/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 1997-2001 by Sun Microsystems, Inc.
* All rights reserved.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright (c) 2013 RackTop Systems.
*/
#include <errno.h>
#include <sys/types.h>
#include <stdio.h>
#include <userdefs.h>
#include <pwd.h>
#include <libcmdutils.h>
static int findunuseduid(uid_t start, uid_t stop, uid_t *ret);
static boolean_t isreserveduid(uid_t uid);
/*
* Find the highest unused uid. If the highest unused uid is "stop",
* then attempt to find a hole in the range. Returns 0 on success.
*/
int
findnextuid(uid_t start, uid_t stop, uid_t *ret)
{
uid_t uid = start;
struct passwd *pwd;
boolean_t overflow = B_FALSE;
setpwent();
for (pwd = getpwent(); pwd != NULL; pwd = getpwent()) {
if (isreserveduid(pwd->pw_uid)) /* Skip reserved IDs */
continue;
if (pwd->pw_uid >= uid) {
if (pwd->pw_uid == stop) { /* Overflow check */
overflow = B_TRUE;
break;
}
uid = pwd->pw_uid + 1;
}
}
if (pwd == NULL && errno != 0) {
endpwent();
return (-1);
}
endpwent();
if (overflow == B_TRUE) /* Find a hole */
return (findunuseduid(start, stop, ret));
while (isreserveduid(uid) && uid < stop) /* Skip reserved IDs */
uid++;
*ret = uid;
return (0);
}
/*
* Check to see whether the uid is a reserved uid
* -- nobody, noaccess or nobody4
*/
static boolean_t
isreserveduid(uid_t uid)
{
return (uid == 60001 || uid == 60002 || uid == 65534);
}
/*
* findunuseduid() attempts to return the next valid usable id between the
* supplied upper and lower limits. Returns 0 on success.
*/
static int
findunuseduid(uid_t start, uid_t stop, uid_t *ret)
{
uid_t uid;
for (uid = start; uid <= stop; uid++) {
if (isreserveduid(uid))
continue;
if (getpwuid(uid) == NULL) {
if (errno != 0)
return (-1);
break;
}
}
if (uid > stop)
return (-1);
*ret = uid;
return (0);
}