shadow/libmisc/chowndir.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.
 */
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[1024];
	int rc = 0;
	struct DIRECT *ent;
	struct stat sb;
	DIR *dir;

	/*
	 * Make certain the directory exists.  This routine is called
	 * directory by the invoker, or recursively.
	 */

	if (access (root, F_OK) != 0) {
		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 it is owned by
	 * old user ID.
	 */

	dir = opendir (root);
	if (NULL == dir) {
		return -1;
	}

	while ((ent = readdir (dir))) {

		/*
		 * 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.
		 */

		if (strlen (root) + strlen (ent->d_name) + 2 > sizeof new_name) {
			break;
		}

		snprintf (new_name, sizeof new_name, "%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
		if (sb.st_uid == old_uid) {
			LCHOWN (new_name, new_uid,
			        (sb.st_gid == old_gid) ? new_gid : sb.st_gid);
		}
	}
	(void) closedir (dir);

	/*
	 * Now do the root of the tree
	 */

	if (stat (root, &sb) == 0) {
		if (sb.st_uid == old_uid) {
			LCHOWN (root, new_uid,
			        sb.st_gid == old_gid ? new_gid : sb.st_gid);
		}
	}
	return rc;
}