tests/test-passfd.c

   1 /* Test of passing file descriptors.
   2    Copyright (C) 2011-2024 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 #include <config.h>
  18
  19 #include "passfd.h"
  20
  21 #include <errno.h>
  22 #include <fcntl.h>
  23 #include <signal.h>
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <unistd.h>
  27 #include <sys/types.h>
  28 #include <sys/socket.h>
  29 #include <sys/stat.h>
  30 #include <sys/wait.h>
  31
  32 #include "macros.h"
  33
  34 int
  35 main ()
  36 {
  37 #if defined __CYGWIN__
  38   /* Cygwin does not support file-descriptor passing: As on Cygwin 3.5.3,
  39      the only cmsg_type that winsup/cygwin/fhandler/socket_unix.cc handles
  40      is SCM_CREDENTIALS.  Not SCM_RIGHTS.  */
  41   return 90;
  42 #elif HAVE_SOCKETPAIR
  43   int pair[2];
  44   int ret;
  45   pid_t pid;
  46   int status;
  47   int fdnull;
  48   int fd;
  49   struct stat st;
  50
  51 # if HAVE_DECL_ALARM
  52   /* Avoid hanging on failure.  */
  53   int alarm_value = 5;
  54   signal (SIGALRM, SIG_DFL);
  55   alarm (alarm_value);
  56 # endif
  57
  58   fdnull = open ("/dev/null", O_RDWR);
  59   if (fdnull < 0)
  60     {
  61       perror ("Could not open /dev/null");
  62       return 1;
  63     }
  64
  65   ret = socketpair (AF_UNIX, SOCK_STREAM, 0, pair);
  66   if (ret < 0)
  67     {
  68       perror ("socket pair failed");
  69       return 2;
  70     }
  71
  72   pid = fork ();
  73   if (pid == -1)
  74     {
  75       perror ("fork");
  76       return 3;
  77     }
  78   if (pid == 0)
  79     {
  80       ret = sendfd (pair[1], fdnull);
  81       if (ret == -1)
  82         {
  83           perror ("sendfd");
  84           return 64;
  85         }
  86       return 0;
  87     }
  88   /* father */
  89   else
  90     {
  91       ASSERT (close (pair[1]) == 0);
  92       fd = recvfd (pair[0], 0);
  93       if (fd == -1)
  94         {
  95           perror ("recvfd");
  96           return 16;
  97         }
  98       ret = waitpid (pid, &status, 0);
  99       if (ret == -1)
 100         {
 101           perror ("waitpid");
 102           return 17;
 103         }
 104       ASSERT (ret == pid);
 105
 106       if (!WIFEXITED (status))
 107         {
 108           fprintf (stderr, "Child does not normally exit\n");
 109           return 65;
 110         }
 111       ret = WEXITSTATUS (status);
 112       if (ret != 0)
 113         {
 114           fprintf (stderr, "Send fd fail\n");
 115           return ret;
 116         }
 117
 118       /* try to stat new fd */
 119       ret = fstat (fd, &st);
 120       if (ret < 0)
 121         {
 122           perror ("fstat");
 123           return 80;
 124         }
 125
 126       /* Check behavior when sender no longer around */
 127       errno = 0;
 128       fd = recvfd (pair[0], 0);
 129       ASSERT (fd == -1);
 130       ASSERT (errno == ENOTCONN);
 131
 132       return test_exit_status;
 133     }
 134 #else
 135   errno = 0;
 136   ASSERT(sendfd (0, 0) == -1);
 137   ASSERT(errno == ENOSYS);
 138
 139   errno = 0;
 140   ASSERT(recvfd (0, 0) == -1);
 141   ASSERT(errno == ENOSYS);
 142
 143   if (test_exit_status != EXIT_SUCCESS)
 144     return test_exit_status;
 145   fputs ("skipping test: socketpair not supported on this system\n",
 146          stderr);
 147   return 77;
 148 #endif
 149 }