1 /* $NetBSD: getgrouplist.c,v 1.16 2003/02/16 01:22:44 elric Exp $ */ 2 3 /* 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)getgrouplist.c 8.2 (Berkeley) 12/8/94"; 40 #else 41 __RCSID("$NetBSD: getgrouplist.c,v 1.16 2003/02/16 01:22:44 elric Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 /* 46 * get credential 47 */ 48 #include "namespace.h" 49 #include <sys/param.h> 50 51 #include <assert.h> 52 #include <grp.h> 53 #include <string.h> 54 #include <unistd.h> 55 56 #ifdef __weak_alias 57 __weak_alias(getgrouplist,_getgrouplist) 58 #endif 59 60 /* 61 * _getgrent_user() is a libc-private function defined in getgrent.c which 62 * use because certain name service types such as Hesiod lookup grouplists 63 * by username rather than just iterating over the list of groups. 64 */ 65 struct group *_getgrent_user(const char *); 66 67 int 68 getgrouplist(uname, agroup, groups, grpcnt) 69 const char *uname; 70 gid_t agroup; 71 gid_t *groups; 72 int *grpcnt; 73 { 74 struct group *grp; 75 int i, ngroups; 76 int ret, maxgroups; 77 78 _DIAGASSERT(uname != NULL); 79 _DIAGASSERT(groups != NULL); 80 _DIAGASSERT(grpcnt != NULL); 81 82 ret = 0; 83 ngroups = 0; 84 maxgroups = *grpcnt; 85 86 /* 87 * install primary group 88 */ 89 if (ngroups < maxgroups) 90 groups[ngroups] = agroup; 91 else 92 ret = -1; 93 ngroups++; 94 95 /* 96 * Scan the group file to find additional groups. 97 */ 98 setgrent(); 99 nextgroup: 100 while ((grp = _getgrent_user(uname)) != NULL) { 101 if (grp->gr_gid == agroup) 102 continue; 103 for (i = 0; i < MIN(ngroups, maxgroups); i++) { 104 if (grp->gr_gid == groups[i]) 105 goto nextgroup; 106 } 107 if (ngroups < maxgroups) 108 groups[ngroups] = grp->gr_gid; 109 else 110 ret = -1; 111 ngroups++; 112 } 113 endgrent(); 114 *grpcnt = ngroups; 115 return (ret); 116 } 117