ref: 28c2d7f31c0758e69dded02acfa32af080774e91
dir: /src/gxvalid/gxvfeat.c/
/****************************************************************************
*
* gxvfeat.c
*
* TrueTypeGX/AAT feat table validation (body).
*
* Copyright (C) 2004-2021 by
* suzuki toshiya, Masatake YAMATO, Red Hat K.K.,
* David Turner, Robert Wilhelm, and Werner Lemberg.
*
* This file is part of the FreeType project, and may only be used,
* modified, and distributed under the terms of the FreeType project
* license, LICENSE.TXT. By continuing to use, modify, or distribute
* this file you indicate that you have read the license and
* understand and accept it fully.
*
*/
/****************************************************************************
*
* gxvalid is derived from both gxlayout module and otvalid module.
* Development of gxlayout is supported by the Information-technology
* Promotion Agency(IPA), Japan.
*
*/
#include "gxvalid.h"
#include "gxvcommn.h"
#include "gxvfeat.h"
/**************************************************************************
*
* The macro FT_COMPONENT is used in trace mode. It is an implicit
* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
* messages during execution.
*/
#undef FT_COMPONENT
#define FT_COMPONENT gxvfeat
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** Data and Types *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
typedef struct GXV_feat_DataRec_
{
FT_UInt reserved_size;
FT_UShort feature;
FT_UShort setting;
} GXV_feat_DataRec, *GXV_feat_Data;
#define GXV_FEAT_DATA( field ) GXV_TABLE_DATA( feat, field )
typedef enum GXV_FeatureFlagsMask_
{
GXV_FEAT_MASK_EXCLUSIVE_SETTINGS = 0x8000U,
GXV_FEAT_MASK_DYNAMIC_DEFAULT = 0x4000,
GXV_FEAT_MASK_UNUSED = 0x3F00,
GXV_FEAT_MASK_DEFAULT_SETTING = 0x00FF
} GXV_FeatureFlagsMask;
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** UTILITY FUNCTIONS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
static void
gxv_feat_registry_validate( FT_UShort feature,
FT_UShort nSettings,
FT_Bool exclusive,
GXV_Validator gxvalid )
{
GXV_NAME_ENTER( "feature in registry" );
GXV_TRACE(( " (feature = %u)\n", feature ));
if ( feature >= gxv_feat_registry_length )
{
GXV_TRACE(( "feature number %d is out of range %d\n",
feature, gxv_feat_registry_length ));
GXV_SET_ERR_IF_PARANOID( FT_INVALID_DATA );
goto Exit;
}
if ( gxv_feat_registry[feature].existence == 0 )
{
GXV_TRACE(( "feature number %d is in defined range but doesn't exist\n",
feature ));
GXV_SET_ERR_IF_PARANOID( FT_INVALID_DATA );
goto Exit;
}
if ( gxv_feat_registry[feature].apple_reserved )
{
/* Don't use here. Apple is reserved. */
GXV_TRACE(( "feature number %d is reserved by Apple\n", feature ));
if ( gxvalid->root->level >= FT_VALIDATE_TIGHT )
FT_INVALID_DATA;
}
if ( nSettings != gxv_feat_registry[feature].nSettings )
{
GXV_TRACE(( "feature %d: nSettings %d != defined nSettings %d\n",
feature, nSettings,
gxv_feat_registry[feature].nSettings ));
if ( gxvalid->root->level >= FT_VALIDATE_TIGHT )
FT_INVALID_DATA;
}
if ( exclusive != gxv_feat_registry[feature].exclusive )
{
GXV_TRACE(( "exclusive flag %d differs from predefined value\n",
exclusive ));
if ( gxvalid->root->level >= FT_VALIDATE_TIGHT )
FT_INVALID_DATA;
}
Exit:
GXV_EXIT;
}
static void
gxv_feat_name_index_validate( FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
FT_Bytes p = table;
FT_Short nameIndex;
GXV_NAME_ENTER( "nameIndex" );
GXV_LIMIT_CHECK( 2 );
nameIndex = FT_NEXT_SHORT ( p );
GXV_TRACE(( " (nameIndex = %d)\n", nameIndex ));
gxv_sfntName_validate( (FT_UShort)nameIndex,
255,
32768U,
gxvalid );
GXV_EXIT;
}
static void
gxv_feat_setting_validate( FT_Bytes table,
FT_Bytes limit,
FT_Bool exclusive,
GXV_Validator gxvalid )
{
FT_Bytes p = table;
FT_UShort setting;
GXV_NAME_ENTER( "setting" );
GXV_LIMIT_CHECK( 2 );
setting = FT_NEXT_USHORT( p );
/* If we have exclusive setting, the setting should be odd. */
if ( exclusive && ( setting & 1 ) == 0 )
FT_INVALID_DATA;
gxv_feat_name_index_validate( p, limit, gxvalid );
GXV_FEAT_DATA( setting ) = setting;
GXV_EXIT;
}
static void
gxv_feat_name_validate( FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
FT_Bytes p = table;
FT_UInt reserved_size = GXV_FEAT_DATA( reserved_size );
FT_UShort feature;
FT_UShort nSettings;
FT_ULong settingTable;
FT_UShort featureFlags;
FT_Bool exclusive;
FT_Int last_setting;
FT_UInt i;
GXV_NAME_ENTER( "name" );
/* feature + nSettings + settingTable + featureFlags */
GXV_LIMIT_CHECK( 2 + 2 + 4 + 2 );
feature = FT_NEXT_USHORT( p );
GXV_FEAT_DATA( feature ) = feature;
nSettings = FT_NEXT_USHORT( p );
settingTable = FT_NEXT_ULONG ( p );
featureFlags = FT_NEXT_USHORT( p );
if ( settingTable < reserved_size )
FT_INVALID_OFFSET;
if ( ( featureFlags & GXV_FEAT_MASK_UNUSED ) == 0 )
GXV_SET_ERR_IF_PARANOID( FT_INVALID_DATA );
exclusive = FT_BOOL( featureFlags & GXV_FEAT_MASK_EXCLUSIVE_SETTINGS );
if ( exclusive )
{
FT_Byte dynamic_default;
if ( featureFlags & GXV_FEAT_MASK_DYNAMIC_DEFAULT )
dynamic_default = (FT_Byte)( featureFlags &
GXV_FEAT_MASK_DEFAULT_SETTING );
else
dynamic_default = 0;
/* If exclusive, check whether default setting is in the range. */
if ( !( dynamic_default < nSettings ) )
FT_INVALID_FORMAT;
}
gxv_feat_registry_validate( feature, nSettings, exclusive, gxvalid );
gxv_feat_name_index_validate( p, limit, gxvalid );
p = gxvalid->root->base + settingTable;
for ( last_setting = -1, i = 0; i < nSettings; i++ )
{
gxv_feat_setting_validate( p, limit, exclusive, gxvalid );
if ( (FT_Int)GXV_FEAT_DATA( setting ) <= last_setting )
GXV_SET_ERR_IF_PARANOID( FT_INVALID_FORMAT );
last_setting = (FT_Int)GXV_FEAT_DATA( setting );
/* setting + nameIndex */
p += ( 2 + 2 );
}
GXV_EXIT;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** feat TABLE *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
FT_LOCAL_DEF( void )
gxv_feat_validate( FT_Bytes table,
FT_Face face,
FT_Validator ftvalid )
{
GXV_ValidatorRec gxvalidrec;
GXV_Validator gxvalid = &gxvalidrec;
GXV_feat_DataRec featrec;
GXV_feat_Data feat = &featrec;
FT_Bytes p = table;
FT_Bytes limit = 0;
FT_UInt featureNameCount;
FT_UInt i;
FT_Int last_feature;
gxvalid->root = ftvalid;
gxvalid->table_data = feat;
gxvalid->face = face;
FT_TRACE3(( "validating `feat' table\n" ));
GXV_INIT;
feat->reserved_size = 0;
/* version + featureNameCount + none_0 + none_1 */
GXV_LIMIT_CHECK( 4 + 2 + 2 + 4 );
feat->reserved_size += 4 + 2 + 2 + 4;
if ( FT_NEXT_ULONG( p ) != 0x00010000UL ) /* Version */
FT_INVALID_FORMAT;
featureNameCount = FT_NEXT_USHORT( p );
GXV_TRACE(( " (featureNameCount = %d)\n", featureNameCount ));
if ( !( IS_PARANOID_VALIDATION ) )
p += 6; /* skip (none) and (none) */
else
{
if ( FT_NEXT_USHORT( p ) != 0 )
FT_INVALID_DATA;
if ( FT_NEXT_ULONG( p ) != 0 )
FT_INVALID_DATA;
}
feat->reserved_size += featureNameCount * ( 2 + 2 + 4 + 2 + 2 );
for ( last_feature = -1, i = 0; i < featureNameCount; i++ )
{
gxv_feat_name_validate( p, limit, gxvalid );
if ( (FT_Int)GXV_FEAT_DATA( feature ) <= last_feature )
GXV_SET_ERR_IF_PARANOID( FT_INVALID_FORMAT );
last_feature = GXV_FEAT_DATA( feature );
p += 2 + 2 + 4 + 2 + 2;
}
FT_TRACE4(( "\n" ));
}
/* END */