[PATCH 11/22] Ensure security of default user environment
Sebastian Huber
sebastian.huber at embedded-brains.de
Tue Nov 18 14:37:17 UTC 2014
---
cpukit/libcsupport/src/base_fs.c | 5 +-
cpukit/libcsupport/src/pwdgrp.c | 17 ++-
testsuites/libtests/Makefile.am | 1 +
testsuites/libtests/configure.ac | 1 +
testsuites/libtests/pwdgrp02/Makefile.am | 19 ++++
testsuites/libtests/pwdgrp02/init.c | 180 ++++++++++++++++++++++++++++++
testsuites/libtests/pwdgrp02/pwdgrp02.doc | 11 ++
testsuites/libtests/pwdgrp02/pwdgrp02.scn | 0
8 files changed, 225 insertions(+), 9 deletions(-)
create mode 100644 testsuites/libtests/pwdgrp02/Makefile.am
create mode 100644 testsuites/libtests/pwdgrp02/init.c
create mode 100644 testsuites/libtests/pwdgrp02/pwdgrp02.doc
create mode 100644 testsuites/libtests/pwdgrp02/pwdgrp02.scn
diff --git a/cpukit/libcsupport/src/base_fs.c b/cpukit/libcsupport/src/base_fs.c
index 5a0e67b..16fa9b8 100644
--- a/cpukit/libcsupport/src/base_fs.c
+++ b/cpukit/libcsupport/src/base_fs.c
@@ -49,12 +49,9 @@ void rtems_filesystem_initialize( void )
* Traditionally RTEMS devices are under "/dev" so install this directory.
*
* If the mkdir() fails, we can't print anything so just fatal error.
- *
- * NOTE: UNIX root is 755 and owned by root/root (0/0). It is actually
- * created that way by the IMFS.
*/
- rv = mkdir( "/dev", 0777);
+ rv = mkdir( "/dev", S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH );
if ( rv != 0 )
rtems_fatal_error_occurred( 0xABCD0003 );
diff --git a/cpukit/libcsupport/src/pwdgrp.c b/cpukit/libcsupport/src/pwdgrp.c
index ea24097..e1e0866 100644
--- a/cpukit/libcsupport/src/pwdgrp.c
+++ b/cpukit/libcsupport/src/pwdgrp.c
@@ -26,6 +26,7 @@
#include <pwd.h>
#include <grp.h>
#include <errno.h>
+#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
@@ -41,11 +42,17 @@ static pthread_once_t pwdgrp_once = PTHREAD_ONCE_INIT;
static void init_file(const char *name, const char *content)
{
- FILE *fp = fopen(name, "wx");
+ /*
+ * Unlike to standard UNIX systems, these files are only readable and
+ * writeable for the root user. This way we avoid the need for an
+ * /etc/shadow. In case more UNIX compatibility is desired, this can be
+ * added on demand.
+ */
+ int fd = open(name, O_CREAT | O_EXCL | O_WRONLY, S_IRUSR | S_IWUSR);
- if (fp != NULL) {
- fputs(content, fp);
- fclose(fp);
+ if (fd >= 0) {
+ write(fd, content, strlen(content));
+ close(fd);
}
}
@@ -54,7 +61,7 @@ static void init_file(const char *name, const char *content)
*/
static void pwdgrp_init(void)
{
- mkdir("/etc", 0777);
+ mkdir("/etc", S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
/*
* Initialize /etc/passwd
diff --git a/testsuites/libtests/Makefile.am b/testsuites/libtests/Makefile.am
index 21bae23..3152742 100644
--- a/testsuites/libtests/Makefile.am
+++ b/testsuites/libtests/Makefile.am
@@ -1,6 +1,7 @@
ACLOCAL_AMFLAGS = -I ../aclocal
_SUBDIRS = POSIX
+_SUBDIRS += pwdgrp02
_SUBDIRS += shell01
_SUBDIRS += pwdgrp01
_SUBDIRS += crypt01
diff --git a/testsuites/libtests/configure.ac b/testsuites/libtests/configure.ac
index dea3d1b..400650b 100644
--- a/testsuites/libtests/configure.ac
+++ b/testsuites/libtests/configure.ac
@@ -66,6 +66,7 @@ AS_IF([test x"$HAVE_LIBDL" = x"yes"],[
# Explicitly list all Makefiles here
AC_CONFIG_FILES([Makefile
+pwdgrp02/Makefile
shell01/Makefile
pwdgrp01/Makefile
crypt01/Makefile
diff --git a/testsuites/libtests/pwdgrp02/Makefile.am b/testsuites/libtests/pwdgrp02/Makefile.am
new file mode 100644
index 0000000..10ce651
--- /dev/null
+++ b/testsuites/libtests/pwdgrp02/Makefile.am
@@ -0,0 +1,19 @@
+rtems_tests_PROGRAMS = pwdgrp02
+pwdgrp02_SOURCES = init.c
+
+dist_rtems_tests_DATA = pwdgrp02.scn pwdgrp02.doc
+
+include $(RTEMS_ROOT)/make/custom/@RTEMS_BSP at .cfg
+include $(top_srcdir)/../automake/compile.am
+include $(top_srcdir)/../automake/leaf.am
+
+AM_CPPFLAGS += -I$(top_srcdir)/../support/include
+
+LINK_OBJS = $(pwdgrp02_OBJECTS)
+LINK_LIBS = $(pwdgrp02_LDLIBS)
+
+pwdgrp02$(EXEEXT): $(pwdgrp02_OBJECTS) $(pwdgrp02_DEPENDENCIES)
+ @rm -f pwdgrp02$(EXEEXT)
+ $(make-exe)
+
+include $(top_srcdir)/../automake/local.am
diff --git a/testsuites/libtests/pwdgrp02/init.c b/testsuites/libtests/pwdgrp02/init.c
new file mode 100644
index 0000000..8f79502
--- /dev/null
+++ b/testsuites/libtests/pwdgrp02/init.c
@@ -0,0 +1,180 @@
+/*
+ * Copyright (c) 2014 embedded brains GmbH. All rights reserved.
+ *
+ * embedded brains GmbH
+ * Dornierstr. 4
+ * 82178 Puchheim
+ * Germany
+ * <rtems at embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#ifdef HAVE_CONFIG_H
+ #include "config.h"
+#endif
+
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <grp.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "tmacros.h"
+
+const char rtems_test_name[] = "PWDGRP 2";
+
+static void assert_pwd(struct passwd *pwd)
+{
+ rtems_test_assert(strcmp(pwd->pw_name, "root") == 0);
+ rtems_test_assert(strcmp(pwd->pw_passwd, "") == 0);
+ rtems_test_assert(pwd->pw_uid == 0);
+ rtems_test_assert(pwd->pw_gid == 0);
+ rtems_test_assert(strcmp(pwd->pw_comment, "") == 0);
+ rtems_test_assert(strcmp(pwd->pw_gecos, "") == 0);
+ rtems_test_assert(strcmp(pwd->pw_dir, "") == 0);
+ rtems_test_assert(strcmp(pwd->pw_shell, "") == 0);
+}
+
+static void assert_grp(struct group *grp)
+{
+ rtems_test_assert(strcmp(grp->gr_name, "root") == 0);
+ rtems_test_assert(strcmp(grp->gr_passwd, "") == 0);
+ rtems_test_assert(grp->gr_gid == 0);
+ rtems_test_assert(grp->gr_mem[0] == NULL);
+}
+
+static void assert_dir(const char *name)
+{
+ int rv;
+ struct stat st;
+
+ rv = lstat(name, &st);
+ rtems_test_assert(rv == 0);
+ rtems_test_assert(st.st_uid == 0);
+ rtems_test_assert(st.st_gid == 0);
+ rtems_test_assert(
+ st.st_mode == (S_IFDIR | S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH)
+ );
+}
+
+static void test(void)
+{
+ int rv;
+ struct passwd pwd;
+ struct group grp;
+ struct passwd *pwd_res;
+ struct group *grp_res;
+ char buf[256];
+
+ rtems_test_assert(getuid() == 0);
+ rtems_test_assert(geteuid() == 0);
+
+ rtems_test_assert(getgid() == 0);
+ rtems_test_assert(getegid() == 0);
+
+ memset(&pwd, 0xff, sizeof(pwd));
+ rv = getpwnam_r("root", &pwd, &buf[0], sizeof(buf), &pwd_res);
+ rtems_test_assert(rv == 0);
+ rtems_test_assert(&pwd == pwd_res);
+ assert_pwd(pwd_res);
+
+ memset(&pwd, 0xff, sizeof(pwd));
+ rv = getpwuid_r(0, &pwd, &buf[0], sizeof(buf), &pwd_res);
+ rtems_test_assert(rv == 0);
+ rtems_test_assert(&pwd == pwd_res);
+ assert_pwd(pwd_res);
+
+ memset(&grp, 0xff, sizeof(grp));
+ rv = getgrnam_r("root", &grp, &buf[0], sizeof(buf), &grp_res);
+ rtems_test_assert(rv == 0);
+ rtems_test_assert(&grp == grp_res);
+ assert_grp(grp_res);
+
+ memset(&grp, 0xff, sizeof(grp));
+ rv = getgrgid_r(0, &grp, &buf[0], sizeof(buf), &grp_res);
+ rtems_test_assert(rv == 0);
+ rtems_test_assert(&grp == grp_res);
+ assert_grp(grp_res);
+
+ assert_dir("/dev");
+ assert_dir("/etc");
+
+ rv = setuid(1);
+ rtems_test_assert(rv == 0);
+
+ rv = seteuid(1);
+ rtems_test_assert(rv == 0);
+
+ errno = 0;
+ rv = unlink("/etc/passwd");
+ rtems_test_assert(rv == -1);
+ rtems_test_assert(errno == EACCES);
+
+ errno = 0;
+ rv = unlink("/etc/group");
+ rtems_test_assert(rv == -1);
+ rtems_test_assert(errno == EACCES);
+
+ errno = 0;
+ rv = open("/etc/passwd", O_RDONLY);
+ rtems_test_assert(rv == -1);
+ rtems_test_assert(errno == EACCES);
+
+ errno = 0;
+ rv = open("/etc/group", O_RDONLY);
+ rtems_test_assert(rv == -1);
+ rtems_test_assert(errno == EACCES);
+
+ errno = 0;
+ rv = open("/etc/passwd", O_WRONLY);
+ rtems_test_assert(rv == -1);
+ rtems_test_assert(errno == EACCES);
+
+ errno = 0;
+ rv = open("/etc/group", O_WRONLY);
+ rtems_test_assert(rv == -1);
+ rtems_test_assert(errno == EACCES);
+
+ errno = 0;
+ rv = open("/etc/passwd", 0);
+ rtems_test_assert(rv == -1);
+ rtems_test_assert(errno == EACCES);
+
+ errno = 0;
+ rv = open("/etc/group", 0);
+ rtems_test_assert(rv == -1);
+ rtems_test_assert(errno == EACCES);
+}
+
+static void Init(rtems_task_argument arg)
+{
+ TEST_BEGIN();
+
+ test();
+
+ TEST_END();
+ rtems_test_exit(0);
+}
+
+#define CONFIGURE_APPLICATION_DOES_NOT_NEED_CLOCK_DRIVER
+#define CONFIGURE_APPLICATION_NEEDS_CONSOLE_DRIVER
+
+#define CONFIGURE_USE_IMFS_AS_BASE_FILESYSTEM
+
+#define CONFIGURE_LIBIO_MAXIMUM_FILE_DESCRIPTORS 4
+
+#define CONFIGURE_MAXIMUM_TASKS 1
+
+#define CONFIGURE_INITIAL_EXTENSIONS RTEMS_TEST_INITIAL_EXTENSION
+
+#define CONFIGURE_RTEMS_INIT_TASKS_TABLE
+
+#define CONFIGURE_INIT
+
+#include <rtems/confdefs.h>
diff --git a/testsuites/libtests/pwdgrp02/pwdgrp02.doc b/testsuites/libtests/pwdgrp02/pwdgrp02.doc
new file mode 100644
index 0000000..ea718be
--- /dev/null
+++ b/testsuites/libtests/pwdgrp02/pwdgrp02.doc
@@ -0,0 +1,11 @@
+This file describes the directives and concepts tested by this test set.
+
+test set name: pwdgrp02
+
+directives:
+
+ TBD
+
+concepts:
+
+ TBD
diff --git a/testsuites/libtests/pwdgrp02/pwdgrp02.scn b/testsuites/libtests/pwdgrp02/pwdgrp02.scn
new file mode 100644
index 0000000..e69de29
--
1.8.4.5
More information about the devel
mailing list