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 42static int ngroups; 43static 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 */ 49int 50ga_init(const char *user, gid_t base) 51{ 52 gid_t *groups_bygid; 53 int i, j, retry = 0; 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 while (getgrouplist(user, base, groups_bygid, &ngroups) == -1) { 66 if (retry++ > 0) 67 fatal("getgrouplist: groups list too small"); 68 groups_bygid = xreallocarray(groups_bygid, ngroups, 69 sizeof(*groups_bygid)); 70 } 71 groups_byname = xcalloc(ngroups, sizeof(*groups_byname)); 72 73 for (i = 0, j = 0; i < ngroups; i++) 74 if ((gr = getgrgid(groups_bygid[i])) != NULL) 75 groups_byname[j++] = xstrdup(gr->gr_name); 76 free(groups_bygid); 77 return (ngroups = j); 78} 79 80/* 81 * Return 1 if one of user's groups is contained in groups. 82 * Return 0 otherwise. Use match_pattern() for string comparison. 83 */ 84int 85ga_match(char * const *groups, int n) 86{ 87 int i, j; 88 89 for (i = 0; i < ngroups; i++) 90 for (j = 0; j < n; j++) 91 if (match_pattern(groups_byname[i], groups[j])) 92 return 1; 93 return 0; 94} 95 96/* 97 * Return 1 if one of user's groups matches group_pattern list. 98 * Return 0 on negated or no match. 99 */ 100int 101ga_match_pattern_list(const char *group_pattern) 102{ 103 int i, found = 0; 104 105 for (i = 0; i < ngroups; i++) { 106 switch (match_pattern_list(groups_byname[i], group_pattern, 0)) { 107 case -1: 108 return 0; /* Negated match wins */ 109 case 0: 110 continue; 111 case 1: 112 found = 1; 113 } 114 } 115 return found; 116} 117 118/* 119 * Free memory allocated for group access list. 120 */ 121void 122ga_free(void) 123{ 124 int i; 125 126 if (ngroups > 0) { 127 for (i = 0; i < ngroups; i++) 128 free(groups_byname[i]); 129 ngroups = 0; 130 free(groups_byname); 131 groups_byname = NULL; 132 } 133} 134