freebsd-dev/sbin/umount/umount.c
2000-09-07 07:03:11 +00:00

695 lines
18 KiB
C

/*-
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1980, 1989, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)umount.c 8.8 (Berkeley) 5/8/95";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/mount.h>
#include <netdb.h>
#include <rpc/rpc.h>
#include <nfs/rpcv2.h>
#include <err.h>
#include <fstab.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "mounttab.h"
#define ISDOT(x) ((x)[0] == '.' && (x)[1] == '\0')
#define ISDOTDOT(x) ((x)[0] == '.' && (x)[1] == '.' && (x)[2] == '\0')
typedef enum { MNTON, MNTFROM, NOTHING } mntwhat;
typedef enum { MARK, UNMARK, NAME, COUNT, FREE } dowhat;
struct mtablist *mtabhead;
int fflag, vflag;
char *nfshost;
void checkmntlist (char *, char **, char **, char **);
int checkvfsname (const char *, char **);
char *getmntname (const char *, const char *,
mntwhat, char **, dowhat);
char *getrealname(char *, char *resolved_path);
char **makevfslist (const char *);
size_t mntinfo (struct statfs **);
int namematch (struct hostent *);
int umountall (char **);
int umountfs (char *, char **);
void usage (void);
int xdr_dir (XDR *, char *);
int
main(int argc, char *argv[])
{
int all, errs, ch, mntsize;
char **typelist = NULL, *mntonname, *mntfromname;
char *type, *mntfromnamerev, *mntonnamerev;
struct statfs *mntbuf;
/* Start disks transferring immediately. */
sync();
all = errs = 0;
while ((ch = getopt(argc, argv, "Aafh:t:v")) != -1)
switch (ch) {
case 'A':
all = 2;
break;
case 'a':
all = 1;
break;
case 'f':
fflag = MNT_FORCE;
break;
case 'h': /* -h implies -A. */
all = 2;
nfshost = optarg;
break;
case 't':
if (typelist != NULL)
err(1, "only one -t option may be specified");
typelist = makevfslist(optarg);
break;
case 'v':
vflag = 1;
break;
default:
usage();
/* NOTREACHED */
}
argc -= optind;
argv += optind;
if ((argc == 0 && !all) || (argc != 0 && all))
usage();
/* -h implies "-t nfs" if no -t flag. */
if ((nfshost != NULL) && (typelist == NULL))
typelist = makevfslist("nfs");
switch (all) {
case 2:
if ((mntsize = mntinfo(&mntbuf)) <= 0)
break;
/*
* We unmount the nfs-mounts in the reverse order
* that they were mounted.
*/
for (errs = 0, mntsize--; mntsize > 0; mntsize--) {
if (checkvfsname(mntbuf[mntsize].f_fstypename,
typelist))
continue;
/*
* Check if a mountpoint is laid over by another mount.
* A warning will be printed to stderr if this is
* the case. The laid over mount remains unmounted.
*/
mntonname = mntbuf[mntsize].f_mntonname;
mntfromname = mntbuf[mntsize].f_mntfromname;
mntonnamerev = getmntname(getmntname(mntonname,
NULL, MNTFROM, &type, NAME), NULL,
MNTON, &type, NAME);
mntfromnamerev = getmntname(mntonnamerev,
NULL, MNTFROM, &type, NAME);
if (strcmp(mntonnamerev, mntonname) == 0 &&
strcmp(mntfromnamerev, mntfromname ) != 0)
warnx("cannot umount %s, %s\n "
"is mounted there, umount it first",
mntonname, mntfromnamerev);
if (umountfs(mntbuf[mntsize].f_mntonname,
typelist) != 0)
errs = 1;
}
free(mntbuf);
break;
case 1:
if (setfsent() == 0)
err(1, "%s", _PATH_FSTAB);
errs = umountall(typelist);
break;
case 0:
for (errs = 0; *argv != NULL; ++argv)
if (umountfs(*argv, typelist) != 0)
errs = 1;
break;
}
(void)getmntname(NULL, NULL, NOTHING, NULL, FREE);
exit(errs);
}
int
umountall(char **typelist)
{
struct vfsconf vfc;
struct fstab *fs;
int rval;
char *cp;
static int firstcall = 1;
if ((fs = getfsent()) != NULL)
firstcall = 0;
else if (firstcall)
errx(1, "fstab reading failure");
else
return (0);
do {
/* Ignore the root. */
if (strcmp(fs->fs_file, "/") == 0)
continue;
/*
* !!!
* Historic practice: ignore unknown FSTAB_* fields.
*/
if (strcmp(fs->fs_type, FSTAB_RW) &&
strcmp(fs->fs_type, FSTAB_RO) &&
strcmp(fs->fs_type, FSTAB_RQ))
continue;
/* Ignore unknown file system types. */
if (getvfsbyname(fs->fs_vfstype, &vfc) == -1)
continue;
if (checkvfsname(fs->fs_vfstype, typelist))
continue;
/*
* We want to unmount the file systems in the reverse order
* that they were mounted. So, we save off the file name
* in some allocated memory, and then call recursively.
*/
if ((cp = malloc((size_t)strlen(fs->fs_file) + 1)) == NULL)
err(1, "malloc failed");
(void)strcpy(cp, fs->fs_file);
rval = umountall(typelist);
rval = umountfs(cp, typelist) || rval;
free(cp);
return (rval);
} while ((fs = getfsent()) != NULL);
return (0);
}
int
umountfs(char *name, char **typelist)
{
enum clnt_stat clnt_stat;
struct hostent *hp;
struct mtablist *mtab;
struct sockaddr_in saddr;
struct timeval pertry, try;
CLIENT *clp;
size_t len;
int so, speclen, do_rpc;
char *mntonname, *mntfromname;
char *mntfromnamerev;
char *nfsdirname, *orignfsdirname;
char *resolved, realname[MAXPATHLEN];
char *type, *delimp, *hostp, *origname;
len = 0;
mtab = NULL;
mntfromname = mntonname = delimp = hostp = orignfsdirname = NULL;
/*
* 1. Check if the name exists in the mounttable.
*/
(void)checkmntlist(name, &mntfromname, &mntonname, &type);
/*
* 2. Remove trailing slashes if there are any. After that
* we look up the name in the mounttable again.
*/
if (mntfromname == NULL && mntonname == NULL) {
speclen = strlen(name);
for (speclen = strlen(name);
speclen > 1 && name[speclen - 1] == '/';
speclen--)
name[speclen - 1] = '\0';
(void)checkmntlist(name, &mntfromname, &mntonname, &type);
resolved = name;
/* Save off original name in origname */
if ((origname = strdup(name)) == NULL)
err(1, "strdup");
/*
* 3. Check if the deprecated nfs-syntax with an '@'
* has been used and translate it to the ':' syntax.
* Look up the name in the mounttable again.
*/
if (mntfromname == NULL && mntonname == NULL) {
if ((delimp = strrchr(name, '@')) != NULL) {
hostp = delimp + 1;
if (*hostp != '\0') {
/*
* Make both '@' and ':'
* notations equal
*/
char *host = strdup(hostp);
len = strlen(hostp);
if (host == NULL)
err(1, "strdup");
memmove(name + len + 1, name,
(size_t)(delimp - name));
name[len] = ':';
memmove(name, host, len);
free(host);
}
for (speclen = strlen(name);
speclen > 1 && name[speclen - 1] == '/';
speclen--)
name[speclen - 1] = '\0';
name[len + speclen + 1] = '\0';
(void)checkmntlist(name, &mntfromname,
&mntonname, &type);
resolved = name;
}
/*
* 4. Check if a relative mountpoint has been
* specified. This should happen as last check,
* the order is important. To prevent possible
* nfs-hangs, we just call realpath(3) on the
* basedir of mountpoint and add the dirname again.
* Check the name in mounttable one last time.
*/
if (mntfromname == NULL && mntonname == NULL) {
(void)strcpy(name, origname);
if ((getrealname(name, realname)) != NULL) {
(void)checkmntlist(realname,
&mntfromname, &mntonname, &type);
resolved = realname;
}
/*
* All tests failed, return to main()
*/
if (mntfromname == NULL && mntonname == NULL) {
(void)strcpy(name, origname);
warnx("%s: not currently mounted",
origname);
free(origname);
return (1);
}
}
}
free(origname);
} else
resolved = name;
if (checkvfsname(type, typelist))
return (1);
hp = NULL;
nfsdirname = NULL;
if (!strcmp(type, "nfs")) {
if ((nfsdirname = strdup(mntfromname)) == NULL)
err(1, "strdup");
orignfsdirname = nfsdirname;
if ((delimp = strchr(nfsdirname, ':')) != NULL) {
*delimp = '\0';
hostp = nfsdirname;
if ((hp = gethostbyname(hostp)) == NULL) {
warnx("can't get net id for host");
}
nfsdirname = delimp + 1;
}
}
/*
* Check if the reverse entrys of the mounttable are really the
* same as the normal ones.
*/
if ((mntfromnamerev = strdup(getmntname(getmntname(mntfromname,
NULL, MNTON, &type, NAME), NULL, MNTFROM, &type, NAME))) == NULL)
err(1, "strdup");
/*
* Mark the uppermost mount as unmounted.
*/
(void)getmntname(mntfromname, mntonname, NOTHING, &type, MARK);
/*
* If several equal mounts are in the mounttable, check the order
* and warn the user if necessary.
*/
if (strcmp(mntfromnamerev, mntfromname ) != 0 &&
strcmp(resolved, mntonname) != 0) {
warnx("cannot umount %s, %s\n "
"is mounted there, umount it first",
mntonname, mntfromnamerev);
/* call getmntname again to set mntcheck[i] to 0 */
(void)getmntname(mntfromname, mntonname,
NOTHING, &type, UNMARK);
return (1);
}
free(mntfromnamerev);
/*
* Check if we have to start the rpc-call later.
* If there are still identical nfs-names mounted,
* we skip the rpc-call. Obviously this has to
* happen before unmount(2), but it should happen
* after the previous namecheck.
*/
if (strcmp(type, "nfs") == 0 && getmntname(mntfromname, NULL, NOTHING,
&type, COUNT) != NULL)
do_rpc = 1;
else
do_rpc = 0;
if (!namematch(hp))
return (1);
if (unmount(mntonname, fflag) != 0 ) {
warn("unmount of %s failed", mntonname);
return (1);
}
if (vflag)
(void)printf("%s: unmount from %s\n", mntfromname, mntonname);
/*
* Report to mountd-server which nfsname
* has been unmounted.
*/
if (hp != NULL && !(fflag & MNT_FORCE) && do_rpc) {
memset(&saddr, 0, sizeof(saddr));
saddr.sin_family = AF_INET;
saddr.sin_port = 0;
memmove(&saddr.sin_addr, hp->h_addr,
MIN(hp->h_length, sizeof(saddr.sin_addr)));
pertry.tv_sec = 3;
pertry.tv_usec = 0;
so = RPC_ANYSOCK;
if ((clp = clntudp_create(&saddr,
RPCPROG_MNT, RPCMNT_VER1, pertry, &so)) == NULL) {
clnt_pcreateerror("Cannot MNT PRC");
return (1);
}
clp->cl_auth = authunix_create_default();
try.tv_sec = 20;
try.tv_usec = 0;
clnt_stat = clnt_call(clp, RPCMNT_UMOUNT, xdr_dir,
nfsdirname, xdr_void, (caddr_t)0, try);
if (clnt_stat != RPC_SUCCESS) {
clnt_perror(clp, "Bad MNT RPC");
return (1);
}
/*
* Remove the unmounted entry from /var/db/mounttab.
*/
if (read_mtab(mtab)) {
mtab = mtabhead;
clean_mtab(hostp, nfsdirname);
if(!write_mtab())
warnx("cannot remove entry %s:%s",
hostp, nfsdirname);
free_mtab();
}
free(orignfsdirname);
auth_destroy(clp->cl_auth);
clnt_destroy(clp);
}
return (0);
}
char *
getmntname(const char *fromname, const char *onname,
mntwhat what, char **type, dowhat mark)
{
static struct statfs *mntbuf;
static size_t mntsize = 0;
static char *mntcheck = NULL;
static char *mntcount = NULL;
int i, count;
if (mntsize <= 0) {
if ((mntsize = mntinfo(&mntbuf)) <= 0)
return (NULL);
}
if (mntcheck == NULL) {
if ((mntcheck = calloc(mntsize + 1, sizeof(int))) == NULL ||
(mntcount = calloc(mntsize + 1, sizeof(int))) == NULL)
err(1, "calloc");
}
/*
* We want to get the file systems in the reverse order
* that they were mounted. Mounted and unmounted filesystems
* are marked or unmarked in a table called 'mntcheck'.
* Unmount(const char *dir, int flags) does only take the
* mountpoint as argument, not the destination. If we don't pay
* attention to the order, it can happen that a overlaying
* filesystem get's unmounted instead of the one the user
* has choosen.
*/
switch (mark) {
case NAME:
/* Return only the specific name */
for (i = mntsize - 1; i >= 0; i--) {
if (fromname != NULL && what == MNTON &&
!strcmp(mntbuf[i].f_mntfromname, fromname) &&
mntcheck[i] != 1) {
if (type)
*type = mntbuf[i].f_fstypename;
return (mntbuf[i].f_mntonname);
}
if (fromname != NULL && what == MNTFROM &&
!strcmp(mntbuf[i].f_mntonname, fromname) &&
mntcheck[i] != 1) {
if (type)
*type = mntbuf[i].f_fstypename;
return (mntbuf[i].f_mntfromname);
}
}
return (NULL);
case MARK:
/* Mark current mount with '1' and return name */
for (i = mntsize - 1; i >= 0; i--) {
if (mntcheck[i] == 0 &&
(strcmp(mntbuf[i].f_mntonname, onname) == 0) &&
(strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) {
mntcheck[i] = 1;
return (mntbuf[i].f_mntonname);
}
}
return (NULL);
case UNMARK:
/* Unmark current mount with '0' and return name */
for (i = 0; i < mntsize; i++) {
if (mntcheck[i] == 1 &&
(strcmp(mntbuf[i].f_mntonname, onname) == 0) &&
(strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) {
mntcheck[i] = 0;
return (mntbuf[i].f_mntonname);
}
}
return (NULL);
case COUNT:
/* Count the equal mntfromnames */
count = 0;
for (i = mntsize - 1; i >= 0; i--) {
if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)
count++;
}
/* Mark the already unmounted mounts and return
* mntfromname if count <= 1. Else return NULL.
*/
for (i = mntsize - 1; i >= 0; i--) {
if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0) {
if (mntcount[i] == 1)
count--;
else {
mntcount[i] = 1;
break;
}
}
}
if (count <= 1)
return (mntbuf[i].f_mntonname);
else
return (NULL);
case FREE:
free(mntbuf);
free(mntcheck);
free(mntcount);
return (NULL);
default:
return (NULL);
}
}
int
namematch(struct hostent *hp)
{
char *cp, **np;
if ((hp == NULL) || (nfshost == NULL))
return (1);
if (strcasecmp(nfshost, hp->h_name) == 0)
return (1);
if ((cp = strchr(hp->h_name, '.')) != NULL) {
*cp = '\0';
if (strcasecmp(nfshost, hp->h_name) == 0)
return (1);
}
for (np = hp->h_aliases; *np; np++) {
if (strcasecmp(nfshost, *np) == 0)
return (1);
if ((cp = strchr(*np, '.')) != NULL) {
*cp = '\0';
if (strcasecmp(nfshost, *np) == 0)
return (1);
}
}
return (0);
}
void
checkmntlist(char *name, char **fromname, char **onname, char **type)
{
*fromname = getmntname(name, NULL, MNTFROM, type, NAME);
if (*fromname == NULL) {
*onname = getmntname(name, NULL, MNTON, type, NAME);
if (*onname != NULL)
*fromname = name;
} else
*onname = name;
}
size_t
mntinfo(struct statfs **mntbuf)
{
static struct statfs *origbuf;
size_t bufsize;
int mntsize;
mntsize = getfsstat(NULL, 0, MNT_NOWAIT);
if (mntsize <= 0)
return (0);
bufsize = (mntsize + 1) * sizeof(struct statfs);
if ((origbuf = malloc(bufsize)) == NULL)
err(1, "malloc");
mntsize = getfsstat(origbuf, (long)bufsize, MNT_NOWAIT);
*mntbuf = origbuf;
return (mntsize);
}
char *
getrealname(char *name, char *realname)
{
char *dirname;
int havedir;
size_t baselen;
size_t dirlen;
dirname = '\0';
havedir = 0;
if (*name == '/') {
if (ISDOT(name + 1) || ISDOTDOT(name + 1))
strcpy(realname, "/");
else {
if ((dirname = strrchr(name + 1, '/')) == NULL)
snprintf(realname, MAXPATHLEN, "%s", name);
else
havedir = 1;
}
} else {
if (ISDOT(name) || ISDOTDOT(name))
(void)realpath(name, realname);
else {
if ((dirname = strrchr(name, '/')) == NULL) {
if ((realpath(name, realname)) == NULL)
return (NULL);
} else
havedir = 1;
}
}
if (havedir) {
*dirname++ = '\0';
if (ISDOT(dirname)) {
*dirname = '\0';
if ((realpath(name, realname)) == NULL)
return (NULL);
} else if (ISDOTDOT(dirname)) {
*--dirname = '/';
if ((realpath(name, realname)) == NULL)
return (NULL);
} else {
if ((realpath(name, realname)) == NULL)
return (NULL);
baselen = strlen(realname);
dirlen = strlen(dirname);
if (baselen + dirlen + 1 > MAXPATHLEN)
return (NULL);
if (realname[1] == '\0') {
memmove(realname + 1, dirname, dirlen);
realname[dirlen + 1] = '\0';
} else {
realname[baselen] = '/';
memmove(realname + baselen + 1,
dirname, dirlen);
realname[baselen + dirlen + 1] = '\0';
}
}
}
return (realname);
}
/*
* xdr routines for mount rpc's
*/
int
xdr_dir(XDR *xdrsp, char *dirp)
{
return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN));
}
void
usage()
{
(void)fprintf(stderr, "%s\n%s\n",
"usage: umount [-fv] special | node",
" umount -a | -A [-fv] [-h host] [-t type]");
exit(1);
}