1 /****************************************************************************
2 *
3 * gxvbsln.c
4 *
5 * TrueTypeGX/AAT bsln table validation (body).
6 *
7 * Copyright (C) 2004-2023 by
8 * suzuki toshiya, Masatake YAMATO, Red Hat K.K.,
9 * David Turner, Robert Wilhelm, and Werner Lemberg.
10 *
11 * This file is part of the FreeType project, and may only be used,
12 * modified, and distributed under the terms of the FreeType project
13 * license, LICENSE.TXT. By continuing to use, modify, or distribute
14 * this file you indicate that you have read the license and
15 * understand and accept it fully.
16 *
17 */
18
19 /****************************************************************************
20 *
21 * gxvalid is derived from both gxlayout module and otvalid module.
22 * Development of gxlayout is supported by the Information-technology
23 * Promotion Agency(IPA), Japan.
24 *
25 */
26
27
28 #include "gxvalid.h"
29 #include "gxvcommn.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 gxvbsln
40
41
42 /*************************************************************************/
43 /*************************************************************************/
44 /***** *****/
45 /***** Data and Types *****/
46 /***** *****/
47 /*************************************************************************/
48 /*************************************************************************/
49
50 #define GXV_BSLN_VALUE_COUNT 32
51 #define GXV_BSLN_VALUE_EMPTY 0xFFFFU
52
53
54 typedef struct GXV_bsln_DataRec_
55 {
56 FT_Bytes ctlPoints_p;
57 FT_UShort defaultBaseline;
58
59 } GXV_bsln_DataRec, *GXV_bsln_Data;
60
61
62 #define GXV_BSLN_DATA( field ) GXV_TABLE_DATA( bsln, field )
63
64
65 /*************************************************************************/
66 /*************************************************************************/
67 /***** *****/
68 /***** UTILITY FUNCTIONS *****/
69 /***** *****/
70 /*************************************************************************/
71 /*************************************************************************/
72
73 static void
74 gxv_bsln_LookupValue_validate( FT_UShort glyph,
75 GXV_LookupValueCPtr value_p,
76 GXV_Validator gxvalid )
77 {
78 FT_UShort v = value_p->u;
79 FT_UShort* ctlPoints;
80
81 FT_UNUSED( glyph );
82
83
84 GXV_NAME_ENTER( "lookup value" );
85
86 if ( v >= GXV_BSLN_VALUE_COUNT )
87 FT_INVALID_DATA;
88
89 ctlPoints = (FT_UShort*)GXV_BSLN_DATA( ctlPoints_p );
90 if ( ctlPoints && ctlPoints[v] == GXV_BSLN_VALUE_EMPTY )
91 FT_INVALID_DATA;
92
93 GXV_EXIT;
94 }
95
96
97 /*
98 +===============+ --------+
99 | lookup header | |
100 +===============+ |
101 | BinSrchHeader | |
102 +===============+ |
103 | lastGlyph[0] | |
104 +---------------+ |
105 | firstGlyph[0] | | head of lookup table
106 +---------------+ | +
107 | offset[0] | -> | offset [byte]
108 +===============+ | +
109 | lastGlyph[1] | | (glyphID - firstGlyph) * 2 [byte]
110 +---------------+ |
111 | firstGlyph[1] | |
112 +---------------+ |
113 | offset[1] | |
114 +===============+ |
115 |
116 ... |
117 |
118 16bit value array |
119 +===============+ |
120 | value | <-------+
121 ...
122 */
123
124 static GXV_LookupValueDesc
125 gxv_bsln_LookupFmt4_transit( FT_UShort relative_gindex,
126 GXV_LookupValueCPtr base_value_p,
127 FT_Bytes lookuptbl_limit,
128 GXV_Validator gxvalid )
129 {
130 FT_Bytes p;
131 FT_Bytes limit;
132 FT_UShort offset;
133 GXV_LookupValueDesc value;
134
135 /* XXX: check range ? */
136 offset = (FT_UShort)( base_value_p->u +
137 ( relative_gindex * sizeof ( FT_UShort ) ) );
138
139 p = gxvalid->lookuptbl_head + offset;
140 limit = lookuptbl_limit;
141 GXV_LIMIT_CHECK( 2 );
142
143 value.u = FT_NEXT_USHORT( p );
144
145 return value;
146 }
147
148
149 static void
150 gxv_bsln_parts_fmt0_validate( FT_Bytes tables,
151 FT_Bytes limit,
152 GXV_Validator gxvalid )
153 {
154 FT_Bytes p = tables;
155
156
157 GXV_NAME_ENTER( "parts format 0" );
158
159 /* deltas */
160 GXV_LIMIT_CHECK( 2 * GXV_BSLN_VALUE_COUNT );
161
162 gxvalid->table_data = NULL; /* No ctlPoints here. */
163
164 GXV_EXIT;
165 }
166
167
168 static void
169 gxv_bsln_parts_fmt1_validate( FT_Bytes tables,
170 FT_Bytes limit,
171 GXV_Validator gxvalid )
172 {
173 FT_Bytes p = tables;
174
175
176 GXV_NAME_ENTER( "parts format 1" );
177
178 /* deltas */
179 gxv_bsln_parts_fmt0_validate( p, limit, gxvalid );
180
181 /* mappingData */
182 gxvalid->lookupval_sign = GXV_LOOKUPVALUE_UNSIGNED;
183 gxvalid->lookupval_func = gxv_bsln_LookupValue_validate;
184 gxvalid->lookupfmt4_trans = gxv_bsln_LookupFmt4_transit;
185 gxv_LookupTable_validate( p + 2 * GXV_BSLN_VALUE_COUNT,
186 limit,
187 gxvalid );
188
189 GXV_EXIT;
190 }
191
192
193 static void
194 gxv_bsln_parts_fmt2_validate( FT_Bytes tables,
195 FT_Bytes limit,
196 GXV_Validator gxvalid )
197 {
198 FT_Bytes p = tables;
199
200 FT_UShort stdGlyph;
201 FT_UShort ctlPoint;
202 FT_Int i;
203
204 FT_UShort defaultBaseline = GXV_BSLN_DATA( defaultBaseline );
205
206
207 GXV_NAME_ENTER( "parts format 2" );
208
209 GXV_LIMIT_CHECK( 2 + ( 2 * GXV_BSLN_VALUE_COUNT ) );
210
211 /* stdGlyph */
212 stdGlyph = FT_NEXT_USHORT( p );
213 GXV_TRACE(( " (stdGlyph = %u)\n", stdGlyph ));
214
215 gxv_glyphid_validate( stdGlyph, gxvalid );
216
217 /* Record the position of ctlPoints */
218 GXV_BSLN_DATA( ctlPoints_p ) = p;
219
220 /* ctlPoints */
221 for ( i = 0; i < GXV_BSLN_VALUE_COUNT; i++ )
222 {
223 ctlPoint = FT_NEXT_USHORT( p );
224 if ( ctlPoint == GXV_BSLN_VALUE_EMPTY )
225 {
226 if ( i == defaultBaseline )
227 FT_INVALID_DATA;
228 }
229 else
230 gxv_ctlPoint_validate( stdGlyph, ctlPoint, gxvalid );
231 }
232
233 GXV_EXIT;
234 }
235
236
237 static void
238 gxv_bsln_parts_fmt3_validate( FT_Bytes tables,
239 FT_Bytes limit,
240 GXV_Validator gxvalid)
241 {
242 FT_Bytes p = tables;
243
244
245 GXV_NAME_ENTER( "parts format 3" );
246
247 /* stdGlyph + ctlPoints */
248 gxv_bsln_parts_fmt2_validate( p, limit, gxvalid );
249
250 /* mappingData */
251 gxvalid->lookupval_sign = GXV_LOOKUPVALUE_UNSIGNED;
252 gxvalid->lookupval_func = gxv_bsln_LookupValue_validate;
253 gxvalid->lookupfmt4_trans = gxv_bsln_LookupFmt4_transit;
254 gxv_LookupTable_validate( p + ( 2 + 2 * GXV_BSLN_VALUE_COUNT ),
255 limit,
256 gxvalid );
257
258 GXV_EXIT;
259 }
260
261
262 /*************************************************************************/
263 /*************************************************************************/
264 /***** *****/
265 /***** bsln TABLE *****/
266 /***** *****/
267 /*************************************************************************/
268 /*************************************************************************/
269
270 FT_LOCAL_DEF( void )
271 gxv_bsln_validate( FT_Bytes table,
272 FT_Face face,
273 FT_Validator ftvalid )
274 {
275 GXV_ValidatorRec gxvalidrec;
276 GXV_Validator gxvalid = &gxvalidrec;
277
278 GXV_bsln_DataRec bslnrec;
279 GXV_bsln_Data bsln = &bslnrec;
280
281 FT_Bytes p = table;
282 FT_Bytes limit = 0;
283
284 FT_ULong version;
285 FT_UShort format;
286 FT_UShort defaultBaseline;
287
288 GXV_Validate_Func fmt_funcs_table [] =
289 {
290 gxv_bsln_parts_fmt0_validate,
291 gxv_bsln_parts_fmt1_validate,
292 gxv_bsln_parts_fmt2_validate,
293 gxv_bsln_parts_fmt3_validate,
294 };
295
296
297 gxvalid->root = ftvalid;
298 gxvalid->table_data = bsln;
299 gxvalid->face = face;
300
301 FT_TRACE3(( "validating `bsln' table\n" ));
302 GXV_INIT;
303
304
305 GXV_LIMIT_CHECK( 4 + 2 + 2 );
306 version = FT_NEXT_ULONG( p );
307 format = FT_NEXT_USHORT( p );
308 defaultBaseline = FT_NEXT_USHORT( p );
309
310 /* only version 1.0 is defined (1996) */
311 if ( version != 0x00010000UL )
312 FT_INVALID_FORMAT;
313
314 /* only format 1, 2, 3 are defined (1996) */
315 GXV_TRACE(( " (format = %d)\n", format ));
316 if ( format > 3 )
317 FT_INVALID_FORMAT;
318
319 if ( defaultBaseline > 31 )
320 FT_INVALID_FORMAT;
321
322 bsln->defaultBaseline = defaultBaseline;
323
324 fmt_funcs_table[format]( p, limit, gxvalid );
325
326 FT_TRACE4(( "\n" ));
327 }
328
329
330 /* arch-tag: ebe81143-fdaa-4c68-a4d1-b57227daa3bc
331 (do not change this comment) */
332
333
334 /* END */