[PATCH v6 14/15] selftests/digest_cache: Add selftests for the Integrity Digest Cache
Roberto Sassu
roberto.sassu at huaweicloud.com
Tue Nov 19 10:49:21 UTC 2024
From: Roberto Sassu <roberto.sassu at huawei.com>
Add tests to verify the correctness of the Integrity Digest Cache, in
all_test.c.
Add the kernel module digest_cache_kern.ko, to let all_test call the API
of the Integrity Digest Cache through the newly introduced
digest_cache_test file in <securityfs>/integrity/digest_cache.
Test coverage information:
File 'security/integrity/digest_cache/reset.c'
Lines executed:100.00% of 53
File 'security/integrity/digest_cache/main.c'
Lines executed:90.29% of 206
File 'security/integrity/digest_cache/modsig.c'
Lines executed:42.86% of 21
File 'security/integrity/digest_cache/htable.c'
Lines executed:93.90% of 82
File 'security/integrity/digest_cache/populate.c'
Lines executed:89.19% of 37
File 'security/integrity/digest_cache/verif.c'
Lines executed:85.11% of 47
File 'security/integrity/digest_cache/dir.c'
Lines executed:90.18% of 163
File 'security/integrity/digest_cache/parsers.c'
Lines executed:45.74% of 94
File 'security/integrity/digest_cache/secfs.c'
Lines executed:56.00% of 25
File 'security/integrity/digest_cache/parsers/tlv.c'
Lines executed:75.26% of 97
Signed-off-by: Roberto Sassu <roberto.sassu at huawei.com>
---
tools/testing/selftests/Makefile | 1 +
.../testing/selftests/digest_cache/.gitignore | 3 +
tools/testing/selftests/digest_cache/Makefile | 24 +
.../testing/selftests/digest_cache/all_test.c | 769 ++++++++++++++++++
tools/testing/selftests/digest_cache/common.c | 78 ++
tools/testing/selftests/digest_cache/common.h | 93 +++
.../selftests/digest_cache/common_user.c | 33 +
.../selftests/digest_cache/common_user.h | 15 +
tools/testing/selftests/digest_cache/config | 2 +
.../selftests/digest_cache/generators.c | 130 +++
.../selftests/digest_cache/generators.h | 16 +
.../selftests/digest_cache/testmod/Makefile | 16 +
.../selftests/digest_cache/testmod/kern.c | 551 +++++++++++++
13 files changed, 1731 insertions(+)
create mode 100644 tools/testing/selftests/digest_cache/.gitignore
create mode 100644 tools/testing/selftests/digest_cache/Makefile
create mode 100644 tools/testing/selftests/digest_cache/all_test.c
create mode 100644 tools/testing/selftests/digest_cache/common.c
create mode 100644 tools/testing/selftests/digest_cache/common.h
create mode 100644 tools/testing/selftests/digest_cache/common_user.c
create mode 100644 tools/testing/selftests/digest_cache/common_user.h
create mode 100644 tools/testing/selftests/digest_cache/config
create mode 100644 tools/testing/selftests/digest_cache/generators.c
create mode 100644 tools/testing/selftests/digest_cache/generators.h
create mode 100644 tools/testing/selftests/digest_cache/testmod/Makefile
create mode 100644 tools/testing/selftests/digest_cache/testmod/kern.c
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index b38199965f99..e6fc3c984923 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -16,6 +16,7 @@ TARGETS += cpu-hotplug
TARGETS += damon
TARGETS += devices/error_logs
TARGETS += devices/probe
+TARGETS += digest_cache
TARGETS += dmabuf-heaps
TARGETS += drivers/dma-buf
TARGETS += drivers/s390x/uvdevice
diff --git a/tools/testing/selftests/digest_cache/.gitignore b/tools/testing/selftests/digest_cache/.gitignore
new file mode 100644
index 000000000000..392096e18f4e
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/.gitignore
@@ -0,0 +1,3 @@
+/*.mod
+/*_test
+/*.ko
diff --git a/tools/testing/selftests/digest_cache/Makefile b/tools/testing/selftests/digest_cache/Makefile
new file mode 100644
index 000000000000..1b819201f406
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/Makefile
@@ -0,0 +1,24 @@
+# SPDX-License-Identifier: GPL-2.0
+TEST_GEN_PROGS_EXTENDED = digest_cache_kern.ko
+TEST_GEN_PROGS := all_test
+
+$(OUTPUT)/%.ko: $(wildcard common.[ch]) testmod/Makefile testmod/kern.c
+ $(call msg,MOD,,$@)
+ $(Q)$(MAKE) -C testmod
+ $(Q)cp testmod/digest_cache_kern.ko $@
+
+LOCAL_HDRS += common.h common_user.h generators.h
+CFLAGS += -ggdb -Wall -Wextra $(KHDR_INCLUDES)
+
+OVERRIDE_TARGETS := 1
+override define CLEAN
+ $(call msg,CLEAN)
+ $(Q)$(MAKE) -C testmod clean
+ rm -Rf $(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED)
+ rm -Rf $(OUTPUT)/common.o $(OUTPUT)/common_user.o $(OUTPUT)/generators.o
+ rm -Rf $(OUTPUT)/common.mod
+endef
+
+include ../lib.mk
+
+$(OUTPUT)/all_test: common.c common.h common_user.c common_user.h generators.c
diff --git a/tools/testing/selftests/digest_cache/all_test.c b/tools/testing/selftests/digest_cache/all_test.c
new file mode 100644
index 000000000000..a283068f3cab
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/all_test.c
@@ -0,0 +1,769 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu at huawei.com>
+ *
+ * Implement the tests of the Integrity Digest Cache.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <limits.h>
+#include <fts.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/xattr.h>
+#include <sys/syscall.h>
+#include <linux/module.h>
+
+#include "generators.h"
+
+#include "../kselftest_harness.h"
+#include "../../../../include/uapi/linux/xattr.h"
+
+#define BASE_DIR_TEMPLATE "/tmp/digest_cache_test_dirXXXXXX"
+#define DIGEST_LISTS_SUBDIR "digest_lists"
+#define NUM_DIGEST_LISTS_PREFETCH MAX_WORKS
+
+FIXTURE(shared_data) {
+ char base_dir[sizeof(BASE_DIR_TEMPLATE)];
+ char digest_lists_dir[sizeof(BASE_DIR_TEMPLATE) +
+ sizeof(DIGEST_LISTS_SUBDIR)];
+ int base_dirfd, digest_lists_dirfd, kernfd, pathfd, cmd_len, no_kprobe;
+};
+
+FIXTURE_SETUP(shared_data)
+{
+ char cmd[1024];
+ int ret, fd, i, cmd_len;
+
+ /* Create the base directory. */
+ snprintf(self->base_dir, sizeof(self->base_dir), BASE_DIR_TEMPLATE);
+ ASSERT_NE(NULL, mkdtemp(self->base_dir));
+
+ /* Open base directory. */
+ self->base_dirfd = open(self->base_dir, O_RDONLY | O_DIRECTORY);
+ ASSERT_NE(-1, self->base_dirfd);
+
+ /* Create the digest_lists subdirectory. */
+ snprintf(self->digest_lists_dir, sizeof(self->digest_lists_dir),
+ "%s/%s", self->base_dir, DIGEST_LISTS_SUBDIR);
+ ASSERT_EQ(0, mkdirat(self->base_dirfd, DIGEST_LISTS_SUBDIR, 0600));
+ self->digest_lists_dirfd = openat(self->base_dirfd, DIGEST_LISTS_SUBDIR,
+ O_RDONLY | O_DIRECTORY);
+ ASSERT_NE(-1, self->digest_lists_dirfd);
+
+ fd = open("digest_cache_kern.ko", O_RDONLY);
+ ASSERT_LT(0, fd);
+
+ ASSERT_EQ(0, syscall(SYS_finit_module, fd, "", 0));
+ close(fd);
+
+ /* Open kernel test interface. */
+ self->kernfd = open(DIGEST_CACHE_TEST_INTERFACE, O_RDWR, 0600);
+ ASSERT_NE(-1, self->kernfd);
+
+ /* Open kernel digest list path interface. */
+ self->pathfd = open(DIGEST_CACHE_PATH_INTERFACE, O_RDWR, 0600);
+ ASSERT_NE(-1, self->pathfd);
+
+ /* Write the path of the digest lists directory. */
+ ASSERT_LT(0, write(self->pathfd, self->digest_lists_dir,
+ strlen(self->digest_lists_dir)));
+
+ /* Ensure that no verifier is enabled at the beginning of a test. */
+ for (i = 0; i < VERIF__LAST; i++) {
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s",
+ commands_str[DIGEST_CACHE_DISABLE_VERIF],
+ verifs_str[i]);
+ ret = write(self->kernfd, cmd, cmd_len);
+ if (ret < 0 && errno == EOPNOTSUPP) {
+ self->no_kprobe = 1;
+ break;
+ }
+
+ ASSERT_EQ(cmd_len, ret);
+ }
+}
+
+FIXTURE_TEARDOWN(shared_data)
+{
+ FTS *fts = NULL;
+ FTSENT *ftsent;
+ int fts_flags = (FTS_PHYSICAL | FTS_COMFOLLOW | FTS_NOCHDIR | FTS_XDEV);
+ char *paths[2] = { self->base_dir, NULL };
+ char cmd[1024];
+ int cmd_len;
+
+ /* Close digest_lists subdirectory. */
+ close(self->digest_lists_dirfd);
+
+ /* Close base directory. */
+ close(self->base_dirfd);
+
+ /* Delete files and directories. */
+ fts = fts_open(paths, fts_flags, NULL);
+ if (fts) {
+ while ((ftsent = fts_read(fts)) != NULL) {
+ switch (ftsent->fts_info) {
+ case FTS_DP:
+ rmdir(ftsent->fts_accpath);
+ break;
+ case FTS_F:
+ case FTS_SL:
+ case FTS_SLNONE:
+ case FTS_DEFAULT:
+ unlink(ftsent->fts_accpath);
+ break;
+ default:
+ break;
+ }
+ }
+ }
+
+ /* Release digest cache reference, if the test was interrupted. */
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s",
+ commands_str[DIGEST_CACHE_PUT]);
+ write(self->kernfd, cmd, cmd_len);
+
+ /* Close kernel test interface. */
+ close(self->kernfd);
+
+ /* Close kernel digest list path interface. */
+ close(self->pathfd);
+
+ syscall(SYS_delete_module, "digest_cache_kern", 0);
+}
+
+static int _query_test(int kernfd, char *base_dir, char *filename,
+ enum hash_algo algo, int start_number, int num_digests,
+ bool write_digest_list, int digest_lists_dirfd,
+ char *digest_list_filename)
+{
+ u8 digest[MAX_DIGEST_SIZE] = { 0 };
+ char digest_str[MAX_DIGEST_SIZE * 2 + 1] = { 0 };
+ int digest_len = hash_digest_size[algo];
+ char cmd[1024];
+ int ret, fd, i, cmd_len;
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s/%s",
+ commands_str[DIGEST_CACHE_GET], base_dir, filename);
+ ret = write(kernfd, cmd, cmd_len);
+ if (ret != cmd_len)
+ return -errno;
+
+ if (write_digest_list) {
+ fd = openat(digest_lists_dirfd, digest_list_filename, O_WRONLY);
+ if (fd < 0)
+ return -errno;
+
+ close(fd);
+ }
+
+ ret = 0;
+
+ *(u32 *)digest = start_number;
+
+ for (i = 0; i < num_digests; i++) {
+ bin2hex(digest_str, digest, digest_len);
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s/%s|%s:%s",
+ commands_str[DIGEST_CACHE_LOOKUP], base_dir,
+ filename, hash_algo_name[algo], digest_str);
+ ret = write(kernfd, cmd, cmd_len);
+ if (ret != cmd_len) {
+ ret = -errno;
+ goto out;
+ } else {
+ ret = 0;
+ }
+
+ (*(u32 *)digest)++;
+ }
+out:
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s",
+ commands_str[DIGEST_CACHE_PUT]);
+ write(kernfd, cmd, cmd_len);
+ return ret;
+}
+
+static int query_test(int kernfd, char *base_dir, char *filename,
+ enum hash_algo algo, int start_number, int num_digests)
+{
+ return _query_test(kernfd, base_dir, filename, algo, start_number,
+ num_digests, false, -1, NULL);
+}
+
+static int query_test_write(int kernfd, char *base_dir, char *filename,
+ enum hash_algo algo, int start_number,
+ int num_digests, int digest_lists_dirfd,
+ char *digest_list_filename)
+{
+ return _query_test(kernfd, base_dir, filename, algo, start_number,
+ num_digests, true, digest_lists_dirfd,
+ digest_list_filename);
+}
+
+static void test_parser(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata,
+ char *digest_list_filename, char *filename,
+ enum hash_algo algo, int start_number, int num_digests,
+ unsigned int failure)
+{
+ int expected_ret = (failure) ? -ENOENT : 0;
+
+ if (!strncmp(digest_list_filename, "tlv-", 4)) {
+ ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd,
+ digest_list_filename, algo,
+ start_number, num_digests,
+ (enum tlv_failures)failure));
+ }
+
+ ASSERT_EQ(0, create_file(self->base_dirfd, filename,
+ digest_list_filename));
+ ASSERT_EQ(expected_ret, query_test(self->kernfd, self->base_dir,
+ filename, algo, start_number,
+ num_digests));
+
+ unlinkat(self->digest_lists_dirfd, digest_list_filename, 0);
+ unlinkat(self->base_dirfd, filename, 0);
+}
+
+/*
+ * Verify that the tlv digest list parser returns success on well-formatted
+ * digest lists, for each defined hash algorithm.
+ */
+TEST_F(shared_data, tlv_parser_ok)
+{
+ enum hash_algo algo;
+
+ /* Test every known algorithm. */
+ for (algo = 0; algo < HASH_ALGO__LAST; algo++)
+ test_parser(self, _metadata, "tlv-digest_list", "file", algo,
+ 0, 5, TLV_NO_FAILURE);
+}
+
+/*
+ * Verify that the tlv digest list parser returns failure on invalid digest
+ * lists.
+ */
+TEST_F(shared_data, tlv_parser_error)
+{
+ enum tlv_failures failure;
+
+ /* Test every failure. */
+ for (failure = 0; failure < TLV_FAILURE__LAST; failure++)
+ test_parser(self, _metadata, "tlv-digest_list", "file",
+ HASH_ALGO_SHA224, 0, 1, failure);
+}
+
+static void test_default_path(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata, bool file)
+{
+ char path[PATH_MAX];
+ size_t path_len;
+
+ if (file) {
+ path_len = snprintf(path, sizeof(path),
+ "%s/%s/tlv-digest_list", self->base_dir,
+ DIGEST_LISTS_SUBDIR);
+ ASSERT_LT(0, write(self->pathfd, path, path_len));
+ }
+
+ ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd, "tlv-digest_list",
+ HASH_ALGO_SHA1, 0, 1, TLV_NO_FAILURE));
+
+ ASSERT_EQ(0, create_file(self->base_dirfd, "file", NULL));
+
+ ASSERT_EQ(0, query_test(self->kernfd, self->base_dir, "file",
+ HASH_ALGO_SHA1, 0, 1));
+}
+
+/*
+ * Verify that the digest cache created from the default path (regular file)
+ * can be retrieved and used for lookup.
+ */
+TEST_F(shared_data, default_path_file)
+{
+ test_default_path(self, _metadata, true);
+}
+
+/*
+ * Verify that the digest cache created from the default path (directory)
+ * can be retrieved and used for lookup.
+ */
+TEST_F(shared_data, default_path_dir)
+{
+ test_default_path(self, _metadata, false);
+}
+
+static void test_file_changes(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata,
+ enum file_changes change)
+{
+ char digest_list_filename[] = "tlv-digest_list";
+ char digest_list_filename_new[] = "tlv-digest_list6";
+ char digest_list_filename_xattr[] = "tlv-digest_list7";
+ char digest_list_path[sizeof(self->digest_lists_dir) +
+ sizeof(digest_list_filename)];
+ int fd;
+
+ ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd,
+ digest_list_filename, HASH_ALGO_SHA1, 0, 1,
+ TLV_NO_FAILURE));
+
+ ASSERT_EQ(0, create_file(self->base_dirfd, "file",
+ digest_list_filename));
+
+ ASSERT_EQ(0, query_test(self->kernfd, self->base_dir, "file",
+ HASH_ALGO_SHA1, 0, 1));
+
+ switch (change) {
+ case FILE_WRITE:
+ fd = openat(self->digest_lists_dirfd, digest_list_filename,
+ O_WRONLY);
+ ASSERT_NE(-1, fd);
+
+ ASSERT_EQ(4, write(fd, "1234", 4));
+ close(fd);
+ break;
+ case FILE_TRUNCATE:
+ snprintf(digest_list_path, sizeof(digest_list_path),
+ "%s/%s", self->digest_lists_dir, digest_list_filename);
+ ASSERT_EQ(0, truncate(digest_list_path, 4));
+ break;
+ case FILE_FTRUNCATE:
+ fd = openat(self->digest_lists_dirfd, digest_list_filename,
+ O_WRONLY);
+ ASSERT_NE(-1, fd);
+ ASSERT_EQ(0, ftruncate(fd, 4));
+ close(fd);
+ break;
+ case FILE_UNLINK:
+ ASSERT_EQ(0, unlinkat(self->digest_lists_dirfd,
+ digest_list_filename, 0));
+ break;
+ case FILE_RENAME:
+ ASSERT_EQ(0, renameat(self->digest_lists_dirfd,
+ digest_list_filename,
+ self->digest_lists_dirfd,
+ digest_list_filename_new));
+ break;
+ case FILE_SETXATTR:
+ fd = openat(self->base_dirfd, "file", O_WRONLY);
+ ASSERT_NE(-1, fd);
+
+ ASSERT_EQ(0, fsetxattr(fd, XATTR_NAME_DIGEST_LIST,
+ digest_list_filename_xattr,
+ strlen(digest_list_filename_xattr) + 1,
+ 0));
+ close(fd);
+ break;
+ case FILE_REMOVEXATTR:
+ fd = openat(self->base_dirfd, "file", O_WRONLY);
+ ASSERT_NE(-1, fd);
+
+ ASSERT_EQ(0, fremovexattr(fd, XATTR_NAME_DIGEST_LIST));
+ close(fd);
+
+ /*
+ * Removing security.digest_list does not cause a failure,
+ * the digest can be still retrieved via directory lookup.
+ */
+ ASSERT_EQ(0, query_test(self->kernfd, self->base_dir, "file",
+ HASH_ALGO_SHA1, 0, 1));
+
+ return;
+ default:
+ break;
+ }
+
+ ASSERT_NE(0, query_test(self->kernfd, self->base_dir, "file",
+ HASH_ALGO_SHA1, 0, 1));
+}
+
+/*
+ * Verify that operations on a digest list cause a reset of the digest cache,
+ * and that the digest is not found in the invalid/missing digest list.
+ */
+TEST_F(shared_data, file_reset)
+{
+ enum file_changes change;
+
+ /* Test for every file change. */
+ for (change = 0; change < FILE_CHANGE__LAST; change++)
+ test_file_changes(self, _metadata, change);
+}
+
+/*
+ * Verify that digest lookup does not work after a reset, and attempt the
+ * query a second time, which should instead succeed.
+ */
+TEST_F(shared_data, file_reset_again)
+{
+ char digest_list_filename[] = "tlv-digest_list";
+
+ ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd,
+ digest_list_filename, HASH_ALGO_SHA1, 0, 1,
+ TLV_NO_FAILURE));
+
+ ASSERT_EQ(0, create_file(self->base_dirfd, "file",
+ digest_list_filename));
+
+ ASSERT_NE(0, query_test_write(self->kernfd, self->base_dir, "file",
+ HASH_ALGO_SHA1, 0, 1,
+ self->digest_lists_dirfd,
+ digest_list_filename));
+
+ ASSERT_EQ(0, query_test(self->kernfd, self->base_dir, "file",
+ HASH_ALGO_SHA1, 0, 1));
+}
+
+static void query_test_with_failures(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata,
+ int start_number, int num_digests,
+ int *removed, int num_removed)
+{
+ char filename[NAME_MAX + 1];
+ int i, j, expected_ret;
+
+ for (i = start_number; i < start_number + num_digests; i++) {
+ expected_ret = 0;
+
+ for (j = 0; j < num_removed; j++) {
+ if (removed[j] == i) {
+ expected_ret = -ENOENT;
+ break;
+ }
+ }
+
+ snprintf(filename, sizeof(filename), "file%d", i);
+
+ ASSERT_EQ(expected_ret, query_test(self->kernfd, self->base_dir,
+ filename, HASH_ALGO_SHA1, i,
+ 1));
+ }
+}
+
+/*
+ * Verify that changes in the digest list directory are monitored and that
+ * a digest cannot be found if the respective digest list file has been moved
+ * away from the directory, and that a digest can be found if the respective
+ * digest list has been moved/created in the directory.
+ */
+TEST_F(shared_data, dir_reset)
+{
+ char filename[NAME_MAX + 1];
+ int i, removed[10];
+
+ for (i = 0; i < 10; i++) {
+ snprintf(filename, sizeof(filename), "file%d", i);
+ ASSERT_EQ(0, create_file(self->base_dirfd, filename, NULL));
+ snprintf(filename, sizeof(filename), "tlv-digest_list%d", i);
+ ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd,
+ filename, HASH_ALGO_SHA1, i, 1,
+ TLV_NO_FAILURE));
+ }
+
+ query_test_with_failures(self, _metadata, 0, 10, removed, 0);
+
+ ASSERT_EQ(0, unlinkat(self->digest_lists_dirfd, "tlv-digest_list7", 0));
+
+ removed[0] = 7;
+
+ query_test_with_failures(self, _metadata, 0, 10, removed, 1);
+
+ ASSERT_EQ(0, renameat(self->digest_lists_dirfd, "tlv-digest_list6",
+ self->base_dirfd, "tlv-digest_list6"));
+
+ removed[1] = 6;
+
+ query_test_with_failures(self, _metadata, 0, 10, removed, 2);
+
+ ASSERT_EQ(0, renameat(self->base_dirfd, "tlv-digest_list6",
+ self->digest_lists_dirfd, "tlv-digest_list6"));
+
+ query_test_with_failures(self, _metadata, 0, 10, removed, 1);
+
+ ASSERT_EQ(0, create_file(self->base_dirfd, "file10", NULL));
+ ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd, "tlv-digest_list10",
+ HASH_ALGO_SHA1, 10, 1, TLV_NO_FAILURE));
+
+ query_test_with_failures(self, _metadata, 0, 11, removed, 1);
+}
+
+static void _check_verif_data(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata,
+ char *digest_list_filename, int num,
+ enum hash_algo algo, bool check_dir)
+{
+ char digest_list_filename_kernel[NAME_MAX + 1];
+ char cmd[1024], number[20];
+ u8 digest[MAX_DIGEST_SIZE] = { 0 };
+ char digest_str[MAX_DIGEST_SIZE * 2 + 1] = { 0 };
+ int len, cmd_len;
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s/file",
+ commands_str[DIGEST_CACHE_GET], self->base_dir);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ /*
+ * If a directory digest cache was requested, we need to do a lookup,
+ * to make the kernel module retrieve verification data from the digest
+ * cache of the directory entry.
+ */
+ if (check_dir) {
+ *(u32 *)digest = num;
+
+ bin2hex(digest_str, digest, hash_digest_size[algo]);
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s/file|%s:%s",
+ commands_str[DIGEST_CACHE_LOOKUP],
+ self->base_dir, hash_algo_name[algo],
+ digest_str);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+ }
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s",
+ commands_str[DIGEST_CACHE_SET_VERIF],
+ verifs_str[VERIF_FILENAMES]);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ ASSERT_LT(0, read(self->kernfd, digest_list_filename_kernel,
+ sizeof(digest_list_filename_kernel)));
+ ASSERT_EQ(0, strcmp(digest_list_filename, digest_list_filename_kernel));
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s",
+ commands_str[DIGEST_CACHE_SET_VERIF],
+ verifs_str[VERIF_NUMBER]);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ len = read(self->kernfd, number, sizeof(number) - 1);
+ ASSERT_LT(0, len);
+ number[len] = '\0';
+ ASSERT_EQ(num, atoi(number));
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s",
+ commands_str[DIGEST_CACHE_PUT]);
+ write(self->kernfd, cmd, cmd_len);
+}
+
+static void check_verif_data(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata)
+{
+ char digest_list_filename[NAME_MAX + 1];
+ char cmd[1024];
+ int i, cmd_len;
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s",
+ commands_str[DIGEST_CACHE_ENABLE_VERIF],
+ verifs_str[VERIF_FILENAMES]);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s",
+ commands_str[DIGEST_CACHE_ENABLE_VERIF],
+ verifs_str[VERIF_NUMBER]);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ /*
+ * Reverse order is intentional, so that directory entries are created
+ * in the opposite order as when they are searched (when prefetching is
+ * requested).
+ */
+ for (i = 10; i >= 0; i--) {
+ snprintf(digest_list_filename, sizeof(digest_list_filename),
+ "%d-tlv-digest_list%d", i, i);
+ ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd,
+ digest_list_filename, HASH_ALGO_SHA1,
+ i, 1, TLV_NO_FAILURE));
+
+ ASSERT_EQ(0, create_file(self->base_dirfd, "file",
+ digest_list_filename));
+
+ _check_verif_data(self, _metadata, digest_list_filename, i,
+ HASH_ALGO_SHA1, false);
+
+ ASSERT_EQ(0, unlinkat(self->base_dirfd, "file", 0));
+ }
+
+ for (i = 0; i < 11; i++) {
+ ASSERT_EQ(0, create_file(self->base_dirfd, "file", NULL));
+ snprintf(digest_list_filename, sizeof(digest_list_filename),
+ "%d-tlv-digest_list%d", i, i);
+ _check_verif_data(self, _metadata, digest_list_filename, i,
+ HASH_ALGO_SHA1, true);
+ ASSERT_EQ(0, unlinkat(self->base_dirfd, "file", 0));
+ }
+}
+
+/*
+ * Verify that the correct verification data can be retrieved from the digest
+ * caches (without digest list prefetching).
+ */
+TEST_F(shared_data, verif_data_no_prefetch)
+{
+ if (self->no_kprobe)
+ SKIP(return, "CONFIG_DYNAMIC_FTRACE_WITH_ARGS not enabled");
+
+ check_verif_data(self, _metadata);
+}
+
+/*
+ * Verify that the correct verification data can be retrieved from the digest
+ * caches (with digest list prefetching).
+ */
+TEST_F(shared_data, verif_data_prefetch)
+{
+ if (self->no_kprobe)
+ SKIP(return, "CONFIG_DYNAMIC_FTRACE_WITH_ARGS not enabled");
+
+ ASSERT_EQ(0, lsetxattr(self->base_dir, XATTR_NAME_DIG_PREFETCH,
+ "1", 1, 0));
+
+ check_verif_data(self, _metadata);
+}
+
+static void check_prefetch_list(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata,
+ int start_number, int end_number)
+{
+ char digest_list_filename[NAME_MAX + 1], filename[NAME_MAX + 1];
+ char digest_lists[1024] = { 0 }, digest_lists_kernel[1024];
+ char cmd[1024];
+ int i, cmd_len;
+
+ snprintf(filename, sizeof(filename), "file%d", end_number);
+ snprintf(digest_list_filename, sizeof(digest_list_filename),
+ "%d-tlv-digest_list%d", end_number, end_number);
+ ASSERT_EQ(0, create_file(self->base_dirfd, filename,
+ digest_list_filename));
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s/%s",
+ commands_str[DIGEST_CACHE_GET], self->base_dir,
+ filename);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ ASSERT_LT(0, read(self->kernfd, digest_lists_kernel,
+ sizeof(digest_lists_kernel)));
+
+ for (i = start_number; i <= end_number; i++) {
+ if (digest_lists[0])
+ strcat(digest_lists, ",");
+
+ snprintf(digest_list_filename, sizeof(digest_list_filename),
+ "%d-tlv-digest_list%d", i, i);
+ strcat(digest_lists, digest_list_filename);
+ }
+
+ ASSERT_EQ(0, strcmp(digest_lists, digest_lists_kernel));
+
+ ASSERT_EQ(0, unlinkat(self->base_dirfd, filename, 0));
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s",
+ commands_str[DIGEST_CACHE_PUT]);
+ write(self->kernfd, cmd, cmd_len);
+}
+
+static void check_prefetch_list_async(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata)
+{
+ char digest_list_filename[NAME_MAX + 1], filename[NAME_MAX + 1];
+ char digest_lists[1024] = { 0 }, digest_lists_kernel[1024];
+ char cmd[1024];
+ int i, cmd_len;
+
+ for (i = 0; i < NUM_DIGEST_LISTS_PREFETCH; i++) {
+ snprintf(filename, sizeof(filename), "file%d",
+ NUM_DIGEST_LISTS_PREFETCH - 1 - i);
+ snprintf(digest_list_filename, sizeof(digest_list_filename),
+ "%d-tlv-digest_list%d", i, i);
+ ASSERT_EQ(0, create_file(self->base_dirfd, filename,
+ digest_list_filename));
+ }
+
+ /* Do batch of get/put to test the kernel for concurrent requests. */
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s/file|%d|%d",
+ commands_str[DIGEST_CACHE_GET_PUT_ASYNC],
+ self->base_dir, 0, NUM_DIGEST_LISTS_PREFETCH - 1);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ ASSERT_LT(0, read(self->kernfd, digest_lists_kernel,
+ sizeof(digest_lists_kernel)));
+
+ for (i = 0; i < NUM_DIGEST_LISTS_PREFETCH; i++) {
+ if (digest_lists[0])
+ strcat(digest_lists, ",");
+
+ snprintf(digest_list_filename, sizeof(digest_list_filename),
+ "%d-tlv-digest_list%d", i, i);
+ strcat(digest_lists, digest_list_filename);
+ }
+
+ ASSERT_EQ(0, strcmp(digest_lists, digest_lists_kernel));
+}
+
+static void prepare_prefetch(struct _test_data_shared_data *self,
+ struct __test_metadata *_metadata)
+{
+ char digest_list_filename[NAME_MAX + 1];
+ char cmd[1024];
+ int i, cmd_len;
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s",
+ commands_str[DIGEST_CACHE_ENABLE_VERIF],
+ verifs_str[VERIF_PREFETCH]);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ cmd_len = snprintf(cmd, sizeof(cmd), "%s|%s",
+ commands_str[DIGEST_CACHE_SET_VERIF],
+ verifs_str[VERIF_PREFETCH]);
+ ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
+
+ for (i = NUM_DIGEST_LISTS_PREFETCH - 1; i >= 0; i--) {
+ snprintf(digest_list_filename, sizeof(digest_list_filename),
+ "%d-tlv-digest_list%d", i, i);
+ ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd,
+ digest_list_filename, HASH_ALGO_SHA1,
+ i, 1, TLV_NO_FAILURE));
+ }
+
+ ASSERT_EQ(0, fsetxattr(self->digest_lists_dirfd,
+ XATTR_NAME_DIG_PREFETCH, "1", 1, 0));
+}
+
+/*
+ * Verify that digest lists are prefetched when requested, in the correct order
+ * (synchronous version).
+ */
+TEST_F(shared_data, prefetch_sync)
+{
+ int i;
+
+ if (self->no_kprobe)
+ SKIP(return, "CONFIG_DYNAMIC_FTRACE_WITH_ARGS not enabled");
+
+ prepare_prefetch(self, _metadata);
+
+ for (i = 2; i < NUM_DIGEST_LISTS_PREFETCH; i += 3)
+ check_prefetch_list(self, _metadata, i - 2, i);
+}
+
+/*
+ * Verify that digest lists are prefetched when requested, in the correct order
+ * (asynchronous version).
+ */
+TEST_F(shared_data, prefetch_async)
+{
+ if (self->no_kprobe)
+ SKIP(return, "CONFIG_DYNAMIC_FTRACE_WITH_ARGS not enabled");
+
+ prepare_prefetch(self, _metadata);
+
+ check_prefetch_list_async(self, _metadata);
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/digest_cache/common.c b/tools/testing/selftests/digest_cache/common.c
new file mode 100644
index 000000000000..75c0ef50deb8
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/common.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu at huawei.com>
+ *
+ * Add common code for testing the Integrity Digest Cache.
+ */
+
+#include "common.h"
+
+const char *commands_str[DIGEST_CACHE__LAST] = {
+ [DIGEST_CACHE_GET] = "get",
+ [DIGEST_CACHE_LOOKUP] = "lookup",
+ [DIGEST_CACHE_PUT] = "put",
+ [DIGEST_CACHE_ENABLE_VERIF] = "enable_verif",
+ [DIGEST_CACHE_DISABLE_VERIF] = "disable_verif",
+ [DIGEST_CACHE_SET_VERIF] = "set_verif",
+ [DIGEST_CACHE_GET_PUT_ASYNC] = "get_put_async",
+};
+
+const char *const hash_algo_name[HASH_ALGO__LAST] = {
+ [HASH_ALGO_MD4] = "md4",
+ [HASH_ALGO_MD5] = "md5",
+ [HASH_ALGO_SHA1] = "sha1",
+ [HASH_ALGO_RIPE_MD_160] = "rmd160",
+ [HASH_ALGO_SHA256] = "sha256",
+ [HASH_ALGO_SHA384] = "sha384",
+ [HASH_ALGO_SHA512] = "sha512",
+ [HASH_ALGO_SHA224] = "sha224",
+ [HASH_ALGO_RIPE_MD_128] = "rmd128",
+ [HASH_ALGO_RIPE_MD_256] = "rmd256",
+ [HASH_ALGO_RIPE_MD_320] = "rmd320",
+ [HASH_ALGO_WP_256] = "wp256",
+ [HASH_ALGO_WP_384] = "wp384",
+ [HASH_ALGO_WP_512] = "wp512",
+ [HASH_ALGO_TGR_128] = "tgr128",
+ [HASH_ALGO_TGR_160] = "tgr160",
+ [HASH_ALGO_TGR_192] = "tgr192",
+ [HASH_ALGO_SM3_256] = "sm3",
+ [HASH_ALGO_STREEBOG_256] = "streebog256",
+ [HASH_ALGO_STREEBOG_512] = "streebog512",
+ [HASH_ALGO_SHA3_256] = "sha3-256",
+ [HASH_ALGO_SHA3_384] = "sha3-384",
+ [HASH_ALGO_SHA3_512] = "sha3-512",
+};
+
+const int hash_digest_size[HASH_ALGO__LAST] = {
+ [HASH_ALGO_MD4] = MD5_DIGEST_SIZE,
+ [HASH_ALGO_MD5] = MD5_DIGEST_SIZE,
+ [HASH_ALGO_SHA1] = SHA1_DIGEST_SIZE,
+ [HASH_ALGO_RIPE_MD_160] = RMD160_DIGEST_SIZE,
+ [HASH_ALGO_SHA256] = SHA256_DIGEST_SIZE,
+ [HASH_ALGO_SHA384] = SHA384_DIGEST_SIZE,
+ [HASH_ALGO_SHA512] = SHA512_DIGEST_SIZE,
+ [HASH_ALGO_SHA224] = SHA224_DIGEST_SIZE,
+ [HASH_ALGO_RIPE_MD_128] = RMD128_DIGEST_SIZE,
+ [HASH_ALGO_RIPE_MD_256] = RMD256_DIGEST_SIZE,
+ [HASH_ALGO_RIPE_MD_320] = RMD320_DIGEST_SIZE,
+ [HASH_ALGO_WP_256] = WP256_DIGEST_SIZE,
+ [HASH_ALGO_WP_384] = WP384_DIGEST_SIZE,
+ [HASH_ALGO_WP_512] = WP512_DIGEST_SIZE,
+ [HASH_ALGO_TGR_128] = TGR128_DIGEST_SIZE,
+ [HASH_ALGO_TGR_160] = TGR160_DIGEST_SIZE,
+ [HASH_ALGO_TGR_192] = TGR192_DIGEST_SIZE,
+ [HASH_ALGO_SM3_256] = SM3256_DIGEST_SIZE,
+ [HASH_ALGO_STREEBOG_256] = STREEBOG256_DIGEST_SIZE,
+ [HASH_ALGO_STREEBOG_512] = STREEBOG512_DIGEST_SIZE,
+ [HASH_ALGO_SHA3_256] = SHA3_256_DIGEST_SIZE,
+ [HASH_ALGO_SHA3_384] = SHA3_384_DIGEST_SIZE,
+ [HASH_ALGO_SHA3_512] = SHA3_512_DIGEST_SIZE,
+};
+
+const char *verifs_str[] = {
+ [VERIF_FILENAMES] = "kprobe_filenames",
+ [VERIF_NUMBER] = "kprobe_number",
+ [VERIF_PREFETCH] = "kprobe_prefetch",
+};
diff --git a/tools/testing/selftests/digest_cache/common.h b/tools/testing/selftests/digest_cache/common.h
new file mode 100644
index 000000000000..3fd3c249ff6f
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/common.h
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu at huawei.com>
+ *
+ * Header of common.c.
+ */
+
+#ifndef _COMMON_H
+#define _COMMON_H
+#include <linux/types.h>
+
+#include "../../../../include/uapi/linux/hash_info.h"
+
+#define MD5_DIGEST_SIZE 16
+#define SHA1_DIGEST_SIZE 20
+#define RMD160_DIGEST_SIZE 20
+#define SHA256_DIGEST_SIZE 32
+#define SHA384_DIGEST_SIZE 48
+#define SHA512_DIGEST_SIZE 64
+#define SHA224_DIGEST_SIZE 28
+#define RMD128_DIGEST_SIZE 16
+#define RMD256_DIGEST_SIZE 32
+#define RMD320_DIGEST_SIZE 40
+#define WP256_DIGEST_SIZE 32
+#define WP384_DIGEST_SIZE 48
+#define WP512_DIGEST_SIZE 64
+#define TGR128_DIGEST_SIZE 16
+#define TGR160_DIGEST_SIZE 20
+#define TGR192_DIGEST_SIZE 24
+#define SM3256_DIGEST_SIZE 32
+#define STREEBOG256_DIGEST_SIZE 32
+#define STREEBOG512_DIGEST_SIZE 64
+#define SHA3_224_DIGEST_SIZE (224 / 8)
+#define SHA3_256_DIGEST_SIZE (256 / 8)
+#define SHA3_384_DIGEST_SIZE (384 / 8)
+#define SHA3_512_DIGEST_SIZE (512 / 8)
+
+#define DIGEST_CACHE_DIR "/sys/kernel/security/integrity/digest_cache"
+#define DIGEST_CACHE_TEST_INTERFACE "/sys/kernel/security/digest_cache_test"
+#define DIGEST_CACHE_PATH_INTERFACE DIGEST_CACHE_DIR "/default_path"
+#define MAX_DIGEST_SIZE 64
+
+#define MAX_WORKS 21
+
+typedef __u8 u8;
+typedef __u16 u16;
+typedef __u32 u32;
+typedef __s32 s32;
+typedef __u64 u64;
+
+enum commands {
+ DIGEST_CACHE_GET, // args: <path>
+ DIGEST_CACHE_LOOKUP, // args: <algo>|<digest>
+ DIGEST_CACHE_PUT, // args:
+ DIGEST_CACHE_ENABLE_VERIF, // args: <verif name>
+ DIGEST_CACHE_DISABLE_VERIF, // args: <verif name>
+ DIGEST_CACHE_SET_VERIF, // args: <verif name>
+ DIGEST_CACHE_GET_PUT_ASYNC, // args: <path>|<start#>|<end#>
+ DIGEST_CACHE__LAST,
+};
+
+enum tlv_failures { TLV_NO_FAILURE,
+ TLV_FAILURE_ALGO_LEN,
+ TLV_FAILURE_ALGO_MISMATCH,
+ TLV_FAILURE_NUM_DIGESTS,
+ TLV_FAILURE__LAST
+};
+
+enum file_changes { FILE_WRITE,
+ FILE_TRUNCATE,
+ FILE_FTRUNCATE,
+ FILE_UNLINK,
+ FILE_RENAME,
+ FILE_SETXATTR,
+ FILE_REMOVEXATTR,
+ FILE_CHANGE__LAST
+};
+
+enum VERIFS {
+ VERIF_FILENAMES,
+ VERIF_NUMBER,
+ VERIF_PREFETCH,
+ VERIF__LAST
+};
+
+extern const char *commands_str[DIGEST_CACHE__LAST];
+extern const char *const hash_algo_name[HASH_ALGO__LAST];
+extern const int hash_digest_size[HASH_ALGO__LAST];
+extern const char *verifs_str[VERIF__LAST];
+
+#endif /* _COMMON_H */
diff --git a/tools/testing/selftests/digest_cache/common_user.c b/tools/testing/selftests/digest_cache/common_user.c
new file mode 100644
index 000000000000..02f661b942f7
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/common_user.c
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu at huawei.com>
+ *
+ * Add common code in user space for testing the Integrity Digest Cache.
+ */
+
+#include <stddef.h>
+
+#include "common_user.h"
+
+static const char hex_asc[] = "0123456789abcdef";
+
+#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
+#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
+
+static inline char *hex_byte_pack(char *buf, unsigned char byte)
+{
+ *buf++ = hex_asc_hi(byte);
+ *buf++ = hex_asc_lo(byte);
+ return buf;
+}
+
+char *bin2hex(char *dst, const void *src, size_t count)
+{
+ const unsigned char *_src = src;
+
+ while (count--)
+ dst = hex_byte_pack(dst, *_src++);
+ return dst;
+}
diff --git a/tools/testing/selftests/digest_cache/common_user.h b/tools/testing/selftests/digest_cache/common_user.h
new file mode 100644
index 000000000000..8d1f6631ef83
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/common_user.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu at huawei.com>
+ *
+ * Header of common_user.c.
+ */
+
+#include <linux/types.h>
+#include <stddef.h>
+
+#include "common.h"
+
+char *bin2hex(char *dst, const void *src, size_t count);
diff --git a/tools/testing/selftests/digest_cache/config b/tools/testing/selftests/digest_cache/config
new file mode 100644
index 000000000000..7e0ea7d18828
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/config
@@ -0,0 +1,2 @@
+CONFIG_INTEGRITY_DIGEST_CACHE=y
+CONFIG_DYNAMIC_FTRACE=y
diff --git a/tools/testing/selftests/digest_cache/generators.c b/tools/testing/selftests/digest_cache/generators.c
new file mode 100644
index 000000000000..8c36c22e8bcc
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/generators.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu at huawei.com>
+ *
+ * Generate digest lists for testing.
+ */
+
+#include <stddef.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <limits.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/xattr.h>
+#include <asm/byteorder.h>
+
+#include "generators.h"
+#include "../../../../include/uapi/linux/hash_info.h"
+#include "../../../../include/uapi/linux/xattr.h"
+#include "../../../../include/uapi/linux/tlv_digest_list.h"
+#include "../../../../include/uapi/linux/tlv_parser.h"
+
+int gen_tlv_list(int temp_dirfd, char *digest_list_filename,
+ enum hash_algo algo, int start_number, int num_digests,
+ enum tlv_failures failure)
+{
+ __u16 _algo = __cpu_to_be16(algo);
+ __u32 _num_entries = __cpu_to_be32(num_digests);
+ u8 digest[MAX_DIGEST_SIZE] = { 0 };
+ int digest_len = hash_digest_size[algo];
+ int ret, fd, i;
+
+ struct tlv_entry algo_entry = {
+ .field = __cpu_to_be16(DIGEST_LIST_ALGO),
+ .length = __cpu_to_be32(sizeof(_algo)),
+ };
+
+ struct tlv_entry num_entries_entry = {
+ .field = __cpu_to_be16(DIGEST_LIST_NUM_ENTRIES),
+ .length = __cpu_to_be32(sizeof(_num_entries)),
+ };
+
+ struct tlv_entry entry_digest = {
+ .field = __cpu_to_be16(DIGEST_LIST_ENTRY_DIGEST),
+ .length = __cpu_to_be32(digest_len),
+ };
+
+ struct tlv_entry entry_entry = {
+ .field = __cpu_to_be16(DIGEST_LIST_ENTRY),
+ .length = __cpu_to_be32(sizeof(entry_digest) + digest_len),
+ };
+
+ switch (failure) {
+ case TLV_FAILURE_ALGO_LEN:
+ algo_entry.length = algo_entry.length / 2;
+ break;
+ case TLV_FAILURE_ALGO_MISMATCH:
+ _algo = __cpu_to_be16(algo - 1);
+ break;
+ case TLV_FAILURE_NUM_DIGESTS:
+ num_digests = 0;
+ break;
+ default:
+ break;
+ }
+
+ fd = openat(temp_dirfd, digest_list_filename,
+ O_WRONLY | O_CREAT | O_TRUNC, 0600);
+ if (fd == -1)
+ return -errno;
+
+ ret = write(fd, (u8 *)&algo_entry, sizeof(algo_entry));
+ if (ret != sizeof(algo_entry))
+ return -errno;
+
+ ret = write(fd, (u8 *)&_algo, sizeof(_algo));
+ if (ret != sizeof(_algo))
+ return -errno;
+
+ ret = write(fd, (u8 *)&num_entries_entry, sizeof(num_entries_entry));
+ if (ret != sizeof(num_entries_entry))
+ return -errno;
+
+ ret = write(fd, (u8 *)&_num_entries, sizeof(_num_entries));
+ if (ret != sizeof(_num_entries))
+ return -errno;
+
+ *(u32 *)digest = start_number;
+
+ for (i = 0; i < num_digests; i++) {
+ ret = write(fd, (u8 *)&entry_entry, sizeof(entry_entry));
+ if (ret != sizeof(entry_entry))
+ return -errno;
+
+ ret = write(fd, (u8 *)&entry_digest, sizeof(entry_digest));
+ if (ret != sizeof(entry_digest))
+ return -errno;
+
+ ret = write(fd, digest, digest_len);
+ if (ret != digest_len)
+ return -errno;
+
+ (*(u32 *)digest)++;
+ }
+
+ close(fd);
+ return 0;
+}
+
+int create_file(int temp_dirfd, char *filename, char *digest_list_filename)
+{
+ int ret = 0, fd;
+
+ fd = openat(temp_dirfd, filename, O_WRONLY | O_CREAT | O_TRUNC, 0600);
+ if (fd == -1)
+ return -errno;
+
+ if (!digest_list_filename)
+ goto out;
+
+ ret = fsetxattr(fd, XATTR_NAME_DIGEST_LIST, digest_list_filename,
+ strlen(digest_list_filename) + 1, 0);
+ if (ret == -1)
+ ret = -errno;
+out:
+ close(fd);
+ return ret;
+}
diff --git a/tools/testing/selftests/digest_cache/generators.h b/tools/testing/selftests/digest_cache/generators.h
new file mode 100644
index 000000000000..eeeb3c020891
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/generators.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu at huawei.com>
+ *
+ * Header of generators.c.
+ */
+
+#include "common.h"
+#include "common_user.h"
+
+int gen_tlv_list(int temp_dirfd, char *digest_list_filename,
+ enum hash_algo algo, int start_number, int num_digests,
+ enum tlv_failures failure);
+int create_file(int temp_dirfd, char *filename, char *digest_list_filename);
diff --git a/tools/testing/selftests/digest_cache/testmod/Makefile b/tools/testing/selftests/digest_cache/testmod/Makefile
new file mode 100644
index 000000000000..1ba1c7f08658
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/testmod/Makefile
@@ -0,0 +1,16 @@
+KDIR ?= ../../../../..
+
+MODULES = digest_cache_kern.ko
+
+obj-m += digest_cache_kern.o
+
+digest_cache_kern-y := kern.o ../common.o
+
+all:
+ +$(Q)$(MAKE) -C $(KDIR) M=$$PWD modules
+
+clean:
+ +$(Q)$(MAKE) -C $(KDIR) M=$$PWD clean
+
+install: all
+ +$(Q)$(MAKE) -C $(KDIR) M=$$PWD modules_install
diff --git a/tools/testing/selftests/digest_cache/testmod/kern.c b/tools/testing/selftests/digest_cache/testmod/kern.c
new file mode 100644
index 000000000000..4c215fd0b50f
--- /dev/null
+++ b/tools/testing/selftests/digest_cache/testmod/kern.c
@@ -0,0 +1,551 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu at huawei.com>
+ *
+ * Implement the kernel module to interact with the Integrity Digest Cache.
+ */
+
+#define pr_fmt(fmt) "digest_cache TESTMOD: "fmt
+#include <linux/module.h>
+#include <linux/namei.h>
+#include <linux/security.h>
+#include <linux/dynamic_debug.h>
+#include <linux/digest_cache.h>
+#include <linux/kprobes.h>
+#include <linux/cpu.h>
+#include <linux/kernel_read_file.h>
+#include <crypto/hash_info.h>
+
+#include "../common.h"
+
+struct verif {
+ int (*update)(struct file *file);
+ ssize_t (*read)(struct file *file, char __user *buf, size_t datalen,
+ loff_t *ppos);
+ bool enabled;
+};
+
+struct read_work {
+ struct work_struct work;
+ char *path_str;
+ int ret;
+};
+
+static struct dentry *test;
+static struct digest_cache *digest_cache, *found;
+static int cur_verif_index;
+static u8 prefetch_buf[4096];
+static struct read_work w[MAX_WORKS];
+
+static int filenames_update(struct file *file)
+{
+ char *filename = (char *)file->f_path.dentry->d_name.name;
+
+ return digest_cache_verif_set(file, verifs_str[VERIF_FILENAMES],
+ filename, strlen(filename) + 1);
+}
+
+static int number_update(struct file *file)
+{
+ const char *filename = file_dentry(file)->d_name.name;
+ size_t filename_len = strlen(filename);
+ u64 number = U64_MAX;
+ int ret;
+
+ while (filename_len) {
+ if (filename[filename_len - 1] < '0' ||
+ filename[filename_len - 1] > '9')
+ break;
+
+ filename_len--;
+ }
+
+ ret = kstrtoull(filename + filename_len, 10, &number);
+ if (ret < 0) {
+ pr_debug("Failed to convert filename %s into number\n",
+ file_dentry(file)->d_name.name);
+ return ret;
+ }
+
+ return digest_cache_verif_set(file, verifs_str[VERIF_NUMBER], &number,
+ sizeof(number));
+}
+
+static int prefetch_update(struct file *file)
+{
+ char *filename = (char *)file->f_path.dentry->d_name.name;
+ char *start_ptr = prefetch_buf, *end_ptr;
+ int ret;
+
+ ret = digest_cache_verif_set(file, "kprobe_test", "1", 1);
+ if (!ret) {
+ /* Don't include duplicates of requested digest lists. */
+ while ((end_ptr = strchrnul(start_ptr, ','))) {
+ if (end_ptr > start_ptr &&
+ !strncmp(start_ptr, filename, end_ptr - start_ptr))
+ return 0;
+
+ if (!*end_ptr)
+ break;
+
+ start_ptr = end_ptr + 1;
+ }
+ }
+
+ if (prefetch_buf[0])
+ strlcat(prefetch_buf, ",", sizeof(prefetch_buf));
+
+ strlcat(prefetch_buf, filename, sizeof(prefetch_buf));
+ return 0;
+}
+
+static ssize_t filenames_read(struct file *file, char __user *buf,
+ size_t datalen, loff_t *ppos)
+{
+ loff_t _ppos = 0;
+ char *filenames_list;
+
+ filenames_list = digest_cache_verif_get(found ?: digest_cache,
+ verifs_str[VERIF_FILENAMES]);
+ if (!filenames_list)
+ return -ENOENT;
+
+ return simple_read_from_buffer(buf, datalen, &_ppos, filenames_list,
+ strlen(filenames_list) + 1);
+}
+
+static ssize_t number_read(struct file *file, char __user *buf, size_t datalen,
+ loff_t *ppos)
+{
+ loff_t _ppos = 0;
+ u64 *number;
+ char temp[20];
+ ssize_t len;
+
+ number = digest_cache_verif_get(found ?: digest_cache,
+ verifs_str[VERIF_NUMBER]);
+ if (!number)
+ return -ENOENT;
+
+ len = snprintf(temp, sizeof(temp), "%llu", *number);
+
+ return simple_read_from_buffer(buf, datalen, &_ppos, temp, len);
+}
+
+static ssize_t prefetch_read(struct file *file, char __user *buf,
+ size_t datalen, loff_t *ppos)
+{
+ loff_t _ppos = 0;
+ ssize_t ret;
+
+ ret = simple_read_from_buffer(buf, datalen, &_ppos, prefetch_buf,
+ strlen(prefetch_buf) + 1);
+ memset(prefetch_buf, 0, sizeof(prefetch_buf));
+ return ret;
+}
+
+static struct verif verifs_methods[] = {
+ [VERIF_FILENAMES] = { .update = filenames_update,
+ .read = filenames_read },
+ [VERIF_NUMBER] = { .update = number_update, .read = number_read },
+ [VERIF_PREFETCH] = { .update = prefetch_update, .read = prefetch_read },
+};
+
+static void digest_cache_get_put_work(struct work_struct *work)
+{
+ struct read_work *w = container_of(work, struct read_work, work);
+ struct digest_cache *digest_cache;
+ struct path path;
+ struct file *file;
+
+ w->ret = kern_path(w->path_str, 0, &path);
+ if (w->ret < 0)
+ return;
+
+ file = kernel_file_open(&path, O_RDONLY, current_cred());
+ if (IS_ERR(file)) {
+ path_put(&path);
+ return;
+ }
+
+ digest_cache = digest_cache_get(file);
+
+ fput(file);
+ path_put(&path);
+
+ if (!digest_cache) {
+ w->ret = -ENOENT;
+ return;
+ }
+
+ digest_cache_put(digest_cache);
+ w->ret = 0;
+}
+
+static int digest_cache_get_put_async(char *path_str, int start_number,
+ int end_number)
+{
+ int ret = 0, i;
+
+ cpus_read_lock();
+ for (i = start_number; i <= end_number; i++) {
+ w[i].path_str = kasprintf(GFP_KERNEL, "%s%u", path_str, i);
+ if (!w[i].path_str) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ INIT_WORK_ONSTACK(&w[i].work, digest_cache_get_put_work);
+ schedule_work_on(i % num_online_cpus(), &w[i].work);
+ }
+ cpus_read_unlock();
+
+ for (i = start_number; i <= end_number; i++) {
+ if (!w[i].path_str)
+ continue;
+
+ flush_work(&w[i].work);
+ destroy_work_on_stack(&w[i].work);
+ kfree(w[i].path_str);
+ w[i].path_str = NULL;
+ if (!ret)
+ ret = w[i].ret;
+ }
+
+ return ret;
+}
+
+static ssize_t write_request(struct file *file, const char __user *buf,
+ size_t datalen, loff_t *ppos)
+{
+ char *data, *data_ptr, *cmd_str, *path_str, *algo_str, *digest_str;
+ char *verif_name_str, *start_number_str, *end_number_str;
+ u8 digest[64];
+ struct path path;
+ struct file *filp;
+ int ret, cmd, algo, verif_index, start_number, end_number;
+
+ data = memdup_user_nul(buf, datalen);
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ data_ptr = data;
+
+ cmd_str = strsep(&data_ptr, "|");
+ if (!cmd_str) {
+ pr_debug("No command\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ cmd = match_string(commands_str, DIGEST_CACHE__LAST, cmd_str);
+ if (cmd < 0) {
+ pr_err("Unknown command %s\n", cmd_str);
+ ret = -ENOENT;
+ goto out;
+ }
+
+ switch (cmd) {
+ case DIGEST_CACHE_GET:
+ if (found) {
+ if (!IS_ERR(found))
+ digest_cache_put(found);
+
+ found = NULL;
+ }
+
+ path_str = strsep(&data_ptr, "|");
+ if (!path_str) {
+ pr_debug("No path\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = kern_path(path_str, 0, &path);
+ if (ret < 0) {
+ pr_debug("Cannot find file %s\n", path_str);
+ goto out;
+ }
+
+ if (digest_cache) {
+ pr_debug("Digest cache exists, doing a put\n");
+ digest_cache_put(digest_cache);
+ }
+
+ filp = kernel_file_open(&path, O_RDONLY, current_cred());
+ if (IS_ERR(filp)) {
+ pr_debug("Cannot open file %s\n", path_str);
+ path_put(&path);
+ goto out;
+ }
+
+ digest_cache = digest_cache_get(filp);
+ ret = digest_cache ? 0 : -ENOENT;
+ pr_debug("digest cache get %s, ret: %d\n", path_str, ret);
+ fput(filp);
+ path_put(&path);
+ break;
+ case DIGEST_CACHE_LOOKUP:
+ if (found) {
+ if (!IS_ERR(found))
+ digest_cache_put(found);
+
+ found = NULL;
+ }
+
+ if (!digest_cache) {
+ pr_debug("No digest cache\n");
+ ret = -ENOENT;
+ goto out;
+ }
+
+ path_str = strsep(&data_ptr, "|");
+ if (!path_str) {
+ pr_debug("No path\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ algo_str = strsep(&data_ptr, ":");
+ digest_str = data_ptr;
+
+ if (!algo_str || !digest_str) {
+ pr_debug("No algo or digest\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ algo = match_string(hash_algo_name, HASH_ALGO__LAST, algo_str);
+ if (algo < 0) {
+ pr_err("Unknown algorithm %s", algo_str);
+ ret = -ENOENT;
+ goto out;
+ }
+
+ ret = hex2bin(digest, digest_str, hash_digest_size[algo]);
+ if (ret < 0) {
+ pr_debug("Invalid digest %s\n", digest_str);
+ goto out;
+ }
+
+ ret = kern_path(path_str, 0, &path);
+ if (ret < 0) {
+ pr_debug("Cannot find file %s\n", path_str);
+ goto out;
+ }
+
+ ret = -ENOENT;
+
+ found = digest_cache_lookup(path.dentry, digest_cache, digest,
+ algo);
+ path_put(&path);
+ if (found && !IS_ERR(found))
+ ret = 0;
+
+ pr_debug("%s:%s lookup %s, ret: %d\n", algo_str, digest_str,
+ path_str, ret);
+ break;
+ case DIGEST_CACHE_PUT:
+ if (digest_cache) {
+ digest_cache_put(digest_cache);
+ digest_cache = NULL;
+ }
+
+ if (found) {
+ if (!IS_ERR(found))
+ digest_cache_put(found);
+
+ found = NULL;
+ }
+ ret = 0;
+ pr_debug("digest cache put, ret: %d\n", ret);
+ break;
+ case DIGEST_CACHE_ENABLE_VERIF:
+ case DIGEST_CACHE_DISABLE_VERIF:
+ if (!IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_ARGS)) {
+ ret = -EOPNOTSUPP;
+ goto out;
+ }
+
+ memset(prefetch_buf, 0, sizeof(prefetch_buf));
+ fallthrough;
+ case DIGEST_CACHE_SET_VERIF:
+ verif_name_str = strsep(&data_ptr, "|");
+ if (!verif_name_str) {
+ pr_debug("No verifier name\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ verif_index = match_string(verifs_str, ARRAY_SIZE(verifs_str),
+ verif_name_str);
+ if (verif_index < 0) {
+ pr_err("Unknown verifier name %s\n", verif_name_str);
+ ret = -ENOENT;
+ goto out;
+ }
+
+ if (cmd == DIGEST_CACHE_ENABLE_VERIF)
+ verifs_methods[verif_index].enabled = true;
+ else if (cmd == DIGEST_CACHE_DISABLE_VERIF)
+ verifs_methods[verif_index].enabled = false;
+ else
+ cur_verif_index = verif_index;
+
+ ret = 0;
+ pr_debug("digest cache %s %s, ret: %d\n", cmd_str,
+ verif_name_str, ret);
+ break;
+ case DIGEST_CACHE_GET_PUT_ASYNC:
+ path_str = strsep(&data_ptr, "|");
+ if (!path_str) {
+ pr_debug("No path\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ start_number_str = strsep(&data_ptr, "|");
+ if (!start_number_str) {
+ pr_debug("No start number\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = kstrtoint(start_number_str, 10, &start_number);
+ if (ret < 0) {
+ pr_debug("Invalid start number %s\n", start_number_str);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ end_number_str = strsep(&data_ptr, "|");
+ if (!end_number_str) {
+ pr_debug("No end number\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = kstrtoint(end_number_str, 10, &end_number);
+ if (ret < 0) {
+ pr_debug("Invalid end number %s\n", end_number_str);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (end_number - start_number >= MAX_WORKS) {
+ pr_debug("Too many works (%d), max %d\n",
+ end_number - start_number, MAX_WORKS - 1);
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = digest_cache_get_put_async(path_str, start_number,
+ end_number);
+ pr_debug("digest cache %s on %s, start: %d, end: %d, ret: %d\n",
+ cmd_str, path_str, start_number, end_number, ret);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+out:
+ kfree(data);
+ return ret ?: datalen;
+}
+
+static ssize_t read_request(struct file *file, char __user *buf, size_t datalen,
+ loff_t *ppos)
+{
+ return verifs_methods[cur_verif_index].read(file, buf, datalen, ppos);
+}
+
+static const struct file_operations digest_cache_test_ops = {
+ .open = generic_file_open,
+ .write = write_request,
+ .read = read_request,
+ .llseek = generic_file_llseek,
+};
+
+static int __kprobes kernel_post_read_file_hook(struct kprobe *p,
+ struct pt_regs *regs)
+{
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_ARGS
+ struct file *file = (struct file *)regs_get_kernel_argument(regs, 0);
+ enum kernel_read_file_id id = regs_get_kernel_argument(regs, 3);
+#else
+ struct file *file = NULL;
+ enum kernel_read_file_id id = READING_UNKNOWN;
+#endif
+ int ret, i;
+
+ if (id != READING_DIGEST_LIST)
+ return 0;
+
+ for (i = 0; i < ARRAY_SIZE(verifs_methods); i++) {
+ if (!verifs_methods[i].enabled)
+ continue;
+
+ ret = verifs_methods[i].update(file);
+ if (ret < 0)
+ return 0;
+ }
+
+ return 0;
+}
+
+static struct kprobe kp = {
+ .symbol_name = "security_kernel_post_read_file",
+};
+
+static int __init digest_cache_test_init(void)
+{
+ int ret;
+
+ kp.pre_handler = kernel_post_read_file_hook;
+
+ if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_ARGS)) {
+ ret = register_kprobe(&kp);
+ if (ret < 0) {
+ pr_err("register_kprobe failed, returned %d\n", ret);
+ return ret;
+ }
+ }
+
+ test = securityfs_create_file("digest_cache_test", 0660, NULL, NULL,
+ &digest_cache_test_ops);
+ if (IS_ERR(test)) {
+ ret = PTR_ERR(test);
+ goto out_kprobe;
+ }
+
+ return 0;
+out_kprobe:
+ if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_ARGS))
+ unregister_kprobe(&kp);
+ return ret;
+}
+
+static void __exit digest_cache_test_fini(void)
+{
+ if (digest_cache)
+ digest_cache_put(digest_cache);
+
+ if (found) {
+ if (!IS_ERR(found))
+ digest_cache_put(found);
+
+ found = NULL;
+ }
+
+ securityfs_remove(test);
+ if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_ARGS))
+ unregister_kprobe(&kp);
+ pr_debug("kprobe at %p unregistered\n", kp.addr);
+}
+
+module_init(digest_cache_test_init);
+module_exit(digest_cache_test_fini);
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Kernel module for testing Integrity Digest Cache");
--
2.47.0.118.gfd3785337b
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