1 /* $OpenBSD: groupaccess.c,v 1.16 2015/05/04 06:10:48 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 30 #include <grp.h> 31 #include <unistd.h> 32 #include <stdarg.h> 33 #include <stdlib.h> 34 #include <string.h> 35 #include <limits.h> 36 37 #include "xmalloc.h" 38 #include "groupaccess.h" 39 #include "match.h" 40 #include "log.h" 41 42 static int ngroups; 43 static char **groups_byname; 44 45 /* 46 * Initialize group access list for user with primary (base) and 47 * supplementary groups. Return the number of groups in the list. 48 */ 49 int 50 ga_init(const char *user, gid_t base) 51 { 52 gid_t *groups_bygid; 53 int i, j; 54 struct group *gr; 55 56 if (ngroups > 0) 57 ga_free(); 58 59 ngroups = NGROUPS_MAX; 60 #if defined(HAVE_SYSCONF) && defined(_SC_NGROUPS_MAX) 61 ngroups = MAX(NGROUPS_MAX, sysconf(_SC_NGROUPS_MAX)); 62 #endif 63 64 groups_bygid = xcalloc(ngroups, sizeof(*groups_bygid)); 65 groups_byname = xcalloc(ngroups, sizeof(*groups_byname)); 66 67 if (getgrouplist(user, base, groups_bygid, &ngroups) == -1) 68 logit("getgrouplist: groups list too small"); 69 for (i = 0, j = 0; i < ngroups; i++) 70 if ((gr = getgrgid(groups_bygid[i])) != NULL) 71 groups_byname[j++] = xstrdup(gr->gr_name); 72 free(groups_bygid); 73 return (ngroups = j); 74 } 75 76 /* 77 * Return 1 if one of user's groups is contained in groups. 78 * Return 0 otherwise. Use match_pattern() for string comparison. 79 */ 80 int 81 ga_match(char * const *groups, int n) 82 { 83 int i, j; 84 85 for (i = 0; i < ngroups; i++) 86 for (j = 0; j < n; j++) 87 if (match_pattern(groups_byname[i], groups[j])) 88 return 1; 89 return 0; 90 } 91 92 /* 93 * Return 1 if one of user's groups matches group_pattern list. 94 * Return 0 on negated or no match. 95 */ 96 int 97 ga_match_pattern_list(const char *group_pattern) 98 { 99 int i, found = 0; 100 101 for (i = 0; i < ngroups; i++) { 102 switch (match_pattern_list(groups_byname[i], group_pattern, 0)) { 103 case -1: 104 return 0; /* Negated match wins */ 105 case 0: 106 continue; 107 case 1: 108 found = 1; 109 } 110 } 111 return found; 112 } 113 114 /* 115 * Free memory allocated for group access list. 116 */ 117 void 118 ga_free(void) 119 { 120 int i; 121 122 if (ngroups > 0) { 123 for (i = 0; i < ngroups; i++) 124 free(groups_byname[i]); 125 ngroups = 0; 126 free(groups_byname); 127 } 128 } 129