@@ -22148,6 +22148,14 @@ W: http://sourceforge.net/projects/tlan/
F: Documentation/networking/device_drivers/ethernet/ti/tlan.rst
F: drivers/net/ethernet/ti/tlan.*
+TLV PARSER
+M: Roberto Sassu <roberto.sassu@huawei.com>
+L: linux-kernel@vger.kernel.org
+S: Maintained
+F: include/linux/tlv_parser.h
+F: include/uapi/linux/tlv_parser.h
+F: lib/tlv_parser.*
+
TMIO/SDHI MMC DRIVER
M: Wolfram Sang <wsa+renesas@sang-engineering.com>
L: linux-mmc@vger.kernel.org
new file mode 100644
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu@huawei.com>
+ *
+ * Header file of TLV parser.
+ */
+
+#ifndef _LINUX_TLV_PARSER_H
+#define _LINUX_TLV_PARSER_H
+
+#include <uapi/linux/tlv_parser.h>
+
+typedef int (*parse_callback)(void *, __u64, const __u8 *, __u64);
+
+int tlv_parse_hdr(const __u8 **data, size_t *data_len, __u64 *parsed_data_type,
+ __u64 *parsed_num_entries, __u64 *parsed_total_len,
+ const char **data_types, __u64 num_data_types);
+int tlv_parse_data(parse_callback callback, void *callback_data,
+ __u64 num_entries, const __u8 *data, size_t data_len,
+ const char **fields, __u64 num_fields);
+int tlv_parse(__u64 expected_data_type, parse_callback callback,
+ void *callback_data, const __u8 *data, size_t data_len,
+ const char **data_types, __u64 num_data_types,
+ const char **fields, __u64 num_fields);
+
+#endif /* _LINUX_TLV_PARSER_H */
new file mode 100644
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu@huawei.com>
+ *
+ * Implement the user space interface for the TLV parser.
+ */
+
+#ifndef _UAPI_LINUX_TLV_PARSER_H
+#define _UAPI_LINUX_TLV_PARSER_H
+
+#include <linux/types.h>
+
+/*
+ * TLV format:
+ *
+ * +-----------------+------------------+-----------------+
+ * | data type (u64) | num fields (u64) | total len (u64) | # header
+ * +--------------+--+---------+--------+---------+-------+
+ * | field1 (u64) | len1 (u64) | value1 (u8 len1) |
+ * +--------------+------------+------------------+
+ * | ... | ... | ... | # data
+ * +--------------+------------+------------------+
+ * | fieldN (u64) | lenN (u64) | valueN (u8 lenN) |
+ * +--------------+------------+------------------+
+ */
+
+/**
+ * struct tlv_hdr - Header of TLV format
+ * @data_type: Type of data to parse
+ * @num_entries: Number of data entries provided
+ * @_reserved: Reserved for future use (must be equal to zero)
+ * @total_len: Total length of the data blob, excluding the header
+ *
+ * This structure represents the header of the TLV data format.
+ */
+struct tlv_hdr {
+ __u64 data_type;
+ __u64 num_entries;
+ __u64 _reserved;
+ __u64 total_len;
+} __attribute__((packed));
+
+/**
+ * struct tlv_data_entry - Data entry of TLV format
+ * @field: Data field identifier
+ * @length: Data length
+ * @data: Data
+ *
+ * This structure represents a TLV entry of the data part of TLV data format.
+ */
+struct tlv_data_entry {
+ __u64 field;
+ __u64 length;
+ __u8 data[];
+} __attribute__((packed));
+
+#endif /* _UAPI_LINUX_TLV_PARSER_H */
@@ -785,3 +785,6 @@ config POLYNOMIAL
config FIRMWARE_TABLE
bool
+
+config TLV_PARSER
+ bool
@@ -444,3 +444,6 @@ $(obj)/$(TEST_FORTIFY_LOG): $(addprefix $(obj)/, $(TEST_FORTIFY_LOGS)) FORCE
ifeq ($(CONFIG_FORTIFY_SOURCE),y)
$(obj)/string.o: $(obj)/$(TEST_FORTIFY_LOG)
endif
+
+obj-$(CONFIG_TLV_PARSER) += tlv_parser.o
+CFLAGS_tlv_parser.o += -I lib
new file mode 100644
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2023-2024 Huawei Technologies Duesseldorf GmbH
+ *
+ * Author: Roberto Sassu <roberto.sassu@huawei.com>
+ *
+ * Implement the TLV parser.
+ */
+
+#define pr_fmt(fmt) "TLV PARSER: "fmt
+#include <tlv_parser.h>
+
+/**
+ * tlv_parse_hdr - Parse TLV header
+ * @data: Data to parse (updated)
+ * @data_len: Length of @data (updated)
+ * @parsed_data_type: Parsed data type (updated)
+ * @parsed_num_entries: Parsed number of data entries (updated)
+ * @parsed_total_len: Parsed length of TLV data, excluding the header (updated)
+ * @data_types: Array of data type strings
+ * @num_data_types: Number of elements of @data_types
+ *
+ * Parse the header of the TLV data format, move the data pointer to the TLV
+ * data part, decrease the data length by the length of the header, and provide
+ * the data type, number of entries and the total data length extracted from the
+ * header.
+ *
+ * Return: Zero on success, a negative value on error.
+ */
+int tlv_parse_hdr(const __u8 **data, size_t *data_len, __u64 *parsed_data_type,
+ __u64 *parsed_num_entries, __u64 *parsed_total_len,
+ const char **data_types, __u64 num_data_types)
+{
+ struct tlv_hdr *hdr;
+
+ if (*data_len < sizeof(*hdr)) {
+ pr_debug("Data blob too short, %lu bytes, expected %lu\n",
+ *data_len, sizeof(*hdr));
+ return -EBADMSG;
+ }
+
+ hdr = (struct tlv_hdr *)*data;
+
+ *data += sizeof(*hdr);
+ *data_len -= sizeof(*hdr);
+
+ *parsed_data_type = __be64_to_cpu(hdr->data_type);
+ if (*parsed_data_type >= num_data_types) {
+ pr_debug("Invalid data type %llu, max: %llu\n",
+ *parsed_data_type, num_data_types - 1);
+ return -EBADMSG;
+ }
+
+ *parsed_num_entries = __be64_to_cpu(hdr->num_entries);
+
+ if (hdr->_reserved != 0) {
+ pr_debug("_reserved must be zero\n");
+ return -EBADMSG;
+ }
+
+ *parsed_total_len = __be64_to_cpu(hdr->total_len);
+ if (*parsed_total_len > *data_len) {
+ pr_debug("Invalid total length %llu, expected: %lu\n",
+ *parsed_total_len, *data_len);
+ return -EBADMSG;
+ }
+
+ pr_debug("Header: type: %s, num entries: %llu, total len: %lld\n",
+ data_types[*parsed_data_type], *parsed_num_entries,
+ *parsed_total_len);
+
+ return 0;
+}
+
+/**
+ * tlv_parse_data - Parse TLV data
+ * @callback: Callback function to call to parse the entries
+ * @callback_data: Opaque data to supply to the callback function
+ * @num_entries: Number of data entries to parse
+ * @data: Data to parse
+ * @data_len: Length of @data
+ * @fields: Array of field strings
+ * @num_fields: Number of elements of @fields
+ *
+ * Parse the data part of the TLV data format and call the supplied callback
+ * function for each data entry, passing also the opaque data pointer.
+ *
+ * The callback function decides how to process data depending on the field.
+ *
+ * Return: Zero on success, a negative value on error.
+ */
+int tlv_parse_data(parse_callback callback, void *callback_data,
+ __u64 num_entries, const __u8 *data, size_t data_len,
+ const char **fields, __u64 num_fields)
+{
+ const __u8 *data_ptr = data;
+ struct tlv_data_entry *entry;
+ __u64 parsed_field, len, i, max_num_entries;
+ int ret;
+
+ max_num_entries = data_len / sizeof(*entry);
+
+ /* Finite termination on num_entries. */
+ if (num_entries > max_num_entries)
+ return -EBADMSG;
+
+ for (i = 0; i < num_entries; i++) {
+ if (data_len < sizeof(*entry))
+ return -EBADMSG;
+
+ entry = (struct tlv_data_entry *)data_ptr;
+ data_ptr += sizeof(*entry);
+ data_len -= sizeof(*entry);
+
+ parsed_field = __be64_to_cpu(entry->field);
+ if (parsed_field >= num_fields) {
+ pr_debug("Invalid field %llu, max: %llu\n",
+ parsed_field, num_fields - 1);
+ return -EBADMSG;
+ }
+
+ len = __be64_to_cpu(entry->length);
+
+ if (data_len < len)
+ return -EBADMSG;
+
+ pr_debug("Data: field: %s, len: %llu\n", fields[parsed_field],
+ len);
+
+ if (!len)
+ continue;
+
+ ret = callback(callback_data, parsed_field, data_ptr, len);
+ if (ret < 0) {
+ pr_debug("Parsing of field %s failed, ret: %d\n",
+ fields[parsed_field], ret);
+ return ret;
+ }
+
+ data_ptr += len;
+ data_len -= len;
+ }
+
+ if (data_len) {
+ pr_debug("Excess data: %lu bytes\n", data_len);
+ return -EBADMSG;
+ }
+
+ return 0;
+}
+
+/**
+ * tlv_parse - Parse data in TLV format
+ * @expected_data_type: Desired data type
+ * @callback: Callback function to call to parse the data entries
+ * @callback_data: Opaque data to supply to the callback function
+ * @data: Data to parse
+ * @data_len: Length of @data
+ * @data_types: Array of data type strings
+ * @num_data_types: Number of elements of @data_types
+ * @fields: Array of field strings
+ * @num_fields: Number of elements of @fields
+ *
+ * Parse data in TLV format and call tlv_parse_data() each time the header has
+ * the same data type as the expected one.
+ *
+ * Return: Zero on success, a negative value on error.
+ */
+int tlv_parse(__u64 expected_data_type, parse_callback callback,
+ void *callback_data, const __u8 *data, size_t data_len,
+ const char **data_types, __u64 num_data_types,
+ const char **fields, __u64 num_fields)
+{
+ __u64 parsed_data_type, parsed_num_entries, parsed_total_len;
+ const __u8 *data_ptr = data;
+ int ret = 0;
+
+ pr_debug("Start parsing data blob, size: %lu, expected data type: %s\n",
+ data_len, data_types[expected_data_type]);
+
+ while (data_len) {
+ ret = tlv_parse_hdr(&data_ptr, &data_len, &parsed_data_type,
+ &parsed_num_entries, &parsed_total_len,
+ data_types, num_data_types);
+ if (ret < 0)
+ goto out;
+
+ /* Skip data with a different data type than expected. */
+ if (parsed_data_type != expected_data_type) {
+ /*
+ * tlv_parse_hdr() already checked that
+ * parsed_total_len <= data_len.
+ */
+ data_ptr += parsed_total_len;
+ data_len -= parsed_total_len;
+ continue;
+ }
+
+ pr_debug("Found data type %s at offset %ld\n",
+ data_types[parsed_data_type], data_ptr - data);
+
+ ret = tlv_parse_data(callback, callback_data,
+ parsed_num_entries, data_ptr,
+ parsed_total_len, fields, num_fields);
+ if (ret < 0)
+ goto out;
+
+ data_ptr += parsed_total_len;
+ data_len -= parsed_total_len;
+ }
+out:
+ pr_debug("End of parsing data blob, ret: %d\n", ret);
+ return ret;
+}
new file mode 100644
@@ -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 file of TLV parser.
+ */
+
+#ifndef _LIB_TLV_PARSER_H
+#define _LIB_TLV_PARSER_H
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/tlv_parser.h>
+
+#endif /* _LIB_TLV_PARSER_H */