openbsd-compat/getgrouplist.c

   1 /*      $OpenBSD: getgrouplist.c,v 1.12 2005/08/08 08:05:34 espie Exp $ */
   2 /*
   3  * Copyright (c) 1991, 1993
   4  *      The Regents of the University of California.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. Neither the name of the University nor the names of its contributors
  15  *    may be used to endorse or promote products derived from this software
  16  *    without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  */
  30
  31 /* OPENBSD ORIGINAL: lib/libc/gen/getgrouplist.c */
  32
  33 #include "includes.h"
  34
  35 #ifndef HAVE_GETGROUPLIST
  36
  37 /*
  38  * get credential
  39  */
  40 #include <sys/types.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43 #include <grp.h>
  44
  45 int
  46 getgrouplist(const char *uname, gid_t agroup, gid_t *groups, int *grpcnt)
  47 {
  48         struct group *grp;
  49         int i, ngroups;
  50         int ret, maxgroups;
  51         int bail;
  52
  53         ret = 0;
  54         ngroups = 0;
  55         maxgroups = *grpcnt;
  56
  57         /*
  58          * install primary group
  59          */
  60         if (ngroups >= maxgroups) {
  61                 *grpcnt = ngroups;
  62                 return (-1);
  63         }
  64         groups[ngroups++] = agroup;
  65
  66         /*
  67          * Scan the group file to find additional groups.
  68          */
  69         setgrent();
  70         while ((grp = getgrent())) {
  71                 if (grp->gr_gid == agroup)
  72                         continue;
  73                 for (bail = 0, i = 0; bail == 0 && i < ngroups; i++)
  74                         if (groups[i] == grp->gr_gid)
  75                                 bail = 1;
  76                 if (bail)
  77                         continue;
  78                 for (i = 0; grp->gr_mem[i]; i++) {
  79                         if (!strcmp(grp->gr_mem[i], uname)) {
  80                                 if (ngroups >= maxgroups) {
  81                                         ret = -1;
  82                                         goto out;
  83                                 }
  84                                 groups[ngroups++] = grp->gr_gid;
  85                                 break;
  86                         }
  87                 }
  88         }
  89 out:
  90         endgrent();
  91         *grpcnt = ngroups;
  92         return (ret);
  93 }
  94
  95 #endif /* HAVE_GETGROUPLIST */