/*      $NetBSD: umount.c,v 1.56 2025/07/01 20:11:13 kre Exp $  */

/*-
 * Copyright (c) 1980, 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1980, 1989, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)umount.c    8.8 (Berkeley) 5/8/95";
#else
__RCSID("$NetBSD: umount.c,v 1.56 2025/07/01 20:11:13 kre Exp $");
#endif
#endif /* not lint */

#include <sys/param.h>
#include <sys/stat.h>
#include <sys/mount.h>
#include <sys/time.h>
#ifndef SMALL
#include <sys/socket.h>

#include <netdb.h>
#include <rpc/rpc.h>
#include <rpc/pmap_clnt.h>
#include <rpc/pmap_prot.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsmount.h>

#include <dev/vndvar.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#endif /* !SMALL */

#include <err.h>
#include <errno.h>
#include <fstab.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <util.h>

typedef enum { MNTANY, MNTON, MNTFROM } mntwhat;

#ifndef SMALL
#include "mountprog.h"

static int       dflag, fake, verbose;
static char     *nfshost;
static struct addrinfo *nfshost_ai = NULL;

static int       namematch(const struct addrinfo *);
static int       sacmp(const struct sockaddr *, const struct sockaddr *);
static int       xdr_dir(XDR *, char *);
static const char *getmntproto(const char *);
static int       vn_detach(const char *);
#endif /* !SMALL */

static int       all, fflag;
static char     *getmntname(const char *, mntwhat, char **);
static int       umountfs(const char *, const char **, int);
static void      usage(void) __dead;

int
main(int argc, char *argv[])
{
        int ch, errs, raw = 0;
        char mntfromname[MAXPATHLEN];
#ifndef SMALL
        int mnts;
        struct statvfs *mntbuf;
        struct addrinfo hints;
#endif /* SMALL */
        const char **typelist = NULL;

#ifdef SMALL
#define OPTS "fR"
#else
#define OPTS "AadFfh:Rt:v"
#endif
        while ((ch = getopt(argc, argv, OPTS)) != -1)
                switch (ch) {
                case 'f':
                        fflag = MNT_FORCE;
                        break;
                case 'R':
                        raw = 1;
                        break;
#ifndef SMALL
                case 'A':
                case 'a':
                        all = 1;
                        break;
                case 'd':
                        dflag = 1;
                        break;
                case 'F':
                        fake = 1;
                        break;
                case 'h':       /* -h implies -A. */
                        all = 1;
                        nfshost = optarg;
                        break;
                case 't':
                        if (typelist != NULL)
                                errx(1, "only one -t option may be specified.");
                        typelist = makevfslist(optarg);
                        break;
                case 'v':
                        verbose++;
                        break;
#endif /* !SMALL */
                default:
                        usage();
                        /* NOTREACHED */
                }
        argc -= optind;
        argv += optind;

        if ((argc == 0 && !all) || (argc != 0 && all) || (all && raw))
                usage();

#ifndef SMALL
        /* -h implies "-t nfs" if no -t flag. */
        if ((nfshost != NULL) && (typelist == NULL))
                typelist = makevfslist("nfs");

        if (nfshost != NULL) {
                memset(&hints, 0, sizeof hints);
                if (getaddrinfo(nfshost, NULL, &hints, &nfshost_ai) != 0) {
                        nfshost_ai = NULL;
                }
        }
                
        errs = 0;
        if (all) {
                if ((mnts = getmntinfo(&mntbuf, ST_NOWAIT)) == 0) {
                        warn("getmntinfo");
                        errs = 1;
                }
                for (errs = 0, mnts--; mnts > 0; mnts--) {
                        if (checkvfsname(mntbuf[mnts].f_fstypename, typelist))
                                continue;
                        if (umountfs(mntbuf[mnts].f_mntonname, typelist,
                                     1) != 0)
                                errs = 1;
                }
        } else 
#endif /* !SMALL */
                for (errs = 0; *argv != NULL; ++argv) {
                        if (getfsspecname(mntfromname, sizeof(mntfromname),
                            *argv) == NULL)
                                err(EXIT_FAILURE, "%s", mntfromname);
                        if (umountfs(mntfromname, typelist, raw) != 0)
                                errs = 1;
                }
        return errs;
}

static int
umountfs(const char *name, const char **typelist, int raw)
{
#ifndef SMALL
        enum clnt_stat clnt_stat;
        struct timeval try;
        CLIENT *clp;
        char *hostp = NULL;
        struct addrinfo *ai = NULL, hints;
        const char *proto = NULL;
        struct statvfs sfs;
#endif /* !SMALL */
        const char *mntpt;
        char *type, rname[MAXPATHLEN], umountprog[MAXPATHLEN];
        mntwhat what;
        struct stat sb;

        if (raw) {
                mntpt = name;
        } else {

                what = MNTANY;
                if (realpath(name, rname) != NULL) {
                        name = rname;

                        if (stat(name, &sb) == 0) {
                                if (S_ISBLK(sb.st_mode))
                                        what = MNTON;
                                else if (S_ISDIR(sb.st_mode))
                                        what = MNTFROM;
                        }
                }
#ifdef SMALL
                else {
                        warn("%s", name);
                        return 1;
                }
#endif /* SMALL */
                mntpt = name;

                switch (what) {
                case MNTON:
                        if ((mntpt = getmntname(name, MNTON, &type)) == NULL) {
                                warnx("%s: not currently mounted", name);
                                return (1);
                        }
                        break;
                case MNTFROM:
                        if ((name = getmntname(mntpt, MNTFROM, &type)) == NULL) {
                                warnx("%s: not currently mounted", mntpt);
                                return (1);
                        }
                        break;
                default:
                        if ((name = getmntname(mntpt, MNTFROM, &type)) == NULL) {
                                name = mntpt;
                                if ((mntpt = getmntname(name, MNTON, &type)) == NULL) {
                                        warnx("%s: not currently mounted", name);
                                        return 1;
                                }
                        }
                }

#ifndef SMALL
                if (checkvfsname(type, typelist))
                        return 1;

                (void)memset(&hints, 0, sizeof hints);
                if (!strncmp(type, MOUNT_NFS,
                    sizeof(((struct statvfs *)NULL)->f_fstypename))) {
                        char *delimp;
                        proto = getmntproto(mntpt);
                        /* look for host:mountpoint */
                        if ((delimp = strrchr(name, ':')) != NULL) {
                                int len = delimp - name;
                                hostp = malloc(len + 1);
                                if (hostp == NULL)
                                        return 1;
                                memcpy(hostp, name, len);
                                hostp[len] = 0;
                                name += len + 1;
                                if (getaddrinfo(hostp, NULL, &hints, &ai) != 0)
                                        ai = NULL;
                        }
                }

                if (!namematch(ai))
                        return 1;
#endif /* ! SMALL */
                snprintf(umountprog, sizeof(umountprog), "umount_%s", type);
        }

#ifndef SMALL
        if (verbose) {
                (void)printf("%s: %sunmount from %s\n",
                    name, fake ? "fake " : "", mntpt);
                /* put this before the test of FAKE */ 
                if (!raw && verbose > 1) {
                        int OK = 1;
                        if (fake) {
                                OK = faccessat(AT_FDCWD, umountprog,
                                    X_OK, AT_EACCESS);
                        }
                        (void)printf("Trying unmount program %s%s\n",
                            umountprog,
                            (fake && OK < 0) ? ": would fail" : "");
                }
        }
        if (fake)
                return 0;
#endif /* ! SMALL */

        if (!raw) {
                /*
                 * The only options that need to be passed on are -f
                 * and -v.
                 */
                char *args[3];
                unsigned nargs = 0;

                args[nargs++] = umountprog;
                if (fflag == MNT_FORCE) {
                        args[nargs++] = __UNCONST("-f");
                }
#ifndef SMALL
                if (verbose) {
                        args[nargs++] = __UNCONST("-v");
                }
#endif
                execvp(umountprog, args);
                if (errno != ENOENT) {
                        warn("%s: execvp", umountprog);
                }
        }

#ifndef SMALL
        if (verbose > 1)
                (void)printf("(No separate unmount program.)\n");

        if (dflag && statvfs(mntpt, &sfs) == -1) {
                warn("%s: statvfs", mntpt);
                return 1;
        }
#endif

        if (unmount(mntpt, fflag) == -1) {
                warn("%s", mntpt);
                return 1;
        }

#ifndef SMALL
        if (ai != NULL && !(fflag & MNT_FORCE)) {
                clp = clnt_create(hostp, RPCPROG_MNT, RPCMNT_VER1, proto);
                if (clp  == NULL) {
                        clnt_pcreateerror("Cannot MNT PRC");
                        return 1;
                }
                clp->cl_auth = authsys_create_default();
                try.tv_sec = 20;
                try.tv_usec = 0;
                clnt_stat = clnt_call(clp, RPCMNT_UMOUNT, xdr_dir,
                    __UNCONST(name), xdr_void, NULL, try);
                if (clnt_stat != RPC_SUCCESS) {
                        clnt_perror(clp, "Bad MNT RPC");
                        return 1;
                }
                auth_destroy(clp->cl_auth);
                clnt_destroy(clp);
        }

        if (dflag) {
                if (vn_detach(sfs.f_mntfromname) == 0) {
                        if (verbose)
                                (void)printf("%s: detached\n",
                                    sfs.f_mntfromname);
                } else if (!all)
                        return (-1);
        }
#endif /* ! SMALL */
        return 0;
}

static char *
getmntname(const char *name, mntwhat what, char **type)
{
        static struct statvfs *mntbuf;
        static int mntsize;
        static char mntfromname[MAXPATHLEN];
        int i;

        if (mntbuf == NULL &&
            (mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0) {
                warn("getmntinfo");
                return (NULL);
        }
        for (i = mntsize - 1; i >= 0; i--) {
                if ((what == MNTON) && !strcmp(mntbuf[i].f_mntfromname, name)) {
                        if (type)
                                *type = mntbuf[i].f_fstypename;
                        return (mntbuf[i].f_mntonname);
                }
                if ((what == MNTFROM) && !strcmp(mntbuf[i].f_mntonname, name)) {
                        if (type)
                                *type = mntbuf[i].f_fstypename;
                        if (getfsspecname(mntfromname, sizeof(mntfromname),
                            mntbuf[i].f_mntfromname) == NULL)
                                err(EXIT_FAILURE, "%s", mntfromname);
                        return mntfromname;
                }
        }
        return (NULL);
}

#ifndef SMALL
static int
sacmp(const struct sockaddr *sa1, const struct sockaddr *sa2)
{
        const void *p1, *p2;
        size_t len;

        if (sa1->sa_family != sa2->sa_family)
                return 1;

        switch (sa1->sa_family) {
        case AF_INET:
                p1 = &((const struct sockaddr_in *)sa1)->sin_addr;
                p2 = &((const struct sockaddr_in *)sa2)->sin_addr;
                len = 4;
                break;
        case AF_INET6:
                p1 = &((const struct sockaddr_in6 *)sa1)->sin6_addr;
                p2 = &((const struct sockaddr_in6 *)sa2)->sin6_addr;
                len = 16;
                if (((const struct sockaddr_in6 *)sa1)->sin6_scope_id !=
                    ((const struct sockaddr_in6 *)sa2)->sin6_scope_id)
                        return 1;
                break;
        default:
                return 1;
        }

        return memcmp(p1, p2, len);
}

static int
namematch(const struct addrinfo *ai)
{
        struct addrinfo *aip;

        if (nfshost == NULL || nfshost_ai == NULL)
                return (1);

        while (ai != NULL) {
                aip = nfshost_ai;
                while (aip != NULL) {
                        if (sacmp(ai->ai_addr, aip->ai_addr) == 0)
                                return 1;
                        aip = aip->ai_next;
                }
                ai = ai->ai_next;
        }

        return 0;
}

/*
 * xdr routines for mount rpc's
 */
static int
xdr_dir(XDR *xdrsp, char *dirp)
{
        return xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN);
}

static const char *
getmntproto(const char *name)
{
        struct nfs_args nfsargs;
        struct sockaddr_storage ss;

        nfsargs.sotype = SOCK_DGRAM;
        nfsargs.addr = (struct sockaddr *)&ss; 
        nfsargs.addrlen = sizeof(ss);
        (void)mount("nfs", name, MNT_GETARGS, &nfsargs, sizeof(nfsargs));
        return nfsargs.sotype == SOCK_STREAM ? "tcp" : "udp";
}

int
vn_detach(const char *dev)
{
        struct vnd_ioctl vndio;
        char rdev[MAXPATHLEN + 1];
        int fd;

        if (strncmp(dev, "/dev/vnd", sizeof("/dev/vnd") - 1)) {
                if (!all)
                        warnx("invalid vnd device: %s", dev);
                return -1;
        }

        if ((fd = opendisk(dev, O_RDWR, rdev, sizeof(rdev), 0)) == -1) {
                warn("%s: opendisk", rdev);
                return -1;
        }

        memset(&vndio, 0, sizeof(vndio));
        vndio.vnd_flags = fflag ? VNDIOF_FORCE : 0;

        if (ioctl(fd, VNDIOCCLR, &vndio) == -1) {
                warn("%s: VNDIOCCLR", rdev);
                close(fd);
                return -1;
        }
        close(fd);

        return 0;
}
#endif /* !SMALL */

static void
usage(void)
{
#ifdef SMALL
        (void)fprintf(stderr,
            "Usage: %s [-fR]  special | node\n", getprogname());
#else
        (void)fprintf(stderr,
            "Usage: %s [-dfvFR] [-t fstypelist] special | node\n"
            "\t %s -a[dfvF] [-h host] [-t fstypelist]\n", getprogname(),
            getprogname());
#endif /* SMALL */
        exit(1);
}