/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1989, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rick Macklem at The University of Guelph.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/syslog.h>
#include <sys/wait.h>
#include <sys/mount.h>
#include <sys/fcntl.h>
#include <sys/linker.h>
#include <sys/module.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/ucred.h>

#include <rpc/rpc.h>
#include <rpc/pmap_clnt.h>
#include <rpcsvc/nfs_prot.h>

#include <netdb.h>
#include <arpa/inet.h>
#include <nfs/nfssvc.h>

#include <fs/nfs/nfsproto.h>
#include <fs/nfs/nfskpiport.h>
#include <fs/nfs/nfs.h>

#include <err.h>
#include <errno.h>
#include <libutil.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sysexits.h>

#include <getopt.h>

static int      debug = 0;
static int      nofork = 0;

#define DEFAULT_PIDFILE         "/var/run/nfsd.pid"
#define NFSD_STABLERESTART      "/var/db/nfs-stablerestart"
#define NFSD_STABLEBACKUP       "/var/db/nfs-stablerestart.bak"
#define MAXNFSDCNT      256
#define DEFNFSDCNT       4
#define NFS_VER2         2
#define NFS_VER3         3
#define NFS_VER4         4
static pid_t children[MAXNFSDCNT]; /* PIDs of children */
static pid_t masterpid;            /* PID of master/parent */
static struct pidfh *masterpidfh = NULL;        /* pidfh of master/parent */
static int nfsdcnt;             /* number of children */
static int nfsdcnt_set;
static int minthreads;
static int maxthreads;
static int nfssvc_nfsd;         /* Set to correct NFSSVC_xxx flag */
static int stablefd = -1;       /* Fd for the stable restart file */
static int backupfd;            /* Fd for the backup stable restart file */
static const char *getopt_shortopts;
static const char *getopt_usage;
static int nfs_minvers = NFS_VER2;

static int minthreads_set;
static int maxthreads_set;

static struct option longopts[] = {
        { "debug", no_argument, &debug, 1 },
        { "minthreads", required_argument, &minthreads_set, 1 },
        { "maxthreads", required_argument, &maxthreads_set, 1 },
        { "pnfs", required_argument, NULL, 'p' },
        { "mirror", required_argument, NULL, 'm' },
        { NULL, 0, NULL, 0}
};

static void     cleanup(int);
static void     child_cleanup(int);
static void     killchildren(void);
static void     nfsd_exit(int);
static void     nonfs(int);
static void     reapchild(int);
static int      setbindhost(struct addrinfo **ia, const char *bindhost,
                    struct addrinfo hints);
static void     start_server(int, struct nfsd_nfsd_args *, const char *vhost);
static void     unregistration(void);
static void     usage(void);
static void     open_stable(int *, int *);
static void     copy_stable(int, int);
static void     backup_stable(int);
static void     set_nfsdcnt(int);
static void     parse_dsserver(const char *, struct nfsd_nfsd_args *);

/*
 * Nfs server daemon mostly just a user context for nfssvc()
 *
 * 1 - do file descriptor and signal cleanup
 * 2 - fork the nfsd(s)
 * 3 - create server socket(s)
 * 4 - register socket with rpcbind
 *
 * For connectionless protocols, just pass the socket into the kernel via.
 * nfssvc().
 * For connection based sockets, loop doing accepts. When you get a new
 * socket from accept, pass the msgsock into the kernel via. nfssvc().
 * The arguments are:
 *      -r - reregister with rpcbind
 *      -d - unregister with rpcbind
 *      -t - support tcp nfs clients
 *      -u - support udp nfs clients
 *      -e - forces it to run a server that supports nfsv4
 *      -p - enable a pNFS service
 *      -m - set the mirroring level for a pNFS service
 * followed by "n" which is the number of nfsds' to fork off
 */
int
main(int argc, char **argv)
{
        struct nfsd_addsock_args addsockargs;
        struct addrinfo *ai_udp, *ai_tcp, *ai_udp6, *ai_tcp6, hints;
        struct netconfig *nconf_udp, *nconf_tcp, *nconf_udp6, *nconf_tcp6;
        struct netbuf nb_udp, nb_tcp, nb_udp6, nb_tcp6;
        struct sockaddr_storage peer;
        fd_set ready, sockbits;
        int ch, connect_type_cnt, i, maxsock, msgsock;
        socklen_t len;
        int on = 1, unregister, reregister, sock;
        int tcp6sock, ip6flag, tcpflag, tcpsock;
        int udpflag, ecode, error, s;
        int bindhostc, bindanyflag, rpcbreg, rpcbregcnt;
        int nfssvc_addsock;
        int jailed, longindex = 0;
        size_t jailed_size, nfs_minvers_size;
        const char *lopt;
        char **bindhost = NULL;
        const char *pidfile_path = DEFAULT_PIDFILE;
        pid_t pid, otherpid;
        struct nfsd_nfsd_args nfsdargs;
        const char *vhostname = NULL;

        nfsdargs.mirrorcnt = 1;
        nfsdargs.addr = NULL;
        nfsdargs.addrlen = 0;
        nfsdcnt = DEFNFSDCNT;
        unregister = reregister = tcpflag = maxsock = 0;
        bindanyflag = udpflag = connect_type_cnt = bindhostc = 0;
        getopt_shortopts = "ah:n:rdtuep:m:V:NP:";
        getopt_usage =
            "usage:\n"
            "  nfsd [-ardtueN] [-h bindip]\n"
            "       [-n numservers] [--minthreads #] [--maxthreads #]\n"
            "       [-p/--pnfs dsserver0:/dsserver0-mounted-on-dir,...,"
            "dsserverN:/dsserverN-mounted-on-dir] [-m mirrorlevel]\n"
            "       [-P pidfile ] [-V virtual_hostname]\n";
        while ((ch = getopt_long(argc, argv, getopt_shortopts, longopts,
                    &longindex)) != -1)
                switch (ch) {
                case 'V':
                        if (strlen(optarg) <= MAXHOSTNAMELEN)
                                vhostname = optarg;
                        else
                                warnx("Virtual host name (%s) is too long",
                                    optarg);
                        break;
                case 'a':
                        bindanyflag = 1;
                        break;
                case 'n':
                        set_nfsdcnt(atoi(optarg));
                        break;
                case 'h':
                        bindhostc++;
                        bindhost = realloc(bindhost,sizeof(char *)*bindhostc);
                        if (bindhost == NULL) 
                                errx(1, "Out of memory");
                        bindhost[bindhostc-1] = strdup(optarg);
                        if (bindhost[bindhostc-1] == NULL)
                                errx(1, "Out of memory");
                        break;
                case 'r':
                        reregister = 1;
                        break;
                case 'd':
                        unregister = 1;
                        break;
                case 't':
                        tcpflag = 1;
                        break;
                case 'u':
                        udpflag = 1;
                        break;
                case 'e':
                        /* now a no-op, since this is the default */
                        break;
                case 'p':
                        /* Parse out the DS server host names and mount pts. */
                        parse_dsserver(optarg, &nfsdargs);
                        break;
                case 'm':
                        /* Set the mirror level for a pNFS service. */
                        i = atoi(optarg);
                        if (i < 2 || i > NFSDEV_MAXMIRRORS)
                                errx(1, "Mirror level out of range 2<-->%d",
                                    NFSDEV_MAXMIRRORS);
                        nfsdargs.mirrorcnt = i;
                        break;
                case 'N':
                        nofork = 1;
                        break;
                case 'P':
                        pidfile_path = optarg;
                        break;
                case 0:
                        lopt = longopts[longindex].name;
                        if (!strcmp(lopt, "minthreads")) {
                                minthreads = atoi(optarg);
                        } else if (!strcmp(lopt, "maxthreads")) {
                                maxthreads = atoi(optarg);
                        }
                        break;
                default:
                case '?':
                        usage();
                }
        if (!tcpflag && !udpflag)
                udpflag = 1;
        argv += optind;
        argc -= optind;
        if (minthreads_set && maxthreads_set && minthreads > maxthreads)
                errx(EX_USAGE,
                    "error: minthreads(%d) can't be greater than "
                    "maxthreads(%d)", minthreads, maxthreads);

        /*
         * XXX
         * Backward compatibility, trailing number is the count of daemons.
         */
        if (argc > 1)
                usage();
        if (argc == 1)
                set_nfsdcnt(atoi(argv[0]));

        /*
         * Unless the "-o" option was specified, try and run "nfsd".
         * If "-o" was specified, try and run "nfsserver".
         */
        if (modfind("nfsd") < 0) {
                /* Not present in kernel, try loading it */
                if (kldload("nfsd") < 0 || modfind("nfsd") < 0)
                        errx(1, "NFS server is not available");
        }

        ip6flag = 1;
        s = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
        if (s == -1) {
                if (errno != EPROTONOSUPPORT && errno != EAFNOSUPPORT)
                        err(1, "socket");
                ip6flag = 0;
        } else if (getnetconfigent("udp6") == NULL ||
                getnetconfigent("tcp6") == NULL) {
                ip6flag = 0;
        }
        if (s != -1)
                close(s);

        if (bindhostc == 0 || bindanyflag) {
                bindhostc++;
                bindhost = realloc(bindhost,sizeof(char *)*bindhostc);
                if (bindhost == NULL) 
                        errx(1, "Out of memory");
                bindhost[bindhostc-1] = strdup("*");
                if (bindhost[bindhostc-1] == NULL) 
                        errx(1, "Out of memory");
        }

        if (unregister) {
                /*
                 * Unregister before setting nfs_minvers, in case the
                 * value of vfs.nfsd.server_min_nfsvers has changed
                 * since registering with rpcbind.
                 */
                unregistration();
                exit (0);
        }

        nfs_minvers_size = sizeof(nfs_minvers);
        error = sysctlbyname("vfs.nfsd.server_min_nfsvers", &nfs_minvers,
            &nfs_minvers_size, NULL, 0);
        if (error != 0 || nfs_minvers < NFS_VER2 || nfs_minvers > NFS_VER4) {
                warnx("sysctlbyname(vfs.nfsd.server_min_nfsvers) failed,"
                    " defaulting to NFSv2");
                nfs_minvers = NFS_VER2;
        }

        if (reregister) {
                if (udpflag) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET;
                        hints.ai_socktype = SOCK_DGRAM;
                        hints.ai_protocol = IPPROTO_UDP;
                        ecode = getaddrinfo(NULL, "nfs", &hints, &ai_udp);
                        if (ecode != 0)
                                err(1, "getaddrinfo udp: %s", gai_strerror(ecode));
                        nconf_udp = getnetconfigent("udp");
                        if (nconf_udp == NULL)
                                err(1, "getnetconfigent udp failed");
                        nb_udp.buf = ai_udp->ai_addr;
                        nb_udp.len = nb_udp.maxlen = ai_udp->ai_addrlen;
                        if (nfs_minvers == NFS_VER2)
                                if (!rpcb_set(NFS_PROGRAM, 2, nconf_udp,
                                    &nb_udp))
                                        err(1, "rpcb_set udp failed");
                        if (nfs_minvers <= NFS_VER3)
                                if (!rpcb_set(NFS_PROGRAM, 3, nconf_udp,
                                    &nb_udp))
                                        err(1, "rpcb_set udp failed");
                        freeaddrinfo(ai_udp);
                }
                if (udpflag && ip6flag) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET6;
                        hints.ai_socktype = SOCK_DGRAM;
                        hints.ai_protocol = IPPROTO_UDP;
                        ecode = getaddrinfo(NULL, "nfs", &hints, &ai_udp6);
                        if (ecode != 0)
                                err(1, "getaddrinfo udp6: %s", gai_strerror(ecode));
                        nconf_udp6 = getnetconfigent("udp6");
                        if (nconf_udp6 == NULL)
                                err(1, "getnetconfigent udp6 failed");
                        nb_udp6.buf = ai_udp6->ai_addr;
                        nb_udp6.len = nb_udp6.maxlen = ai_udp6->ai_addrlen;
                        if (nfs_minvers == NFS_VER2)
                                if (!rpcb_set(NFS_PROGRAM, 2, nconf_udp6,
                                    &nb_udp6))
                                        err(1, "rpcb_set udp6 failed");
                        if (nfs_minvers <= NFS_VER3)
                                if (!rpcb_set(NFS_PROGRAM, 3, nconf_udp6,
                                    &nb_udp6))
                                        err(1, "rpcb_set udp6 failed");
                        freeaddrinfo(ai_udp6);
                }
                if (tcpflag) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET;
                        hints.ai_socktype = SOCK_STREAM;
                        hints.ai_protocol = IPPROTO_TCP;
                        ecode = getaddrinfo(NULL, "nfs", &hints, &ai_tcp);
                        if (ecode != 0)
                                err(1, "getaddrinfo tcp: %s", gai_strerror(ecode));
                        nconf_tcp = getnetconfigent("tcp");
                        if (nconf_tcp == NULL)
                                err(1, "getnetconfigent tcp failed");
                        nb_tcp.buf = ai_tcp->ai_addr;
                        nb_tcp.len = nb_tcp.maxlen = ai_tcp->ai_addrlen;
                        if (nfs_minvers == NFS_VER2)
                                if (!rpcb_set(NFS_PROGRAM, 2, nconf_tcp,
                                    &nb_tcp))
                                        err(1, "rpcb_set tcp failed");
                        if (nfs_minvers <= NFS_VER3)
                                if (!rpcb_set(NFS_PROGRAM, 3, nconf_tcp,
                                    &nb_tcp))
                                        err(1, "rpcb_set tcp failed");
                        freeaddrinfo(ai_tcp);
                }
                if (tcpflag && ip6flag) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET6;
                        hints.ai_socktype = SOCK_STREAM;
                        hints.ai_protocol = IPPROTO_TCP;
                        ecode = getaddrinfo(NULL, "nfs", &hints, &ai_tcp6);
                        if (ecode != 0)
                                err(1, "getaddrinfo tcp6: %s", gai_strerror(ecode));
                        nconf_tcp6 = getnetconfigent("tcp6");
                        if (nconf_tcp6 == NULL)
                                err(1, "getnetconfigent tcp6 failed");
                        nb_tcp6.buf = ai_tcp6->ai_addr;
                        nb_tcp6.len = nb_tcp6.maxlen = ai_tcp6->ai_addrlen;
                        if (nfs_minvers == NFS_VER2)
                                if (!rpcb_set(NFS_PROGRAM, 2, nconf_tcp6,
                                    &nb_tcp6))
                                        err(1, "rpcb_set tcp6 failed");
                        if (nfs_minvers <= NFS_VER3)
                                if (!rpcb_set(NFS_PROGRAM, 3, nconf_tcp6, 
                                   &nb_tcp6))
                                        err(1, "rpcb_set tcp6 failed");
                        freeaddrinfo(ai_tcp6);
                }
                exit (0);
        }

        if (pidfile_path != NULL) {
                masterpidfh = pidfile_open(pidfile_path, 0600, &otherpid);
                if (masterpidfh == NULL) {
                        if (errno == EEXIST)
                                errx(1, "daemon already running, pid: %jd.",
                                    (intmax_t)otherpid);
                        warn("cannot open pid file");
                }
        }
        if (debug == 0 && nofork == 0) {
                daemon(0, 0);
                (void)signal(SIGHUP, SIG_IGN);
                (void)signal(SIGINT, SIG_IGN);
                /*
                 * nfsd sits in the kernel most of the time.  It needs
                 * to ignore SIGTERM/SIGQUIT in order to stay alive as long
                 * as possible during a shutdown, otherwise loopback
                 * mounts will not be able to unmount. 
                 */
                (void)signal(SIGTERM, SIG_IGN);
                (void)signal(SIGQUIT, SIG_IGN);
        }
        (void)signal(SIGSYS, nonfs);
        (void)signal(SIGCHLD, reapchild);
        (void)signal(SIGUSR2, backup_stable);

        openlog("nfsd", LOG_PID | (debug ? LOG_PERROR : 0), LOG_DAEMON);

        if (masterpidfh != NULL && pidfile_write(masterpidfh) != 0)
                syslog(LOG_ERR, "pidfile_write(): %m");

        /*
         * For V4, we open the stablerestart file and call nfssvc()
         * to get it loaded. This is done before the daemons do the
         * regular nfssvc() call to service NFS requests.
         * (This way the file remains open until the last nfsd is killed
         *  off.)
         * It and the backup copy will be created as empty files
         * the first time this nfsd is started and should never be
         * deleted/replaced if at all possible. It should live on a
         * local, non-volatile storage device that does not do hardware
         * level write-back caching. (See SCSI doc for more information
         * on how to prevent write-back caching on SCSI disks.)
         */
        open_stable(&stablefd, &backupfd);
        if (stablefd < 0) {
                syslog(LOG_ERR, "Can't open %s: %m\n", NFSD_STABLERESTART);
                exit(1);
        }
        /* This system call will fail for old kernels, but that's ok. */
        nfssvc(NFSSVC_BACKUPSTABLE, NULL);
        if (nfssvc(NFSSVC_STABLERESTART, (caddr_t)&stablefd) < 0) {
                if (errno == EPERM) {
                        jailed = 0;
                        jailed_size = sizeof(jailed);
                        sysctlbyname("security.jail.jailed", &jailed,
                            &jailed_size, NULL, 0);
                        if (jailed != 0)
                                syslog(LOG_ERR, "nfssvc stablerestart failed: "
                                    "allow.nfsd might not be configured");
                        else
                                syslog(LOG_ERR, "nfssvc stablerestart failed");
                } else if (errno == ENXIO)
                        syslog(LOG_ERR, "nfssvc stablerestart failed: is nfsd "
                            "already running?");
                else
                        syslog(LOG_ERR, "Can't read stable storage file: %m\n");
                exit(1);
        }
        nfssvc_addsock = NFSSVC_NFSDADDSOCK;
        nfssvc_nfsd = NFSSVC_NFSDNFSD | NFSSVC_NEWSTRUCT;

        if (tcpflag) {
                /*
                 * For TCP mode, we fork once to start the first
                 * kernel nfsd thread. The kernel will add more
                 * threads as needed.
                 */
                masterpid = getpid();
                pid = fork();
                if (pid == -1) {
                        syslog(LOG_ERR, "fork: %m");
                        nfsd_exit(1);
                }
                if (pid) {
                        children[0] = pid;
                } else {
                        pidfile_close(masterpidfh);
                        (void)signal(SIGUSR1, child_cleanup);
                        setproctitle("server");
                        start_server(0, &nfsdargs, vhostname);
                }
        }

        (void)signal(SIGUSR1, cleanup);
        FD_ZERO(&sockbits);
 
        rpcbregcnt = 0;
        /* Set up the socket for udp and rpcb register it. */
        if (udpflag) {
                rpcbreg = 0;
                for (i = 0; i < bindhostc; i++) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET;
                        hints.ai_socktype = SOCK_DGRAM;
                        hints.ai_protocol = IPPROTO_UDP;
                        if (setbindhost(&ai_udp, bindhost[i], hints) == 0) {
                                rpcbreg = 1;
                                rpcbregcnt++;
                                if ((sock = socket(ai_udp->ai_family,
                                    ai_udp->ai_socktype,
                                    ai_udp->ai_protocol)) < 0) {
                                        syslog(LOG_ERR,
                                            "can't create udp socket");
                                        nfsd_exit(1);
                                }
                                if (bind(sock, ai_udp->ai_addr,
                                    ai_udp->ai_addrlen) < 0) {
                                        syslog(LOG_ERR,
                                            "can't bind udp addr %s: %m",
                                            bindhost[i]);
                                        nfsd_exit(1);
                                }
                                freeaddrinfo(ai_udp);
                                addsockargs.sock = sock;
                                addsockargs.name = NULL;
                                addsockargs.namelen = 0;
                                if (nfssvc(nfssvc_addsock, &addsockargs) < 0) {
                                        syslog(LOG_ERR, "can't Add UDP socket");
                                        nfsd_exit(1);
                                }
                                (void)close(sock);
                        }
                }
                if (rpcbreg == 1) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET;
                        hints.ai_socktype = SOCK_DGRAM;
                        hints.ai_protocol = IPPROTO_UDP;
                        ecode = getaddrinfo(NULL, "nfs", &hints, &ai_udp);
                        if (ecode != 0) {
                                syslog(LOG_ERR, "getaddrinfo udp: %s",
                                   gai_strerror(ecode));
                                nfsd_exit(1);
                        }
                        nconf_udp = getnetconfigent("udp");
                        if (nconf_udp == NULL) {
                                syslog(LOG_ERR, "getnetconfigent udp failed");
                                nfsd_exit(1);
                        }
                        nb_udp.buf = ai_udp->ai_addr;
                        nb_udp.len = nb_udp.maxlen = ai_udp->ai_addrlen;
                        if (nfs_minvers == NFS_VER2)
                                if (!rpcb_set(NFS_PROGRAM, 2, nconf_udp,
                                    &nb_udp)) {
                                        syslog(LOG_ERR, "rpcb_set udp failed");
                                        nfsd_exit(1);
                                }
                        if (nfs_minvers <= NFS_VER3)
                                if (!rpcb_set(NFS_PROGRAM, 3, nconf_udp,
                                    &nb_udp)) {
                                        syslog(LOG_ERR, "rpcb_set udp failed");
                                        nfsd_exit(1);
                                }
                        freeaddrinfo(ai_udp);
                }
        }

        /* Set up the socket for udp6 and rpcb register it. */
        if (udpflag && ip6flag) {
                rpcbreg = 0;
                for (i = 0; i < bindhostc; i++) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET6;
                        hints.ai_socktype = SOCK_DGRAM;
                        hints.ai_protocol = IPPROTO_UDP;
                        if (setbindhost(&ai_udp6, bindhost[i], hints) == 0) {
                                rpcbreg = 1;
                                rpcbregcnt++;
                                if ((sock = socket(ai_udp6->ai_family,
                                    ai_udp6->ai_socktype,
                                    ai_udp6->ai_protocol)) < 0) {
                                        syslog(LOG_ERR,
                                                "can't create udp6 socket");
                                        nfsd_exit(1);
                                }
                                if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY,
                                    &on, sizeof on) < 0) {
                                        syslog(LOG_ERR,
                                            "can't set v6-only binding for "
                                            "udp6 socket: %m");
                                        nfsd_exit(1);
                                }
                                if (bind(sock, ai_udp6->ai_addr,
                                    ai_udp6->ai_addrlen) < 0) {
                                        syslog(LOG_ERR,
                                            "can't bind udp6 addr %s: %m",
                                            bindhost[i]);
                                        nfsd_exit(1);
                                }
                                freeaddrinfo(ai_udp6);
                                addsockargs.sock = sock;
                                addsockargs.name = NULL;
                                addsockargs.namelen = 0;
                                if (nfssvc(nfssvc_addsock, &addsockargs) < 0) {
                                        syslog(LOG_ERR,
                                            "can't add UDP6 socket");
                                        nfsd_exit(1);
                                }
                                (void)close(sock);    
                        }
                }
                if (rpcbreg == 1) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET6;
                        hints.ai_socktype = SOCK_DGRAM;
                        hints.ai_protocol = IPPROTO_UDP;
                        ecode = getaddrinfo(NULL, "nfs", &hints, &ai_udp6);
                        if (ecode != 0) {
                                syslog(LOG_ERR, "getaddrinfo udp6: %s",
                                   gai_strerror(ecode));
                                nfsd_exit(1);
                        }
                        nconf_udp6 = getnetconfigent("udp6");
                        if (nconf_udp6 == NULL) {
                                syslog(LOG_ERR, "getnetconfigent udp6 failed");
                                nfsd_exit(1);
                        }
                        nb_udp6.buf = ai_udp6->ai_addr;
                        nb_udp6.len = nb_udp6.maxlen = ai_udp6->ai_addrlen;
                        if (nfs_minvers == NFS_VER2)
                                if (!rpcb_set(NFS_PROGRAM, 2, nconf_udp6,
                                    &nb_udp6)) {
                                        syslog(LOG_ERR,
                                            "rpcb_set udp6 failed");
                                        nfsd_exit(1);
                                }
                        if (nfs_minvers <= NFS_VER3)
                                if (!rpcb_set(NFS_PROGRAM, 3, nconf_udp6,
                                    &nb_udp6)) {
                                        syslog(LOG_ERR,
                                            "rpcb_set udp6 failed");
                                        nfsd_exit(1);
                                }
                        freeaddrinfo(ai_udp6);
                }
        }

        /* Set up the socket for tcp and rpcb register it. */
        if (tcpflag) {
                rpcbreg = 0;
                for (i = 0; i < bindhostc; i++) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET;
                        hints.ai_socktype = SOCK_STREAM;
                        hints.ai_protocol = IPPROTO_TCP;
                        if (setbindhost(&ai_tcp, bindhost[i], hints) == 0) {
                                rpcbreg = 1;
                                rpcbregcnt++;
                                if ((tcpsock = socket(AF_INET, SOCK_STREAM,
                                    0)) < 0) {
                                        syslog(LOG_ERR,
                                            "can't create tcp socket");
                                        nfsd_exit(1);
                                }
                                if (setsockopt(tcpsock, SOL_SOCKET,
                                    SO_REUSEADDR,
                                    (char *)&on, sizeof(on)) < 0)
                                        syslog(LOG_ERR,
                                             "setsockopt SO_REUSEADDR: %m");
                                if (bind(tcpsock, ai_tcp->ai_addr,
                                    ai_tcp->ai_addrlen) < 0) {
                                        syslog(LOG_ERR,
                                            "can't bind tcp addr %s: %m",
                                            bindhost[i]);
                                        nfsd_exit(1);
                                }
                                if (listen(tcpsock, -1) < 0) {
                                        syslog(LOG_ERR, "listen failed");
                                        nfsd_exit(1);
                                }
                                freeaddrinfo(ai_tcp);
                                FD_SET(tcpsock, &sockbits);
                                maxsock = tcpsock;
                                connect_type_cnt++;
                        }
                }
                if (rpcbreg == 1) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET;
                        hints.ai_socktype = SOCK_STREAM;
                        hints.ai_protocol = IPPROTO_TCP;
                        ecode = getaddrinfo(NULL, "nfs", &hints,
                             &ai_tcp);
                        if (ecode != 0) {
                                syslog(LOG_ERR, "getaddrinfo tcp: %s",
                                   gai_strerror(ecode));
                                nfsd_exit(1);
                        }
                        nconf_tcp = getnetconfigent("tcp");
                        if (nconf_tcp == NULL) {
                                syslog(LOG_ERR, "getnetconfigent tcp failed");
                                nfsd_exit(1);
                        }
                        nb_tcp.buf = ai_tcp->ai_addr;
                        nb_tcp.len = nb_tcp.maxlen = ai_tcp->ai_addrlen;
                        if (nfs_minvers == NFS_VER2)
                                if (!rpcb_set(NFS_PROGRAM, 2, nconf_tcp,
                                    &nb_tcp)) {
                                        syslog(LOG_ERR, "rpcb_set tcp failed");
                                        nfsd_exit(1);
                                }
                        if (nfs_minvers <= NFS_VER3)
                                if (!rpcb_set(NFS_PROGRAM, 3, nconf_tcp,
                                    &nb_tcp)) {
                                        syslog(LOG_ERR, "rpcb_set tcp failed");
                                        nfsd_exit(1);
                                }
                        freeaddrinfo(ai_tcp);
                }
        }

        /* Set up the socket for tcp6 and rpcb register it. */
        if (tcpflag && ip6flag) {
                rpcbreg = 0;
                for (i = 0; i < bindhostc; i++) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET6;
                        hints.ai_socktype = SOCK_STREAM;
                        hints.ai_protocol = IPPROTO_TCP;
                        if (setbindhost(&ai_tcp6, bindhost[i], hints) == 0) {
                                rpcbreg = 1;
                                rpcbregcnt++;
                                if ((tcp6sock = socket(ai_tcp6->ai_family,
                                    ai_tcp6->ai_socktype,
                                    ai_tcp6->ai_protocol)) < 0) {
                                        syslog(LOG_ERR,
                                            "can't create tcp6 socket");
                                        nfsd_exit(1);
                                }
                                if (setsockopt(tcp6sock, SOL_SOCKET,
                                    SO_REUSEADDR,
                                    (char *)&on, sizeof(on)) < 0)
                                        syslog(LOG_ERR,
                                            "setsockopt SO_REUSEADDR: %m");
                                if (setsockopt(tcp6sock, IPPROTO_IPV6,
                                    IPV6_V6ONLY, &on, sizeof on) < 0) {
                                        syslog(LOG_ERR,
                                        "can't set v6-only binding for tcp6 "
                                            "socket: %m");
                                        nfsd_exit(1);
                                }
                                if (bind(tcp6sock, ai_tcp6->ai_addr,
                                    ai_tcp6->ai_addrlen) < 0) {
                                        syslog(LOG_ERR,
                                            "can't bind tcp6 addr %s: %m",
                                            bindhost[i]);
                                        nfsd_exit(1);
                                }
                                if (listen(tcp6sock, -1) < 0) {
                                        syslog(LOG_ERR, "listen failed");
                                        nfsd_exit(1);
                                }
                                freeaddrinfo(ai_tcp6);
                                FD_SET(tcp6sock, &sockbits);
                                if (maxsock < tcp6sock)
                                        maxsock = tcp6sock;
                                connect_type_cnt++;
                        }
                }
                if (rpcbreg == 1) {
                        memset(&hints, 0, sizeof hints);
                        hints.ai_flags = AI_PASSIVE;
                        hints.ai_family = AF_INET6;
                        hints.ai_socktype = SOCK_STREAM;
                        hints.ai_protocol = IPPROTO_TCP;
                        ecode = getaddrinfo(NULL, "nfs", &hints, &ai_tcp6);
                        if (ecode != 0) {
                                syslog(LOG_ERR, "getaddrinfo tcp6: %s",
                                   gai_strerror(ecode));
                                nfsd_exit(1);
                        }
                        nconf_tcp6 = getnetconfigent("tcp6");
                        if (nconf_tcp6 == NULL) {
                                syslog(LOG_ERR, "getnetconfigent tcp6 failed");
                                nfsd_exit(1);
                        }
                        nb_tcp6.buf = ai_tcp6->ai_addr;
                        nb_tcp6.len = nb_tcp6.maxlen = ai_tcp6->ai_addrlen;
                        if (nfs_minvers == NFS_VER2)
                                if (!rpcb_set(NFS_PROGRAM, 2, nconf_tcp6,
                                    &nb_tcp6)) {
                                        syslog(LOG_ERR, "rpcb_set tcp6 failed");
                                        nfsd_exit(1);
                                }
                        if (nfs_minvers <= NFS_VER3)
                                if (!rpcb_set(NFS_PROGRAM, 3, nconf_tcp6,
                                    &nb_tcp6)) {
                                        syslog(LOG_ERR, "rpcb_set tcp6 failed");
                                        nfsd_exit(1);
                                }
                        freeaddrinfo(ai_tcp6);
                }
        }

        if (rpcbregcnt == 0) {
                syslog(LOG_ERR, "rpcb_set() failed, nothing to do: %m");
                nfsd_exit(1);
        }

        if (tcpflag && connect_type_cnt == 0) {
                syslog(LOG_ERR, "tcp connects == 0, nothing to do: %m");
                nfsd_exit(1);
        }

        setproctitle("master");
        /*
         * We always want a master to have a clean way to shut nfsd down
         * (with unregistration): if the master is killed, it unregisters and
         * kills all children. If we run for UDP only (and so do not have to
         * loop waiting for accept), we instead make the parent
         * a "server" too. start_server will not return.
         */
        if (!tcpflag)
                start_server(1, &nfsdargs, vhostname);

        /*
         * Loop forever accepting connections and passing the sockets
         * into the kernel for the mounts.
         */
        for (;;) {
                ready = sockbits;
                if (connect_type_cnt > 1) {
                        if (select(maxsock + 1,
                            &ready, NULL, NULL, NULL) < 1) {
                                error = errno;
                                if (error == EINTR)
                                        continue;
                                syslog(LOG_ERR, "select failed: %m");
                                nfsd_exit(1);
                        }
                }
                for (tcpsock = 0; tcpsock <= maxsock; tcpsock++) {
                        if (FD_ISSET(tcpsock, &ready)) {
                                len = sizeof(peer);
                                if ((msgsock = accept(tcpsock,
                                    (struct sockaddr *)&peer, &len)) < 0) {
                                        error = errno;
                                        syslog(LOG_ERR, "accept failed: %m");
                                        if (error == ECONNABORTED ||
                                            error == EINTR)
                                                continue;
                                        nfsd_exit(1);
                                }
                                if (setsockopt(msgsock, SOL_SOCKET,
                                    SO_KEEPALIVE, (char *)&on, sizeof(on)) < 0)
                                        syslog(LOG_ERR,
                                            "setsockopt SO_KEEPALIVE: %m");
                                addsockargs.sock = msgsock;
                                addsockargs.name = (caddr_t)&peer;
                                addsockargs.namelen = len;
                                nfssvc(nfssvc_addsock, &addsockargs);
                                (void)close(msgsock);
                        }
                }
        }
}

static int
setbindhost(struct addrinfo **ai, const char *bindhost, struct addrinfo hints)
{
        int ecode;
        u_int32_t host_addr[4];  /* IPv4 or IPv6 */
        const char *hostptr;

        if (bindhost == NULL || strcmp("*", bindhost) == 0)
                hostptr = NULL;
        else
                hostptr = bindhost;

        if (hostptr != NULL) {
                switch (hints.ai_family) {
                case AF_INET:
                        if (inet_pton(AF_INET, hostptr, host_addr) == 1) {
                                hints.ai_flags = AI_NUMERICHOST;
                        } else {
                                if (inet_pton(AF_INET6, hostptr,
                                    host_addr) == 1)
                                        return (1);
                        }
                        break;
                case AF_INET6:
                        if (inet_pton(AF_INET6, hostptr, host_addr) == 1) {
                                hints.ai_flags = AI_NUMERICHOST;
                        } else {
                                if (inet_pton(AF_INET, hostptr,
                                    host_addr) == 1)
                                        return (1);
                        }
                        break;
                default:
                        break;
                }
        }
        
        ecode = getaddrinfo(hostptr, "nfs", &hints, ai);
        if (ecode != 0) {
                syslog(LOG_ERR, "getaddrinfo %s: %s", bindhost,
                    gai_strerror(ecode));
                return (1);
        }
        return (0);
}

static void
set_nfsdcnt(int proposed)
{

        if (proposed < 1) {
                warnx("nfsd count too low %d; reset to %d", proposed,
                    DEFNFSDCNT);
                nfsdcnt = DEFNFSDCNT;
        } else if (proposed > MAXNFSDCNT) {
                warnx("nfsd count too high %d; truncated to %d", proposed,
                    MAXNFSDCNT);
                nfsdcnt = MAXNFSDCNT;
        } else
                nfsdcnt = proposed;
        nfsdcnt_set = 1;
}

static void
usage(void)
{
        (void)fprintf(stderr, "%s", getopt_usage);
        exit(1);
}

static void
nonfs(__unused int signo)
{
        syslog(LOG_ERR, "missing system call: NFS not available");
}

static void
reapchild(__unused int signo)
{
        pid_t pid;
        int i;

        while ((pid = wait3(NULL, WNOHANG, NULL)) > 0) {
                for (i = 0; i < nfsdcnt; i++)
                        if (pid == children[i])
                                children[i] = -1;
        }
}

static void
unregistration(void)
{
        if ((nfs_minvers == NFS_VER2 && !rpcb_unset(NFS_PROGRAM, 2, NULL)) ||
            (nfs_minvers <= NFS_VER3 && !rpcb_unset(NFS_PROGRAM, 3, NULL)))
                syslog(LOG_ERR, "rpcb_unset failed");
}

static void
killchildren(void)
{
        int i;

        for (i = 0; i < nfsdcnt; i++) {
                if (children[i] > 0)
                        kill(children[i], SIGKILL);
        }
}

/*
 * Cleanup master after SIGUSR1.
 */
static void
cleanup(__unused int signo)
{
        nfsd_exit(0);
}

/*
 * Cleanup child after SIGUSR1.
 */
static void
child_cleanup(__unused int signo)
{
        exit(0);
}

static void
nfsd_exit(int status)
{
        killchildren();
        unregistration();
        if (masterpidfh != NULL)
                pidfile_remove(masterpidfh);
        exit(status);
}

static int
get_tuned_nfsdcount(void)
{
        int ncpu, error, tuned_nfsdcnt;
        size_t ncpu_size;

        ncpu_size = sizeof(ncpu);
        error = sysctlbyname("hw.ncpu", &ncpu, &ncpu_size, NULL, 0);
        if (error) {
                warnx("sysctlbyname(hw.ncpu) failed defaulting to %d nfs servers",
                    DEFNFSDCNT);
                tuned_nfsdcnt = DEFNFSDCNT;
        } else {
                tuned_nfsdcnt = ncpu * 8;
        }
        return tuned_nfsdcnt;
}

static void
start_server(int master, struct nfsd_nfsd_args *nfsdargp, const char *vhost)
{
        char principal[MAXHOSTNAMELEN + 5];
        int status, error;
        char hostname[MAXHOSTNAMELEN + 1], *cp;
        struct addrinfo *aip, hints;

        status = 0;
        if (vhost == NULL)
                gethostname(hostname, sizeof (hostname));
        else
                strlcpy(hostname, vhost, sizeof (hostname));
        snprintf(principal, sizeof (principal), "nfs@%s", hostname);
        if ((cp = strchr(hostname, '.')) == NULL ||
            *(cp + 1) == '\0') {
                /* If not fully qualified, try getaddrinfo() */
                memset((void *)&hints, 0, sizeof (hints));
                hints.ai_flags = AI_CANONNAME;
                error = getaddrinfo(hostname, NULL, &hints, &aip);
                if (error == 0) {
                        if (aip->ai_canonname != NULL &&
                            (cp = strchr(aip->ai_canonname, '.')) !=
                            NULL && *(cp + 1) != '\0')
                                snprintf(principal, sizeof (principal),
                                    "nfs@%s", aip->ai_canonname);
                        freeaddrinfo(aip);
                }
        }
        nfsdargp->principal = principal;

        if (nfsdcnt_set)
                nfsdargp->minthreads = nfsdargp->maxthreads = nfsdcnt;
        else {
                nfsdargp->minthreads = minthreads_set ? minthreads : get_tuned_nfsdcount();
                nfsdargp->maxthreads = maxthreads_set ? maxthreads : nfsdargp->minthreads;
                if (nfsdargp->maxthreads < nfsdargp->minthreads)
                        nfsdargp->maxthreads = nfsdargp->minthreads;
        }
        error = nfssvc(nfssvc_nfsd, nfsdargp);
        if (error < 0 && errno == EAUTH) {
                /*
                 * This indicates that it could not register the
                 * rpcsec_gss credentials, usually because the
                 * gssd daemon isn't running.
                 * (only the experimental server with nfsv4)
                 */
                syslog(LOG_ERR, "No gssd, using AUTH_SYS only");
                principal[0] = '\0';
                error = nfssvc(nfssvc_nfsd, nfsdargp);
        }
        if (error < 0) {
                if (errno == ENXIO) {
                        syslog(LOG_ERR, "Bad -p option, cannot run");
                        if (masterpid != 0 && master == 0)
                                kill(masterpid, SIGUSR1);
                } else
                        syslog(LOG_ERR, "nfssvc: %m");
                status = 1;
        }
        if (master)
                nfsd_exit(status);
        else
                exit(status);
}

/*
 * Open the stable restart file and return the file descriptor for it.
 */
static void
open_stable(int *stable_fdp, int *backup_fdp)
{
        int stable_fd, backup_fd = -1, ret;
        struct stat st, backup_st;

        /* Open and stat the stable restart file. */
        stable_fd = open(NFSD_STABLERESTART, O_RDWR, 0);
        if (stable_fd < 0)
                stable_fd = open(NFSD_STABLERESTART, O_RDWR | O_CREAT, 0600);
        if (stable_fd >= 0) {
                ret = fstat(stable_fd, &st);
                if (ret < 0) {
                        close(stable_fd);
                        stable_fd = -1;
                }
        }

        /* Open and stat the backup stable restart file. */
        if (stable_fd >= 0) {
                backup_fd = open(NFSD_STABLEBACKUP, O_RDWR, 0);
                if (backup_fd < 0)
                        backup_fd = open(NFSD_STABLEBACKUP, O_RDWR | O_CREAT,
                            0600);
                if (backup_fd >= 0) {
                        ret = fstat(backup_fd, &backup_st);
                        if (ret < 0) {
                                close(backup_fd);
                                backup_fd = -1;
                        }
                }
                if (backup_fd < 0) {
                        close(stable_fd);
                        stable_fd = -1;
                }
        }

        *stable_fdp = stable_fd;
        *backup_fdp = backup_fd;
        if (stable_fd < 0)
                return;

        /* Sync up the 2 files, as required. */
        if (st.st_size > 0)
                copy_stable(stable_fd, backup_fd);
        else if (backup_st.st_size > 0)
                copy_stable(backup_fd, stable_fd);
}

/*
 * Copy the stable restart file to the backup or vice versa.
 */
static void
copy_stable(int from_fd, int to_fd)
{
        int cnt, ret;
        static char buf[1024];

        ret = lseek(from_fd, (off_t)0, SEEK_SET);
        if (ret >= 0)
                ret = lseek(to_fd, (off_t)0, SEEK_SET);
        if (ret >= 0)
                ret = ftruncate(to_fd, (off_t)0);
        if (ret >= 0)
                do {
                        cnt = read(from_fd, buf, 1024);
                        if (cnt > 0)
                                ret = write(to_fd, buf, cnt);
                        else if (cnt < 0)
                                ret = cnt;
                } while (cnt > 0 && ret >= 0);
        if (ret >= 0)
                ret = fsync(to_fd);
        if (ret < 0)
                syslog(LOG_ERR, "stable restart copy failure: %m");
}

/*
 * Back up the stable restart file when indicated by the kernel.
 */
static void
backup_stable(__unused int signo)
{

        if (stablefd >= 0)
                copy_stable(stablefd, backupfd);
}

/*
 * Parse the pNFS string and extract the DS servers and ports numbers.
 */
static void
parse_dsserver(const char *optionarg, struct nfsd_nfsd_args *nfsdargp)
{
        char *cp, *cp2, *dsaddr, *dshost, *dspath, *dsvol, nfsprt[9];
        char *mdspath, *mdsp, ip6[INET6_ADDRSTRLEN];
        const char *ad;
        int ecode;
        u_int adsiz, dsaddrcnt, dshostcnt, dspathcnt, hostsiz, pathsiz;
        u_int mdspathcnt;
        size_t dsaddrsiz, dshostsiz, dspathsiz, nfsprtsiz, mdspathsiz;
        struct addrinfo hints, *ai_tcp, *res;
        struct sockaddr_in sin;
        struct sockaddr_in6 sin6;

        cp = strdup(optionarg);
        if (cp == NULL)
                errx(1, "Out of memory");

        /* Now, do the host names. */
        dspathsiz = 1024;
        dspathcnt = 0;
        dspath = malloc(dspathsiz);
        if (dspath == NULL)
                errx(1, "Out of memory");
        dshostsiz = 1024;
        dshostcnt = 0;
        dshost = malloc(dshostsiz);
        if (dshost == NULL)
                errx(1, "Out of memory");
        dsaddrsiz = 1024;
        dsaddrcnt = 0;
        dsaddr = malloc(dsaddrsiz);
        if (dsaddr == NULL)
                errx(1, "Out of memory");
        mdspathsiz = 1024;
        mdspathcnt = 0;
        mdspath = malloc(mdspathsiz);
        if (mdspath == NULL)
                errx(1, "Out of memory");

        /* Put the NFS port# in "." form. */
        snprintf(nfsprt, 9, ".%d.%d", 2049 >> 8, 2049 & 0xff);
        nfsprtsiz = strlen(nfsprt);

        ai_tcp = NULL;
        /* Loop around for each DS server name. */
        do {
                cp2 = strchr(cp, ',');
                if (cp2 != NULL) {
                        /* Not the last DS in the list. */
                        *cp2++ = '\0';
                        if (*cp2 == '\0')
                                usage();
                }

                dsvol = strchr(cp, ':');
                if (dsvol == NULL || *(dsvol + 1) == '\0')
                        usage();
                *dsvol++ = '\0';

                /* Optional path for MDS file system to be stored on DS. */
                mdsp = strchr(dsvol, '#');
                if (mdsp != NULL) {
                        if (*(mdsp + 1) == '\0' || mdsp <= dsvol)
                                usage();
                        *mdsp++ = '\0';
                }

                /* Append this pathname to dspath. */
                pathsiz = strlen(dsvol);
                if (dspathcnt + pathsiz + 1 > dspathsiz) {
                        dspathsiz *= 2;
                        dspath = realloc(dspath, dspathsiz);
                        if (dspath == NULL)
                                errx(1, "Out of memory");
                }
                strcpy(&dspath[dspathcnt], dsvol);
                dspathcnt += pathsiz + 1;

                /* Append this pathname to mdspath. */
                if (mdsp != NULL)
                        pathsiz = strlen(mdsp);
                else
                        pathsiz = 0;
                if (mdspathcnt + pathsiz + 1 > mdspathsiz) {
                        mdspathsiz *= 2;
                        mdspath = realloc(mdspath, mdspathsiz);
                        if (mdspath == NULL)
                                errx(1, "Out of memory");
                }
                if (mdsp != NULL)
                        strcpy(&mdspath[mdspathcnt], mdsp);
                else
                        mdspath[mdspathcnt] = '\0';
                mdspathcnt += pathsiz + 1;

                if (ai_tcp != NULL)
                        freeaddrinfo(ai_tcp);

                /* Get the fully qualified domain name and IP address. */
                memset(&hints, 0, sizeof(hints));
                hints.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
                hints.ai_family = PF_UNSPEC;
                hints.ai_socktype = SOCK_STREAM;
                hints.ai_protocol = IPPROTO_TCP;
                ecode = getaddrinfo(cp, NULL, &hints, &ai_tcp);
                if (ecode != 0)
                        err(1, "getaddrinfo pnfs: %s %s", cp,
                            gai_strerror(ecode));
                ad = NULL;
                for (res = ai_tcp; res != NULL; res = res->ai_next) {
                        if (res->ai_addr->sa_family == AF_INET) {
                                if (res->ai_addrlen < sizeof(sin))
                                        err(1, "getaddrinfo() returned "
                                            "undersized IPv4 address");
                                /*
                                 * Mips cares about sockaddr_in alignment,
                                 * so copy the address.
                                 */
                                memcpy(&sin, res->ai_addr, sizeof(sin));
                                ad = inet_ntoa(sin.sin_addr);
                                break;
                        } else if (res->ai_family == AF_INET6) {
                                if (res->ai_addrlen < sizeof(sin6))
                                        err(1, "getaddrinfo() returned "
                                            "undersized IPv6 address");
                                /*
                                 * Mips cares about sockaddr_in6 alignment,
                                 * so copy the address.
                                 */
                                memcpy(&sin6, res->ai_addr, sizeof(sin6));
                                ad = inet_ntop(AF_INET6, &sin6.sin6_addr, ip6,
                                    sizeof(ip6));

                                /*
                                 * XXX
                                 * Since a link local address will only
                                 * work if the client and DS are in the
                                 * same scope zone, only use it if it is
                                 * the only address.
                                 */
                                if (ad != NULL &&
                                    !IN6_IS_ADDR_LINKLOCAL(&sin6.sin6_addr))
                                        break;
                        }
                }
                if (ad == NULL)
                        err(1, "No IP address for %s", cp);

                /* Append this address to dsaddr. */
                adsiz = strlen(ad);
                if (dsaddrcnt + adsiz + nfsprtsiz + 1 > dsaddrsiz) {
                        dsaddrsiz *= 2;
                        dsaddr = realloc(dsaddr, dsaddrsiz);
                        if (dsaddr == NULL)
                                errx(1, "Out of memory");
                }
                strcpy(&dsaddr[dsaddrcnt], ad);
                strcat(&dsaddr[dsaddrcnt], nfsprt);
                dsaddrcnt += adsiz + nfsprtsiz + 1;

                /* Append this hostname to dshost. */
                hostsiz = strlen(ai_tcp->ai_canonname);
                if (dshostcnt + hostsiz + 1 > dshostsiz) {
                        dshostsiz *= 2;
                        dshost = realloc(dshost, dshostsiz);
                        if (dshost == NULL)
                                errx(1, "Out of memory");
                }
                strcpy(&dshost[dshostcnt], ai_tcp->ai_canonname);
                dshostcnt += hostsiz + 1;

                cp = cp2;
        } while (cp != NULL);

        nfsdargp->addr = dsaddr;
        nfsdargp->addrlen = dsaddrcnt;
        nfsdargp->dnshost = dshost;
        nfsdargp->dnshostlen = dshostcnt;
        nfsdargp->dspath = dspath;
        nfsdargp->dspathlen = dspathcnt;
        nfsdargp->mdspath = mdspath;
        nfsdargp->mdspathlen = mdspathcnt;
        freeaddrinfo(ai_tcp);
}