io/tst-fchownat.c

   1 #include <dirent.h>
   2 #include <fcntl.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <unistd.h>
   7
   8
   9 static void prepare (void);
  10 #define PREPARE(argc, argv) prepare ()
  11
  12 static int do_test (void);
  13 #define TEST_FUNCTION do_test ()
  14
  15 #include "../test-skeleton.c"
  16
  17 static int dir_fd;
  18
  19 static void
  20 prepare (void)
  21 {
  22 #if _POSIX_CHOWN_RESTRICTED == 0
  23   if (pathconf (test_dir, _PC_CHOWN_RESTRICTED) != 0)
  24 #endif
  25     {
  26       uid_t uid = getuid ();
  27       if (uid != 0)
  28         {
  29           puts ("need root privileges");
  30           exit (0);
  31         }
  32     }
  33
  34   size_t test_dir_len = strlen (test_dir);
  35   static const char dir_name[] = "/tst-fchownat.XXXXXX";
  36
  37   size_t dirbuflen = test_dir_len + sizeof (dir_name);
  38   char *dirbuf = malloc (dirbuflen);
  39   if (dirbuf == NULL)
  40     {
  41       puts ("out of memory");
  42       exit (1);
  43     }
  44
  45   snprintf (dirbuf, dirbuflen, "%s%s", test_dir, dir_name);
  46   if (mkdtemp (dirbuf) == NULL)
  47     {
  48       puts ("cannot create temporary directory");
  49       exit (1);
  50     }
  51
  52   add_temp_file (dirbuf);
  53
  54   dir_fd = open (dirbuf, O_RDONLY | O_DIRECTORY);
  55   if (dir_fd == -1)
  56     {
  57       puts ("cannot open directory");
  58       exit (1);
  59     }
  60 }
  61
  62
  63 static int
  64 do_test (void)
  65 {
  66   /* fdopendir takes over the descriptor, make a copy.  */
  67   int dupfd = dup (dir_fd);
  68   if (dupfd == -1)
  69     {
  70       puts ("dup failed");
  71       return 1;
  72     }
  73   if (lseek (dupfd, 0, SEEK_SET) != 0)
  74     {
  75       puts ("1st lseek failed");
  76       return 1;
  77     }
  78
  79   /* The directory should be empty safe the . and .. files.  */
  80   DIR *dir = fdopendir (dupfd);
  81   if (dir == NULL)
  82     {
  83       puts ("fdopendir failed");
  84       return 1;
  85     }
  86   struct dirent64 *d;
  87   while ((d = readdir64 (dir)) != NULL)
  88     if (strcmp (d->d_name, ".") != 0 && strcmp (d->d_name, "..") != 0)
  89       {
  90         printf ("temp directory contains file \"%s\"\n", d->d_name);
  91         return 1;
  92       }
  93   closedir (dir);
  94
  95   /* Try to create a file.  */
  96   int fd = openat (dir_fd, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666);
  97   if (fd == -1)
  98     {
  99       if (errno == ENOSYS)
 100         {
 101           puts ("*at functions not supported");
 102           return 0;
 103         }
 104
 105       puts ("file creation failed");
 106       return 1;
 107     }
 108   write (fd, "hello", 5);
 109   puts ("file created");
 110
 111   struct stat64 st1;
 112   if (fstat64 (fd, &st1) != 0)
 113     {
 114       puts ("fstat64 failed");
 115       return 1;
 116     }
 117
 118   /* Before closing the file, try using this file descriptor to open
 119      another file.  This must fail.  */
 120   if (fchownat (fd, "some-file", 1, 1, 0) != -1)
 121     {
 122       puts ("fchownat using descriptor for normal file worked");
 123       return 1;
 124     }
 125   if (errno != ENOTDIR)
 126     {
 127       puts ("\
 128 error for fchownat using descriptor for normal file not ENOTDIR ");
 129       return 1;
 130     }
 131
 132   close (fd);
 133
 134   if (fchownat (dir_fd, "some-file", st1.st_uid + 1, st1.st_gid + 1, 0) != 0)
 135     {
 136       puts ("fchownat failed");
 137       return 1;
 138     }
 139
 140   struct stat64 st2;
 141   if (fstatat64 (dir_fd, "some-file", &st2, 0) != 0)
 142     {
 143       puts ("fstatat64 failed");
 144       return 1;
 145     }
 146
 147   if (st1.st_uid + 1 != st2.st_uid || st1.st_gid + 1 != st2.st_gid)
 148     {
 149       puts ("owner change failed");
 150       return 1;
 151     }
 152
 153   if (unlinkat (dir_fd, "some-file", 0) != 0)
 154     {
 155       puts ("unlinkat failed");
 156       return 1;
 157     }
 158
 159   /* Create a file descriptor which is closed again right away.  */
 160   int dir_fd2 = dup (dir_fd);
 161   if (dir_fd2 == -1)
 162     {
 163       puts ("dup failed");
 164       return 1;
 165     }
 166   close (dir_fd2);
 167
 168   if (fchownat (dir_fd2, "some-file", 1, 1, 0) != -1)
 169     {
 170       puts ("fchownat using closed descriptor worked");
 171       return 1;
 172     }
 173   if (errno != EBADF)
 174     {
 175       puts ("error for fchownat using closed descriptor not EBADF ");
 176       return 1;
 177     }
 178
 179   close (dir_fd);
 180
 181   if (fchownat (-1, "some-file", 1, 1, 0) != -1)
 182     {
 183       puts ("fchownat using invalid descriptor worked");
 184       return 1;
 185     }
 186   if (errno != EBADF)
 187     {
 188       puts ("error for fchownat using invalid descriptor not EBADF ");
 189       return 1;
 190     }
 191
 192   return 0;
 193 }