testcases/kernel/syscalls/fchmod/fchmod05.c

   1 /*
   2  *
   3  *   Copyright (c) International Business Machines  Corp., 2001
   4  *
   5  *   This program is free software;  you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation; either version 2 of the License, or
   8  *   (at your option) any later version.
   9  *
  10  *   This program is distributed in the hope that it will be useful,
  11  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  13  *   the GNU General Public License for more details.
  14  *
  15  *   You should have received a copy of the GNU General Public License
  16  *   along with this program;  if not, write to the Free Software
  17  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18  */
  19
  20 /*
  21  * Test Name: fchmod05
  22  *
  23  * Test Description:
  24  *  Verify that, fchmod(2) will succeed to change the mode of a directory
  25  *  but fails to set the setgid bit on it if invoked by non-root (uid != 0)
  26  *  process with the following constraints,
  27  *      - the process is the owner of the directory.
  28  *      - the effective group ID or one of the supplementary group ID's of the
  29  *        process is not equal to the group ID of the directory.
  30  *
  31  * Expected Result:
  32  *  fchmod() should return value 0 on success and though succeeds to change
  33  *  the mode of a directory but fails to set setgid bit on it.
  34  *
  35  * Algorithm:
  36  *  Setup:
  37  *   Setup signal handling.
  38  *   Create temporary directory.
  39  *   Pause for SIGUSR1 if option specified.
  40  *
  41  *  Test:
  42  *   Loop if the proper options are given.
  43  *   Execute system call
  44  *   Check return code, if system call failed (return=-1)
  45  *      Log the errno and Issue a FAIL message.
  46  *   Otherwise,
  47  *      Verify the Functionality of system call
  48  *      if successful,
  49  *              Issue Functionality-Pass message.
  50  *      Otherwise,
  51  *              Issue Functionality-Fail message.
  52  *  Cleanup:
  53  *   Print errno log and/or timing stats if options given
  54  *   Delete the temporary directory created.
  55  *
  56  * Usage:  <for command-line>
  57  *  fchmod05 [-c n] [-f] [-i n] [-I x] [-P x] [-t]
  58  *     where,  -c n : Run n copies concurrently.
  59  *             -f   : Turn off functionality Testing.
  60  *             -i n : Execute test n times.
  61  *             -I x : Execute test for x seconds.
  62  *             -P x : Pause for x seconds between iterations.
  63  *             -t   : Turn on syscall timing.
  64  *
  65  * HISTORY
  66  *      07/2001 Ported by Wayne Boyer
  67  *
  68  * RESTRICTIONS:
  69  *  This test should be run by 'non-super-user' only.
  70  *
  71  */
  72
  73 #ifndef _GNU_SOURCE
  74 # define _GNU_SOURCE
  75 #endif
  76
  77 #include <stdio.h>
  78 #include <stdlib.h>
  79 #include <sys/types.h>
  80 #include <sys/stat.h>
  81 #include <sys/fcntl.h>
  82 #include <errno.h>
  83 #include <string.h>
  84 #include <signal.h>
  85 #include <unistd.h>
  86 #include <grp.h>
  87 #include <pwd.h>
  88
  89 #include "test.h"
  90 #include "usctest.h"
  91
  92 #define MODE_RWX        S_IRWXU | S_IRWXG | S_IRWXO
  93 #define PERMS           043777
  94 #define TESTDIR         "testdir"
  95
  96 int fd;                         /* file descriptor for test directory */
  97 char *TCID="fchmod05";          /* Test program identifier.    */
  98 int TST_TOTAL=1;                /* Total number of test cases. */
  99 extern int Tst_count;           /* Test Case counter for tst_* routines */
 100
 101 void setup();                   /* Main setup function for test */
 102 void cleanup();                 /* Main cleanup function for test */
 103
 104 int
 105 main(int ac, char **av)
 106 {
 107         struct stat stat_buf;   /* stat struct */
 108         int lc;                 /* loop counter */
 109         char *msg;              /* message returned from parse_opts */
 110         mode_t dir_mode;        /* mode permissions set on test directory */
 111
 112         /* Parse standard options given to run the test. */
 113         msg = parse_opts(ac, av, (option_t *) NULL, NULL);
 114         if (msg != (char *) NULL) {
 115                 tst_brkm(TBROK, NULL, "OPTION PARSING ERROR - %s", msg);
 116                 tst_exit();
 117         }
 118
 119         /* Perform global setup for test */
 120         setup();
 121
 122         /* Check looping state if -i option given */
 123         for (lc = 0; TEST_LOOPING(lc); lc++) {
 124                 /* Reset Tst_count in case we are looping. */
 125                 Tst_count = 0;
 126
 127                 /*
 128                  * Call fchmod(2) with mode argument
 129                  * to set setgid bit on TESTDIR.
 130                  */
 131
 132                 TEST(fchmod(fd, PERMS));
 133
 134                 /* check return code of fchmod(2) */
 135                 if (TEST_RETURN == -1) {
 136                         tst_resm(TFAIL, "fchmod(%d, %#o) Failed, errno=%d : %s",
 137                                  fd, PERMS, TEST_ERRNO, strerror(TEST_ERRNO));
 138                         continue;
 139                 }
 140                 /*
 141                  * Perform functional verification if test
 142                  * executed without (-f) option.
 143                  */
 144                 if (STD_FUNCTIONAL_TEST) {
 145                         /*
 146                          * Get the directory information using
 147                          * fstat(2).
 148                          */
 149                         if (fstat(fd, &stat_buf) < 0) {
 150                                  tst_brkm(TFAIL, cleanup,
 151                                           "fstat(2) of %s failed, errno:%d",
 152                                           TESTDIR, TEST_ERRNO);
 153                         }
 154                         dir_mode = stat_buf.st_mode;
 155                         if (PERMS != dir_mode) {
 156                                 tst_resm(TFAIL, "%s: Incorrect modes 0%03o, "
 157                                          "Expected 0%03o",
 158                                          TESTDIR, PERMS, MODE_RWX);
 159                         } else {
 160                                 tst_resm(TPASS, "Functionality of fchmod(%d, "
 161                                          "%#o) successful", fd, PERMS);
 162                         }
 163                 } else {
 164                         tst_resm(TPASS, "call succeeded");
 165                 }
 166         }       /* End for TEST_LOOPING */
 167
 168         /* Call cleanup() to undo setup done for the test. */
 169         cleanup();
 170
 171         /*NOTREACHED*/
 172         return(0);
 173 }       /* End main */
 174
 175 /*
 176  * void
 177  * setup() - performs all ONE TIME setup for this test.
 178  *  Create a temporary directory and cd to it.
 179  *  Create a test directory under temporary directory.
 180  *  Invoke setuid to root program to modify group ownership
 181  *  on test directory.
 182  *  Open the test directory for reading.
 183  */
 184 void
 185 setup()
 186 {
 187         char *test_home;                /* variable to hold TESTHOME env */
 188    struct passwd* nobody_u;
 189    struct group* bin_group;
 190
 191         /* capture signals */
 192         tst_sig(FORK, DEF_HANDLER, cleanup);
 193
 194         /* Check that the test process id is not super/root  */
 195         if (geteuid() != 0) {
 196                 tst_brkm(TBROK, NULL, "Must be super/root for this test!");
 197                 tst_exit();
 198         }
 199
 200         test_home = get_current_dir_name();
 201
 202         /* Pause if that option was specified */
 203         TEST_PAUSE;
 204
 205         /* make a temp directory and cd to it */
 206         tst_tmpdir();
 207
 208    nobody_u=getpwnam("nobody");
 209    if(!nobody_u)
 210      tst_brkm(TBROK, cleanup,
 211               "Couldn't find uid of nobody: %s", strerror(errno));
 212
 213    bin_group=getgrnam("bin");
 214    if(!bin_group)
 215      tst_brkm(TBROK, cleanup,
 216               "Couldn't find gid of bin: %s", strerror(errno));
 217
 218    // yield root and change to nobody:bin
 219    seteuid(nobody_u->pw_uid);
 220    setegid(bin_group->gr_gid);
 221         /*
 222          * Create a test directory under temporary directory with specified
 223          * mode permissions and change the gid of test directory to that of
 224          * guest user.
 225          */
 226         if (mkdir(TESTDIR, MODE_RWX) < 0) {
 227                 tst_brkm(TBROK, cleanup, "mkdir(2) of %s failed", TESTDIR);
 228         }
 229
 230    // change to nobody:nobody
 231    setegid(nobody_u->pw_gid);
 232
 233         /* Open the test directory for reading */
 234         if ((fd = open(TESTDIR, O_RDONLY)) == -1) {
 235                 tst_brkm(TBROK, cleanup,
 236                          "open(%s, O_RDONLY) failed, errno=%d : %s",
 237                          TESTDIR, errno, strerror(errno));
 238         }
 239 }       /* End setup() */
 240
 241
 242 /*
 243  * void
 244  * cleanup() - performs all ONE TIME cleanup for this test at
 245  *              completion or premature exit.
 246  *  Close the test directory opened in the setup().
 247  *  Remove the test directory and temporary directory created in
 248  *  in the setup().
 249  */
 250 void
 251 cleanup()
 252 {
 253         /*
 254          * print timing stats if that option was specified.
 255          */
 256         TEST_CLEANUP;
 257
 258         /* Close the test directory opened in the setup() */
 259         if (close(fd) == -1) {
 260                 tst_brkm(TBROK, NULL,
 261                          "close(%s) Failed, errno=%d : %s",
 262                          TESTDIR, errno, strerror(errno));
 263         }
 264
 265         /* Remove tmp dir and all files in it */
 266         tst_rmdir();
 267
 268         /* exit with return code appropriate for results */
 269         tst_exit();
 270 }       /* End cleanup() */