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-rw-r--r--stdlib/tst-secure-getenv.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/stdlib/tst-secure-getenv.c b/stdlib/tst-secure-getenv.c
new file mode 100644
index 0000000000..76d8de6ed4
--- /dev/null
+++ b/stdlib/tst-secure-getenv.c
@@ -0,0 +1,250 @@
+/* Copyright (C) 2012 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+/* Test that secure_getenv works by invoking the test as a SGID
+ program with a group ID from the supplementary group list. This
+ test can fail spuriously if the user is not a member of a suitable
+ supplementary group. */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+static char MAGIC_ARGUMENT[] = "run-actual-test";
+#define MAGIC_STATUS 19
+
+static const char *test_dir;
+
+/* Return a GID which is not our current GID, but is present in the
+ supplementary group list. */
+static gid_t
+choose_gid (void)
+{
+ const int count = 64;
+ gid_t groups[count];
+ int ret = getgroups (count, groups);
+ if (ret < 0)
+ {
+ perror ("getgroups");
+ exit (1);
+ }
+ gid_t current = getgid ();
+ for (int i = 0; i < ret; ++i)
+ {
+ if (groups[i] != current)
+ return groups[i];
+ }
+ return 0;
+}
+
+
+/* Copies the executable into a restricted directory, so that we can
+ safely make it SGID with the TARGET group ID. Then runs the
+ executable. */
+static int
+run_executable_sgid (gid_t target)
+{
+ char *dirname = 0;
+ char *execname = 0;
+ int infd = -1;
+ int outfd = -1;
+ int ret = -1;
+ if (asprintf (&dirname, "%s/secure-getenv.%jd",
+ test_dir, (intmax_t) getpid ()) < 0)
+ {
+ perror ("asprintf");
+ goto err;
+ }
+ if (mkdir (dirname, 0700) < 0)
+ {
+ perror ("mkdir");
+ goto err;
+ }
+ if (asprintf (&execname, "%s/bin", dirname) < 0)
+ {
+ perror ("asprintf");
+ goto err;
+ }
+ infd = open ("/proc/self/exe", O_RDONLY);
+ if (infd < 0)
+ {
+ perror ("open");
+ goto err;
+ }
+ outfd = open (execname, O_WRONLY | O_CREAT | O_EXCL, 0700);
+ if (outfd < 0)
+ {
+ perror ("open");
+ goto err;
+ }
+ char buf[4096];
+ for (;;)
+ {
+ ssize_t rdcount = read (infd, buf, sizeof (buf));
+ if (rdcount < 0)
+ {
+ perror ("read");
+ goto err;
+ }
+ if (rdcount == 0)
+ break;
+ char *p = buf;
+ char *end = buf + rdcount;
+ while (p != end)
+ {
+ ssize_t wrcount = write (outfd, buf, end - p);
+ if (wrcount == 0)
+ errno = ENOSPC;
+ if (wrcount <= 0)
+ {
+ perror ("write");
+ goto err;
+ }
+ p += wrcount;
+ }
+ }
+ if (fchown (outfd, getuid (), target) < 0)
+ {
+ perror ("fchown");
+ goto err;
+ }
+ if (fchmod (outfd, 02750) < 0)
+ {
+ perror ("fchmod");
+ goto err;
+ }
+ if (close (outfd) < 0)
+ {
+ perror ("close");
+ goto err;
+ }
+ if (close (infd) < 0)
+ {
+ perror ("close");
+ goto err;
+ }
+
+ int kid = fork ();
+ if (kid < 0)
+ {
+ perror ("fork");
+ goto err;
+ }
+ if (kid == 0)
+ {
+ /* Child process. */
+ char *args[] = { execname, MAGIC_ARGUMENT, NULL };
+ execve (execname, args, environ);
+ perror ("execve");
+ _exit (1);
+ }
+ int status;
+ if (waitpid (kid, &status, 0) < 0)
+ {
+ perror ("waitpid");
+ goto err;
+ }
+ if (!WIFEXITED (status) || WEXITSTATUS (status) != MAGIC_STATUS)
+ {
+ fprintf (stderr, "Unexpected exit status %d from child process\n",
+ status);
+ goto err;
+ }
+ ret = 0;
+
+err:
+ if (outfd >= 0)
+ close (outfd);
+ if (infd >= 0)
+ close (infd);
+ if (execname)
+ {
+ unlink (execname);
+ free (execname);
+ }
+ if (dirname)
+ {
+ rmdir (dirname);
+ free (dirname);
+ }
+ return ret;
+}
+
+static int
+do_test (void)
+{
+ if (getenv ("PATH") == NULL)
+ {
+ fprintf (stderr, "PATH not set\n");
+ exit (1);
+ }
+ if (secure_getenv ("PATH") == NULL)
+ {
+ fprintf (stderr, "PATH not set according to secure_getenv\n");
+ exit (1);
+ }
+ if (strcmp (getenv ("PATH"), secure_getenv ("PATH")) != 0)
+ {
+ fprintf (stderr, "PATH mismatch (%s, %s)\n",
+ getenv ("PATH"), secure_getenv ("PATH"));
+ exit (1);
+ }
+
+ gid_t target = choose_gid ();
+ if (target == 0)
+ {
+ fprintf (stderr, "Could not find a suitable GID user %jd\n",
+ (intmax_t) getuid ());
+ exit (1);
+ }
+ return run_executable_sgid (target);
+}
+
+static void
+alternative_main (int argc, char **argv)
+{
+ if (argc == 2 && strcmp (argv[1], MAGIC_ARGUMENT) == 0)
+ {
+ if (getgid () == getegid ())
+ {
+ fprintf (stderr, "SGID failed: GID and EGID match (%jd)\n",
+ (intmax_t) getgid ());
+ exit (2);
+ }
+ if (getenv ("PATH") == NULL)
+ {
+ fprintf (stderr, "PATH variable not present\n");
+ exit (3);
+ }
+ if (secure_getenv ("PATH") != NULL)
+ {
+ fprintf (stderr, "PATH variable not filtered out\n");
+ exit (4);
+ }
+ exit (MAGIC_STATUS);
+ }
+}
+
+#define PREPARE(argc, argv) alternative_main(argc, argv)
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"