From e02d5dd9b3143b2e72d2c71e914d7bd96a47bf7b Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Mon, 17 Nov 2014 13:35:58 +0100 Subject: Ensure security of default user environment --- 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 | 2 + 8 files changed, 227 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 5a0e67b158..16fa9b8a88 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 ea240975b4..e1e08662d6 100644 --- a/cpukit/libcsupport/src/pwdgrp.c +++ b/cpukit/libcsupport/src/pwdgrp.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -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 a5261a484b..a5f39d8fe1 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 80245f9c64..8efedb2385 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 0000000000..10ce651367 --- /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@.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 0000000000..8f79502174 --- /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 + * + * + * 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 +#include +#include +#include +#include +#include +#include +#include + +#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 diff --git a/testsuites/libtests/pwdgrp02/pwdgrp02.doc b/testsuites/libtests/pwdgrp02/pwdgrp02.doc new file mode 100644 index 0000000000..67e5e5c372 --- /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: + + - _libcsupport_pwdgrp_init + +concepts: + + - Ensures security of default user environment. diff --git a/testsuites/libtests/pwdgrp02/pwdgrp02.scn b/testsuites/libtests/pwdgrp02/pwdgrp02.scn new file mode 100644 index 0000000000..ca1d6aedb1 --- /dev/null +++ b/testsuites/libtests/pwdgrp02/pwdgrp02.scn @@ -0,0 +1,2 @@ +*** BEGIN OF TEST PWDGRP 2 *** +*** END OF TEST PWDGRP 2 *** -- cgit v1.2.3