/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1988 AT&T */
/*      All Rights Reserved */

#include <sys/utsname.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <rpc/types.h>
#include <rpc/auth.h>
#include <sys/t_lock.h>
#include <netdb.h>
#include "clnt.h"
#include <rpc/xdr.h>
#include <rpc/rpc_msg.h>
#include <rpc/rpc.h>
#include "brpc.h"
#include "auth_inet.h"
#include "pmap.h"
#include <rpcsvc/nfs_prot.h>
#include <rpcsvc/nfs4_prot.h>
#include "nfs_inet.h"
#include <rpcsvc/bootparam.h>
#include <dhcp_impl.h>
#include <rpcsvc/mount.h>
#include <sys/promif.h>
#include <sys/salib.h>
#include "socket_inet.h"
#include "ipv4.h"
#include "mac.h"
#include <sys/bootdebug.h>
#include <errno.h>
#include "dhcpv4.h"
#include <sys/mntent.h>

/* ARP timeout in milliseconds for BOOTP/RARP */
#define ARP_INETBOOT_TIMEOUT 1000

struct nfs_file         roothandle;                     /* root file handle */
static char             root_hostname[SYS_NMLN];        /* server hostname */
static char             my_hostname[MAXHOSTNAMELEN];
static char             root_pathbuf[NFS_MAXPATHLEN];   /* the root's path */
static char             root_boot_file[NFS_MAXPATHLEN]; /* optional boot file */
static struct sockaddr_in root_to;                      /* server sock ip */
                                                        /* in network order */
CLIENT                  *root_CLIENT = NULL;            /* CLIENT handle */
int dontroute = FALSE;  /* In case rarp/bootparams was selected */
char                    rootopts[MAX_PATH_LEN];
static gid_t            fake_gids = 1;  /* fake gids list for auth_unix */

extern void set_default_filename(char *);       /* boot.c */

/*
 * xdr routines used by mount.
 */

bool_t
xdr_fhstatus(XDR *xdrs, struct fhstatus *fhsp)
{
        if (!xdr_int(xdrs, (int *)&fhsp->fhs_status))
                return (FALSE);
        if (fhsp->fhs_status == 0) {
                return (xdr_fhandle(xdrs, fhsp->fhstatus_u.fhs_fhandle));
        }
        return (TRUE);
}

bool_t
xdr_fhandle(XDR *xdrs, fhandle fhp)
{
        return (xdr_opaque(xdrs, (char *)fhp, NFS_FHSIZE));
}

bool_t
xdr_path(XDR *xdrs, char **pathp)
{
        return (xdr_string(xdrs, pathp, MNTPATHLEN));
}

bool_t
xdr_fhandle3(XDR *xdrs, fhandle3 *objp)
{
        return (xdr_bytes(xdrs, (char **)&objp->fhandle3_val,
                                (uint_t *)&objp->fhandle3_len, FHSIZE3));
}

bool_t
xdr_mountstat3(XDR *xdrs, mountstat3 *objp)
{
        return (xdr_enum(xdrs, (enum_t *)objp));
}

bool_t
xdr_mountres3_ok(XDR *xdrs, mountres3_ok *objp)
{
        if (!xdr_fhandle3(xdrs, &objp->fhandle))
                return (FALSE);
        return (xdr_array(xdrs, (char **)&objp->auth_flavors.auth_flavors_val,
                        (uint_t *)&objp->auth_flavors.auth_flavors_len, ~0,
                        sizeof (int), (xdrproc_t)xdr_int));
}

bool_t
xdr_mountres3(XDR *xdrs, mountres3 *objp)
{
        if (!xdr_mountstat3(xdrs, &objp->fhs_status))
                return (FALSE);
        if (objp->fhs_status == MNT_OK)
                return (xdr_mountres3_ok(xdrs, &objp->mountres3_u.mountinfo));
        return (TRUE);
}

static int
nfsmountroot(char *path, struct nfs_file *filep)
{
        int             rexmit;
        int             resp_wait;
        enum clnt_stat  status;
        struct fhstatus root_tmp;                       /* to pass to rpc/xdr */

        /*
         * Wait up to 16 secs for first response, retransmitting expon.
         */
        rexmit = 0;     /* default retransmission interval */
        resp_wait = 16;

        do {
                status = brpc_call((rpcprog_t)MOUNTPROG, (rpcvers_t)MOUNTVERS,
                    (rpcproc_t)MOUNTPROC_MNT, xdr_path, (caddr_t)&path,
                    xdr_fhstatus, (caddr_t)&(root_tmp), rexmit, resp_wait,
                    &root_to, NULL, AUTH_UNIX);
                if (status == RPC_TIMEDOUT) {
                        dprintf("boot: %s:%s mount server not responding.\n",
                            root_hostname, path);
                }
                rexmit = resp_wait;
                resp_wait = 0;  /* use default wait time. */
        } while (status == RPC_TIMEDOUT);

        if ((status != RPC_SUCCESS) || (root_tmp.fhs_status != 0)) {
                nfs_error(root_tmp.fhs_status);
                root_to.sin_port = 0;
                return (-1);
        }

        /*
         * Since the mount succeeded, we'll mark the filep's
         * status as NFS_OK, and its type as NFDIR. If these
         * points aren't the case, then we wouldn't be here.
         */
        bcopy(&root_tmp.fhstatus_u.fhs_fhandle, &filep->fh.fh2, FHSIZE);
        filep->ftype.type2 = NFDIR;
        filep->version = NFS_VERSION;
        nfs_readsize = nfs_readsize <  NFS_MAXDATA ? nfs_readsize : NFS_MAXDATA;
        /*
         * Set a reasonable lower limit on readsize
         */
        nfs_readsize = (nfs_readsize != 0 && nfs_readsize < 512) ?
                                                        512 : nfs_readsize;
        return (0);
}

int
setup_root_vars(void)
{
        size_t          buflen;
        uint16_t        readsize;

        /*
         * Root server name. Required.
         */
        buflen = sizeof (root_hostname);
        if (dhcp_getinfo(DSYM_VENDOR, VS_NFSMNT_ROOTSRVR_NAME, 0,
            root_hostname, &buflen)) {
                root_hostname[buflen] = '\0';
        } else {
                dprintf("BOUND: Missing Root Server Name Option\n");
                errno = EINVAL;
                return (-1);
        }

        /*
         * Root server IP. Required.
         */
        buflen = sizeof (root_to.sin_addr);
        if (!dhcp_getinfo(DSYM_VENDOR, VS_NFSMNT_ROOTSRVR_IP, 0,
            &root_to.sin_addr, &buflen)) {
                dprintf("BOUND: Missing Root Server IP Option\n");
                errno = EINVAL;
                return (-1);
        }

        /*
         * Root path Required.
         */
        buflen = sizeof (root_pathbuf);
        if (dhcp_getinfo(DSYM_VENDOR, VS_NFSMNT_ROOTPATH, 0,
            root_pathbuf, &buflen)) {
                root_pathbuf[buflen] = '\0';
        } else {
                dprintf("BOUND: Missing Root Path Option\n");
                errno = EINVAL;
                return (-1);
        }

        /*
         * Optional Bootfile path.
         */
        buflen = sizeof (root_boot_file);
        if (dhcp_getinfo(DSYM_VENDOR, VS_NFSMNT_BOOTFILE, 0,
                    root_boot_file, &buflen)) {
                root_boot_file[buflen] = '\0';
                dprintf("BOUND: Optional Boot File is: %s\n", root_boot_file);
        }

        /* if we got a boot file name, use it as the default */
        if (root_boot_file[0] != '\0')
                set_default_filename(root_boot_file);

        /*
         * Set the NFS read size. The mount code will adjust it to
         * the maximum size.
         */
        buflen = sizeof (readsize);
        if (dhcp_getinfo(DSYM_VENDOR, VS_BOOT_NFS_READSIZE, 0,
            &readsize, &buflen)) {
                nfs_readsize = ntohs(readsize);
                if (boothowto & RB_VERBOSE) {
                        printf("Boot NFS read size: %d\n", nfs_readsize);
                }
        }

        /*
         * Optional rootopts.
         */
        buflen = sizeof (rootopts);
        if (dhcp_getinfo(DSYM_VENDOR, VS_NFSMNT_ROOTOPTS, 0,
            rootopts, &buflen)) {
                rootopts[buflen] = '\0';
                dprintf("BOUND: Optional Rootopts is: %s\n", rootopts);
        }

        return (0);
}

static void
mnt3_error(enum mountstat3 status)
{
        if (!(boothowto & RB_DEBUG))
                return;

        switch (status) {
        case MNT_OK:
                printf("Mount: No error.\n");
                break;
        case MNT3ERR_PERM:
                printf("Mount: Not owner.\n");
                break;
        case MNT3ERR_NOENT:
                printf("Mount: No such file or directory.\n");
                break;
        case MNT3ERR_IO:
                printf("Mount: I/O error.\n");
                break;
        case MNT3ERR_ACCES:
                printf("Mount: Permission denied.\n");
                break;
        case MNT3ERR_NOTDIR:
                printf("Mount: Not a directory.\n");
                break;
        case MNT3ERR_INVAL:
                printf("Mount: Invalid argument.\n");
                break;
        case MNT3ERR_NAMETOOLONG:
                printf("Mount: File name too long.\n");
                break;
        case MNT3ERR_NOTSUPP:
                printf("Mount: Operation not supported.\n");
                break;
        case MNT3ERR_SERVERFAULT:
                printf("Mount: Server fault.\n");
                break;
        default:
                printf("Mount: unknown error.\n");
                break;
        }
}

static int
nfs3mountroot(char *path, struct nfs_file *filep)
{
        int             rexmit;
        int             resp_wait;
        struct mountres3 res3;
        enum clnt_stat  status;

        /*
         * Wait up to 16 secs for first response, retransmitting expon.
         */
        rexmit = 0;     /* default retransmission interval */
        resp_wait = 16;

        /*
         * Try to mount using V3
         */
        do {
                bzero(&res3, sizeof (struct mountres3));

                status = brpc_call((rpcprog_t)MOUNTPROG, (rpcvers_t)MOUNTVERS3,
                    (rpcproc_t)MOUNTPROC_MNT, xdr_path, (caddr_t)&path,
                    xdr_mountres3, (caddr_t)&res3, rexmit, resp_wait,
                    &root_to, NULL, AUTH_UNIX);

                if (status != RPC_TIMEDOUT)
                        break;

                dprintf("boot: %s:%s mount server not responding.\n",
                            root_hostname, path);

                rexmit = resp_wait;
                resp_wait = 0;  /* use default wait time. */

                xdr_free(xdr_mountres3, (caddr_t)&res3);
        } while (status == RPC_TIMEDOUT);

        if ((status != RPC_SUCCESS) || (res3.fhs_status != MNT_OK)) {
                mnt3_error(res3.fhs_status);
                root_to.sin_port = 0;
                return (-1);
        }

        /*
         * Since the mount succeeded, we'll mark the filep's
         * status as NFS_OK, and its type as NF3DIR. If these
         * points aren't the case, then we wouldn't be here.
         */
        filep->fh.fh3.len = res3.mountres3_u.mountinfo.fhandle.fhandle3_len;
        bcopy(res3.mountres3_u.mountinfo.fhandle.fhandle3_val,
                        filep->fh.fh3.data,
                        filep->fh.fh3.len);
        filep->ftype.type3 = NF3DIR;
        filep->version = NFS_V3;
        /*
         * Hardwire in a known reasonable upper limit of 32K
         */
        nfs_readsize = nfs_readsize <  32 * 1024 ? nfs_readsize : 32 * 1024;
        /*
         * Set a reasonable lower limit on readsize
         */
        nfs_readsize = (nfs_readsize != 0 && nfs_readsize < 512) ?
                                                        512 : nfs_readsize;
        xdr_free(xdr_mountres3, (caddr_t)&res3);
        return (0);
}

/*
 * Setup v4 client for inetboot
 */
static int
nfs4init(char *path, uint16_t nfs_port)
{
        struct timeval  wait;
        int             fd = -1;
        int             error = 0;
        enum clnt_stat  rpc_stat;
        struct nfs_file rootpath;

        wait.tv_sec = RPC_RCVWAIT_MSEC / 1000;
        wait.tv_usec = 0;

        /*
         * If we haven't explicitly set the port number, set to the standard
         * 2049 and don't cause a rpcbind request.
         */
        if (nfs_port == 0)
                nfs_port = 2049;

        root_to.sin_port = htons(nfs_port);

        /*
         * Support TCP only
         */
        root_CLIENT = clntbtcp_create(&root_to, NFS_PROGRAM,
                                        NFS_V4, wait, &fd,
                                        NFS4BUF_SIZE, NFS4BUF_SIZE);

        if (root_CLIENT == NULL) {
                root_to.sin_port = 0;
                return (-1);
        }

        root_CLIENT->cl_auth =
                        authunix_create(my_hostname, 0, 1, 1, &fake_gids);

        /*
         * Send NULL proc the server first to see if V4 exists
         */
        rpc_stat = CLNT_CALL(root_CLIENT, NFSPROC4_NULL, xdr_void, NULL,
                                xdr_void, NULL, wait);

        if (rpc_stat != RPC_SUCCESS) {
                dprintf("boot: NULL proc failed NFSv4 service not available\n");
                AUTH_DESTROY(root_CLIENT->cl_auth);
                CLNT_DESTROY(root_CLIENT);
                root_to.sin_port = 0;
                return (-1);
        }

        /*
         * Do a lookup to get to the root_path.  This is nice since it can
         * handle multicomponent lookups.
         */
        roothandle.version = NFS_V4;
        roothandle.ftype.type4 = NF4DIR;
        roothandle.fh.fh4.len = 0;              /* Force a PUTROOTFH */
        roothandle.offset = (uint_t)0;          /* it's a directory! */
        error = lookup(path, &rootpath, TRUE);

        if (error) {
                printf("boot: lookup %s failed\n", path);
                return (-1);
        }
        roothandle = rootpath;  /* structure copy */

        /*
         * Hardwire in a known reasonable upper limit of 32K
         */
        nfs_readsize = nfs_readsize <  32 * 1024 ? nfs_readsize : 32 * 1024;
        /*
         * Set a reasonable lower limit on readsize
         */
        nfs_readsize = (nfs_readsize != 0 && nfs_readsize < 512) ?
                                                        512 : nfs_readsize;

        return (0);
}

static int
atoi(const char *p)
{
        int n;
        int c, neg = 0;

        if (!isdigit(c = *p)) {
                while (c == ' ' || c == '\t' || c == '\n')
                        c = *++p;
                switch (c) {
                case '-':
                        neg++;
                        /* FALLTHROUGH */
                case '+':
                        c = *++p;
                }
                if (!isdigit(c))
                        return (0);
        }
        for (n = '0' - c; isdigit(c = *++p); ) {
                n *= 10; /* two steps to avoid unnecessary overflow */
                n += '0' - c; /* accum neg to avoid surprises at MAX */
        }
        return (neg ? n : -n);
}

/*
 * Parse suboptions from a string.
 * Same as getsubopt(3C).
 */
static int
getsubopt(char **optionsp, char * const *tokens, char **valuep)
{
        char *s = *optionsp, *p;
        int i;
        size_t optlen;

        *valuep = NULL;
        if (*s == '\0')
                return (-1);
        p = strchr(s, ',');             /* find next option */
        if (p == NULL) {
                p = s + strlen(s);
        } else {
                *p++ = '\0';            /* mark end and point to next */
        }
        *optionsp = p;                  /* point to next option */
        p = strchr(s, '=');             /* find value */
        if (p == NULL) {
                optlen = strlen(s);
                *valuep = NULL;
        } else {
                optlen = p - s;
                *valuep = ++p;
        }
        for (i = 0; tokens[i] != NULL; i++) {
                if ((optlen == strlen(tokens[i])) &&
                    (strncmp(s, tokens[i], optlen) == 0))
                        return (i);
        }
        /* no match, point value at option and return error */
        *valuep = s;
        return (-1);
}

/*
 * The only interesting NFS mount options for initiating the kernel
 * all others are ignored.
 */
static char *optlist[] = {
#define OPT_RSIZE       0
        MNTOPT_RSIZE,
#define OPT_TIMEO       1
        MNTOPT_TIMEO,
#define OPT_VERS        2
        MNTOPT_VERS,
#define OPT_PROTO       3
        MNTOPT_PROTO,
#define OPT_PORT        4
        MNTOPT_PORT,
        NULL
};

/*
 * This routine will open a device as it is known by the V2 OBP. It
 * then goes thru the stuff necessary to initialize the network device,
 * get our network parameters, (using DHCP or rarp/bootparams), and
 * finally actually go and get the root filehandle. Sound like fun?
 * Suuurrrree. Take a look.
 *
 * Returns 0 if things worked. -1 if we crashed and burned.
 */
int
boot_nfs_mountroot(char *str)
{
        int             status;
        enum clnt_stat  rpc_stat;
        char            *root_path = &root_pathbuf[0];  /* to make XDR happy */
        struct timeval  wait;
        int             fd;
        int             bufsize;
        char            *opts, *val;
        int             nfs_version = 0;
        int             istcp = 1;
        int             nfs_port = 0;   /* Cause pmap to get port */
        struct sockaddr_in tmp_addr;    /* throw away */

        if (root_CLIENT != NULL) {
                AUTH_DESTROY(root_CLIENT->cl_auth);
                CLNT_DESTROY(root_CLIENT);
                root_CLIENT = NULL;
        }

        root_to.sin_family = AF_INET;
        root_to.sin_addr.s_addr = htonl(INADDR_ANY);
        root_to.sin_port = htons(0);

        mac_init(str);

        (void) ipv4_setpromiscuous(TRUE);

        if (get_netconfig_strategy() == NCT_BOOTP_DHCP) {
                if (boothowto & RB_VERBOSE)
                        printf("Using BOOTP/DHCP...\n");
                if (dhcp() != 0 || setup_root_vars() != 0) {
                        (void) ipv4_setpromiscuous(FALSE);
                        if (boothowto & RB_VERBOSE)
                                printf("BOOTP/DHCP configuration failed!\n");
                        return (-1);
                }

                /* now that we have an IP address, turn off promiscuous mode */
                (void) ipv4_setpromiscuous(FALSE);
        } else {
                /* Use RARP/BOOTPARAMS. RARP will try forever... */
                if (boothowto & RB_VERBOSE)
                        printf("Using RARP/BOOTPARAMS...\n");
                mac_call_rarp();

                /*
                 * Since there is no way to determine our netmask, and therefore
                 * figure out if the router we got is useful, we assume all
                 * services are local. Use DHCP if this bothers you.
                 */
                dontroute = TRUE;
                /*
                 * We are trying to keep the ARP response
                 * timeout on the lower side with BOOTP/RARP.
                 * We are doing this for BOOTP/RARP where policy
                 * doesn't allow to route the packets outside
                 * the subnet as it has no idea about the
                 * netmask. By doing so, we are reducing
                 * ARP response timeout for any packet destined
                 * for outside booting clients subnet. Client can
                 * not expect such ARP replies and will finally
                 * timeout after a long delay. This would cause
                 * booting client to get stalled for a longer
                 * time. We can not avoid accepting any outside
                 * subnet packets accidentally destined for the
                 * booting client.
                 */
                mac_set_arp_timeout(ARP_INETBOOT_TIMEOUT);

                /* now that we have an IP address, turn off promiscuous mode */
                (void) ipv4_setpromiscuous(FALSE);

                /* get our hostname */
                if (whoami() == FALSE)
                        return (-1);

                /* get our bootparams. */
                if (getfile("root", root_hostname, &root_to.sin_addr,
                    root_pathbuf) == FALSE)
                        return (-1);

                /* get our rootopts. */
                (void) getfile("rootopts", root_hostname, &tmp_addr.sin_addr,
                    rootopts);
        }

        /* mount root */
        if (boothowto & RB_VERBOSE) {
                printf("root server: %s (%s)\n", root_hostname,
                    inet_ntoa(root_to.sin_addr));
                printf("root directory: %s\n", root_pathbuf);
        }

        /*
         * Assumes we've configured the stack and thus know our
         * IP address/hostname, either by using DHCP or rarp/bootparams.
         */
        (void) gethostname(my_hostname, sizeof (my_hostname));

        wait.tv_sec = RPC_RCVWAIT_MSEC / 1000;
        wait.tv_usec = 0;

        /*
         * Parse out the interesting root options, if an invalid
         * or unknown option is provided, silently ignore it and
         * use the defaults.
         */
        opts = rootopts;
        while (*opts) {
                int ival;
                switch (getsubopt(&opts, optlist, &val)) {
                case OPT_RSIZE:
                        if (val == NULL || !isdigit(*val))
                                break;
                        nfs_readsize = atoi(val);
                        break;
                case OPT_TIMEO:
                        if (val == NULL || !isdigit(*val))
                                break;
                        ival = atoi(val);
                        wait.tv_sec = ival / 10;
                        wait.tv_usec = (ival % 10) * 100000;
                        break;
                case OPT_VERS:
                        if (val == NULL || !isdigit(*val))
                                break;
                        nfs_version = atoi(val);
                        break;
                case OPT_PROTO:
                        if (val == NULL || isdigit(*val))
                                break;
                        if ((strncmp(val, "udp", 3) == 0))
                                istcp = 0;
                        else
                                istcp = 1;      /* must be tcp */
                        break;
                case OPT_PORT:
                        if (val == NULL || !isdigit(*val))
                                break;
                        nfs_port = atoi(val);

                        /*
                         * Currently nfs_dlinet.c doesn't support setting
                         * the root NFS port. Delete this when it does.
                         */
                        nfs_port = 0;
                        break;
                default:
                        /*
                         * Unknown options are silently ignored
                         */
                        break;
                }
        }

        /*
         * If version is set, then try that version first.
         */
        switch (nfs_version) {
        case NFS_VERSION:
                if (nfsmountroot(root_path, &roothandle) == 0)
                        goto domount;
                break;
        case NFS_V3:
                if (nfs3mountroot(root_path, &roothandle) == 0)
                        goto domount;
                break;
        case NFS_V4:
                /*
                 * With v4 we skip the mount and go straight to
                 * setting the root filehandle.  Because of this we
                 * do things slightly differently and obtain our
                 * client handle first.
                 */
                if (istcp && nfs4init(root_path, nfs_port) == 0) {
                        /*
                         * If v4 init succeeded then we are done.  Just return.
                         */
                        return (0);
                }
        }

        /*
         * If there was no chosen version or the chosen version failed
         * try all versions in order, this may still fail to boot
         * at the kernel level if the options are not right, but be
         * generous at this early stage.
         */
        if (istcp && nfs4init(root_path, nfs_port) == 0) {
                /*
                 * If v4 init succeeded then we are done.  Just return.
                 */
                return (0);
        }

        if (nfs3mountroot(root_path, &roothandle) == 0)
                goto domount;

        if ((status = nfsmountroot(root_path, &roothandle)) != 0)
                return (status);

domount:
        /*
         * Only v2 and v3 go on from here.
         */
        roothandle.offset = (uint_t)0;          /* it's a directory! */
        root_to.sin_port = htons(nfs_port);     /* NFS is next after mount */

        /*
         * Create the CLIENT handle for NFS operations
         */
        if (roothandle.version == NFS_VERSION)
                bufsize = NFSBUF_SIZE;
        else
                bufsize = NFS3BUF_SIZE;

        /*
         * First try TCP then UDP (unless UDP asked for explicitly), if mountd
         * alows this version but neither transport is available we are stuck.
         */
        if (istcp) {
                fd = -1;
                root_CLIENT = clntbtcp_create(&root_to, NFS_PROGRAM,
                        roothandle.version, wait, &fd, bufsize, bufsize);
                if (root_CLIENT != NULL) {
                        root_CLIENT->cl_auth =
                            authunix_create(my_hostname, 0, 1, 1, &fake_gids);
                        /*
                         * Send NULL proc, check if the server really exists
                         */
                        rpc_stat = CLNT_CALL(root_CLIENT, 0,
                                        xdr_void, NULL, xdr_void, NULL, wait);

                        if (rpc_stat == RPC_SUCCESS)
                                return (0);

                        AUTH_DESTROY(root_CLIENT->cl_auth);
                        CLNT_DESTROY(root_CLIENT);
                        root_CLIENT = NULL;
                }
                /* Fall through to UDP case */
        }

        fd = -1;
        root_CLIENT = clntbudp_bufcreate(&root_to, NFS_PROGRAM,
                        roothandle.version, wait, &fd, bufsize, bufsize);
        if (root_CLIENT == NULL)
                return (-1);

        root_CLIENT->cl_auth =
                            authunix_create(my_hostname, 0, 1, 1, &fake_gids);
        /*
         * Send NULL proc, check if the server really exists
         */
        rpc_stat = CLNT_CALL(root_CLIENT, 0,
                                xdr_void, NULL, xdr_void, NULL, wait);

        if (rpc_stat == RPC_SUCCESS)
                return (0);

        AUTH_DESTROY(root_CLIENT->cl_auth);
        CLNT_DESTROY(root_CLIENT);
        root_CLIENT = NULL;
        return (-1);
}