shadow/libmisc/chowndir.c
2011-08-14 14:00:14 +00:00

202 lines
5.3 KiB
C

/*
* Copyright (c) 1992 - 1993, Julianne Frances Haugh
* Copyright (c) 1996 - 2000, Marek Michałkiewicz
* Copyright (c) 2003 - 2005, Tomasz Kłoczko
* Copyright (c) 2010 - , Nicolas François
* 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. The name of the copyright holders or contributors may not be used to
* endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
* HOLDERS 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.
*/
#include <config.h>
#ident "$Id$"
#include <sys/types.h>
#include <sys/stat.h>
#include "prototypes.h"
#include "defines.h"
#include <fcntl.h>
#include <stdio.h>
/*
* chown_tree - change ownership of files in a directory tree
*
* chown_dir() walks a directory tree and changes the ownership
* of all files owned by the provided user ID.
*
* Only files owned (resp. group-owned) by old_uid (resp. by old_gid)
* will have their ownership (resp. group-ownership) modified, unless
* old_uid (resp. old_gid) is set to -1.
*
* new_uid and new_gid can be set to -1 to indicate that no owner or
* group-owner shall be changed.
*/
int chown_tree (const char *root,
uid_t old_uid,
uid_t new_uid,
gid_t old_gid,
gid_t new_gid)
{
char *new_name;
size_t new_name_len;
int rc = 0;
struct DIRECT *ent;
struct stat sb;
DIR *dir;
new_name = malloc (1024);
if (NULL == new_name) {
return -1;
}
new_name_len = 1024;
/*
* Make certain the directory exists. This routine is called
* directly by the invoker, or recursively.
*/
if (access (root, F_OK) != 0) {
free (new_name);
return -1;
}
/*
* Open the directory and read each entry. Every entry is tested
* to see if it is a directory, and if so this routine is called
* recursively. If not, it is checked to see if an ownership
* shall be changed.
*/
dir = opendir (root);
if (NULL == dir) {
free (new_name);
return -1;
}
while ((ent = readdir (dir))) {
size_t ent_name_len;
uid_t tmpuid = (uid_t) -1;
gid_t tmpgid = (gid_t) -1;
/*
* Skip the "." and ".." entries
*/
if ( (strcmp (ent->d_name, ".") == 0)
|| (strcmp (ent->d_name, "..") == 0)) {
continue;
}
/*
* Make the filename for both the source and the
* destination files.
*/
ent_name_len = strlen (root) + strlen (ent->d_name) + 2;
if (ent_name_len > new_name_len) {
/*@only@*/char *tmp = realloc (new_name, ent_name_len);
if (NULL == tmp) {
rc = -1;
break;
}
new_name = tmp;
new_name_len = ent_name_len;
}
(void) snprintf (new_name, new_name_len, "%s/%s", root, ent->d_name);
/* Don't follow symbolic links! */
if (LSTAT (new_name, &sb) == -1) {
continue;
}
if (S_ISDIR (sb.st_mode) && !S_ISLNK (sb.st_mode)) {
/*
* Do the entire subdirectory.
*/
rc = chown_tree (new_name, old_uid, new_uid,
old_gid, new_gid);
if (0 != rc) {
break;
}
}
#ifndef HAVE_LCHOWN
/* don't use chown (follows symbolic links!) */
if (S_ISLNK (sb.st_mode)) {
continue;
}
#endif
/*
* By default, the IDs are not changed (-1).
*
* If the file is not owned by the user, the owner is not
* changed.
*
* If the file is not group-owned by the group, the
* group-owner is not changed.
*/
if (((uid_t) -1 == old_uid) || (sb.st_uid == old_uid)) {
tmpuid = new_uid;
}
if (((gid_t) -1 == old_gid) || (sb.st_gid == old_gid)) {
tmpgid = new_gid;
}
if (((uid_t) -1 != tmpuid) || ((gid_t) -1 != tmpgid)) {
rc = LCHOWN (new_name, tmpuid, tmpgid);
if (0 != rc) {
break;
}
}
}
free (new_name);
(void) closedir (dir);
/*
* Now do the root of the tree
*/
if ((0 == rc) && (stat (root, &sb) == 0)) {
uid_t tmpuid = (uid_t) -1;
gid_t tmpgid = (gid_t) -1;
if (((uid_t) -1 == old_uid) || (sb.st_uid == old_uid)) {
tmpuid = new_uid;
}
if (((gid_t) -1 == old_gid) || (sb.st_gid == old_gid)) {
tmpgid = new_gid;
}
if (((uid_t) -1 != tmpuid) || ((gid_t) -1 != tmpgid)) {
rc = LCHOWN (root, tmpuid, tmpgid);
}
} else {
rc = -1;
}
return rc;
}