/*

 * Copyright 2021 Richard Hughes <richard@hughsie.com>

 *

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

 */

#include "config.h"

#include "fu-byte-array.h"

#include "fu-efi-file.h"

#include "fu-efi-filesystem.h"

#include "fu-input-stream.h"

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

/**

 * FuEfiFilesystem:

 *

 * A UEFI filesystem.

 *

 * See also: [class@FuFirmware]

 */

G_DEFINE_TYPE(FuEfiFilesystem, fu_efi_filesystem, FU_TYPE_FIRMWARE)

#define FU_EFI_FILESYSTEM_FILES_MAX 10000

#define FU_EFI_FILESYSTEM_SIZE_MAX  0x10000000 /* 256 MB */

static gboolean

fu_efi_filesystem_parse(FuFirmware *firmware,

      GInputStream *stream,

      FuFirmwareParseFlags flags,

      GError **error)

{

  gsize offset = 0;

  gsize streamsz = 0;

  if (!fu_input_stream_size(stream, &streamsz, error))

    return FALSE;

  while (offset < streamsz) {

    g_autoptr(FuFirmware) img = fu_efi_file_new();

    g_autoptr(GInputStream) stream_tmp = NULL;

    gboolean is_freespace = TRUE;

    /* ignore free space */

    for (guint i = 0; i < 0x18; i++) {

      guint8 tmp = 0;

      if (!fu_input_stream_read_u8(stream, offset + i, &tmp, error))

        return FALSE;

      if (tmp != 0xff) {

        is_freespace = FALSE;

        break;

      }

    }

    if (is_freespace) {

      g_debug("ignoring free space @0x%x of 0x%x",

        (guint)offset,

        (guint)streamsz);

      break;

    }

    stream_tmp = fu_partial_input_stream_new(stream, offset, streamsz - offset, error);

    if (stream_tmp == NULL) {

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

      return FALSE;

    }

    if (!fu_firmware_parse_stream(img,

                stream_tmp,

                0x0,

                flags | FU_FIRMWARE_PARSE_FLAG_NO_SEARCH,

                error)) {

      g_prefix_error(error, "failed to parse EFI file at 0x%x: ", (guint)offset);

      return FALSE;

    }

    fu_firmware_set_offset(firmware, offset);

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

      return FALSE;

    /* next! */

    offset += fu_firmware_get_size(img);

  }

  /* success */

  return TRUE;

}

static GByteArray *

fu_efi_filesystem_write(FuFirmware *firmware, GError **error)

{

  g_autoptr(GByteArray) buf = g_byte_array_new();

  g_autoptr(GPtrArray) images = fu_firmware_get_images(firmware);

  /* sanity check */

  if (fu_firmware_get_alignment(firmware) > FU_FIRMWARE_ALIGNMENT_1M) {

    g_set_error(error,

          FWUPD_ERROR,

          FWUPD_ERROR_INVALID_FILE,

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

          fu_firmware_get_alignment(firmware));

    return NULL;

  }

  /* add each file */

  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_get_alignment(firmware), 0xFF);

    /* sanity check */

    if (buf->len > FU_EFI_FILESYSTEM_SIZE_MAX) {

      g_set_error(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INVALID_FILE,

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

            (guint)buf->len,

            (guint)FU_EFI_FILESYSTEM_SIZE_MAX);

      return NULL;

    }

  }

  /* success */

  return g_steal_pointer(&buf);

}

static void

fu_efi_filesystem_init(FuEfiFilesystem *self)

{

#ifdef HAVE_FUZZER

  /* if fuzzing, artificially limit the number of files to avoid using large amounts of RSS

   * when printing the FuEfiFilesystem XML output */

  fu_firmware_set_images_max(FU_FIRMWARE(self), 50);

#else

  fu_firmware_set_images_max(FU_FIRMWARE(self), FU_EFI_FILESYSTEM_FILES_MAX);

#endif

  fu_firmware_set_alignment(FU_FIRMWARE(self), FU_FIRMWARE_ALIGNMENT_8);

  g_type_ensure(FU_TYPE_EFI_FILE);

}

static void

fu_efi_filesystem_class_init(FuEfiFilesystemClass *klass)

{

  FuFirmwareClass *firmware_class = FU_FIRMWARE_CLASS(klass);

  firmware_class->parse = fu_efi_filesystem_parse;

  firmware_class->write = fu_efi_filesystem_write;

}

/**

 * fu_efi_filesystem_new:

 *

 * Creates a new #FuFirmware

 *

 * Since: 2.0.0

 **/

FuFirmware *

fu_efi_filesystem_new(void)

{

  return FU_FIRMWARE(g_object_new(FU_TYPE_EFI_FILESYSTEM, NULL));

}