Re: [PATCH v4 13/14] selftests/digest_cache: Add selftests for digest_cache LSM

Roberto Sassu
2024-04-16T10:39:49Z

On 4/15/2024 9:47 PM, Jarkko Sakkinen wrote:
> On Mon Apr 15, 2024 at 5:24 PM EEST, Roberto Sassu wrote:
>> From: Roberto Sassu <roberto.sassu@huawei.com>
>>
>> Add tests to verify the correctness of the digest_cache LSM, in all_test.c.
>>
>> Add the kernel module digest_cache_kern.ko, to let all_test call the API
>> of the digest_cache LSM through the newly introduced digest_cache_test file
>> in securityfs.
>>
>> Test coverage information:
>>
>> File 'security/digest_cache/notifier.c'
>> Lines executed:100.00% of 31
>> File 'security/digest_cache/reset.c'
>> Lines executed:98.36% of 61
>> File 'security/digest_cache/main.c'
>> Lines executed:90.29% of 206
>> File 'security/digest_cache/modsig.c'
>> Lines executed:42.86% of 21
>> File 'security/digest_cache/htable.c'
>> Lines executed:93.02% of 86
>> File 'security/digest_cache/populate.c'
>> Lines executed:92.86% of 56
>> File 'security/digest_cache/verif.c'
>> Lines executed:89.74% of 39
>> File 'security/digest_cache/dir.c'
>> Lines executed:90.62% of 96
>> File 'security/digest_cache/secfs.c'
>> Lines executed:57.14% of 21
>> File 'security/digest_cache/parsers/tlv.c'
>> Lines executed:79.75% of 79
>> File 'security/digest_cache/parsers/rpm.c'
>> Lines executed:88.46% of 78
>>
>> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
>> ---
>> MAINTAINERS | 1 +
>> 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 | 815 ++++++++++++++++++
>> tools/testing/selftests/digest_cache/common.c | 78 ++
>> tools/testing/selftests/digest_cache/common.h | 135 +++
>> .../selftests/digest_cache/common_user.c | 47 +
>> .../selftests/digest_cache/common_user.h | 17 +
>> tools/testing/selftests/digest_cache/config | 1 +
>> .../selftests/digest_cache/generators.c | 248 ++++++
>> .../selftests/digest_cache/generators.h | 19 +
>> .../selftests/digest_cache/testmod/Makefile | 16 +
>> .../selftests/digest_cache/testmod/kern.c | 564 ++++++++++++
>> 14 files changed, 1969 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/MAINTAINERS b/MAINTAINERS
>> index 72801a88449c..d7f700da009e 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -6198,6 +6198,7 @@ M: Roberto Sassu <roberto.sassu@huawei.com>
>> L: linux-security-module@vger.kernel.org
>> S: Maintained
>> F: security/digest_cache/
>> +F: tools/testing/selftests/digest_cache/
>>
> A common convetion is to have one patch with MAINTAINERS update in the
> tail. This is now sprinkled to multiple patches which is not good.

Ok.

Thanks

Roberto

>> DIGITEQ AUTOMOTIVE MGB4 V4L2 DRIVER
>> M: Martin Tuma <martin.tuma@digiteqautomotive.com>
>> diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
>> index 15b6a111c3be..3c5965a62d28 100644
>> --- a/tools/testing/selftests/Makefile
>> +++ b/tools/testing/selftests/Makefile
>> @@ -13,6 +13,7 @@ TARGETS += core
>> TARGETS += cpufreq
>> TARGETS += cpu-hotplug
>> TARGETS += damon
>> +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..6b1e0d3c08cf
>> --- /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)
>> + 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..9f45e522c43c
>> --- /dev/null
>> +++ b/tools/testing/selftests/digest_cache/all_test.c
>> @@ -0,0 +1,815 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
>> + *
>> + * Author: Roberto Sassu <roberto.sassu@huawei.com>
>> + *
>> + * Implement the tests of the digest_cache LSM.
>> + */
>> +
>> +#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;
>> + int notify_inodesfd;
>> +};
>> +
>> +FIXTURE_SETUP(shared_data)
>> +{
>> + char cmd[1024];
>> + int 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 notify inodes interface. */
>> + self->notify_inodesfd = open(DIGEST_CACHE_NOTIFY_INODES_INTERFACE,
>> + O_RDWR, 0600);
>> + ASSERT_NE(-1, self->notify_inodesfd);
>> +
>> + /* 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]);
>> + ASSERT_EQ(cmd_len, write(self->kernfd, cmd, cmd_len));
>> + }
>> +}
>> +
>> +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 notify inodes interface. */
>> + close(self->notify_inodesfd);
>> +
>> + /* 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)
>> +{
>> + 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, 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;
>> +
>> + 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 enum pgp_algos get_pgp_algo(enum hash_algo algo)
>> +{
>> + unsigned long i;
>> +
>> + for (i = DIGEST_ALGO_MD5; i < ARRAY_SIZE(pgp_algo_mapping); i++)
>> + if (pgp_algo_mapping[i] == algo)
>> + return i;
>> +
>> + return DIGEST_ALGO_SHA224 + 1;
>> +}
>> +
>> +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));
>> + } else if (!strncmp(digest_list_filename, "rpm-", 4)) {
>> + enum pgp_algos pgp_algo = get_pgp_algo(algo);
>> +
>> + if (pgp_algo == DIGEST_ALGO_SHA224 + 1)
>> + return;
>> +
>> + ASSERT_EQ(0, gen_rpm_list(self->digest_lists_dirfd,
>> + digest_list_filename, algo, pgp_algo,
>> + start_number, num_digests,
>> + (enum rpm_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);
>> +}
>> +
>> +/*
>> + * Verify that the rpm digest list parser returns success on well-formatted
>> + * digest lists, for each defined hash algorithm.
>> + */
>> +TEST_F(shared_data, rpm_parser_ok)
>> +{
>> + enum hash_algo algo;
>> +
>> + /* Test every known algorithm. */
>> + for (algo = 0; algo < HASH_ALGO__LAST; algo++)
>> + test_parser(self, _metadata, "rpm-digest_list", "file", algo,
>> + 0, 5, RPM_NO_FAILURE);
>> +}
>> +
>> +/*
>> + * Verify that the rpm digest list parser returns failure on invalid digest
>> + * lists.
>> + */
>> +TEST_F(shared_data, rpm_parser_error)
>> +{
>> + enum rpm_failures failure;
>> +
>> + /* Test every failure. */
>> + for (failure = 0; failure < RPM_FAILURE__LAST; failure++)
>> + test_parser(self, _metadata, "rpm-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 notify_inode_init(struct _test_data_shared_data *self,
>> + struct __test_metadata *_metadata)
>> +{
>> + /* Clear buffer. */
>> + ASSERT_EQ(1, write(self->notify_inodesfd, "1", 1));
>> +}
>> +
>> +static void notify_inodes_check(struct _test_data_shared_data *self,
>> + struct __test_metadata *_metadata,
>> + char *filenames)
>> +{
>> + char notify_inodes_buf[1024] = { 0 };
>> + char notify_inodes_buf_kernel[1024] = { 0 };
>> + char *filename, *filenames_copy, *buf_ptr = notify_inodes_buf;
>> + struct stat st;
>> + int fd;
>> +
>> + ASSERT_LT(0, read(self->notify_inodesfd, notify_inodes_buf_kernel,
>> + sizeof(notify_inodes_buf_kernel)));
>> +
>> + filenames_copy = strdup(filenames);
>> + ASSERT_NE(NULL, filenames_copy);
>> +
>> + while ((filename = strsep(&filenames_copy, ","))) {
>> + fd = openat(self->base_dirfd, filename, O_RDONLY);
>> + ASSERT_NE(-1, fd);
>> + ASSERT_EQ(0, fstat(fd, &st));
>> + close(fd);
>> +
>> + buf_ptr += snprintf(buf_ptr,
>> + sizeof(notify_inodes_buf) -
>> + (buf_ptr - notify_inodes_buf), "%s%lu",
>> + notify_inodes_buf[0] ? "," : "", st.st_ino);
>> + }
>> +
>> + free(filenames_copy);
>> +
>> + ASSERT_EQ(0, strcmp(notify_inodes_buf, notify_inodes_buf_kernel));
>> +}
>> +
>> +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));
>> +
>> + notify_inode_init(self, _metadata);
>> +
>> + 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));
>> +
>> + notify_inodes_check(self, _metadata, "file");
>> + return;
>> + default:
>> + break;
>> + }
>> +
>> + ASSERT_NE(0, query_test(self->kernfd, self->base_dir, "file",
>> + HASH_ALGO_SHA1, 0, 1));
>> +
>> + notify_inodes_check(self, _metadata, "file");
>> +}
>> +
>> +/*
>> + * 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);
>> +}
>> +
>> +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)
>> +{
>> + 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;
>> + }
>> + }
>> +
>> + ASSERT_EQ(expected_ret, query_test(self->kernfd, self->base_dir,
>> + "file", 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 digest_list_filename[NAME_MAX + 1];
>> + int i, removed[10];
>> +
>> + for (i = 0; i < 10; i++) {
>> + snprintf(digest_list_filename, sizeof(digest_list_filename),
>> + "tlv-digest_list%d", 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", NULL));
>> + /* The second file is to have duplicate notifications (file and dir). */
>> + ASSERT_EQ(0, create_file(self->base_dirfd, "file2",
>> + "tlv-digest_list7"));
>> + /* The query adds file2 inode to the file digest cache notif. list. */
>> + ASSERT_NE(0, query_test(self->kernfd, self->base_dir, "file2",
>> + HASH_ALGO_SHA1, 0, 1));
>> +
>> + query_test_with_failures(self, _metadata, 0, 10, removed, 0);
>> +
>> + notify_inode_init(self, _metadata);
>> + ASSERT_EQ(0, unlinkat(self->digest_lists_dirfd, "tlv-digest_list7", 0));
>> + /* File notification comes before directory notification. */
>> + notify_inodes_check(self, _metadata, "file2,file");
>> +
>> + removed[0] = 7;
>> +
>> + query_test_with_failures(self, _metadata, 0, 10, removed, 1);
>> +
>> + notify_inode_init(self, _metadata);
>> + ASSERT_EQ(0, renameat(self->digest_lists_dirfd, "tlv-digest_list6",
>> + self->base_dirfd, "tlv-digest_list6"));
>> + notify_inodes_check(self, _metadata, "file");
>> +
>> + removed[1] = 6;
>> +
>> + query_test_with_failures(self, _metadata, 0, 10, removed, 2);
>> +
>> + notify_inode_init(self, _metadata);
>> + ASSERT_EQ(0, renameat(self->base_dirfd, "tlv-digest_list6",
>> + self->digest_lists_dirfd, "tlv-digest_list6"));
>> + notify_inodes_check(self, _metadata, "file");
>> +
>> + query_test_with_failures(self, _metadata, 0, 10, removed, 1);
>> +
>> + notify_inode_init(self, _metadata);
>> + ASSERT_EQ(0, gen_tlv_list(self->digest_lists_dirfd, "tlv-digest_list10",
>> + HASH_ALGO_SHA1, 10, 1, TLV_NO_FAILURE));
>> + notify_inodes_check(self, _metadata, "file");
>> +
>> + 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));
>> + }
>> +
>> + ASSERT_EQ(0, create_file(self->base_dirfd, "file", NULL));
>> +
>> + for (i = 0; i < 11; i++) {
>> + 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)
>> +{
>> + 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)
>> +{
>> + 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], digest_lists_kernel[1024] = { 0 };
>> + 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, sizeof(digest_lists)));
>> +
>> + for (i = start_number; i <= end_number; i++) {
>> + if (digest_lists_kernel[0])
>> + strcat(digest_lists_kernel, ",");
>> +
>> + snprintf(digest_list_filename, sizeof(digest_list_filename),
>> + "%d-tlv-digest_list%d", i, i);
>> + strcat(digest_lists_kernel, 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], digest_lists_kernel[1024] = { 0 };
>> + 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, sizeof(digest_lists)));
>> +
>> + for (i = 0; i < NUM_DIGEST_LISTS_PREFETCH; i++) {
>> + if (digest_lists_kernel[0])
>> + strcat(digest_lists_kernel, ",");
>> +
>> + snprintf(digest_list_filename, sizeof(digest_list_filename),
>> + "%d-tlv-digest_list%d", i, i);
>> + strcat(digest_lists_kernel, 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;
>> +
>> + 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)
>> +{
>> + 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..2123f7d937ce
>> --- /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@huawei.com>
>> + *
>> + * Add common code for testing the digest_cache LSM.
>> + */
>> +
>> +#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] = "filenames",
>> + [VERIF_NUMBER] = "number",
>> + [VERIF_PREFETCH] = "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..e52e4b137807
>> --- /dev/null
>> +++ b/tools/testing/selftests/digest_cache/common.h
>> @@ -0,0 +1,135 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
>> + *
>> + * Author: Roberto Sassu <roberto.sassu@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_TEST_INTERFACE "/sys/kernel/security/digest_cache_test"
>> +#define DIGEST_CACHE_PATH_INTERFACE "/sys/kernel/security/digest_cache_path"
>> +#define DIGEST_CACHE_NOTIFY_INODES_INTERFACE \
>> + "/sys/kernel/security/digest_cache_notify_inodes"
>> +#define MAX_DIGEST_SIZE 64
>> +
>> +#define RPMTAG_FILEDIGESTS 1035
>> +#define RPMTAG_FILEDIGESTALGO 5011
>> +
>> +#define RPM_INT32_TYPE 4
>> +#define RPM_STRING_ARRAY_TYPE 8
>> +
>> +#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_HDR_LEN,
>> + TLV_FAILURE_ALGO_MISMATCH,
>> + TLV_FAILURE_NUM_DIGESTS,
>> + TLV_FAILURE__LAST
>> +};
>> +
>> +enum rpm_failures { RPM_NO_FAILURE,
>> + RPM_FAILURE_WRONG_MAGIC,
>> + RPM_FAILURE_BAD_DATA_OFFSET,
>> + RPM_FAILURE_WRONG_TAGS,
>> + RPM_FAILURE_WRONG_DIGEST_COUNT,
>> + RPM_FAILURE_DIGEST_WRONG_TYPE,
>> + RPM_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
>> +};
>> +
>> +enum pgp_algos {
>> + DIGEST_ALGO_MD5 = 1,
>> + DIGEST_ALGO_SHA1 = 2,
>> + DIGEST_ALGO_RMD160 = 3,
>> + /* 4, 5, 6, and 7 are reserved. */
>> + DIGEST_ALGO_SHA256 = 8,
>> + DIGEST_ALGO_SHA384 = 9,
>> + DIGEST_ALGO_SHA512 = 10,
>> + DIGEST_ALGO_SHA224 = 11,
>> +};
>> +
>> +struct rpm_hdr {
>> + u32 magic;
>> + u32 reserved;
>> + u32 tags;
>> + u32 datasize;
>> +} __attribute__ ((__packed__));
>> +
>> +struct rpm_entryinfo {
>> + s32 tag;
>> + u32 type;
>> + s32 offset;
>> + u32 count;
>> +} __attribute__ ((__packed__));
>> +
>> +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..1bacadad6b6a
>> --- /dev/null
>> +++ b/tools/testing/selftests/digest_cache/common_user.c
>> @@ -0,0 +1,47 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
>> + *
>> + * Author: Roberto Sassu <roberto.sassu@huawei.com>
>> + *
>> + * Add common code in user space for testing the digest_cache LSM.
>> + */
>> +
>> +#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]
>> +
>> +const enum hash_algo pgp_algo_mapping[DIGEST_ALGO_SHA224 + 1] = {
>> + [DIGEST_ALGO_MD5] = HASH_ALGO_MD5,
>> + [DIGEST_ALGO_SHA1] = HASH_ALGO_SHA1,
>> + [DIGEST_ALGO_RMD160] = HASH_ALGO_RIPE_MD_160,
>> + [4] = HASH_ALGO__LAST,
>> + [5] = HASH_ALGO__LAST,
>> + [6] = HASH_ALGO__LAST,
>> + [7] = HASH_ALGO__LAST,
>> + [DIGEST_ALGO_SHA256] = HASH_ALGO_SHA256,
>> + [DIGEST_ALGO_SHA384] = HASH_ALGO_SHA384,
>> + [DIGEST_ALGO_SHA512] = HASH_ALGO_SHA512,
>> + [DIGEST_ALGO_SHA224] = HASH_ALGO_SHA224,
>> +};
>> +
>> +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..4eef52cc5c27
>> --- /dev/null
>> +++ b/tools/testing/selftests/digest_cache/common_user.h
>> @@ -0,0 +1,17 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
>> + *
>> + * Author: Roberto Sassu <roberto.sassu@huawei.com>
>> + *
>> + * Header of common_user.c.
>> + */
>> +
>> +#include <linux/types.h>
>> +#include <stddef.h>
>> +
>> +#include "common.h"
>> +
>> +extern const enum hash_algo pgp_algo_mapping[DIGEST_ALGO_SHA224 + 1];
>> +
>> +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..075a06cc4f8e
>> --- /dev/null
>> +++ b/tools/testing/selftests/digest_cache/config
>> @@ -0,0 +1 @@
>> +CONFIG_SECURITY_DIGEST_CACHE=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..c7791a3589f2
>> --- /dev/null
>> +++ b/tools/testing/selftests/digest_cache/generators.c
>> @@ -0,0 +1,248 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
>> + *
>> + * Author: Roberto Sassu <roberto.sassu@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)
>> +{
>> + u64 _algo = __cpu_to_be64(algo);
>> + u8 digest[MAX_DIGEST_SIZE] = { 0 };
>> + int digest_len = hash_digest_size[algo];
>> + int digest_len_to_copy = digest_len;
>> + int ret, fd, i;
>> +
>> + struct tlv_data_entry algo_entry = {
>> + .field = __cpu_to_be64(DIGEST_LIST_ALGO),
>> + .length = __cpu_to_be64(sizeof(_algo)),
>> + };
>> +
>> + struct tlv_data_entry entry_digest = {
>> + .field = __cpu_to_be64(DIGEST_LIST_ENTRY_DIGEST),
>> + .length = __cpu_to_be64(digest_len),
>> + };
>> +
>> + struct tlv_hdr entry_hdr = {
>> + .data_type = __cpu_to_be64(DIGEST_LIST_ENTRY_DATA),
>> + ._reserved = 0,
>> + .num_entries = __cpu_to_be64(1),
>> + .total_len = __cpu_to_be64(sizeof(entry_digest) + digest_len),
>> + };
>> +
>> + struct tlv_data_entry entry_entry = {
>> + .field = __cpu_to_be64(DIGEST_LIST_ENTRY),
>> + .length = __cpu_to_be64(sizeof(entry_hdr) +
>> + __be64_to_cpu(entry_hdr.total_len)),
>> + };
>> +
>> + struct tlv_hdr hdr = {
>> + .data_type = __cpu_to_be64(DIGEST_LIST_FILE),
>> + ._reserved = 0,
>> + .num_entries = __cpu_to_be64(1 + num_digests),
>> + .total_len = __cpu_to_be64(sizeof(algo_entry) +
>> + __be64_to_cpu(algo_entry.length) +
>> + num_digests * (sizeof(entry_entry) +
>> + __be64_to_cpu(entry_entry.length)))
>> + };
>> +
>> + switch (failure) {
>> + case TLV_FAILURE_ALGO_LEN:
>> + algo_entry.length = algo_entry.length / 2;
>> + break;
>> + case TLV_FAILURE_HDR_LEN:
>> + hdr.total_len--;
>> + break;
>> + case TLV_FAILURE_ALGO_MISMATCH:
>> + _algo = __cpu_to_be64(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 *)&hdr, sizeof(hdr));
>> + if (ret != sizeof(hdr))
>> + 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;
>> +
>> + *(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_hdr, sizeof(entry_hdr));
>> + if (ret != sizeof(entry_hdr))
>> + return -errno;
>> +
>> + ret = write(fd, (u8 *)&entry_digest, sizeof(entry_digest));
>> + if (ret != sizeof(entry_digest))
>> + return -errno;
>> +
>> + ret = write(fd, digest, digest_len_to_copy);
>> + if (ret != digest_len_to_copy)
>> + return -errno;
>> +
>> + (*(u32 *)digest)++;
>> + }
>> +
>> + close(fd);
>> + return 0;
>> +}
>> +
>> +int gen_rpm_list(int temp_dirfd, char *digest_list_filename,
>> + enum hash_algo algo, enum pgp_algos pgp_algo, int start_number,
>> + int num_digests, enum rpm_failures failure)
>> +{
>> + u32 _pgp_algo = __cpu_to_be32(pgp_algo);
>> + u8 digest[MAX_DIGEST_SIZE] = { 0 };
>> + char digest_str[MAX_DIGEST_SIZE * 2 + 1];
>> + struct rpm_hdr hdr;
>> + struct rpm_entryinfo algo_entry, digest_entry;
>> + int digest_len = hash_digest_size[algo];
>> + int ret, fd, d_len, i;
>> +
>> + d_len = hash_digest_size[algo] * 2 + 1;
>> +
>> + hdr.magic = __cpu_to_be32(0x8eade801);
>> + hdr.reserved = 0;
>> + hdr.tags = __cpu_to_be32(1);
>> +
>> + /*
>> + * Skip the algo section, to ensure that the parser recognizes MD5 as
>> + * the default hash algorithm.
>> + */
>> + if (algo != HASH_ALGO_MD5)
>> + hdr.tags = __cpu_to_be32(2);
>> +
>> + hdr.datasize = __cpu_to_be32(d_len * num_digests);
>> +
>> + if (algo != HASH_ALGO_MD5)
>> + hdr.datasize = __cpu_to_be32(sizeof(u32) + d_len * num_digests);
>> +
>> + digest_entry.tag = __cpu_to_be32(RPMTAG_FILEDIGESTS);
>> + digest_entry.type = __cpu_to_be32(RPM_STRING_ARRAY_TYPE);
>> + digest_entry.offset = 0;
>> + digest_entry.count = __cpu_to_be32(num_digests);
>> +
>> + algo_entry.tag = __cpu_to_be32(RPMTAG_FILEDIGESTALGO);
>> + algo_entry.type = __cpu_to_be32(RPM_INT32_TYPE);
>> + algo_entry.offset = __cpu_to_be32(d_len * num_digests);
>> + algo_entry.count = __cpu_to_be32(1);
>> +
>> + switch (failure) {
>> + case RPM_FAILURE_WRONG_MAGIC:
>> + hdr.magic++;
>> + break;
>> + case RPM_FAILURE_BAD_DATA_OFFSET:
>> + algo_entry.offset = __cpu_to_be32(UINT_MAX);
>> + break;
>> + case RPM_FAILURE_WRONG_TAGS:
>> + hdr.tags = __cpu_to_be32(2 + 10);
>> + break;
>> + case RPM_FAILURE_WRONG_DIGEST_COUNT:
>> + /* We need to go beyond the algorithm, to fail. */
>> + digest_entry.count = __cpu_to_be32(num_digests + 5);
>> + break;
>> + case RPM_FAILURE_DIGEST_WRONG_TYPE:
>> + digest_entry.type = __cpu_to_be32(RPM_INT32_TYPE);
>> + 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 *)&hdr, sizeof(hdr));
>> + if (ret != sizeof(hdr))
>> + return -errno;
>> +
>> + if (algo != HASH_ALGO_MD5) {
>> + ret = write(fd, (u8 *)&algo_entry, sizeof(algo_entry));
>> + if (ret != sizeof(algo_entry))
>> + return -errno;
>> + }
>> +
>> + ret = write(fd, (u8 *)&digest_entry, sizeof(digest_entry));
>> + if (ret != sizeof(digest_entry))
>> + return -errno;
>> +
>> + *(u32 *)digest = start_number;
>> +
>> + for (i = 0; i < num_digests; i++) {
>> + bin2hex(digest_str, digest, digest_len);
>> +
>> + ret = write(fd, (u8 *)digest_str, d_len);
>> + if (ret != d_len)
>> + return -errno;
>> +
>> + (*(u32 *)digest)++;
>> + }
>> +
>> + if (algo != HASH_ALGO_MD5) {
>> + ret = write(fd, (u8 *)&_pgp_algo, sizeof(_pgp_algo));
>> + if (ret != sizeof(_pgp_algo))
>> + return -errno;
>> + }
>> +
>> + 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..1c83e531b799
>> --- /dev/null
>> +++ b/tools/testing/selftests/digest_cache/generators.h
>> @@ -0,0 +1,19 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/*
>> + * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
>> + *
>> + * Author: Roberto Sassu <roberto.sassu@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 gen_rpm_list(int temp_dirfd, char *digest_list_filename,
>> + enum hash_algo algo, enum pgp_algos pgp_algo, int start_number,
>> + int num_digests, enum rpm_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..7215ef638e66
>> --- /dev/null
>> +++ b/tools/testing/selftests/digest_cache/testmod/kern.c
>> @@ -0,0 +1,564 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
>> + *
>> + * Author: Roberto Sassu <roberto.sassu@huawei.com>
>> + *
>> + * Implement the kernel module to interact with the digest_cache LSM.
>> + */
>> +
>> +#define pr_fmt(fmt) "DIGEST CACHE TEST: "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, *notify_inodes;
>> +static struct digest_cache *digest_cache;
>> +static digest_cache_found_t found;
>> +static int cur_verif_index;
>> +static u8 prefetch_buf[4096];
>> +static u8 notify_inodes_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, "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, "number", &number, sizeof(number));
>> +}
>> +
>> +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_from_found_t(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_from_found_t(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 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, "probe_digest_cache", "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 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 int test_digest_cache_change(struct notifier_block *nb,
>> + unsigned long event, void *data)
>> +{
>> + struct digest_cache_event_data *event_data = data;
>> + char i_ino_str[10];
>> +
>> + if (event != DIGEST_CACHE_RESET)
>> + return NOTIFY_DONE;
>> +
>> + if (notify_inodes_buf[0])
>> + strlcat(notify_inodes_buf, ",", sizeof(notify_inodes_buf));
>> +
>> + snprintf(i_ino_str, sizeof(i_ino_str), "%lu", event_data->inode->i_ino);
>> + strlcat(notify_inodes_buf, i_ino_str, sizeof(notify_inodes_buf));
>> + return 0;
>> +}
>> +
>> +static struct notifier_block digest_cache_notifier = {
>> + .notifier_call = test_digest_cache_change,
>> +};
>> +
>> +static ssize_t write_notify_inodes(struct file *file, const char __user *buf,
>> + size_t datalen, loff_t *ppos)
>> +{
>> + memset(notify_inodes_buf, 0, sizeof(notify_inodes_buf));
>> + return datalen;
>> +}
>> +
>> +static ssize_t read_notify_inodes(struct file *file, char __user *buf,
>> + size_t datalen, loff_t *ppos)
>> +{
>> + loff_t _ppos = 0;
>> +
>> + return simple_read_from_buffer(buf, datalen, &_ppos, notify_inodes_buf,
>> + strlen(notify_inodes_buf) + 1);
>> +}
>> +
>> +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;
>> +
>> + w->ret = kern_path(w->path_str, 0, &path);
>> + if (w->ret < 0)
>> + return;
>> +
>> + digest_cache = digest_cache_get(path.dentry);
>> +
>> + 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;
>> + 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:
>> + found = 0UL;
>> +
>> + 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);
>> + }
>> +
>> + digest_cache = digest_cache_get(path.dentry);
>> + ret = digest_cache ? 0 : -ENOENT;
>> + pr_debug("digest cache get %s, ret: %d\n", path_str, ret);
>> + path_put(&path);
>> + break;
>> + case DIGEST_CACHE_LOOKUP:
>> + 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)
>> + 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;
>> + }
>> + ret = 0;
>> + pr_debug("digest cache put, ret: %d\n", ret);
>> + break;
>> + case DIGEST_CACHE_ENABLE_VERIF:
>> + case DIGEST_CACHE_DISABLE_VERIF:
>> + 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 const struct file_operations digest_cache_notify_inodes_ops = {
>> + .open = generic_file_open,
>> + .write = write_notify_inodes,
>> + .read = read_notify_inodes,
>> + .llseek = generic_file_llseek,
>> +};
>> +
>> +static int __kprobes kernel_post_read_file_hook(struct kprobe *p,
>> + struct pt_regs *regs)
>> +{
>> +#ifdef CONFIG_HAVE_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;
>> +
>> + 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;
>> + }
>> +
>> + notify_inodes = securityfs_create_file("digest_cache_notify_inodes",
>> + 0660, NULL, NULL,
>> + &digest_cache_notify_inodes_ops);
>> + if (IS_ERR(notify_inodes)) {
>> + ret = PTR_ERR(notify_inodes);
>> + goto out_test;
>> + }
>> +
>> + ret = digest_cache_register_notifier(&digest_cache_notifier);
>> + if (ret < 0)
>> + goto out_notify_inodes;
>> +
>> + return 0;
>> +
>> +out_notify_inodes:
>> + securityfs_remove(notify_inodes);
>> +out_test:
>> + securityfs_remove(test);
>> +out_kprobe:
>> + unregister_kprobe(&kp);
>> + return ret;
>> +}
>> +
>> +static void __exit digest_cache_test_fini(void)
>> +{
>> + if (digest_cache)
>> + digest_cache_put(digest_cache);
>> +
>> + digest_cache_unregister_notifier(&digest_cache_notifier);
>> + securityfs_remove(notify_inodes);
>> + securityfs_remove(test);
>> + 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");
>
>
> BR, Jarkko