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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /modules/freetype2/src/otvalid/otvgsub.c | |
parent | Initial commit. (diff) | |
download | firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'modules/freetype2/src/otvalid/otvgsub.c')
-rw-r--r-- | modules/freetype2/src/otvalid/otvgsub.c | 627 |
1 files changed, 627 insertions, 0 deletions
diff --git a/modules/freetype2/src/otvalid/otvgsub.c b/modules/freetype2/src/otvalid/otvgsub.c new file mode 100644 index 0000000000..5d40d9243d --- /dev/null +++ b/modules/freetype2/src/otvalid/otvgsub.c @@ -0,0 +1,627 @@ +/**************************************************************************** + * + * otvgsub.c + * + * OpenType GSUB table validation (body). + * + * Copyright (C) 2004-2023 by + * 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. + * + */ + + +#include "otvalid.h" +#include "otvcommn.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 otvgsub + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB LOOKUP TYPE 1 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* uses otvalid->glyph_count */ + + static void + otv_SingleSubst_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table; + FT_UInt SubstFormat; + + + OTV_NAME_ENTER( "SingleSubst" ); + + OTV_LIMIT_CHECK( 2 ); + SubstFormat = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (format %d)\n", SubstFormat )); + + switch ( SubstFormat ) + { + case 1: /* SingleSubstFormat1 */ + { + FT_Bytes Coverage; + FT_Int DeltaGlyphID; + FT_UInt first_cov, last_cov; + FT_UInt first_idx, last_idx; + + + OTV_LIMIT_CHECK( 4 ); + Coverage = table + FT_NEXT_USHORT( p ); + DeltaGlyphID = FT_NEXT_SHORT( p ); + + otv_Coverage_validate( Coverage, otvalid, -1 ); + + first_cov = otv_Coverage_get_first( Coverage ); + last_cov = otv_Coverage_get_last( Coverage ); + + /* These additions are modulo 65536. */ + first_idx = (FT_UInt)( (FT_Int)first_cov + DeltaGlyphID ) & 0xFFFFU; + last_idx = (FT_UInt)( (FT_Int)last_cov + DeltaGlyphID ) & 0xFFFFU; + + /* Since the maximum number of glyphs is 2^16 - 1 = 65535, */ + /* the largest possible glyph index is 65534. For this */ + /* reason there can't be a wrap-around region, which would */ + /* imply the use of the invalid glyph index 65535. */ + if ( first_idx > last_idx ) + FT_INVALID_DATA; + + if ( last_idx >= otvalid->glyph_count ) + FT_INVALID_DATA; + } + break; + + case 2: /* SingleSubstFormat2 */ + { + FT_UInt Coverage, GlyphCount; + + + OTV_LIMIT_CHECK( 4 ); + Coverage = FT_NEXT_USHORT( p ); + GlyphCount = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount )); + + otv_Coverage_validate( table + Coverage, + otvalid, + (FT_Int)GlyphCount ); + + OTV_LIMIT_CHECK( GlyphCount * 2 ); + + /* Substitute */ + for ( ; GlyphCount > 0; GlyphCount-- ) + if ( FT_NEXT_USHORT( p ) >= otvalid->glyph_count ) + FT_INVALID_GLYPH_ID; + } + break; + + default: + FT_INVALID_FORMAT; + } + + OTV_EXIT; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB LOOKUP TYPE 2 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* sets otvalid->extra1 (glyph count) */ + + static void + otv_MultipleSubst_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table; + FT_UInt SubstFormat; + + + OTV_NAME_ENTER( "MultipleSubst" ); + + OTV_LIMIT_CHECK( 2 ); + SubstFormat = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (format %d)\n", SubstFormat )); + + switch ( SubstFormat ) + { + case 1: + otvalid->extra1 = otvalid->glyph_count; + OTV_NEST2( MultipleSubstFormat1, Sequence ); + OTV_RUN( table, otvalid ); + break; + + default: + FT_INVALID_FORMAT; + } + + OTV_EXIT; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB LOOKUP TYPE 3 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* sets otvalid->extra1 (glyph count) */ + + static void + otv_AlternateSubst_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table; + FT_UInt SubstFormat; + + + OTV_NAME_ENTER( "AlternateSubst" ); + + OTV_LIMIT_CHECK( 2 ); + SubstFormat = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (format %d)\n", SubstFormat )); + + switch ( SubstFormat ) + { + case 1: + otvalid->extra1 = otvalid->glyph_count; + OTV_NEST2( AlternateSubstFormat1, AlternateSet ); + OTV_RUN( table, otvalid ); + break; + + default: + FT_INVALID_FORMAT; + } + + OTV_EXIT; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB LOOKUP TYPE 4 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + +#define LigatureFunc otv_Ligature_validate + + /* uses otvalid->glyph_count */ + + static void + otv_Ligature_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table; + FT_UInt LigatureGlyph, CompCount; + + + OTV_ENTER; + + OTV_LIMIT_CHECK( 4 ); + LigatureGlyph = FT_NEXT_USHORT( p ); + if ( LigatureGlyph >= otvalid->glyph_count ) + FT_INVALID_DATA; + + CompCount = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (CompCount = %d)\n", CompCount )); + + if ( CompCount == 0 ) + FT_INVALID_DATA; + + CompCount--; + + OTV_LIMIT_CHECK( CompCount * 2 ); /* Component */ + + /* no need to check the Component glyph indices */ + + OTV_EXIT; + } + + + static void + otv_LigatureSubst_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table; + FT_UInt SubstFormat; + + + OTV_NAME_ENTER( "LigatureSubst" ); + + OTV_LIMIT_CHECK( 2 ); + SubstFormat = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (format %d)\n", SubstFormat )); + + switch ( SubstFormat ) + { + case 1: + OTV_NEST3( LigatureSubstFormat1, LigatureSet, Ligature ); + OTV_RUN( table, otvalid ); + break; + + default: + FT_INVALID_FORMAT; + } + + OTV_EXIT; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB LOOKUP TYPE 5 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* sets otvalid->extra1 (lookup count) */ + + static void + otv_ContextSubst_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table; + FT_UInt SubstFormat; + + + OTV_NAME_ENTER( "ContextSubst" ); + + OTV_LIMIT_CHECK( 2 ); + SubstFormat = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (format %d)\n", SubstFormat )); + + switch ( SubstFormat ) + { + case 1: + /* no need to check glyph indices/classes used as input for these */ + /* context rules since even invalid glyph indices/classes return */ + /* meaningful results */ + + otvalid->extra1 = otvalid->lookup_count; + OTV_NEST3( ContextSubstFormat1, SubRuleSet, SubRule ); + OTV_RUN( table, otvalid ); + break; + + case 2: + /* no need to check glyph indices/classes used as input for these */ + /* context rules since even invalid glyph indices/classes return */ + /* meaningful results */ + + OTV_NEST3( ContextSubstFormat2, SubClassSet, SubClassRule ); + OTV_RUN( table, otvalid ); + break; + + case 3: + OTV_NEST1( ContextSubstFormat3 ); + OTV_RUN( table, otvalid ); + break; + + default: + FT_INVALID_FORMAT; + } + + OTV_EXIT; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB LOOKUP TYPE 6 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* sets otvalid->extra1 (lookup count) */ + + static void + otv_ChainContextSubst_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table; + FT_UInt SubstFormat; + + + OTV_NAME_ENTER( "ChainContextSubst" ); + + OTV_LIMIT_CHECK( 2 ); + SubstFormat = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (format %d)\n", SubstFormat )); + + switch ( SubstFormat ) + { + case 1: + /* no need to check glyph indices/classes used as input for these */ + /* context rules since even invalid glyph indices/classes return */ + /* meaningful results */ + + otvalid->extra1 = otvalid->lookup_count; + OTV_NEST3( ChainContextSubstFormat1, + ChainSubRuleSet, ChainSubRule ); + OTV_RUN( table, otvalid ); + break; + + case 2: + /* no need to check glyph indices/classes used as input for these */ + /* context rules since even invalid glyph indices/classes return */ + /* meaningful results */ + + OTV_NEST3( ChainContextSubstFormat2, + ChainSubClassSet, ChainSubClassRule ); + OTV_RUN( table, otvalid ); + break; + + case 3: + OTV_NEST1( ChainContextSubstFormat3 ); + OTV_RUN( table, otvalid ); + break; + + default: + FT_INVALID_FORMAT; + } + + OTV_EXIT; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB LOOKUP TYPE 7 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* uses otvalid->type_funcs */ + + static void + otv_ExtensionSubst_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table; + FT_UInt SubstFormat; + + + OTV_NAME_ENTER( "ExtensionSubst" ); + + OTV_LIMIT_CHECK( 2 ); + SubstFormat = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (format %d)\n", SubstFormat )); + + switch ( SubstFormat ) + { + case 1: /* ExtensionSubstFormat1 */ + { + FT_UInt ExtensionLookupType; + FT_ULong ExtensionOffset; + OTV_Validate_Func validate; + + + OTV_LIMIT_CHECK( 6 ); + ExtensionLookupType = FT_NEXT_USHORT( p ); + ExtensionOffset = FT_NEXT_ULONG( p ); + + if ( ExtensionLookupType == 0 || + ExtensionLookupType == 7 || + ExtensionLookupType > 8 ) + FT_INVALID_DATA; + + validate = otvalid->type_funcs[ExtensionLookupType - 1]; + validate( table + ExtensionOffset, otvalid ); + } + break; + + default: + FT_INVALID_FORMAT; + } + + OTV_EXIT; + } + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB LOOKUP TYPE 8 *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* uses otvalid->glyph_count */ + + static void + otv_ReverseChainSingleSubst_validate( FT_Bytes table, + OTV_Validator otvalid ) + { + FT_Bytes p = table, Coverage; + FT_UInt SubstFormat; + FT_UInt BacktrackGlyphCount, LookaheadGlyphCount, GlyphCount; + + + OTV_NAME_ENTER( "ReverseChainSingleSubst" ); + + OTV_LIMIT_CHECK( 2 ); + SubstFormat = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (format %d)\n", SubstFormat )); + + switch ( SubstFormat ) + { + case 1: /* ReverseChainSingleSubstFormat1 */ + OTV_LIMIT_CHECK( 4 ); + Coverage = table + FT_NEXT_USHORT( p ); + BacktrackGlyphCount = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (BacktrackGlyphCount = %d)\n", BacktrackGlyphCount )); + + otv_Coverage_validate( Coverage, otvalid, -1 ); + + OTV_LIMIT_CHECK( BacktrackGlyphCount * 2 + 2 ); + + for ( ; BacktrackGlyphCount > 0; BacktrackGlyphCount-- ) + otv_Coverage_validate( table + FT_NEXT_USHORT( p ), otvalid, -1 ); + + LookaheadGlyphCount = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (LookaheadGlyphCount = %d)\n", LookaheadGlyphCount )); + + OTV_LIMIT_CHECK( LookaheadGlyphCount * 2 + 2 ); + + for ( ; LookaheadGlyphCount > 0; LookaheadGlyphCount-- ) + otv_Coverage_validate( table + FT_NEXT_USHORT( p ), otvalid, -1 ); + + GlyphCount = FT_NEXT_USHORT( p ); + + OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount )); + + if ( GlyphCount != otv_Coverage_get_count( Coverage ) ) + FT_INVALID_DATA; + + OTV_LIMIT_CHECK( GlyphCount * 2 ); + + /* Substitute */ + for ( ; GlyphCount > 0; GlyphCount-- ) + if ( FT_NEXT_USHORT( p ) >= otvalid->glyph_count ) + FT_INVALID_DATA; + + break; + + default: + FT_INVALID_FORMAT; + } + + OTV_EXIT; + } + + + static const OTV_Validate_Func otv_gsub_validate_funcs[8] = + { + otv_SingleSubst_validate, + otv_MultipleSubst_validate, + otv_AlternateSubst_validate, + otv_LigatureSubst_validate, + otv_ContextSubst_validate, + otv_ChainContextSubst_validate, + otv_ExtensionSubst_validate, + otv_ReverseChainSingleSubst_validate + }; + + + /*************************************************************************/ + /*************************************************************************/ + /***** *****/ + /***** GSUB TABLE *****/ + /***** *****/ + /*************************************************************************/ + /*************************************************************************/ + + /* sets otvalid->type_count */ + /* sets otvalid->type_funcs */ + /* sets otvalid->glyph_count */ + + FT_LOCAL_DEF( void ) + otv_GSUB_validate( FT_Bytes table, + FT_UInt glyph_count, + FT_Validator ftvalid ) + { + OTV_ValidatorRec otvalidrec; + OTV_Validator otvalid = &otvalidrec; + FT_Bytes p = table; + FT_UInt table_size; + FT_UShort version; + FT_UInt ScriptList, FeatureList, LookupList; + + OTV_OPTIONAL_TABLE32( featureVariations ); + + + otvalid->root = ftvalid; + + FT_TRACE3(( "validating GSUB table\n" )); + OTV_INIT; + + OTV_LIMIT_CHECK( 4 ); + + if ( FT_NEXT_USHORT( p ) != 1 ) /* majorVersion */ + FT_INVALID_FORMAT; + + version = FT_NEXT_USHORT( p ); /* minorVersion */ + + table_size = 10; + switch ( version ) + { + case 0: + OTV_LIMIT_CHECK( 6 ); + break; + + case 1: + OTV_LIMIT_CHECK( 10 ); + table_size += 4; + break; + + default: + FT_INVALID_FORMAT; + } + + ScriptList = FT_NEXT_USHORT( p ); + FeatureList = FT_NEXT_USHORT( p ); + LookupList = FT_NEXT_USHORT( p ); + + otvalid->type_count = 8; + otvalid->type_funcs = (OTV_Validate_Func*)otv_gsub_validate_funcs; + otvalid->glyph_count = glyph_count; + + otv_LookupList_validate( table + LookupList, + otvalid ); + otv_FeatureList_validate( table + FeatureList, table + LookupList, + otvalid ); + otv_ScriptList_validate( table + ScriptList, table + FeatureList, + otvalid ); + + if ( version > 0 ) + { + OTV_OPTIONAL_OFFSET32( featureVariations ); + OTV_SIZE_CHECK32( featureVariations ); + if ( featureVariations ) + OTV_TRACE(( " [omitting featureVariations validation]\n" )); /* XXX */ + } + + FT_TRACE4(( "\n" )); + } + + +/* END */ |