1 /* $OpenBSD: groupaccess.c,v 1.17 2019/03/06 22:14:23 dtucker 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; 52 struct group *gr; 53 54 if (ngroups > 0) 55 ga_free(); 56 57 ngroups = sizeof(groups_bygid) / sizeof(gid_t); 58 if (getgrouplist(user, base, groups_bygid, &ngroups) == -1) 59 logit("getgrouplist: groups list too small"); 60 for (i = 0, j = 0; i < ngroups; i++) 61 if ((gr = getgrgid(groups_bygid[i])) != NULL) 62 groups_byname[j++] = xstrdup(gr->gr_name); 63 return (ngroups = j); 64 } 65 66 /* 67 * Return 1 if one of user's groups is contained in groups. 68 * Return 0 otherwise. Use match_pattern() for string comparison. 69 */ 70 int 71 ga_match(char * const *groups, int n) 72 { 73 int i, j; 74 75 for (i = 0; i < ngroups; i++) 76 for (j = 0; j < n; j++) 77 if (match_pattern(groups_byname[i], groups[j])) 78 return 1; 79 return 0; 80 } 81 82 /* 83 * Return 1 if one of user's groups matches group_pattern list. 84 * Return 0 on negated or no match. 85 */ 86 int 87 ga_match_pattern_list(const char *group_pattern) 88 { 89 int i, found = 0; 90 91 for (i = 0; i < ngroups; i++) { 92 switch (match_usergroup_pattern_list(groups_byname[i], 93 group_pattern)) { 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 109 ga_free(void) 110 { 111 int i; 112 113 if (ngroups > 0) { 114 for (i = 0; i < ngroups; i++) 115 free(groups_byname[i]); 116 ngroups = 0; 117 } 118 } 119