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/*
* Copyright (c) 2003 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Marshall
* Kirk McKusick and Network Associates Laboratories, the Security
* Research Division of Network Associates, Inc. under DARPA/SPAWAR
* contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
* research program.
*
* 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. The names of the authors may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <ufs/ufs/ufsmount.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
void usage(void);
int
main(int argc, char **argv)
{
char *dir, *cp, path[PATH_MAX];
struct ufs_args args;
struct group *grp;
struct stat stbuf;
int fd;
if (argc != 3)
usage();
dir = argv[1];
args.fspec = argv[2];
/*
* Check that the user running this program has permission
* to create and remove a snapshot file from the directory
* in which they have requested to have it made. If the
* directory is sticky and not owned by the user, then they
* will not be able to remove the snapshot when they are
* done with it.
*/
if (strlen(args.fspec) >= PATH_MAX)
errx(1, "pathname too long %s", args.fspec);
cp = strrchr(args.fspec, '/');
if (cp == NULL) {
strlcpy(path, ".", PATH_MAX);
} else if (cp == args.fspec) {
strlcpy(path, "/", PATH_MAX);
} else {
strlcpy(path, args.fspec, cp - args.fspec + 1);
}
if (stat(path, &stbuf) < 0)
err(1, "%s", path);
if (!S_ISDIR(stbuf.st_mode))
errx(1, "%s: Not a directory", path);
if (access(path, W_OK) < 0)
err(1, "Lack write permission in %s", path);
if ((stbuf.st_mode & S_ISTXT) && stbuf.st_uid != getuid())
errx(1, "Lack write permission in %s: Sticky bit set", path);
/*
* Having verified access to the directory in which the
* snapshot is to be built, proceed with creating it.
*/
if ((grp = getgrnam("operator")) == NULL)
errx(1, "Cannot retrieve operator gid");
if (mount("ffs", dir, MNT_UPDATE | MNT_SNAPSHOT, &args) < 0)
err(1, "Cannot create %s", args.fspec);
if ((fd = open(args.fspec, O_RDONLY)) < 0)
err(1, "Cannot open %s", args.fspec);
if (fstat(fd, &stbuf) != 0)
err(1, "Cannot stat %s", args.fspec);
if ((stbuf.st_flags & SF_SNAPSHOT) == 0)
errx(1, "File %s is not a snapshot", args.fspec);
if (fchown(fd, -1, grp->gr_gid) != 0)
err(1, "Cannot chown %s", args.fspec);
if (fchmod(fd, S_IRUSR | S_IRGRP) != 0)
err(1, "Cannot chmod %s", args.fspec);
exit(EXIT_SUCCESS);
}
void
usage()
{
fprintf(stderr, "usage: mksnap_ffs mountpoint snapshot_name\n");
exit(EX_USAGE);
}
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