1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
|
/***************************************************************************/
/* */
/* gxvmort2.c */
/* */
/* TrueTypeGX/AAT mort table validation */
/* body for type2 (Ligature Substitution) subtable. */
/* */
/* Copyright 2005-2018 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 "gxvmort.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 trace_gxvmort
typedef struct GXV_mort_subtable_type2_StateOptRec_
{
FT_UShort ligActionTable;
FT_UShort componentTable;
FT_UShort ligatureTable;
FT_UShort ligActionTable_length;
FT_UShort componentTable_length;
FT_UShort ligatureTable_length;
} GXV_mort_subtable_type2_StateOptRec,
*GXV_mort_subtable_type2_StateOptRecData;
#define GXV_MORT_SUBTABLE_TYPE2_HEADER_SIZE \
( GXV_STATETABLE_HEADER_SIZE + 2 + 2 + 2 )
static void
gxv_mort_subtable_type2_opttable_load( FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
FT_Bytes p = table;
GXV_mort_subtable_type2_StateOptRecData optdata =
(GXV_mort_subtable_type2_StateOptRecData)gxvalid->statetable.optdata;
GXV_LIMIT_CHECK( 2 + 2 + 2 );
optdata->ligActionTable = FT_NEXT_USHORT( p );
optdata->componentTable = FT_NEXT_USHORT( p );
optdata->ligatureTable = FT_NEXT_USHORT( p );
GXV_TRACE(( "offset to ligActionTable=0x%04x\n",
optdata->ligActionTable ));
GXV_TRACE(( "offset to componentTable=0x%04x\n",
optdata->componentTable ));
GXV_TRACE(( "offset to ligatureTable=0x%04x\n",
optdata->ligatureTable ));
}
static void
gxv_mort_subtable_type2_subtable_setup( FT_UShort table_size,
FT_UShort classTable,
FT_UShort stateArray,
FT_UShort entryTable,
FT_UShort *classTable_length_p,
FT_UShort *stateArray_length_p,
FT_UShort *entryTable_length_p,
GXV_Validator gxvalid )
{
FT_UShort o[6];
FT_UShort *l[6];
FT_UShort buff[7];
GXV_mort_subtable_type2_StateOptRecData optdata =
(GXV_mort_subtable_type2_StateOptRecData)gxvalid->statetable.optdata;
GXV_NAME_ENTER( "subtable boundaries setup" );
o[0] = classTable;
o[1] = stateArray;
o[2] = entryTable;
o[3] = optdata->ligActionTable;
o[4] = optdata->componentTable;
o[5] = optdata->ligatureTable;
l[0] = classTable_length_p;
l[1] = stateArray_length_p;
l[2] = entryTable_length_p;
l[3] = &(optdata->ligActionTable_length);
l[4] = &(optdata->componentTable_length);
l[5] = &(optdata->ligatureTable_length);
gxv_set_length_by_ushort_offset( o, l, buff, 6, table_size, gxvalid );
GXV_TRACE(( "classTable: offset=0x%04x length=0x%04x\n",
classTable, *classTable_length_p ));
GXV_TRACE(( "stateArray: offset=0x%04x length=0x%04x\n",
stateArray, *stateArray_length_p ));
GXV_TRACE(( "entryTable: offset=0x%04x length=0x%04x\n",
entryTable, *entryTable_length_p ));
GXV_TRACE(( "ligActionTable: offset=0x%04x length=0x%04x\n",
optdata->ligActionTable,
optdata->ligActionTable_length ));
GXV_TRACE(( "componentTable: offset=0x%04x length=0x%04x\n",
optdata->componentTable,
optdata->componentTable_length ));
GXV_TRACE(( "ligatureTable: offset=0x%04x length=0x%04x\n",
optdata->ligatureTable,
optdata->ligatureTable_length ));
GXV_EXIT;
}
static void
gxv_mort_subtable_type2_ligActionOffset_validate(
FT_Bytes table,
FT_UShort ligActionOffset,
GXV_Validator gxvalid )
{
/* access ligActionTable */
GXV_mort_subtable_type2_StateOptRecData optdata =
(GXV_mort_subtable_type2_StateOptRecData)gxvalid->statetable.optdata;
FT_Bytes lat_base = table + optdata->ligActionTable;
FT_Bytes p = table + ligActionOffset;
FT_Bytes lat_limit = lat_base + optdata->ligActionTable;
GXV_32BIT_ALIGNMENT_VALIDATE( ligActionOffset );
if ( p < lat_base )
{
GXV_TRACE(( "too short offset 0x%04x: p < lat_base (%d byte rewind)\n",
ligActionOffset, lat_base - p ));
/* FontValidator, ftxvalidator, ftxdumperfuser warn but continue */
GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
}
else if ( lat_limit < p )
{
GXV_TRACE(( "too large offset 0x%04x: lat_limit < p (%d byte overrun)\n",
ligActionOffset, p - lat_limit ));
/* FontValidator, ftxvalidator, ftxdumperfuser warn but continue */
GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
}
else
{
/* validate entry in ligActionTable */
FT_ULong lig_action;
#ifdef GXV_LOAD_UNUSED_VARS
FT_UShort last;
FT_UShort store;
#endif
FT_ULong offset;
lig_action = FT_NEXT_ULONG( p );
#ifdef GXV_LOAD_UNUSED_VARS
last = (FT_UShort)( ( lig_action >> 31 ) & 1 );
store = (FT_UShort)( ( lig_action >> 30 ) & 1 );
#endif
/* Apple spec defines this offset as a word offset */
offset = lig_action & 0x3FFFFFFFUL;
if ( offset * 2 < optdata->ligatureTable )
{
GXV_TRACE(( "too short offset 0x%08x:"
" 2 x offset < ligatureTable (%d byte rewind)\n",
offset, optdata->ligatureTable - offset * 2 ));
GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
} else if ( offset * 2 >
optdata->ligatureTable + optdata->ligatureTable_length )
{
GXV_TRACE(( "too long offset 0x%08x:"
" 2 x offset > ligatureTable + ligatureTable_length"
" (%d byte overrun)\n",
offset,
optdata->ligatureTable + optdata->ligatureTable_length
- offset * 2 ));
GXV_SET_ERR_IF_PARANOID( FT_INVALID_OFFSET );
}
}
}
static void
gxv_mort_subtable_type2_entry_validate(
FT_Byte state,
FT_UShort flags,
GXV_StateTable_GlyphOffsetCPtr glyphOffset_p,
FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
#ifdef GXV_LOAD_UNUSED_VARS
FT_UShort setComponent;
FT_UShort dontAdvance;
#endif
FT_UShort offset;
FT_UNUSED( state );
FT_UNUSED( glyphOffset_p );
FT_UNUSED( limit );
#ifdef GXV_LOAD_UNUSED_VARS
setComponent = (FT_UShort)( ( flags >> 15 ) & 1 );
dontAdvance = (FT_UShort)( ( flags >> 14 ) & 1 );
#endif
offset = (FT_UShort)( flags & 0x3FFFU );
if ( 0 < offset )
gxv_mort_subtable_type2_ligActionOffset_validate( table, offset,
gxvalid );
}
static void
gxv_mort_subtable_type2_ligatureTable_validate( FT_Bytes table,
GXV_Validator gxvalid )
{
GXV_mort_subtable_type2_StateOptRecData optdata =
(GXV_mort_subtable_type2_StateOptRecData)gxvalid->statetable.optdata;
FT_Bytes p = table + optdata->ligatureTable;
FT_Bytes limit = table + optdata->ligatureTable
+ optdata->ligatureTable_length;
GXV_NAME_ENTER( "mort chain subtable type2 - substitutionTable" );
if ( 0 != optdata->ligatureTable )
{
/* Apple does not give specification of ligatureTable format */
while ( p < limit )
{
FT_UShort lig_gid;
GXV_LIMIT_CHECK( 2 );
lig_gid = FT_NEXT_USHORT( p );
if ( gxvalid->face->num_glyphs < lig_gid )
GXV_SET_ERR_IF_PARANOID( FT_INVALID_GLYPH_ID );
}
}
GXV_EXIT;
}
FT_LOCAL_DEF( void )
gxv_mort_subtable_type2_validate( FT_Bytes table,
FT_Bytes limit,
GXV_Validator gxvalid )
{
FT_Bytes p = table;
GXV_mort_subtable_type2_StateOptRec lig_rec;
GXV_NAME_ENTER( "mort chain subtable type2 (Ligature Substitution)" );
GXV_LIMIT_CHECK( GXV_MORT_SUBTABLE_TYPE2_HEADER_SIZE );
gxvalid->statetable.optdata =
&lig_rec;
gxvalid->statetable.optdata_load_func =
gxv_mort_subtable_type2_opttable_load;
gxvalid->statetable.subtable_setup_func =
gxv_mort_subtable_type2_subtable_setup;
gxvalid->statetable.entry_glyphoffset_fmt =
GXV_GLYPHOFFSET_NONE;
gxvalid->statetable.entry_validate_func =
gxv_mort_subtable_type2_entry_validate;
gxv_StateTable_validate( p, limit, gxvalid );
p += gxvalid->subtable_length;
gxv_mort_subtable_type2_ligatureTable_validate( table, gxvalid );
gxvalid->subtable_length = (FT_ULong)( p - table );
GXV_EXIT;
}
/* END */
|