cmd/rexd/mount_nfs.c

	mount_nfs.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */

/*
 *  mount_nfs.c - procedural interface to the NFS mount operation
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#define NFSCLIENT
#include    <sys/types.h>
#include    <memory.h>
#include    <netconfig.h>
#include    <netdb.h>
#include    <netdir.h>
#include    <netinet/in.h>
#include    <stdarg.h>
#include    <stdio.h>
#include    <stdlib.h>
#include    <string.h>
#include    <unistd.h>
#include    <syslog.h>

#include    <rpc/rpc.h>
#include    <rpc/clnt_soc.h>
#include    <rpc/pmap_prot.h>
#include    <nfs/nfs.h>
#include    <nfs/mount.h>
#include    <rpcsvc/mount.h>
#include    <errno.h>
#include    <sys/mntent.h>
#include    <sys/mnttab.h>
#include    <sys/mount.h>
#include    <sys/param.h>
#include    <sys/socket.h>
#include    <sys/stat.h>

#define TIME_MAX    16

extern  int Debug;
extern  time_t  time_now;

extern  FILE    *setmntent(char *, char *);
extern  void    errprintf(char *, char *, ...);

FILE        *setmntent(char *, char *);
void        endmntent(FILE *);
enum clnt_stat  pingnfs(char *, rpcvers_t *);
struct netbuf   *get_addr(char *, int, int, struct netconfig **);
struct knetconfig *get_knconf(struct netconfig *);
void        netbuf_free(struct netbuf *);
void        free_knconf(struct knetconfig *);

/*
 * mount_nfs - mount a file system using NFS
 *
 * Returns: 0 if OK, 1 if error.
 *  The "error" string returns the error message.
 */
int
mount_nfs(fsname, dir, error)
    char *fsname;
    char *dir;
    char *error;
{
    struct sockaddr_in sin;
    struct hostent *hp;
    struct fhstatus fhs;
    char host[256];
    char *path;
    char opts[32];
    struct stat st;
    int s = -1;
    struct timeval timeout;
    CLIENT *client;
    enum clnt_stat rpc_stat;
    int printed1 = 0;
    int printed2 = 0;
    unsigned winks = 1; /* seconds of sleep time */
    struct mnttab mnt;
    FILE *mnted;
    int flags;
    struct nfs_args args;
    struct netconfig *nconf, *udpnconf;
    char tbuf[TIME_MAX];
    rpcvers_t vers;
    rpcvers_t nfsvers;
    char *fstype;
    struct mountres3 res3;
    nfs_fh3 fh3;
    int *auths;
    int count;

    if (Debug)
        printf("mount_nfs request: mount %s\tdir %s\n", fsname, dir);

    if (Debug && errno)
        printf("ERRNO set on mount_nfs entry: %d\n", errno);

    path = strchr(fsname, ':');
    if (path == NULL) {
        errprintf(error, "No host name in %s\n", fsname);
        return (1);
    }
    *path = '\0';
    strcpy(host, fsname);
    *path++ = ':';
    if (*path == '\0') {
        /*
         * handle the special case of importing a root file system
         */
        strcpy(path, "/");
    }

    if (Debug) {
        printf("mount_nfs:\tpath == %s\n", path);
        printf("\t\tdir == %s\n", dir);
        printf("\t\tgethostbyname host == %s\n", host);
    }

    /*
     * Get server's address
     */
    if ((hp = gethostbyname(host)) == NULL) {
        errprintf(error, "mount %s: %s not in hosts database\n",
            fsname, host);
        return (1);
    }

    if (Debug && errno)
        printf("ERRNO set after gethostbyname: %d\n", errno);

    if (Debug) {
        fprintf(stderr, "gethostbyname:\n\th_name %s\n\t", hp->h_name);
        if (hp->h_aliases[0] && *hp->h_aliases[0])
            fprintf(stderr, "h_aliases %s\n\t", hp->h_aliases[0]);
        else
            fprintf(stderr, "h_aliases %s\n\t", "<none>");
        if (hp->h_addrtype == AF_INET)
            fprintf(stderr,
                "h_addrtype AF_INET\n\th_adth_length %u\n\t",
                hp->h_length);
        else
            fprintf(stderr, "h_addrtype %u\n\th_adth_length %u\n\t",
                hp->h_addrtype, hp->h_length);
        if (hp->h_addr_list[0] && *hp->h_addr_list[0])
            fprintf(stderr, "h_addr_list <apparent list>\n");
        else
            fprintf(stderr, "h_addr_list %s\n", "<none>");
    }

    if (pingnfs(host, &nfsvers) != RPC_SUCCESS) {
        errprintf(error, "host %s not responding to ping\n", host);
        return (1);
    }

    if (Debug)
        printf("pingnfs: succeeds.\n");

    vers = nfsvers;

    if (Debug)
        printf("clnt_create for mountproc (%d)\n", errno);

    client = clnt_create_vers(host, MOUNTPROG, &vers, MOUNTVERS, vers,
                "udp");
    if (client == NULL) {
        errprintf(error, "%s %s\n", host,
              clnt_spcreateerror("mount server not responding"));
        return (1);
    }

    if (Debug)
        printf("call bindudp_resvport for mountproc (%d)\n", errno);

    if (bindudp_resvport(client) < 0) {
        errprintf(error, "mount %s:%s: %s\n", host, path,
              "Couldn't bind to reserved port");
        if (Debug)
            printf("could not bind to reserved port\n");
        clnt_destroy(client);
        return (1);
    }

    if (client->cl_auth)
        auth_destroy(client->cl_auth);
    if ((client->cl_auth = authsys_create_default()) == NULL) {
        errprintf(error, "mount %s:%s: %s\n", host, path,
              "Couldn't create authsys structure");
        if (Debug)
            printf("could not create authsys structure\n");
        clnt_destroy(client);
        return (1);
    }

/* #ifdef   NOWAY
/*  if (Debug)
/*      printf("authsys_create_default called for mountproc\n");
/*  client->cl_auth = authsys_create_default();
/* #endif
/* */

    /* set mount args */
    memset(&args, 0, sizeof(args));

    /* Get fhandle of remote path from server's mountd */

    timeout.tv_usec = 0;
    timeout.tv_sec = 25;

    switch (vers) {
    case MOUNTVERS:
    case MOUNTVERS_POSIX:
        rpc_stat = clnt_call(client, MOUNTPROC_MNT,
                xdr_dirpath, (caddr_t)&path,
                xdr_fhstatus, (caddr_t)&fhs, timeout);

        if (rpc_stat != RPC_SUCCESS) {
            /* Given the way "clnt_sperror" works, the "%s" */
            /* following the "not responding" is correct. */
            errprintf(error, "mount server %s not responding %s\n",
                host, clnt_sperror(client, ""));
            clnt_destroy(client);
            return (1);
        }

        clnt_destroy(client);

        if ((errno = fhs.fhs_status) != MNT_OK) {
            if (errno == EACCES) {
                errprintf(error,
                  "rexd mount: not in EXPORT list for %s\n",
                  fsname);
            } else {
                errprintf(error, "rexd mount: error %d %s\n",
                    errno, strerror(errno));
            }
            return (1);
        }

        args.fh = (caddr_t)&fhs.fhstatus_u.fhs_fhandle;
        fstype = MNTTYPE_NFS;
        break;
    case MOUNTVERS3:
        memset((char *)&res3, '\0', sizeof (res3));
        rpc_stat = clnt_call(client, MOUNTPROC_MNT,
                xdr_dirpath, (char *)&path,
                xdr_mountres3, (char *)&res3, timeout);

        if (rpc_stat != RPC_SUCCESS) {
            /* Given the way "clnt_sperror" works, the "%s" */
            /* following the "not responding" is correct. */
            errprintf(error, "mount server %s not responding %s\n",
                host, clnt_sperror(client, ""));
            clnt_destroy(client);
            return (1);
        }

        clnt_destroy(client);

        if ((errno = res3.fhs_status) != MNT_OK) {
            if (errno == EACCES) {
                errprintf(error,
                  "rexd mount: not in EXPORT list for %s\n",
                  fsname);
            } else {
                errprintf(error, "rexd mount: error %d %s\n",
                    errno, strerror(errno));
            }
            return (1);
        }

        auths =
            res3.mountres3_u.mountinfo.auth_flavors.auth_flavors_val;
        count =
            res3.mountres3_u.mountinfo.auth_flavors.auth_flavors_len;
        if (count > 0) {
            if (auths[0] == AUTH_DES)
                args.flags |= NFSMNT_SECURE;
        }

        fh3.fh3_length =
            res3.mountres3_u.mountinfo.fhandle.fhandle3_len;
        memcpy(fh3.fh3_u.data,
            res3.mountres3_u.mountinfo.fhandle.fhandle3_val,
            fh3.fh3_length);
        args.fh = (caddr_t)&fh3;
        fstype = MNTTYPE_NFS3;
        break;
    default:
        errprintf(error, "rexd mount: unknown MOUNT version %ld\n",
            vers);
        return (1);
    }


    /*
     * remote mount the fhandle on the local path.
     */

    args.hostname = host;
    args.flags = NFSMNT_HOSTNAME;
    args.flags |= NFSMNT_INT; /* default is "intr" */

    args.addr = get_addr(host, NFS_PROGRAM, nfsvers, &nconf);
    if (args.addr == NULL) {
        errprintf(error, "%s: no NFS service", host);
        return (1);
    }

    args.flags |=  NFSMNT_KNCONF;
    args.knconf = get_knconf(nconf);
    if (args.knconf == NULL) {
        netbuf_free(args.addr);
        return (1);
    }

    if (Debug)
        printf("start mount system call (%d)\n", errno);

    flags = MS_NOSUID | MS_DATA;

    /* Provide the mounted resource name when mounting. */
    if (mount(fsname, dir, flags, fstype, &args, sizeof(args)) < 0) {
        netbuf_free(args.addr);
        free_knconf(args.knconf);
        errprintf(error, "unable to mount %s on %s: %s\n",
            fsname, dir, strerror(errno));
        return (1);
    }

    if (Debug)
        printf("end mount system call (%d)\n", errno);

    /*
     * stat the new mount and get its dev
     */
    if (stat(dir, &st) < 0) {
        errprintf(error, "couldn't stat %s\n", dir);
        return (1);
    }

    if (Debug)
        printf("stat of new mount (%d)\n", errno);

    (void) sprintf(opts, "rw,noquota,hard,intr,dev=%x", st.st_dev);

    /*
     * update /etc/mtab
     */

    mnt.mnt_special = fsname;
    mnt.mnt_mountp = dir;
    mnt.mnt_fstype = MNTTYPE_NFS;
    mnt.mnt_mntopts = opts;
    (void) sprintf(tbuf, "%ld", time(0L));
    mnt.mnt_time = tbuf;

    return (0);
}

#define UNMOUNTTRIES 6
/*
 * umount_nfs - unmount a file system when finished
 */
int
umount_nfs(fsname, dir)
char *fsname, *dir;
{
    char *p;
    char *hostname;
    int s = -1;
    struct timeval timeout;
    CLIENT *client;
    enum clnt_stat rpc_stat;
    int count = 0;

    if (Debug)
        printf("umount: fsname %s dir %s\n", fsname, dir);
    /*
     * Give the filesystem time to become un-busy when unmounting.
     * If child aborted and is takes a core dump, we may receive the
     * SIGCHLD before the core dump is completed.
     */
    while (umount(dir) == -1) {
        if (errno != EBUSY) {
            perror(dir);
            return (1);
        }

        if (++count > UNMOUNTTRIES)
            return (1);
        sleep(10);
    }

    if (Debug)
        printf("umount_nfs: unmounting %s\n", dir);

    if ((p = strchr(fsname, ':')) == NULL)
        return (1);
    *p++ = 0;
    hostname = fsname;


    if ((client = clnt_create(hostname, MOUNTPROG, MOUNTVERS, "udp"))
        == NULL) {
        clnt_spcreateerror("Warning on umount create:");
        fprintf(stderr, "\n\r");
        return (1);
    }
    if (bindudp_resvport(client) < 0) {
        errprintf(NULL, "umount %s:%s:%s", hostname, p,
              "Could not bind to reserved port\n");
        clnt_destroy(client);
        return (1);
    }

/* #ifdef       NOWAWY
/*  client->cl_auth = authunix_create_default();
/* #endif   /*  NOWAY       */
/* */

    timeout.tv_usec = 0;
    timeout.tv_sec = 25;

    rpc_stat = clnt_call(client, MOUNTPROC_UMNT, xdr_dirpath, (caddr_t) &p,
                 xdr_void, (char *)NULL, timeout);

    clnt_destroy(client);

    if (rpc_stat != RPC_SUCCESS) {
        clnt_perror(client, "Warning: umount:");
        fprintf(stderr, "\n\r");
        return (1);
    }

    return (0);
}


static struct mnttab *
dupmnttab(mnt)
struct mnttab *mnt;
{
    struct mnttab *new;
    void freemnttab();

    new = (struct mnttab *)malloc(sizeof (*new));
    if (new == NULL)
        goto alloc_failed;
    memset((char *)new, 0, sizeof (*new));
    new->mnt_special = strdup(mnt->mnt_special);
    if (new->mnt_special == NULL)
        goto alloc_failed;
    new->mnt_mountp = strdup(mnt->mnt_mountp);
    if (new->mnt_mountp == NULL)
        goto alloc_failed;
    new->mnt_fstype = strdup(mnt->mnt_fstype);
    if (new->mnt_fstype == NULL)
        goto alloc_failed;
    if (mnt->mnt_mntopts != NULL)
        if ((new->mnt_mntopts = strdup(mnt->mnt_mntopts)) == NULL)
            goto alloc_failed;
    if (mnt->mnt_time != NULL)
        if ((new->mnt_time = strdup(mnt->mnt_time)) == NULL)
            goto alloc_failed;

    return (new);

      alloc_failed:
    errprintf(NULL, "dupmnttab: memory allocation failed\n");
    freemnttab(new);
    return (NULL);
}


/*
 * Free a single mnttab structure
 */
static void
freemnttab(mnt)
struct mnttab *mnt;
{
    if (mnt) {
        if (mnt->mnt_special)
            free(mnt->mnt_special);
        if (mnt->mnt_mountp)
            free(mnt->mnt_mountp);
        if (mnt->mnt_fstype)
            free(mnt->mnt_fstype);
        if (mnt->mnt_mntopts)
            free(mnt->mnt_mntopts);
        if (mnt->mnt_time)
            free(mnt->mnt_time);
        free(mnt);
    }
}


/* the following structure is used to build a list of */
/* mnttab structures from /etc/mnttab. */
struct mntlist {
    struct mnttab *mntl_mnt;
    struct mntlist *mntl_next;
};


/*
 * Free a list of mnttab structures
 */
static void
freemntlist(mntl)
struct mntlist *mntl;
{
    struct mntlist *mntl_tmp;

    while (mntl) {
        freemnttab(mntl->mntl_mnt);
        mntl_tmp = mntl;
        mntl = mntl->mntl_next;
        free(mntl_tmp);
    }
}


/*
 * parsefs - given a name of the form host:/path/name/for/file
 *  connect to the give host and look for the exported file system
 *  that matches.
 * Returns: pointer to string containing the part of the pathname
 *  within the exported directory.
 *  Returns NULL on errors.
 */
char *
parsefs(fullname, error)
char    *fullname;
char    *error;
{
    char    *dir,
    *subdir;
    struct exportnode   *ex = NULL;
    int err;
    int bestlen = 0;
    int len,
    dirlen;

    if (Debug && errno)
        printf("parsefs of %s entered with errno %d %s\n",
            fullname, errno, strerror(errno));

    dir = strchr(fullname, ':');
    if (dir == NULL) {

        errprintf(error, "No host name in %s\n", fullname);
        return (NULL);
    }
    *dir++ = '\0';

    if (Debug)
        printf("parsefs before rpc_call: ERRNO:%d\n", errno);

    if (err = rpc_call(fullname, MOUNTPROG, MOUNTVERS, MOUNTPROC_EXPORT,
            xdr_void, 0, xdr_exports, (char *)&ex, "udp")) {

        if (err == (int)RPC_TIMEDOUT)
            errprintf(error, "Host %s is not running mountd\n",
                fullname);
        else
            errprintf(error, "RPC error %d with host %s (%s)\n",
                err, fullname, clnt_sperrno(err));

        if (Debug && errno) {
            printf("parsefs: mount call to %s returned %d %s\n",
                fullname,
                err,
                clnt_sperrno(err));
            printf("with errno %d:\t%s\n",  errno, strerror(errno));
        }
        return (NULL);
    }

    if (Debug)
        printf("parsefs after rpc_call: ERRNO:%d\n", errno);

    dirlen = strlen(dir);

    if (Debug && errno) {
        printf("parsefs: mount call to %s returned %d %s\n",
            fullname,
            err,
            clnt_sperrno(err));
        printf("with errno %d:\t%s\n", errno, strerror(errno));
    }

    if (Debug)
        printf("parsefs: checking export list:\n");

    for (; ex; ex = ex->ex_next) {
        len = strlen(ex->ex_dir);
        if (len > bestlen && len <= dirlen &&
            strncmp(dir, ex->ex_dir, len) == 0 &&
            (dir[len] == '/' || dir[len] == '\0'))
            bestlen = len;

        if (Debug)
            printf("\t%d\t%s\n", bestlen, ex->ex_dir);
    }

    if (bestlen == 0) {
        errprintf(error, "%s not exported by %s\n",
            dir, fullname);
        return (NULL);
    }

    if (dir[bestlen] == '\0')
        subdir = &dir[bestlen];
    else {
        dir[bestlen] = '\0';
        subdir = &dir[bestlen+1];
    }
    *--dir = ':';

    return (subdir);
}


/*
 * Get the network address for the service identified by "prog"
 * and "vers" on "hostname".  The netconfig address is returned
 * in the value of "nconfp".
 * If the hostname is the same as the last call, then the same
 * transport is used as last time (same netconfig entry).
 */


static struct netbuf *
get_addr(hostname, prog, vers, nconfp)
char *hostname;
int prog, vers;
struct netconfig **nconfp;
{
    static char prevhost[MAXHOSTNAMELEN+1];
    static struct netconfig *nconf;
    static NCONF_HANDLE *nc = NULL;
    struct netbuf *nb = NULL;
    struct t_bind *tbind = NULL;
    struct netconfig *getnetconfig();
    struct netconfig *getnetconfigent();
    enum clnt_stat cs;
    struct timeval tv;
    int fd = -1;

    if (strcmp(hostname, prevhost) != 0) {
        if (nc)
            endnetconfig(nc);
        nc = setnetconfig();
        if (nc == NULL)
            goto done;
    retry:
        /*
         * If the port number is specified then UDP is needed.
         * Otherwise any connectionless transport will do.
         */
        while (nconf = getnetconfig(nc)) {
            if ((nconf->nc_flag & NC_VISIBLE) &&
                nconf->nc_semantics == NC_TPI_CLTS) {
                break;
            }
        }
        if (nconf == NULL)
            goto done;
        (void) strcpy(prevhost, hostname);
    }

    fd = t_open(nconf->nc_device, O_RDWR, NULL);
    if (fd < 0)
        goto done;

    tbind = (struct t_bind *) t_alloc(fd, T_BIND, T_ADDR);
    if (tbind == NULL)
        goto done;

    if (rpcb_getaddr(prog, vers, nconf, &tbind->addr, hostname) == 0) {
        t_free((char *) tbind, T_BIND);
        tbind = NULL;
        goto retry;
    }
    *nconfp = nconf;

    /*
     * Make a copy of the netbuf to return
     */
    nb = (struct netbuf *) malloc(sizeof (struct netbuf));
    if (nb == NULL) {
        errprintf(NULL, "no memory");
        goto done;
    }
    *nb = tbind->addr;
    nb->buf = (char *)malloc(nb->len);
    if (nb->buf == NULL) {
        errprintf(NULL, "no memory");
        free(nb);
        nb = NULL;
        goto done;
    }
    (void) memcpy(nb->buf, tbind->addr.buf, tbind->addr.len);

done:
    if (tbind)
        t_free((char *) tbind, T_BIND);
    if (fd >= 0)
        (void) t_close(fd);
    return (nb);
}

static struct knetconfig *
get_knconf(nconf)
struct netconfig *nconf;
{
    struct stat stbuf;
    struct knetconfig *k;

    if (stat(nconf->nc_device, &stbuf) < 0) {
        errprintf(NULL, "get_knconf: stat %s: %m", nconf->nc_device);
        return (NULL);
    }
    k = (struct knetconfig *) malloc(sizeof (*k));
    if (k == NULL)
        goto nomem;
    k->knc_semantics = nconf->nc_semantics;
    k->knc_protofmly = strdup(nconf->nc_protofmly);
    if (k->knc_protofmly == NULL)
        goto nomem;
    k->knc_proto = strdup(nconf->nc_proto);
    if (k->knc_proto == NULL)
        goto nomem;
    k->knc_rdev = stbuf.st_rdev;

    return (k);

nomem:
    errprintf(NULL, "get_knconf: no memory");
    free_knconf(k);
    return (NULL);
}

static void
free_knconf(k)
struct knetconfig *k;
{
    if (k == NULL)
        return;
    if (k->knc_protofmly)
        free(k->knc_protofmly);
    if (k->knc_proto)
        free(k->knc_proto);
    free(k);
}

static void
netbuf_free(nb)
struct netbuf *nb;
{
    if (nb == NULL)
        return;
    if (nb->buf)
        free(nb->buf);
    free(nb);
}


static enum clnt_stat
pingnfs(hostname, versp)
char *hostname;
rpcvers_t *versp;
{
    CLIENT *cl;
    enum clnt_stat clnt_stat;
    static char goodhost[MAXHOSTNAMELEN+1];
    static char deadhost[MAXHOSTNAMELEN+1];
    static time_t goodtime, deadtime;
    int cache_time = 60;    /* sec */

    if (goodtime > time_now && strcmp(hostname, goodhost) == 0)
        return (RPC_SUCCESS);
    if (deadtime > time_now && strcmp(hostname, deadhost) == 0)
        return (RPC_TIMEDOUT);

    if (Debug)
        printf("ping %s ", hostname);

    /* ping the NFS nullproc on the server */

    cl = clnt_create_vers(hostname, NFS_PROGRAM, versp, NFS_VERSMIN,
            NFS_VERSMAX, "udp");
    if (cl == NULL) {
        errprintf(NULL, "pingnfs: %s%s",
              hostname, clnt_spcreateerror(""));
        if (Debug)
            printf("clnt_create failed\n");
        clnt_stat = RPC_TIMEDOUT;
    } else {
        clnt_stat = RPC_SUCCESS;
        clnt_destroy(cl);
    }

    if (clnt_stat == RPC_SUCCESS) {
        (void) strcpy(goodhost, hostname);
        goodtime = time_now + cache_time;
    } else {
        (void) strcpy(deadhost, hostname);
        deadtime = time_now + cache_time;
    }

    if (Debug)
        (void) printf("%s\n", clnt_stat == RPC_SUCCESS ?
                "OK" : "NO RESPONSE");

    return (clnt_stat);
}

static int bindudp_resvport(client)
CLIENT *client;
{
    struct netconfig *udpnconf;
    int clfd;
    int rv;

    /* check for superuser as reserved ports are for superuser only */
    if (geteuid()) {
        errno = EACCES;
        return (-1);
    }

    if (clnt_control(client, CLGET_FD, (char *) &clfd) == FALSE) {
        errprintf(NULL, "Could not get file dscriptor for client handle\n");
        return (-1);
    }

    if (Debug)
        printf("Clnt_control success, clfd = %d\n", clfd);

    if (t_getstate(clfd) != T_UNBND) {
        if (t_unbind(clfd) < 0) {
            return (-1);
        }
    }

    if ((udpnconf = getnetconfigent("udp")) == (struct netconfig *) NULL) {
        errprintf(NULL, "no netconfig information about \"udp\"\n");
        return (-1);
    }

    if (Debug) {
        printf("getnetconfigent success\n");
    }

    if ((rv = netdir_options(udpnconf, ND_SET_RESERVEDPORT, clfd,
                (char *) NULL)) == -1) {
        if (Debug) {
            printf("netdir_options fails rv=%d\n", rv);
        }

        errprintf(NULL, netdir_sperror());
        return (-1);
    }

    if (Debug)
        printf("netdir_options success rv = %d\n", rv);

    freenetconfigent(udpnconf);
    return (0);
}