1 /***************************************************************************/ 2 /* */ 3 /* gxvmort.c */ 4 /* */ 5 /* TrueTypeGX/AAT mort table validation (body). */ 6 /* */ 7 /* Copyright 2005, 2013 by suzuki toshiya, Masatake YAMATO, Red Hat K.K., */ 8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */ 9 /* */ 10 /* This file is part of the FreeType project, and may only be used, */ 11 /* modified, and distributed under the terms of the FreeType project */ 12 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ 13 /* this file you indicate that you have read the license and */ 14 /* understand and accept it fully. */ 15 /* */ 16 /***************************************************************************/ 17 18 /***************************************************************************/ 19 /* */ 20 /* gxvalid is derived from both gxlayout module and otvalid module. */ 21 /* Development of gxlayout is supported by the Information-technology */ 22 /* Promotion Agency(IPA), Japan. */ 23 /* */ 24 /***************************************************************************/ 25 26 27 #include "gxvmort.h" 28 #include "gxvfeat.h" 29 30 31 /*************************************************************************/ 32 /* */ 33 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ 34 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ 35 /* messages during execution. */ 36 /* */ 37 #undef FT_COMPONENT 38 #define FT_COMPONENT trace_gxvmort 39 40 41 static void gxv_mort_feature_validate(GXV_mort_feature f,GXV_Validator valid)42 gxv_mort_feature_validate( GXV_mort_feature f, 43 GXV_Validator valid ) 44 { 45 if ( f->featureType >= gxv_feat_registry_length ) 46 { 47 GXV_TRACE(( "featureType %d is out of registered range, " 48 "setting %d is unchecked\n", 49 f->featureType, f->featureSetting )); 50 GXV_SET_ERR_IF_PARANOID( FT_INVALID_DATA ); 51 } 52 else if ( !gxv_feat_registry[f->featureType].existence ) 53 { 54 GXV_TRACE(( "featureType %d is within registered area " 55 "but undefined, setting %d is unchecked\n", 56 f->featureType, f->featureSetting )); 57 GXV_SET_ERR_IF_PARANOID( FT_INVALID_DATA ); 58 } 59 else 60 { 61 FT_Byte nSettings_max; 62 63 64 /* nSettings in gxvfeat.c is halved for exclusive on/off settings */ 65 nSettings_max = gxv_feat_registry[f->featureType].nSettings; 66 if ( gxv_feat_registry[f->featureType].exclusive ) 67 nSettings_max = (FT_Byte)( 2 * nSettings_max ); 68 69 GXV_TRACE(( "featureType %d is registered", f->featureType )); 70 GXV_TRACE(( "setting %d", f->featureSetting )); 71 72 if ( f->featureSetting > nSettings_max ) 73 { 74 GXV_TRACE(( "out of defined range %d", nSettings_max )); 75 GXV_SET_ERR_IF_PARANOID( FT_INVALID_DATA ); 76 } 77 GXV_TRACE(( "\n" )); 78 } 79 80 /* TODO: enableFlags must be unique value in specified chain? */ 81 } 82 83 84 /* 85 * nFeatureFlags is typed to FT_ULong to accept that in 86 * mort (typed FT_UShort) and morx (typed FT_ULong). 87 */ 88 FT_LOCAL_DEF( void ) gxv_mort_featurearray_validate(FT_Bytes table,FT_Bytes limit,FT_ULong nFeatureFlags,GXV_Validator valid)89 gxv_mort_featurearray_validate( FT_Bytes table, 90 FT_Bytes limit, 91 FT_ULong nFeatureFlags, 92 GXV_Validator valid ) 93 { 94 FT_Bytes p = table; 95 FT_ULong i; 96 97 GXV_mort_featureRec f = GXV_MORT_FEATURE_OFF; 98 99 100 GXV_NAME_ENTER( "mort feature list" ); 101 for ( i = 0; i < nFeatureFlags; i++ ) 102 { 103 GXV_LIMIT_CHECK( 2 + 2 + 4 + 4 ); 104 f.featureType = FT_NEXT_USHORT( p ); 105 f.featureSetting = FT_NEXT_USHORT( p ); 106 f.enableFlags = FT_NEXT_ULONG( p ); 107 f.disableFlags = FT_NEXT_ULONG( p ); 108 109 gxv_mort_feature_validate( &f, valid ); 110 } 111 112 if ( !IS_GXV_MORT_FEATURE_OFF( f ) ) 113 FT_INVALID_DATA; 114 115 valid->subtable_length = p - table; 116 GXV_EXIT; 117 } 118 119 120 FT_LOCAL_DEF( void ) gxv_mort_coverage_validate(FT_UShort coverage,GXV_Validator valid)121 gxv_mort_coverage_validate( FT_UShort coverage, 122 GXV_Validator valid ) 123 { 124 FT_UNUSED( valid ); 125 126 #ifdef FT_DEBUG_LEVEL_TRACE 127 if ( coverage & 0x8000U ) 128 GXV_TRACE(( " this subtable is for vertical text only\n" )); 129 else 130 GXV_TRACE(( " this subtable is for horizontal text only\n" )); 131 132 if ( coverage & 0x4000 ) 133 GXV_TRACE(( " this subtable is applied to glyph array " 134 "in descending order\n" )); 135 else 136 GXV_TRACE(( " this subtable is applied to glyph array " 137 "in ascending order\n" )); 138 139 if ( coverage & 0x2000 ) 140 GXV_TRACE(( " this subtable is forcibly applied to " 141 "vertical/horizontal text\n" )); 142 143 if ( coverage & 0x1FF8 ) 144 GXV_TRACE(( " coverage has non-zero bits in reserved area\n" )); 145 #endif 146 } 147 148 149 static void gxv_mort_subtables_validate(FT_Bytes table,FT_Bytes limit,FT_UShort nSubtables,GXV_Validator valid)150 gxv_mort_subtables_validate( FT_Bytes table, 151 FT_Bytes limit, 152 FT_UShort nSubtables, 153 GXV_Validator valid ) 154 { 155 FT_Bytes p = table; 156 157 GXV_Validate_Func fmt_funcs_table[] = 158 { 159 gxv_mort_subtable_type0_validate, /* 0 */ 160 gxv_mort_subtable_type1_validate, /* 1 */ 161 gxv_mort_subtable_type2_validate, /* 2 */ 162 NULL, /* 3 */ 163 gxv_mort_subtable_type4_validate, /* 4 */ 164 gxv_mort_subtable_type5_validate, /* 5 */ 165 166 }; 167 168 FT_UShort i; 169 170 171 GXV_NAME_ENTER( "subtables in a chain" ); 172 173 for ( i = 0; i < nSubtables; i++ ) 174 { 175 GXV_Validate_Func func; 176 177 FT_UShort length; 178 FT_UShort coverage; 179 #ifdef GXV_LOAD_UNUSED_VARS 180 FT_ULong subFeatureFlags; 181 #endif 182 FT_UInt type; 183 FT_UInt rest; 184 185 186 GXV_LIMIT_CHECK( 2 + 2 + 4 ); 187 length = FT_NEXT_USHORT( p ); 188 coverage = FT_NEXT_USHORT( p ); 189 #ifdef GXV_LOAD_UNUSED_VARS 190 subFeatureFlags = FT_NEXT_ULONG( p ); 191 #else 192 p += 4; 193 #endif 194 195 GXV_TRACE(( "validating chain subtable %d/%d (%d bytes)\n", 196 i + 1, nSubtables, length )); 197 type = coverage & 0x0007; 198 rest = length - ( 2 + 2 + 4 ); 199 200 GXV_LIMIT_CHECK( rest ); 201 gxv_mort_coverage_validate( coverage, valid ); 202 203 if ( type > 5 ) 204 FT_INVALID_FORMAT; 205 206 func = fmt_funcs_table[type]; 207 if ( func == NULL ) 208 GXV_TRACE(( "morx type %d is reserved\n", type )); 209 210 func( p, p + rest, valid ); 211 212 p += rest; 213 /* TODO: validate subFeatureFlags */ 214 } 215 216 valid->subtable_length = p - table; 217 218 GXV_EXIT; 219 } 220 221 222 static void gxv_mort_chain_validate(FT_Bytes table,FT_Bytes limit,GXV_Validator valid)223 gxv_mort_chain_validate( FT_Bytes table, 224 FT_Bytes limit, 225 GXV_Validator valid ) 226 { 227 FT_Bytes p = table; 228 #ifdef GXV_LOAD_UNUSED_VARS 229 FT_ULong defaultFlags; 230 #endif 231 FT_ULong chainLength; 232 FT_UShort nFeatureFlags; 233 FT_UShort nSubtables; 234 235 236 GXV_NAME_ENTER( "mort chain header" ); 237 238 GXV_LIMIT_CHECK( 4 + 4 + 2 + 2 ); 239 #ifdef GXV_LOAD_UNUSED_VARS 240 defaultFlags = FT_NEXT_ULONG( p ); 241 #else 242 p += 4; 243 #endif 244 chainLength = FT_NEXT_ULONG( p ); 245 nFeatureFlags = FT_NEXT_USHORT( p ); 246 nSubtables = FT_NEXT_USHORT( p ); 247 248 gxv_mort_featurearray_validate( p, table + chainLength, 249 nFeatureFlags, valid ); 250 p += valid->subtable_length; 251 gxv_mort_subtables_validate( p, table + chainLength, nSubtables, valid ); 252 valid->subtable_length = chainLength; 253 254 /* TODO: validate defaultFlags */ 255 GXV_EXIT; 256 } 257 258 259 FT_LOCAL_DEF( void ) gxv_mort_validate(FT_Bytes table,FT_Face face,FT_Validator ftvalid)260 gxv_mort_validate( FT_Bytes table, 261 FT_Face face, 262 FT_Validator ftvalid ) 263 { 264 GXV_ValidatorRec validrec; 265 GXV_Validator valid = &validrec; 266 FT_Bytes p = table; 267 FT_Bytes limit = 0; 268 FT_ULong version; 269 FT_ULong nChains; 270 FT_ULong i; 271 272 273 valid->root = ftvalid; 274 valid->face = face; 275 limit = valid->root->limit; 276 277 FT_TRACE3(( "validating `mort' table\n" )); 278 GXV_INIT; 279 280 GXV_LIMIT_CHECK( 4 + 4 ); 281 version = FT_NEXT_ULONG( p ); 282 nChains = FT_NEXT_ULONG( p ); 283 284 if (version != 0x00010000UL) 285 FT_INVALID_FORMAT; 286 287 for ( i = 0; i < nChains; i++ ) 288 { 289 GXV_TRACE(( "validating chain %d/%d\n", i + 1, nChains )); 290 GXV_32BIT_ALIGNMENT_VALIDATE( p - table ); 291 gxv_mort_chain_validate( p, limit, valid ); 292 p += valid->subtable_length; 293 } 294 295 FT_TRACE4(( "\n" )); 296 } 297 298 299 /* END */ 300