1 /* $OpenBSD: groupaccess.c,v 1.13 2008/07/04 03:44:59 djm Exp $ */
2 /*
3 * Copyright (c) 2001 Kevin Steves. 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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include <sys/types.h>
27 #include <sys/param.h>
28
29 #include <grp.h>
30 #include <unistd.h>
31 #include <stdarg.h>
32 #include <string.h>
33
34 #include "xmalloc.h"
35 #include "groupaccess.h"
36 #include "match.h"
37 #include "log.h"
38
39 static int ngroups;
40 static char *groups_byname[NGROUPS_MAX + 1]; /* +1 for base/primary group */
41
42 /*
43 * Initialize group access list for user with primary (base) and
44 * supplementary groups. Return the number of groups in the list.
45 */
46 int
ga_init(const char * user,gid_t base)47 ga_init(const char *user, gid_t base)
48 {
49 gid_t groups_bygid[NGROUPS_MAX + 1];
50 int i, j;
51 struct group *gr;
52
53 if (ngroups > 0)
54 ga_free();
55
56 ngroups = sizeof(groups_bygid) / sizeof(gid_t);
57 if (getgrouplist(user, base, groups_bygid, &ngroups) == -1)
58 logit("getgrouplist: groups list too small");
59 for (i = 0, j = 0; i < ngroups; i++)
60 if ((gr = getgrgid(groups_bygid[i])) != NULL)
61 groups_byname[j++] = xstrdup(gr->gr_name);
62 return (ngroups = j);
63 }
64
65 /*
66 * Return 1 if one of user's groups is contained in groups.
67 * Return 0 otherwise. Use match_pattern() for string comparison.
68 */
69 int
ga_match(char * const * groups,int n)70 ga_match(char * const *groups, int n)
71 {
72 int i, j;
73
74 for (i = 0; i < ngroups; i++)
75 for (j = 0; j < n; j++)
76 if (match_pattern(groups_byname[i], groups[j]))
77 return 1;
78 return 0;
79 }
80
81 /*
82 * Return 1 if one of user's groups matches group_pattern list.
83 * Return 0 on negated or no match.
84 */
85 int
ga_match_pattern_list(const char * group_pattern)86 ga_match_pattern_list(const char *group_pattern)
87 {
88 int i, found = 0;
89 size_t len = strlen(group_pattern);
90
91 for (i = 0; i < ngroups; i++) {
92 switch (match_pattern_list(groups_byname[i],
93 group_pattern, len, 0)) {
94 case -1:
95 return 0; /* Negated match wins */
96 case 0:
97 continue;
98 case 1:
99 found = 1;
100 }
101 }
102 return found;
103 }
104
105 /*
106 * Free memory allocated for group access list.
107 */
108 void
ga_free(void)109 ga_free(void)
110 {
111 int i;
112
113 if (ngroups > 0) {
114 for (i = 0; i < ngroups; i++)
115 xfree(groups_byname[i]);
116 ngroups = 0;
117 }
118 }
119