On Mon, Nov 14, 2022 at 2:42 PM Christian Göttsche
<cgzones@xxxxxxxxxxxxxx> wrote:
>
> Add tests for neverallow assertion checks.
> This creates a foundation for the status quo, and enables to spot
> regressions in future changes to the - quite complex - assertion logic.
> One example is the support for not-self rules.
>
Thanks for doing this. It is a great start. Eventually I will look
back at the fixes I did at the beginning of the year and add some more
tests based on that. I remember that it had something to do with how
attributes and self interacted. I haven't given up on the not-self
stuff, I just have been busy with other things.
Jim
> Signed-off-by: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
> ---
> libsepol/tests/libsepol-tests.c | 2 +
> .../policies/test-neverallow/policy.conf | 298 ++++++++++++++++++
> libsepol/tests/test-neverallow.c | 172 ++++++++++
> libsepol/tests/test-neverallow.h | 10 +
> 4 files changed, 482 insertions(+)
> create mode 100644 libsepol/tests/policies/test-neverallow/policy.conf
> create mode 100644 libsepol/tests/test-neverallow.c
> create mode 100644 libsepol/tests/test-neverallow.h
>
> diff --git a/libsepol/tests/libsepol-tests.c b/libsepol/tests/libsepol-tests.c
> index 5ae6bedc..968e3cc2 100644
> --- a/libsepol/tests/libsepol-tests.c
> +++ b/libsepol/tests/libsepol-tests.c
> @@ -24,6 +24,7 @@
> #include "test-expander.h"
> #include "test-deps.h"
> #include "test-downgrade.h"
> +#include "test-neverallow.h"
>
> #include <CUnit/Basic.h>
> #include <CUnit/Console.h>
> @@ -71,6 +72,7 @@ static bool do_tests(int interactive, int verbose)
> DECLARE_SUITE(expander);
> DECLARE_SUITE(deps);
> DECLARE_SUITE(downgrade);
> + DECLARE_SUITE(neverallow);
>
> if (verbose)
> CU_basic_set_mode(CU_BRM_VERBOSE);
> diff --git a/libsepol/tests/policies/test-neverallow/policy.conf b/libsepol/tests/policies/test-neverallow/policy.conf
> new file mode 100644
> index 00000000..67a16372
> --- /dev/null
> +++ b/libsepol/tests/policies/test-neverallow/policy.conf
> @@ -0,0 +1,298 @@
> +class process
> +class blk_file
> +class chr_file
> +class dir
> +class fifo_file
> +class file
> +class lnk_file
> +class sock_file
> +
> +sid kernel
> +sid security
> +sid unlabeled
> +sid file
> +sid port
> +sid netif
> +sid netmsg
> +sid node
> +sid devnull
> +
> +class process { dyntransition transition }
> +class file { getattr ioctl open read write }
> +
> +ifdef(`enable_mls',`
> +sensitivity s0;
> +dominance { s0 }
> +category c0; category c1; category c2; category c3;
> +category c4; category c5; category c6; category c7;
> +category c8; category c9; category c10; category c11;
> +category c12; category c13; category c14; category c15;
> +category c16; category c17; category c18; category c19;
> +category c20; category c21; category c22; category c23;
> +
> +level s0:c0.c23;
> +
> +mlsconstrain file { write } ( h1 dom h2 );
> +')
> +
> +
> +########################################
> +#
> +# Test start
> +#
> +########################################
> +
> +
> +## Test 1 (basic)
> +
> +type test1_t;
> +allow test1_t test1_t : file { read write };
> +neverallow test1_t test1_t : file read;
> +
> +
> +## Test 2 (wildcard permission)
> +
> +type test2_t;
> +allow test2_t test2_t : file { read write };
> +neverallow test2_t test2_t : file *;
> +
> +
> +## Test 3 (complement permission)
> +
> +type test3_t;
> +allow test3_t test3_t : file { read write };
> +neverallow test3_t test3_t : file ~{ write };
> +
> +
> +## Test 4 (wildcard source)
> +
> +type test4_t;
> +allow test4_t test4_t : file { read write };
> +neverallow * test4_t : file read;
> +
> +
> +## Test 5 (wildcard target)
> +
> +type test5_t;
> +allow test5_t test5_t : file { read write };
> +neverallow test5_t * : file read;
> +
> +
> +## Test 6 (complement source)
> +
> +type test6_1_t;
> +type test6_2_t;
> +allow { test6_1_t test6_2_t } { test6_1_t test6_2_t } : file { read write };
> +neverallow ~{ test6_2_t } test6_1_t : file read;
> +
> +
> +## Test 7 (complement target)
> +
> +type test7_1_t;
> +type test7_2_t;
> +allow { test7_1_t test7_2_t } { test7_1_t test7_2_t } : file { read write };
> +neverallow test7_1_t ~{ test7_2_t } : file read;
> +
> +
> +## Test 8 (source attribute)
> +
> +attribute test8_a;
> +type test8_t, test8_a;
> +allow test8_a test8_a : file read;
> +allow test8_t test8_t : file write;
> +neverallow test8_a test8_t : file { read write };
> +
> +
> +## Test 9 (target attribute)
> +
> +attribute test9_a;
> +type test9_t, test9_a;
> +allow test9_a test9_a : file read;
> +allow test9_t test9_t : file write;
> +neverallow test9_t test9_a : file { read write };
> +
> +
> +## Test 10 (self)
> +
> +attribute test10_a;
> +type test10_1_t, test10_a;
> +type test10_2_t;
> +allow { test10_1_t test10_2_t } { test10_1_t test10_2_t } : file read;
> +neverallow test10_a self : file *;
> +
> +
> +## Test 11 (wildcard)
> +
> +type test11_t;
> +allow test11_t self : process *;
> +neverallow * * : process *;
> +
> +
> +## Test 12 (complement attributes)
> +
> +attribute test12_1_a;
> +attribute test12_2_a;
> +attribute test12_3_a;
> +type test12_1_t, test12_1_a;
> +type test12_2_t, test12_2_a;
> +type test12_3_t, test12_3_a;
> +allow { test12_1_a test12_2_a test12_3_a } { test12_1_a test12_2_a test12_3_a } : file *;
> +neverallow ~{ test12_1_a test12_2_t } ~{ test12_3_a } : file getattr;
> +neverallow ~{ test12_1_a } ~{ test12_2_a test12_3_t } : file open;
> +
> +
> +## Test 13 (excludes)
> +
> +attribute test13_1_a;
> +attribute test13_2_a;
> +attribute test13_3_a;
> +type test13_1_t, test13_1_a;
> +type test13_2_t, test13_2_a;
> +type test13_3_t, test13_3_a;
> +allow { test13_1_a test13_2_a test13_3_a } { test13_1_a test13_2_a test13_3_a } : file { read write };
> +neverallow { test13_1_a test13_2_a test13_3_a -test13_2_a -test13_3_t } { test13_1_a test13_2_a test13_3_a -test13_2_t -test13_3_a } : file read;
> +
> +
> +## Test 14 (misc avrules)
> +
> +type test14_t;
> +auditallow test14_t test14_t : file read;
> +dontaudit test14_t test14_t : file write;
> +neverallow test14_t test14_t : file { read write };
> +type_transition test14_t test14_t : file test14_t;
> +type_transition test14_t test14_t : file test14_t "objname";
> +neverallow test14_t test14_t : file *; # nofail
> +
> +
> +## Test 15 (extended permissions - standard allow)
> +
> +type test15_t;
> +allow test15_t self : file ioctl;
> +neverallowxperm test15_t self : file ioctl 0x1111;
> +
> +
> +## Test 16 (extended permissions - allowxperm)
> +
> +type test16_t;
> +allow test16_t self : file ioctl;
> +allowxperm test16_t self : file ioctl 0x1111;
> +neverallowxperm test16_t self : file ioctl 0x1111;
> +
> +
> +## Test 17 (extended permissions - allowxperm mismatch)
> +
> +type test17_t;
> +allow test17_t self : file ioctl;
> +allowxperm test17_t self : file ioctl 0x1111;
> +neverallowxperm test17_t self : file ioctl 0x2222; # nofail
> +
> +
> +## Test 18 (extended permissions - allowxperm range I)
> +
> +type test18_t;
> +allow test18_t self : file ioctl;
> +allowxperm test18_t self : file ioctl { 0x1100-0x1300 };
> +neverallowxperm test18_t self : file ioctl 0x1111;
> +
> +
> +## Test 19 (extended permissions - allowxperm range II)
> +
> +type test19_t;
> +allow test19_t self : file ioctl;
> +allowxperm test19_t self : file ioctl 0x1111;
> +neverallowxperm test19_t self : file ioctl { 0x1100-0x1300 };
> +
> +
> +## Test 20 (extended permissions - misc targets I)
> +
> +attribute test20_a;
> +type test20_t, test20_a;
> +
> +allow test20_a test20_a : file ioctl;
> +allowxperm test20_a test20_a : file ioctl 0x1111;
> +neverallowxperm test20_a self : file ioctl 0x1111;
> +
> +
> +## Test 21 (extended permissions - misc targets II)
> +
> +attribute test21_1_a;
> +attribute test21_2_a;
> +type test21_t, test21_1_a, test21_2_a;
> +
> +allow test21_1_a test21_1_a : file ioctl;
> +allowxperm test21_1_a test21_2_a : file ioctl 0x1111;
> +neverallowxperm test21_1_a self : file ioctl 0x1111;
> +
> +
> +## Test 22 (extended permissions - misc targets III)
> +
> +attribute test22_a;
> +type test22_t, test22_a;
> +
> +allow test22_a test22_a : file ioctl;
> +allowxperm test22_t self : file ioctl 0x1111;
> +neverallowxperm test22_a self : file ioctl 0x1111;
> +
> +
> +## Test 23 (extended permissions - misc targets IV)
> +
> +attribute test23_a;
> +type test23_t, test23_a;
> +
> +allow test23_a test23_a : file ioctl;
> +allowxperm test23_t test23_t : file ioctl 0x1111;
> +neverallowxperm test23_a self : file ioctl 0x1111;
> +
> +
> +## Test 24 (extended permissions - misc targets V)
> +
> +attribute test24_a;
> +type test24_t, test24_a;
> +
> +allow test24_a test24_a : file ioctl;
> +allowxperm test24_t test24_a : file ioctl 0x1111;
> +neverallowxperm test24_a self : file ioctl 0x1111;
> +
> +
> +## Test 25 (extended permissions - misc targets VI)
> +
> +attribute test25_a;
> +type test25_t, test25_a;
> +
> +allow test25_a test25_a : file ioctl;
> +allowxperm test25_a self : file ioctl 0x1111;
> +neverallowxperm test25_a self : file ioctl 0x1111;
> +
> +
> +## Test 26 (extended permissions - assert twice)
> +
> +attribute test26_a;
> +type test26_1_t, test26_a;
> +type test26_2_t, test26_a;
> +allow test26_a test26_a : file ioctl;
> +allowxperm test26_a test26_a : file ioctl 0x1111;
> +neverallowxperm test26_1_t test26_a : file ioctl 0x1111;
> +
> +
> +########################################
> +#
> +# Test End
> +#
> +########################################
> +
> +
> +type sys_isid;
> +role sys_role;
> +role sys_role types sys_isid;
> +gen_user(sys_user,, sys_role, s0, s0 - s0:c0.c23)
> +sid kernel gen_context(sys_user:sys_role:sys_isid, s0)
> +sid security gen_context(sys_user:sys_role:sys_isid, s0)
> +sid unlabeled gen_context(sys_user:sys_role:sys_isid, s0)
> +sid file gen_context(sys_user:sys_role:sys_isid, s0)
> +sid port gen_context(sys_user:sys_role:sys_isid, s0)
> +sid netif gen_context(sys_user:sys_role:sys_isid, s0)
> +sid netmsg gen_context(sys_user:sys_role:sys_isid, s0)
> +sid node gen_context(sys_user:sys_role:sys_isid, s0)
> +sid devnull gen_context(sys_user:sys_role:sys_isid, s0)
> +fs_use_trans devpts gen_context(sys_user:sys_role:sys_isid, s0);
> +fs_use_trans devtmpfs gen_context(sys_user:sys_role:sys_isid, s0);
> diff --git a/libsepol/tests/test-neverallow.c b/libsepol/tests/test-neverallow.c
> new file mode 100644
> index 00000000..d973a0e3
> --- /dev/null
> +++ b/libsepol/tests/test-neverallow.c
> @@ -0,0 +1,172 @@
> +#define _GNU_SOURCE /* vasprintf(3) */
> +
> +#include "test-neverallow.h"
> +
> +#include "helpers.h"
> +#include "test-common.h"
> +
> +#include <sepol/debug.h>
> +#include <sepol/policydb/link.h>
> +#include <sepol/policydb/expand.h>
> +
> +#include <stdio.h>
> +#include <stdarg.h>
> +
> +extern int mls;
> +
> +int neverallow_test_init(void)
> +{
> + return 0;
> +}
> +
> +int neverallow_test_cleanup(void)
> +{
> + return 0;
> +}
> +
> +static struct msg_list {
> + char *msg;
> + struct msg_list *next;
> +} *messages;
> +
> +static void messages_clean(void)
> +{
> + while (messages) {
> + struct msg_list *n = messages->next;
> + free(messages->msg);
> + free(messages);
> + messages = n;
> + }
> +}
> +
> +static void messages_check(unsigned count, const char *const expected[count])
> +{
> + unsigned i;
> + const struct msg_list *m = messages;
> +
> + for (i = 0; i < count; i++, m = m->next) {
> + if (!m) {
> + CU_FAIL("less messages than expected");
> + fprintf(stderr, "\n<expected %u, got %u>\n", count, i);
> + return;
> + }
> +
> + if (strcmp(expected[i], m->msg) != 0) {
> + CU_FAIL("messages differ from expected");
> + fprintf(stderr, "\n<expected: '''%s''', got: '''%s'''>\n", expected[i], m->msg);
> + }
> + }
> +
> + if (m) {
> + CU_FAIL("more messages than expected");
> + fprintf(stderr, "\n<expected %u; next message: '''%s'''>\n", count, m->msg);
> + }
> +}
> +
> +__attribute__ ((format(printf, 3, 4)))
> +static void msg_handler(void *varg __attribute__ ((unused)),
> + sepol_handle_t * handle __attribute__ ((unused)),
> + const char *fmt, ...)
> +{
> + char *msg;
> + va_list ap;
> + int r;
> +
> + va_start(ap, fmt);
> + r = vasprintf(&msg, fmt, ap);
> + if (r < 0)
> + CU_FAIL_FATAL("oom");
> + va_end(ap);
> +
> + struct msg_list *new = malloc(sizeof(*new));
> + if (!new)
> + CU_FAIL_FATAL("oom");
> + new->msg = msg;
> + new->next = messages;
> + messages = new;
> +}
> +
> +#define ARRAY_SIZE(a) (sizeof(a) / sizeof(*a))
> +
> +static void test_neverallow_basic(void)
> +{
> + policydb_t basemod, base_expanded;
> + sepol_handle_t *handle;
> + static const char *const expected_messages[] = {
> + "30 neverallow failures occurred",
> + "neverallow on line 53 of policies/test-neverallow/policy.conf.std (or line 53 of policies/test-neverallow/policy.conf.std) violated by allow test1_t test1_t:file { read };",
> + "neverallow on line 60 of policies/test-neverallow/policy.conf.std (or line 60 of policies/test-neverallow/policy.conf.std) violated by allow test2_t test2_t:file { read write };",
> + "neverallow on line 67 of policies/test-neverallow/policy.conf.std (or line 67 of policies/test-neverallow/policy.conf.std) violated by allow test3_t test3_t:file { read };",
> + "neverallow on line 74 of policies/test-neverallow/policy.conf.std (or line 74 of policies/test-neverallow/policy.conf.std) violated by allow test4_t test4_t:file { read };",
> + "neverallow on line 81 of policies/test-neverallow/policy.conf.std (or line 81 of policies/test-neverallow/policy.conf.std) violated by allow test5_t test5_t:file { read };",
> + "neverallow on line 89 of policies/test-neverallow/policy.conf.std (or line 89 of policies/test-neverallow/policy.conf.std) violated by allow test6_1_t test6_1_t:file { read };",
> + "neverallow on line 97 of policies/test-neverallow/policy.conf.std (or line 97 of policies/test-neverallow/policy.conf.std) violated by allow test7_1_t test7_1_t:file { read };",
> + "neverallow on line 106 of policies/test-neverallow/policy.conf.std (or line 106 of policies/test-neverallow/policy.conf.std) violated by allow test8_t test8_t:file { write };",
> + "neverallow on line 106 of policies/test-neverallow/policy.conf.std (or line 106 of policies/test-neverallow/policy.conf.std) violated by allow test8_t test8_t:file { read };",
> + "neverallow on line 115 of policies/test-neverallow/policy.conf.std (or line 115 of policies/test-neverallow/policy.conf.std) violated by allow test9_t test9_t:file { read };",
> + "neverallow on line 115 of policies/test-neverallow/policy.conf.std (or line 115 of policies/test-neverallow/policy.conf.std) violated by allow test9_t test9_t:file { write };",
> + "neverallow on line 124 of policies/test-neverallow/policy.conf.std (or line 124 of policies/test-neverallow/policy.conf.std) violated by allow test10_1_t test10_1_t:file { read };",
> + "neverallow on line 131 of policies/test-neverallow/policy.conf.std (or line 131 of policies/test-neverallow/policy.conf.std) violated by allow test11_t test11_t:process { dyntransition transition };",
> + "neverallow on line 143 of policies/test-neverallow/policy.conf.std (or line 143 of policies/test-neverallow/policy.conf.std) violated by allow test12_3_t test12_1_t:file { getattr };",
> + "neverallow on line 143 of policies/test-neverallow/policy.conf.std (or line 143 of policies/test-neverallow/policy.conf.std) violated by allow test12_3_t test12_2_t:file { getattr };",
> + "neverallow on line 144 of policies/test-neverallow/policy.conf.std (or line 144 of policies/test-neverallow/policy.conf.std) violated by allow test12_3_t test12_1_t:file { open };",
> + "neverallow on line 144 of policies/test-neverallow/policy.conf.std (or line 144 of policies/test-neverallow/policy.conf.std) violated by allow test12_2_t test12_1_t:file { open };",
> + "neverallow on line 156 of policies/test-neverallow/policy.conf.std (or line 156 of policies/test-neverallow/policy.conf.std) violated by allow test13_1_t test13_1_t:file { read };",
> + "neverallowxperm on line 174 of policies/test-neverallow/policy.conf.std (or line 174 of policies/test-neverallow/policy.conf.std) violated by\nallow test15_t test15_t:file { ioctl };",
> + "neverallowxperm on line 182 of policies/test-neverallow/policy.conf.std (or line 182 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test16_t test16_t:file ioctl { 0x1111 };",
> + "neverallowxperm on line 198 of policies/test-neverallow/policy.conf.std (or line 198 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test18_t test18_t:file ioctl { 0x1111 };",
> + "neverallowxperm on line 206 of policies/test-neverallow/policy.conf.std (or line 206 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test19_t test19_t:file ioctl { 0x1111 };",
> + "neverallowxperm on line 216 of policies/test-neverallow/policy.conf.std (or line 216 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test20_a test20_a:file ioctl { 0x1111 };",
> + "neverallowxperm on line 227 of policies/test-neverallow/policy.conf.std (or line 227 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test21_1_a test21_2_a:file ioctl { 0x1111 };",
> + "neverallowxperm on line 237 of policies/test-neverallow/policy.conf.std (or line 237 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test22_t test22_t:file ioctl { 0x1111 };",
> + "neverallowxperm on line 247 of policies/test-neverallow/policy.conf.std (or line 247 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test23_t test23_t:file ioctl { 0x1111 };",
> + "neverallowxperm on line 257 of policies/test-neverallow/policy.conf.std (or line 257 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test24_t test24_a:file ioctl { 0x1111 };",
> + "neverallowxperm on line 267 of policies/test-neverallow/policy.conf.std (or line 267 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test25_t test25_t:file ioctl { 0x1111 };",
> + "neverallowxperm on line 277 of policies/test-neverallow/policy.conf.std (or line 277 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test26_a test26_a:file ioctl { 0x1111 };",
> + "neverallowxperm on line 277 of policies/test-neverallow/policy.conf.std (or line 277 of policies/test-neverallow/policy.conf.std) violated by\nallowxperm test26_a test26_a:file ioctl { 0x1111 };",
> + };
> +
> + if (policydb_init(&base_expanded))
> + CU_FAIL_FATAL("Failed to initialize policy");
> +
> + if (test_load_policy(&basemod, POLICY_BASE, mls, "test-neverallow", "policy.conf"))
> + CU_FAIL_FATAL("Failed to load policy");
> +
> + if (link_modules(NULL, &basemod, NULL, 0, 0))
> + CU_FAIL_FATAL("Failed to link base module");
> +
> + if (expand_module(NULL, &basemod, &base_expanded, 0, 0))
> + CU_FAIL_FATAL("Failed to expand policy");
> +
> + if ((handle = sepol_handle_create()) == NULL)
> + CU_FAIL_FATAL("Failed to initialize handle");
> +
> + sepol_msg_set_callback(handle, msg_handler, NULL);
> +
> + if (check_assertions(handle, &base_expanded, base_expanded.global->branch_list->avrules) != -1)
> + CU_FAIL("Assertions did not trigger");
> +
> + messages_check(ARRAY_SIZE(expected_messages), expected_messages);
> +
> + sepol_handle_destroy(handle);
> + messages_clean();
> + policydb_destroy(&basemod);
> + policydb_destroy(&base_expanded);
> +}
> +
> +int neverallow_add_tests(CU_pSuite suite)
> +{
> + /*
> + * neverallow rules operate only on types and are unaffected by MLS
> + * (avoid adjusting the messages for std and mls)
> + */
> + if (mls)
> + return 0;
> +
> + if (NULL == CU_add_test(suite, "neverallow_basic", test_neverallow_basic)) {
> + CU_cleanup_registry();
> + return CU_get_error();
> + }
> +
> + return 0;
> +}
> diff --git a/libsepol/tests/test-neverallow.h b/libsepol/tests/test-neverallow.h
> new file mode 100644
> index 00000000..d3c2a74e
> --- /dev/null
> +++ b/libsepol/tests/test-neverallow.h
> @@ -0,0 +1,10 @@
> +#ifndef TEST_NEVERALLOW_H__
> +#define TEST_NEVERALLOW_H__
> +
> +#include <CUnit/Basic.h>
> +
> +int neverallow_test_init(void);
> +int neverallow_test_cleanup(void);
> +int neverallow_add_tests(CU_pSuite suite);
> +
> +#endif /* TEST_NEVERALLOW_H__ */
> --
> 2.38.1
>
