xref: /dragonfly/crypto/openssh/groupaccess.c (revision 82730a9c)
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 "includes.h"
27 
28 #include <sys/types.h>
29 #include <sys/param.h>
30 
31 #include <grp.h>
32 #include <unistd.h>
33 #include <stdarg.h>
34 #include <string.h>
35 
36 #include "xmalloc.h"
37 #include "groupaccess.h"
38 #include "match.h"
39 #include "log.h"
40 
41 static int ngroups;
42 static char **groups_byname;
43 
44 /*
45  * Initialize group access list for user with primary (base) and
46  * supplementary groups.  Return the number of groups in the list.
47  */
48 int
49 ga_init(const char *user, gid_t base)
50 {
51 	gid_t *groups_bygid;
52 	int i, j;
53 	struct group *gr;
54 
55 	if (ngroups > 0)
56 		ga_free();
57 
58 	ngroups = NGROUPS_MAX;
59 #if defined(HAVE_SYSCONF) && defined(_SC_NGROUPS_MAX)
60 	ngroups = MAX(NGROUPS_MAX, sysconf(_SC_NGROUPS_MAX));
61 #endif
62 
63 	groups_bygid = xcalloc(ngroups, sizeof(*groups_bygid));
64 	groups_byname = xcalloc(ngroups, sizeof(*groups_byname));
65 
66 	if (getgrouplist(user, base, groups_bygid, &ngroups) == -1)
67 		logit("getgrouplist: groups list too small");
68 	for (i = 0, j = 0; i < ngroups; i++)
69 		if ((gr = getgrgid(groups_bygid[i])) != NULL)
70 			groups_byname[j++] = xstrdup(gr->gr_name);
71 	xfree(groups_bygid);
72 	return (ngroups = j);
73 }
74 
75 /*
76  * Return 1 if one of user's groups is contained in groups.
77  * Return 0 otherwise.  Use match_pattern() for string comparison.
78  */
79 int
80 ga_match(char * const *groups, int n)
81 {
82 	int i, j;
83 
84 	for (i = 0; i < ngroups; i++)
85 		for (j = 0; j < n; j++)
86 			if (match_pattern(groups_byname[i], groups[j]))
87 				return 1;
88 	return 0;
89 }
90 
91 /*
92  * Return 1 if one of user's groups matches group_pattern list.
93  * Return 0 on negated or no match.
94  */
95 int
96 ga_match_pattern_list(const char *group_pattern)
97 {
98 	int i, found = 0;
99 	size_t len = strlen(group_pattern);
100 
101 	for (i = 0; i < ngroups; i++) {
102 		switch (match_pattern_list(groups_byname[i],
103 		    group_pattern, len, 0)) {
104 		case -1:
105 			return 0;	/* Negated match wins */
106 		case 0:
107 			continue;
108 		case 1:
109 			found = 1;
110 		}
111 	}
112 	return found;
113 }
114 
115 /*
116  * Free memory allocated for group access list.
117  */
118 void
119 ga_free(void)
120 {
121 	int i;
122 
123 	if (ngroups > 0) {
124 		for (i = 0; i < ngroups; i++)
125 			xfree(groups_byname[i]);
126 		ngroups = 0;
127 		xfree(groups_byname);
128 	}
129 }
130