Home | History | Annotate | Download | only in setuid 
      1 /******************************************************************************
      2  * Copyright (c) Kerlabs 2008.                                                *
      3  * Copyright (c) International Business Machines  Corp., 2008                 *
      4  *  Created by Renaud Lottiaux                                                *
      5  *                                                                            *
      6  * This program is free software;  you can redistribute it and/or modify      *
      7  * it under the terms of the GNU General Public License as published by       *
      8  * the Free Software Foundation; either version 2 of the License, or          *
      9  * (at your option) any later version.                                        *
     10  *                                                                            *
     11  * This program is distributed in the hope that it will be useful,            *
     12  * but WITHOUT ANY WARRANTY;  without even the implied warranty of            *
     13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See                  *
     14  * the GNU General Public License for more details.                           *
     15  *                                                                            *
     16  * You should have received a copy of the GNU General Public License          *
     17  * along with this program;  if not, write to the Free Software Foundation,   *
     18  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA           *
     19  *****************************************************************************/
     20 
     21 /*
     22  * Check if setuid behaves correctly with file permissions. The test creates a
     23  * file as ROOT with permissions 0644, does a setuid and then tries to open the
     24  * file with RDWR permissions. The same test is done in a fork to check if new
     25  * UIDs are correctly passed to the son.
     26  */
     27 
     28 #include <errno.h>
     29 #include <pwd.h>
     30 #include <sys/types.h>
     31 #include <sys/stat.h>
     32 #include <sys/wait.h>
     33 #include <fcntl.h>
     34 #include <unistd.h>
     35 
     36 #include "test.h"
     37 #include "safe_macros.h"
     38 #include "compat_16.h"
     39 
     40 char *TCID = "setuid04";
     41 int TST_TOTAL = 1;
     42 
     43 static char nobody_uid[] = "nobody";
     44 static char testfile[] = "setuid04_testfile";
     45 static struct passwd *ltpuser;
     46 
     47 static int fd = -1;
     48 
     49 static void setup(void);
     50 static void cleanup(void);
     51 static void do_master_child(void);
     52 
     53 int main(int ac, char **av)
     54 {
     55 	pid_t pid;
     56 	int status;
     57 
     58 	tst_parse_opts(ac, av, NULL, NULL);
     59 
     60 	setup();
     61 
     62 	pid = FORK_OR_VFORK();
     63 	if (pid < 0)
     64 		tst_brkm(TBROK, cleanup, "Fork failed");
     65 
     66 	if (pid == 0) {
     67 		do_master_child();
     68 	} else {
     69 		waitpid(pid, &status, 0);
     70 		if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0))
     71 			tst_resm(WEXITSTATUS(status),
     72 				 "son process exits with error");
     73 	}
     74 
     75 	cleanup();
     76 	tst_exit();
     77 }
     78 
     79 static void do_master_child(void)
     80 {
     81 	int lc;
     82 	int pid;
     83 	int status;
     84 
     85 	if (SETUID(NULL, ltpuser->pw_uid) == -1) {
     86 		tst_brkm(TBROK, NULL,
     87 			 "setuid failed to set the effective uid to %d",
     88 			 ltpuser->pw_uid);
     89 	}
     90 
     91 	for (lc = 0; TEST_LOOPING(lc); lc++) {
     92 		int tst_fd;
     93 
     94 		tst_count = 0;
     95 
     96 		TEST(tst_fd = open(testfile, O_RDWR));
     97 
     98 		if (TEST_RETURN != -1) {
     99 			tst_resm(TFAIL, "call succeeded unexpectedly");
    100 			close(tst_fd);
    101 		}
    102 
    103 		if (TEST_ERRNO == EACCES) {
    104 			tst_resm(TPASS, "open returned errno EACCES");
    105 		} else {
    106 			tst_resm(TFAIL, "open returned unexpected errno - %d",
    107 				 TEST_ERRNO);
    108 			continue;
    109 		}
    110 
    111 		pid = FORK_OR_VFORK();
    112 		if (pid < 0)
    113 			tst_brkm(TBROK, NULL, "Fork failed");
    114 
    115 		if (pid == 0) {
    116 			int tst_fd2;
    117 
    118 			/* Test to open the file in son process */
    119 			TEST(tst_fd2 = open(testfile, O_RDWR));
    120 
    121 			if (TEST_RETURN != -1) {
    122 				tst_resm(TFAIL, "call succeeded unexpectedly");
    123 				close(tst_fd2);
    124 			}
    125 
    126 			if (TEST_ERRNO == EACCES) {
    127 				tst_resm(TPASS, "open returned errno EACCES");
    128 			} else {
    129 				tst_resm(TFAIL,
    130 					 "open returned unexpected errno - %d",
    131 					 TEST_ERRNO);
    132 			}
    133 			tst_exit();
    134 		} else {
    135 			/* Wait for son completion */
    136 			waitpid(pid, &status, 0);
    137 			if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0))
    138 				exit(WEXITSTATUS(status));
    139 		}
    140 	}
    141 	tst_exit();
    142 }
    143 
    144 static void setup(void)
    145 {
    146 	tst_require_root();
    147 
    148 	ltpuser = getpwnam(nobody_uid);
    149 
    150 	if (ltpuser == NULL)
    151 		tst_brkm(TBROK, cleanup, "getpwnam failed for user id %s",
    152 			nobody_uid);
    153 
    154 	UID16_CHECK(ltpuser->pw_uid, setuid, cleanup);
    155 
    156 	tst_tmpdir();
    157 
    158 	/* Create test file */
    159 	fd = SAFE_OPEN(cleanup, testfile, O_CREAT | O_RDWR, 0644);
    160 
    161 	tst_sig(FORK, DEF_HANDLER, cleanup);
    162 
    163 	TEST_PAUSE;
    164 }
    165 
    166 static void cleanup(void)
    167 {
    168 	close(fd);
    169 	tst_rmdir();
    170 }
    171