/*

 * File header functions

 *

 * Copyright (C) 2010-2023, Joachim Metz <joachim.metz@gmail.com>

 *

 * Refer to AUTHORS for acknowledgements.

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>.

 */

#include <common.h>

#include <byte_stream.h>

#include <memory.h>

#include <types.h>

#include "libqcow_debug.h"

#include "libqcow_file_header.h"

#include "libqcow_io_handle.h"

#include "libqcow_libcerror.h"

#include "libqcow_libcnotify.h"

#include "qcow_file_header.h"

/* Creates file header

 * Make sure the value file_header is referencing, is set to NULL

 * Returns 1 if successful or -1 on error

 */

int libqcow_file_header_initialize(

     libqcow_file_header_t **file_header,

     libcerror_error_t **error )

{

  static char *function = "libqcow_file_header_initialize";

  if( file_header == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid file header.",

     function );

    return( -1 );

  }

  if( *file_header != NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_VALUE_ALREADY_SET,

     "%s: invalid file header value already set.",

     function );

    return( -1 );

  }

  *file_header = memory_allocate_structure(

                  libqcow_file_header_t );

  if( *file_header == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_MEMORY,

     LIBCERROR_MEMORY_ERROR_INSUFFICIENT,

     "%s: unable to create file header.",

     function );

    goto on_error;

  }

  if( memory_set(

       *file_header,

       0,

       sizeof( libqcow_file_header_t ) ) == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_MEMORY,

     LIBCERROR_MEMORY_ERROR_SET_FAILED,

     "%s: unable to clear file header.",

     function );

    goto on_error;

  }

  return( 1 );

on_error:

  if( *file_header != NULL )

  {

    memory_free(

     *file_header );

    *file_header = NULL;

  }

  return( -1 );

}

/* Frees file header

 * Returns 1 if successful or -1 on error

 */

int libqcow_file_header_free(

     libqcow_file_header_t **file_header,

     libcerror_error_t **error )

{

  static char *function = "libqcow_file_header_free";

  if( file_header == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid file header.",

     function );

    return( -1 );

  }

  if( *file_header != NULL )

  {

    memory_free(

     *file_header );

    *file_header = NULL;

  }

  return( 1 );

}

/* Reads the file header data

 * Returns 1 if successful or -1 on error

 */

int libqcow_file_header_read_data(

     libqcow_file_header_t *file_header,

     const uint8_t *data,

     size_t data_size,

     libcerror_error_t **error )

{

  static char *function               = "libqcow_file_header_read_data";

  size_t file_header_data_size        = 0;

  uint64_t compatible_feature_flags   = 0;

  uint64_t incompatible_feature_flags = 0;

  uint64_t safe_level1_table_offset   = 0;

  uint64_t safe_snapshots_offset      = 0;

  uint64_t supported_feature_flags    = 0;

  uint32_t file_header_size           = 0;

#if defined( HAVE_DEBUG_OUTPUT )

  uint64_t value_64bit                = 0;

  uint32_t value_32bit                = 0;

  uint16_t value_16bit                = 0;

#endif

  if( file_header == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid file header.",

     function );

    return( -1 );

  }

  if( data == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid data.",

     function );

    return( -1 );

  }

  if( ( data_size < 8 )

   || ( data_size > (size_t) SSIZE_MAX ) )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,

     "%s: invalid data size value out of bounds.",

     function );

    return( -1 );

  }

  if( memory_compare(

       ( (qcow_file_header_v1_t *) data )->signature,

       qcow_file_signature,

       4 ) != 0 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_UNSUPPORTED_VALUE,

     "%s: unsupported file signature.",

     function );

    return( -1 );

  }

  byte_stream_copy_to_uint32_big_endian(

   ( (qcow_file_header_v1_t *) data )->format_version,

   file_header->format_version );

  if( file_header->format_version == 1 )

  {

    file_header_data_size = sizeof( qcow_file_header_v1_t );

  }

  else if( file_header->format_version == 2 )

  {

    file_header_data_size = sizeof( qcow_file_header_v2_t );

  }

  else if( file_header->format_version == 3 )

  {

    file_header_data_size = sizeof( qcow_file_header_v3_t );

  }

  else

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_UNSUPPORTED_VALUE,

     "%s: unsupported format version: %" PRIu32 ".",

     function,

     file_header->format_version );

    return( -1 );

  }

  if( data_size < file_header_data_size )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,

     "%s: invalid data size value out of bounds.",

     function );

    return( -1 );

  }

#if defined( HAVE_DEBUG_OUTPUT )

  if( libcnotify_verbose != 0 )

  {

    libcnotify_printf(

     "%s: file header data:\n",

     function );

    libcnotify_print_data(

     data,

     file_header_data_size,

     0 );

  }

#endif

  byte_stream_copy_to_uint64_big_endian(

   ( (qcow_file_header_v1_t *) data )->backing_filename_offset,

   file_header->backing_filename_offset );

  byte_stream_copy_to_uint32_big_endian(

   ( (qcow_file_header_v1_t *) data )->backing_filename_size,

   file_header->backing_filename_size );

#if defined( HAVE_DEBUG_OUTPUT )

  if( libcnotify_verbose != 0 )

  {

    byte_stream_copy_to_uint32_big_endian(

     ( (qcow_file_header_v1_t *) data )->signature,

     value_32bit );

    libcnotify_printf(

     "%s: signature\t\t\t\t: 0x%08" PRIx32 "\n",

     function,

     value_32bit );

    libcnotify_printf(

     "%s: format version\t\t\t\t: %" PRIu32 "\n",

     function,

     file_header->format_version );

    libcnotify_printf(

     "%s: backing filename offset\t\t\t: %" PRIu32 "\n",

     function,

     file_header->backing_filename_offset );

    libcnotify_printf(

     "%s: backing filename size\t\t\t: %" PRIu32 "\n",

     function,

     file_header->backing_filename_size );

  }

#endif /* defined( HAVE_DEBUG_OUTPUT ) */

  if( file_header->format_version == 3 )

  {

    if( data_size < sizeof( qcow_file_header_v3_t ) )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

       LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,

       "%s: invalid data size value out of bounds.",

       function );

      return( -1 );

    }

  }

  if( file_header->format_version == 1 )

  {

    byte_stream_copy_to_uint64_big_endian(

     ( (qcow_file_header_v1_t *) data )->media_size,

     file_header->media_size );

    file_header->number_of_cluster_block_bits = (uint32_t) ( (qcow_file_header_v1_t *) data )->number_of_cluster_block_bits;

    file_header->number_of_level2_table_bits = (uint32_t) ( (qcow_file_header_v1_t *) data )->number_of_level2_table_bits;

    byte_stream_copy_to_uint32_big_endian(

     ( (qcow_file_header_v1_t *) data )->encryption_method,

     file_header->encryption_method );

    byte_stream_copy_to_uint64_big_endian(

     ( (qcow_file_header_v2_t *) data )->level1_table_offset,

     safe_level1_table_offset );

#if defined( HAVE_DEBUG_OUTPUT )

    if( libcnotify_verbose != 0 )

    {

      byte_stream_copy_to_uint32_big_endian(

       ( (qcow_file_header_v1_t *) data )->modification_time,

       value_32bit );

      libcnotify_printf(

       "%s: modification time\t\t\t: %" PRIu32 "\n",

       function,

       value_32bit );

      libcnotify_printf(

       "%s: media size\t\t\t\t: %" PRIu64 "\n",

       function,

       file_header->media_size );

      libcnotify_printf(

       "%s: number of cluster block bits\t\t: %" PRIu32 "\n",

       function,

       file_header->number_of_cluster_block_bits );

      libcnotify_printf(

       "%s: number of level 2 table bits\t\t: %" PRIu32 "\n",

       function,

       file_header->number_of_level2_table_bits );

      byte_stream_copy_to_uint16_big_endian(

       ( (qcow_file_header_v1_t *) data )->unknown1,

       value_16bit );

      libcnotify_printf(

       "%s: unknown1\t\t\t\t\t: 0x%04" PRIx16 "\n",

       function,

       value_16bit );

      libcnotify_printf(

       "%s: encryption method\t\t\t: %" PRIu32 "\n",

       function,

       file_header->encryption_method );

      libcnotify_printf(

       "%s: level 1 table offset\t\t\t: 0x%08" PRIx64 "\n",

       function,

       safe_level1_table_offset );

    }

#endif /* defined( HAVE_DEBUG_OUTPUT ) */

  }

  else if( ( file_header->format_version == 2 )

        || ( file_header->format_version == 3 ) )

  {

    byte_stream_copy_to_uint32_big_endian(

     ( (qcow_file_header_v2_t *) data )->number_of_cluster_block_bits,

     file_header->number_of_cluster_block_bits );

    byte_stream_copy_to_uint32_big_endian(

     ( (qcow_file_header_v2_t *) data )->number_of_level1_table_references,

     file_header->number_of_level1_table_references );

    byte_stream_copy_to_uint64_big_endian(

     ( (qcow_file_header_v2_t *) data )->level1_table_offset,

     safe_level1_table_offset );

    byte_stream_copy_to_uint64_big_endian(

     ( (qcow_file_header_v2_t *) data )->media_size,

     file_header->media_size );

    byte_stream_copy_to_uint32_big_endian(

     ( (qcow_file_header_v2_t *) data )->encryption_method,

     file_header->encryption_method );

    byte_stream_copy_to_uint32_big_endian(

     ( (qcow_file_header_v2_t *) data )->number_of_snapshots,

     file_header->number_of_snapshots );

    byte_stream_copy_to_uint64_big_endian(

     ( (qcow_file_header_v2_t *) data )->snapshots_offset,

     safe_snapshots_offset );

#if defined( HAVE_DEBUG_OUTPUT )

    if( libcnotify_verbose != 0 )

    {

      libcnotify_printf(

       "%s: number of cluster block bits\t\t: %" PRIu32 "\n",

       function,

       file_header->number_of_cluster_block_bits );

      libcnotify_printf(

       "%s: media size\t\t\t\t: %" PRIu64 "\n",

       function,

       file_header->media_size );

      libcnotify_printf(

       "%s: encryption method\t\t\t: %" PRIu32 "\n",

       function,

       file_header->encryption_method );

      libcnotify_printf(

       "%s: number of level 1 table references\t: %" PRIu32 "\n",

       function,

       file_header->number_of_level1_table_references );

      libcnotify_printf(

       "%s: level 1 table offset\t\t\t: 0x%08" PRIx64 "\n",

       function,

       safe_level1_table_offset );

      byte_stream_copy_to_uint64_big_endian(

       ( (qcow_file_header_v2_t *) data )->reference_count_table_offset,

       value_64bit );

      libcnotify_printf(

       "%s: reference count table offset\t\t: 0x%08" PRIx64 "\n",

       function,

       value_64bit );

      byte_stream_copy_to_uint32_big_endian(

       ( (qcow_file_header_v2_t *) data )->reference_count_table_clusters,

       value_32bit );

      libcnotify_printf(

       "%s: reference count table clusters\t\t: %" PRIu32 "\n",

       function,

       value_32bit );

      libcnotify_printf(

       "%s: number of snapshots\t\t\t: %" PRIu32 "\n",

       function,

       file_header->number_of_snapshots );

      libcnotify_printf(

       "%s: snapshots offset\t\t\t\t: 0x%08" PRIx64 "\n",

       function,

       safe_snapshots_offset );

    }

#endif /* defined( HAVE_DEBUG_OUTPUT ) */

  }

  if( safe_level1_table_offset > (uint64_t) INT64_MAX )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_RUNTIME,

     LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,

     "%s: invalid level1 table offset value out of bounds.",

     function );

    return( -1 );

  }

  if( file_header->format_version == 3 )

  {

    byte_stream_copy_to_uint64_big_endian(

     ( (qcow_file_header_v3_t *) data )->incompatible_feature_flags,

     incompatible_feature_flags );

    byte_stream_copy_to_uint64_big_endian(

     ( (qcow_file_header_v3_t *) data )->compatible_feature_flags,

     compatible_feature_flags );

    byte_stream_copy_to_uint32_big_endian(

     ( (qcow_file_header_v3_t *) data )->header_size,

     file_header_size );

#if defined( HAVE_DEBUG_OUTPUT )

    if( libcnotify_verbose != 0 )

    {

      libcnotify_printf(

       "%s: incompatible feature flags\t\t: 0x%08" PRIx64 "\n",

       function,

       incompatible_feature_flags );

      libcnotify_printf(

       "%s: compatible feature flags\t\t\t: 0x%08" PRIx64 "\n",

       function,

       compatible_feature_flags );

      byte_stream_copy_to_uint64_big_endian(

       ( (qcow_file_header_v3_t *) data )->auto_clear_feature_flags,

       value_64bit );

      libcnotify_printf(

       "%s: auto-clear feature flags\t\t\t: 0x%08" PRIx64 "\n",

       function,

       value_64bit );

      byte_stream_copy_to_uint32_big_endian(

       ( (qcow_file_header_v3_t *) data )->reference_count_order,

       value_32bit );

      libcnotify_printf(

       "%s: reference count order\t\t\t: %" PRIu32 "\n",

       function,

       value_32bit );

      libcnotify_printf(

       "%s: file header size\t\t\t\t: %" PRIu32 "\n",

       function,

       file_header_size );

      if( file_header_size >= 104 )

      {

        libcnotify_printf(

         "%s: compression type\t\t\t\t: %" PRIu8 "\n",

         function,

         ( (qcow_file_header_v3_t *) data )->compression_type );

        libcnotify_printf(

         "%s: unknown1:\n",

         function );

        libcnotify_print_data(

         ( (qcow_file_header_v3_t *) data )->unknown1,

         7,

         0 );

      }

    }

#endif /* defined( HAVE_DEBUG_OUTPUT ) */

    supported_feature_flags = 0x00000001UL;

    if( ( incompatible_feature_flags & ~( supported_feature_flags ) ) != 0 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_RUNTIME,

       LIBCERROR_RUNTIME_ERROR_UNSUPPORTED_VALUE,

       "%s: unsupported incompatible features flags: 0x%08" PRIx64 ".",

       function,

       incompatible_feature_flags );

      return( -1 );

    }

    supported_feature_flags = 0x00000001UL;

    if( ( compatible_feature_flags & ~( supported_feature_flags ) ) != 0 )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_RUNTIME,

       LIBCERROR_RUNTIME_ERROR_UNSUPPORTED_VALUE,

       "%s: unsupported compatible features flags: 0x%08" PRIx64 ".",

       function,

       compatible_feature_flags );

      return( -1 );

    }

    if( ( file_header_size != 104 )

     && ( file_header_size != 112 ) )

    {

      libcerror_error_set(

       error,

       LIBCERROR_ERROR_DOMAIN_RUNTIME,

       LIBCERROR_RUNTIME_ERROR_UNSUPPORTED_VALUE,

       "%s: unsupported file header size: %d.",

       function,

       file_header_size );

      return( -1 );

    }

  }

#if defined( HAVE_DEBUG_OUTPUT )

  if( libcnotify_verbose != 0 )

  {

    if( ( file_header->format_version != 3 )

     || ( file_header_size <= 104 ) )

    {

      libcnotify_printf(

       "\n" );

    }

  }

#endif

  file_header->level1_table_offset = (off64_t) safe_level1_table_offset;

  file_header->snapshots_offset    = (off64_t) safe_snapshots_offset;

  return( 1 );

}

/* Reads the file header

 * Returns 1 if successful or -1 on error

 */

int libqcow_file_header_read_file_io_handle(

     libqcow_file_header_t *file_header,

     libbfio_handle_t *file_io_handle,

     libcerror_error_t **error )

{

  uint8_t file_header_data[ 512 ];

  static char *function = "libqcow_file_header_read_file_io_handle";

  ssize_t read_count    = 0;

  if( file_header == NULL )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,

     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,

     "%s: invalid file header.",

     function );

    return( -1 );

  }

#if defined( HAVE_DEBUG_OUTPUT )

  if( libcnotify_verbose != 0 )

  {

    libcnotify_printf(

     "%s: reading file header at offset: 0 (0x00000000)\n",

     function );

  }

#endif

  read_count = libbfio_handle_read_buffer_at_offset(

                file_io_handle,

                file_header_data,

                512,

                0,

                error );

  if( read_count != (ssize_t) 512 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_IO,

     LIBCERROR_IO_ERROR_READ_FAILED,

     "%s: unable to read file header data at offset: 0 (0x00000000).",

     function );

    return( -1 );

  }

  if( libqcow_file_header_read_data(

       file_header,

       file_header_data,

       512,

       error ) != 1 )

  {

    libcerror_error_set(

     error,

     LIBCERROR_ERROR_DOMAIN_IO,

     LIBCERROR_IO_ERROR_READ_FAILED,

     "%s: unable to read file header.",

     function );

    return( -1 );

  }

  return( 1 );

}