xref: /titanic_41/usr/src/cmd/ssh/sshd/groupaccess.c (revision 7522f2fc4a704256ba53f51fc6fe14e17f45b9bd)
1 /*
2  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 /*
6  * Copyright (c) 2001 Kevin Steves.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include "includes.h"
30 RCSID("$OpenBSD: groupaccess.c,v 1.5 2002/03/04 17:27:39 stevesk Exp $");
31 
32 #include "groupaccess.h"
33 #include "xmalloc.h"
34 #include "match.h"
35 #include "log.h"
36 #include <alloca.h>
37 
38 static int ngroups, ngroups_lim;
39 static char **groups_byname;
40 
41 /*
42  * Initialize group access list for user with primary (base) and
43  * supplementary groups.  Return the number of groups in the list.
44  */
45 int
46 ga_init(const char *user, gid_t base)
47 {
48 	gid_t *groups_bygid;
49 	int i, j;
50 	struct group *gr;
51 
52 	if (ngroups_lim == 0) {
53 		/* Add one for the base gid */
54 		ngroups_lim = sysconf(_SC_NGROUPS_MAX) + 1;
55 		groups_byname = malloc(sizeof (char *) * ngroups_lim);
56 	} else if (ngroups > 0)
57 		ga_free();
58 
59 	groups_bygid = alloca(ngroups_lim * sizeof (gid_t));
60 
61 	ngroups = ngroups_lim;
62 	if (getgrouplist(user, base, groups_bygid, &ngroups) == -1)
63 		log("getgrouplist: groups list too small");
64 	for (i = 0, j = 0; i < ngroups; i++)
65 		if ((gr = getgrgid(groups_bygid[i])) != NULL)
66 			groups_byname[j++] = xstrdup(gr->gr_name);
67 	return (ngroups = j);
68 }
69 
70 /*
71  * Return 1 if one of user's groups is contained in groups.
72  * Return 0 otherwise.  Use match_pattern() for string comparison.
73  */
74 int
75 ga_match(char * const *groups, int n)
76 {
77 	int i, j;
78 
79 	for (i = 0; i < ngroups; i++)
80 		for (j = 0; j < n; j++)
81 			if (match_pattern(groups_byname[i], groups[j]))
82 				return (1);
83 	return (0);
84 }
85 
86 /*
87  * Return 1 if one of user's groups matches group_pattern list.
88  * Return 0 on negated or no match.
89  */
90 int
91 ga_match_pattern_list(const char *group_pattern)
92 {
93 	int i, found = 0;
94 	size_t len = strlen(group_pattern);
95 
96 	for (i = 0; i < ngroups; i++) {
97 		switch (match_pattern_list(groups_byname[i],
98 		    group_pattern, len, 0)) {
99 		case -1:
100 			return (0);	/* Negated match wins */
101 		case 0:
102 			continue;
103 		case 1:
104 			found = 1;
105 		}
106 	}
107 	return (found);
108 }
109 
110 /*
111  * Free memory allocated for group access list.
112  */
113 void
114 ga_free(void)
115 {
116 	int i;
117 
118 	if (ngroups > 0) {
119 		for (i = 0; i < ngroups; i++)
120 			xfree(groups_byname[i]);
121 		ngroups = 0;
122 	}
123 }
124