1 /* $OpenBSD: groupaccess.c,v 1.18 2024/11/04 21:59:15 jca 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 28 #include <grp.h> 29 #include <unistd.h> 30 #include <stdarg.h> 31 #include <stdlib.h> 32 #include <string.h> 33 #include <limits.h> 34 35 #include "xmalloc.h" 36 #include "groupaccess.h" 37 #include "match.h" 38 #include "log.h" 39 40 static int ngroups; 41 static char *groups_byname[NGROUPS_MAX + 1]; /* +1 for base/primary group */ 42 43 /* 44 * Initialize group access list for user with primary (base) and 45 * supplementary groups. Return the number of groups in the list. 46 */ 47 int 48 ga_init(const char *user, gid_t base) 49 { 50 gid_t groups_bygid[NGROUPS_MAX + 1]; 51 int i, j, maxgroups; 52 struct group *gr; 53 54 if (ngroups > 0) 55 ga_free(); 56 57 maxgroups = ngroups = sizeof(groups_bygid) / sizeof(gid_t); 58 if (getgrouplist(user, base, groups_bygid, &ngroups) == -1) { 59 logit("getgrouplist: groups list too small"); 60 /* Truncate group list */ 61 ngroups = maxgroups; 62 } 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 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 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 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