contrib/sendmail-8.14/test/t_setreuid.c

   1 /*
   2  * Copyright (c) 2001 Sendmail, Inc. and its suppliers.
   3  *      All rights reserved.
   4  *
   5  * By using this file, you agree to the terms and conditions set
   6  * forth in the LICENSE file which can be found at the top level of
   7  * the sendmail distribution.
   8  *
   9  */
  10
  11 /*
  12 **  This program checks to see if your version of setreuid works.
  13 **  Compile it, make it set-user-ID root, and run it as yourself (NOT as
  14 **  root).  If it won't compile or outputs any MAYDAY messages, don't
  15 **  define HASSETREUID in conf.h.
  16 **
  17 **  Compilation is trivial -- just "cc t_setreuid.c".  Make it set-user-ID,
  18 **  root and then execute it as a non-root user.
  19 */
  20
  21 #include <sys/types.h>
  22 #include <unistd.h>
  23 #include <stdio.h>
  24
  25 #ifndef lint
  26 static char id[] = "@(#)$Id: t_setreuid.c,v 8.9 2001/10/12 03:04:46 gshapiro Exp $";
  27 #endif /* ! lint */
  28
  29 #ifdef __hpux
  30 # define setreuid(r, e) setresuid(r, e, -1)
  31 #endif /* __hpux */
  32
  33 static void
  34 printuids(str, r, e)
  35         char *str;
  36         uid_t r, e;
  37 {
  38         printf("%s (should be %d/%d): r/euid=%d/%d\n", str, (int) r, (int) e,
  39                (int) getuid(), (int) geteuid());
  40 }
  41
  42 int
  43 main(argc, argv)
  44         int argc;
  45         char **argv;
  46 {
  47         int fail = 0;
  48         uid_t realuid = getuid();
  49
  50         printuids("initial uids", realuid, 0);
  51
  52         if (geteuid() != 0)
  53         {
  54                 printf("SETUP ERROR: re-run set-user-ID root\n");
  55                 exit(1);
  56         }
  57
  58         if (getuid() == 0)
  59         {
  60                 printf("SETUP ERROR: must be run by a non-root user\n");
  61                 exit(1);
  62         }
  63
  64         if (setreuid(0, 1) < 0)
  65         {
  66                 fail++;
  67                 printf("setreuid(0, 1) failure\n");
  68         }
  69         printuids("after setreuid(0, 1)", 0, 1);
  70
  71         if (getuid() != 0)
  72         {
  73                 fail++;
  74                 printf("MAYDAY!  Wrong real uid\n");
  75         }
  76
  77         if (geteuid() != 1)
  78         {
  79                 fail++;
  80                 printf("MAYDAY!  Wrong effective uid\n");
  81         }
  82
  83         /* do activity here */
  84
  85         if (setreuid(-1, 0) < 0)
  86         {
  87                 fail++;
  88                 printf("setreuid(-1, 0) failure\n");
  89         }
  90         printuids("after setreuid(-1, 0)", 0, 0);
  91         if (setreuid(realuid, 0) < 0)
  92         {
  93                 fail++;
  94                 printf("setreuid(%d, 0) failure\n", (int) realuid);
  95         }
  96         printuids("after setreuid(realuid, 0)", realuid, 0);
  97
  98         if (geteuid() != 0)
  99         {
 100                 fail++;
 101                 printf("MAYDAY!  Wrong effective uid\n");
 102         }
 103         if (getuid() != realuid)
 104         {
 105                 fail++;
 106                 printf("MAYDAY!  Wrong real uid\n");
 107         }
 108         printf("\n");
 109
 110         if (setreuid(0, 2) < 0)
 111         {
 112                 fail++;
 113                 printf("setreuid(0, 2) failure\n");
 114         }
 115         printuids("after setreuid(0, 2)", 0, 2);
 116
 117         if (geteuid() != 2)
 118         {
 119                 fail++;
 120                 printf("MAYDAY!  Wrong effective uid\n");
 121         }
 122
 123         if (getuid() != 0)
 124         {
 125                 fail++;
 126                 printf("MAYDAY!  Wrong real uid\n");
 127         }
 128
 129         /* do activity here */
 130
 131         if (setreuid(-1, 0) < 0)
 132         {
 133                 fail++;
 134                 printf("setreuid(-1, 0) failure\n");
 135         }
 136         printuids("after setreuid(-1, 0)", 0, 0);
 137         if (setreuid(realuid, 0) < 0)
 138         {
 139                 fail++;
 140                 printf("setreuid(%d, 0) failure\n", (int) realuid);
 141         }
 142         printuids("after setreuid(realuid, 0)", realuid, 0);
 143
 144         if (geteuid() != 0)
 145         {
 146                 fail++;
 147                 printf("MAYDAY!  Wrong effective uid\n");
 148         }
 149         if (getuid() != realuid)
 150         {
 151                 fail++;
 152                 printf("MAYDAY!  Wrong real uid\n");
 153         }
 154
 155         if (fail)
 156         {
 157                 printf("\nThis system cannot use setreuid\n");
 158                 exit(1);
 159         }
 160
 161         printf("\nIt is safe to define HASSETREUID on this system\n");
 162         exit(0);
 163 }