xref: /onnv-gate/usr/src/cmd/oamuser/user/uid.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright (c) 1997-2001 by Sun Microsystems, Inc.
24*0Sstevel@tonic-gate  * All rights reserved.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28*0Sstevel@tonic-gate /*	  All Rights Reserved  	*/
29*0Sstevel@tonic-gate 
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"	/* SVr4.0 1.5 */
32*0Sstevel@tonic-gate 
33*0Sstevel@tonic-gate #include <sys/types.h>
34*0Sstevel@tonic-gate #include <stdio.h>
35*0Sstevel@tonic-gate #include <userdefs.h>
36*0Sstevel@tonic-gate #include <pwd.h>
37*0Sstevel@tonic-gate 
38*0Sstevel@tonic-gate #include <sys/param.h>
39*0Sstevel@tonic-gate #ifndef	MAXUID
40*0Sstevel@tonic-gate #include <limits.h>
41*0Sstevel@tonic-gate #ifdef UID_MAX
42*0Sstevel@tonic-gate #define	MAXUID	UID_MAX
43*0Sstevel@tonic-gate #else
44*0Sstevel@tonic-gate #define	MAXUID	60000
45*0Sstevel@tonic-gate #endif
46*0Sstevel@tonic-gate #endif
47*0Sstevel@tonic-gate 
48*0Sstevel@tonic-gate static uid_t getrangeboundid(uid_t start, uid_t stop);
49*0Sstevel@tonic-gate static int isreserveduid(uid_t uid);
50*0Sstevel@tonic-gate 
51*0Sstevel@tonic-gate /*
52*0Sstevel@tonic-gate  * Find the highest uid currently in use and return it. If the highest unused
53*0Sstevel@tonic-gate  * uid is MAXUID, then attempt to find a hole in the range. If there are no
54*0Sstevel@tonic-gate  * more unused uids, then return -1.
55*0Sstevel@tonic-gate  */
56*0Sstevel@tonic-gate uid_t
findnextuid(void)57*0Sstevel@tonic-gate findnextuid(void)
58*0Sstevel@tonic-gate {
59*0Sstevel@tonic-gate 	uid_t uid = DEFRID + 1;
60*0Sstevel@tonic-gate 	struct passwd *pwd;
61*0Sstevel@tonic-gate 	uchar_t overflow = 0;
62*0Sstevel@tonic-gate 
63*0Sstevel@tonic-gate 	setpwent();
64*0Sstevel@tonic-gate 	for (pwd = getpwent(); pwd != NULL; pwd = getpwent()) {
65*0Sstevel@tonic-gate 		if (isreserveduid(pwd->pw_uid))		/* Skip reserved IDs */
66*0Sstevel@tonic-gate 			continue;
67*0Sstevel@tonic-gate 		if (pwd->pw_uid >= uid) {
68*0Sstevel@tonic-gate 			if (pwd->pw_uid == MAXUID) {	/* Overflow check */
69*0Sstevel@tonic-gate 				overflow = 1;
70*0Sstevel@tonic-gate 				break;
71*0Sstevel@tonic-gate 			}
72*0Sstevel@tonic-gate 			uid = pwd->pw_uid + 1;
73*0Sstevel@tonic-gate 			while (isreserveduid(uid) &&
74*0Sstevel@tonic-gate 			    uid < MAXUID) {		/* Skip reserved IDs */
75*0Sstevel@tonic-gate 				uid++;
76*0Sstevel@tonic-gate 			}
77*0Sstevel@tonic-gate 		}
78*0Sstevel@tonic-gate 	}
79*0Sstevel@tonic-gate 	endpwent();
80*0Sstevel@tonic-gate 	if (overflow == 1)				/* Find a hole */
81*0Sstevel@tonic-gate 		return (getrangeboundid(DEFRID + 1, MAXUID));
82*0Sstevel@tonic-gate 	return (uid);
83*0Sstevel@tonic-gate }
84*0Sstevel@tonic-gate 
85*0Sstevel@tonic-gate /*
86*0Sstevel@tonic-gate  * Check to see that the uid is a reserved uid
87*0Sstevel@tonic-gate  * -- nobody, noaccess or nobody4
88*0Sstevel@tonic-gate  */
89*0Sstevel@tonic-gate static int
isreserveduid(uid_t uid)90*0Sstevel@tonic-gate isreserveduid(uid_t uid)
91*0Sstevel@tonic-gate {
92*0Sstevel@tonic-gate 	return (uid == 60001 || uid == 60002 || uid == 65534);
93*0Sstevel@tonic-gate }
94*0Sstevel@tonic-gate 
95*0Sstevel@tonic-gate 
96*0Sstevel@tonic-gate /*
97*0Sstevel@tonic-gate  * getrangeboundid() attempts to return the next valid usable id between the
98*0Sstevel@tonic-gate  * supplied upper and lower limits. If these limits exceed the system
99*0Sstevel@tonic-gate  * boundaries of DEFRID +1 and MAXUID (lower and upper bound respectively),
100*0Sstevel@tonic-gate  * then they are ignored and DEFRID + 1 and MAXUID are used.
101*0Sstevel@tonic-gate  *
102*0Sstevel@tonic-gate  * Returns a valid uid_t between DEFRID +1 and MAXUID, -1 is returned on fail
103*0Sstevel@tonic-gate  */
104*0Sstevel@tonic-gate static uid_t
getrangeboundid(uid_t start,uid_t stop)105*0Sstevel@tonic-gate getrangeboundid(uid_t start, uid_t stop)
106*0Sstevel@tonic-gate {
107*0Sstevel@tonic-gate 	uid_t low = (start <= DEFRID) ? DEFRID + 1 : start;
108*0Sstevel@tonic-gate 	uid_t high = (stop < MAXUID) ? stop : MAXUID;
109*0Sstevel@tonic-gate 	uid_t uid;
110*0Sstevel@tonic-gate 
111*0Sstevel@tonic-gate 	for (uid = low; uid <= high; uid++) {
112*0Sstevel@tonic-gate 		if (isreserveduid(uid))
113*0Sstevel@tonic-gate 			continue;
114*0Sstevel@tonic-gate 		if (getpwuid(uid) == NULL)
115*0Sstevel@tonic-gate 			break;
116*0Sstevel@tonic-gate 	}
117*0Sstevel@tonic-gate 	return ((uid > high) ? -1 : uid);
118*0Sstevel@tonic-gate }
119