[PATCH v16 19/20] ipe: kunit test for parser

Fan Wu
2024-03-28T20:17:36Z

From: Deven Bowers <deven.desai@linux.microsoft.com>

Add various happy/unhappy unit tests for both IPE's policy parser.

Besides, a test suite for IPE functionality is available at
https://github.com/microsoft/ipe/tree/test-suite

Signed-off-by: Deven Bowers <deven.desai@linux.microsoft.com>
Signed-off-by: Fan Wu <wufan@linux.microsoft.com>

---
v1-v6:
+ Not present

v7:
Introduced

v8:
+ Remove the kunit tests with respect to the fsverity digest, as these
require significant changes to work with the new method of acquiring
the digest at runtime.

v9:
+ Remove the kunit tests related to ipe_context

v10:
+ No changes

v11:
+ No changes

v12:
+ No changes

v13:
+ No changes

v14:
+ No changes

v15:
+ No changes

v16:
+ No changes
---
security/ipe/Kconfig | 17 +++
security/ipe/Makefile | 3 +
security/ipe/policy_tests.c | 294 ++++++++++++++++++++++++++++++++++++
3 files changed, 314 insertions(+)
create mode 100644 security/ipe/policy_tests.c

diff --git a/security/ipe/Kconfig b/security/ipe/Kconfig
index 5c7c773ed84f..82aa8255662b 100644
--- a/security/ipe/Kconfig
+++ b/security/ipe/Kconfig
@@ -56,4 +56,21 @@ config IPE_PROP_FS_VERITY

endmenu

+config SECURITY_IPE_KUNIT_TEST
+ bool "Build KUnit tests for IPE" if !KUNIT_ALL_TESTS
+ depends on KUNIT=y
+ default KUNIT_ALL_TESTS
+ help
+ This builds the IPE KUnit tests.
+
+ KUnit tests run during boot and output the results to the debug log
+ in TAP format (https://testanything.org/). Only useful for kernel devs
+ running KUnit test harness and are not for inclusion into a
+ production build.
+
+ For more information on KUnit and unit tests in general please refer
+ to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+ If unsure, say N.
+
endif
diff --git a/security/ipe/Makefile b/security/ipe/Makefile
index ce23101b66ba..def674e09e84 100644
--- a/security/ipe/Makefile
+++ b/security/ipe/Makefile
@@ -26,3 +26,6 @@ obj-$(CONFIG_SECURITY_IPE) += \
audit.o \

clean-files := boot-policy.c \
+
+obj-$(CONFIG_SECURITY_IPE_KUNIT_TEST) += \
+ policy_tests.o \
diff --git a/security/ipe/policy_tests.c b/security/ipe/policy_tests.c
new file mode 100644
index 000000000000..d67c42c9ca59
--- /dev/null
+++ b/security/ipe/policy_tests.c
@@ -0,0 +1,294 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) Microsoft Corporation. All rights reserved.
+ */
+
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <kunit/test.h>
+#include "policy.h"
+struct policy_case {
+ const char *const policy;
+ int errno;
+ const char *const desc;
+};
+
+static const struct policy_case policy_cases[] = {
+ {
+ "policy_name=allowall policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW",
+ 0,
+ "basic",
+ },
+ {
+ "policy_name=trailing_comment policy_version=152.0.0 #This is comment\n"
+ "DEFAULT action=ALLOW",
+ 0,
+ "trailing comment",
+ },
+ {
+ "policy_name=allowallnewline policy_version=0.2.0\n"
+ "DEFAULT action=ALLOW\n"
+ "\n",
+ 0,
+ "trailing newline",
+ },
+ {
+ "policy_name=carriagereturnlinefeed policy_version=0.0.1\n"
+ "DEFAULT action=ALLOW\n"
+ "\r\n",
+ 0,
+ "clrf newline",
+ },
+ {
+ "policy_name=whitespace policy_version=0.0.0\n"
+ "DEFAULT\taction=ALLOW\n"
+ " \t DEFAULT \t op=EXECUTE action=DENY\n"
+ "op=EXECUTE boot_verified=TRUE action=ALLOW\n"
+ "# this is a\tcomment\t\t\t\t\n"
+ "DEFAULT \t op=KMODULE\t\t\t action=DENY\r\n"
+ "op=KMODULE boot_verified=TRUE action=ALLOW\n",
+ 0,
+ "various whitespaces and nested default",
+ },
+ {
+ "policy_name=boot_verified policy_version=-1236.0.0\n"
+ "DEFAULT\taction=ALLOW\n",
+ -EINVAL,
+ "negative version",
+ },
+ {
+ "policy_name=$@!*&^%%\\:;{}() policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW",
+ 0,
+ "special characters",
+ },
+ {
+ "policy_name=test policy_version=999999.0.0\n"
+ "DEFAULT action=ALLOW",
+ -ERANGE,
+ "overflow version",
+ },
+ {
+ "policy_name=test policy_version=255.0\n"
+ "DEFAULT action=ALLOW",
+ -EBADMSG,
+ "incomplete version",
+ },
+ {
+ "policy_name=test policy_version=111.0.0.0\n"
+ "DEFAULT action=ALLOW",
+ -EBADMSG,
+ "extra version",
+ },
+ {
+ "",
+ -EBADMSG,
+ "0-length policy",
+ },
+ {
+ "policy_name=test\0policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW",
+ -EBADMSG,
+ "random null in header",
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "\0DEFAULT action=ALLOW",
+ -EBADMSG,
+ "incomplete policy from NULL",
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=DENY\n\0"
+ "op=EXECUTE dmverity_signature=TRUE action=ALLOW\n",
+ 0,
+ "NULL truncates policy",
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "op=EXECUTE dmverity_signature=abc action=ALLOW",
+ -EBADMSG,
+ "invalid property type",
+ },
+ {
+ "DEFAULT action=ALLOW",
+ -EBADMSG,
+ "missing policy header",
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n",
+ -EBADMSG,
+ "missing default definition",
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "dmverity_signature=TRUE op=EXECUTE action=ALLOW",
+ -EBADMSG,
+ "invalid rule ordering"
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "action=ALLOW op=EXECUTE dmverity_signature=TRUE",
+ -EBADMSG,
+ "invalid rule ordering (2)",
+ },
+ {
+ "policy_name=test policy_version=0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "op=EXECUTE dmverity_signature=TRUE action=ALLOW",
+ -EBADMSG,
+ "invalid version",
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "op=UNKNOWN dmverity_signature=TRUE action=ALLOW",
+ -EBADMSG,
+ "unknown operation",
+ },
+ {
+ "policy_name=asdvpolicy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n",
+ -EBADMSG,
+ "missing space after policy name",
+ },
+ {
+ "policy_name=test\xFF\xEF policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "op=EXECUTE dmverity_signature=TRUE action=ALLOW",
+ 0,
+ "expanded ascii",
+ },
+ {
+ "policy_name=test\xFF\xEF policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "op=EXECUTE dmverity_roothash=GOOD_DOG action=ALLOW",
+ -EBADMSG,
+ "invalid property value (2)",
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "policy_name=test policy_version=0.1.0\n"
+ "DEFAULT action=ALLOW",
+ -EBADMSG,
+ "double header"
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "DEFAULT action=ALLOW\n",
+ -EBADMSG,
+ "double default"
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "DEFAULT op=EXECUTE action=DENY\n"
+ "DEFAULT op=EXECUTE action=ALLOW\n",
+ -EBADMSG,
+ "double operation default"
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "DEFAULT op=EXECUTE action=DEN\n",
+ -EBADMSG,
+ "invalid action value"
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "DEFAULT op=EXECUTE action\n",
+ -EBADMSG,
+ "invalid action value (2)"
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "UNKNOWN value=true\n",
+ -EBADMSG,
+ "unrecognized statement"
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "op=EXECUTE dmverity_roothash=1c0d7ee1f8343b7fbe418378e8eb22c061d7dec7 action=DENY\n",
+ -EBADMSG,
+ "old-style digest"
+ },
+ {
+ "policy_name=test policy_version=0.0.0\n"
+ "DEFAULT action=ALLOW\n"
+ "op=EXECUTE fsverity_digest=1c0d7ee1f8343b7fbe418378e8eb22c061d7dec7 action=DENY\n",
+ -EBADMSG,
+ "old-style digest"
+ }
+};
+
+static void pol_to_desc(const struct policy_case *c, char *desc)
+{
+ strscpy(desc, c->desc, KUNIT_PARAM_DESC_SIZE);
+}
+
+KUNIT_ARRAY_PARAM(ipe_policies, policy_cases, pol_to_desc);
+
+/**
+ * ipe_parser_unsigned_test - Test the parser by passing unsigned policies.
+ * @test: Supplies a pointer to a kunit structure.
+ *
+ * This is called by the kunit harness. This test does not check the correctness
+ * of the policy, but ensures that errors are handled correctly.
+ */
+static void ipe_parser_unsigned_test(struct kunit *test)
+{
+ const struct policy_case *p = test->param_value;
+ struct ipe_policy *pol = ipe_new_policy(p->policy, strlen(p->policy), NULL, 0);
+
+ if (p->errno) {
+ KUNIT_EXPECT_EQ(test, PTR_ERR(pol), p->errno);
+ return;
+ }
+
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pol);
+ KUNIT_EXPECT_NOT_ERR_OR_NULL(test, pol->parsed);
+ KUNIT_EXPECT_STREQ(test, pol->text, p->policy);
+ KUNIT_EXPECT_PTR_EQ(test, NULL, pol->pkcs7);
+ KUNIT_EXPECT_EQ(test, 0, pol->pkcs7len);
+
+ ipe_free_policy(pol);
+}
+
+/**
+ * ipe_parser_widestring_test - Ensure parser fail on a wide string policy.
+ * @test: Supplies a pointer to a kunit structure.
+ *
+ * This is called by the kunit harness.
+ */
+static void ipe_parser_widestring_test(struct kunit *test)
+{
+ struct ipe_policy *pol = NULL;
+ const unsigned short policy[] = L"policy_name=Test policy_version=0.0.0\n"
+ L"DEFAULT action=ALLOW";
+
+ pol = ipe_new_policy((const char *)policy, (ARRAY_SIZE(policy) - 1) * 2, NULL, 0);
+ KUNIT_EXPECT_TRUE(test, IS_ERR_OR_NULL(pol));
+
+ ipe_free_policy(pol);
+}
+
+static struct kunit_case ipe_parser_test_cases[] = {
+ KUNIT_CASE_PARAM(ipe_parser_unsigned_test, ipe_policies_gen_params),
+ KUNIT_CASE(ipe_parser_widestring_test),
+};
+
+static struct kunit_suite ipe_parser_test_suite = {
+ .name = "ipe-parser",
+ .test_cases = ipe_parser_test_cases,
+};
+
+kunit_test_suite(ipe_parser_test_suite);
--
2.44.0