1 /***************************************************************************/
2 /*                                                                         */
3 /*  gxvbsln.c                                                              */
4 /*                                                                         */
5 /*    TrueTypeGX/AAT bsln table validation (body).                         */
6 /*                                                                         */
7 /*  Copyright 2004, 2005 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 "gxvalid.h"
28 #include "gxvcommn.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_gxvbsln
39 
40 
41   /*************************************************************************/
42   /*************************************************************************/
43   /*****                                                               *****/
44   /*****                      Data and Types                           *****/
45   /*****                                                               *****/
46   /*************************************************************************/
47   /*************************************************************************/
48 
49 #define GXV_BSLN_VALUE_COUNT  32
50 #define GXV_BSLN_VALUE_EMPTY  0xFFFFU
51 
52 
53   typedef struct  GXV_bsln_DataRec_
54   {
55     FT_Bytes   ctlPoints_p;
56     FT_UShort  defaultBaseline;
57 
58   } GXV_bsln_DataRec, *GXV_bsln_Data;
59 
60 
61 #define GXV_BSLN_DATA( field )  GXV_TABLE_DATA( bsln, field )
62 
63 
64   /*************************************************************************/
65   /*************************************************************************/
66   /*****                                                               *****/
67   /*****                      UTILITY FUNCTIONS                        *****/
68   /*****                                                               *****/
69   /*************************************************************************/
70   /*************************************************************************/
71 
72   static void
gxv_bsln_LookupValue_validate(FT_UShort glyph,GXV_LookupValueCPtr value_p,GXV_Validator valid)73   gxv_bsln_LookupValue_validate( FT_UShort            glyph,
74                                  GXV_LookupValueCPtr  value_p,
75                                  GXV_Validator        valid )
76   {
77     FT_UShort   v = value_p->u;
78     FT_UShort*  ctlPoints;
79 
80     FT_UNUSED( glyph );
81 
82 
83     GXV_NAME_ENTER( "lookup value" );
84 
85     if ( v >= GXV_BSLN_VALUE_COUNT )
86       FT_INVALID_DATA;
87 
88     ctlPoints = (FT_UShort*)GXV_BSLN_DATA( ctlPoints_p );
89     if ( ctlPoints && ctlPoints[v] == GXV_BSLN_VALUE_EMPTY )
90       FT_INVALID_DATA;
91 
92     GXV_EXIT;
93   }
94 
95 
96   /*
97     +===============+ --------+
98     | lookup header |         |
99     +===============+         |
100     | BinSrchHeader |         |
101     +===============+         |
102     | lastGlyph[0]  |         |
103     +---------------+         |
104     | firstGlyph[0] |         |    head of lookup table
105     +---------------+         |             +
106     | offset[0]     |    ->   |          offset            [byte]
107     +===============+         |             +
108     | lastGlyph[1]  |         | (glyphID - firstGlyph) * 2 [byte]
109     +---------------+         |
110     | firstGlyph[1] |         |
111     +---------------+         |
112     | offset[1]     |         |
113     +===============+         |
114                               |
115     ...                       |
116                               |
117     16bit value array         |
118     +===============+         |
119     |     value     | <-------+
120     ...
121   */
122 
123   static GXV_LookupValueDesc
gxv_bsln_LookupFmt4_transit(FT_UShort relative_gindex,GXV_LookupValueCPtr base_value_p,FT_Bytes lookuptbl_limit,GXV_Validator valid)124   gxv_bsln_LookupFmt4_transit( FT_UShort            relative_gindex,
125                                GXV_LookupValueCPtr  base_value_p,
126                                FT_Bytes             lookuptbl_limit,
127                                GXV_Validator        valid )
128   {
129     FT_Bytes             p;
130     FT_Bytes             limit;
131     FT_UShort            offset;
132     GXV_LookupValueDesc  value;
133 
134     /* XXX: check range ? */
135     offset = (FT_UShort)( base_value_p->u +
136                           ( relative_gindex * sizeof ( FT_UShort ) ) );
137 
138     p     = valid->lookuptbl_head + offset;
139     limit = lookuptbl_limit;
140     GXV_LIMIT_CHECK( 2 );
141 
142     value.u = FT_NEXT_USHORT( p );
143 
144     return value;
145   }
146 
147 
148   static void
gxv_bsln_parts_fmt0_validate(FT_Bytes tables,FT_Bytes limit,GXV_Validator valid)149   gxv_bsln_parts_fmt0_validate( FT_Bytes       tables,
150                                 FT_Bytes       limit,
151                                 GXV_Validator  valid )
152   {
153     FT_Bytes  p = tables;
154 
155 
156     GXV_NAME_ENTER( "parts format 0" );
157 
158     /* deltas */
159     GXV_LIMIT_CHECK( 2 * GXV_BSLN_VALUE_COUNT );
160 
161     valid->table_data = NULL;      /* No ctlPoints here. */
162 
163     GXV_EXIT;
164   }
165 
166 
167   static void
gxv_bsln_parts_fmt1_validate(FT_Bytes tables,FT_Bytes limit,GXV_Validator valid)168   gxv_bsln_parts_fmt1_validate( FT_Bytes       tables,
169                                 FT_Bytes       limit,
170                                 GXV_Validator  valid )
171   {
172     FT_Bytes  p = tables;
173 
174 
175     GXV_NAME_ENTER( "parts format 1" );
176 
177     /* deltas */
178     gxv_bsln_parts_fmt0_validate( p, limit, valid );
179 
180     /* mappingData */
181     valid->lookupval_sign   = GXV_LOOKUPVALUE_UNSIGNED;
182     valid->lookupval_func   = gxv_bsln_LookupValue_validate;
183     valid->lookupfmt4_trans = gxv_bsln_LookupFmt4_transit;
184     gxv_LookupTable_validate( p + 2 * GXV_BSLN_VALUE_COUNT,
185                               limit,
186                               valid );
187 
188     GXV_EXIT;
189   }
190 
191 
192   static void
gxv_bsln_parts_fmt2_validate(FT_Bytes tables,FT_Bytes limit,GXV_Validator valid)193   gxv_bsln_parts_fmt2_validate( FT_Bytes       tables,
194                                 FT_Bytes       limit,
195                                 GXV_Validator  valid )
196   {
197     FT_Bytes   p = tables;
198 
199     FT_UShort  stdGlyph;
200     FT_UShort  ctlPoint;
201     FT_Int     i;
202 
203     FT_UShort  defaultBaseline = GXV_BSLN_DATA( defaultBaseline );
204 
205 
206     GXV_NAME_ENTER( "parts format 2" );
207 
208     GXV_LIMIT_CHECK( 2 + ( 2 * GXV_BSLN_VALUE_COUNT ) );
209 
210     /* stdGlyph */
211     stdGlyph = FT_NEXT_USHORT( p );
212     GXV_TRACE(( " (stdGlyph = %u)\n", stdGlyph ));
213 
214     gxv_glyphid_validate( stdGlyph, valid );
215 
216     /* Record the position of ctlPoints */
217     GXV_BSLN_DATA( ctlPoints_p ) = p;
218 
219     /* ctlPoints */
220     for ( i = 0; i < GXV_BSLN_VALUE_COUNT; i++ )
221     {
222       ctlPoint = FT_NEXT_USHORT( p );
223       if ( ctlPoint == GXV_BSLN_VALUE_EMPTY )
224       {
225         if ( i == defaultBaseline )
226           FT_INVALID_DATA;
227       }
228       else
229         gxv_ctlPoint_validate( stdGlyph, (FT_Short)ctlPoint, valid );
230     }
231 
232     GXV_EXIT;
233   }
234 
235 
236   static void
gxv_bsln_parts_fmt3_validate(FT_Bytes tables,FT_Bytes limit,GXV_Validator valid)237   gxv_bsln_parts_fmt3_validate( FT_Bytes       tables,
238                                 FT_Bytes       limit,
239                                 GXV_Validator  valid)
240   {
241     FT_Bytes  p = tables;
242 
243 
244     GXV_NAME_ENTER( "parts format 3" );
245 
246     /* stdGlyph + ctlPoints */
247     gxv_bsln_parts_fmt2_validate( p, limit, valid );
248 
249     /* mappingData */
250     valid->lookupval_sign   = GXV_LOOKUPVALUE_UNSIGNED;
251     valid->lookupval_func   = gxv_bsln_LookupValue_validate;
252     valid->lookupfmt4_trans = gxv_bsln_LookupFmt4_transit;
253     gxv_LookupTable_validate( p + ( 2 + 2 * GXV_BSLN_VALUE_COUNT ),
254                               limit,
255                               valid );
256 
257     GXV_EXIT;
258   }
259 
260 
261   /*************************************************************************/
262   /*************************************************************************/
263   /*****                                                               *****/
264   /*****                         bsln TABLE                            *****/
265   /*****                                                               *****/
266   /*************************************************************************/
267   /*************************************************************************/
268 
269   FT_LOCAL_DEF( void )
gxv_bsln_validate(FT_Bytes table,FT_Face face,FT_Validator ftvalid)270   gxv_bsln_validate( FT_Bytes      table,
271                      FT_Face       face,
272                      FT_Validator  ftvalid )
273   {
274     GXV_ValidatorRec  validrec;
275     GXV_Validator     valid = &validrec;
276 
277     GXV_bsln_DataRec  bslnrec;
278     GXV_bsln_Data     bsln = &bslnrec;
279 
280     FT_Bytes  p     = table;
281     FT_Bytes  limit = 0;
282 
283     FT_ULong   version;
284     FT_UShort  format;
285     FT_UShort  defaultBaseline;
286 
287     GXV_Validate_Func  fmt_funcs_table [] =
288     {
289       gxv_bsln_parts_fmt0_validate,
290       gxv_bsln_parts_fmt1_validate,
291       gxv_bsln_parts_fmt2_validate,
292       gxv_bsln_parts_fmt3_validate,
293     };
294 
295 
296     valid->root       = ftvalid;
297     valid->table_data = bsln;
298     valid->face       = face;
299 
300     FT_TRACE3(( "validating `bsln' table\n" ));
301     GXV_INIT;
302 
303 
304     GXV_LIMIT_CHECK( 4 + 2 + 2 );
305     version         = FT_NEXT_ULONG( p );
306     format          = FT_NEXT_USHORT( p );
307     defaultBaseline = FT_NEXT_USHORT( p );
308 
309     /* only version 1.0 is defined (1996) */
310     if ( version != 0x00010000UL )
311       FT_INVALID_FORMAT;
312 
313     /* only format 1, 2, 3 are defined (1996) */
314     GXV_TRACE(( " (format = %d)\n", format ));
315     if ( format > 3 )
316       FT_INVALID_FORMAT;
317 
318     if ( defaultBaseline > 31 )
319       FT_INVALID_FORMAT;
320 
321     bsln->defaultBaseline = defaultBaseline;
322 
323     fmt_funcs_table[format]( p, limit, valid );
324 
325     FT_TRACE4(( "\n" ));
326   }
327 
328 
329 /* arch-tag: ebe81143-fdaa-4c68-a4d1-b57227daa3bc
330    (do not change this comment) */
331 
332 
333 /* END */
334