freebsd-skq/usr.sbin/chown/chown.c
Bruce Evans ccee498fca Backed out previous commit. chown(8) doesn't follow symlinks by
default, at least in BSD.  This used to be automatic, because chown(2)
didn't follow symlinks.  When chown(2) was changed to follow symlinks
in BSD4.4, chown(8) was changed to not follow symlinks by default.
The previous commit broke this.  The first victim was bsd.prog.mk,
which uses a plain chown in an attempt to change the ownership of the
symlinks to `dm' in /usr/games.  This fails when it is done before
dm is installed, or messes up the ownership of dm if dm is installed.

Unfixed problems:
1. When lchown(2) was implemented, chown(8) wasn't changed to implement
   the historical behaviour of changing ownership of symlinks.  I'm not
   sure if it should have been.  The -HLP options give more complete
   control, but they unfortunately don't apply unless the -R option is
   specified (a problem shared with other commands, e.g., cp; I guess
   we're supposed to use -R even for non-recursive traversals).
2. If we implement the historical behaviour, then -h would become a no-op
   and should be left undocumented.
3. The man page suggests that without option -h, all symlinks (to files
   specified in the command line?) are followed.  It's not clear what
   "the file" is.  These bugs were introduced when -h was documented.
4. The correct interaction of -h with the other flags is not clear.
1998-05-03 04:17:48 +00:00

274 lines
6.4 KiB
C

/*
* Copyright (c) 1988, 1993, 1994
* 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) 1988, 1993, 1994\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)chown.c 8.8 (Berkeley) 4/4/94";
#else
static const char rcsid[] =
"$Id: chown.c,v 1.11 1998/05/02 12:57:57 helbig Exp $";
#endif
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fts.h>
#include <grp.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
void a_gid __P((char *));
void a_uid __P((char *));
void chownerr __P((char *));
u_long id __P((char *, char *));
void usage __P((void));
uid_t uid;
gid_t gid;
int Rflag, ischown, fflag, hflag;
char *gname, *myname;
int
main(argc, argv)
int argc;
char *argv[];
{
FTS *ftsp;
FTSENT *p;
int Hflag, Lflag, Pflag, ch, fts_options, hflag, rval;
char *cp;
myname = (cp = rindex(*argv, '/')) ? cp + 1 : *argv;
ischown = myname[2] == 'o';
Hflag = Lflag = Pflag = hflag = 0;
while ((ch = getopt(argc, argv, "HLPRfh")) != -1)
switch (ch) {
case 'H':
Hflag = 1;
Lflag = Pflag = 0;
break;
case 'L':
Lflag = 1;
Hflag = Pflag = 0;
break;
case 'P':
Pflag = 1;
Hflag = Lflag = 0;
break;
case 'R':
Rflag = 1;
break;
case 'f':
fflag = 1;
break;
case 'h':
hflag = 1;
break;
case '?':
default:
usage();
}
argv += optind;
argc -= optind;
if (argc < 2)
usage();
fts_options = FTS_PHYSICAL;
if (Rflag) {
if (hflag && (Lflag || Hflag))
errx(1, "the -R and -h options may not be specified together");
if (Hflag)
fts_options |= FTS_COMFOLLOW;
if (Lflag) {
fts_options &= ~FTS_PHYSICAL;
fts_options |= FTS_LOGICAL;
}
}
uid = gid = -1;
if (ischown) {
if ((cp = strchr(*argv, ':')) != NULL) {
*cp++ = '\0';
a_gid(cp);
}
#ifdef SUPPORT_DOT
else if ((cp = strchr(*argv, '.')) != NULL) {
*cp++ = '\0';
a_gid(cp);
}
#endif
a_uid(*argv);
} else
a_gid(*argv);
if ((ftsp = fts_open(++argv, fts_options, 0)) == NULL)
err(1, NULL);
for (rval = 0; (p = fts_read(ftsp)) != NULL;) {
switch (p->fts_info) {
case FTS_D: /* Change it at FTS_DP. */
if (!Rflag)
fts_set(ftsp, p, FTS_SKIP);
continue;
case FTS_DNR: /* Warn, chown, continue. */
warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
rval = 1;
break;
case FTS_ERR: /* Warn, continue. */
case FTS_NS:
warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
rval = 1;
continue;
case FTS_SL: /* Ignore. */
case FTS_SLNONE:
/*
* The only symlinks that end up here are ones that
* don't point to anything and ones that we found
* doing a physical walk.
*/
if (hflag)
break;
else
continue;
default:
break;
}
if (hflag) {
if (lchown(p->fts_accpath, uid, gid) && !fflag) {
chownerr(p->fts_path);
rval = 1;
}
} else {
if (chown(p->fts_accpath, uid, gid) && !fflag) {
chownerr(p->fts_path);
rval = 1;
}
}
}
if (errno)
err(1, "fts_read");
exit(rval);
}
void
a_gid(s)
char *s;
{
struct group *gr;
if (*s == '\0') /* Argument was "uid[:.]". */
return;
gname = s;
gid = ((gr = getgrnam(s)) == NULL) ? id(s, "group") : gr->gr_gid;
}
void
a_uid(s)
char *s;
{
struct passwd *pw;
if (*s == '\0') /* Argument was "[:.]gid". */
return;
uid = ((pw = getpwnam(s)) == NULL) ? id(s, "user") : pw->pw_uid;
}
u_long
id(name, type)
char *name, *type;
{
u_long val;
char *ep;
/*
* XXX
* We know that uid_t's and gid_t's are unsigned longs.
*/
errno = 0;
val = strtoul(name, &ep, 10);
if (errno)
err(1, "%s", name);
if (*ep != '\0')
errx(1, "%s: illegal %s name", name, type);
return (val);
}
void
chownerr(file)
char *file;
{
static int euid = -1, ngroups = -1;
gid_t groups[NGROUPS];
/* Check for chown without being root. */
if (errno != EPERM ||
(uid != -1 && euid == -1 && (euid = geteuid()) != 0))
err(1, "%s", file);
/* Check group membership; kernel just returns EPERM. */
if (gid != -1 && ngroups == -1 &&
euid == -1 && (euid = geteuid()) != 0) {
ngroups = getgroups(NGROUPS, groups);
while (--ngroups >= 0 && gid != groups[ngroups]);
if (ngroups < 0)
errx(1, "you are not a member of group %s", gname);
}
warn("%s", file);
}
void
usage()
{
(void)fprintf(stderr, "%s\n%s\n%s\n",
"usage: chown [-R [-H | -L | -P]] [-f] [-h] owner[:group] file ...",
" chown [-R [-H | -L | -P]] [-f] [-h] :group file ...",
" chgrp [-R [-H | -L | -P]] [-f] [-h] group file ...");
exit(1);
}