fwupd/plugins/mtd/fu-mtd-device.c

/*
 * Copyright (C) 2021 Richard Hughes <richard@hughsie.com>
 *
 * SPDX-License-Identifier: LGPL-2.1+
 */

#include "config.h"

#ifdef HAVE_MTD_USER_H
#include <mtd/mtd-user.h>
#endif

#include "fu-mtd-device.h"

struct _FuMtdDevice {
	FuUdevDevice parent_instance;
	guint64 erasesize;
};

G_DEFINE_TYPE(FuMtdDevice, fu_mtd_device, FU_TYPE_UDEV_DEVICE)

static void
fu_mtd_device_to_string(FuDevice *device, guint idt, GString *str)
{
	FuMtdDevice *self = FU_MTD_DEVICE(device);
	if (self->erasesize > 0)
		fu_common_string_append_kx(str, idt, "EraseSize", self->erasesize);
}

static gboolean
fu_mtd_device_probe(FuDevice *device, GError **error)
{
	FuMtdDevice *self = FU_MTD_DEVICE(device);
	const gchar *name;
	guint64 flags = 0;
	guint64 size = 0;

	/* FuUdevDevice->probe */
	if (!FU_DEVICE_CLASS(fu_mtd_device_parent_class)->probe(device, error))
		return FALSE;

	/* set physical ID */
	if (!fu_udev_device_set_physical_id(FU_UDEV_DEVICE(device), "mtd", error))
		return FALSE;

	/* get name */
	name = fu_udev_device_get_sysfs_attr(FU_UDEV_DEVICE(device), "name", NULL);
	if (name != NULL) {
		g_autofree gchar *devid = NULL;
		g_autofree gchar *name_safe = g_strdup(name);
		g_strdelimit(name_safe, " /\\\"", '-');
		devid = g_strdup_printf("MTD\\NAME_%s", name_safe);
		fu_device_add_instance_id(FU_DEVICE(self), devid);
		fu_device_set_name(FU_DEVICE(self), name);
	}

	/* get properties about the device */
	if (!fu_udev_device_get_sysfs_attr_uint64(FU_UDEV_DEVICE(device), "size", &size, error))
		return FALSE;
	fu_device_set_firmware_size_max(device, size);
	if (!fu_udev_device_get_sysfs_attr_uint64(FU_UDEV_DEVICE(device), "flags", &flags, error))
		return FALSE;
#ifdef HAVE_MTD_USER_H
	if ((flags & MTD_NO_ERASE) == 0) {
		if (!fu_udev_device_get_sysfs_attr_uint64(FU_UDEV_DEVICE(device),
							  "erasesize",
							  &self->erasesize,
							  error))
			return FALSE;
	}
	if (flags & MTD_WRITEABLE)
		fu_device_add_flag(device, FWUPD_DEVICE_FLAG_UPDATABLE);
#endif

	/* success */
	return TRUE;
}

static gboolean
fu_mtd_device_erase(FuMtdDevice *self, GBytes *fw, FuProgress *progress, GError **error)
{
#ifdef HAVE_MTD_USER_H
	g_autoptr(GPtrArray) chunks = fu_chunk_array_new_from_bytes(fw, 0x0, 0x0, self->erasesize);

	/* progress */
	fu_progress_set_id(progress, G_STRLOC);
	fu_progress_set_steps(progress, chunks->len);

	/* erase each chunk */
	for (guint i = 0; i < chunks->len; i++) {
		FuChunk *chk = g_ptr_array_index(chunks, i);
		struct erase_info_user erase = {
		    .start = fu_chunk_get_address(chk),
		    .length = fu_chunk_get_data_sz(chk),
		};
		if (!fu_udev_device_ioctl(FU_UDEV_DEVICE(self), 2, (guint8 *)&erase, NULL, error)) {
			g_prefix_error(error, "failed to erase @0x%x: ", (guint)erase.start);
			return FALSE;
		}
		fu_progress_step_done(progress);
	}

	/* success */
	return TRUE;
#else
	g_set_error_literal(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_NOT_SUPPORTED,
			    "Not supported as mtd-user.h is unavailable");
	return FALSE;
#endif
}

static gboolean
fu_mtd_device_write(FuMtdDevice *self, GPtrArray *chunks, FuProgress *progress, GError **error)
{
	/* progress */
	fu_progress_set_id(progress, G_STRLOC);
	fu_progress_set_steps(progress, chunks->len);

	/* rewind */
	if (!fu_udev_device_seek(FU_UDEV_DEVICE(self), 0x0, error)) {
		g_prefix_error(error, "failed to rewind: ");
		return FALSE;
	}

	/* write each chunk */
	for (guint i = 0; i < chunks->len; i++) {
		FuChunk *chk = g_ptr_array_index(chunks, i);
		if (!fu_udev_device_pwrite_full(FU_UDEV_DEVICE(self),
						0x0,
						fu_chunk_get_data(chk),
						fu_chunk_get_data_sz(chk),
						error)) {
			g_prefix_error(error,
				       "failed to write @0x%x: ",
				       (guint)fu_chunk_get_address(chk));
			return FALSE;
		}
		fu_progress_step_done(progress);
	}

	/* success */
	return TRUE;
}

static gboolean
fu_mtd_device_verify(FuMtdDevice *self, GPtrArray *chunks, FuProgress *progress, GError **error)
{
	/* progress */
	fu_progress_set_id(progress, G_STRLOC);
	fu_progress_set_steps(progress, chunks->len);

	/* verify each chunk */
	for (guint i = 0; i < chunks->len; i++) {
		FuChunk *chk = g_ptr_array_index(chunks, i);
		g_autofree guint8 *buf = g_malloc0(fu_chunk_get_data_sz(chk));
		g_autoptr(GBytes) blob1 = fu_chunk_get_bytes(chk);
		g_autoptr(GBytes) blob2 = NULL;

		if (!fu_udev_device_pread_full(FU_UDEV_DEVICE(self),
					       0x0,
					       buf,
					       fu_chunk_get_data_sz(chk),
					       error)) {
			g_prefix_error(error,
				       "failed to read @0x%x: ",
				       (guint)fu_chunk_get_address(chk));
			return FALSE;
		}
		blob2 = g_bytes_new_static(buf, fu_chunk_get_data_sz(chk));
		if (!fu_common_bytes_compare(blob1, blob2, error)) {
			g_prefix_error(error,
				       "failed to verify @0x%x: ",
				       (guint)fu_chunk_get_address(chk));
			return FALSE;
		}
		fu_progress_step_done(progress);
	}

	/* success */
	return TRUE;
}

static gboolean
fu_mtd_device_write_verify(FuMtdDevice *self, GBytes *fw, FuProgress *progress, GError **error)
{
	g_autoptr(GPtrArray) chunks = fu_chunk_array_new_from_bytes(fw, 0x0, 0x0, 10 * 1024);

	/* progress */
	fu_progress_set_id(progress, G_STRLOC);
	fu_progress_add_flag(progress, FU_PROGRESS_FLAG_GUESSED);
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_WRITE, 50);
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_VERIFY, 50);

	/* write */
	if (!fu_mtd_device_write(self, chunks, fu_progress_get_child(progress), error))
		return FALSE;
	fu_progress_step_done(progress);

	/* verify */
	if (!fu_mtd_device_verify(self, chunks, fu_progress_get_child(progress), error))
		return FALSE;
	fu_progress_step_done(progress);

	/* success */
	return TRUE;
}

static gboolean
fu_mtd_device_write_firmware(FuDevice *device,
			     FuFirmware *firmware,
			     FuProgress *progress,
			     FwupdInstallFlags flags,
			     GError **error)
{
	FuMtdDevice *self = FU_MTD_DEVICE(device);
	g_autoptr(GBytes) fw = NULL;

	/* get data to write */
	fw = fu_firmware_get_bytes(firmware, error);
	if (fw == NULL)
		return FALSE;
	if (g_bytes_get_size(fw) > fu_device_get_firmware_size_max(device)) {
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_INVALID_FILE,
			    "firmware too large, got 0x%x, expected <= 0x%x",
			    (guint)g_bytes_get_size(fw),
			    (guint)fu_device_get_firmware_size_max(device));
		return FALSE;
	}

	/* just one step required */
	if (self->erasesize == 0)
		return fu_mtd_device_write_verify(self, fw, progress, error);

	/* progress */
	fu_progress_set_id(progress, G_STRLOC);
	fu_progress_add_flag(progress, FU_PROGRESS_FLAG_GUESSED);
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_ERASE, 50);
	fu_progress_add_step(progress, FWUPD_STATUS_DEVICE_WRITE, 50);

	/* erase */
	if (!fu_mtd_device_erase(self, fw, fu_progress_get_child(progress), error))
		return FALSE;
	fu_progress_step_done(progress);

	/* write */
	if (!fu_mtd_device_write_verify(self, fw, fu_progress_get_child(progress), error))
		return FALSE;
	fu_progress_step_done(progress);

	/* success */
	return TRUE;
}

static void
fu_mtd_device_init(FuMtdDevice *self)
{
	fu_udev_device_set_flags(FU_UDEV_DEVICE(self),
				 FU_UDEV_DEVICE_FLAG_OPEN_READ | FU_UDEV_DEVICE_FLAG_OPEN_WRITE |
				     FU_UDEV_DEVICE_FLAG_OPEN_SYNC);
}

static void
fu_mtd_device_class_init(FuMtdDeviceClass *klass)
{
	FuDeviceClass *klass_device = FU_DEVICE_CLASS(klass);
	klass_device->probe = fu_mtd_device_probe;
	klass_device->to_string = fu_mtd_device_to_string;
	klass_device->write_firmware = fu_mtd_device_write_firmware;
}