| /**************************************************************************** |
| * |
| * otvmath.c |
| * |
| * OpenType MATH table validation (body). |
| * |
| * Copyright (C) 2007-2020 by |
| * David Turner, Robert Wilhelm, and Werner Lemberg. |
| * |
| * Written by George Williams. |
| * |
| * 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. |
| * |
| */ |
| |
| |
| #include "otvalid.h" |
| #include "otvcommn.h" |
| #include "otvgpos.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 otvmath |
| |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** MATH TYPOGRAPHIC CONSTANTS *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| static void |
| otv_MathConstants_validate( FT_Bytes table, |
| OTV_Validator otvalid ) |
| { |
| FT_Bytes p = table; |
| FT_UInt i; |
| FT_UInt table_size; |
| |
| OTV_OPTIONAL_TABLE( DeviceTableOffset ); |
| |
| |
| OTV_NAME_ENTER( "MathConstants" ); |
| |
| /* 56 constants, 51 have device tables */ |
| OTV_LIMIT_CHECK( 2 * ( 56 + 51 ) ); |
| table_size = 2 * ( 56 + 51 ); |
| |
| p += 4 * 2; /* First 4 constants have no device tables */ |
| for ( i = 0; i < 51; i++ ) |
| { |
| p += 2; /* skip the value */ |
| OTV_OPTIONAL_OFFSET( DeviceTableOffset ); |
| OTV_SIZE_CHECK( DeviceTableOffset ); |
| if ( DeviceTableOffset ) |
| otv_Device_validate( table + DeviceTableOffset, otvalid ); |
| } |
| |
| OTV_EXIT; |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** MATH ITALICS CORRECTION *****/ |
| /***** MATH TOP ACCENT ATTACHMENT *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| static void |
| otv_MathItalicsCorrectionInfo_validate( FT_Bytes table, |
| OTV_Validator otvalid, |
| FT_Int isItalic ) |
| { |
| FT_Bytes p = table; |
| FT_UInt i, cnt, table_size; |
| |
| OTV_OPTIONAL_TABLE( Coverage ); |
| OTV_OPTIONAL_TABLE( DeviceTableOffset ); |
| |
| FT_UNUSED( isItalic ); /* only used if tracing is active */ |
| |
| |
| OTV_NAME_ENTER( isItalic ? "MathItalicsCorrectionInfo" |
| : "MathTopAccentAttachment" ); |
| |
| OTV_LIMIT_CHECK( 4 ); |
| |
| OTV_OPTIONAL_OFFSET( Coverage ); |
| cnt = FT_NEXT_USHORT( p ); |
| |
| OTV_LIMIT_CHECK( 4 * cnt ); |
| table_size = 4 + 4 * cnt; |
| |
| OTV_SIZE_CHECK( Coverage ); |
| otv_Coverage_validate( table + Coverage, otvalid, (FT_Int)cnt ); |
| |
| for ( i = 0; i < cnt; i++ ) |
| { |
| p += 2; /* Skip the value */ |
| OTV_OPTIONAL_OFFSET( DeviceTableOffset ); |
| OTV_SIZE_CHECK( DeviceTableOffset ); |
| if ( DeviceTableOffset ) |
| otv_Device_validate( table + DeviceTableOffset, otvalid ); |
| } |
| |
| OTV_EXIT; |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** MATH KERNING *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| static void |
| otv_MathKern_validate( FT_Bytes table, |
| OTV_Validator otvalid ) |
| { |
| FT_Bytes p = table; |
| FT_UInt i, cnt, table_size; |
| |
| OTV_OPTIONAL_TABLE( DeviceTableOffset ); |
| |
| |
| /* OTV_NAME_ENTER( "MathKern" );*/ |
| |
| OTV_LIMIT_CHECK( 2 ); |
| |
| cnt = FT_NEXT_USHORT( p ); |
| |
| OTV_LIMIT_CHECK( 4 * cnt + 2 ); |
| table_size = 4 + 4 * cnt; |
| |
| /* Heights */ |
| for ( i = 0; i < cnt; i++ ) |
| { |
| p += 2; /* Skip the value */ |
| OTV_OPTIONAL_OFFSET( DeviceTableOffset ); |
| OTV_SIZE_CHECK( DeviceTableOffset ); |
| if ( DeviceTableOffset ) |
| otv_Device_validate( table + DeviceTableOffset, otvalid ); |
| } |
| |
| /* One more Kerning value */ |
| for ( i = 0; i < cnt + 1; i++ ) |
| { |
| p += 2; /* Skip the value */ |
| OTV_OPTIONAL_OFFSET( DeviceTableOffset ); |
| OTV_SIZE_CHECK( DeviceTableOffset ); |
| if ( DeviceTableOffset ) |
| otv_Device_validate( table + DeviceTableOffset, otvalid ); |
| } |
| |
| OTV_EXIT; |
| } |
| |
| |
| static void |
| otv_MathKernInfo_validate( FT_Bytes table, |
| OTV_Validator otvalid ) |
| { |
| FT_Bytes p = table; |
| FT_UInt i, j, cnt, table_size; |
| |
| OTV_OPTIONAL_TABLE( Coverage ); |
| OTV_OPTIONAL_TABLE( MKRecordOffset ); |
| |
| |
| OTV_NAME_ENTER( "MathKernInfo" ); |
| |
| OTV_LIMIT_CHECK( 4 ); |
| |
| OTV_OPTIONAL_OFFSET( Coverage ); |
| cnt = FT_NEXT_USHORT( p ); |
| |
| OTV_LIMIT_CHECK( 8 * cnt ); |
| table_size = 4 + 8 * cnt; |
| |
| OTV_SIZE_CHECK( Coverage ); |
| otv_Coverage_validate( table + Coverage, otvalid, (FT_Int)cnt ); |
| |
| for ( i = 0; i < cnt; i++ ) |
| { |
| for ( j = 0; j < 4; j++ ) |
| { |
| OTV_OPTIONAL_OFFSET( MKRecordOffset ); |
| OTV_SIZE_CHECK( MKRecordOffset ); |
| if ( MKRecordOffset ) |
| otv_MathKern_validate( table + MKRecordOffset, otvalid ); |
| } |
| } |
| |
| OTV_EXIT; |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** MATH GLYPH INFO *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| static void |
| otv_MathGlyphInfo_validate( FT_Bytes table, |
| OTV_Validator otvalid ) |
| { |
| FT_Bytes p = table; |
| FT_UInt MathItalicsCorrectionInfo, MathTopAccentAttachment; |
| FT_UInt ExtendedShapeCoverage, MathKernInfo; |
| |
| |
| OTV_NAME_ENTER( "MathGlyphInfo" ); |
| |
| OTV_LIMIT_CHECK( 8 ); |
| |
| MathItalicsCorrectionInfo = FT_NEXT_USHORT( p ); |
| MathTopAccentAttachment = FT_NEXT_USHORT( p ); |
| ExtendedShapeCoverage = FT_NEXT_USHORT( p ); |
| MathKernInfo = FT_NEXT_USHORT( p ); |
| |
| if ( MathItalicsCorrectionInfo ) |
| otv_MathItalicsCorrectionInfo_validate( |
| table + MathItalicsCorrectionInfo, otvalid, TRUE ); |
| |
| /* Italic correction and Top Accent Attachment have the same format */ |
| if ( MathTopAccentAttachment ) |
| otv_MathItalicsCorrectionInfo_validate( |
| table + MathTopAccentAttachment, otvalid, FALSE ); |
| |
| if ( ExtendedShapeCoverage ) |
| { |
| OTV_NAME_ENTER( "ExtendedShapeCoverage" ); |
| otv_Coverage_validate( table + ExtendedShapeCoverage, otvalid, -1 ); |
| OTV_EXIT; |
| } |
| |
| if ( MathKernInfo ) |
| otv_MathKernInfo_validate( table + MathKernInfo, otvalid ); |
| |
| OTV_EXIT; |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** MATH GLYPH CONSTRUCTION *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| static void |
| otv_GlyphAssembly_validate( FT_Bytes table, |
| OTV_Validator otvalid ) |
| { |
| FT_Bytes p = table; |
| FT_UInt pcnt, table_size; |
| FT_UInt i; |
| |
| OTV_OPTIONAL_TABLE( DeviceTableOffset ); |
| |
| |
| /* OTV_NAME_ENTER( "GlyphAssembly" ); */ |
| |
| OTV_LIMIT_CHECK( 6 ); |
| |
| p += 2; /* Skip the Italics Correction value */ |
| OTV_OPTIONAL_OFFSET( DeviceTableOffset ); |
| pcnt = FT_NEXT_USHORT( p ); |
| |
| OTV_LIMIT_CHECK( 8 * pcnt ); |
| table_size = 6 + 8 * pcnt; |
| |
| OTV_SIZE_CHECK( DeviceTableOffset ); |
| if ( DeviceTableOffset ) |
| otv_Device_validate( table + DeviceTableOffset, otvalid ); |
| |
| for ( i = 0; i < pcnt; i++ ) |
| { |
| FT_UInt gid; |
| |
| |
| gid = FT_NEXT_USHORT( p ); |
| if ( gid >= otvalid->glyph_count ) |
| FT_INVALID_GLYPH_ID; |
| p += 2*4; /* skip the Start, End, Full, and Flags fields */ |
| } |
| |
| /* OTV_EXIT; */ |
| } |
| |
| |
| static void |
| otv_MathGlyphConstruction_validate( FT_Bytes table, |
| OTV_Validator otvalid ) |
| { |
| FT_Bytes p = table; |
| FT_UInt vcnt, table_size; |
| FT_UInt i; |
| |
| OTV_OPTIONAL_TABLE( GlyphAssembly ); |
| |
| |
| /* OTV_NAME_ENTER( "MathGlyphConstruction" ); */ |
| |
| OTV_LIMIT_CHECK( 4 ); |
| |
| OTV_OPTIONAL_OFFSET( GlyphAssembly ); |
| vcnt = FT_NEXT_USHORT( p ); |
| |
| OTV_LIMIT_CHECK( 4 * vcnt ); |
| table_size = 4 + 4 * vcnt; |
| |
| for ( i = 0; i < vcnt; i++ ) |
| { |
| FT_UInt gid; |
| |
| |
| gid = FT_NEXT_USHORT( p ); |
| if ( gid >= otvalid->glyph_count ) |
| FT_INVALID_GLYPH_ID; |
| p += 2; /* skip the size */ |
| } |
| |
| OTV_SIZE_CHECK( GlyphAssembly ); |
| if ( GlyphAssembly ) |
| otv_GlyphAssembly_validate( table+GlyphAssembly, otvalid ); |
| |
| /* OTV_EXIT; */ |
| } |
| |
| |
| static void |
| otv_MathVariants_validate( FT_Bytes table, |
| OTV_Validator otvalid ) |
| { |
| FT_Bytes p = table; |
| FT_UInt vcnt, hcnt, i, table_size; |
| |
| OTV_OPTIONAL_TABLE( VCoverage ); |
| OTV_OPTIONAL_TABLE( HCoverage ); |
| OTV_OPTIONAL_TABLE( Offset ); |
| |
| |
| OTV_NAME_ENTER( "MathVariants" ); |
| |
| OTV_LIMIT_CHECK( 10 ); |
| |
| p += 2; /* Skip the MinConnectorOverlap constant */ |
| OTV_OPTIONAL_OFFSET( VCoverage ); |
| OTV_OPTIONAL_OFFSET( HCoverage ); |
| vcnt = FT_NEXT_USHORT( p ); |
| hcnt = FT_NEXT_USHORT( p ); |
| |
| OTV_LIMIT_CHECK( 2 * vcnt + 2 * hcnt ); |
| table_size = 10 + 2 * vcnt + 2 * hcnt; |
| |
| OTV_SIZE_CHECK( VCoverage ); |
| if ( VCoverage ) |
| otv_Coverage_validate( table + VCoverage, otvalid, (FT_Int)vcnt ); |
| |
| OTV_SIZE_CHECK( HCoverage ); |
| if ( HCoverage ) |
| otv_Coverage_validate( table + HCoverage, otvalid, (FT_Int)hcnt ); |
| |
| for ( i = 0; i < vcnt; i++ ) |
| { |
| OTV_OPTIONAL_OFFSET( Offset ); |
| OTV_SIZE_CHECK( Offset ); |
| otv_MathGlyphConstruction_validate( table + Offset, otvalid ); |
| } |
| |
| for ( i = 0; i < hcnt; i++ ) |
| { |
| OTV_OPTIONAL_OFFSET( Offset ); |
| OTV_SIZE_CHECK( Offset ); |
| otv_MathGlyphConstruction_validate( table + Offset, otvalid ); |
| } |
| |
| OTV_EXIT; |
| } |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /***** *****/ |
| /***** MATH TABLE *****/ |
| /***** *****/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| /* sets otvalid->glyph_count */ |
| |
| FT_LOCAL_DEF( void ) |
| otv_MATH_validate( FT_Bytes table, |
| FT_UInt glyph_count, |
| FT_Validator ftvalid ) |
| { |
| OTV_ValidatorRec otvalidrec; |
| OTV_Validator otvalid = &otvalidrec; |
| FT_Bytes p = table; |
| FT_UInt MathConstants, MathGlyphInfo, MathVariants; |
| |
| |
| otvalid->root = ftvalid; |
| |
| FT_TRACE3(( "validating MATH table\n" )); |
| OTV_INIT; |
| |
| OTV_LIMIT_CHECK( 10 ); |
| |
| if ( FT_NEXT_ULONG( p ) != 0x10000UL ) /* Version */ |
| FT_INVALID_FORMAT; |
| |
| MathConstants = FT_NEXT_USHORT( p ); |
| MathGlyphInfo = FT_NEXT_USHORT( p ); |
| MathVariants = FT_NEXT_USHORT( p ); |
| |
| otvalid->glyph_count = glyph_count; |
| |
| otv_MathConstants_validate( table + MathConstants, |
| otvalid ); |
| otv_MathGlyphInfo_validate( table + MathGlyphInfo, |
| otvalid ); |
| otv_MathVariants_validate ( table + MathVariants, |
| otvalid ); |
| |
| FT_TRACE4(( "\n" )); |
| } |
| |
| |
| /* END */ |
