diff --git a/usr.bin/mktemp/mktemp.1 b/usr.bin/mktemp/mktemp.1 index c8d7f6232632..469d4f6097d0 100644 --- a/usr.bin/mktemp/mktemp.1 +++ b/usr.bin/mktemp/mktemp.1 @@ -1,207 +1,207 @@ .\" Copyright (c) 1989, 1991, 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. .\" .\" From: $OpenBSD: mktemp.1,v 1.8 1998/03/19 06:13:37 millert Exp $ .\" $FreeBSD$ .\" -.Dd December 30, 2005 +.Dd August 4, 2022 .Dt MKTEMP 1 .Os .Sh NAME .Nm mktemp .Nd make temporary file name (unique) .Sh SYNOPSIS .Nm .Op Fl d .Op Fl q .Op Fl t Ar prefix .Op Fl u .Ar template ... .Nm .Op Fl d .Op Fl q .Op Fl u .Fl t Ar prefix .Sh DESCRIPTION The .Nm utility takes each of the given file name templates and overwrites a portion of it to create a file name. This file name is unique and suitable for use by the application. The template may be any file name with some number of .Ql X Ns s appended to it, for example .Pa /tmp/temp.XXXX . The trailing .Ql X Ns s are replaced with the current process number and/or a unique letter combination. The number of unique file names .Nm can return depends on the number of .Ql X Ns s provided; six .Ql X Ns s will result in .Nm selecting 1 of 56800235584 (62 ** 6) possible file names. .Pp If .Nm can successfully generate a unique file name, the file is created with mode 0600 (unless the .Fl u flag is given) and the filename is printed to standard output. .Pp If the .Fl t Ar prefix option is given, .Nm will generate a template string based on the .Ar prefix and the .Ev TMPDIR environment variable if set. The default location if .Ev TMPDIR is not set is .Pa /tmp . Care should be taken to ensure that it is appropriate to use an environment variable potentially supplied by the user. .Pp If no arguments are passed or if only the .Fl d flag is passed .Nm behaves as if .Fl t Li tmp was supplied. .Pp Any number of temporary files may be created in a single invocation, including one based on the internal template resulting from the .Fl t flag. .Pp The .Nm utility is provided to allow shell scripts to safely use temporary files. Traditionally, many shell scripts take the name of the program with the pid as a suffix and use that as a temporary file name. This kind of naming scheme is predictable and the race condition it creates is easy for an attacker to win. A safer, though still inferior, approach is to make a temporary directory using the same naming scheme. While this does allow one to guarantee that a temporary file will not be subverted, it still allows a simple denial of service attack. For these reasons it is suggested that .Nm be used instead. .Sh OPTIONS The available options are as follows: .Bl -tag -width indent -.It Fl d +.It Fl d , Fl -directory Make a directory instead of a file. -.It Fl q +.It Fl q , Fl -quiet Fail silently if an error occurs. This is useful if a script does not want error output to go to standard error. .It Fl t Ar prefix Generate a template (using the supplied .Ar prefix and .Ev TMPDIR if set) to create a filename template. -.It Fl u +.It Fl u , Fl -dry-run Operate in .Dq unsafe mode. The temp file will be unlinked before .Nm exits. This is slightly better than .Xr mktemp 3 but still introduces a race condition. Use of this option is not encouraged. .El .Sh EXIT STATUS .Ex -std .Sh EXAMPLES The following .Xr sh 1 fragment illustrates a simple use of .Nm where the script should quit if it cannot get a safe temporary file. .Bd -literal -offset indent tempfoo=`basename $0` TMPFILE=`mktemp /tmp/${tempfoo}.XXXXXX` || exit 1 echo "program output" >> $TMPFILE .Ed .Pp To allow the use of $TMPDIR: .Bd -literal -offset indent tempfoo=`basename $0` TMPFILE=`mktemp -t ${tempfoo}` || exit 1 echo "program output" >> $TMPFILE .Ed .Pp In this case, we want the script to catch the error itself. .Bd -literal -offset indent tempfoo=`basename $0` TMPFILE=`mktemp -q /tmp/${tempfoo}.XXXXXX` if [ $? -ne 0 ]; then echo "$0: Can't create temp file, exiting..." exit 1 fi .Ed .Sh SEE ALSO .Xr mkdtemp 3 , .Xr mkstemp 3 , .Xr mktemp 3 , .Xr environ 7 .Sh HISTORY A .Nm utility appeared in .Ox 2.1 . This implementation was written independently based on the .Ox man page, and first appeared in .Fx 2.2.7 . This man page is taken from .Ox . diff --git a/usr.bin/mktemp/mktemp.c b/usr.bin/mktemp/mktemp.c index 754cc8da7e4e..9240197e9129 100644 --- a/usr.bin/mktemp/mktemp.c +++ b/usr.bin/mktemp/mktemp.c @@ -1,158 +1,166 @@ /*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 1994, 1995, 1996, 1998 Peter Wemm * 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. * * 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. * */ /* * This program was originally written long ago, originally for a non * BSD-like OS without mkstemp(). It's been modified over the years * to use mkstemp() rather than the original O_CREAT|O_EXCL/fstat/lstat * etc style hacks. * A cleanup, misc options and mkdtemp() calls were added to try and work * more like the OpenBSD version - which was first to publish the interface. */ #include +#include #include #include #include #include #include #ifndef lint static const char rcsid[] = "$FreeBSD$"; #endif /* not lint */ static void usage(void); +static const struct option long_opts[] = { + {"directory", no_argument, NULL, 'd'}, + {"quiet", no_argument, NULL, 'q'}, + {"dry-run", no_argument, NULL, 'u'}, + {NULL, no_argument, NULL, 0}, +}; + int main(int argc, char **argv) { int c, fd, ret; char *tmpdir; const char *prefix; char *name; int dflag, qflag, tflag, uflag; ret = dflag = qflag = tflag = uflag = 0; prefix = "mktemp"; name = NULL; - while ((c = getopt(argc, argv, "dqt:u")) != -1) + while ((c = getopt_long(argc, argv, "dqt:u", long_opts, NULL)) != -1) switch (c) { case 'd': dflag++; break; case 'q': qflag++; break; case 't': prefix = optarg; tflag++; break; case 'u': uflag++; break; default: usage(); } argc -= optind; argv += optind; if (!tflag && argc < 1) { tflag = 1; prefix = "tmp"; } if (tflag) { tmpdir = getenv("TMPDIR"); if (tmpdir == NULL) asprintf(&name, "%s%s.XXXXXXXXXX", _PATH_TMP, prefix); else asprintf(&name, "%s/%s.XXXXXXXXXX", tmpdir, prefix); /* if this fails, the program is in big trouble already */ if (name == NULL) { if (qflag) return (1); else errx(1, "cannot generate template"); } } /* generate all requested files */ while (name != NULL || argc > 0) { if (name == NULL) { name = strdup(argv[0]); argv++; argc--; } if (dflag) { if (mkdtemp(name) == NULL) { ret = 1; if (!qflag) warn("mkdtemp failed on %s", name); } else { printf("%s\n", name); if (uflag) rmdir(name); } } else { fd = mkstemp(name); if (fd < 0) { ret = 1; if (!qflag) warn("mkstemp failed on %s", name); } else { close(fd); if (uflag) unlink(name); printf("%s\n", name); } } if (name) free(name); name = NULL; } return (ret); } static void usage(void) { fprintf(stderr, "usage: mktemp [-d] [-q] [-t prefix] [-u] template ...\n"); fprintf(stderr, " mktemp [-d] [-q] [-u] -t prefix \n"); exit (1); }