src/mkfifo.c

   1 /* mkfifo -- make fifo's (named pipes)
   2    Copyright (C) 1990-2022 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* David MacKenzie <djm@ai.mit.edu>  */
  18
  19 #include <config.h>
  20 #include <stdio.h>
  21 #include <getopt.h>
  22 #include <sys/types.h>
  23 #include <selinux/label.h>
  24
  25 #include "system.h"
  26 #include "die.h"
  27 #include "error.h"
  28 #include "modechange.h"
  29 #include "quote.h"
  30 #include "selinux.h"
  31 #include "smack.h"
  32
  33 /* The official name of this program (e.g., no 'g' prefix).  */
  34 #define PROGRAM_NAME "mkfifo"
  35
  36 #define AUTHORS proper_name ("David MacKenzie")
  37
  38 static struct option const longopts[] =
  39 {
  40   {GETOPT_SELINUX_CONTEXT_OPTION_DECL},
  41   {"mode", required_argument, NULL, 'm'},
  42   {GETOPT_HELP_OPTION_DECL},
  43   {GETOPT_VERSION_OPTION_DECL},
  44   {NULL, 0, NULL, 0}
  45 };
  46
  47 void
  48 usage (int status)
  49 {
  50   if (status != EXIT_SUCCESS)
  51     emit_try_help ();
  52   else
  53     {
  54       printf (_("Usage: %s [OPTION]... NAME...\n"), program_name);
  55       fputs (_("\
  56 Create named pipes (FIFOs) with the given NAMEs.\n\
  57 "), stdout);
  58
  59       emit_mandatory_arg_note ();
  60
  61       fputs (_("\
  62   -m, --mode=MODE    set file permission bits to MODE, not a=rw - umask\n\
  63 "), stdout);
  64       fputs (_("\
  65   -Z                   set the SELinux security context to default type\n\
  66       --context[=CTX]  like -Z, or if CTX is specified then set the SELinux\n\
  67                          or SMACK security context to CTX\n\
  68 "), stdout);
  69       fputs (HELP_OPTION_DESCRIPTION, stdout);
  70       fputs (VERSION_OPTION_DESCRIPTION, stdout);
  71       emit_ancillary_info (PROGRAM_NAME);
  72     }
  73   exit (status);
  74 }
  75
  76 int
  77 main (int argc, char **argv)
  78 {
  79   mode_t newmode;
  80   char const *specified_mode = NULL;
  81   int exit_status = EXIT_SUCCESS;
  82   int optc;
  83   char const *scontext = NULL;
  84   struct selabel_handle *set_security_context = NULL;
  85
  86   initialize_main (&argc, &argv);
  87   set_program_name (argv[0]);
  88   setlocale (LC_ALL, "");
  89   bindtextdomain (PACKAGE, LOCALEDIR);
  90   textdomain (PACKAGE);
  91
  92   atexit (close_stdout);
  93
  94   while ((optc = getopt_long (argc, argv, "m:Z", longopts, NULL)) != -1)
  95     {
  96       switch (optc)
  97         {
  98         case 'm':
  99           specified_mode = optarg;
 100           break;
 101         case 'Z':
 102           if (is_smack_enabled ())
 103             {
 104               /* We don't yet support -Z to restore context with SMACK.  */
 105               scontext = optarg;
 106             }
 107           else if (is_selinux_enabled () > 0)
 108             {
 109               if (optarg)
 110                 scontext = optarg;
 111               else
 112                 {
 113                   set_security_context = selabel_open (SELABEL_CTX_FILE,
 114                                                        NULL, 0);
 115                   if (! set_security_context)
 116                     error (0, errno, _("warning: ignoring --context"));
 117                 }
 118             }
 119           else if (optarg)
 120             {
 121               error (0, 0,
 122                      _("warning: ignoring --context; "
 123                        "it requires an SELinux/SMACK-enabled kernel"));
 124             }
 125           break;
 126         case_GETOPT_HELP_CHAR;
 127         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 128         default:
 129           usage (EXIT_FAILURE);
 130         }
 131     }
 132
 133   if (optind == argc)
 134     {
 135       error (0, 0, _("missing operand"));
 136       usage (EXIT_FAILURE);
 137     }
 138
 139   if (scontext)
 140     {
 141       int ret = 0;
 142       if (is_smack_enabled ())
 143         ret = smack_set_label_for_self (scontext);
 144       else
 145         ret = setfscreatecon (scontext);
 146
 147       if (ret < 0)
 148         die (EXIT_FAILURE, errno,
 149              _("failed to set default file creation context to %s"),
 150              quote (scontext));
 151     }
 152
 153   newmode = MODE_RW_UGO;
 154   if (specified_mode)
 155     {
 156       mode_t umask_value;
 157       struct mode_change *change = mode_compile (specified_mode);
 158       if (!change)
 159         die (EXIT_FAILURE, 0, _("invalid mode"));
 160       umask_value = umask (0);
 161       umask (umask_value);
 162       newmode = mode_adjust (newmode, false, umask_value, change, NULL);
 163       free (change);
 164       if (newmode & ~S_IRWXUGO)
 165         die (EXIT_FAILURE, 0,
 166              _("mode must specify only file permission bits"));
 167     }
 168
 169   for (; optind < argc; ++optind)
 170     {
 171       if (set_security_context)
 172         defaultcon (set_security_context, argv[optind], S_IFIFO);
 173       if (mkfifo (argv[optind], newmode) != 0)
 174         {
 175           error (0, errno, _("cannot create fifo %s"), quoteaf (argv[optind]));
 176           exit_status = EXIT_FAILURE;
 177         }
 178       else if (specified_mode && lchmod (argv[optind], newmode) != 0)
 179         {
 180           error (0, errno, _("cannot set permissions of %s"),
 181                  quoteaf (argv[optind]));
 182           exit_status = EXIT_FAILURE;
 183         }
 184     }
 185
 186   return exit_status;
 187 }