/*

 * Copyright 2025 Richard Hughes <richard@hughsie.com>

 *

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

 */

#define G_LOG_DOMAIN "FuEfiVss2VariableStore"

#include "config.h"

#include "fu-byte-array.h"

#include "fu-common.h"

#include "fu-efi-struct.h"

#include "fu-efi-vss-auth-variable.h"

#include "fu-efi-vss2-variable-store.h"

#include "fu-input-stream.h"

#include "fu-string.h"

/**

 * FuEfiVss2VariableStore:

 *

 * A NVRAM variable store.

 *

 * See also: [class@FuFirmware]

 */

struct _FuEfiVss2VariableStore {

  FuFirmware parent_instance;

};

G_DEFINE_TYPE(FuEfiVss2VariableStore, fu_efi_vss2_variable_store, FU_TYPE_FIRMWARE)

static gboolean

fu_efi_vss2_variable_store_validate(FuFirmware *firmware,

            FuInputStream *stream,

            gsize offset,

            GError **error)

{

  return fu_struct_efi_vss2_variable_store_header_validate_stream(stream, offset, error);

}

static gboolean

fu_efi_vss2_variable_store_parse(FuFirmware *firmware,

         FuInputStream *stream,

         FuFirmwareParseFlags flags,

         GError **error)

{

  gsize offset = 0x0;

  g_autoptr(FuStructEfiVss2VariableStoreHeader) st = NULL;

  st = fu_struct_efi_vss2_variable_store_header_parse_stream(stream, offset, error);

  if (st == NULL)

    return FALSE;

  /* sanity check */

  if (fu_struct_efi_vss2_variable_store_header_get_size(st) >

      fu_firmware_get_size_max(firmware)) {

    g_set_error(error,

          FWUPD_ERROR,

          FWUPD_ERROR_INTERNAL,

          "VSS store larger than max size: 0x%x > 0x%x",

          (guint)fu_struct_efi_vss2_variable_store_header_get_size(st),

          (guint)fu_firmware_get_size_max(firmware));

    return FALSE;

  }

  /* parse each attr */

  if (!fu_size_checked_inc(&offset, st->buf->len, error)) {

    g_prefix_error_literal(error, "VSS2 header offset overflow: ");

    return FALSE;

  }

  while (offset < fu_struct_efi_vss2_variable_store_header_get_size(st)) {

    g_autoptr(FuFirmware) img = fu_efi_vss_auth_variable_new();

    if (!fu_firmware_parse_stream(img, stream, offset, flags, error)) {

      g_prefix_error(error, "offset @0x%x: ", (guint)offset);

      return FALSE;

    }

    if (fu_firmware_has_flag(img, FU_FIRMWARE_FLAG_IS_LAST_IMAGE))

      break;

    if (fu_firmware_get_size(img) == 0) {

      g_set_error_literal(error,

              FWUPD_ERROR,

              FWUPD_ERROR_INTERNAL,

              "VSS2 store entry has zero size");

      return FALSE;

    }

    if (fu_efi_vss_auth_variable_get_state(FU_EFI_VSS_AUTH_VARIABLE(img)) ==

        FU_EFI_VARIABLE_STATE_VARIABLE_ADDED) {

      fu_firmware_set_offset(img, offset);

      if (!fu_firmware_add_image(firmware, img, error))

        return FALSE;

    }

    if (!fu_size_checked_inc(&offset, fu_firmware_get_size(img), error))

      return FALSE;

    offset = fu_common_align_up(offset, FU_FIRMWARE_ALIGNMENT_4);

  }

  /* success */

  fu_firmware_set_size(firmware, fu_struct_efi_vss2_variable_store_header_get_size(st));

  return TRUE;

}

static GByteArray *

fu_efi_vss2_variable_store_write(FuFirmware *firmware, GError **error)

{

  g_autoptr(FuStructEfiVss2VariableStoreHeader) st =

      fu_struct_efi_vss2_variable_store_header_new();

  g_autoptr(GPtrArray) imgs = fu_firmware_get_images(firmware);

  /* sanity check */

  if (fu_firmware_get_size(firmware) < st->buf->len) {

    g_set_error_literal(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INTERNAL,

            "VSS2 variable store has zero size");

    return NULL;

  }

  /* each attr */

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

    FuFirmware *img = g_ptr_array_index(imgs, i);

    g_autoptr(GBytes) fw = NULL;

    fw = fu_firmware_write(img, error);

    if (fw == NULL)

      return NULL;

    fu_byte_array_append_bytes(st->buf, fw);

    fu_byte_array_align_up(st->buf, FU_FIRMWARE_ALIGNMENT_4, 0xFF);

  }

  /* sanity check */

  if (st->buf->len > fu_firmware_get_size(firmware)) {

    g_set_error(error,

          FWUPD_ERROR,

          FWUPD_ERROR_INTERNAL,

          "VSS2 store is too small, needed 0x%x but defined as 0x%x",

          st->buf->len,

          (guint)(fu_firmware_get_size(firmware)));

    return NULL;

  }

  /* fix up header and attrs */

  fu_byte_array_set_size(st->buf, fu_firmware_get_size(firmware), 0xFF);

  fu_struct_efi_vss2_variable_store_header_set_size(st, fu_firmware_get_size(firmware));

  /* success */

  return g_steal_pointer(&st->buf);

}

static void

fu_efi_vss2_variable_store_init(FuEfiVss2VariableStore *self)

{

  fu_firmware_add_flag(FU_FIRMWARE(self), FU_FIRMWARE_FLAG_DEDUPE_ID);

  fu_firmware_add_flag(FU_FIRMWARE(self), FU_FIRMWARE_FLAG_HAS_STORED_SIZE);

}

static void

fu_efi_vss2_variable_store_class_init(FuEfiVss2VariableStoreClass *klass)

{

  FuFirmwareClass *firmware_class = FU_FIRMWARE_CLASS(klass);

  firmware_class->validate = fu_efi_vss2_variable_store_validate;

  firmware_class->parse = fu_efi_vss2_variable_store_parse;

  firmware_class->write = fu_efi_vss2_variable_store_write;

  fu_firmware_add_image_gtype(firmware_class, FU_TYPE_EFI_VSS_AUTH_VARIABLE);

#ifdef HAVE_FUZZER

  fu_firmware_set_size_max(firmware_class, 4 * FU_KB);

  fu_firmware_set_images_max(firmware_class, 10);

#else

  fu_firmware_set_size_max(firmware_class, 16 * FU_MB);

  fu_firmware_set_images_max(firmware_class, 10000);

#endif

}

/**

 * fu_efi_vss2_variable_store_new:

 *

 * Creates an empty VSS variable store.

 *

 * Returns: a #FuFirmware

 *

 * Since: 2.0.17

 **/

FuFirmware *

fu_efi_vss2_variable_store_new(void)

{

  return g_object_new(FU_TYPE_EFI_VSS2_VARIABLE_STORE, NULL);

}