length hostname */
                nfsm_chain_add_32(error, &nmreq, kauth_cred_getuid(cred));      /* UID */
                nfsm_chain_add_32(error, &nmreq, kauth_cred_getgid(cred));      /* GID */
                nfsm_chain_add_32(error, &nmreq, groupcount);/* additional GIDs */
                for (i = 0; i < groupcount; i++)
                        nfsm_chain_add_32(error, &nmreq, grouplist[i]);

                /* And the verifier... */
                nfsm_chain_add_32(error, &nmreq, RPCAUTH_NONE); /* flavor */
                nfsm_chain_add_32(error, &nmreq, 0);            /* length */
                nfsm_chain_build_done(error, &nmreq);

                /* Append the args mbufs */
                if (!error)
                        error = mbuf_setnext(nmreq.nmc_mcur, mrest);
                break;
        }
        case RPCAUTH_KRB5:
        case RPCAUTH_KRB5I:
        case RPCAUTH_KRB5P:
                error = nfs_gss_clnt_cred_put(req, &nmreq, mrest);
                if (error == ENEEDAUTH) {
                        int count = nmp->nm_numgrps < NGROUPS ? nmp->nm_numgrps : NGROUPS;

                        /*
                         * Use sec=sys for this user
                         */
                        error = 0;
                        req->r_auth = auth_type = RPCAUTH_SYS;
                        groupcount = get_auxiliary_groups(cred, grouplist, count);
                        if (groupcount < 0)
                                return (EINVAL);
                        auth_len = ((uint32_t)groupcount + 5) * NFSX_UNSIGNED;
                        authsiz = nfsm_rndup(auth_len);
                        goto add_cred;
                }
                break;
        };

        /* finish setting up the packet */
        if (!error)
                error = mbuf_pkthdr_setrcvif(mreq, 0);

        if (error) {
                mbuf_freem(mreq);
                return (error);
        }

        /* Calculate the size of the request */
        reqlen = 0;
        for (mb = nmreq.nmc_mhead; mb; mb = mbuf_next(mb))
                reqlen += mbuf_len(mb);

        mbuf_pkthdr_setlen(mreq, reqlen);

        /*
         * If the request goes on a TCP stream,
         * set its size in the RPC record mark.
         * The record mark count doesn't include itself
         * and the last fragment bit is set.
         */
        if (sotype == SOCK_STREAM)
                nfsm_chain_set_recmark(error, &nmreq,
                        (reqlen - NFSX_UNSIGNED) | 0x80000000);

        *mreqp = mreq;
        return (0);
}

/*
 * Parse an NFS file attribute structure out of an mbuf chain.
 */
int
nfs_parsefattr(struct nfsm_chain *nmc, int nfsvers, struct nfs_vattr *nvap)
{
        int error = 0;
        enum vtype vtype;
        nfstype nvtype;
        u_short vmode;
        uint32_t val, val2;
        dev_t rdev;

        val = val2 = 0;
        NVATTR_INIT(nvap);

        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_TYPE);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_MODE);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_NUMLINKS);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_OWNER);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_OWNER_GROUP);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_SIZE);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_SPACE_USED);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_RAWDEV);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_FSID);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_FILEID);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_TIME_ACCESS);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_TIME_MODIFY);
        NFS_BITMAP_SET(nvap->nva_bitmap, NFS_FATTR_TIME_METADATA);

        nfsm_chain_get_32(error, nmc, nvtype);
        nfsm_chain_get_32(error, nmc, vmode);
        nfsmout_if(error);

        if (nfsvers == NFS_VER3) {
                nvap->nva_type = vtype = nfstov_type(nvtype, nfsvers);
        } else {
                /*
                 * The duplicate information returned in fa_type and fa_mode
                 * is an ambiguity in the NFS version 2 protocol.
                 *
                 * VREG should be taken literally as a regular file.  If a
                 * server intends to return some type information differently
                 * in the upper bits of the mode field (e.g. for sockets, or
                 * FIFOs), NFSv2 mandates fa_type to be VNON.  Anyway, we
                 * leave the examination of the mode bits even in the VREG
                 * case to avoid breakage for bogus servers, but we make sure
                 * that there are actually type bits set in the upper part of
                 * fa_mode (and failing that, trust the va_type field).
                 *
                 * NFSv3 cleared the issue, and requires fa_mode to not
                 * contain any type information (while also introducing
                 * sockets and FIFOs for fa_type).
                 */
                vtype = nfstov_type(nvtype, nfsvers);
                if ((vtype == VNON) || ((vtype == VREG) && ((vmode & S_IFMT) != 0)))
                        vtype = IFTOVT(vmode);
                nvap->nva_type = vtype;
        }

        nvap->nva_mode = (vmode & 07777);

        nfsm_chain_get_32(error, nmc, nvap->nva_nlink);
        nfsm_chain_get_32(error, nmc, nvap->nva_uid);
        nfsm_chain_get_32(error, nmc, nvap->nva_gid);

        if (nfsvers == NFS_VER3) {
                nfsm_chain_get_64(error, nmc, nvap->nva_size);
                nfsm_chain_get_64(error, nmc, nvap->nva_bytes);
                nfsm_chain_get_32(error, nmc, nvap->nva_rawdev.specdata1);
                nfsm_chain_get_32(error, nmc, nvap->nva_rawdev.specdata2);
                nfsmout_if(error);
                nfsm_chain_get_64(error, nmc, nvap->nva_fsid.major);
                nvap->nva_fsid.minor = 0;
                nfsm_chain_get_64(error, nmc, nvap->nva_fileid);
        } else {
                nfsm_chain_get_32(error, nmc, nvap->nva_size);
                nfsm_chain_adv(error, nmc, NFSX_UNSIGNED);
                nfsm_chain_get_32(error, nmc, rdev);
                nfsmout_if(error);
                nvap->nva_rawdev.specdata1 = major(rdev);
                nvap->nva_rawdev.specdata2 = minor(rdev);
                nfsm_chain_get_32(error, nmc, val); /* blocks */
                nfsmout_if(error);
                nvap->nva_bytes = val * NFS_FABLKSIZE;
                nfsm_chain_get_32(error, nmc, val);
                nfsmout_if(error);
                nvap->nva_fsid.major = (uint64_t)val;
                nvap->nva_fsid.minor = 0;
                nfsm_chain_get_32(error, nmc, val);
                nfsmout_if(error);
                nvap->nva_fileid = (uint64_t)val;
                /* Really ugly NFSv2 kludge. */
                if ((vtype == VCHR) && (rdev == (dev_t)0xffffffff))
                        nvap->nva_type = VFIFO;
        }
        nfsm_chain_get_time(error, nmc, nfsvers,
                nvap->nva_timesec[NFSTIME_ACCESS],
                nvap->nva_timensec[NFSTIME_ACCESS]);
        nfsm_chain_get_time(error, nmc, nfsvers,
                nvap->nva_timesec[NFSTIME_MODIFY],
                nvap->nva_timensec[NFSTIME_MODIFY]);
        nfsm_chain_get_time(error, nmc, nfsvers,
                nvap->nva_timesec[NFSTIME_CHANGE],
                nvap->nva_timensec[NFSTIME_CHANGE]);
nfsmout:
        return (error);
}

/*
 * Load the attribute cache (that lives in the nfsnode entry) with
 * the value pointed to by nvap, unless the file type in the attribute
 * cache doesn't match the file type in the nvap, in which case log a
 * warning and return ESTALE.
 *
 * If the dontshrink flag is set, then it's not safe to call ubc_setsize()
 * to shrink the size of the file.
 */
int
nfs_loadattrcache(
        nfsnode_t np,
        struct nfs_vattr *nvap,
        u_int64_t *xidp,
        int dontshrink)
{
        mount_t mp;
        vnode_t vp;
        struct timeval now;
        struct nfs_vattr *npnvap;
        int xattr = np->n_vattr.nva_flags & NFS_FFLAG_IS_ATTR;
        int referral = np->n_vattr.nva_flags & NFS_FFLAG_TRIGGER_REFERRAL;
        int aclbit, monitored, error = 0;
        kauth_acl_t acl;
        struct nfsmount *nmp;
        uint32_t events = np->n_events;

        if (np->n_hflag & NHINIT) {
                vp = NULL;
                mp = np->n_mount;
        } else {
                vp = NFSTOV(np);
                mp = vnode_mount(vp);
        }
        monitored = vp ? vnode_ismonitored(vp) : 0;

        FSDBG_TOP(527, np, vp, *xidp >> 32, *xidp);

        if (!((nmp = VFSTONFS(mp)))) {
                FSDBG_BOT(527, ENXIO, 1, 0, *xidp);
                return (ENXIO);
        }

        if (*xidp < np->n_xid) {
                /*
                 * We have already updated attributes with a response from
                 * a later request.  The attributes we have here are probably
                 * stale so we drop them (just return).  However, our
                 * out-of-order receipt could be correct - if the requests were
                 * processed out of order at the server.  Given the uncertainty
                 * we invalidate our cached attributes.  *xidp is zeroed here
                 * to indicate the attributes were dropped - only getattr
                 * cares - it needs to retry the rpc.
                 */
                NATTRINVALIDATE(np);
                FSDBG_BOT(527, 0, np, np->n_xid, *xidp);
                *xidp = 0;
                return (0);
        }

        if (vp && (nvap->nva_type != vnode_vtype(vp))) {
                /*
                 * The filehandle has changed type on us.  This can be
                 * caused by either the server not having unique filehandles
                 * or because another client has removed the previous
                 * filehandle and a new object (of a different type)
                 * has been created with the same filehandle.
                 *
                 * We can't simply switch the type on the vnode because
                 * there may be type-specific fields that need to be
                 * cleaned up or set up.
                 *
                 * So, what should we do with this vnode?
                 *
                 * About the best we can do is log a warning and return
                 * an error.  ESTALE is about the closest error, but it
                 * is a little strange that we come up with this error
                 * internally instead of simply passing it through from
                 * the server.  Hopefully, the vnode will be reclaimed
                 * soon so the filehandle can be reincarnated as the new
                 * object type.
                 */
                printf("nfs loadattrcache vnode changed type, was %d now %d\n",
                        vnode_vtype(vp), nvap->nva_type);
                error = ESTALE;
                if (monitored)
                        events |= VNODE_EVENT_DELETE;
                goto out;
        }

        npnvap = &np->n_vattr;

        /*
         * The ACL cache needs special handling because it is not
         * always updated.  Save current ACL cache state so it can
         * be restored after copying the new attributes into place.
         */
        aclbit = NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_ACL);
        acl = npnvap->nva_acl;

        if (monitored) {
                /*
                 * For monitored nodes, check for attribute changes that should generate events.
                 */
                if (NFS_BITMAP_ISSET(nvap->nva_bitmap, NFS_FATTR_NUMLINKS) &&
                    (nvap->nva_nlink != npnvap->nva_nlink))
                        events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_LINK;
                if (events & VNODE_EVENT_PERMS)
                        /* no need to do all the checking if it's already set */;
                else if (NFS_BITMAP_ISSET(nvap->nva_bitmap, NFS_FATTR_MODE) &&
                         (nvap->nva_mode != npnvap->nva_mode))
                        events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_PERMS;
                else if (NFS_BITMAP_ISSET(nvap->nva_bitmap, NFS_FATTR_OWNER) &&
                         (nvap->nva_uid != npnvap->nva_uid))
                        events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_PERMS;
                else if (NFS_BITMAP_ISSET(nvap->nva_bitmap, NFS_FATTR_OWNER_GROUP) &&
                         (nvap->nva_gid != npnvap->nva_gid))
                        events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_PERMS;
                else if (nmp->nm_vers >= NFS_VER4) {
                        if (NFS_BITMAP_ISSET(nvap->nva_bitmap, NFS_FATTR_OWNER) &&
                            !kauth_guid_equal(&nvap->nva_uuuid, &npnvap->nva_uuuid))
                                events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_PERMS;
                        else if (NFS_BITMAP_ISSET(nvap->nva_bitmap, NFS_FATTR_OWNER_GROUP) &&
                                 !kauth_guid_equal(&nvap->nva_guuid, &npnvap->nva_guuid))
                                events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_PERMS;
                        else if ((NFS_BITMAP_ISSET(nvap->nva_bitmap, NFS_FATTR_ACL) &&
                                 nvap->nva_acl && npnvap->nva_acl &&
                                 ((nvap->nva_acl->acl_entrycount != npnvap->nva_acl->acl_entrycount) ||
                                  bcmp(nvap->nva_acl, npnvap->nva_acl, KAUTH_ACL_COPYSIZE(nvap->nva_acl)))))
                                events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_PERMS;
                }
                if (((nmp->nm_vers >= NFS_VER4) && (nvap->nva_change != npnvap->nva_change)) ||
                   (NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_TIME_MODIFY) &&
                    ((nvap->nva_timesec[NFSTIME_MODIFY] != npnvap->nva_timesec[NFSTIME_MODIFY]) ||
                     (nvap->nva_timensec[NFSTIME_MODIFY] != npnvap->nva_timensec[NFSTIME_MODIFY]))))
                        events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_WRITE;
                if (!events && NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_RAWDEV) &&
                    ((nvap->nva_rawdev.specdata1 != npnvap->nva_rawdev.specdata1) ||
                     (nvap->nva_rawdev.specdata2 != npnvap->nva_rawdev.specdata2)))
                        events |= VNODE_EVENT_ATTRIB;
                if (!events && NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_FILEID) &&
                    (nvap->nva_fileid != npnvap->nva_fileid))
                        events |= VNODE_EVENT_ATTRIB;
                if (!events && NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_ARCHIVE) &&
                    ((nvap->nva_flags & NFS_FFLAG_ARCHIVED) != (npnvap->nva_flags & NFS_FFLAG_ARCHIVED)))
                        events |= VNODE_EVENT_ATTRIB;
                if (!events && NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_HIDDEN) &&
                    ((nvap->nva_flags & NFS_FFLAG_HIDDEN) != (npnvap->nva_flags & NFS_FFLAG_HIDDEN)))
                        events |= VNODE_EVENT_ATTRIB;
                if (!events && NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_TIME_CREATE) &&
                    ((nvap->nva_timesec[NFSTIME_CREATE] != npnvap->nva_timesec[NFSTIME_CREATE]) ||
                     (nvap->nva_timensec[NFSTIME_CREATE] != npnvap->nva_timensec[NFSTIME_CREATE])))
                        events |= VNODE_EVENT_ATTRIB;
                if (!events && NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_TIME_BACKUP) &&
                    ((nvap->nva_timesec[NFSTIME_BACKUP] != npnvap->nva_timesec[NFSTIME_BACKUP]) ||
                     (nvap->nva_timensec[NFSTIME_BACKUP] != npnvap->nva_timensec[NFSTIME_BACKUP])))
                        events |= VNODE_EVENT_ATTRIB;
        }

        /* Copy the attributes to the attribute cache */
        bcopy((caddr_t)nvap, (caddr_t)npnvap, sizeof(*nvap));

        microuptime(&now);
        np->n_attrstamp = now.tv_sec;
        np->n_xid = *xidp;
        /* NFS_FFLAG_IS_ATTR and NFS_FFLAG_TRIGGER_REFERRAL need to be sticky... */
        if (vp && xattr)
                nvap->nva_flags |= xattr;
        if (vp && referral)
                nvap->nva_flags |= referral;

        if (NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_ACL)) {
                /* we're updating the ACL */
                if (nvap->nva_acl) {
                        /* make a copy of the acl for the cache */
                        npnvap->nva_acl = kauth_acl_alloc(nvap->nva_acl->acl_entrycount);
                        if (npnvap->nva_acl) {
                                bcopy(nvap->nva_acl, npnvap->nva_acl, KAUTH_ACL_COPYSIZE(nvap->nva_acl));
                        } else {
                                /* can't make a copy to cache, invalidate ACL cache */
                                NFS_BITMAP_CLR(npnvap->nva_bitmap, NFS_FATTR_ACL);
                                NACLINVALIDATE(np);
                                aclbit = 0;
                        }
                }
                if (acl) {
                        kauth_acl_free(acl);
                        acl = NULL;
                }
        }
        if (NFS_BITMAP_ISSET(npnvap->nva_bitmap, NFS_FATTR_ACL)) {
                /* update the ACL timestamp */
                np->n_aclstamp = now.tv_sec;
        } else {
                /* we aren't updating the ACL, so restore original values */
                if (aclbit)
                        NFS_BITMAP_SET(npnvap->nva_bitmap, NFS_FATTR_ACL);
                npnvap->nva_acl = acl;
        }

#if CONFIG_TRIGGERS
        /*
         * For NFSv4, if the fsid doesn't match the fsid for the mount, then
         * this node is for a different file system on the server.  So we mark
         * this node as a trigger node that will trigger the mirror mount.
         */
        if ((nmp->nm_vers >= NFS_VER4) && (nvap->nva_type == VDIR) &&
            ((np->n_vattr.nva_fsid.major != nmp->nm_fsid.major) ||
             (np->n_vattr.nva_fsid.minor != nmp->nm_fsid.minor)))
                np->n_vattr.nva_flags |= NFS_FFLAG_TRIGGER;
#endif

        if (!vp || (nvap->nva_type != VREG)) {
                np->n_size = nvap->nva_size;
        } else if (nvap->nva_size != np->n_size) {
                FSDBG(527, np, nvap->nva_size, np->n_size, (nvap->nva_type == VREG) | (np->n_flag & NMODIFIED ? 6 : 4));
                if (!UBCINFOEXISTS(vp) || (dontshrink && (nvap->nva_size < np->n_size))) {
                        /* asked not to shrink, so stick with current size */
                        FSDBG(527, np, np->n_size, np->n_vattr.nva_size, 0xf00d0001);
                        nvap->nva_size = np->n_size;
                        NATTRINVALIDATE(np);
                } else if ((np->n_flag & NMODIFIED) && (nvap->nva_size < np->n_size)) {
                        /* if we've modified, stick with larger size */
                        FSDBG(527, np, np->n_size, np->n_vattr.nva_size, 0xf00d0002);
                        nvap->nva_size = np->n_size;
                        npnvap->nva_size = np->n_size;
                } else {
                        /*
                         * n_size is protected by the data lock, so we need to
                         * defer updating it until it's safe.  We save the new size
                         * and set a flag and it'll get updated the next time we get/drop
                         * the data lock or the next time we do a getattr.
                         */
                        np->n_newsize = nvap->nva_size;
                        SET(np->n_flag, NUPDATESIZE);
                        if (monitored)
                                events |= VNODE_EVENT_ATTRIB | VNODE_EVENT_EXTEND;
                }
        }

        if (np->n_flag & NCHG) {
                if (np->n_flag & NACC) {
                        nvap->nva_timesec[NFSTIME_ACCESS] = np->n_atim.tv_sec;
                        nvap->nva_timensec[NFSTIME_ACCESS] = np->n_atim.tv_nsec;
                }
                if (np->n_flag & NUPD) {
                        nvap->nva_timesec[NFSTIME_MODIFY] = np->n_mtim.tv_sec;
                        nvap->nva_timensec[NFSTIME_MODIFY] = np->n_mtim.tv_nsec;
                }
        }

out:
        if (monitored && events)
                nfs_vnode_notify(np, events);
        FSDBG_BOT(527, error, np, np->n_size, *xidp);
        return (error);
}

/*
 * Calculate the attribute timeout based on
 * how recently the file has been modified.
 */
int
nfs_attrcachetimeout(nfsnode_t np)
{
        struct nfsmount *nmp;
        struct timeval now;
        int isdir;
        uint32_t timeo;

        nmp = NFSTONMP(np);
        if (nfs_mount_gone(nmp))
                return (0);

        isdir = vnode_isdir(NFSTOV(np));

        if ((nmp->nm_vers >= NFS_VER4) && (np->n_openflags & N_DELEG_MASK)) {
                /* If we have a delegation, we always use the max timeout. */
                timeo = isdir ? nmp->nm_acdirmax : nmp->nm_acregmax;
        } else if ((np)->n_flag & NMODIFIED) {
                /* If we have modifications, we always use the min timeout. */
                timeo = isdir ? nmp->nm_acdirmin : nmp->nm_acregmin;
        } else {
                /* Otherwise, we base the timeout on how old the file seems. */
                /* Note that if the client and server clocks are way out of sync, */
                /* timeout will probably get clamped to a min or max value */
                microtime(&now);
                timeo = (now.tv_sec - (np)->n_vattr.nva_timesec[NFSTIME_MODIFY]) / 10;
                if (isdir) {
                        if (timeo < nmp->nm_acdirmin)
                                timeo = nmp->nm_acdirmin;
                        else if (timeo > nmp->nm_acdirmax)
                                timeo = nmp->nm_acdirmax;
                } else {
                        if (timeo < nmp->nm_acregmin)
                                timeo = nmp->nm_acregmin;
                        else if (timeo > nmp->nm_acregmax)
                                timeo = nmp->nm_acregmax;
                }
        }

        return (timeo);
}

/*
 * Check the attribute cache time stamp.
 * If the cache is valid, copy contents to *nvaper and return 0
 * otherwise return an error.
 * Must be called with the node locked.
 */
int
nfs_getattrcache(nfsnode_t np, struct nfs_vattr *nvaper, int flags)
{
        struct nfs_vattr *nvap;
        struct timeval nowup;
        int32_t timeo;
        struct nfsmount *nmp;

        /* Check if the attributes are valid. */
        if (!NATTRVALID(np) || ((flags & NGA_ACL) && !NACLVALID(np))) {
                FSDBG(528, np, 0, 0xffffff01, ENOENT);
                OSAddAtomic64(1, &nfsstats.attrcache_misses);
                return (ENOENT);
        }

        nmp = NFSTONMP(np);
        if (nfs_mount_gone(nmp))
                return (ENXIO);
        /*
         * Verify the cached attributes haven't timed out.
         * If the server isn't responding, skip the check
         * and return cached attributes.
         */
        if (!nfs_use_cache(nmp)) {
                timeo = nfs_attrcachetimeout(np);
                microuptime(&nowup);
                if ((nowup.tv_sec - np->n_attrstamp) >= timeo) {
                        FSDBG(528, np, 0, 0xffffff02, ENOENT);
                        OSAddAtomic64(1, &nfsstats.attrcache_misses);
                        return (ENOENT);
                }
                if ((flags & NGA_ACL) && ((nowup.tv_sec - np->n_aclstamp) >= timeo)) {
                        FSDBG(528, np, 0, 0xffffff02, ENOENT);
                        OSAddAtomic64(1, &nfsstats.attrcache_misses);
                        return (ENOENT);
                }
        }

        nvap = &np->n_vattr;
        FSDBG(528, np, nvap->nva_size, np->n_size, 0xcace);
        OSAddAtomic64(1, &nfsstats.attrcache_hits);

        if (nvap->nva_type != VREG) {
                np->n_size = nvap->nva_size;
        } else if (nvap->nva_size != np->n_size) {
                FSDBG(528, np, nvap->nva_size, np->n_size, (nvap->nva_type == VREG) | (np->n_flag & NMODIFIED ? 6 : 4));
                if ((np->n_flag & NMODIFIED) && (nvap->nva_size < np->n_size)) {
                        /* if we've modified, stick with larger size */
                        nvap->nva_size = np->n_size;
                } else {
                        /*
                         * n_size is protected by the data lock, so we need to
                         * defer updating it until it's safe.  We save the new size
                         * and set a flag and it'll get updated the next time we get/drop
                         * the data lock or the next time we do a getattr.
                         */
                        np->n_newsize = nvap->nva_size;
                        SET(np->n_flag, NUPDATESIZE);
                }
        }

        bcopy((caddr_t)nvap, (caddr_t)nvaper, sizeof(struct nfs_vattr));
        if (np->n_flag & NCHG) {
                if (np->n_flag & NACC) {
                        nvaper->nva_timesec[NFSTIME_ACCESS] = np->n_atim.tv_sec;
                        nvaper->nva_timensec[NFSTIME_ACCESS] = np->n_atim.tv_nsec;
                }
                if (np->n_flag & NUPD) {
                        nvaper->nva_timesec[NFSTIME_MODIFY] = np->n_mtim.tv_sec;
                        nvaper->nva_timensec[NFSTIME_MODIFY] = np->n_mtim.tv_nsec;
                }
        }
        if (nvap->nva_acl) {
                if (flags & NGA_ACL) {
                        nvaper->nva_acl = kauth_acl_alloc(nvap->nva_acl->acl_entrycount);
                        if (!nvaper->nva_acl)
                                return (ENOMEM);
                        bcopy(nvap->nva_acl, nvaper->nva_acl, KAUTH_ACL_COPYSIZE(nvap->nva_acl));
                } else {
                        nvaper->nva_acl = NULL;
                }
        }
        return (0);
}

/*
 * When creating file system objects:
 * Don't bother setting UID if it's the same as the credential performing the create.
 * Don't bother setting GID if it's the same as the directory or credential.
 */
void
nfs_avoid_needless_id_setting_on_create(nfsnode_t dnp, struct vnode_attr *vap, vfs_context_t ctx)
{
        if (VATTR_IS_ACTIVE(vap, va_uid)) {
                if (kauth_cred_getuid(vfs_context_ucred(ctx)) == vap->va_uid) {
                        VATTR_CLEAR_ACTIVE(vap, va_uid);
                        VATTR_CLEAR_ACTIVE(vap, va_uuuid);
                }
        }
        if (VATTR_IS_ACTIVE(vap, va_gid)) {
                if ((vap->va_gid == dnp->n_vattr.nva_gid) ||
                    (kauth_cred_getgid(vfs_context_ucred(ctx)) == vap->va_gid)) {
                        VATTR_CLEAR_ACTIVE(vap, va_gid);
                        VATTR_CLEAR_ACTIVE(vap, va_guuid);
                }
        }
}

/*
 * Convert a universal address string to a sockaddr structure.
 *
 * Universal addresses can be in the following formats:
 *
 * d = decimal (IPv4)
 * x = hexadecimal (IPv6)
 * p = port (decimal)
 *
 * d.d.d.d
 * d.d.d.d.p.p
 * x:x:x:x:x:x:x:x
 * x:x:x:x:x:x:x:x.p.p
 * x:x:x:x:x:x:d.d.d.d
 * x:x:x:x:x:x:d.d.d.d.p.p
 *
 * IPv6 strings can also have a series of zeroes elided
 * IPv6 strings can also have a %scope suffix at the end (after any port)
 *
 * rules & exceptions:
 * - value before : is hex
 * - value before . is dec
 * - once . hit, all values are dec
 * - hex+port case means value before first dot is actually hex
 * - . is always preceded by digits except if last hex was double-colon
 *
 * scan, converting #s to bytes
 * first time a . is encountered, scan the rest to count them.
 * 2 dots = just port
 * 3 dots = just IPv4 no port
 * 5 dots = IPv4 and port
 */

#define IS_DIGIT(C) \
        (((C) >= '0') && ((C) <= '9'))

#define IS_XDIGIT(C) \
        (IS_DIGIT(C) || \
         (((C) >= 'A') && ((C) <= 'F')) || \
         (((C) >= 'a') && ((C) <= 'f')))

int
nfs_uaddr2sockaddr(const char *uaddr, struct sockaddr *addr)
{
        const char *p, *pd;     /* pointers to current character in scan */
        const char *pnum;       /* pointer to current number to decode */
        const char *pscope;     /* pointer to IPv6 scope ID */
        uint8_t a[18];          /* octet array to store address bytes */
        int i;                  /* index of next octet to decode */
        int dci;                /* index of octet to insert double-colon zeroes */
        int dcount, xdcount;    /* count of digits in current number */
        int needmore;           /* set when we know we need more input (e.g. after colon, period) */
        int dots;               /* # of dots */
        int hex;                /* contains hex values */
        unsigned long val;      /* decoded value */
        int s;                  /* index used for sliding array to insert elided zeroes */

#define HEXVALUE        0
#define DECIMALVALUE    1
#define GET(TYPE) \
        do { \
                if ((dcount <= 0) || (dcount > (((TYPE) == DECIMALVALUE) ? 3 : 4))) \
                        return (0); \
                if (((TYPE) == DECIMALVALUE) && xdcount) \
                        return (0); \
                val = strtoul(pnum, NULL, ((TYPE) == DECIMALVALUE) ? 10 : 16); \
                if (((TYPE) == DECIMALVALUE) && (val >= 256)) \
                        return (0); \
                /* check if there is room left in the array */ \
                if (i > (int)(sizeof(a) - (((TYPE) == HEXVALUE) ? 2 : 1) - ((dci != -1) ? 2 : 0))) \
                        return (0); \
                if ((TYPE) == HEXVALUE) \
                        a[i++] = ((val >> 8) & 0xff); \
                a[i++] = (val & 0xff); \
        } while (0)

        hex = 0;
        dots = 0;
        dci = -1;
        i = dcount = xdcount = 0;
        pnum = p = uaddr;
        pscope = NULL;
        needmore = 1;
        if ((*p == ':') && (*++p != ':')) /* if it starts with colon, gotta be a double */
                return (0);

        while (*p) {
                if (IS_XDIGIT(*p)) {
                        dcount++;
                        if (!IS_DIGIT(*p))
                                xdcount++;
                        needmore = 0;
                        p++;
                } else if (*p == '.') {
                        /* rest is decimal IPv4 dotted quad and/or port */
                        if (!dots) {
                                /* this is the first, so count them */
                                for (pd = p; *pd; pd++) {
                                        if (*pd == '.') {
                                                if (++dots > 5)
                                                        return (0);
                                        } else if (hex && (*pd == '%')) {
                                                break;
                                        } else if ((*pd < '0') || (*pd > '9')) {
                                                return (0);
                                        }
                                }
                                if ((dots != 2) && (dots != 3) && (dots != 5))
                                        return (0);
                                if (hex && (dots == 2)) { /* hex+port */
                                        if (!dcount && needmore)
                                                return (0);
                                        if (dcount) /* last hex may be elided zero */
                                                GET(HEXVALUE);
                                } else {
                                        GET(DECIMALVALUE);
                                }
                        } else {
                                GET(DECIMALVALUE);
                        }
                        dcount = xdcount = 0;
                        needmore = 1;
                        pnum = ++p;
                } else if (*p == ':') {
                        hex = 1;
                        if (dots)
                                return (0);
                        if (!dcount) { /* missing number, probably double colon */
                                if (dci >= 0) /* can only have one double colon */
                                        return (0);
                                dci = i;
                                needmore = 0;
                        } else {
                                GET(HEXVALUE);
                                dcount = xdcount = 0;
                                needmore = 1;
                        }
                        pnum = ++p;
                } else if (*p == '%') { /* scope ID delimiter */
                        if (!hex)
                                return (0);
                        p++;
                        pscope = p;
                        break;
                } else { /* unexpected character */
                        return (0);
                }
        }
        if (needmore && !dcount)
                return (0);
        if (dcount) /* decode trailing number */
                GET(dots ? DECIMALVALUE : HEXVALUE);
        if (dci >= 0) {  /* got a double-colon at i, need to insert a range of zeroes */
                /* if we got a port, slide to end of array */
                /* otherwise, slide to end of address (non-port) values */
                int end = ((dots == 2) || (dots == 5)) ? sizeof(a) : (sizeof(a) - 2);
                if (i % 2) /* length of zero range must be multiple of 2 */
                        return (0);
                if (i >= end) /* no room? */
                        return (0);
                /* slide (i-dci) numbers up from index dci */
                for (s=0; s < (i - dci); s++)
                        a[end-1-s] = a[i-1-s];
                /* zero (end-i) numbers at index dci */
                for (s=0; s < (end - i); s++)
                        a[dci+s] = 0;
                i = end;
        }

        /* copy out resulting socket address */
        if (hex) {
                struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)addr;
                if ((((dots == 0) || (dots == 3)) && (i != (sizeof(a)-2))))
                        return (0);
                if ((((dots == 2) || (dots == 5)) && (i != sizeof(a))))
                        return (0);
                bzero(sin6, sizeof(struct sockaddr_in6));
                sin6->sin6_len = sizeof(struct sockaddr_in6);
                sin6->sin6_family = AF_INET6;
                bcopy(a, &sin6->sin6_addr.s6_addr, sizeof(struct in6_addr));
                if ((dots == 5) || (dots == 2))
                        sin6->sin6_port = htons((a[16] << 8) | a[17]);
                if (pscope) {
                        for (p=pscope; IS_DIGIT(*p); p++)
                                ;
                        if (*p && !IS_DIGIT(*p)) { /* name */
                                ifnet_t interface = NULL;
                                if (ifnet_find_by_name(pscope, &interface) == 0)
                                        sin6->sin6_scope_id = ifnet_index(interface);
                                if (interface)
                                        ifnet_release(interface);
                        } else { /* decimal number */
                                sin6->sin6_scope_id = strtoul(pscope, NULL, 10);
                        }
                        /* XXX should we also embed scope id for linklocal? */
                }
        } else {
                struct sockaddr_in *sin = (struct sockaddr_in*)addr;
                if ((dots != 3) && (dots != 5))
                        return (0);
                if ((dots == 3) && (i != 4))
                        return (0);
                if ((dots == 5) && (i != 6))
                        return (0);
                bzero(sin, sizeof(struct sockaddr_in));
                sin->sin_len = sizeof(struct sockaddr_in);
                sin->sin_family = AF_INET;
                bcopy(a, &sin->sin_addr.s_addr, sizeof(struct in_addr));
                if (dots == 5)
                        sin->sin_port = htons((a[4] << 8) | a[5]);
        }
        return (1);
}


/* NFS Client debugging support */
uint32_t nfs_debug_ctl;

#include <libkern/libkern.h>
#include <stdarg.h>

void
nfs_printf(int facility, int level, const char *fmt, ...)
{
        va_list ap;
        
        if ((uint32_t)level > NFS_DEBUG_LEVEL)
                return;
        if (NFS_DEBUG_FACILITY && !((uint32_t)facility & NFS_DEBUG_FACILITY))
                return;
        
        va_start(ap, fmt);
        vprintf(fmt, ap);
        va_end(ap);
}

/* Is a mount gone away? */
int
nfs_mount_gone(struct nfsmount *nmp)
{
        return (!nmp || vfs_isforce(nmp->nm_mountp) || (nmp->nm_state & (NFSSTA_FORCE | NFSSTA_DEAD)));
}

/*
 * Return some of the more significant mount options
 * as a string, e.g. "'ro,hard,intr,tcp,vers=3,sec=krb5,deadtimeout=0'
 */
int
nfs_mountopts(struct nfsmount *nmp, char *buf, int buflen)
{
        int c;

        c = snprintf(buf, buflen, "%s,%s,%s,%s,vers=%d,sec=%s,%sdeadtimeout=%d",
                (vfs_flags(nmp->nm_mountp) & MNT_RDONLY) ? "ro" : "rw",
                NMFLAG(nmp, SOFT) ? "soft" : "hard",
                NMFLAG(nmp, INTR) ? "intr" : "nointr",
                nmp->nm_sotype == SOCK_STREAM ? "tcp" : "udp",
                nmp->nm_vers,
                nmp->nm_auth == RPCAUTH_KRB5  ? "krb5" :
                nmp->nm_auth == RPCAUTH_KRB5I ? "krb5i" :
                nmp->nm_auth == RPCAUTH_KRB5P ? "krb5p" :
                nmp->nm_auth == RPCAUTH_SYS   ? "sys" : "none",
                nmp->nm_lockmode == NFS_LOCK_MODE_ENABLED ?  "locks," :
                nmp->nm_lockmode == NFS_LOCK_MODE_DISABLED ? "nolocks," :
                nmp->nm_lockmode == NFS_LOCK_MODE_LOCAL ? "locallocks," : "",
                nmp->nm_deadtimeout);

        return (c > buflen ? ENOMEM : 0);
}

#endif /* NFSCLIENT */

/*
 * Schedule a callout thread to run an NFS timer function
 * interval milliseconds in the future.
 */
void
nfs_interval_timer_start(thread_call_t call, int interval)
{
        uint64_t deadline;

        clock_interval_to_deadline(interval, 1000 * 1000, &deadline);
        thread_call_enter_delayed(call, deadline);
}


#if NFSSERVER

int nfsrv_cmp_secflavs(struct nfs_sec *, struct nfs_sec *);
int nfsrv_hang_addrlist(struct nfs_export *, struct user_nfs_export_args *);
int nfsrv_free_netopt(struct radix_node *, void *);
int nfsrv_free_addrlist(struct nfs_export *, struct user_nfs_export_args *);
struct nfs_export_options *nfsrv_export_lookup(struct nfs_export *, mbuf_t);
struct nfs_export *nfsrv_fhtoexport(struct nfs_filehandle *);
struct nfs_user_stat_node *nfsrv_get_user_stat_node(struct nfs_active_user_list *, struct sockaddr *, uid_t);
void nfsrv_init_user_list(struct nfs_active_user_list *);
void nfsrv_free_user_list(struct nfs_active_user_list *);

/*
 * add NFSv3 WCC data to an mbuf chain
 */
int
nfsm_chain_add_wcc_data_f(
        struct nfsrv_descript *nd,
        struct nfsm_chain *nmc,
        int preattrerr,
        struct vnode_attr *prevap,
        int postattrerr,
        struct vnode_attr *postvap)
{
        int error = 0;

        if (preattrerr) {
                nfsm_chain_add_32(error, nmc, FALSE);
        } else {
                nfsm_chain_add_32(error, nmc, TRUE);
                nfsm_chain_add_64(error, nmc, prevap->va_data_size);
                nfsm_chain_add_time(error, nmc, NFS_VER3, &prevap->va_modify_time);
                nfsm_chain_add_time(error, nmc, NFS_VER3, &prevap->va_change_time);
        }
        nfsm_chain_add_postop_attr(error, nd, nmc, postattrerr, postvap);

        return (error);
}

/*
 * Extract a lookup path from the given mbufs and store it in
 * a newly allocated buffer saved in the given nameidata structure.
 */
int
nfsm_chain_get_path_namei(
        struct nfsm_chain *nmc,
        uint32_t len,
        struct nameidata *nip)
{
        struct componentname *cnp = &nip->ni_cnd;
        int error = 0;
        char *cp;

        if (len > (MAXPATHLEN - 1))
                return (ENAMETOOLONG);

        /*
         * Get a buffer for the name to be translated, and copy the
         * name into the buffer.
         */
        MALLOC_ZONE(cnp->cn_pnbuf, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);
        if (!cnp->cn_pnbuf)
                return (ENOMEM);
        cnp->cn_pnlen = MAXPATHLEN;
        cnp->cn_flags |= HASBUF;

        /* Copy the name from the mbuf list to the string */
        cp = cnp->cn_pnbuf;
        nfsm_chain_get_opaque(error, nmc, len, cp);
        if (error)
                goto out;
        cnp->cn_pnbuf[len] = '\0';

        /* sanity check the string */
        if ((strlen(cp) != len) || strchr(cp, '/'))
                error = EACCES;
out:
        if (error) {
                if (cnp->cn_pnbuf)
                        FREE_ZONE(cnp->cn_pnbuf, MAXPATHLEN, M_NAMEI);
                cnp->cn_flags &= ~HASBUF;
        } else {
                nip->ni_pathlen = len;
        }
        return (error);
}

/*
 * Set up nameidata for a lookup() call and do it.
 */
int
nfsrv_namei(
        struct nfsrv_descript *nd,
        vfs_context_t ctx,
        struct nameidata *nip,
        struct nfs_filehandle *nfhp,
        vnode_t *retdirp,
        struct nfs_export **nxp,
        struct nfs_export_options **nxop)
{
        vnode_t dp;
        int error;
        struct componentname *cnp = &nip->ni_cnd;
        uint32_t cnflags;
        char *tmppn;

        *retdirp = NULL;

        /*
         * Extract and set starting directory.
         */
        error = nfsrv_fhtovp(nfhp, nd, &dp, nxp, nxop);
        if (error)
                goto out;
        error = nfsrv_credcheck(nd, ctx, *nxp, *nxop);
        if (error || (vnode_vtype(dp) != VDIR)) {
                vnode_put(dp);
                error = ENOTDIR;
                goto out;
        }
        *retdirp = dp;

        nip->ni_cnd.cn_context = ctx;

        if (*nxop && ((*nxop)->nxo_flags & NX_READONLY))
                cnp->cn_flags |= RDONLY;

        cnp->cn_flags |= NOCROSSMOUNT;
        cnp->cn_nameptr = cnp->cn_pnbuf;
        nip->ni_usedvp = nip->ni_startdir = dp;

        /*
         * And call lookup() to do the real work
         */
        cnflags = nip->ni_cnd.cn_flags; /* store in case we have to restore */
        while ((error = lookup(nip)) == ERECYCLE) {
                nip->ni_cnd.cn_flags = cnflags;
                cnp->cn_nameptr = cnp->cn_pnbuf;
                nip->ni_usedvp = nip->ni_dvp = nip->ni_startdir = dp;
        }
        if (error)
                goto out;

        /* Check for encountering a symbolic link */
        if (cnp->cn_flags & ISSYMLINK) {
                if (cnp->cn_flags & (LOCKPARENT | WANTPARENT))
                        vnode_put(nip->ni_dvp);
                if (nip->ni_vp) {
                        vnode_put(nip->ni_vp);
                        nip->ni_vp = NULL;
                }
                error = EINVAL;
        }
out:
        if (error) {
                tmppn = cnp->cn_pnbuf;
                cnp->cn_pnbuf = NULL;
                cnp->cn_flags &= ~HASBUF;
                FREE_ZONE(tmppn, cnp->cn_pnlen, M_NAMEI);
        }
        return (error);
}

/*
 * A fiddled version of m_adj() that ensures null fill to a 4-byte
 * boundary and only trims off the back end
 */
void
nfsm_adj(mbuf_t mp, int len, int nul)
{
        mbuf_t m, mnext;
        int count, i, mlen;
        char *cp;

        /*
         * Trim from tail.  Scan the mbuf chain,
         * calculating its length and finding the last mbuf.
         * If the adjustment only affects this mbuf, then just
         * adjust and return.  Otherwise, rescan and truncate
         * after the remaining size.
         */
        count = 0;
        m = mp;
        for (;;) {
                mlen = mbuf_len(m);
                count += mlen;
                mnext = mbuf_next(m);
                if (mnext == NULL)
                        break;
                m = mnext;
        }
        if (mlen > len) {
                mlen -= len;
                mbuf_setlen(m, mlen);
                if (nul > 0) {
                        cp = (caddr_t)mbuf_data(m) + mlen - nul;
                        for (i = 0; i < nul; i++)
                                *cp++ = '\0';
                }
                return;
        }
        count -= len;
        if (count < 0)
                count = 0;
        /*
         * Correct length for chain is "count".
         * Find the mbuf with last data, adjust its length,
         * and toss data from remaining mbufs on chain.
         */
        for (m = mp; m; m = mbuf_next(m)) {
                mlen = mbuf_len(m);
                if (mlen >= count) {
                        mlen = count;
                        mbuf_setlen(m, count);
                        if (nul > 0) {
                                cp = (caddr_t)mbuf_data(m) + mlen - nul;
                                for (i = 0; i < nul; i++)
                                        *cp++ = '\0';
                        }
                        break;
                }
                count -= mlen;
        }
        for (m = mbuf_next(m); m; m = mbuf_next(m))
                mbuf_setlen(m, 0);
}

/*
 * Trim the header out of the mbuf list and trim off any trailing
 * junk so that the mbuf list has only the write data.
 */
int
nfsm_chain_trim_data(struct nfsm_chain *nmc, int len, int *mlen)
{
        int cnt = 0, dlen, adjust;
        caddr_t data;
        mbuf_t m;

        if (mlen)
                *mlen = 0;

        /* trim header */
        for (m = nmc->nmc_mhead; m && (m != nmc->nmc_mcur); m = mbuf_next(m))
                mbuf_setlen(m, 0);
        if (!m)
                return (EIO);

        /* trim current mbuf */
        data = mbuf_data(m);
        dlen = mbuf_len(m);
        adjust = nmc->nmc_ptr - data;
        dlen -= adjust;
        if ((dlen > 0) && (adjust > 0)) {
                if (mbuf_setdata(m, nmc->nmc_ptr, dlen))
                        return(EIO);
        } else
                mbuf_setlen(m, dlen);

        /* skip next len bytes  */
        for (; m && (cnt < len); m = mbuf_next(m)) {
                dlen = mbuf_len(m);
                cnt += dlen;
                if (cnt > len) {
                        /* truncate to end of data */
                        mbuf_setlen(m, dlen - (cnt - len));
                        if (m == nmc->nmc_mcur)
                                nmc->nmc_left -= (cnt - len);
                        cnt = len;
                }
        }
        if (mlen)
                *mlen = cnt;

        /* trim any trailing data */
        if (m == nmc->nmc_mcur)
                nmc->nmc_left = 0;
        for (; m; m = mbuf_next(m))
                mbuf_setlen(m, 0);

        return (0);
}

int
nfsm_chain_add_fattr(
        struct nfsrv_descript *nd,
        struct nfsm_chain *nmc,
        struct vnode_attr *vap)
{
        int error = 0;

        // XXX Should we assert here that all fields are supported?

        nfsm_chain_add_32(error, nmc, vtonfs_type(vap->va_type, nd->nd_vers));
        if (nd->nd_vers == NFS_VER3) {
                nfsm_chain_add_32(error, nmc, vap->va_mode & 07777);
        } else {
                nfsm_chain_add_32(error, nmc, vtonfsv2_mode(vap->va_type, vap->va_mode));
        }
        nfsm_chain_add_32(error, nmc, vap->va_nlink);
        nfsm_chain_add_32(error, nmc, vap->va_uid);
        nfsm_chain_add_32(error, nmc, vap->va_gid);
        if (nd->nd_vers == NFS_VER3) {
                nfsm_chain_add_64(error, nmc, vap->va_data_size);
                nfsm_chain_add_64(error, nmc, vap->va_data_alloc);
                nfsm_chain_add_32(error, nmc, major(vap->va_rdev));
                nfsm_chain_add_32(error, nmc, minor(vap->va_rdev));
                nfsm_chain_add_64(error, nmc, vap->va_fsid);
                nfsm_chain_add_64(error, nmc, vap->va_fileid);
        } else {
                nfsm_chain_add_32(error, nmc, vap->va_data_size);
                nfsm_chain_add_32(error, nmc, NFS_FABLKSIZE);
                if (vap->va_type == VFIFO)
                        nfsm_chain_add_32(error, nmc, 0xffffffff);
                else
                        nfsm_chain_add_32(error, nmc, vap->va_rdev);
                nfsm_chain_add_32(error, nmc, vap->va_data_alloc / NFS_FABLKSIZE);
                nfsm_chain_add_32(error, nmc, vap->va_fsid);
                nfsm_chain_add_32(error, nmc, vap->va_fileid);
        }
        nfsm_chain_add_time(error, nmc, nd->nd_vers, &vap->va_access_time);
        nfsm_chain_add_time(error, nmc, nd->nd_vers, &vap->va_modify_time);
        nfsm_chain_add_time(error, nmc, nd->nd_vers, &vap->va_change_time);

        return (error);
}

int
nfsm_chain_get_sattr(
        struct nfsrv_descript *nd,
        struct nfsm_chain *nmc,
        struct vnode_attr *vap)
{
        int error = 0;
        uint32_t val = 0;
        uint64_t val64 = 0;
        struct timespec now;

        if (nd->nd_vers == NFS_VER2) {
                /*
                 * There is/was a bug in the Sun client that puts 0xffff in the mode
                 * field of sattr when it should put in 0xffffffff.  The u_short
                 * doesn't sign extend.  So check the low order 2 bytes for 0xffff.
                 */
                nfsm_chain_get_32(error, nmc, val);
                if ((val & 0xffff) != 0xffff) {
                        VATTR_SET(vap, va_mode, val & 07777);
                        /* save the "type" bits for NFSv2 create */
                        VATTR_SET(vap, va_type, IFTOVT(val));
                        VATTR_CLEAR_ACTIVE(vap, va_type);
                }
                nfsm_chain_get_32(error, nmc, val);
                if (val != (uint32_t)-1)
                        VATTR_SET(vap, va_uid, val);
                nfsm_chain_get_32(error, nmc, val);
                if (val != (uint32_t)-1)
                        VATTR_SET(vap, va_gid, val);
                /* save the "size" bits for NFSv2 create (even if they appear unset) */
                nfsm_chain_get_32(error, nmc, val);
                VATTR_SET(vap, va_data_size, val);
                if (val == (uint32_t)-1)
                        VATTR_CLEAR_ACTIVE(vap, va_data_size);
                nfsm_chain_get_time(error, nmc, NFS_VER2,
                        vap->va_access_time.tv_sec,
                        vap->va_access_time.tv_nsec);
                if (vap->va_access_time.tv_sec != -1)
                        VATTR_SET_ACTIVE(vap, va_access_time);
                nfsm_chain_get_time(error, nmc, NFS_VER2,
                        vap->va_modify_time.tv_sec,
                        vap->va_modify_time.tv_nsec);
                if (vap->va_modify_time.tv_sec != -1)
                        VATTR_SET_ACTIVE(vap, va_modify_time);
                return (error);
        }

        /* NFSv3 */
        nfsm_chain_get_32(error, nmc, val);
        if (val) {
                nfsm_chain_get_32(error, nmc, val);
                VATTR_SET(vap, va_mode, val & 07777);
        }
        nfsm_chain_get_32(error, nmc, val);
        if (val) {
                nfsm_chain_get_32(error, nmc, val);
                VATTR_SET(vap, va_uid, val);
        }
        nfsm_chain_get_32(error, nmc, val);
        if (val) {
                nfsm_chain_get_32(error, nmc, val);
                VATTR_SET(vap, va_gid, val);
        }
        nfsm_chain_get_32(error, nmc, val);
        if (val) {
                nfsm_chain_get_64(error, nmc, val64);
                VATTR_SET(vap, va_data_size, val64);
        }
        nanotime(&now);
        nfsm_chain_get_32(error, nmc, val);
        switch (val) {
        case NFS_TIME_SET_TO_CLIENT:
                nfsm_chain_get_time(error, nmc, nd->nd_vers,
                        vap->va_access_time.tv_sec,
                        vap->va_access_time.tv_nsec);
                VATTR_SET_ACTIVE(vap, va_access_time);
                vap->va_vaflags &= ~VA_UTIMES_NULL;
                break;
        case NFS_TIME_SET_TO_SERVER:
                VATTR_SET(vap, va_access_time, now);
                vap->va_vaflags |= VA_UTIMES_NULL;
                break;
        }
        nfsm_chain_get_32(error, nmc, val);
        switch (val) {
        case NFS_TIME_SET_TO_CLIENT:
                nfsm_chain_get_time(error, nmc, nd->nd_vers,
                        vap->va_modify_time.tv_sec,
                        vap->va_modify_time.tv_nsec);
                VATTR_SET_ACTIVE(vap, va_modify_time);
                vap->va_vaflags &= ~VA_UTIMES_NULL;
                break;
        case NFS_TIME_SET_TO_SERVER:
                VATTR_SET(vap, va_modify_time, now);
                if (!VATTR_IS_ACTIVE(vap, va_access_time))
                        vap->va_vaflags |= VA_UTIMES_NULL;
                break;
        }

        return (error);
}

/*
 * Compare two security flavor structs
 */
int
nfsrv_cmp_secflavs(struct nfs_sec *sf1, struct nfs_sec *sf2)
{
        int i;

        if (sf1->count != sf2->count)
                return 1;
        for (i = 0; i < sf1->count; i++)
                if (sf1->flavors[i] != sf2->flavors[i])
                        return 1;
        return 0;
}

/*
 * Build hash lists of net addresses and hang them off the NFS export.
 * Called by nfsrv_export() to set up the lists of export addresses.
 */
int
nfsrv_hang_addrlist(struct nfs_export *nx, struct user_nfs_export_args *unxa)
{
        struct nfs_export_net_args nxna;
        struct nfs_netopt *no, *rn_no;
        struct radix_node_head *rnh;
        struct radix_node *rn;
        struct sockaddr *saddr, *smask;
        struct domain *dom;
        int i, error;
        unsigned int net;
        user_addr_t uaddr;
        kauth_cred_t cred;

        uaddr = unxa->nxa_nets;
        for (net = 0; net < unxa->nxa_netcount; net++, uaddr += sizeof(nxna)) {
                error = copyin(uaddr, &nxna, sizeof(nxna));
                if (error)
                        return (error);

                if (nxna.nxna_addr.ss_len > sizeof(struct sockaddr_storage) ||
                    nxna.nxna_mask.ss_len > sizeof(struct sockaddr_storage) ||
                    nxna.nxna_addr.ss_family > AF_MAX ||
                    nxna.nxna_mask.ss_family > AF_MAX)
                        return (EINVAL);

                if (nxna.nxna_flags & (NX_MAPROOT|NX_MAPALL)) {
                        struct posix_cred temp_pcred;
                        bzero(&temp_pcred, sizeof(temp_pcred));
                        temp_pcred.cr_uid = nxna.nxna_cred.cr_uid;
                        temp_pcred.cr_ngroups = nxna.nxna_cred.cr_ngroups;
                        for (i=0; i < nxna.nxna_cred.cr_ngroups && i < NGROUPS; i++)
                                temp_pcred.cr_groups[i] = nxna.nxna_cred.cr_groups[i];
                        cred = posix_cred_create(&temp_pcred);
                        if (!IS_VALID_CRED(cred))
                                return (ENOMEM);
                } else {
                        cred = NOCRED;
                }

                if (nxna.nxna_addr.ss_len == 0) {
                        /* No address means this is a default/world export */
                        if (nx->nx_flags & NX_DEFAULTEXPORT) {
                                if (IS_VALID_CRED(cred))
                                        kauth_cred_unref(&cred);
                                return (EEXIST);
                        }
                        nx->nx_flags |= NX_DEFAULTEXPORT;
                        nx->nx_defopt.nxo_flags = nxna.nxna_flags;
                        nx->nx_defopt.nxo_cred = cred;
                        bcopy(&nxna.nxna_sec, &nx->nx_defopt.nxo_sec, sizeof(struct nfs_sec));
                        nx->nx_expcnt++;
                        continue;
                }

                i = sizeof(struct nfs_netopt);
                i += nxna.nxna_addr.ss_len + nxna.nxna_mask.ss_len;
                MALLOC(no, struct nfs_netopt *, i, M_NETADDR, M_WAITOK);
                if (!no) {
                        if (IS_VALID_CRED(cred))
                                kauth_cred_unref(&cred);
                        return (ENOMEM);
                }
                bzero(no, sizeof(struct nfs_netopt));
                no->no_opt.nxo_flags = nxna.nxna_flags;
                no->no_opt.nxo_cred = cred;
                bcopy(&nxna.nxna_sec, &no->no_opt.nxo_sec, sizeof(struct nfs_sec));

                saddr = (struct sockaddr *)(no + 1);
                bcopy(&nxna.nxna_addr, saddr, nxna.nxna_addr.ss_len);
                if (nxna.nxna_mask.ss_len) {
                        smask = (struct sockaddr *)((caddr_t)saddr + nxna.nxna_addr.ss_len);
                        bcopy(&nxna.nxna_mask, smask, nxna.nxna_mask.ss_len);
                } else {
                        smask = NULL;
                }
                i = saddr->sa_family;
                if ((rnh = nx->nx_rtable[i]) == 0) {
                        /*
                         * Seems silly to initialize every AF when most are not
                         * used, do so on demand here
                         */
                        TAILQ_FOREACH(dom, &domains, dom_entry) {
                                if (dom->dom_family == i && dom->dom_rtattach) {
                                        dom->dom_rtattach((void **)&nx->nx_rtable[i],
                                                dom->dom_rtoffset);
                                        break;
                                }
                        }
                        if ((rnh = nx->nx_rtable[i]) == 0) {
                                if (IS_VALID_CRED(cred))
                                        kauth_cred_unref(&cred);
                                _FREE(no, M_NETADDR);
                                return (ENOBUFS);
                        }
                }
                rn = (*rnh->rnh_addaddr)((caddr_t)saddr, (caddr_t)smask, rnh, no->no_rnodes);
                if (rn == 0) {
                        /*
                         * One of the reasons that rnh_addaddr may fail is that
                         * the entry already exists. To check for this case, we
                         * look up the entry to see if it is there. If so, we
                         * do not need to make a new entry but do continue.
                         *
                         * XXX should this be rnh_lookup() instead?
                         */
                        int matched = 0;
                        rn = (*rnh->rnh_matchaddr)((caddr_t)saddr, rnh);
                        rn_no = (struct nfs_netopt *)rn;
                        if (rn != 0 && (rn->rn_flags & RNF_ROOT) == 0 &&
                            (rn_no->no_opt.nxo_flags == nxna.nxna_flags) &&
                            (!nfsrv_cmp_secflavs(&rn_no->no_opt.nxo_sec, &nxna.nxna_sec))) {
                                kauth_cred_t cred2 = rn_no->no_opt.nxo_cred;
                                if (cred == cred2) {
                                        /* creds are same (or both NULL) */
                                        matched = 1;
                                } else if (cred && cred2 && (kauth_cred_getuid(cred) == kauth_cred_getuid(cred2))) {
                                    /*
                                     * Now compare the effective and
                                     * supplementary groups...
                                     *
                                     * Note: This comparison, as written,
                                     * does not correctly indicate that
                                     * the groups are equivalent, since
                                     * other than the first supplementary
                                     * group, which is also the effective
                                     * group, order on the remaining groups
                                     * doesn't matter, and this is an
                                     * ordered compare.
                                     */
                                    gid_t groups[NGROUPS];
                                    gid_t groups2[NGROUPS];
                                    int groupcount = NGROUPS;
                                    int group2count = NGROUPS;

                                    if (!kauth_cred_getgroups(cred, groups, &groupcount) &&
                                        !kauth_cred_getgroups(cred2, groups2, &group2count) &&
                                        groupcount == group2count) {
                                            for (i=0; i < group2count; i++)
                                                    if (groups[i] != groups2[i])
                                                            break;
                                            if (i >= group2count || i >= NGROUPS)
                                            matched = 1;
                                    }
                                }
                        }
                        if (IS_VALID_CRED(cred))
                                kauth_cred_unref(&cred);
                        _FREE(no, M_NETADDR);
                        if (matched)
                                continue;
                        return (EPERM);
                }
                nx->nx_expcnt++;
        }

        return (0);
}

/*
 * In order to properly track an export's netopt count, we need to pass
 * an additional argument to nfsrv_free_netopt() so that it can decrement
 * the export's netopt count.
 */
struct nfsrv_free_netopt_arg {
        uint32_t *cnt;
        struct radix_node_head *rnh;
};

int
nfsrv_free_netopt(struct radix_node *rn, void *w)
{
        struct nfsrv_free_netopt_arg *fna = (struct nfsrv_free_netopt_arg *)w;
        struct radix_node_head *rnh = fna->rnh;
        uint32_t *cnt = fna->cnt;
        struct nfs_netopt *nno = (struct nfs_netopt *)rn;

        (*rnh->rnh_deladdr)(rn->rn_key, rn->rn_mask, rnh);
        if (IS_VALID_CRED(nno->no_opt.nxo_cred))
                kauth_cred_unref(&nno->no_opt.nxo_cred);
        _FREE((caddr_t)rn, M_NETADDR);
        *cnt -= 1;
        return (0);
}

/*
 * Free the net address hash lists that are hanging off the mount points.
 */
int
nfsrv_free_addrlist(struct nfs_export *nx, struct user_nfs_export_args *unxa)
{
        struct nfs_export_net_args nxna;
        struct radix_node_head *rnh;
        struct radix_node *rn;
        struct nfsrv_free_netopt_arg fna;
        struct nfs_netopt *nno;
        user_addr_t uaddr;
        unsigned int net;
        int i, error;

        if (!unxa || !unxa->nxa_netcount) {
                /* delete everything */
                for (i = 0; i <= AF_MAX; i++)
                        if ( (rnh = nx->nx_rtable[i]) ) {
                                fna.rnh = rnh;
                                fna.cnt = &nx->nx_expcnt;
                                (*rnh->rnh_walktree)(rnh, nfsrv_free_netopt, (caddr_t)&fna);
                                _FREE((caddr_t)rnh, M_RTABLE);
                                nx->nx_rtable[i] = 0;
                        }
                return (0);
        }

        /* delete only the exports specified */
        uaddr = unxa->nxa_nets;
        for (net = 0; net < unxa->nxa_netcount; net++, uaddr += sizeof(nxna)) {
                error = copyin(uaddr, &nxna, sizeof(nxna));
                if (error)
                        return (error);

                if (nxna.nxna_addr.ss_len == 0) {
                        /* No address means this is a default/world export */
                        if (nx->nx_flags & NX_DEFAULTEXPORT) {
                                nx->nx_flags &= ~NX_DEFAULTEXPORT;
                                if (IS_VALID_CRED(nx->nx_defopt.nxo_cred)) {
                                        kauth_cred_unref(&nx->nx_defopt.nxo_cred);
                                }
                                nx->nx_expcnt--;
                        }
                        continue;
                }

                if ((rnh = nx->nx_rtable[nxna.nxna_addr.ss_family]) == 0) {
                        /* AF not initialized? */
                        if (!(unxa->nxa_flags & NXA_ADD))
                                printf("nfsrv_free_addrlist: address not found (0)\n");
                        continue;
                }

                rn = (*rnh->rnh_lookup)(&nxna.nxna_addr,
                        nxna.nxna_mask.ss_len ? &nxna.nxna_mask : NULL, rnh);
                if (!rn || (rn->rn_flags & RNF_ROOT)) {
                        if (!(unxa->nxa_flags & NXA_ADD))
                                printf("nfsrv_free_addrlist: address not found (1)\n");
                        continue;
                }

                (*rnh->rnh_deladdr)(rn->rn_key, rn->rn_mask, rnh);
                nno = (struct nfs_netopt *)rn;
                if (IS_VALID_CRED(nno->no_opt.nxo_cred))
                        kauth_cred_unref(&nno->no_opt.nxo_cred);
                _FREE((caddr_t)rn, M_NETADDR);

                nx->nx_expcnt--;
                if (nx->nx_expcnt == ((nx->nx_flags & NX_DEFAULTEXPORT) ? 1 : 0)) {
                        /* no more entries in rnh, so free it up */
                        _FREE((caddr_t)rnh, M_RTABLE);
                        nx->nx_rtable[nxna.nxna_addr.ss_family] = 0;
                }
        }

        return (0);
}

void enablequotas(struct mount *mp, vfs_context_t ctx); // XXX

int
nfsrv_export(struct user_nfs_export_args *unxa, vfs_context_t ctx)
{
        int error = 0;
        size_t pathlen;
        struct nfs_exportfs *nxfs, *nxfs2, *nxfs3;
        struct nfs_export *nx, *nx2, *nx3;
        struct nfs_filehandle nfh;
        struct nameidata mnd, xnd;
        vnode_t mvp = NULL, xvp = NULL;
        mount_t mp = NULL;
        char path[MAXPATHLEN];
        int expisroot;

        if (unxa->nxa_flags == NXA_CHECK) {
                /* just check if the path is an NFS-exportable file system */
                error = copyinstr(unxa->nxa_fspath, path, MAXPATHLEN, &pathlen);
                if (error)
                        return (error);
                NDINIT(&mnd, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
                        UIO_SYSSPACE, CAST_USER_ADDR_T(path), ctx);
                error = namei(&mnd);
                if (error)
                        return (error);
                mvp = mnd.ni_vp;
                mp = vnode_mount(mvp);
                /* make sure it's the root of a file system */
                if (!vnode_isvroot(mvp))
                        error = EINVAL;
                /* make sure the file system is NFS-exportable */
                if (!error) {
                        nfh.nfh_len = NFSV3_MAX_FID_SIZE;
                        error = VFS_VPTOFH(mvp, (int*)&nfh.nfh_len, &nfh.nfh_fid[0], NULL);
                }
                if (!error && (nfh.nfh_len > (int)NFSV3_MAX_FID_SIZE))
                        error = EIO;
                if (!error && !(mp->mnt_vtable->vfc_vfsflags & VFC_VFSREADDIR_EXTENDED))
                        error = EISDIR;
                vnode_put(mvp);
                nameidone(&mnd);
                return (error);
        }

        /* all other operations: must be super user */
        if ((error = vfs_context_suser(ctx)))
                return (error);

        if (unxa->nxa_flags & NXA_DELETE_ALL) {
                /* delete all exports on all file systems */
                lck_rw_lock_exclusive(&nfsrv_export_rwlock);
                while ((nxfs = LIST_FIRST(&nfsrv_exports))) {
                        mp = vfs_getvfs_by_mntonname(nxfs->nxfs_path);
                        if (mp) {
                                vfs_clearflags(mp, MNT_EXPORTED);
                                mount_iterdrop(mp);
                                mp = NULL;
                        }
                        /* delete all exports on this file system */
                        while ((nx = LIST_FIRST(&nxfs->nxfs_exports))) {
                                LIST_REMOVE(nx, nx_next);
                                LIST_REMOVE(nx, nx_hash);
                                /* delete all netopts for this export */
                                nfsrv_free_addrlist(nx, NULL);
                                nx->nx_flags &= ~NX_DEFAULTEXPORT;
                                if (IS_VALID_CRED(nx->nx_defopt.nxo_cred)) {
                                        kauth_cred_unref(&nx->nx_defopt.nxo_cred);
                                }
                                /* free active user list for this export */
                                nfsrv_free_user_list(&nx->nx_user_list);
                                FREE(nx->nx_path, M_TEMP);
                                FREE(nx, M_TEMP);
                        }
                        LIST_REMOVE(nxfs, nxfs_next);
                        FREE(nxfs->nxfs_path, M_TEMP);
                        FREE(nxfs, M_TEMP);
                }
                if (nfsrv_export_hashtbl) {
                        /* all exports deleted, clean up export hash table */
                        FREE(nfsrv_export_hashtbl, M_TEMP);
                        nfsrv_export_hashtbl = NULL;
                }
                lck_rw_done(&nfsrv_export_rwlock);
                return (0);
        }

        error = copyinstr(unxa->nxa_fspath, path, MAXPATHLEN, &pathlen);
        if (error)
                return (error);

        lck_rw_lock_exclusive(&nfsrv_export_rwlock);

        /* init export hash table if not already */
        if (!nfsrv_export_hashtbl) {
                if (nfsrv_export_hash_size <= 0)
                        nfsrv_export_hash_size = NFSRVEXPHASHSZ;
                nfsrv_export_hashtbl = hashinit(nfsrv_export_hash_size, M_TEMP, &nfsrv_export_hash);
        }

        // first check if we've already got an exportfs with the given ID
        LIST_FOREACH(nxfs, &nfsrv_exports, nxfs_next) {
                if (nxfs->nxfs_id == unxa->nxa_fsid)
                        break;
        }
        if (nxfs) {
                /* verify exported FS path matches given path */
                if (strncmp(path, nxfs->nxfs_path, MAXPATHLEN)) {
                        error = EEXIST;
                        goto unlock_out;
                }
                if ((unxa->nxa_flags & (NXA_ADD|NXA_OFFLINE)) == NXA_ADD) {
                        /* if adding, verify that the mount is still what we expect */
                        mp = vfs_getvfs_by_mntonname(nxfs->nxfs_path);
                        if (mp) {
                                mount_ref(mp, 0);
                                mount_iterdrop(mp);
                        }
                        /* find exported FS root vnode */
                        NDINIT(&mnd, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
                                UIO_SYSSPACE, CAST_USER_ADDR_T(nxfs->nxfs_path), ctx);
                        error = namei(&mnd);
                        if (error)
                                goto unlock_out;
                        mvp = mnd.ni_vp;
                        /* make sure it's (still) the root of a file system */
                        if (!vnode_isvroot(mvp)) {
                                error = EINVAL;
                                goto out;
                        }
                        /* sanity check: this should be same mount */
                        if (mp != vnode_mount(mvp)) {
                                error = EINVAL;
                                goto out;
                        }
                }
        } else {
                /* no current exported file system with that ID */
                if (!(unxa->nxa_flags & NXA_ADD)) {
                        error = ENOENT;
                        goto unlock_out;
                }

                /* find exported FS root vnode */
                NDINIT(&mnd, LOOKUP, OP_LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
                        UIO_SYSSPACE, CAST_USER_ADDR_T(path), ctx);
                error = namei(&mnd);
                if (error) {
                        if (!(unxa->nxa_flags & NXA_OFFLINE))
                                goto unlock_out;
                } else {
                        mvp = mnd.ni_vp;
                        /* make sure it's the root of a file system */
                        if (!vnode_isvroot(mvp)) {
                                /* bail if not marked offline */
                                if (!(unxa->nxa_flags & NXA_OFFLINE)) {
                                        error = EINVAL;
                                        goto out;
                                }
                                vnode_put(mvp);
                                nameidone(&mnd);
                                mvp = NULL;
                        } else {
                                mp = vnode_mount(mvp);
                                mount_ref(mp, 0);

                                /* make sure the file system is NFS-exportable */
                                nfh.nfh_len = NFSV3_MAX_FID_SIZE;
                                error = VFS_VPTOFH(mvp, (int*)&nfh.nfh_len, &nfh.nfh_fid[0], NULL);
                                if (!error && (nfh.nfh_len > (int)NFSV3_MAX_FID_SIZE))
                                        error = EIO;
                                if (!error && !(mp->mnt_vtable->vfc_vfsflags & VFC_VFSREADDIR_EXTENDED))
                                        error = EISDIR;
                                if (error)
                                        goto out;
                        }
                }

                /* add an exportfs for it */
                MALLOC(nxfs, struct nfs_exportfs *, sizeof(struct nfs_exportfs), M_TEMP, M_WAITOK);
                if (!nxfs) {
                        error = ENOMEM;
                        goto out;
                }
                bzero(nxfs, sizeof(struct nfs_exportfs));
                nxfs->nxfs_id = unxa->nxa_fsid;
                MALLOC(nxfs->nxfs_path, char*, pathlen, M_TEMP, M_WAITOK);
                if (!nxfs->nxfs_path) {
                        FREE(nxfs, M_TEMP);
                        error = ENOMEM;
                        goto out;
                }
                bcopy(path, nxfs->nxfs_path, pathlen);
                /* insert into list in reverse-sorted order */
                nxfs3 = NULL;
                LIST_FOREACH(nxfs2, &nfsrv_exports, nxfs_next) {
                        if (strncmp(nxfs->nxfs_path, nxfs2->nxfs_path, MAXPATHLEN) > 0)
                                break;
                        nxfs3 = nxfs2;
                }
                if (nxfs2)
                        LIST_INSERT_BEFORE(nxfs2, nxfs, nxfs_next);
                else if (nxfs3)
                        LIST_INSERT_AFTER(nxfs3, nxfs, nxfs_next);
                else
                        LIST_INSERT_HEAD(&nfsrv_exports, nxfs, nxfs_next);

                /* make sure any quotas are enabled before we export the file system */
                if (mp)
                        enablequotas(mp, ctx);
        }

        if (unxa->nxa_exppath) {
                error = copyinstr(unxa->nxa_exppath, path, MAXPATHLEN, &pathlen);
                if (error)
                        goto out;
                LIST_FOREACH(nx, &nxfs->nxfs_exports, nx_next) {
                        if (nx->nx_id == unxa->nxa_expid)
                                break;
                }
                if (nx) {
                        /* verify exported FS path matches given path */
                        if (strncmp(path, nx->nx_path, MAXPATHLEN)) {
                                error = EEXIST;
                                goto out;
                        }
                } else {
                        /* no current export with that ID */
                        if (!(unxa->nxa_flags & NXA_ADD)) {
                                error = ENOENT;
                                goto out;
                        }
                        /* add an export for it */
                        MALLOC(nx, struct nfs_export *, sizeof(struct nfs_export), M_TEMP, M_WAITOK);
                        if (!nx) {
                                error = ENOMEM;
                                goto out1;
                        }
                        bzero(nx, sizeof(struct nfs_export));
                        nx->nx_id = unxa->nxa_expid;
                        nx->nx_fs = nxfs;
                        microtime(&nx->nx_exptime);
                        MALLOC(nx->nx_path, char*, pathlen, M_TEMP, M_WAITOK);
                        if (!nx->nx_path) {
                                error = ENOMEM;
                                FREE(nx, M_TEMP);
                                nx = NULL;
                                goto out1;
                        }
                        bcopy(path, nx->nx_path, pathlen);
                        /* initialize the active user list */
                        nfsrv_init_user_list(&nx->nx_user_list);
                        /* insert into list in reverse-sorted order */
                        nx3 = NULL;
                        LIST_FOREACH(nx2, &nxfs->nxfs_exports, nx_next) {
                                if (strncmp(nx->nx_path, nx2->nx_path, MAXPATHLEN) > 0)
                                        break;
                                nx3 = nx2;
                        }
                        if (nx2)
                                LIST_INSERT_BEFORE(nx2, nx, nx_next);
                        else if (nx3)
                                LIST_INSERT_AFTER(nx3, nx, nx_next);
                        else
                                LIST_INSERT_HEAD(&nxfs->nxfs_exports, nx, nx_next);
                        /* insert into hash */
                        LIST_INSERT_HEAD(NFSRVEXPHASH(nxfs->nxfs_id, nx->nx_id), nx, nx_hash);

                        /*
                         * We don't allow/support nested exports.  Check if the new entry
                         * nests with the entries before and after or if there's an
                         * entry for the file system root and subdirs.
                         */
                        error = 0;
                        if ((nx3 && !strncmp(nx3->nx_path, nx->nx_path, pathlen - 1) &&
                                    (nx3->nx_path[pathlen-1] == '/')) ||
                            (nx2 && !strncmp(nx2->nx_path, nx->nx_path, strlen(nx2->nx_path)) &&
                                    (nx->nx_path[strlen(nx2->nx_path)] == '/')))
                                error = EINVAL;
                        if (!error) {
                                /* check export conflict with fs root export and vice versa */
                                expisroot = !nx->nx_path[0] ||
                                            ((nx->nx_path[0] == '.') && !nx->nx_path[1]);
                                LIST_FOREACH(nx2, &nxfs->nxfs_exports, nx_next) {
                                        if (expisroot) {
                                                if (nx2 != nx)
                                                        break;
                                        } else if (!nx2->nx_path[0])
                                                break;
                                        else if ((nx2->nx_path[0] == '.') && !nx2->nx_path[1])
                                                break;
                                }
                                if (nx2)
                                        error = EINVAL;
                        }
                        if (error) {
                                /*
                                 * Don't actually return an error because mountd is
                                 * probably about to delete the conflicting export.
                                 * This can happen when a new export momentarily conflicts
                                 * with an old export while the transition is being made.
                                 * Theoretically, mountd could be written to avoid this
                                 * transient situation - but it would greatly increase the
                                 * complexity of mountd for very little overall benefit.
                                 */
                                printf("nfsrv_export: warning: nested exports: %s/%s\n",
                                        nxfs->nxfs_path, nx->nx_path);
                                error = 0;
                        }
                        nx->nx_fh.nfh_xh.nxh_flags = NXHF_INVALIDFH;
                }
                /* make sure file handle is set up */
                if ((nx->nx_fh.nfh_xh.nxh_version != htonl(NFS_FH_VERSION)) ||
                    (nx->nx_fh.nfh_xh.nxh_flags & NXHF_INVALIDFH)) {
                        /* try to set up export root file handle */
                        nx->nx_fh.nfh_xh.nxh_version = htonl(NFS_FH_VERSION);
                        nx->nx_fh.nfh_xh.nxh_fsid = htonl(nx->nx_fs->nxfs_id);
                        nx->nx_fh.nfh_xh.nxh_expid = htonl(nx->nx_id);
                        nx->nx_fh.nfh_xh.nxh_flags = 0;
                        nx->nx_fh.nfh_xh.nxh_reserved = 0;
                        nx->nx_fh.nfh_fhp = (u_char*)&nx->nx_fh.nfh_xh;
                        bzero(&nx->nx_fh.nfh_fid[0], NFSV2_MAX_FID_SIZE);
                        if (mvp) {
                                /* find export root vnode */
                                if (!nx->nx_path[0] || ((nx->nx_path[0] == '.') && !nx->nx_path[1])) {
                                        /* exporting file system's root directory */
                                        xvp = mvp;
                                        vnode_get(xvp);
                                } else {
                                        xnd.ni_cnd.cn_nameiop = LOOKUP;
#if CONFIG_TRIGGERS
                                        xnd.ni_op = OP_LOOKUP;
#endif
                                        xnd.ni_cnd.cn_flags = LOCKLEAF;
                                        xnd.ni_pathlen = pathlen - 1;
                                        xnd.ni_cnd.cn_nameptr = xnd.ni_cnd.cn_pnbuf = path;
                                        xnd.ni_startdir = mvp;
                                        xnd.ni_usedvp   = mvp;
                                        xnd.ni_cnd.cn_context = ctx;
                                        while ((error = lookup(&xnd)) == ERECYCLE) {
                                                xnd.ni_cnd.cn_flags = LOCKLEAF;
                                                xnd.ni_cnd.cn_nameptr = xnd.ni_cnd.cn_pnbuf;
                                                xnd.ni_usedvp = xnd.ni_dvp = xnd.ni_startdir = mvp;
                                        }
                                        if (error)
                                                goto out1;
                                        xvp = xnd.ni_vp;
                                }

                                if (vnode_vtype(xvp) != VDIR) {
                                        error = EINVAL;
                                        vnode_put(xvp);
                                        goto out1;
                                }

                                /* grab file handle */
                                nx->nx_fh.nfh_len = NFSV3_MAX_FID_SIZE;
                                error = VFS_VPTOFH(xvp, (int*)&nx->nx_fh.nfh_len, &nx->nx_fh.nfh_fid[0], NULL);
                                if (!error && (nx->nx_fh.nfh_len > (int)NFSV3_MAX_FID_SIZE)) {
                                        error = EIO;
                                } else {
                                        nx->nx_fh.nfh_xh.nxh_fidlen = nx->nx_fh.nfh_len;
                                        nx->nx_fh.nfh_len += sizeof(nx->nx_fh.nfh_xh);
                                }

                                vnode_put(xvp);
                                if (error)
                                        goto out1;
                        } else {
                                nx->nx_fh.nfh_xh.nxh_flags = NXHF_INVALIDFH;
                                nx->nx_fh.nfh_xh.nxh_fidlen = 0;
                                nx->nx_fh.nfh_len = sizeof(nx->nx_fh.nfh_xh);
                        }
                }
        } else {
                nx = NULL;
        }

        /* perform the export changes */
        if (unxa->nxa_flags & NXA_DELETE) {
                if (!nx) {
                        /* delete all exports on this file system */
                        while ((nx = LIST_FIRST(&nxfs->nxfs_exports))) {
                                LIST_REMOVE(nx, nx_next);
                                LIST_REMOVE(nx, nx_hash);
                                /* delete all netopts for this export */
                                nfsrv_free_addrlist(nx, NULL);
                                nx->nx_flags &= ~NX_DEFAULTEXPORT;
                                if (IS_VALID_CRED(nx->nx_defopt.nxo_cred)) {
                                        kauth_cred_unref(&nx->nx_defopt.nxo_cred);
                                }
                                /* delete active user list for this export */
                                nfsrv_free_user_list(&nx->nx_user_list);
                                FREE(nx->nx_path, M_TEMP);
                                FREE(nx, M_TEMP);
                        }
                        goto out1;
                } else if (!unxa->nxa_netcount) {
                        /* delete all netopts for this export */
                        nfsrv_free_addrlist(nx, NULL);
                        nx->nx_flags &= ~NX_DEFAULTEXPORT;
                        if (IS_VALID_CRED(nx->nx_defopt.nxo_cred)) {
                                kauth_cred_unref(&nx->nx_defopt.nxo_cred);
                        }
                } else {
                        /* delete only the netopts for the given addresses */
                        error = nfsrv_free_addrlist(nx, unxa);
                        if (error)
                                goto out1;
                }
        }
        if (unxa->nxa_flags & NXA_ADD) {
                /* 
                 * If going offline set the export time so that when
                 * coming back on line we will present a new write verifier
                 * to the client.
                 */
                if (unxa->nxa_flags & NXA_OFFLINE)
                        microtime(&nx->nx_exptime);

                error = nfsrv_hang_addrlist(nx, unxa);
                if (!error && mp)
                        vfs_setflags(mp, MNT_EXPORTED);
        }

out1:
        if (nx && !nx->nx_expcnt) {
                /* export has no export options */
                LIST_REMOVE(nx, nx_next);
                LIST_REMOVE(nx, nx_hash);
                /* delete active user list for this export */
                nfsrv_free_user_list(&nx->nx_user_list);
                FREE(nx->nx_path, M_TEMP);
                FREE(nx, M_TEMP);
        }
        if (LIST_EMPTY(&nxfs->nxfs_exports)) {
                /* exported file system has no more exports */
                LIST_REMOVE(nxfs, nxfs_next);
                FREE(nxfs->nxfs_path, M_TEMP);
                FREE(nxfs, M_TEMP);
                if (mp)
                        vfs_clearflags(mp, MNT_EXPORTED);
        }

out:
        if (mvp) {
                vnode_put(mvp);
                nameidone(&mnd);
        }
unlock_out:
        if (mp)
                mount_drop(mp, 0);
        lck_rw_done(&nfsrv_export_rwlock);
        return (error);
}

/*
 * Check if there is a least one export that will allow this address.
 *
 * Return 0, if there is an export that will allow this address,
 * else return EACCES
 */
int
nfsrv_check_exports_allow_address(mbuf_t nam)
{
        struct nfs_exportfs             *nxfs;
        struct nfs_export               *nx;
        struct nfs_export_options       *nxo;

        if (nam == NULL)
                return (EACCES);

        lck_rw_lock_shared(&nfsrv_export_rwlock);
        LIST_FOREACH(nxfs, &nfsrv_exports, nxfs_next) {
                LIST_FOREACH(nx, &nxfs->nxfs_exports, nx_next) {
                        /* A little optimizing by checking for the default first */
                        if (nx->nx_flags & NX_DEFAULTEXPORT)
                                nxo = &nx->nx_defopt;
                        if (nxo || (nxo = nfsrv_export_lookup(nx, nam)))
                                goto found;
                }
        }
found:
        lck_rw_done(&nfsrv_export_rwlock);

        return (nxo ? 0 : EACCES);
}

struct nfs_export_options *
nfsrv_export_lookup(struct nfs_export *nx, mbuf_t nam)
{
        struct nfs_export_options *nxo = NULL;
        struct nfs_netopt *no = NULL;
        struct radix_node_head *rnh;
        struct sockaddr *saddr;

        /* Lookup in the export list first. */
        if (nam != NULL) {
                saddr = mbuf_data(nam);
                rnh = nx->nx_rtable[saddr->sa_family];
                if (rnh != NULL) {
                        no = (struct nfs_netopt *)
                                (*rnh->rnh_matchaddr)((caddr_t)saddr, rnh);
                        if (no && no->no_rnodes->rn_flags & RNF_ROOT)
                                no = NULL;
                        if (no)
                                nxo = &no->no_opt;
                }
        }
        /* If no address match, use the default if it exists. */
        if ((nxo == NULL) && (nx->nx_flags & NX_DEFAULTEXPORT))
                nxo = &nx->nx_defopt;
        return (nxo);
}

/* find an export for the given handle */
struct nfs_export *
nfsrv_fhtoexport(struct nfs_filehandle *nfhp)
{
        struct nfs_exphandle *nxh = (struct nfs_exphandle*)nfhp->nfh_fhp;
        struct nfs_export *nx;
        uint32_t fsid, expid;

        if (!nfsrv_export_hashtbl)
                return (NULL);
        fsid = ntohl(nxh->nxh_fsid);
        expid = ntohl(nxh->nxh_expid);
        nx = NFSRVEXPHASH(fsid, expid)->lh_first;
        for (; nx; nx = LIST_NEXT(nx, nx_hash)) {
                if (nx->nx_fs->nxfs_id != fsid)
                        continue;
                if (nx->nx_id != expid)
                        continue;
                break;
        }
        return (nx);
}

/*
 * nfsrv_fhtovp() - convert FH to vnode and export info
 */
int
nfsrv_fhtovp(
        struct nfs_filehandle *nfhp,
        struct nfsrv_descript *nd,
        vnode_t *vpp,
        struct nfs_export **nxp,
        struct nfs_export_options **nxop)
{
        struct nfs_exphandle *nxh = (struct nfs_exphandle*)nfhp->nfh_fhp;
        struct nfs_export_options *nxo;
        u_char *fidp;
        int error;
        struct mount *mp;
        mbuf_t nam = NULL;
        uint32_t v;
        int i, valid;

        *vpp = NULL;
        *nxp = NULL;
        *nxop = NULL;

        if (nd != NULL)
                nam = nd->nd_nam;

        v = ntohl(nxh->nxh_version);
        if (v != NFS_FH_VERSION) {
                /* file handle format not supported */
                return (ESTALE);
        }
        if (nfhp->nfh_len > NFSV3_MAX_FH_SIZE)
                return (EBADRPC);
        if (nfhp->nfh_len < (int)sizeof(struct nfs_exphandle))
                return (ESTALE);
        v = ntohs(nxh->nxh_flags);
        if (v & NXHF_INVALIDFH)
                return (ESTALE);

        *nxp = nfsrv_fhtoexport(nfhp);
        if (!*nxp)
                return (ESTALE);

        /* Get the export option structure for this <export, client> tuple. */
        *nxop = nxo = nfsrv_export_lookup(*nxp, nam);
        if (nam && (*nxop == NULL))
                return (EACCES);

        if (nd != NULL) {
                /* Validate the security flavor of the request */
                for (i = 0, valid = 0; i < nxo->nxo_sec.count; i++) {
                        if (nd->nd_sec == nxo->nxo_sec.flavors[i]) {
                                valid = 1;
                                break;
                        }
                }
                if (!valid) {
                        /*
                         * RFC 2623 section 2.3.2 recommends no authentication
                         * requirement for certain NFS procedures used for mounting.
                         * This allows an unauthenticated superuser on the client
                         * to do mounts for the benefit of authenticated users.
                         */
                        if (nd->nd_vers == NFS_VER2)
                                if (nd->nd_procnum == NFSV2PROC_GETATTR ||
                                    nd->nd_procnum == NFSV2PROC_STATFS)
                                        valid = 1;
                        if (nd->nd_vers == NFS_VER3)
                                if (nd->nd_procnum == NFSPROC_FSINFO)
                                        valid = 1;

                        if (!valid)
                                return (NFSERR_AUTHERR | AUTH_REJECTCRED);
                }
        }

        if (nxo && (nxo->nxo_flags & NX_OFFLINE))
                return ((nd == NULL || nd->nd_vers == NFS_VER2) ? ESTALE : NFSERR_TRYLATER);

        /* find mount structure */
        mp = vfs_getvfs_by_mntonname((*nxp)->nx_fs->nxfs_path);
        if (mp) {
                error = vfs_busy(mp, LK_NOWAIT);
                mount_iterdrop(mp);
                if (error)
                        mp = NULL;
        }
        if (!mp) {
                /*
                 * We have an export, but no mount?
                 * Perhaps the export just hasn't been marked offline yet.
                 */
                return ((nd == NULL || nd->nd_vers == NFS_VER2) ? ESTALE : NFSERR_TRYLATER);
        }

        fidp = nfhp->nfh_fhp + sizeof(*nxh);
        error = VFS_FHTOVP(mp, nxh->nxh_fidlen, fidp, vpp, NULL);
        vfs_unbusy(mp);
        if (error)
                return (error);
        /* vnode pointer should be good at this point or ... */
        if (*vpp == NULL)
                return (ESTALE);
        return (0);
}

/*
 * nfsrv_credcheck() - check/map credentials according
 * to given export options.
 */
int
nfsrv_credcheck(
        struct nfsrv_descript *nd,
        vfs_context_t ctx,
        __unused struct nfs_export *nx,
        struct nfs_export_options *nxo)
{
        if (nxo && nxo->nxo_cred) {
                if ((nxo->nxo_flags & NX_MAPALL) ||
                    ((nxo->nxo_flags & NX_MAPROOT) && !suser(nd->nd_cr, NULL))) {
                        kauth_cred_ref(nxo->nxo_cred);
                        kauth_cred_unref(&nd->nd_cr);
                        nd->nd_cr = nxo->nxo_cred;
                }
        }
        ctx->vc_ucred = nd->nd_cr;
        return (0);
}

/*
 * nfsrv_vptofh() - convert vnode to file handle for given export
 *
 * If the caller is passing in a vnode for a ".." directory entry,
 * they can pass a directory NFS file handle (dnfhp) which will be
 * checked against the root export file handle.  If it matches, we
 * refuse to provide the file handle for the out-of-export directory.
 */
int
nfsrv_vptofh(
        struct nfs_export *nx,
        int nfsvers,
        struct nfs_filehandle *dnfhp,
        vnode_t vp,
        vfs_context_t ctx,
        struct nfs_filehandle *nfhp)
{
        int error;
        uint32_t maxfidsize;

        nfhp->nfh_fhp = (u_char*)&nfhp->nfh_xh;
        nfhp->nfh_xh.nxh_version = htonl(NFS_FH_VERSION);
        nfhp->nfh_xh.nxh_fsid = htonl(nx->nx_fs->nxfs_id);
        nfhp->nfh_xh.nxh_expid = htonl(nx->nx_id);
        nfhp->nfh_xh.nxh_flags = 0;
        nfhp->nfh_xh.nxh_reserved = 0;

        if (nfsvers == NFS_VER2)
                bzero(&nfhp->nfh_fid[0], NFSV2_MAX_FID_SIZE);

        /* if directory FH matches export root, return invalid FH */
        if (dnfhp && nfsrv_fhmatch(dnfhp, &nx->nx_fh)) {
                if (nfsvers == NFS_VER2)
                        nfhp->nfh_len = NFSX_V2FH;
                else
                        nfhp->nfh_len = sizeof(nfhp->nfh_xh);
                nfhp->nfh_xh.nxh_fidlen = 0;
                nfhp->nfh_xh.nxh_flags = htons(NXHF_INVALIDFH);
                return (0);
        }

        if (nfsvers == NFS_VER2)
                maxfidsize = NFSV2_MAX_FID_SIZE;
        else
                maxfidsize = NFSV3_MAX_FID_SIZE;
        nfhp->nfh_len = maxfidsize;

        error = VFS_VPTOFH(vp, (int*)&nfhp->nfh_len, &nfhp->nfh_fid[0], ctx);
        if (error)
                return (error);
        if (nfhp->nfh_len > maxfidsize)
                return (EOVERFLOW);
        nfhp->nfh_xh.nxh_fidlen = nfhp->nfh_len;
        nfhp->nfh_len += sizeof(nfhp->nfh_xh);
        if ((nfsvers == NFS_VER2) && (nfhp->nfh_len < NFSX_V2FH))
                nfhp->nfh_len = NFSX_V2FH;

        return (0);
}

/*
 * Compare two file handles to see it they're the same.
 * Note that we don't use nfh_len because that may include
 * padding in an NFSv2 file handle.
 */
int
nfsrv_fhmatch(struct nfs_filehandle *fh1, struct nfs_filehandle *fh2)
{
        struct nfs_exphandle *nxh1, *nxh2;
        int len1, len2;

        nxh1 = (struct nfs_exphandle *)fh1->nfh_fhp;
        nxh2 = (struct nfs_exphandle *)fh2->nfh_fhp;
        len1 = sizeof(fh1->nfh_xh) + nxh1->nxh_fidlen;
        len2 = sizeof(fh2->nfh_xh) + nxh2->nxh_fidlen;
        if (len1 != len2)
                return (0);
        if (bcmp(nxh1, nxh2, len1))
                return (0);
        return (1);
}

/*
 * Functions for dealing with active user lists
 */

/*
 * Search the hash table for a user node with a matching IP address and uid field.
 * If found, the node's tm_last timestamp is updated and the node is returned.
 *
 * If not found, a new node is allocated (or reclaimed via LRU), initialized, and returned.
 * Returns NULL if a new node could not be allcoated.
 *
 * The list's user_mutex lock MUST be held.
 */
struct nfs_user_stat_node *
nfsrv_get_user_stat_node(struct nfs_active_user_list *list, struct sockaddr *saddr, uid_t uid)
{
        struct nfs_user_stat_node               *unode;
        struct timeval                          now;
        struct nfs_user_stat_hashtbl_head       *head;

        /* seach the hash table */
        head = NFS_USER_STAT_HASH(list->user_hashtbl, uid);
        LIST_FOREACH(unode, head, hash_link) {
                if ((uid == unode->uid) && (nfs_sockaddr_cmp(saddr, (struct sockaddr*)&unode->sock) == 0)) {
                        /* found matching node */
                        break;
                }
        }

        if (unode) {
                /* found node in the hash table, now update lru position */
                TAILQ_REMOVE(&list->user_lru, unode, lru_link);
                TAILQ_INSERT_TAIL(&list->user_lru, unode, lru_link);

                /* update time stamp */
                microtime(&now);
                unode->tm_last = (uint32_t)now.tv_sec;
                return unode;
        }

        if (list->node_count < nfsrv_user_stat_max_nodes) {
                /* Allocate a new node */
                MALLOC(unode, struct nfs_user_stat_node *, sizeof(struct nfs_user_stat_node),
                        M_TEMP, M_WAITOK | M_ZERO);

                if (!unode)
                        return NULL;

                /* increment node count */
                OSAddAtomic(1, &nfsrv_user_stat_node_count);
                list->node_count++;
        } else {
                /* reuse the oldest node in the lru list */
                unode = TAILQ_FIRST(&list->user_lru);

                if (!unode)
                        return NULL;

                /* Remove the node */
                TAILQ_REMOVE(&list->user_lru, unode, lru_link);
                LIST_REMOVE(unode, hash_link);
        }

        /* Initialize the node */
        unode->uid = uid;
        bcopy(saddr, &unode->sock, saddr->sa_len);
        microtime(&now);
        unode->ops = 0;
        unode->bytes_read = 0;
        unode->bytes_written = 0;
        unode->tm_start = (uint32_t)now.tv_sec;
        unode->tm_last = (uint32_t)now.tv_sec;

        /* insert the node  */
        TAILQ_INSERT_TAIL(&list->user_lru, unode, lru_link);
        LIST_INSERT_HEAD(head, unode, hash_link);

        return unode;
}

void
nfsrv_update_user_stat(struct nfs_export *nx, struct nfsrv_descript *nd, uid_t uid, u_int ops, u_int rd_bytes, u_int wr_bytes)
{
        struct nfs_user_stat_node       *unode;
        struct nfs_active_user_list     *ulist;
        struct sockaddr                 *saddr;

        if ((!nfsrv_user_stat_enabled) || (!nx) || (!nd) || (!nd->nd_nam))
                return;

        saddr = (struct sockaddr *)mbuf_data(nd->nd_nam);

        /* check address family before going any further */
        if ((saddr->sa_family != AF_INET) && (saddr->sa_family != AF_INET6))
                return;

        ulist = &nx->nx_user_list;

        /* lock the active user list */
        lck_mtx_lock(&ulist->user_mutex);

        /* get the user node */
        unode = nfsrv_get_user_stat_node(ulist, saddr, uid);

        if (!unode) {
                lck_mtx_unlock(&ulist->user_mutex);
                return;
        }

        /* update counters */
        unode->ops += ops;
        unode->bytes_read += rd_bytes;
        unode->bytes_written += wr_bytes;

        /* done */
        lck_mtx_unlock(&ulist->user_mutex);
}

/* initialize an active user list */
void
nfsrv_init_user_list(struct nfs_active_user_list *ulist)
{
        uint i;

        /* initialize the lru */
        TAILQ_INIT(&ulist->user_lru);

        /* initialize the hash table */
        for(i = 0; i < NFS_USER_STAT_HASH_SIZE; i++)
                LIST_INIT(&ulist->user_hashtbl[i]);
        ulist->node_count = 0;

        lck_mtx_init(&ulist->user_mutex, nfsrv_active_user_mutex_group, LCK_ATTR_NULL);
}

/* Free all nodes in an active user list */
void
nfsrv_free_user_list(struct nfs_active_user_list *ulist)
{
        struct nfs_user_stat_node *unode;

        if (!ulist)
                return;

        while ((unode = TAILQ_FIRST(&ulist->user_lru))) {
                /* Remove node and free */
                TAILQ_REMOVE(&ulist->user_lru, unode, lru_link);
                LIST_REMOVE(unode, hash_link);
                FREE(unode, M_TEMP);

                /* decrement node count */
                OSAddAtomic(-1, &nfsrv_user_stat_node_count);
        }
        ulist->node_count = 0;

        lck_mtx_destroy(&ulist->user_mutex, nfsrv_active_user_mutex_group);
}

/* Reclaim old expired user nodes from active user lists. */
void
nfsrv_active_user_list_reclaim(void)
{
        struct nfs_exportfs                     *nxfs;
        struct nfs_export                       *nx;
        struct nfs_active_user_list             *ulist;
        struct nfs_user_stat_hashtbl_head       oldlist;
        struct nfs_user_stat_node               *unode, *unode_next;
        struct timeval                          now;
        uint32_t                                tstale;

        LIST_INIT(&oldlist);

        lck_rw_lock_shared(&nfsrv_export_rwlock);
        microtime(&now);
        tstale = now.tv_sec - nfsrv_user_stat_max_idle_sec;
        LIST_FOREACH(nxfs, &nfsrv_exports, nxfs_next) {
                LIST_FOREACH(nx, &nxfs->nxfs_exports, nx_next) {
                        /* Scan through all user nodes of this export */
                        ulist = &nx->nx_user_list;
                        lck_mtx_lock(&ulist->user_mutex);
                        for (unode = TAILQ_FIRST(&ulist->user_lru); unode; unode = unode_next) {
                                unode_next = TAILQ_NEXT(unode, lru_link);

                                /* check if this node has expired */
                                if (unode->tm_last >= tstale)
                                        break;

                                /* Remove node from the active user list */
                                TAILQ_REMOVE(&ulist->user_lru, unode, lru_link);
                                LIST_REMOVE(unode, hash_link);

                                /* Add node to temp list */
                                LIST_INSERT_HEAD(&oldlist, unode, hash_link);

                                /* decrement node count */
                                OSAddAtomic(-1, &nfsrv_user_stat_node_count);
                                ulist->node_count--;
                        }
                        /* can unlock this export's list now */
                        lck_mtx_unlock(&ulist->user_mutex);
                }
        }
        lck_rw_done(&nfsrv_export_rwlock);

        /* Free expired nodes */
        while ((unode = LIST_FIRST(&oldlist))) {
                LIST_REMOVE(unode, hash_link);
                FREE(unode, M_TEMP);
        }
}

/*
 * Maps errno values to nfs error numbers.
 * Use NFSERR_IO as the catch all for ones not specifically defined in
 * RFC 1094.
 */
static u_char nfsrv_v2errmap[] = {
  NFSERR_PERM,  NFSERR_NOENT,   NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_NXIO,  NFSERR_IO,      NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_IO,      NFSERR_ACCES,   NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_EXIST,   NFSERR_IO,      NFSERR_NODEV,   NFSERR_NOTDIR,
  NFSERR_ISDIR, NFSERR_IO,      NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_FBIG,    NFSERR_NOSPC,   NFSERR_IO,      NFSERR_ROFS,
  NFSERR_IO,    NFSERR_IO,      NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_IO,      NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_IO,      NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_IO,      NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_IO,      NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_IO,      NFSERR_IO,      NFSERR_IO,      NFSERR_IO,
  NFSERR_IO,    NFSERR_IO,      NFSERR_NAMETOL, NFSERR_IO,      NFSERR_IO,
  NFSERR_NOTEMPTY, NFSERR_IO,   NFSERR_IO,      NFSERR_DQUOT,   NFSERR_STALE,
};

/*
 * Maps errno values to nfs error numbers.
 * Although it is not obvious whether or not NFS clients really care if
 * a returned error value is in the specified list for the procedure, the
 * safest thing to do is filter them appropriately. For Version 2, the
 * X/Open XNFS document is the only specification that defines error values
 * for each RPC (The RFC simply lists all possible error values for all RPCs),
 * so I have decided to not do this for Version 2.
 * The first entry is the default error return and the rest are the valid
 * errors for that RPC in increasing numeric order.
 */
static short nfsv3err_null[] = {
        0,
        0,
};

static short nfsv3err_getattr[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_setattr[] = {
        NFSERR_IO,
        NFSERR_PERM,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_INVAL,
        NFSERR_NOSPC,
        NFSERR_ROFS,
        NFSERR_DQUOT,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOT_SYNC,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_lookup[] = {
        NFSERR_IO,
        NFSERR_NOENT,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_NOTDIR,
        NFSERR_NAMETOL,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_access[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_readlink[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_INVAL,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOTSUPP,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_read[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_NXIO,
        NFSERR_ACCES,
        NFSERR_INVAL,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_write[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_INVAL,
        NFSERR_FBIG,
        NFSERR_NOSPC,
        NFSERR_ROFS,
        NFSERR_DQUOT,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_create[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_EXIST,
        NFSERR_NOTDIR,
        NFSERR_NOSPC,
        NFSERR_ROFS,
        NFSERR_NAMETOL,
        NFSERR_DQUOT,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOTSUPP,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_mkdir[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_EXIST,
        NFSERR_NOTDIR,
        NFSERR_NOSPC,
        NFSERR_ROFS,
        NFSERR_NAMETOL,
        NFSERR_DQUOT,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOTSUPP,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_symlink[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_EXIST,
        NFSERR_NOTDIR,
        NFSERR_NOSPC,
        NFSERR_ROFS,
        NFSERR_NAMETOL,
        NFSERR_DQUOT,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOTSUPP,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_mknod[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_EXIST,
        NFSERR_NOTDIR,
        NFSERR_NOSPC,
        NFSERR_ROFS,
        NFSERR_NAMETOL,
        NFSERR_DQUOT,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOTSUPP,
        NFSERR_SERVERFAULT,
        NFSERR_BADTYPE,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_remove[] = {
        NFSERR_IO,
        NFSERR_NOENT,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_NOTDIR,
        NFSERR_ROFS,
        NFSERR_NAMETOL,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_rmdir[] = {
        NFSERR_IO,
        NFSERR_NOENT,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_EXIST,
        NFSERR_NOTDIR,
        NFSERR_INVAL,
        NFSERR_ROFS,
        NFSERR_NAMETOL,
        NFSERR_NOTEMPTY,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOTSUPP,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_rename[] = {
        NFSERR_IO,
        NFSERR_NOENT,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_EXIST,
        NFSERR_XDEV,
        NFSERR_NOTDIR,
        NFSERR_ISDIR,
        NFSERR_INVAL,
        NFSERR_NOSPC,
        NFSERR_ROFS,
        NFSERR_MLINK,
        NFSERR_NAMETOL,
        NFSERR_NOTEMPTY,
        NFSERR_DQUOT,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOTSUPP,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_link[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_EXIST,
        NFSERR_XDEV,
        NFSERR_NOTDIR,
        NFSERR_INVAL,
        NFSERR_NOSPC,
        NFSERR_ROFS,
        NFSERR_MLINK,
        NFSERR_NAMETOL,
        NFSERR_DQUOT,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_NOTSUPP,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_readdir[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_NOTDIR,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_BAD_COOKIE,
        NFSERR_TOOSMALL,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_readdirplus[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_ACCES,
        NFSERR_NOTDIR,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_BAD_COOKIE,
        NFSERR_NOTSUPP,
        NFSERR_TOOSMALL,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_fsstat[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_fsinfo[] = {
        NFSERR_STALE,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_pathconf[] = {
        NFSERR_STALE,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short nfsv3err_commit[] = {
        NFSERR_IO,
        NFSERR_IO,
        NFSERR_STALE,
        NFSERR_BADHANDLE,
        NFSERR_SERVERFAULT,
        NFSERR_TRYLATER,
        0,
};

static short *nfsrv_v3errmap[] = {
        nfsv3err_null,
        nfsv3err_getattr,
        nfsv3err_setattr,
        nfsv3err_lookup,
        nfsv3err_access,
        nfsv3err_readlink,
        nfsv3err_read,
        nfsv3err_write,
        nfsv3err_create,
        nfsv3err_mkdir,
        nfsv3err_symlink,
        nfsv3err_mknod,
        nfsv3err_remove,
        nfsv3err_rmdir,
        nfsv3err_rename,
        nfsv3err_link,
        nfsv3err_readdir,
        nfsv3err_readdirplus,
        nfsv3err_fsstat,
        nfsv3err_fsinfo,
        nfsv3err_pathconf,
        nfsv3err_commit,
};

/*
 * Map errnos to NFS error numbers. For Version 3 also filter out error
 * numbers not specified for the associated procedure.
 */
int
nfsrv_errmap(struct nfsrv_descript *nd, int err)
{
        short *defaulterrp, *errp;

        if (nd->nd_vers == NFS_VER2) {
                if (err <= (int)sizeof(nfsrv_v2errmap))
                        return ((int)nfsrv_v2errmap[err - 1]);
                return (NFSERR_IO);
        }
        /* NFSv3 */
        if (nd->nd_procnum > NFSPROC_COMMIT)
                return (err & 0xffff);
        errp = defaulterrp = nfsrv_v3errmap[nd->nd_procnum];
        while (*++errp) {
                if (*errp == err)
                        return (err);
                else if (*errp > err)
                        break;
        }
        return ((int)*defaulterrp);
}

#endif /* NFSSERVER */