1 /* $NetBSD: groupaccess.c,v 1.9 2019/04/20 17:16:40 christos Exp $ */
2 /* $OpenBSD: groupaccess.c,v 1.17 2019/03/06 22:14:23 dtucker Exp $ */
3 /*
4 * Copyright (c) 2001 Kevin Steves. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include "includes.h"
28 __RCSID("$NetBSD: groupaccess.c,v 1.9 2019/04/20 17:16:40 christos Exp $");
29 #include <sys/types.h>
30
31 #include <grp.h>
32 #include <unistd.h>
33 #include <stdarg.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <limits.h>
37
38 #include "xmalloc.h"
39 #include "groupaccess.h"
40 #include "match.h"
41 #include "log.h"
42
43 static int ngroups;
44 static char *groups_byname[NGROUPS_MAX + 1]; /* +1 for base/primary group */
45
46 /*
47 * Initialize group access list for user with primary (base) and
48 * supplementary groups. Return the number of groups in the list.
49 */
50 int
ga_init(const char * user,gid_t base)51 ga_init(const char *user, gid_t base)
52 {
53 gid_t groups_bygid[NGROUPS_MAX + 1];
54 int i, j;
55 struct group *gr;
56
57 if (ngroups > 0)
58 ga_free();
59
60 ngroups = sizeof(groups_bygid) / sizeof(gid_t);
61 if (getgrouplist(user, base, groups_bygid, &ngroups) == -1)
62 logit("getgrouplist: groups list too small");
63 for (i = 0, j = 0; i < ngroups; i++)
64 if ((gr = getgrgid(groups_bygid[i])) != NULL)
65 groups_byname[j++] = xstrdup(gr->gr_name);
66 return (ngroups = j);
67 }
68
69 /*
70 * Return 1 if one of user's groups is contained in groups.
71 * Return 0 otherwise. Use match_pattern() for string comparison.
72 */
73 int
ga_match(char * const * groups,int n)74 ga_match(char * const *groups, int n)
75 {
76 int i, j;
77
78 for (i = 0; i < ngroups; i++)
79 for (j = 0; j < n; j++)
80 if (match_pattern(groups_byname[i], groups[j]))
81 return 1;
82 return 0;
83 }
84
85 /*
86 * Return 1 if one of user's groups matches group_pattern list.
87 * Return 0 on negated or no match.
88 */
89 int
ga_match_pattern_list(const char * group_pattern)90 ga_match_pattern_list(const char *group_pattern)
91 {
92 int i, found = 0;
93
94 for (i = 0; i < ngroups; i++) {
95 switch (match_usergroup_pattern_list(groups_byname[i],
96 group_pattern)) {
97 case -1:
98 return 0; /* Negated match wins */
99 case 0:
100 continue;
101 case 1:
102 found = 1;
103 }
104 }
105 return found;
106 }
107
108 /*
109 * Free memory allocated for group access list.
110 */
111 void
ga_free(void)112 ga_free(void)
113 {
114 int i;
115
116 if (ngroups > 0) {
117 for (i = 0; i < ngroups; i++)
118 free(groups_byname[i]);
119 ngroups = 0;
120 }
121 }
122