reactos/lib/3rdparty/freetype/src/gxvalid/gxvmort2.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  gxvmort2.c                                                             */
   4 /*                                                                         */
   5 /*    TrueTypeGX/AAT mort table validation                                 */
   6 /*    body for type2 (Ligature Substitution) subtable.                     */
   7 /*                                                                         */
   8 /*  Copyright 2005-2016 by                                                 */
   9 /*  suzuki toshiya, Masatake YAMATO, Red Hat K.K.,                         */
  10 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
  11 /*                                                                         */
  12 /*  This file is part of the FreeType project, and may only be used,       */
  13 /*  modified, and distributed under the terms of the FreeType project      */
  14 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  15 /*  this file you indicate that you have read the license and              */
  16 /*  understand and accept it fully.                                        */
  17 /*                                                                         */
  18 /***************************************************************************/
  19
  20 /***************************************************************************/
  21 /*                                                                         */
  22 /* gxvalid is derived from both gxlayout module and otvalid module.        */
  23 /* Development of gxlayout is supported by the Information-technology      */
  24 /* Promotion Agency(IPA), Japan.                                           */
  25 /*                                                                         */
  26 /***************************************************************************/
  27
  28
  29 #include "gxvmort.h"
  30
  31
  32   /*************************************************************************/
  33   /*                                                                       */
  34   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  35   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  36   /* messages during execution.                                            */
  37   /*                                                                       */
  38 #undef  FT_COMPONENT
  39 #define FT_COMPONENT  trace_gxvmort
  40
  41
  42   typedef struct  GXV_mort_subtable_type2_StateOptRec_
  43   {
  44     FT_UShort  ligActionTable;
  45     FT_UShort  componentTable;
  46     FT_UShort  ligatureTable;
  47     FT_UShort  ligActionTable_length;
  48     FT_UShort  componentTable_length;
  49     FT_UShort  ligatureTable_length;
  50
  51   }  GXV_mort_subtable_type2_StateOptRec,
  52     *GXV_mort_subtable_type2_StateOptRecData;
  53
  54 #define GXV_MORT_SUBTABLE_TYPE2_HEADER_SIZE \
  55           ( GXV_STATETABLE_HEADER_SIZE + 2 + 2 + 2 )
  56
  57
  58   static void
  59   gxv_mort_subtable_type2_opttable_load( FT_Bytes       table,
  60                                          FT_Bytes       limit,
  61                                          GXV_Validator  gxvalid )
  62   {
  63     FT_Bytes  p = table;
  64     GXV_mort_subtable_type2_StateOptRecData  optdata =
  65       (GXV_mort_subtable_type2_StateOptRecData)gxvalid->statetable.optdata;
  66
  67
  68     GXV_LIMIT_CHECK( 2 + 2 + 2 );
  69     optdata->ligActionTable = FT_NEXT_USHORT( p );
  70     optdata->componentTable = FT_NEXT_USHORT( p );
  71     optdata->ligatureTable  = FT_NEXT_USHORT( p );
  72
  73     GXV_TRACE(( "offset to ligActionTable=0x%04x\n",
  74                 optdata->ligActionTable ));
  75     GXV_TRACE(( "offset to componentTable=0x%04x\n",
  76                 optdata->componentTable ));
  77     GXV_TRACE(( "offset to ligatureTable=0x%04x\n",
  78                 optdata->ligatureTable ));
  79   }
  80
  81
  82   static void
  83   gxv_mort_subtable_type2_subtable_setup( FT_UShort      table_size,
  84                                           FT_UShort      classTable,
  85                                           FT_UShort      stateArray,
  86                                           FT_UShort      entryTable,
  87                                           FT_UShort      *classTable_length_p,
  88                                           FT_UShort      *stateArray_length_p,
  89                                           FT_UShort      *entryTable_length_p,
  90                                           GXV_Validator  gxvalid )
  91   {
  92     FT_UShort  o[6];
  93     FT_UShort  *l[6];
  94     FT_UShort  buff[7];
  95
  96     GXV_mort_subtable_type2_StateOptRecData  optdata =
  97       (GXV_mort_subtable_type2_StateOptRecData)gxvalid->statetable.optdata;
  98
  99
 100     GXV_NAME_ENTER( "subtable boundaries setup" );
 101
 102     o[0] = classTable;
 103     o[1] = stateArray;
 104     o[2] = entryTable;
 105     o[3] = optdata->ligActionTable;
 106     o[4] = optdata->componentTable;
 107     o[5] = optdata->ligatureTable;
 108     l[0] = classTable_length_p;
 109     l[1] = stateArray_length_p;
 110     l[2] = entryTable_length_p;
 111     l[3] = &(optdata->ligActionTable_length);
 112     l[4] = &(optdata->componentTable_length);
 113     l[5] = &(optdata->ligatureTable_length);
 114
 115     gxv_set_length_by_ushort_offset( o, l, buff, 6, table_size, gxvalid );
 116
 117     GXV_TRACE(( "classTable: offset=0x%04x length=0x%04x\n",
 118                 classTable, *classTable_length_p ));
 119     GXV_TRACE(( "stateArray: offset=0x%04x length=0x%04x\n",
 120                 stateArray, *stateArray_length_p ));
 121     GXV_TRACE(( "entryTable: offset=0x%04x length=0x%04x\n",
 122                 entryTable, *entryTable_length_p ));
 123     GXV_TRACE(( "ligActionTable: offset=0x%04x length=0x%04x\n",
 124                 optdata->ligActionTable,
 125                 optdata->ligActionTable_length ));
 126     GXV_TRACE(( "componentTable: offset=0x%04x length=0x%04x\n",
 127                 optdata->componentTable,
 128                 optdata->componentTable_length ));
 129     GXV_TRACE(( "ligatureTable:  offset=0x%04x length=0x%04x\n",
 130                 optdata->ligatureTable,
 131                 optdata->ligatureTable_length ));
 132
 133     GXV_EXIT;
 134   }
 135
 136
 137   static void
 138   gxv_mort_subtable_type2_ligActionOffset_validate(
 139     FT_Bytes       table,
 140     FT_UShort      ligActionOffset,
 141     GXV_Validator  gxvalid )
 142   {
 143     /* access ligActionTable */
 144     GXV_mort_subtable_type2_StateOptRecData  optdata =
 145       (GXV_mort_subtable_type2_StateOptRecData)gxvalid->statetable.optdata;
 146
 147     FT_Bytes lat_base  = table + optdata->ligActionTable;
 148     FT_Bytes p         = table + ligActionOffset;
 149     FT_Bytes lat_limit = lat_base + optdata->ligActionTable;
 150
 151
 152     GXV_32BIT_ALIGNMENT_VALIDATE( ligActionOffset );
 153     if ( p < lat_base )
 154     {
 155       GXV_TRACE(( "too short offset 0x%04x: p < lat_base (%d byte rewind)\n",
 156                   ligActionOffset, lat_base - p ));
 157
 158       /* FontValidator, ftxvalidator, ftxdumperfuser warn but continue */
 159       GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
 160     }
 161     else if ( lat_limit < p )
 162     {
 163       GXV_TRACE(( "too large offset 0x%04x: lat_limit < p (%d byte overrun)\n",
 164                   ligActionOffset, p - lat_limit ));
 165
 166       /* FontValidator, ftxvalidator, ftxdumperfuser warn but continue */
 167       GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
 168     }
 169     else
 170     {
 171       /* validate entry in ligActionTable */
 172       FT_ULong   lig_action;
 173 #ifdef GXV_LOAD_UNUSED_VARS
 174       FT_UShort  last;
 175       FT_UShort  store;
 176 #endif
 177       FT_ULong   offset;
 178
 179
 180       lig_action = FT_NEXT_ULONG( p );
 181 #ifdef GXV_LOAD_UNUSED_VARS
 182       last   = (FT_UShort)( ( lig_action >> 31 ) & 1 );
 183       store  = (FT_UShort)( ( lig_action >> 30 ) & 1 );
 184 #endif
 185
 186       /* Apple spec defines this offset as a word offset */
 187       offset = lig_action & 0x3FFFFFFFUL;
 188       if ( offset * 2 < optdata->ligatureTable )
 189       {
 190         GXV_TRACE(( "too short offset 0x%08x:"
 191                     " 2 x offset < ligatureTable (%d byte rewind)\n",
 192                      offset, optdata->ligatureTable - offset * 2 ));
 193
 194         GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
 195       } else if ( offset * 2 >
 196                   optdata->ligatureTable + optdata->ligatureTable_length )
 197       {
 198         GXV_TRACE(( "too long offset 0x%08x:"
 199                     " 2 x offset > ligatureTable + ligatureTable_length"
 200                     " (%d byte overrun)\n",
 201                      offset,
 202                      optdata->ligatureTable + optdata->ligatureTable_length
 203                      - offset * 2 ));
 204
 205         GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
 206       }
 207     }
 208   }
 209
 210
 211   static void
 212   gxv_mort_subtable_type2_entry_validate(
 213     FT_Byte                         state,
 214     FT_UShort                       flags,
 215     GXV_StateTable_GlyphOffsetCPtr  glyphOffset_p,
 216     FT_Bytes                        table,
 217     FT_Bytes                        limit,
 218     GXV_Validator                   gxvalid )
 219   {
 220 #ifdef GXV_LOAD_UNUSED_VARS
 221     FT_UShort setComponent;
 222     FT_UShort dontAdvance;
 223 #endif
 224     FT_UShort offset;
 225
 226     FT_UNUSED( state );
 227     FT_UNUSED( glyphOffset_p );
 228     FT_UNUSED( limit );
 229
 230
 231 #ifdef GXV_LOAD_UNUSED_VARS
 232     setComponent = (FT_UShort)( ( flags >> 15 ) & 1 );
 233     dontAdvance  = (FT_UShort)( ( flags >> 14 ) & 1 );
 234 #endif
 235
 236     offset = (FT_UShort)( flags & 0x3FFFU );
 237
 238     if ( 0 < offset )
 239       gxv_mort_subtable_type2_ligActionOffset_validate( table, offset,
 240                                                         gxvalid );
 241   }
 242
 243
 244   static void
 245   gxv_mort_subtable_type2_ligatureTable_validate( FT_Bytes       table,
 246                                                   GXV_Validator  gxvalid )
 247   {
 248     GXV_mort_subtable_type2_StateOptRecData  optdata =
 249       (GXV_mort_subtable_type2_StateOptRecData)gxvalid->statetable.optdata;
 250
 251     FT_Bytes p     = table + optdata->ligatureTable;
 252     FT_Bytes limit = table + optdata->ligatureTable
 253                            + optdata->ligatureTable_length;
 254
 255
 256     GXV_NAME_ENTER( "mort chain subtable type2 - substitutionTable" );
 257     if ( 0 != optdata->ligatureTable )
 258     {
 259       /* Apple does not give specification of ligatureTable format */
 260       while ( p < limit )
 261       {
 262         FT_UShort  lig_gid;
 263
 264
 265         GXV_LIMIT_CHECK( 2 );
 266         lig_gid = FT_NEXT_USHORT( p );
 267
 268         if ( gxvalid->face->num_glyphs < lig_gid )
 269           GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
 270       }
 271     }
 272     GXV_EXIT;
 273   }
 274
 275
 276   FT_LOCAL_DEF( void )
 277   gxv_mort_subtable_type2_validate( FT_Bytes       table,
 278                                     FT_Bytes       limit,
 279                                     GXV_Validator  gxvalid )
 280   {
 281     FT_Bytes  p = table;
 282
 283     GXV_mort_subtable_type2_StateOptRec  lig_rec;
 284
 285
 286     GXV_NAME_ENTER( "mort chain subtable type2 (Ligature Substitution)" );
 287
 288     GXV_LIMIT_CHECK( GXV_MORT_SUBTABLE_TYPE2_HEADER_SIZE );
 289
 290     gxvalid->statetable.optdata =
 291       &lig_rec;
 292     gxvalid->statetable.optdata_load_func =
 293       gxv_mort_subtable_type2_opttable_load;
 294     gxvalid->statetable.subtable_setup_func =
 295       gxv_mort_subtable_type2_subtable_setup;
 296     gxvalid->statetable.entry_glyphoffset_fmt =
 297       GXV_GLYPHOFFSET_NONE;
 298     gxvalid->statetable.entry_validate_func =
 299       gxv_mort_subtable_type2_entry_validate;
 300
 301     gxv_StateTable_validate( p, limit, gxvalid );
 302
 303     p += gxvalid->subtable_length;
 304     gxv_mort_subtable_type2_ligatureTable_validate( table, gxvalid );
 305
 306     gxvalid->subtable_length = (FT_ULong)( p - table );
 307
 308     GXV_EXIT;
 309   }
 310
 311
 312 /* END */