/*

 * Copyright 2020 Richard Hughes <richard@hughsie.com>

 *

 * SPDX-License-Identifier: LGPL-2.1-or-later

 */

#include "config.h"

#include "fu-byte-array.h"

#include "fu-common.h"

#include "fu-efi-common.h"

#include "fu-efi-file.h"

#include "fu-efi-section.h"

#include "fu-efi-struct.h"

#include "fu-input-stream.h"

#include "fu-partial-input-stream.h"

#include "fu-sum.h"

/**

 * FuEfiFile:

 *

 * A UEFI file.

 *

 * See also: [class@FuFirmware]

 */

typedef struct {

  guint8 type;

  guint8 attrib;

} FuEfiFilePrivate;

G_DEFINE_TYPE_WITH_PRIVATE(FuEfiFile, fu_efi_file, FU_TYPE_FIRMWARE)

#define GET_PRIVATE(o) (fu_efi_file_get_instance_private(o))

#define FU_EFI_FILE_SIZE_MAX 0x1000000 /* 16 MB */

static void

fu_efi_file_export(FuFirmware *firmware, FuFirmwareExportFlags flags, XbBuilderNode *bn)

{

  FuEfiFile *self = FU_EFI_FILE(firmware);

  FuEfiFilePrivate *priv = GET_PRIVATE(self);

  fu_xmlb_builder_insert_kx(bn, "attrib", priv->attrib);

  fu_xmlb_builder_insert_kx(bn, "type", priv->type);

  if (flags & FU_FIRMWARE_EXPORT_FLAG_INCLUDE_DEBUG) {

    fu_xmlb_builder_insert_kv(bn,

            "name",

            fu_efi_guid_to_name(fu_firmware_get_id(firmware)));

    fu_xmlb_builder_insert_kv(bn, "type_name", fu_efi_file_type_to_string(priv->type));

  }

}

static guint8

fu_efi_file_hdr_checksum8(GBytes *blob)

{

  gsize bufsz = 0;

  guint8 checksum = 0;

  const guint8 *buf = g_bytes_get_data(blob, &bufsz);

  for (gsize i = 0; i < bufsz; i++) {

    if (i == FU_STRUCT_EFI_FILE_OFFSET_HDR_CHECKSUM)

      continue;

    if (i == FU_STRUCT_EFI_FILE_OFFSET_DATA_CHECKSUM)

      continue;

    if (i == FU_STRUCT_EFI_FILE_OFFSET_STATE)

      continue;

    checksum += buf[i];

  }

  return (guint8)(0x100u - (guint)checksum);

}

static gboolean

fu_efi_file_parse(FuFirmware *firmware,

      GInputStream *stream,

      FuFirmwareParseFlags flags,

      GError **error)

{

  FuEfiFile *self = FU_EFI_FILE(firmware);

  FuEfiFilePrivate *priv = GET_PRIVATE(self);

  guint32 size = 0x0;

  g_autofree gchar *guid_str = NULL;

  g_autoptr(FuStructEfiFile) st = NULL;

  g_autoptr(GInputStream) partial_stream = NULL;

  /* parse */

  st = fu_struct_efi_file_parse_stream(stream, 0x0, error);

  if (st == NULL)

    return FALSE;

  priv->type = fu_struct_efi_file_get_type(st);

  priv->attrib = fu_struct_efi_file_get_attrs(st);

  guid_str =

      fwupd_guid_to_string(fu_struct_efi_file_get_name(st), FWUPD_GUID_FLAG_MIXED_ENDIAN);

  fu_firmware_set_id(firmware, guid_str);

  /* extended size exists so size must be set to zero */

  if (priv->attrib & FU_EFI_FILE_ATTRIB_LARGE_FILE) {

    if (fu_struct_efi_file_get_size(st) != 0) {

      g_set_error(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INTERNAL,

            "invalid FFS size -- expected 0x0 and got 0x%x",

            (guint)fu_struct_efi_file_get_size(st));

      return FALSE;

    }

    fu_struct_efi_file_unref(st);

    st = (FuStructEfiFile *)fu_struct_efi_file2_parse_stream(stream, 0x0, error);

    if (st == NULL)

      return FALSE;

    size = fu_struct_efi_file2_get_extended_size((FuStructEfiFile2 *)st);

  } else {

    size = fu_struct_efi_file_get_size(st);

  }

  if (size < st->buf->len) {

    g_set_error(error,

          FWUPD_ERROR,

          FWUPD_ERROR_INTERNAL,

          "invalid FFS length, got 0x%x",

          (guint)size);

    return FALSE;

  }

  /* verify header checksum */

  if ((flags & FU_FIRMWARE_PARSE_FLAG_IGNORE_CHECKSUM) == 0) {

    guint8 hdr_checksum_verify;

    g_autoptr(GBytes) hdr_blob = NULL;

    hdr_blob = fu_input_stream_read_bytes(stream, 0x0, st->buf->len, NULL, error);

    if (hdr_blob == NULL)

      return FALSE;

    hdr_checksum_verify = fu_efi_file_hdr_checksum8(hdr_blob);

    if (hdr_checksum_verify != fu_struct_efi_file_get_hdr_checksum(st)) {

      g_set_error(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INVALID_FILE,

            "checksum invalid, got %02x, expected %02x",

            hdr_checksum_verify,

            fu_struct_efi_file_get_hdr_checksum(st));

      return FALSE;

    }

  }

  /* add simple blob */

  partial_stream =

      fu_partial_input_stream_new(stream, st->buf->len, size - st->buf->len, error);

  if (partial_stream == NULL) {

    g_prefix_error_literal(error, "failed to cut EFI blob: ");

    return FALSE;

  }

  /* verify data checksum */

  if ((priv->attrib & FU_EFI_FILE_ATTRIB_CHECKSUM) > 0 &&

      (flags & FU_FIRMWARE_PARSE_FLAG_IGNORE_CHECKSUM) == 0) {

    guint8 data_checksum_verify = 0;

    if (!fu_input_stream_compute_sum8(partial_stream, &data_checksum_verify, error))

      return FALSE;

    if (0x100 - data_checksum_verify != fu_struct_efi_file_get_data_checksum(st)) {

      g_set_error(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INVALID_FILE,

            "checksum invalid, got 0x%02x, expected 0x%02x",

            0x100u - data_checksum_verify,

            fu_struct_efi_file_get_data_checksum(st));

      return FALSE;

    }

  }

  /* add sections */

  if (priv->type != FU_EFI_FILE_TYPE_FFS_PAD && priv->type != FU_EFI_FILE_TYPE_RAW) {

    if (!fu_efi_parse_sections(firmware, partial_stream, 0, flags, error)) {

      g_prefix_error_literal(error, "failed to add firmware image: ");

      return FALSE;

    }

  } else {

    if (!fu_firmware_set_stream(firmware, partial_stream, error))

      return FALSE;

  }

  /* align size for volume */

  fu_firmware_set_size(firmware,

           fu_common_align_up(size, fu_firmware_get_alignment(firmware)));

  /* success */

  return TRUE;

}

static GBytes *

fu_efi_file_write_sections(FuEfiFile *self, GError **error)

{

  g_autoptr(GPtrArray) images = fu_firmware_get_images(FU_FIRMWARE(self));

  g_autoptr(GByteArray) buf = g_byte_array_new();

  /* sanity check */

  if (fu_firmware_get_alignment(FU_FIRMWARE(self)) > FU_FIRMWARE_ALIGNMENT_1M) {

    g_set_error(error,

          FWUPD_ERROR,

          FWUPD_ERROR_INVALID_FILE,

          "alignment invalid, got 0x%02x",

          fu_firmware_get_alignment(FU_FIRMWARE(self)));

    return NULL;

  }

  /* no sections defined */

  if (images->len == 0)

    return fu_firmware_get_bytes_with_patches(FU_FIRMWARE(self), error);

  /* add each section */

  for (guint i = 0; i < images->len; i++) {

    FuFirmware *img = g_ptr_array_index(images, i);

    g_autoptr(GBytes) blob = NULL;

    fu_firmware_set_offset(img, buf->len);

    blob = fu_firmware_write(img, error);

    if (blob == NULL)

      return NULL;

    fu_byte_array_append_bytes(buf, blob);

    fu_byte_array_align_up(buf, FU_FIRMWARE_ALIGNMENT_4, 0xFF);

    /* sanity check */

    if (buf->len > FU_EFI_FILE_SIZE_MAX) {

      g_set_error(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INVALID_FILE,

            "EFI file too large, 0x%02x > 0x%02x",

            (guint)buf->len,

            (guint)FU_EFI_FILE_SIZE_MAX);

      return NULL;

    }

  }

  /* success */

  return g_bytes_new(buf->data, buf->len);

}

static GByteArray *

fu_efi_file_write(FuFirmware *firmware, GError **error)

{

  FuEfiFile *self = FU_EFI_FILE(firmware);

  FuEfiFilePrivate *priv = GET_PRIVATE(self);

  fwupd_guid_t guid = {0x0};

  g_autoptr(FuStructEfiFile) st = fu_struct_efi_file_new();

  g_autoptr(GBytes) blob = NULL;

  g_autoptr(GBytes) hdr_blob = NULL;

  /* simple blob for now */

  blob = fu_efi_file_write_sections(self, error);

  if (blob == NULL)

    return NULL;

  if (fu_firmware_get_id(firmware) != NULL) {

    if (!fwupd_guid_from_string(fu_firmware_get_id(firmware),

              &guid,

              FWUPD_GUID_FLAG_MIXED_ENDIAN,

              error))

      return NULL;

  }

  fu_struct_efi_file_set_name(st, &guid);

  fu_struct_efi_file_set_hdr_checksum(st, 0x0);

  fu_struct_efi_file_set_data_checksum(st, 0x100 - fu_sum8_bytes(blob));

  fu_struct_efi_file_set_type(st, priv->type);

  fu_struct_efi_file_set_attrs(st, priv->attrib);

  fu_struct_efi_file_set_size(st, g_bytes_get_size(blob) + st->buf->len);

  /* fix up header checksum */

  hdr_blob = g_bytes_new_static(st->buf->data, st->buf->len);

  fu_struct_efi_file_set_hdr_checksum(st, fu_efi_file_hdr_checksum8(hdr_blob));

  /* success */

  fu_byte_array_append_bytes(st->buf, blob);

  return g_steal_pointer(&st->buf);

}

static gboolean

fu_efi_file_build(FuFirmware *firmware, XbNode *n, GError **error)

{

  FuEfiFile *self = FU_EFI_FILE(firmware);

  FuEfiFilePrivate *priv = GET_PRIVATE(self);

  guint64 tmp;

  /* simple properties */

  tmp = xb_node_query_text_as_uint(n, "type", NULL);

  if (tmp != G_MAXUINT64 && tmp <= G_MAXUINT8)

    priv->type = tmp;

  tmp = xb_node_query_text_as_uint(n, "attrib", NULL);

  if (tmp != G_MAXUINT64 && tmp <= G_MAXUINT8)

    priv->attrib = tmp;

  /* success */

  return TRUE;

}

static void

fu_efi_file_init(FuEfiFile *self)

{

  FuEfiFilePrivate *priv = GET_PRIVATE(self);

  priv->attrib = FU_EFI_FILE_ATTRIB_NONE;

  priv->type = FU_EFI_FILE_TYPE_RAW;

  fu_firmware_set_alignment(FU_FIRMWARE(self), FU_FIRMWARE_ALIGNMENT_8);

  g_type_ensure(FU_TYPE_EFI_SECTION);

}

static void

fu_efi_file_class_init(FuEfiFileClass *klass)

{

  FuFirmwareClass *firmware_class = FU_FIRMWARE_CLASS(klass);

  firmware_class->parse = fu_efi_file_parse;

  firmware_class->write = fu_efi_file_write;

  firmware_class->build = fu_efi_file_build;

  firmware_class->export = fu_efi_file_export;

}

/**

 * fu_efi_file_new:

 *

 * Creates a new #FuFirmware

 *

 * Since: 2.0.0

 **/

FuFirmware *

fu_efi_file_new(void)

{

  return FU_FIRMWARE(g_object_new(FU_TYPE_EFI_FILE, NULL));

}