openbsd-compat/getgrouplist.c

   1 /* OPENBSD ORIGINAL: lib/libc/gen/getgrouplist.c */
   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. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include "includes.h"
  33
  34 #ifndef HAVE_GETGROUPLIST
  35
  36 #if defined(LIBC_SCCS) && !defined(lint)
  37 static char rcsid[] = "$OpenBSD: getgrouplist.c,v 1.9 2003/06/25 21:16:47 deraadt Exp $";
  38 #endif /* LIBC_SCCS and not lint */
  39
  40 /*
  41  * get credential
  42  */
  43 #include <sys/types.h>
  44 #include <string.h>
  45 #include <unistd.h>
  46 #include <grp.h>
  47
  48 int
  49 getgrouplist(uname, agroup, groups, grpcnt)
  50         const char *uname;
  51         gid_t agroup;
  52         register gid_t *groups;
  53         int *grpcnt;
  54 {
  55         register struct group *grp;
  56         register int i, ngroups;
  57         int ret, maxgroups;
  58         int bail;
  59
  60         ret = 0;
  61         ngroups = 0;
  62         maxgroups = *grpcnt;
  63
  64         /*
  65          * install primary group
  66          */
  67         if (ngroups >= maxgroups) {
  68                 *grpcnt = ngroups;
  69                 return (-1);
  70         }
  71         groups[ngroups++] = agroup;
  72
  73         /*
  74          * Scan the group file to find additional groups.
  75          */
  76         setgrent();
  77         while ((grp = getgrent())) {
  78                 if (grp->gr_gid == agroup)
  79                         continue;
  80                 for (bail = 0, i = 0; bail == 0 && i < ngroups; i++)
  81                         if (groups[i] == grp->gr_gid)
  82                                 bail = 1;
  83                 if (bail)
  84                         continue;
  85                 for (i = 0; grp->gr_mem[i]; i++) {
  86                         if (!strcmp(grp->gr_mem[i], uname)) {
  87                                 if (ngroups >= maxgroups) {
  88                                         ret = -1;
  89                                         goto out;
  90                                 }
  91                                 groups[ngroups++] = grp->gr_gid;
  92                                 break;
  93                         }
  94                 }
  95         }
  96 out:
  97         endgrent();
  98         *grpcnt = ngroups;
  99         return (ret);
 100 }
 101
 102 #endif /* HAVE_GETGROUPLIST */