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-rw-r--r--src/regress/noexec/check_noexec.c203
1 files changed, 203 insertions, 0 deletions
diff --git a/src/regress/noexec/check_noexec.c b/src/regress/noexec/check_noexec.c
new file mode 100644
index 0000000..e83f420
--- /dev/null
+++ b/src/regress/noexec/check_noexec.c
@@ -0,0 +1,203 @@
+/*
+ * Copyright (c) 2016 Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <config.h>
+
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# include "compat/stdbool.h"
+#endif /* HAVE_STDBOOL_H */
+#ifdef HAVE_STRING_H
+# include <string.h>
+#endif /* HAVE_STRING_H */
+#ifdef HAVE_STRINGS_H
+# include <strings.h>
+#endif /* HAVE_STRINGS_H */
+#ifdef HAVE_WORDEXP_H
+# include <wordexp.h>
+#endif
+#include <signal.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+
+#include "sudo_compat.h"
+#include "sudo_fatal.h"
+#include "sudo_util.h"
+#include "sudo_exec.h"
+
+__dso_public int main(int argc, char *argv[], char *envp[]);
+
+static bool
+report_status(int status, const char *what)
+{
+ bool ret = false;
+
+ /* system() returns -1 for exec failure. */
+ if (status == -1) {
+ printf("%s: OK (%s)\n", getprogname(), what);
+ return true;
+ }
+
+ /* check exit value, expecting 127 for failure */
+ if (WIFEXITED(status)) {
+ int exitval = WEXITSTATUS(status);
+ if (exitval == 127) {
+ printf("%s: OK (%s)\n", getprogname(), what);
+ ret = true;
+ } else {
+ printf("%s: FAIL (%s) [%d]\n", getprogname(), what, exitval);
+ }
+ } else if (WIFSIGNALED(status)) {
+ printf("%s: FAIL (%s) [signal %d]\n", getprogname(), what,
+ WTERMSIG(status));
+ } else {
+ /* should not happen */
+ printf("%s: FAIL (%s) [status %d]\n", getprogname(), what, status);
+ }
+
+ return ret;
+}
+
+static int
+try_execl(void)
+{
+ pid_t child, pid;
+ int status;
+
+ child = fork();
+ switch (child) {
+ case -1:
+ sudo_fatal_nodebug("fork");
+ case 0:
+ /* child */
+ /* Try to exec /bin/true, else exit with value 127. */
+ execl("/bin/true", "true", (char *)0);
+ _exit(127);
+ default:
+ /* parent */
+ do {
+ pid = waitpid(child, &status, 0);
+ } while (pid == -1 && errno == EINTR);
+ if (pid == -1)
+ sudo_fatal_nodebug("waitpid");
+
+ if (report_status(status, "execl"))
+ return 0;
+ return 1;
+ }
+}
+
+static int
+try_system(void)
+{
+ int status;
+
+ /* Try to run /bin/true, system() returns 127 on exec failure. */
+ status = system("/bin/true > /dev/null 2>&1");
+
+ if (report_status(status, "system"))
+ return 0;
+ return 1;
+}
+
+#ifdef HAVE_WORDEXP_H
+static int
+try_wordexp(void)
+{
+ wordexp_t we;
+ int rc, ret = 1;
+
+ /*
+ * sudo_noexec.so prevents command substitution via the WRDE_NOCMD flag
+ * where possible.
+ */
+ rc = wordexp("$(/bin/echo foo)", &we, 0);
+ switch (rc) {
+ case -1:
+ /* sudo's wordexp() wrapper returns -1 if RTLD_NEXT is not supported. */
+ case 127:
+ /* Solaris 10 wordexp() returns 127 for execve() failure. */
+#ifdef WRDE_ERRNO
+ case WRDE_ERRNO:
+ /* Solaris 11 wordexp() returns WRDE_ERRNO for execve() failure. */
+#endif
+ printf("%s: OK (wordexp) [%d]\n", getprogname(), rc);
+ ret = 0;
+ break;
+ case WRDE_SYNTAX:
+ /* FreeBSD returns WRDE_SYNTAX if it can't write to the shell process */
+ printf("%s: OK (wordexp) [WRDE_SYNTAX]\n", getprogname());
+ ret = 0;
+ break;
+ case WRDE_CMDSUB:
+ printf("%s: OK (wordexp) [WRDE_CMDSUB]\n", getprogname());
+ ret = 0;
+ break;
+ case 0:
+ /*
+ * On HP-UX 11.00 we don't seem to be able to add WRDE_NOCMD
+ * but the execve() wrapper prevents the command substitution.
+ */
+ if (we.we_wordc == 0) {
+ printf("%s: OK (wordexp) [%d]\n", getprogname(), rc);
+ wordfree(&we);
+ ret = 0;
+ break;
+ }
+ wordfree(&we);
+ /* FALLTHROUGH */
+ default:
+ printf("%s: FAIL (wordexp) [%d]\n", getprogname(), rc);
+ break;
+ }
+ return ret;
+}
+#endif
+
+int
+main(int argc, char *argv[], char *envp[])
+{
+ int errors = 0;
+
+ initprogname(argc > 0 ? argv[0] : "check_noexec");
+
+ if (argc != 2) {
+ fprintf(stderr, "usage: %s regress | /path/to/sudo_noexec.so\n", getprogname());
+ exit(1);
+ }
+
+ /* Disable execution for post-exec and re-exec ourself. */
+ if (strcmp(argv[1], "rexec") != 0) {
+ const char *noexec = argv[1];
+ argv[1] = "rexec";
+ execve(argv[0], argv, disable_execute(envp, noexec));
+ sudo_fatalx_nodebug("execve");
+ }
+
+ errors += try_execl();
+ errors += try_system();
+#ifdef HAVE_WORDEXP_H
+ errors += try_wordexp();
+#endif
+
+ return errors;
+}