/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1989, 1993, 1995
 *      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/types.h>
#include <sys/queue.h>
#include <sys/file.h>
#include <sys/socket.h>
#include <sys/socketvar.h>

#include <err.h>
#include <getopt.h>
#include <netdb.h>
#include <rpc/rpc.h>
#include <rpc/pmap_clnt.h>
#include <rpc/pmap_prot.h>
#include <rpcsvc/mount.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <vis.h>

/* Constant defs */
#define ALL     1
#define DIRS    2

#define DODUMP                  0x1
#define DOEXPORTS               0x2
#define DOPARSABLEEXPORTS       0x4

struct mountlist {
        struct mountlist *ml_left;
        struct mountlist *ml_right;
        char    ml_host[MNTNAMLEN+1];
        char    ml_dirp[MNTPATHLEN+1];
};

struct grouplist {
        struct grouplist *gr_next;
        char    gr_name[MNTNAMLEN+1];
};

struct exportslist {
        struct exportslist *ex_next;
        struct grouplist *ex_groups;
        char    ex_dirp[MNTPATHLEN+1];
};

static struct mountlist *mntdump;
static struct exportslist *exportslist;
static int type = 0;

void print_dump(struct mountlist *);
static void usage(void) __dead2;
int xdr_mntdump(XDR *, struct mountlist **);
int xdr_exportslist(XDR *, struct exportslist **);
int tcp_callrpc(const char *host, int prognum, int versnum, int procnum,
                xdrproc_t inproc, char *in, xdrproc_t outproc, char *out);

static const struct option long_opts[] = {
        { "all",                        no_argument,    NULL,   'a' },
        { "directories",        no_argument,    NULL,   'd' },
        { "exports-script",     no_argument,    NULL,   'E' },
        { "exports",            no_argument,    NULL,   'e' },
        { NULL,                         0,                              NULL,   0 },
};

/*
 * This command queries the NFS mount daemon for it's mount list and/or
 * it's exports list and prints them out.
 * See "NFS: Network File System Protocol Specification, RFC1094, Appendix A"
 * and the "Network File System Protocol XXX.."
 * for detailed information on the protocol.
 */
int
main(int argc, char **argv)
{
        char strvised[MNTPATHLEN * 4 + 1];
        register struct exportslist *exp;
        register struct grouplist *grp;
        register int rpcs = 0, mntvers = 3;
        const char *host;
        int ch, estat, nbytes;

        while ((ch = getopt_long(argc, argv, "+adEe13", long_opts, NULL)) != -1)
                switch (ch) {
                case 'a':
                        if (type == 0) {
                                type = ALL;
                                rpcs |= DODUMP;
                        } else
                                usage();
                        break;
                case 'd':
                        if (type == 0) {
                                type = DIRS;
                                rpcs |= DODUMP;
                        } else
                                usage();
                        break;
                case 'E':
                        rpcs |= DOPARSABLEEXPORTS;
                        break;
                case 'e':
                        rpcs |= DOEXPORTS;
                        break;
                case '1':
                        mntvers = 1;
                        break;
                case '3':
                        mntvers = 3;
                        break;
                case '?':
                default:
                        usage();
                }
        argc -= optind;
        argv += optind;

        if ((rpcs & DOPARSABLEEXPORTS) != 0) {
                if ((rpcs & DOEXPORTS) != 0)
                        errx(1, "-E cannot be used with -e");
                if ((rpcs & DODUMP) != 0)
                        errx(1, "-E cannot be used with -a or -d");
        }

        if (argc > 0)
                host = *argv;
        else
                host = "localhost";

        if (rpcs == 0)
                rpcs = DODUMP;

        if (rpcs & DODUMP)
                if ((estat = tcp_callrpc(host, MOUNTPROG, mntvers,
                        MOUNTPROC_DUMP, (xdrproc_t)xdr_void, (char *)0,
                        (xdrproc_t)xdr_mntdump, (char *)&mntdump)) != 0) {
                        clnt_perrno(estat);
                        errx(1, "can't do mountdump rpc");
                }
        if (rpcs & (DOEXPORTS | DOPARSABLEEXPORTS))
                if ((estat = tcp_callrpc(host, MOUNTPROG, mntvers,
                        MOUNTPROC_EXPORT, (xdrproc_t)xdr_void, (char *)0,
                        (xdrproc_t)xdr_exportslist, (char *)&exportslist)) != 0) {
                        clnt_perrno(estat);
                        errx(1, "can't do exports rpc");
                }

        /* Now just print out the results */
        if (rpcs & DODUMP) {
                switch (type) {
                case ALL:
                        printf("All mount points on %s:\n", host);
                        break;
                case DIRS:
                        printf("Directories on %s:\n", host);
                        break;
                default:
                        printf("Hosts on %s:\n", host);
                        break;
                }
                print_dump(mntdump);
        }
        if (rpcs & DOEXPORTS) {
                printf("Exports list on %s:\n", host);
                exp = exportslist;
                while (exp) {
                        printf("%-34s ", exp->ex_dirp);
                        grp = exp->ex_groups;
                        if (grp == NULL) {
                                printf("Everyone\n");
                        } else {
                                while (grp) {
                                        printf("%s ", grp->gr_name);
                                        grp = grp->gr_next;
                                }
                                printf("\n");
                        }
                        exp = exp->ex_next;
                }
        }
        if (rpcs & DOPARSABLEEXPORTS) {
                exp = exportslist;
                while (exp) {
                        nbytes = strsnvis(strvised, sizeof(strvised),
                            exp->ex_dirp, VIS_GLOB | VIS_NL, "\"'$");
                        if (nbytes == -1)
                                err(1, "strsnvis");
                        printf("%s\n", strvised);
                        exp = exp->ex_next;
                }
        }
        exit(0);
}

/*
 * tcp_callrpc has the same interface as callrpc, but tries to
 * use tcp as transport method in order to handle large replies.
 */
int 
tcp_callrpc(const char *host, int prognum, int versnum, int procnum,
    xdrproc_t inproc, char *in, xdrproc_t outproc, char *out)
{
        CLIENT *client;
        struct timeval timeout;
        int rval;

        if ((client = clnt_create(host, prognum, versnum, "tcp")) == NULL &&
            (client = clnt_create(host, prognum, versnum, "udp")) == NULL)
                return ((int) rpc_createerr.cf_stat);

        timeout.tv_sec = 25;
        timeout.tv_usec = 0;
        rval = (int) clnt_call(client, procnum, 
                               inproc, in,
                               outproc, out,
                               timeout);
        clnt_destroy(client);
        return rval;
}

/*
 * Xdr routine for retrieving the mount dump list
 */
int
xdr_mntdump(XDR *xdrsp, struct mountlist **mlp)
{
        register struct mountlist *mp;
        register struct mountlist *tp;
        register struct mountlist **otp;
        int val, val2;
        int bool;
        char *strp;

        *mlp = (struct mountlist *)0;
        if (!xdr_bool(xdrsp, &bool))
                return (0);
        while (bool) {
                mp = (struct mountlist *)malloc(sizeof(struct mountlist));
                if (mp == NULL)
                        return (0);
                mp->ml_left = mp->ml_right = (struct mountlist *)0;
                strp = mp->ml_host;
                if (!xdr_string(xdrsp, &strp, MNTNAMLEN)) {
                        free(mp);
                        return (0);
                }
                strp = mp->ml_dirp;
                if (!xdr_string(xdrsp, &strp, MNTPATHLEN)) {
                        free(mp);
                        return (0);
                }

                /*
                 * Build a binary tree on sorted order of either host or dirp.
                 * Drop any duplications.
                 */
                if (*mlp == NULL) {
                        *mlp = mp;
                } else {
                        tp = *mlp;
                        while (tp) {
                                val = strcmp(mp->ml_host, tp->ml_host);
                                val2 = strcmp(mp->ml_dirp, tp->ml_dirp);
                                switch (type) {
                                case ALL:
                                        if (val == 0) {
                                                if (val2 == 0) {
                                                        free((caddr_t)mp);
                                                        goto next;
                                                }
                                                val = val2;
                                        }
                                        break;
                                case DIRS:
                                        if (val2 == 0) {
                                                free((caddr_t)mp);
                                                goto next;
                                        }
                                        val = val2;
                                        break;
                                default:
                                        if (val == 0) {
                                                free((caddr_t)mp);
                                                goto next;
                                        }
                                        break;
                                }
                                if (val < 0) {
                                        otp = &tp->ml_left;
                                        tp = tp->ml_left;
                                } else {
                                        otp = &tp->ml_right;
                                        tp = tp->ml_right;
                                }
                        }
                        *otp = mp;
                }
next:
                if (!xdr_bool(xdrsp, &bool))
                        return (0);
        }
        return (1);
}

/*
 * Xdr routine to retrieve exports list
 */
int
xdr_exportslist(XDR *xdrsp, struct exportslist **exp)
{
        register struct exportslist *ep;
        register struct grouplist *gp;
        int bool, grpbool;
        char *strp;

        *exp = (struct exportslist *)0;
        if (!xdr_bool(xdrsp, &bool))
                return (0);
        while (bool) {
                ep = (struct exportslist *)malloc(sizeof(struct exportslist));
                if (ep == NULL)
                        return (0);
                ep->ex_groups = (struct grouplist *)0;
                strp = ep->ex_dirp;
                if (!xdr_string(xdrsp, &strp, MNTPATHLEN))
                        return (0);
                if (!xdr_bool(xdrsp, &grpbool))
                        return (0);
                while (grpbool) {
                        gp = (struct grouplist *)malloc(sizeof(struct grouplist));
                        if (gp == NULL)
                                return (0);
                        strp = gp->gr_name;
                        if (!xdr_string(xdrsp, &strp, MNTNAMLEN))
                                return (0);
                        gp->gr_next = ep->ex_groups;
                        ep->ex_groups = gp;
                        if (!xdr_bool(xdrsp, &grpbool))
                                return (0);
                }
                ep->ex_next = *exp;
                *exp = ep;
                if (!xdr_bool(xdrsp, &bool))
                        return (0);
        }
        return (1);
}

static void
usage(void)
{
        fprintf(stderr, "usage: showmount [-a | -d] [-e3] [host]\n");
        exit(1);
}

/*
 * Print the binary tree in inorder so that output is sorted.
 */
void
print_dump(struct mountlist *mp)
{

        if (mp == NULL)
                return;
        if (mp->ml_left)
                print_dump(mp->ml_left);
        switch (type) {
        case ALL:
                printf("%s:%s\n", mp->ml_host, mp->ml_dirp);
                break;
        case DIRS:
                printf("%s\n", mp->ml_dirp);
                break;
        default:
                printf("%s\n", mp->ml_host);
                break;
        }
        if (mp->ml_right)
                print_dump(mp->ml_right);
}