getgrouplist.c revision 1574 
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
34#if defined(LIBC_SCCS) && !defined(lint)
35static char sccsid[] = "@(#)getgrouplist.c	8.1 (Berkeley) 6/4/93";
36#endif /* LIBC_SCCS and not lint */
37
38/*
39 * get credential
40 */
41#include <sys/types.h>
42#include <string.h>
43#include <grp.h>
44
45int
46getgrouplist(uname, agroup, groups, grpcnt)
47	const char *uname;
48	int agroup;
49	register int *groups;
50	int *grpcnt;
51{
52	register struct group *grp;
53	register struct passwd *pw;
54	register int i, ngroups;
55	int ret, maxgroups;
56
57	ret = 0;
58	ngroups = 0;
59	maxgroups = *grpcnt;
60	/*
61	 * When installing primary group, duplicate it;
62	 * the first element of groups is the effective gid
63	 * and will be overwritten when a setgid file is executed.
64	 */
65	groups[ngroups++] = agroup;
66	if (maxgroups > 1)
67		groups[ngroups++] = agroup;
68	/*
69	 * Scan the group file to find additional groups.
70	 */
71	setgrent();
72	while (grp = getgrent()) {
73		if (grp->gr_gid == agroup)
74			continue;
75		if (ngroups >= maxgroups) {
76			ret = -1;
77			break;
78		}
79		for (i = 0; grp->gr_mem[i]; i++) {
80			if (!strcmp(grp->gr_mem[i], uname)) {
81				groups[ngroups++] = grp->gr_gid;
82				break;
83			}
84		}
85	}
86	endgrent();
87	*grpcnt = ngroups;
88	return (ret);
89}
90