// SPDX-License-Identifier: LGPL-2.1-or-later
/*
 * libefiboot - library for the manipulation of EFI boot variables
 * Copyright 2012-2019 Red Hat, Inc.
 */

#include "fix_coverity.h"

#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdint.h>
#include <unistd.h>

#include "efiboot.h"

/*
 * support NVDIMM-P (pmem / btt) devices
 * (does not include NVDIMM-${ANYTHING_ELSE})
 *
 * /sys/dev/block/$major:$minor looks like:
 * 259:0 -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region9/btt9.0/block/pmem9s
 * 259:1 -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region11/btt11.0/block/pmem11s
 * 259:3 -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region11/btt11.0/block/pmem11s/pmem11s1
 *
 * /sys/dev/block/259:0/device looks like:
 * device -> ../../../btt9.0
 * /sys/dev/block/259:1/device looks like:
 * device -> ../../../btt11.0
 *
 * /sys/dev/block/259:1/partition looks like:
 * $ cat partition
 * 1
 *
 * /sys/dev/block/259:0/uuid looks like:
 * $ cat uuid
 * 6e54091e-7476-47ac-824b-b6dd69878661
 *
 * pmem12s -> ../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region12/btt12.1/block/pmem12s
 * dev: 259:0
 * device -> ../../../btt12.1
 * device/uuid: 0cee166e-dd56-4bc2-99d2-2544b69025b8
 * 259:0 -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region12/btt12.1/block/pmem12s
 *
 * pmem12.1s -> ../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region12/btt12.2/block/pmem12.1s
 * dev: 259:1
 * device -> ../../../btt12.2
 * device/uuid: 78d94521-91f7-47db-b3a7-51b764281940
 * 259:1 -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region12/btt12.2/block/pmem12.1s
 *
 * pmem12.2 -> ../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region12/pfn12.1/block/pmem12.2
 * dev: 259:2
 * device -> ../../../pfn12.1
 * device/uuid: 829c5205-89a5-4581-9819-df7d7754c622
 * 259:2 -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region12/pfn12.1/block/pmem12.2
 */

static ssize_t
parse_pmem(struct device *dev, const char *path, const char *root UNUSED)
{
	const char *current = path;
	uint8_t *filebuf = NULL;
	uint8_t system, sysbus, acpi_id;
	uint16_t pnp_id;
	int ndbus, region, btt_region_id, btt_id, rc;
	int pos0 = -1, pos1 = -1;
	char *namespace = NULL;

	debug("entry");

	if (!strcmp(dev->driver, "nd_pmem")) {
	        ;
#if 0 /* dunno */
	} else if (!strcmp(dev->driver, "nd_blk")) {
	        /* dunno */
	        dev->inteface_type = scsi;
#endif
	} else {
	        /*
	         * not a pmem device
	         */
	        return 0;
	}

	/*
	 * We're not actually using any of the values here except pos1 (our
	 * return value), but rather just being paranoid that this is the sort
	 * of device we care about.
	 *
	 * 259:0 -> ../../devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region12/btt12.1/block/pmem12s
	 */
	pos0 = pos1 = -1;
	rc = sscanf(current,
	            "../../devices/%nLNXSYSTM:%hhx/LNXSYBUS:%hhx/ACPI%hx:%hhx/ndbus%d/region%d/btt%d.%d/%n",
	            &pos0, &system, &sysbus, &pnp_id, &acpi_id, &ndbus,
		    &region, &btt_region_id, &btt_id, &pos1);
	debug("current:'%s' rc:%d pos0:%d pos1:%d", current, rc, pos0, pos1);
	dbgmk("         ", pos0, pos1);
	if (rc < 8)
	        return 0;
	current += pos1;

	/*
	 * but the UUID we really do need to have.
	 */
	rc = read_sysfs_file(&filebuf,
	                     "class/block/%s/device/namespace", dev->disk_name);
	if ((rc < 0 && errno == ENOENT) || filebuf == NULL)
	        return -1;

	rc = sscanf((char *)filebuf, "%ms[^\n]\n", &namespace);
	if (rc != 1 || namespace == NULL)
	        return -1;

	filebuf = NULL;
	debug("nvdimm namespace is '%s'", namespace);
	rc = read_sysfs_file(&filebuf, "bus/nd/devices/%s/uuid", namespace);
	free(namespace);
	if (rc < 0 || filebuf == NULL)
	        return -1;

	rc = efi_str_to_guid((char *)filebuf,
	                     &dev->nvdimm_info.namespace_label);
	if (rc < 0)
	        return -1;

	filebuf = NULL;
	rc = read_sysfs_file(&filebuf, "class/block/%s/device/uuid",
	                     dev->disk_name);
	if (rc < 0 || filebuf == NULL)
	        return -1;

	rc = efi_str_to_guid((char *)filebuf,
	                     &dev->nvdimm_info.nvdimm_label);
	if (rc < 0)
	        return -1;

	/*
	 * Right now it's not clear what encoding NVDIMM($uuid) gets in the
	 * binary format, so this will be in the mixed endian format EFI GUIDs
	 * are in (33221100-1100-1100-0011-223344556677) unless you set this
	 * variable.
	 */
	if (getenv("LIBEFIBOOT_SWIZZLE_PMEM_UUID") != NULL) {
	        swizzle_guid_to_uuid(&dev->nvdimm_info.namespace_label);
	        swizzle_guid_to_uuid(&dev->nvdimm_info.nvdimm_label);
	}

	dev->interface_type = nd_pmem;

	debug("current:'%s' sz:%zd", current, current - path);
	return current - path;
}

static ssize_t
dp_create_pmem(struct device *dev,
	       uint8_t *buf, ssize_t size, ssize_t off)
{
	ssize_t sz, sz1;

	debug("entry");

	sz = efidp_make_nvdimm(buf + off, size ? size - off : 0,
	                       &dev->nvdimm_info.namespace_label);
	if (sz < 0)
	        return sz;
	off += sz;
	sz1 = efidp_make_nvdimm(buf + off, size ? size - off : 0,
	                        &dev->nvdimm_info.nvdimm_label);
	if (sz1 < 0)
	        return sz1;

	return sz + sz1;
}

enum interface_type pmem_iftypes[] = { nd_pmem, unknown };

struct dev_probe HIDDEN pmem_parser = {
	.name = "pmem",
	.iftypes = pmem_iftypes,
	.flags = DEV_PROVIDES_ROOT|DEV_PROVIDES_HD,
	.parse = parse_pmem,
	.create = dp_create_pmem,
};

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