xref: /freebsd/crypto/openssh/openbsd-compat/getgrouplist.c (revision 6b3455a7665208c366849f0b2b3bc916fb97516e)
1 /* OPENBSD ORIGINAL: lib/libc/gen/getgrouplist.c */
2 
3 /*
4  * Copyright (c) 1991, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include "includes.h"
33 
34 #ifndef HAVE_GETGROUPLIST
35 
36 #if defined(LIBC_SCCS) && !defined(lint)
37 static char rcsid[] = "$OpenBSD: getgrouplist.c,v 1.9 2003/06/25 21:16:47 deraadt Exp $";
38 #endif /* LIBC_SCCS and not lint */
39 
40 /*
41  * get credential
42  */
43 #include <sys/types.h>
44 #include <string.h>
45 #include <unistd.h>
46 #include <grp.h>
47 
48 int
49 getgrouplist(uname, agroup, groups, grpcnt)
50 	const char *uname;
51 	gid_t agroup;
52 	register gid_t *groups;
53 	int *grpcnt;
54 {
55 	register struct group *grp;
56 	register int i, ngroups;
57 	int ret, maxgroups;
58 	int bail;
59 
60 	ret = 0;
61 	ngroups = 0;
62 	maxgroups = *grpcnt;
63 
64 	/*
65 	 * install primary group
66 	 */
67 	if (ngroups >= maxgroups) {
68 		*grpcnt = ngroups;
69 		return (-1);
70 	}
71 	groups[ngroups++] = agroup;
72 
73 	/*
74 	 * Scan the group file to find additional groups.
75 	 */
76 	setgrent();
77 	while ((grp = getgrent())) {
78 		if (grp->gr_gid == agroup)
79 			continue;
80 		for (bail = 0, i = 0; bail == 0 && i < ngroups; i++)
81 			if (groups[i] == grp->gr_gid)
82 				bail = 1;
83 		if (bail)
84 			continue;
85 		for (i = 0; grp->gr_mem[i]; i++) {
86 			if (!strcmp(grp->gr_mem[i], uname)) {
87 				if (ngroups >= maxgroups) {
88 					ret = -1;
89 					goto out;
90 				}
91 				groups[ngroups++] = grp->gr_gid;
92 				break;
93 			}
94 		}
95 	}
96 out:
97 	endgrent();
98 	*grpcnt = ngroups;
99 	return (ret);
100 }
101 
102 #endif /* HAVE_GETGROUPLIST */
103