1 files changed, 478 insertions, 0 deletions
diff --git a/drivers/partition/partition.c b/drivers/partition/partition.c
new file mode 100644
index 0000000..c60820d
--- /dev/null
+++ b/drivers/partition/partition.c
@@ -0,0 +1,478 @@
+/*
+ * Copyright (c) 2016-2023, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <common/debug.h>
+#include <common/tf_crc32.h>
+#include <drivers/io/io_storage.h>
+#include <drivers/partition/efi.h>
+#include <drivers/partition/partition.h>
+#include <drivers/partition/gpt.h>
+#include <drivers/partition/mbr.h>
+#include <plat/common/platform.h>
+
+static uint8_t mbr_sector[PLAT_PARTITION_BLOCK_SIZE];
+static partition_entry_list_t list;
+
+#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
+static void dump_entries(int num)
+{
+	char name[EFI_NAMELEN];
+	int i, j, len;
+
+	VERBOSE("Partition table with %d entries:\n", num);
+	for (i = 0; i < num; i++) {
+		len = snprintf(name, EFI_NAMELEN, "%s", list.list[i].name);
+		for (j = 0; j < EFI_NAMELEN - len - 1; j++) {
+			name[len + j] = ' ';
+		}
+		name[EFI_NAMELEN - 1] = '\0';
+		VERBOSE("%d: %s %" PRIx64 "-%" PRIx64 "\n", i + 1, name, list.list[i].start,
+			list.list[i].start + list.list[i].length - 4);
+	}
+}
+#else
+#define dump_entries(num)	((void)num)
+#endif
+
+/*
+ * Load the first sector that carries MBR header.
+ * The MBR boot signature should be always valid whether it's MBR or GPT.
+ */
+static int load_mbr_header(uintptr_t image_handle, mbr_entry_t *mbr_entry)
+{
+	size_t bytes_read;
+	int result;
+	mbr_entry_t *tmp;
+
+	assert(mbr_entry != NULL);
+	/* MBR partition table is in LBA0. */
+	result = io_seek(image_handle, IO_SEEK_SET, MBR_OFFSET);
+	if (result != 0) {
+		VERBOSE("Failed to seek (%i)\n", result);
+		return result;
+	}
+	result = io_read(image_handle, (uintptr_t)&mbr_sector,
+			 PLAT_PARTITION_BLOCK_SIZE, &bytes_read);
+	if ((result != 0) || (bytes_read != PLAT_PARTITION_BLOCK_SIZE)) {
+		VERBOSE("Failed to read data (%i)\n", result);
+		return result;
+	}
+
+	/* Check MBR boot signature. */
+	if ((mbr_sector[LEGACY_PARTITION_BLOCK_SIZE - 2] != MBR_SIGNATURE_FIRST) ||
+	    (mbr_sector[LEGACY_PARTITION_BLOCK_SIZE - 1] != MBR_SIGNATURE_SECOND)) {
+		VERBOSE("MBR boot signature failure\n");
+		return -ENOENT;
+	}
+
+	tmp = (mbr_entry_t *)(&mbr_sector[MBR_PRIMARY_ENTRY_OFFSET]);
+
+	if (tmp->first_lba != 1) {
+		VERBOSE("MBR header may have an invalid first LBA\n");
+		return -EINVAL;
+	}
+
+	if ((tmp->sector_nums == 0) || (tmp->sector_nums == UINT32_MAX)) {
+		VERBOSE("MBR header entry has an invalid number of sectors\n");
+		return -EINVAL;
+	}
+
+	memcpy(mbr_entry, tmp, sizeof(mbr_entry_t));
+	return 0;
+}
+
+/*
+ * Load GPT header and check the GPT signature and header CRC.
+ * If partition numbers could be found, check & update it.
+ */
+static int load_gpt_header(uintptr_t image_handle, size_t header_offset,
+			   unsigned long long *part_lba)
+{
+	gpt_header_t header;
+	size_t bytes_read;
+	int result;
+	uint32_t header_crc, calc_crc;
+
+	result = io_seek(image_handle, IO_SEEK_SET, header_offset);
+	if (result != 0) {
+		VERBOSE("Failed to seek into the GPT image at offset (%zu)\n",
+			header_offset);
+		return result;
+	}
+	result = io_read(image_handle, (uintptr_t)&header,
+			 sizeof(gpt_header_t), &bytes_read);
+	if ((result != 0) || (sizeof(gpt_header_t) != bytes_read)) {
+		VERBOSE("GPT header read error(%i) or read mismatch occurred,"
+			"expected(%zu) and actual(%zu)\n", result,
+			sizeof(gpt_header_t), bytes_read);
+		return result;
+	}
+	if (memcmp(header.signature, GPT_SIGNATURE,
+			   sizeof(header.signature)) != 0) {
+		VERBOSE("GPT header signature failure\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * UEFI Spec 2.8 March 2019 Page 119: HeaderCRC32 value is
+	 * computed by setting this field to 0, and computing the
+	 * 32-bit CRC for HeaderSize bytes.
+	 */
+	header_crc = header.header_crc;
+	header.header_crc = 0U;
+
+	calc_crc = tf_crc32(0U, (uint8_t *)&header, sizeof(gpt_header_t));
+	if (header_crc != calc_crc) {
+		ERROR("Invalid GPT Header CRC: Expected 0x%x but got 0x%x.\n",
+		      header_crc, calc_crc);
+		return -EINVAL;
+	}
+
+	header.header_crc = header_crc;
+
+	/* partition numbers can't exceed PLAT_PARTITION_MAX_ENTRIES */
+	list.entry_count = header.list_num;
+	if (list.entry_count > PLAT_PARTITION_MAX_ENTRIES) {
+		list.entry_count = PLAT_PARTITION_MAX_ENTRIES;
+	}
+
+	*part_lba = header.part_lba;
+	return 0;
+}
+
+/*
+ * Load a single MBR entry based on details from MBR header.
+ */
+static int load_mbr_entry(uintptr_t image_handle, mbr_entry_t *mbr_entry,
+			  int part_number)
+{
+	size_t bytes_read;
+	uintptr_t offset;
+	int result;
+
+	assert(mbr_entry != NULL);
+	/* MBR partition table is in LBA0. */
+	result = io_seek(image_handle, IO_SEEK_SET, MBR_OFFSET);
+	if (result != 0) {
+		VERBOSE("Failed to seek (%i)\n", result);
+		return result;
+	}
+	result = io_read(image_handle, (uintptr_t)&mbr_sector,
+			 PLAT_PARTITION_BLOCK_SIZE, &bytes_read);
+	if (result != 0) {
+		VERBOSE("Failed to read data (%i)\n", result);
+		return result;
+	}
+
+	/* Check MBR boot signature. */
+	if ((mbr_sector[LEGACY_PARTITION_BLOCK_SIZE - 2] != MBR_SIGNATURE_FIRST) ||
+	    (mbr_sector[LEGACY_PARTITION_BLOCK_SIZE - 1] != MBR_SIGNATURE_SECOND)) {
+		VERBOSE("MBR Entry boot signature failure\n");
+		return -ENOENT;
+	}
+	offset = (uintptr_t)&mbr_sector +
+		MBR_PRIMARY_ENTRY_OFFSET +
+		MBR_PRIMARY_ENTRY_SIZE * part_number;
+	memcpy(mbr_entry, (void *)offset, sizeof(mbr_entry_t));
+
+	return 0;
+}
+
+/*
+ * Load MBR entries based on max number of partition entries.
+ */
+static int load_mbr_entries(uintptr_t image_handle)
+{
+	mbr_entry_t mbr_entry;
+	int i;
+
+	list.entry_count = MBR_PRIMARY_ENTRY_NUMBER;
+
+	for (i = 0; i < list.entry_count; i++) {
+		load_mbr_entry(image_handle, &mbr_entry, i);
+		list.list[i].start = mbr_entry.first_lba * 512;
+		list.list[i].length = mbr_entry.sector_nums * 512;
+		list.list[i].name[0] = mbr_entry.type;
+	}
+
+	return 0;
+}
+
+/*
+ * Try to read and load a single GPT entry.
+ */
+static int load_gpt_entry(uintptr_t image_handle, gpt_entry_t *entry)
+{
+	size_t bytes_read = 0U;
+	int result;
+
+	assert(entry != NULL);
+	result = io_read(image_handle, (uintptr_t)entry, sizeof(gpt_entry_t),
+			&bytes_read);
+	if ((result != 0) || (sizeof(gpt_entry_t) != bytes_read)) {
+		VERBOSE("GPT Entry read error(%i) or read mismatch occurred,"
+			"expected(%zu) and actual(%zu)\n", result,
+			sizeof(gpt_entry_t), bytes_read);
+		return -EINVAL;
+	}
+
+	return result;
+}
+
+/*
+ * Retrieve each entry in the partition table, parse the data from each
+ * entry and store them in the list of partition table entries.
+ */
+static int load_partition_gpt(uintptr_t image_handle,
+			      unsigned long long part_lba)
+{
+	const signed long long gpt_entry_offset = LBA(part_lba);
+	gpt_entry_t entry;
+	int result, i;
+
+	result = io_seek(image_handle, IO_SEEK_SET, gpt_entry_offset);
+	if (result != 0) {
+		VERBOSE("Failed to seek (%i), Failed loading GPT partition"
+			"table entries\n", result);
+		return result;
+	}
+
+	for (i = 0; i < list.entry_count; i++) {
+		result = load_gpt_entry(image_handle, &entry);
+		if (result != 0) {
+			VERBOSE("Failed to load gpt entry data(%i) error is (%i)\n",
+				i, result);
+			return result;
+		}
+
+		result = parse_gpt_entry(&entry, &list.list[i]);
+		if (result != 0) {
+			break;
+		}
+	}
+	if (i == 0) {
+		VERBOSE("No Valid GPT Entries found\n");
+		return -EINVAL;
+	}
+	/*
+	 * Only records the valid partition number that is loaded from
+	 * partition table.
+	 */
+	list.entry_count = i;
+	dump_entries(list.entry_count);
+
+	return 0;
+}
+
+/*
+ * Try retrieving and parsing the backup-GPT header and backup GPT entries.
+ * Last 33 blocks contains the backup-GPT entries and header.
+ */
+static int load_backup_gpt(unsigned int image_id, unsigned int sector_nums)
+{
+	int result;
+	unsigned long long part_lba = 0;
+	size_t gpt_header_offset;
+	uintptr_t dev_handle, image_spec, image_handle;
+	io_block_spec_t *block_spec;
+	int part_num_entries;
+
+	result = plat_get_image_source(image_id, &dev_handle, &image_spec);
+	if (result != 0) {
+		VERBOSE("Failed to obtain reference to image id=%u (%i)\n",
+			image_id, result);
+		return result;
+	}
+
+	block_spec = (io_block_spec_t *)image_spec;
+	/*
+	 * We need to read 32 blocks of GPT entries and one block of GPT header
+	 * try mapping only last 33 last blocks from the image to read the
+	 * Backup-GPT header and its entries.
+	 */
+	part_num_entries = (PLAT_PARTITION_MAX_ENTRIES / 4);
+	/* Move the offset base to LBA-33 */
+	block_spec->offset += LBA(sector_nums - part_num_entries);
+	/*
+	 * Set length as LBA-33, 32 blocks of backup-GPT entries and one
+	 * block of backup-GPT header.
+	 */
+	block_spec->length = LBA(part_num_entries + 1);
+
+	result = io_open(dev_handle, image_spec, &image_handle);
+	if (result != 0) {
+		VERBOSE("Failed to access image id (%i)\n", result);
+		return result;
+	}
+
+	INFO("Trying to retrieve back-up GPT header\n");
+	/* Last block is backup-GPT header, after the end of GPT entries */
+	gpt_header_offset = LBA(part_num_entries);
+	result = load_gpt_header(image_handle, gpt_header_offset, &part_lba);
+	if ((result != 0) || (part_lba == 0)) {
+		ERROR("Failed to retrieve Backup GPT header,"
+		      "Partition maybe corrupted\n");
+		goto out;
+	}
+
+	/*
+	 * Note we mapped last 33 blocks(LBA-33), first block here starts with
+	 * entries while last block was header.
+	 */
+	result = load_partition_gpt(image_handle, 0);
+
+out:
+	io_close(image_handle);
+	return result;
+}
+
+/*
+ * Load a GPT partition, Try retrieving and parsing the primary GPT header,
+ * if its corrupted try loading backup GPT header and then retrieve list
+ * of partition table entries found from the GPT.
+ */
+static int load_primary_gpt(uintptr_t image_handle, unsigned int first_lba)
+{
+	int result;
+	unsigned long long part_lba;
+	size_t gpt_header_offset;
+
+	/* Try to load Primary GPT header from LBA1 */
+	gpt_header_offset = LBA(first_lba);
+	result = load_gpt_header(image_handle, gpt_header_offset, &part_lba);
+	if ((result != 0) || (part_lba == 0)) {
+		VERBOSE("Failed to retrieve Primary GPT header,"
+			"trying to retrieve back-up GPT header\n");
+		return result;
+	}
+
+	return load_partition_gpt(image_handle, part_lba);
+}
+
+/*
+ * Load the partition table info based on the image id provided.
+ */
+int load_partition_table(unsigned int image_id)
+{
+	uintptr_t dev_handle, image_handle, image_spec = 0;
+	mbr_entry_t mbr_entry;
+	int result;
+
+	result = plat_get_image_source(image_id, &dev_handle, &image_spec);
+	if (result != 0) {
+		VERBOSE("Failed to obtain reference to image id=%u (%i)\n",
+			image_id, result);
+		return result;
+	}
+
+	result = io_open(dev_handle, image_spec, &image_handle);
+	if (result != 0) {
+		VERBOSE("Failed to access image id=%u (%i)\n", image_id, result);
+		return result;
+	}
+
+	result = load_mbr_header(image_handle, &mbr_entry);
+	if (result != 0) {
+		VERBOSE("Failed to access image id=%u (%i)\n", image_id, result);
+		goto out;
+	}
+	if (mbr_entry.type == PARTITION_TYPE_GPT) {
+		result = load_primary_gpt(image_handle, mbr_entry.first_lba);
+		if (result != 0) {
+			io_close(image_handle);
+			return load_backup_gpt(BKUP_GPT_IMAGE_ID,
+					       mbr_entry.sector_nums);
+		}
+	} else {
+		result = load_mbr_entries(image_handle);
+	}
+
+out:
+	io_close(image_handle);
+	return result;
+}
+
+/*
+ * Try retrieving a partition table entry based on the name of the partition.
+ */
+const partition_entry_t *get_partition_entry(const char *name)
+{
+	int i;
+
+	for (i = 0; i < list.entry_count; i++) {
+		if (strcmp(name, list.list[i].name) == 0) {
+			return &list.list[i];
+		}
+	}
+	return NULL;
+}
+
+/*
+ * Try retrieving a partition table entry based on the GUID.
+ */
+const partition_entry_t *get_partition_entry_by_type(const uuid_t *type_uuid)
+{
+	int i;
+
+	for (i = 0; i < list.entry_count; i++) {
+		if (guidcmp(type_uuid, &list.list[i].type_guid) == 0) {
+			return &list.list[i];
+		}
+	}
+
+	return NULL;
+}
+
+/*
+ * Try retrieving a partition table entry based on the UUID.
+ */
+const partition_entry_t *get_partition_entry_by_uuid(const uuid_t *part_uuid)
+{
+	int i;
+
+	for (i = 0; i < list.entry_count; i++) {
+		if (guidcmp(part_uuid, &list.list[i].part_guid) == 0) {
+			return &list.list[i];
+		}
+	}
+
+	return NULL;
+}
+
+/*
+ * Return entry to the list of partition table entries.
+ */
+const partition_entry_list_t *get_partition_entry_list(void)
+{
+	return &list;
+}
+
+/*
+ * Try loading partition table info for the given image ID.
+ */
+void partition_init(unsigned int image_id)
+{
+	int ret;
+
+	ret = load_partition_table(image_id);
+	if (ret != 0) {
+		ERROR("Failed to parse partition with image id = %u\n",
+		      image_id);
+	}
+}
+
+/*
+ * Load a GPT based image.
+ */
+int gpt_partition_init(void)
+{
+	return load_partition_table(GPT_IMAGE_ID);
+}