new file mode 100644
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2017-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu@huawei.com>
+ *
+ * Export definitions of the tlv digest list.
+ */
+
+#ifndef _UAPI_LINUX_TLV_DIGEST_LIST_H
+#define _UAPI_LINUX_TLV_DIGEST_LIST_H
+
+#include <linux/types.h>
+
+#define FOR_EACH_DIGEST_LIST_FIELD(DIGEST_LIST_FIELD) \
+ DIGEST_LIST_FIELD(DIGEST_LIST_ALGO) \
+ DIGEST_LIST_FIELD(DIGEST_LIST_NUM_ENTRIES) \
+ DIGEST_LIST_FIELD(DIGEST_LIST_ENTRY) \
+ DIGEST_LIST_FIELD(DIGEST_LIST_FIELD__LAST)
+
+#define FOR_EACH_DIGEST_LIST_ENTRY_FIELD(DIGEST_LIST_ENTRY_FIELD) \
+ DIGEST_LIST_ENTRY_FIELD(DIGEST_LIST_ENTRY_DIGEST) \
+ DIGEST_LIST_ENTRY_FIELD(DIGEST_LIST_ENTRY_PATH) \
+ DIGEST_LIST_ENTRY_FIELD(DIGEST_LIST_ENTRY_FIELD__LAST)
+
+#define GENERATE_ENUM(ENUM) ENUM,
+#define GENERATE_STRING(STRING) #STRING,
+
+/**
+ * enum digest_list_fields - Digest list fields
+ *
+ * Enumerates the digest list fields.
+ */
+enum digest_list_fields {
+ FOR_EACH_DIGEST_LIST_FIELD(GENERATE_ENUM)
+};
+
+/**
+ * enum digest_list_entry_fields - DIGEST_LIST_ENTRY fields
+ *
+ * Enumerates the DIGEST_LIST_ENTRY fields.
+ */
+enum digest_list_entry_fields {
+ FOR_EACH_DIGEST_LIST_ENTRY_FIELD(GENERATE_ENUM)
+};
+
+#endif /* _UAPI_LINUX_TLV_DIGEST_LIST_H */
@@ -33,3 +33,11 @@ config DIGEST_CACHE_HTABLE_DEPTH
A smaller number will increase the amount of hash table slots, and
make the search faster. A bigger number will decrease the number of
hash table slots, but make the search slower.
+
+config DIGEST_CACHE_TLV_PARSER
+ tristate "TLV digest list parser"
+ depends on INTEGRITY_DIGEST_CACHE
+ select TLV_PARSER
+ help
+ Add support for parsing TLV-formatted (Type Length Value)
+ digest list.
@@ -3,6 +3,7 @@
# Makefile for building the Integrity Digest Cache.
obj-$(CONFIG_INTEGRITY_DIGEST_CACHE) += digest_cache.o
+obj-$(CONFIG_DIGEST_CACHE_TLV_PARSER) += parsers/tlv.o
digest_cache-y := main.o secfs.o htable.o parsers.o
new file mode 100644
@@ -0,0 +1,341 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu@huawei.com>
+ *
+ * Parse a tlv digest list.
+ */
+
+#define pr_fmt(fmt) "digest_cache TLV PARSER: "fmt
+#include <linux/module.h>
+#include <linux/tlv_parser.h>
+#include <linux/digest_cache.h>
+#include <uapi/linux/tlv_digest_list.h>
+
+#define kenter(FMT, ...) \
+ pr_debug("==> %s(" FMT ")\n", __func__, ##__VA_ARGS__)
+#define kleave(FMT, ...) \
+ pr_debug("<== %s()" FMT "\n", __func__, ##__VA_ARGS__)
+
+static const char *digest_list_fields_str[] = {
+ FOR_EACH_DIGEST_LIST_FIELD(GENERATE_STRING)
+};
+
+static const char *digest_list_entry_fields_str[] = {
+ FOR_EACH_DIGEST_LIST_ENTRY_FIELD(GENERATE_STRING)
+};
+
+struct tlv_callback_data {
+ struct digest_cache *digest_cache;
+ enum hash_algo algo;
+};
+
+/**
+ * parse_digest_list_entry_digest - Parse DIGEST_LIST_ENTRY_DIGEST field
+ * @tlv_data: Callback data
+ * @field: Field identifier
+ * @field_data: Field data
+ * @field_data_len: Length of @field_data
+ *
+ * This function parses the DIGEST_LIST_ENTRY_DIGEST field (file digest).
+ *
+ * Return: Zero on success, a POSIX error code otherwise.
+ */
+static int parse_digest_list_entry_digest(struct tlv_callback_data *tlv_data,
+ enum digest_list_entry_fields field,
+ const __u8 *field_data,
+ __u32 field_data_len)
+{
+ int ret;
+
+ kenter(",%u,%u", field, field_data_len);
+
+ if (tlv_data->algo == HASH_ALGO__LAST) {
+ pr_debug("Digest algo not set\n");
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ if (field_data_len != hash_digest_size[tlv_data->algo]) {
+ pr_debug("Unexpected data length %u, expected %d\n",
+ field_data_len, hash_digest_size[tlv_data->algo]);
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ ret = digest_cache_htable_add(tlv_data->digest_cache,
+ (__u8 *)field_data, tlv_data->algo);
+out:
+ kleave(" = %d", ret);
+ return ret;
+}
+
+/**
+ * parse_digest_list_entry_path - Parse DIGEST_LIST_ENTRY_PATH field
+ * @tlv_data: Callback data
+ * @field: Field identifier
+ * @field_data: Field data
+ * @field_data_len: Length of @field_data
+ *
+ * This function handles the DIGEST_LIST_ENTRY_PATH field (file path). It
+ * currently does not parse the data.
+ *
+ * Return: Zero.
+ */
+static int parse_digest_list_entry_path(struct tlv_callback_data *tlv_data,
+ enum digest_list_entry_fields field,
+ const __u8 *field_data,
+ __u32 field_data_len)
+{
+ kenter(",%u,%u", field, field_data_len);
+
+ kleave(" = 0");
+ return 0;
+}
+
+/**
+ * digest_list_entry_callback - DIGEST_LIST_ENTRY callback
+ * @callback_data: Callback data
+ * @field: Field identifier
+ * @field_data: Field data
+ * @field_data_len: Length of @field_data
+ *
+ * This callback handles the fields of DIGEST_LIST_ENTRY (nested) data, and
+ * calls the appropriate parser.
+ *
+ * Return: Zero on success, a POSIX error code otherwise.
+ */
+static int digest_list_entry_callback(void *callback_data, __u16 field,
+ const __u8 *field_data,
+ __u32 field_data_len)
+{
+ struct tlv_callback_data *tlv_data;
+ int ret;
+
+ tlv_data = (struct tlv_callback_data *)callback_data;
+
+ switch (field) {
+ case DIGEST_LIST_ENTRY_DIGEST:
+ ret = parse_digest_list_entry_digest(tlv_data, field,
+ field_data,
+ field_data_len);
+ break;
+ case DIGEST_LIST_ENTRY_PATH:
+ ret = parse_digest_list_entry_path(tlv_data, field, field_data,
+ field_data_len);
+ break;
+ default:
+ pr_debug("Unhandled field %s\n",
+ digest_list_entry_fields_str[field]);
+ /* Just ignore non-relevant fields. */
+ ret = 0;
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * parse_digest_list_algo - Parse DIGEST_LIST_ALGO field
+ * @tlv_data: Callback data
+ * @field: Field identifier
+ * @field_data: Field data
+ * @field_data_len: Length of @field_data
+ *
+ * This function parses the DIGEST_LIST_ALGO field (digest algorithm).
+ *
+ * Return: Zero on success, a POSIX error code otherwise.
+ */
+static int parse_digest_list_algo(struct tlv_callback_data *tlv_data,
+ enum digest_list_fields field,
+ const __u8 *field_data, __u32 field_data_len)
+{
+ __u16 algo;
+ int ret = 0;
+
+ kenter(",%u,%u", field, field_data_len);
+
+ if (field_data_len != sizeof(__u16)) {
+ pr_debug("Unexpected data length %u, expected %zu\n",
+ field_data_len, sizeof(__u16));
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ algo = __be16_to_cpu(*(__u16 *)field_data);
+
+ if (algo >= HASH_ALGO__LAST) {
+ pr_debug("Unexpected digest algo %u\n", algo);
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ tlv_data->algo = algo;
+
+ pr_debug("Digest algo: %s\n", hash_algo_name[algo]);
+out:
+ kleave(" = %d", ret);
+ return ret;
+}
+
+/**
+ * parse_digest_list_num_entries - Parse DIGEST_LIST_NUM_ENTRIES field
+ * @tlv_data: Callback data
+ * @field: Field identifier
+ * @field_data: Field data
+ * @field_data_len: Length of @field_data
+ *
+ * This function parses the DIGEST_LIST_NUM_ENTRIES field (digest list entries).
+ * This field must appear after DIGEST_LIST_ALGO.
+ *
+ * Return: Zero on success, a POSIX error code otherwise.
+ */
+static int parse_digest_list_num_entries(struct tlv_callback_data *tlv_data,
+ enum digest_list_fields field,
+ const __u8 *field_data,
+ __u32 field_data_len)
+{
+ __u32 num_entries;
+ int ret;
+
+ kenter(",%u,%u", field, field_data_len);
+
+ if (field_data_len != sizeof(__u32)) {
+ pr_debug("Unexpected data length %u, expected %zu\n",
+ field_data_len, sizeof(__u32));
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ if (tlv_data->algo == HASH_ALGO__LAST) {
+ pr_debug("Digest algo not yet initialized\n");
+ ret = -EBADMSG;
+ goto out;
+ }
+
+ num_entries = __be32_to_cpu(*(__u32 *)field_data);
+
+ ret = digest_cache_htable_init(tlv_data->digest_cache, num_entries,
+ tlv_data->algo);
+out:
+ kleave(" = %d", ret);
+ return ret;
+}
+
+/**
+ * parse_digest_list_entry - Parse DIGEST_LIST_ENTRY field
+ * @tlv_data: Callback data
+ * @field: Field identifier
+ * @field_data: Field data
+ * @field_data_len: Length of @field_data
+ *
+ * This function parses the DIGEST_LIST_ENTRY field.
+ *
+ * Return: Zero on success, a POSIX error code otherwise.
+ */
+static int parse_digest_list_entry(struct tlv_callback_data *tlv_data,
+ enum digest_list_fields field,
+ const __u8 *field_data, __u32 field_data_len)
+{
+ int ret;
+
+ kenter(",%u,%u", field, field_data_len);
+
+ ret = tlv_parse(digest_list_entry_callback, tlv_data, field_data,
+ field_data_len, digest_list_entry_fields_str,
+ DIGEST_LIST_ENTRY_FIELD__LAST);
+
+ kleave(" = %d", ret);
+ return ret;
+}
+
+/**
+ * digest_list_callback - Digest list callback
+ * @callback_data: Callback data
+ * @field: Field identifier
+ * @field_data: Field data
+ * @field_data_len: Length of @field_data
+ *
+ * This callback handles the digest list fields, and calls the appropriate
+ * parser.
+ *
+ * Return: Zero on success, a POSIX error code otherwise.
+ */
+static int digest_list_callback(void *callback_data, __u16 field,
+ const __u8 *field_data, __u32 field_data_len)
+{
+ struct tlv_callback_data *tlv_data;
+ int ret;
+
+ tlv_data = (struct tlv_callback_data *)callback_data;
+
+ switch (field) {
+ case DIGEST_LIST_ALGO:
+ ret = parse_digest_list_algo(tlv_data, field, field_data,
+ field_data_len);
+ break;
+ case DIGEST_LIST_NUM_ENTRIES:
+ ret = parse_digest_list_num_entries(tlv_data, field, field_data,
+ field_data_len);
+ break;
+ case DIGEST_LIST_ENTRY:
+ ret = parse_digest_list_entry(tlv_data, field, field_data,
+ field_data_len);
+ break;
+ default:
+ pr_debug("Unhandled field %s\n",
+ digest_list_fields_str[field]);
+ /* Just ignore non-relevant fields. */
+ ret = 0;
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * digest_list_parse_tlv - Parse a tlv digest list
+ * @digest_cache: Digest cache
+ * @data: Data to parse
+ * @data_len: Length of @data
+ *
+ * This function parses a tlv digest list.
+ *
+ * Return: Zero on success, a POSIX error code otherwise.
+ */
+static int digest_list_parse_tlv(struct digest_cache *digest_cache,
+ const __u8 *data, size_t data_len)
+{
+ struct tlv_callback_data tlv_data = {
+ .digest_cache = digest_cache,
+ .algo = HASH_ALGO__LAST,
+ };
+
+ return tlv_parse(digest_list_callback, &tlv_data, data, data_len,
+ digest_list_fields_str, DIGEST_LIST_FIELD__LAST);
+}
+
+static struct parser tlv_parser = {
+ .name = "tlv",
+ .owner = THIS_MODULE,
+ .func = digest_list_parse_tlv,
+};
+
+static int __init tlv_parser_init(void)
+{
+ return digest_cache_register_parser(&tlv_parser);
+}
+
+static void __exit tlv_parser_exit(void)
+{
+ digest_cache_unregister_parser(&tlv_parser);
+}
+
+module_init(tlv_parser_init);
+module_exit(tlv_parser_exit);
+
+MODULE_AUTHOR("Roberto Sassu");
+MODULE_DESCRIPTION("TLV digest list parser");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1.0.0");