/*
 * Copyright (C) 2015 Richard Hughes <richard@hughsie.com>
 *
 * SPDX-License-Identifier: LGPL-2.1+
 */

#define G_LOG_DOMAIN "FuFirmware"

#include "config.h"

#include <string.h>

#include "fu-byte-array.h"
#include "fu-bytes.h"
#include "fu-chunk-private.h"
#include "fu-common.h"
#include "fu-dfu-firmware-private.h"
#include "fu-dfuse-firmware.h"
#include "fu-mem.h"

/**
 * FuDfuseFirmware:
 *
 * A DfuSe firmware image.
 *
 * See also: [class@FuDfuFirmware]
 */

G_DEFINE_TYPE(FuDfuseFirmware, fu_dfuse_firmware, FU_TYPE_DFU_FIRMWARE)

/* firmware: LE */
typedef struct __attribute__((packed)) {
	guint8 sig[5];
	guint8 ver;
	guint32 image_size;
	guint8 targets;
} DfuSeHdr;

/* image: LE */
typedef struct __attribute__((packed)) {
	guint8 sig[6];
	guint8 alt_setting;
	guint32 target_named;
	gchar target_name[255];
	guint32 target_size;
	guint32 chunks;
} DfuSeImageHdr;

/* element: LE */
typedef struct __attribute__((packed)) {
	guint32 address;
	guint32 size;
} DfuSeElementHdr;

G_STATIC_ASSERT(sizeof(DfuSeHdr) == 11);
G_STATIC_ASSERT(sizeof(DfuSeImageHdr) == 274);
G_STATIC_ASSERT(sizeof(DfuSeElementHdr) == 8);

static FuChunk *
fu_firmware_image_chunk_parse(FuDfuseFirmware *self, GBytes *bytes, gsize *offset, GError **error)
{
	DfuSeElementHdr hdr = {0x0};
	gsize bufsz = 0;
	gsize ftrlen = fu_dfu_firmware_get_footer_len(FU_DFU_FIRMWARE(self));
	const guint8 *buf = g_bytes_get_data(bytes, &bufsz);
	g_autoptr(FuChunk) chk = NULL;
	g_autoptr(GBytes) blob = NULL;

	/* check size */
	if (!fu_memcpy_safe((guint8 *)&hdr,
			    sizeof(hdr),
			    0x0, /* dst */
			    buf,
			    bufsz - ftrlen,
			    *offset, /* src */
			    sizeof(hdr),
			    error))
		return NULL;

	/* create new chunk */
	*offset += sizeof(hdr);
	blob = fu_bytes_new_offset(bytes, *offset, GUINT32_FROM_LE(hdr.size), error);
	if (blob == NULL)
		return NULL;
	chk = fu_chunk_bytes_new(blob);
	fu_chunk_set_address(chk, GUINT32_FROM_LE(hdr.address));
	*offset += fu_chunk_get_data_sz(chk);

	/* success */
	return g_steal_pointer(&chk);
}

static FuFirmware *
fu_dfuse_firmware_image_parse(FuDfuseFirmware *self, GBytes *bytes, gsize *offset, GError **error)
{
	DfuSeImageHdr hdr = {0x0};
	gsize bufsz = 0;
	const guint8 *buf = g_bytes_get_data(bytes, &bufsz);
	g_autoptr(FuFirmware) image = fu_firmware_new();

	/* verify image signature */
	if (!fu_memcpy_safe((guint8 *)&hdr,
			    sizeof(hdr),
			    0x0, /* dst */
			    buf,
			    bufsz,
			    *offset, /* src */
			    sizeof(hdr),
			    error))
		return NULL;
	if (memcmp(hdr.sig, "Target", sizeof(hdr.sig)) != 0) {
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_INVALID_FILE,
				    "invalid DfuSe target signature");
		return NULL;
	}

	/* set properties */
	fu_firmware_set_idx(image, hdr.alt_setting);
	if (GUINT32_FROM_LE(hdr.target_named) == 0x01) {
		g_autofree gchar *img_id = NULL;
		img_id = g_strndup(hdr.target_name, sizeof(hdr.target_name));
		fu_firmware_set_id(image, img_id);
	}

	/* no chunks */
	if (hdr.chunks == 0) {
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_INVALID_FILE,
				    "DfuSe image has no chunks");
		return NULL;
	}

	/* parse chunks */
	*offset += sizeof(hdr);
	for (guint j = 0; j < GUINT32_FROM_LE(hdr.chunks); j++) {
		g_autoptr(FuChunk) chk = NULL;
		chk = fu_firmware_image_chunk_parse(self, bytes, offset, error);
		if (chk == NULL)
			return NULL;
		fu_firmware_add_chunk(image, chk);
	}

	/* success */
	return g_steal_pointer(&image);
}

static gboolean
fu_dfuse_firmware_check_magic(FuFirmware *firmware, GBytes *fw, gsize offset, GError **error)
{
	guint8 magic[5] = {0x0};

	if (!fu_memcpy_safe(magic,
			    sizeof(magic),
			    0x0, /* dst */
			    g_bytes_get_data(fw, NULL),
			    g_bytes_get_size(fw),
			    offset, /* src */
			    sizeof(magic),
			    error)) {
		g_prefix_error(error, "failed to read magic: ");
		return FALSE;
	}
	if (memcmp(magic, "DfuSe", sizeof(magic)) != 0) {
		g_set_error_literal(error,
				    FWUPD_ERROR,
				    FWUPD_ERROR_INVALID_FILE,
				    "invalid DfuSe prefix");
		return FALSE;
	}

	/* success */
	return TRUE;
}

static gboolean
fu_dfuse_firmware_parse(FuFirmware *firmware,
			GBytes *fw,
			gsize offset,
			FwupdInstallFlags flags,
			GError **error)
{
	FuDfuFirmware *dfu_firmware = FU_DFU_FIRMWARE(firmware);
	gsize bufsz = 0;
	guint32 image_size = 0;
	guint8 targets = 0;
	guint8 ver = 0;
	const guint8 *buf = g_bytes_get_data(fw, &bufsz);

	/* DFU footer first */
	if (!fu_dfu_firmware_parse_footer(dfu_firmware, fw, flags, error))
		return FALSE;

	/* check the version */
	if (!fu_memread_uint8_safe(buf,
				   bufsz,
				   offset + G_STRUCT_OFFSET(DfuSeHdr, ver),
				   &ver,
				   error))
		return FALSE;
	if (ver != 0x01) {
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_INTERNAL,
			    "invalid DfuSe version, got %02x",
			    ver);
		return FALSE;
	}

	/* check image size */
	if (!fu_memread_uint32_safe(buf,
				    bufsz,
				    offset + G_STRUCT_OFFSET(DfuSeHdr, image_size),
				    &image_size,
				    G_LITTLE_ENDIAN,
				    error))
		return FALSE;
	if (image_size != bufsz - fu_dfu_firmware_get_footer_len(dfu_firmware)) {
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_INTERNAL,
			    "invalid DfuSe image size, "
			    "got %" G_GUINT32_FORMAT ", "
			    "expected %" G_GSIZE_FORMAT,
			    image_size,
			    bufsz - fu_dfu_firmware_get_footer_len(dfu_firmware));
		return FALSE;
	}

	/* parse the image targets */
	if (!fu_memread_uint8_safe(buf,
				   bufsz,
				   offset + G_STRUCT_OFFSET(DfuSeHdr, targets),
				   &targets,
				   error))
		return FALSE;
	offset += sizeof(DfuSeHdr);
	for (guint i = 0; i < targets; i++) {
		g_autoptr(FuFirmware) image = NULL;
		image =
		    fu_dfuse_firmware_image_parse(FU_DFUSE_FIRMWARE(firmware), fw, &offset, error);
		if (image == NULL)
			return FALSE;
		fu_firmware_add_image(firmware, image);
	}
	return TRUE;
}

static GBytes *
fu_firmware_chunk_write(FuChunk *chk)
{
	DfuSeElementHdr hdr = {0x0};
	const guint8 *data = fu_chunk_get_data(chk);
	gsize length = fu_chunk_get_data_sz(chk);
	g_autoptr(GByteArray) buf = NULL;

	buf = g_byte_array_sized_new(sizeof(DfuSeElementHdr) + length);
	hdr.address = GUINT32_TO_LE(fu_chunk_get_address(chk));
	hdr.size = GUINT32_TO_LE(length);
	g_byte_array_append(buf, (const guint8 *)&hdr, sizeof(hdr));
	g_byte_array_append(buf, data, length);
	return g_byte_array_free_to_bytes(g_steal_pointer(&buf));
}

static GBytes *
fu_dfuse_firmware_write_image(FuFirmware *image, GError **error)
{
	DfuSeImageHdr hdr = {0x0};
	gsize totalsz = 0;
	g_autoptr(GByteArray) buf = NULL;
	g_autoptr(GPtrArray) blobs = NULL;
	g_autoptr(GPtrArray) chunks = NULL;

	/* get total size */
	blobs = g_ptr_array_new_with_free_func((GDestroyNotify)g_bytes_unref);
	chunks = fu_firmware_get_chunks(image, error);
	if (chunks == NULL)
		return NULL;
	for (guint i = 0; i < chunks->len; i++) {
		FuChunk *chk = g_ptr_array_index(chunks, i);
		GBytes *bytes = fu_firmware_chunk_write(chk);
		g_ptr_array_add(blobs, bytes);
		totalsz += g_bytes_get_size(bytes);
	}

	/* mutable output buffer */
	buf = g_byte_array_sized_new(sizeof(DfuSeImageHdr) + totalsz);

	/* add prefix */
	memcpy(hdr.sig, "Target", 6);
	hdr.alt_setting = fu_firmware_get_idx(image);
	if (fu_firmware_get_id(image) != NULL) {
		hdr.target_named = GUINT32_TO_LE(0x01);
		(void)g_strlcpy((gchar *)&hdr.target_name,
				fu_firmware_get_id(image),
				sizeof(hdr.target_name));
	}
	hdr.target_size = GUINT32_TO_LE(totalsz);
	hdr.chunks = GUINT32_TO_LE(chunks->len);
	g_byte_array_append(buf, (const guint8 *)&hdr, sizeof(hdr));

	/* copy data */
	for (guint i = 0; i < blobs->len; i++) {
		GBytes *blob = g_ptr_array_index(blobs, i);
		fu_byte_array_append_bytes(buf, blob);
	}
	return g_byte_array_free_to_bytes(g_steal_pointer(&buf));
}

static GBytes *
fu_dfuse_firmware_write(FuFirmware *firmware, GError **error)
{
	DfuSeHdr hdr = {0x0};
	gsize totalsz = 0;
	g_autoptr(GByteArray) buf = NULL;
	g_autoptr(GBytes) blob_noftr = NULL;
	g_autoptr(GPtrArray) blobs = NULL;
	g_autoptr(GPtrArray) images = NULL;

	/* create mutable output buffer */
	blobs = g_ptr_array_new_with_free_func((GDestroyNotify)g_bytes_unref);
	images = fu_firmware_get_images(FU_FIRMWARE(firmware));
	for (guint i = 0; i < images->len; i++) {
		FuFirmware *img = g_ptr_array_index(images, i);
		g_autoptr(GBytes) blob = NULL;
		blob = fu_dfuse_firmware_write_image(img, error);
		if (blob == NULL)
			return NULL;
		totalsz += g_bytes_get_size(blob);
		g_ptr_array_add(blobs, g_steal_pointer(&blob));
	}
	buf = g_byte_array_sized_new(sizeof(DfuSeHdr) + totalsz);

	/* DfuSe header */
	memcpy(hdr.sig, "DfuSe", 5);
	hdr.ver = 0x01;
	hdr.image_size = GUINT32_TO_LE(sizeof(hdr) + totalsz);
	if (images->len > G_MAXUINT8) {
		g_set_error(error,
			    FWUPD_ERROR,
			    FWUPD_ERROR_INTERNAL,
			    "too many (%u) images to write DfuSe file",
			    images->len);
		return NULL;
	}
	hdr.targets = (guint8)images->len;
	g_byte_array_append(buf, (const guint8 *)&hdr, sizeof(hdr));

	/* copy images */
	for (guint i = 0; i < blobs->len; i++) {
		GBytes *blob = g_ptr_array_index(blobs, i);
		fu_byte_array_append_bytes(buf, blob);
	}

	/* return blob */
	blob_noftr = g_byte_array_free_to_bytes(g_steal_pointer(&buf));
	return fu_dfu_firmware_append_footer(FU_DFU_FIRMWARE(firmware), blob_noftr, error);
}

static void
fu_dfuse_firmware_init(FuDfuseFirmware *self)
{
	fu_dfu_firmware_set_version(FU_DFU_FIRMWARE(self), FU_DFU_FIRMARE_VERSION_DFUSE);
}

static void
fu_dfuse_firmware_class_init(FuDfuseFirmwareClass *klass)
{
	FuFirmwareClass *klass_firmware = FU_FIRMWARE_CLASS(klass);
	klass_firmware->check_magic = fu_dfuse_firmware_check_magic;
	klass_firmware->parse = fu_dfuse_firmware_parse;
	klass_firmware->write = fu_dfuse_firmware_write;
}

/**
 * fu_dfuse_firmware_new:
 *
 * Creates a new #FuFirmware of sub type DfuSe
 *
 * Since: 1.5.6
 **/
FuFirmware *
fu_dfuse_firmware_new(void)
{
	return FU_FIRMWARE(g_object_new(FU_TYPE_DFUSE_FIRMWARE, NULL));
}