nfs-utils/SOURCES/nfs-utils-1.3.0/utils/mount/nfsumount.c - actifio - Git at Google

 /*
  * nfsumount.c -- Linux NFS umount
  * Copyright (C) 2006 Amit Gud <agud@redhat.com>
  *
  * - Basic code and wrapper around NFS umount code originally
  *   in util-linux/mount/nfsmount.c
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2, or (at your option)
  * any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  */

 #include <unistd.h>
 #include <stdio.h>
 #include <errno.h>
 #include <getopt.h>
 #include <mntent.h>
 #include <sys/mount.h>
 #include <ctype.h>
 #include <pwd.h>

 #include "xcommon.h"
 #include "fstab.h"
 #include "nls.h"

 #include "mount_constants.h"
 #include "nfs_mount.h"
 #include "mount.h"
 #include "error.h"
 #include "network.h"
 #include "parse_opt.h"
 #include "parse_dev.h"
 #include "utils.h"

 #define MOUNTSFILE	"/proc/mounts"
 #define LINELEN		(4096)

 #if !defined(MNT_FORCE)
 /* dare not try to include <linux/mount.h> -- lots of errors */
 #define MNT_FORCE 1
 #endif

 #if !defined(MNT_DETACH)
 #define MNT_DETACH 2
 #endif

 extern char *progname;
 extern int nomtab;
 extern int verbose;
 int force;
 int lazy;
 int remount;


 static int try_remount(const char *spec, const char *node)
 {
 	int res;

 	res = mount(spec, node, NULL,
 		    MS_MGC_VAL | MS_REMOUNT | MS_RDONLY, NULL);
 	if (res == 0) {
 		struct mntent remnt;
 		nfs_error(_("%s: %s busy - remounted read-only"),
 				progname, spec);
 		remnt.mnt_type = remnt.mnt_fsname = NULL;
 		remnt.mnt_dir = xstrdup(node);
 		remnt.mnt_opts = xstrdup("ro");
 		if (!nomtab)
 			update_mtab(node, &remnt);
 	} else if (errno != EBUSY) {    /* hmm ... */
 		perror(_("remount"));
 		nfs_error(_("%s: could not remount %s read-only"),
 				progname, spec);
 	}
 	return res;
 }

 static int del_mtab(const char *spec, const char *node)
 {
 	int umnt_err, res;

 	umnt_err = 0;
 	if (lazy) {
 		res = umount2 (node, MNT_DETACH);
 		if (res < 0)
 			umnt_err = errno;
 		goto writemtab;
 	}

 	if (force) {
 		res = umount2 (node, MNT_FORCE);
 		if (res == -1) {
 			int errsv = errno;
 			perror(_("umount2"));
 			errno = errsv;
 			if (errno == ENOSYS) {
 				if (verbose)
 					printf(_("no umount2, trying umount...\n"));
 				res = umount (node);
 			}
 		}
 	} else
 		res = umount (node);

 	if (res < 0) {
 		if (remount && errno == EBUSY && spec) {
 			res = try_remount(spec, node);
 			if (res)
 				goto writemtab;
 			return EX_SUCCESS;
 		} else
 			umnt_err = errno;
 	}

 	if (res >= 0) {
 		/* Umount succeeded */
 		if (verbose)
 			printf(_("%s umounted\n"), spec ? spec : node);
 	}

  writemtab:
 	if (!nomtab &&
 	    (umnt_err == 0 || umnt_err == EINVAL || umnt_err == ENOENT)) {
 		update_mtab(node, NULL);
 	}

 	if (res >= 0)
 		return EX_SUCCESS;

 	if (umnt_err)
 		umount_error(umnt_err, node);
 	return EX_FILEIO;
 }

 /*
  * Detect NFSv4 mounts.
  *
  * Consult /proc/mounts to determine if the mount point
  * is an NFSv4 mount.  The kernel is authoritative about
  * what type of mount this is.
  *
  * Returns 1 if "mc" is an NFSv4 mount, zero if not, and
  * -1 if some error occurred.
  */
 static int nfs_umount_is_vers4(const struct mntentchn *mc)
 {
 	struct mntentchn *pmc;
 	struct mount_options *options;
 	int retval;

 	retval = -1;
 	pmc = getprocmntdirbackward(mc->m.mnt_dir, NULL);
 	if (!pmc)
 		goto not_found;

 	do {
 		size_t nlen = strlen(pmc->m.mnt_fsname);

 		/*
 		 * It's possible the mount location string in /proc/mounts
 		 * ends with a '/'. In this case, if the entry came from
 		 * /etc/mtab, it won't have the trailing '/' so deal with
 		 * it.
 		 */
 		while (pmc->m.mnt_fsname[nlen - 1] == '/')
 			nlen--;
 		if (strncmp(pmc->m.mnt_fsname, mc->m.mnt_fsname, nlen) != 0)
 			continue;

 		if (strcmp(pmc->m.mnt_type, "nfs4") == 0)
 			goto out_nfs4;

 		options = po_split(pmc->m.mnt_opts);
 		if (options != NULL) {
 			unsigned long version;
 			int rc = nfs_nfs_version(options, &version);
 			po_destroy(options);
 			if (rc && version == 4)
 				goto out_nfs4;
 		}

 		if (strcmp(pmc->m.mnt_type, "nfs") == 0)
 			goto out_nfs;
 	} while ((pmc = getprocmntdirbackward(mc->m.mnt_dir, pmc)) != NULL);

 	if (retval == -1) {
 not_found:
 		fprintf(stderr, "%s was not found in %s\n",
 			mc->m.mnt_dir, MOUNTSFILE);
 		goto out;
 	}

 out_nfs4:
 	if (verbose)
 		fprintf(stderr, "NFSv4 mount point detected\n");
 	retval = 1;
 	goto out;

 out_nfs:
 	if (verbose)
 		fprintf(stderr, "Legacy NFS mount point detected\n");
 	retval = 0;

 out:
 	return retval;
 }

 static struct option umount_longopts[] =
 {
   { "force", 0, 0, 'f' },
   { "help", 0, 0, 'h' },
   { "no-mtab", 0, 0, 'n' },
   { "verbose", 0, 0, 'v' },
   { "read-only", 0, 0, 'r' },
   { NULL, 0, 0, 0 }
 };

 int nfsumount(int argc, char *argv[])
 {
 	int c, ret;
 	char *spec;
 	struct mntentchn *mc;

 	if (argc < 2) {
 		umount_usage();
 		return EX_USAGE;
 	}

 	spec = argv[1];

 	argv += 1;
 	argc -= 1;

 	argv[0] = argv[-1]; /* So that getopt error messages are correct */
 	while ((c = getopt_long (argc, argv, "fvnrlh",
 				umount_longopts, NULL)) != -1) {

 		switch (c) {
 		case 'f':
 			++force;
 			break;
 		case 'v':
 			++verbose;
 			break;
 		case 'n':
 			++nomtab;
 			break;
 		case 'r':
 			++remount;
 			break;
 		case 'l':
 			++lazy;
 			break;
 		case 'h':
 		default:
 			umount_usage();
 			return EX_USAGE;
 		}
 	}
 	if (optind != argc) {
 		umount_usage();
 		return EX_USAGE;
 	}

 	if (spec == NULL || (*spec != '/' && strchr(spec,':') == NULL)) {
 		nfs_error(_("%s: %s: not found\n"), progname, spec);
 		return EX_USAGE;
 	}

 	if (*spec == '/')
 		mc = getmntdirbackward(spec, NULL);
 	else
 		mc = getmntdevbackward(spec, NULL);
 	if (!mc && verbose)
 		printf(_("Could not find %s in mtab\n"), spec);

 	if (mc && strcmp(mc->m.mnt_type, "nfs") != 0 &&
 	    strcmp(mc->m.mnt_type, "nfs4") != 0) {
 		nfs_error(_("%s: %s on %s is not an NFS filesystem"),
 				progname, mc->m.mnt_fsname, mc->m.mnt_dir);
 		return EX_USAGE;
 	}

 	if (getuid() != 0) {
 		/* only permitted if "user=" or "users" is in mount options */
 		if (!mc) {
 			/* umount might call us twice.  The second time there will
 			 * be no entry in mtab and we should just exit quietly
 			 */
 			return EX_SUCCESS;

 		only_root:
 			nfs_error(_("%s: You are not permitted to unmount %s"),
 					progname, spec);
 			return EX_USAGE;
 		}
 		if (hasmntopt(&mc->m, "users") == NULL) {
 			char *opt = hasmntopt(&mc->m, "user");
 			struct passwd *pw;
 			char *comma;
 			size_t len;
 			if (!opt)
 				goto only_root;
 			if (opt[4] != '=')
 				goto only_root;
 			comma = strchr(opt, ',');
 			if (comma)
 				len = comma - (opt + 5);
 			else
 				len = strlen(opt+5);
 			pw = getpwuid(getuid());
 			if (pw == NULL || strlen(pw->pw_name) != len
 			    || strncmp(pw->pw_name, opt+5, len) != 0)
 				goto only_root;
 		}
 	}

 	ret = EX_SUCCESS;
 	if (mc) {
 		if (!lazy) {
 			switch (nfs_umount_is_vers4(mc)) {
 			case 0:
 				/* We ignore the error from nfs_umount23.
 				 * If the actual umount succeeds (in del_mtab),
 				 * we don't want to signal an error, as that
 				 * could cause /sbin/mount to retry!
 				 */
 				nfs_umount23(mc->m.mnt_fsname, mc->m.mnt_opts);
 				break;
 			case 1:
 				break;
 			default:
 				return EX_FAIL;
 			}
 		}
 		ret = del_mtab(mc->m.mnt_fsname, mc->m.mnt_dir);
 	} else if (*spec != '/') {
 		if (!lazy)
 			ret = nfs_umount23(spec, "tcp,v3");
 	} else
 		ret = del_mtab(NULL, spec);

 	return ret;
 }
	/*
	* nfsumount.c -- Linux NFS umount
	* Copyright (C) 2006 Amit Gud <agud@redhat.com>
	*
	* - Basic code and wrapper around NFS umount code originally
	* in util-linux/mount/nfsmount.c
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2, or (at your option)
	* any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	*/

	#include <unistd.h>
	#include <stdio.h>
	#include <errno.h>
	#include <getopt.h>
	#include <mntent.h>
	#include <sys/mount.h>
	#include <ctype.h>
	#include <pwd.h>

	#include "xcommon.h"
	#include "fstab.h"
	#include "nls.h"

	#include "mount_constants.h"
	#include "nfs_mount.h"
	#include "mount.h"
	#include "error.h"
	#include "network.h"
	#include "parse_opt.h"
	#include "parse_dev.h"
	#include "utils.h"

	#define MOUNTSFILE "/proc/mounts"
	#define LINELEN (4096)

	#if !defined(MNT_FORCE)
	/* dare not try to include <linux/mount.h> -- lots of errors */
	#define MNT_FORCE 1
	#endif

	#if !defined(MNT_DETACH)
	#define MNT_DETACH 2
	#endif

	extern char *progname;
	extern int nomtab;
	extern int verbose;
	int force;
	int lazy;
	int remount;


	static int try_remount(const char spec, const char node)
	{
	int res;

	res = mount(spec, node, NULL,
	MS_MGC_VAL \| MS_REMOUNT \| MS_RDONLY, NULL);
	if (res == 0) {
	struct mntent remnt;
	nfs_error(_("%s: %s busy - remounted read-only"),
	progname, spec);
	remnt.mnt_type = remnt.mnt_fsname = NULL;
	remnt.mnt_dir = xstrdup(node);
	remnt.mnt_opts = xstrdup("ro");
	if (!nomtab)
	update_mtab(node, &remnt);
	} else if (errno != EBUSY) { /* hmm ... */
	perror(_("remount"));
	nfs_error(_("%s: could not remount %s read-only"),
	progname, spec);
	}
	return res;
	}

	static int del_mtab(const char spec, const char node)
	{
	int umnt_err, res;

	umnt_err = 0;
	if (lazy) {
	res = umount2 (node, MNT_DETACH);
	if (res < 0)
	umnt_err = errno;
	goto writemtab;
	}

	if (force) {
	res = umount2 (node, MNT_FORCE);
	if (res == -1) {
	int errsv = errno;
	perror(_("umount2"));
	errno = errsv;
	if (errno == ENOSYS) {
	if (verbose)
	printf(_("no umount2, trying umount...\n"));
	res = umount (node);
	}
	}
	} else
	res = umount (node);

	if (res < 0) {
	if (remount && errno == EBUSY && spec) {
	res = try_remount(spec, node);
	if (res)
	goto writemtab;
	return EX_SUCCESS;
	} else
	umnt_err = errno;
	}

	if (res >= 0) {
	/* Umount succeeded */
	if (verbose)
	printf(_("%s umounted\n"), spec ? spec : node);
	}

	writemtab:
	if (!nomtab &&
	(umnt_err == 0 \|\| umnt_err == EINVAL \|\| umnt_err == ENOENT)) {
	update_mtab(node, NULL);
	}

	if (res >= 0)
	return EX_SUCCESS;

	if (umnt_err)
	umount_error(umnt_err, node);
	return EX_FILEIO;
	}

	/*
	* Detect NFSv4 mounts.
	*
	* Consult /proc/mounts to determine if the mount point
	* is an NFSv4 mount. The kernel is authoritative about
	* what type of mount this is.
	*
	* Returns 1 if "mc" is an NFSv4 mount, zero if not, and
	* -1 if some error occurred.
	*/
	static int nfs_umount_is_vers4(const struct mntentchn *mc)
	{
	struct mntentchn *pmc;
	struct mount_options *options;
	int retval;

	retval = -1;
	pmc = getprocmntdirbackward(mc->m.mnt_dir, NULL);
	if (!pmc)
	goto not_found;

	do {
	size_t nlen = strlen(pmc->m.mnt_fsname);

	/*
	* It's possible the mount location string in /proc/mounts
	* ends with a '/'. In this case, if the entry came from
	* /etc/mtab, it won't have the trailing '/' so deal with
	* it.
	*/
	while (pmc->m.mnt_fsname[nlen - 1] == '/')
	nlen--;
	if (strncmp(pmc->m.mnt_fsname, mc->m.mnt_fsname, nlen) != 0)
	continue;

	if (strcmp(pmc->m.mnt_type, "nfs4") == 0)
	goto out_nfs4;

	options = po_split(pmc->m.mnt_opts);
	if (options != NULL) {
	unsigned long version;
	int rc = nfs_nfs_version(options, &version);
	po_destroy(options);
	if (rc && version == 4)
	goto out_nfs4;
	}

	if (strcmp(pmc->m.mnt_type, "nfs") == 0)
	goto out_nfs;
	} while ((pmc = getprocmntdirbackward(mc->m.mnt_dir, pmc)) != NULL);

	if (retval == -1) {
	not_found:
	fprintf(stderr, "%s was not found in %s\n",
	mc->m.mnt_dir, MOUNTSFILE);
	goto out;
	}

	out_nfs4:
	if (verbose)
	fprintf(stderr, "NFSv4 mount point detected\n");
	retval = 1;
	goto out;

	out_nfs:
	if (verbose)
	fprintf(stderr, "Legacy NFS mount point detected\n");
	retval = 0;

	out:
	return retval;
	}

	static struct option umount_longopts[] =
	{
	{ "force", 0, 0, 'f' },
	{ "help", 0, 0, 'h' },
	{ "no-mtab", 0, 0, 'n' },
	{ "verbose", 0, 0, 'v' },
	{ "read-only", 0, 0, 'r' },
	{ NULL, 0, 0, 0 }
	};

	int nfsumount(int argc, char *argv[])
	{
	int c, ret;
	char *spec;
	struct mntentchn *mc;

	if (argc < 2) {
	umount_usage();
	return EX_USAGE;
	}

	spec = argv[1];

	argv += 1;
	argc -= 1;

	argv[0] = argv[-1]; /* So that getopt error messages are correct */
	while ((c = getopt_long (argc, argv, "fvnrlh",
	umount_longopts, NULL)) != -1) {

	switch (c) {
	case 'f':
	++force;
	break;
	case 'v':
	++verbose;
	break;
	case 'n':
	++nomtab;
	break;
	case 'r':
	++remount;
	break;
	case 'l':
	++lazy;
	break;
	case 'h':
	default:
	umount_usage();
	return EX_USAGE;
	}
	}
	if (optind != argc) {
	umount_usage();
	return EX_USAGE;
	}

	if (spec == NULL \|\| (*spec != '/' && strchr(spec,':') == NULL)) {
	nfs_error(_("%s: %s: not found\n"), progname, spec);
	return EX_USAGE;
	}

	if (*spec == '/')
	mc = getmntdirbackward(spec, NULL);
	else
	mc = getmntdevbackward(spec, NULL);
	if (!mc && verbose)
	printf(_("Could not find %s in mtab\n"), spec);

	if (mc && strcmp(mc->m.mnt_type, "nfs") != 0 &&
	strcmp(mc->m.mnt_type, "nfs4") != 0) {
	nfs_error(_("%s: %s on %s is not an NFS filesystem"),
	progname, mc->m.mnt_fsname, mc->m.mnt_dir);
	return EX_USAGE;
	}

	if (getuid() != 0) {
	/* only permitted if "user=" or "users" is in mount options */
	if (!mc) {
	/* umount might call us twice. The second time there will
	* be no entry in mtab and we should just exit quietly
	*/
	return EX_SUCCESS;

	only_root:
	nfs_error(_("%s: You are not permitted to unmount %s"),
	progname, spec);
	return EX_USAGE;
	}
	if (hasmntopt(&mc->m, "users") == NULL) {
	char *opt = hasmntopt(&mc->m, "user");
	struct passwd *pw;
	char *comma;
	size_t len;
	if (!opt)
	goto only_root;
	if (opt[4] != '=')
	goto only_root;
	comma = strchr(opt, ',');
	if (comma)
	len = comma - (opt + 5);
	else
	len = strlen(opt+5);
	pw = getpwuid(getuid());
	if (pw == NULL \|\| strlen(pw->pw_name) != len
	\|\| strncmp(pw->pw_name, opt+5, len) != 0)
	goto only_root;
	}
	}

	ret = EX_SUCCESS;
	if (mc) {
	if (!lazy) {
	switch (nfs_umount_is_vers4(mc)) {
	case 0:
	/* We ignore the error from nfs_umount23.
	* If the actual umount succeeds (in del_mtab),
	* we don't want to signal an error, as that
	* could cause /sbin/mount to retry!
	*/
	nfs_umount23(mc->m.mnt_fsname, mc->m.mnt_opts);
	break;
	case 1:
	break;
	default:
	return EX_FAIL;
	}
	}
	ret = del_mtab(mc->m.mnt_fsname, mc->m.mnt_dir);
	} else if (*spec != '/') {
	if (!lazy)
	ret = nfs_umount23(spec, "tcp,v3");
	} else
	ret = del_mtab(NULL, spec);

	return ret;
	}