xref: /dragonfly/lib/libc/gen/getgrouplist.c (revision e8364298)
1 /*
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * @(#)getgrouplist.c	8.2 (Berkeley) 12/8/94
34  * $DragonFly: src/lib/libc/gen/getgrouplist.c,v 1.4 2004/06/19 18:55:47 joerg Exp $
35  */
36 
37 /*
38  * get credential
39  */
40 #include <sys/types.h>
41 #include <string.h>
42 #include <grp.h>
43 
44 int
45 getgrouplist(uname, agroup, groups, grpcnt)
46 	const char *uname;
47 	int agroup;
48 	int *groups;
49 	int *grpcnt;
50 {
51 	struct group *grp;
52 	int i, ngroups;
53 	int ret, maxgroups;
54 
55 	ret = 0;
56 	ngroups = 0;
57 	maxgroups = *grpcnt;
58 	/*
59 	 * When installing primary group, duplicate it;
60 	 * the first element of groups is the effective gid
61 	 * and will be overwritten when a setgid file is executed.
62 	 */
63 	groups[ngroups++] = agroup;
64 	if (maxgroups > 1)
65 		groups[ngroups++] = agroup;
66 	/*
67 	 * Scan the group file to find additional groups.
68 	 */
69 	setgrent();
70 	while (grp = getgrent()) {
71 		for (i = 0; i < ngroups; i++) {
72 			if (grp->gr_gid == groups[i])
73 				goto skip;
74 		}
75 		for (i = 0; grp->gr_mem[i]; i++) {
76 			if (!strcmp(grp->gr_mem[i], uname)) {
77 				if (ngroups >= maxgroups) {
78 					ret = -1;
79 					break;
80 				}
81 				groups[ngroups++] = grp->gr_gid;
82 				break;
83 			}
84 		}
85 skip:
86 		;
87 	}
88 	endgrent();
89 	*grpcnt = ngroups;
90 	return (ret);
91 }
92