/*

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

 *

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

 */

#define G_LOG_DOMAIN "FuEfiVolume"

#include "config.h"

#include "fu-byte-array.h"

#include "fu-common.h"

#include "fu-efi-common.h"

#include "fu-efi-filesystem.h"

#include "fu-efi-struct.h"

#include "fu-efi-volume.h"

#include "fu-input-stream.h"

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

#include "fu-sum.h"

/**

 * FuEfiVolume:

 *

 * A UEFI file volume.

 *

 * See also: [class@FuFirmware]

 */

typedef struct {

  guint16 attrs;

} FuEfiVolumePrivate;

G_DEFINE_TYPE_WITH_PRIVATE(FuEfiVolume, fu_efi_volume, FU_TYPE_FIRMWARE)

#define GET_PRIVATE(o) (fu_efi_volume_get_instance_private(o))

static void

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

{

  FuEfiVolume *self = FU_EFI_VOLUME(firmware);

  FuEfiVolumePrivate *priv = GET_PRIVATE(self);

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

  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)));

  }

}

static gboolean

fu_efi_volume_validate(FuFirmware *firmware, GInputStream *stream, gsize offset, GError **error)

{

  return fu_struct_efi_volume_validate_stream(stream, offset, error);

}

static gboolean

fu_efi_volume_parse(FuFirmware *firmware,

        GInputStream *stream,

        FuFirmwareParseFlags flags,

        GError **error)

{

  FuEfiVolume *self = FU_EFI_VOLUME(firmware);

  FuEfiVolumePrivate *priv = GET_PRIVATE(self);

  gsize blockmap_sz = 0;

  gsize offset = 0;

  gsize streamsz = 0;

  guint16 hdr_length = 0;

  guint32 attrs = 0;

  guint64 fv_length = 0;

  guint8 alignment;

  g_autofree gchar *guid_str = NULL;

  g_autoptr(GByteArray) st_hdr = NULL;

  g_autoptr(GInputStream) partial_stream = NULL;

  /* parse */

  st_hdr = fu_struct_efi_volume_parse_stream(stream, 0x0, error);

  if (st_hdr == NULL)

    return FALSE;

  /* guid */

  guid_str = fwupd_guid_to_string(fu_struct_efi_volume_get_guid(st_hdr),

          FWUPD_GUID_FLAG_MIXED_ENDIAN);

  g_debug("volume GUID: %s [%s]", guid_str, fu_efi_guid_to_name(guid_str));

  /* length */

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

    return FALSE;

  fv_length = fu_struct_efi_volume_get_length(st_hdr);

  if (fv_length == 0x0) {

    g_set_error_literal(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INTERNAL,

            "invalid volume length");

    return FALSE;

  }

  fu_firmware_set_size(firmware, fv_length);

  attrs = fu_struct_efi_volume_get_attrs(st_hdr);

  alignment = (attrs & 0x00ff0000) >> 16;

  if (alignment > FU_FIRMWARE_ALIGNMENT_2G) {

    g_set_error(error,

          FWUPD_ERROR,

          FWUPD_ERROR_NOT_FOUND,

          "0x%x invalid, maximum is 0x%x",

          (guint)alignment,

          (guint)FU_FIRMWARE_ALIGNMENT_2G);

    return FALSE;

  }

  fu_firmware_set_alignment(firmware, alignment);

  priv->attrs = attrs & 0xffff;

  hdr_length = fu_struct_efi_volume_get_hdr_len(st_hdr);

  if (hdr_length < st_hdr->len || hdr_length > fv_length || hdr_length > streamsz ||

      hdr_length % 2 != 0) {

    g_set_error(error,

          FWUPD_ERROR,

          FWUPD_ERROR_INTERNAL,

          "invalid volume header length 0x%x",

          (guint)hdr_length);

    return FALSE;

  }

  /* verify checksum */

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

    guint16 checksum_verify;

    g_autoptr(GBytes) blob_hdr = NULL;

    blob_hdr = fu_input_stream_read_bytes(stream, 0x0, hdr_length, NULL, error);

    if (blob_hdr == NULL)

      return FALSE;

    checksum_verify = fu_sum16w_bytes(blob_hdr, G_LITTLE_ENDIAN);

    if (checksum_verify != 0) {

      g_set_error(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INVALID_FILE,

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

            checksum_verify,

            fu_struct_efi_volume_get_checksum(st_hdr));

      return FALSE;

    }

  }

  /* extended header items */

  if (fu_struct_efi_volume_get_ext_hdr(st_hdr) != 0) {

    g_autoptr(GByteArray) st_ext_hdr = NULL;

    goffset offset_ext = fu_struct_efi_volume_get_ext_hdr(st_hdr);

    st_ext_hdr =

        fu_struct_efi_volume_ext_header_parse_stream(stream, offset_ext, error);

    if (st_ext_hdr == NULL)

      return FALSE;

    offset_ext += fu_struct_efi_volume_ext_header_get_size(st_ext_hdr);

    do {

      g_autoptr(GByteArray) st_ext_entry = NULL;

      st_ext_entry =

          fu_struct_efi_volume_ext_entry_parse_stream(stream, offset_ext, error);

      if (st_ext_entry == NULL)

        return FALSE;

      if (fu_struct_efi_volume_ext_entry_get_size(st_ext_entry) == 0x0) {

        g_set_error_literal(error,

                FWUPD_ERROR,

                FWUPD_ERROR_INVALID_DATA,

                "EFI_VOLUME_EXT_ENTRY invalid size");

        return FALSE;

      }

      if (fu_struct_efi_volume_ext_entry_get_size(st_ext_entry) == 0xFFFF)

        break;

      offset_ext += fu_struct_efi_volume_ext_entry_get_size(st_ext_entry);

    } while ((gsize)offset_ext < fv_length);

  }

  /* add image */

  partial_stream =

      fu_partial_input_stream_new(stream, hdr_length, fv_length - hdr_length, error);

  if (partial_stream == NULL) {

    g_prefix_error(error, "failed to cut EFI volume: ");

    return FALSE;

  }

  fu_firmware_set_id(firmware, guid_str);

  fu_firmware_set_size(firmware, fv_length);

  /* parse, which might cascade and do something like FFS2 */

  if (g_strcmp0(guid_str, FU_EFI_VOLUME_GUID_FFS2) == 0 ||

      g_strcmp0(guid_str, FU_EFI_VOLUME_GUID_FFS3) == 0) {

    g_autoptr(FuFirmware) img = fu_efi_filesystem_new();

    fu_firmware_set_alignment(img, fu_firmware_get_alignment(firmware));

    if (!fu_firmware_parse_stream(img,

                partial_stream,

                0x0,

                flags | FU_FIRMWARE_PARSE_FLAG_NO_SEARCH,

                error))

      return FALSE;

    fu_firmware_add_image(firmware, img);

  } else if (g_strcmp0(guid_str, FU_EFI_VOLUME_GUID_NVRAM_EVSA) == 0 ||

       g_strcmp0(guid_str, FU_EFI_VOLUME_GUID_NVRAM_EVSA2) == 0) {

    g_debug("ignoring %s [%s] EFI FV", guid_str, fu_efi_guid_to_name(guid_str));

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

      return FALSE;

  } else {

    g_warning("no idea how to parse %s [%s] EFI volume",

        guid_str,

        fu_efi_guid_to_name(guid_str));

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

      return FALSE;

  }

  /* skip the blockmap */

  offset += st_hdr->len;

  while (offset < streamsz) {

    guint32 num_blocks;

    guint32 length;

    g_autoptr(GByteArray) st_blk = NULL;

    st_blk = fu_struct_efi_volume_block_map_parse_stream(stream, offset, error);

    if (st_blk == NULL)

      return FALSE;

    num_blocks = fu_struct_efi_volume_block_map_get_num_blocks(st_blk);

    length = fu_struct_efi_volume_block_map_get_length(st_blk);

    offset += st_blk->len;

    if (num_blocks == 0x0 && length == 0x0)

      break;

    blockmap_sz += (gsize)num_blocks * (gsize)length;

  }

  if (blockmap_sz < (gsize)fv_length) {

    g_set_error_literal(error,

            FWUPD_ERROR,

            FWUPD_ERROR_INTERNAL,

            "blocks allocated is less than volume length");

    return FALSE;

  }

  /* success */

  return TRUE;

}

static GByteArray *

fu_efi_volume_write(FuFirmware *firmware, GError **error)

{

  FuEfiVolume *self = FU_EFI_VOLUME(firmware);

  FuEfiVolumePrivate *priv = GET_PRIVATE(self);

  g_autoptr(GByteArray) buf = fu_struct_efi_volume_new();

  g_autoptr(GByteArray) st_blk = fu_struct_efi_volume_block_map_new();

  fwupd_guid_t guid = {0x0};

  guint32 hdr_length = 0x48;

  guint64 fv_length;

  g_autoptr(GBytes) img_blob = NULL;

  g_autoptr(FuFirmware) img = NULL;

  /* 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;

  }

  /* GUID */

  if (fu_firmware_get_id(firmware) == NULL) {

    g_set_error(error, FWUPD_ERROR, FWUPD_ERROR_INTERNAL, "no GUID set for EFI FV");

    return NULL;

  }

  if (!fwupd_guid_from_string(fu_firmware_get_id(firmware),

            &guid,

            FWUPD_GUID_FLAG_MIXED_ENDIAN,

            error))

    return NULL;

  /* length */

  img = fu_firmware_get_image_by_id(firmware, NULL, NULL);

  if (img != NULL) {

    img_blob = fu_firmware_write(img, error);

    if (img_blob == NULL) {

      g_prefix_error(error, "no EFI FV child payload: ");

      return NULL;

    }

  } else {

    img_blob = fu_firmware_get_bytes_with_patches(firmware, error);

    if (img_blob == NULL) {

      g_prefix_error(error, "no EFI FV payload: ");

      return NULL;

    }

  }

  /* pack */

  fu_struct_efi_volume_set_guid(buf, &guid);

  fv_length = fu_common_align_up(hdr_length + g_bytes_get_size(img_blob),

               fu_firmware_get_alignment(firmware));

  fu_struct_efi_volume_set_length(buf, fv_length);

  fu_struct_efi_volume_set_attrs(buf,

               priv->attrs |

             ((guint32)fu_firmware_get_alignment(firmware) << 16));

  fu_struct_efi_volume_set_hdr_len(buf, hdr_length);

  /* blockmap */

  fu_struct_efi_volume_block_map_set_num_blocks(st_blk, fv_length);

  fu_struct_efi_volume_block_map_set_length(st_blk, 0x1);

  g_byte_array_append(buf, st_blk->data, st_blk->len);

  fu_struct_efi_volume_block_map_set_num_blocks(st_blk, 0x0);

  fu_struct_efi_volume_block_map_set_length(st_blk, 0x0);

  g_byte_array_append(buf, st_blk->data, st_blk->len);

  /* fix up checksum */

  fu_struct_efi_volume_set_checksum(buf,

            0x10000 -

                fu_sum16w(buf->data, buf->len, G_LITTLE_ENDIAN));

  /* pad contents to alignment */

  fu_byte_array_append_bytes(buf, img_blob);

  fu_byte_array_set_size(buf, fv_length, 0xFF);

  /* success */

  return g_steal_pointer(&buf);

}

static void

fu_efi_volume_init(FuEfiVolume *self)

{

  FuEfiVolumePrivate *priv = GET_PRIVATE(self);

  priv->attrs = 0xfeff;

  g_type_ensure(FU_TYPE_EFI_FILESYSTEM);

}

static void

fu_efi_volume_class_init(FuEfiVolumeClass *klass)

{

  FuFirmwareClass *firmware_class = FU_FIRMWARE_CLASS(klass);

  firmware_class->validate = fu_efi_volume_validate;

  firmware_class->parse = fu_efi_volume_parse;

  firmware_class->write = fu_efi_volume_write;

  firmware_class->export = fu_efi_volume_export;

}

/**

 * fu_efi_volume_new:

 *

 * Creates a new #FuFirmware

 *

 * Since: 2.0.0

 **/

FuFirmware *

fu_efi_volume_new(void)

{

  return FU_FIRMWARE(g_object_new(FU_TYPE_EFI_VOLUME, NULL));

}