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 #include <sys/stat.h>
   8
   9
  10 static void prepare (void);
  11 #define PREPARE(argc, argv) prepare ()
  12
  13 static int do_test (void);
  14 #define TEST_FUNCTION do_test ()
  15
  16 #include "../test-skeleton.c"
  17
  18 static int dir_fd;
  19
  20 static void
  21 prepare (void)
  22 {
  23 #if _POSIX_CHOWN_RESTRICTED == 0
  24   if (pathconf (test_dir, _PC_CHOWN_RESTRICTED) != 0)
  25 #endif
  26     {
  27       uid_t uid = getuid ();
  28       if (uid != 0)
  29         {
  30           puts ("need root privileges");
  31           exit (0);
  32         }
  33     }
  34
  35   size_t test_dir_len = strlen (test_dir);
  36   static const char dir_name[] = "/tst-fchownat.XXXXXX";
  37
  38   size_t dirbuflen = test_dir_len + sizeof (dir_name);
  39   char *dirbuf = malloc (dirbuflen);
  40   if (dirbuf == NULL)
  41     {
  42       puts ("out of memory");
  43       exit (1);
  44     }
  45
  46   snprintf (dirbuf, dirbuflen, "%s%s", test_dir, dir_name);
  47   if (mkdtemp (dirbuf) == NULL)
  48     {
  49       puts ("cannot create temporary directory");
  50       exit (1);
  51     }
  52
  53   add_temp_file (dirbuf);
  54
  55   dir_fd = open (dirbuf, O_RDONLY | O_DIRECTORY);
  56   if (dir_fd == -1)
  57     {
  58       puts ("cannot open directory");
  59       exit (1);
  60     }
  61 }
  62
  63
  64 static int
  65 do_test (void)
  66 {
  67   /* fdopendir takes over the descriptor, make a copy.  */
  68   int dupfd = dup (dir_fd);
  69   if (dupfd == -1)
  70     {
  71       puts ("dup failed");
  72       return 1;
  73     }
  74   if (lseek (dupfd, 0, SEEK_SET) != 0)
  75     {
  76       puts ("1st lseek failed");
  77       return 1;
  78     }
  79
  80   /* The directory should be empty safe the . and .. files.  */
  81   DIR *dir = fdopendir (dupfd);
  82   if (dir == NULL)
  83     {
  84       puts ("fdopendir failed");
  85       return 1;
  86     }
  87   struct dirent64 *d;
  88   while ((d = readdir64 (dir)) != NULL)
  89     if (strcmp (d->d_name, ".") != 0 && strcmp (d->d_name, "..") != 0)
  90       {
  91         printf ("temp directory contains file \"%s\"\n", d->d_name);
  92         return 1;
  93       }
  94   closedir (dir);
  95
  96   /* Try to create a file.  */
  97   int fd = openat (dir_fd, "some-file", O_CREAT|O_RDWR|O_EXCL, 0666);
  98   if (fd == -1)
  99     {
 100       if (errno == ENOSYS)
 101         {
 102           puts ("*at functions not supported");
 103           return 0;
 104         }
 105
 106       puts ("file creation failed");
 107       return 1;
 108     }
 109   write (fd, "hello", 5);
 110   puts ("file created");
 111
 112   struct stat64 st1;
 113   if (fstat64 (fd, &st1) != 0)
 114     {
 115       puts ("fstat64 failed");
 116       return 1;
 117     }
 118
 119   /* Before closing the file, try using this file descriptor to open
 120      another file.  This must fail.  */
 121   if (fchownat (fd, "some-file", 1, 1, 0) != -1)
 122     {
 123       puts ("fchownat using descriptor for normal file worked");
 124       return 1;
 125     }
 126   if (errno != ENOTDIR)
 127     {
 128       puts ("\
 129 error for fchownat using descriptor for normal file not ENOTDIR ");
 130       return 1;
 131     }
 132
 133   close (fd);
 134
 135   if (fchownat (dir_fd, "some-file", st1.st_uid + 1, st1.st_gid + 1, 0) != 0)
 136     {
 137       puts ("fchownat failed");
 138       return 1;
 139     }
 140
 141   struct stat64 st2;
 142   if (fstatat64 (dir_fd, "some-file", &st2, 0) != 0)
 143     {
 144       puts ("fstatat64 failed");
 145       return 1;
 146     }
 147
 148   if (st1.st_uid + 1 != st2.st_uid || st1.st_gid + 1 != st2.st_gid)
 149     {
 150       puts ("owner change failed");
 151       return 1;
 152     }
 153
 154   if (unlinkat (dir_fd, "some-file", 0) != 0)
 155     {
 156       puts ("unlinkat failed");
 157       return 1;
 158     }
 159
 160   /* Create a file descriptor which is closed again right away.  */
 161   int dir_fd2 = dup (dir_fd);
 162   if (dir_fd2 == -1)
 163     {
 164       puts ("dup failed");
 165       return 1;
 166     }
 167   close (dir_fd2);
 168
 169   if (fchownat (dir_fd2, "some-file", 1, 1, 0) != -1)
 170     {
 171       puts ("fchownat using closed descriptor worked");
 172       return 1;
 173     }
 174   if (errno != EBADF)
 175     {
 176       puts ("error for fchownat using closed descriptor not EBADF ");
 177       return 1;
 178     }
 179
 180   close (dir_fd);
 181
 182   if (fchownat (-1, "some-file", 1, 1, 0) != -1)
 183     {
 184       puts ("fchownat using invalid descriptor worked");
 185       return 1;
 186     }
 187   if (errno != EBADF)
 188     {
 189       puts ("error for fchownat using invalid descriptor not EBADF ");
 190       return 1;
 191     }
 192
 193   return 0;
 194 }