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1 /* pngset.c - storage of image information into info struct
2  *
3  * Last changed in libpng 1.6.3 [July 18, 2013]
4  * Copyright (c) 1998-2013 Glenn Randers-Pehrson
5  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
6  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
7  *
8  * This code is released under the libpng license.
9  * For conditions of distribution and use, see the disclaimer
10  * and license in png.h
11  *
12  * The functions here are used during reads to store data from the file
13  * into the info struct, and during writes to store application data
14  * into the info struct for writing into the file.  This abstracts the
15  * info struct and allows us to change the structure in the future.
16  */
17 
18 #include "pngpriv.h"
19 
20 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
21 
22 #ifdef PNG_bKGD_SUPPORTED
23 void PNGAPI
png_set_bKGD(png_const_structrp png_ptr,png_inforp info_ptr,png_const_color_16p background)24 png_set_bKGD(png_const_structrp png_ptr, png_inforp info_ptr,
25     png_const_color_16p background)
26 {
27    png_debug1(1, "in %s storage function", "bKGD");
28 
29    if (png_ptr == NULL || info_ptr == NULL || background == NULL)
30       return;
31 
32    info_ptr->background = *background;
33    info_ptr->valid |= PNG_INFO_bKGD;
34 }
35 #endif
36 
37 #ifdef PNG_cHRM_SUPPORTED
38 void PNGFAPI
png_set_cHRM_fixed(png_const_structrp png_ptr,png_inforp info_ptr,png_fixed_point white_x,png_fixed_point white_y,png_fixed_point red_x,png_fixed_point red_y,png_fixed_point green_x,png_fixed_point green_y,png_fixed_point blue_x,png_fixed_point blue_y)39 png_set_cHRM_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
40     png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
41     png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
42     png_fixed_point blue_x, png_fixed_point blue_y)
43 {
44    png_xy xy;
45 
46    png_debug1(1, "in %s storage function", "cHRM fixed");
47 
48    if (png_ptr == NULL || info_ptr == NULL)
49       return;
50 
51    xy.redx = red_x;
52    xy.redy = red_y;
53    xy.greenx = green_x;
54    xy.greeny = green_y;
55    xy.bluex = blue_x;
56    xy.bluey = blue_y;
57    xy.whitex = white_x;
58    xy.whitey = white_y;
59 
60    if (png_colorspace_set_chromaticities(png_ptr, &info_ptr->colorspace, &xy,
61       2/* override with app values*/))
62       info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
63 
64    png_colorspace_sync_info(png_ptr, info_ptr);
65 }
66 
67 void PNGFAPI
png_set_cHRM_XYZ_fixed(png_const_structrp png_ptr,png_inforp info_ptr,png_fixed_point int_red_X,png_fixed_point int_red_Y,png_fixed_point int_red_Z,png_fixed_point int_green_X,png_fixed_point int_green_Y,png_fixed_point int_green_Z,png_fixed_point int_blue_X,png_fixed_point int_blue_Y,png_fixed_point int_blue_Z)68 png_set_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
69     png_fixed_point int_red_X, png_fixed_point int_red_Y,
70     png_fixed_point int_red_Z, png_fixed_point int_green_X,
71     png_fixed_point int_green_Y, png_fixed_point int_green_Z,
72     png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
73     png_fixed_point int_blue_Z)
74 {
75    png_XYZ XYZ;
76 
77    png_debug1(1, "in %s storage function", "cHRM XYZ fixed");
78 
79    if (png_ptr == NULL || info_ptr == NULL)
80       return;
81 
82    XYZ.red_X = int_red_X;
83    XYZ.red_Y = int_red_Y;
84    XYZ.red_Z = int_red_Z;
85    XYZ.green_X = int_green_X;
86    XYZ.green_Y = int_green_Y;
87    XYZ.green_Z = int_green_Z;
88    XYZ.blue_X = int_blue_X;
89    XYZ.blue_Y = int_blue_Y;
90    XYZ.blue_Z = int_blue_Z;
91 
92    if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace, &XYZ, 2))
93       info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
94 
95    png_colorspace_sync_info(png_ptr, info_ptr);
96 }
97 
98 #  ifdef PNG_FLOATING_POINT_SUPPORTED
99 void PNGAPI
png_set_cHRM(png_const_structrp png_ptr,png_inforp info_ptr,double white_x,double white_y,double red_x,double red_y,double green_x,double green_y,double blue_x,double blue_y)100 png_set_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
101     double white_x, double white_y, double red_x, double red_y,
102     double green_x, double green_y, double blue_x, double blue_y)
103 {
104    png_set_cHRM_fixed(png_ptr, info_ptr,
105       png_fixed(png_ptr, white_x, "cHRM White X"),
106       png_fixed(png_ptr, white_y, "cHRM White Y"),
107       png_fixed(png_ptr, red_x, "cHRM Red X"),
108       png_fixed(png_ptr, red_y, "cHRM Red Y"),
109       png_fixed(png_ptr, green_x, "cHRM Green X"),
110       png_fixed(png_ptr, green_y, "cHRM Green Y"),
111       png_fixed(png_ptr, blue_x, "cHRM Blue X"),
112       png_fixed(png_ptr, blue_y, "cHRM Blue Y"));
113 }
114 
115 void PNGAPI
png_set_cHRM_XYZ(png_const_structrp png_ptr,png_inforp info_ptr,double red_X,double red_Y,double red_Z,double green_X,double green_Y,double green_Z,double blue_X,double blue_Y,double blue_Z)116 png_set_cHRM_XYZ(png_const_structrp png_ptr, png_inforp info_ptr, double red_X,
117     double red_Y, double red_Z, double green_X, double green_Y, double green_Z,
118     double blue_X, double blue_Y, double blue_Z)
119 {
120    png_set_cHRM_XYZ_fixed(png_ptr, info_ptr,
121       png_fixed(png_ptr, red_X, "cHRM Red X"),
122       png_fixed(png_ptr, red_Y, "cHRM Red Y"),
123       png_fixed(png_ptr, red_Z, "cHRM Red Z"),
124       png_fixed(png_ptr, green_X, "cHRM Red X"),
125       png_fixed(png_ptr, green_Y, "cHRM Red Y"),
126       png_fixed(png_ptr, green_Z, "cHRM Red Z"),
127       png_fixed(png_ptr, blue_X, "cHRM Red X"),
128       png_fixed(png_ptr, blue_Y, "cHRM Red Y"),
129       png_fixed(png_ptr, blue_Z, "cHRM Red Z"));
130 }
131 #  endif /* PNG_FLOATING_POINT_SUPPORTED */
132 
133 #endif /* PNG_cHRM_SUPPORTED */
134 
135 #ifdef PNG_gAMA_SUPPORTED
136 void PNGFAPI
png_set_gAMA_fixed(png_const_structrp png_ptr,png_inforp info_ptr,png_fixed_point file_gamma)137 png_set_gAMA_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
138     png_fixed_point file_gamma)
139 {
140    png_debug1(1, "in %s storage function", "gAMA");
141 
142    if (png_ptr == NULL || info_ptr == NULL)
143       return;
144 
145    png_colorspace_set_gamma(png_ptr, &info_ptr->colorspace, file_gamma);
146    png_colorspace_sync_info(png_ptr, info_ptr);
147 }
148 
149 #  ifdef PNG_FLOATING_POINT_SUPPORTED
150 void PNGAPI
png_set_gAMA(png_const_structrp png_ptr,png_inforp info_ptr,double file_gamma)151 png_set_gAMA(png_const_structrp png_ptr, png_inforp info_ptr, double file_gamma)
152 {
153    png_set_gAMA_fixed(png_ptr, info_ptr, png_fixed(png_ptr, file_gamma,
154        "png_set_gAMA"));
155 }
156 #  endif
157 #endif
158 
159 #ifdef PNG_hIST_SUPPORTED
160 void PNGAPI
png_set_hIST(png_const_structrp png_ptr,png_inforp info_ptr,png_const_uint_16p hist)161 png_set_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
162     png_const_uint_16p hist)
163 {
164    int i;
165 
166    png_debug1(1, "in %s storage function", "hIST");
167 
168    if (png_ptr == NULL || info_ptr == NULL)
169       return;
170 
171    if (info_ptr->num_palette == 0 || info_ptr->num_palette
172        > PNG_MAX_PALETTE_LENGTH)
173    {
174       png_warning(png_ptr,
175           "Invalid palette size, hIST allocation skipped");
176 
177       return;
178    }
179 
180    png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
181 
182    /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in
183     * version 1.2.1
184     */
185    info_ptr->hist = png_voidcast(png_uint_16p, png_malloc_warn(png_ptr,
186        PNG_MAX_PALETTE_LENGTH * (sizeof (png_uint_16))));
187 
188    if (info_ptr->hist == NULL)
189    {
190       png_warning(png_ptr, "Insufficient memory for hIST chunk data");
191       return;
192    }
193 
194    info_ptr->free_me |= PNG_FREE_HIST;
195 
196    for (i = 0; i < info_ptr->num_palette; i++)
197       info_ptr->hist[i] = hist[i];
198 
199    info_ptr->valid |= PNG_INFO_hIST;
200 }
201 #endif
202 
203 void PNGAPI
png_set_IHDR(png_const_structrp png_ptr,png_inforp info_ptr,png_uint_32 width,png_uint_32 height,int bit_depth,int color_type,int interlace_type,int compression_type,int filter_type)204 png_set_IHDR(png_const_structrp png_ptr, png_inforp info_ptr,
205     png_uint_32 width, png_uint_32 height, int bit_depth,
206     int color_type, int interlace_type, int compression_type,
207     int filter_type)
208 {
209    png_debug1(1, "in %s storage function", "IHDR");
210 
211    if (png_ptr == NULL || info_ptr == NULL)
212       return;
213 
214    info_ptr->width = width;
215    info_ptr->height = height;
216    info_ptr->bit_depth = (png_byte)bit_depth;
217    info_ptr->color_type = (png_byte)color_type;
218    info_ptr->compression_type = (png_byte)compression_type;
219    info_ptr->filter_type = (png_byte)filter_type;
220    info_ptr->interlace_type = (png_byte)interlace_type;
221 
222    png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
223        info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
224        info_ptr->compression_type, info_ptr->filter_type);
225 
226    if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
227       info_ptr->channels = 1;
228 
229    else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
230       info_ptr->channels = 3;
231 
232    else
233       info_ptr->channels = 1;
234 
235    if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
236       info_ptr->channels++;
237 
238    info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
239 
240    info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
241 }
242 
243 #ifdef PNG_oFFs_SUPPORTED
244 void PNGAPI
png_set_oFFs(png_const_structrp png_ptr,png_inforp info_ptr,png_int_32 offset_x,png_int_32 offset_y,int unit_type)245 png_set_oFFs(png_const_structrp png_ptr, png_inforp info_ptr,
246     png_int_32 offset_x, png_int_32 offset_y, int unit_type)
247 {
248    png_debug1(1, "in %s storage function", "oFFs");
249 
250    if (png_ptr == NULL || info_ptr == NULL)
251       return;
252 
253    info_ptr->x_offset = offset_x;
254    info_ptr->y_offset = offset_y;
255    info_ptr->offset_unit_type = (png_byte)unit_type;
256    info_ptr->valid |= PNG_INFO_oFFs;
257 }
258 #endif
259 
260 #ifdef PNG_pCAL_SUPPORTED
261 void PNGAPI
png_set_pCAL(png_const_structrp png_ptr,png_inforp info_ptr,png_const_charp purpose,png_int_32 X0,png_int_32 X1,int type,int nparams,png_const_charp units,png_charpp params)262 png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
263     png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
264     int nparams, png_const_charp units, png_charpp params)
265 {
266    png_size_t length;
267    int i;
268 
269    png_debug1(1, "in %s storage function", "pCAL");
270 
271    if (png_ptr == NULL || info_ptr == NULL || purpose == NULL || units == NULL
272       || (nparams > 0 && params == NULL))
273       return;
274 
275    length = strlen(purpose) + 1;
276    png_debug1(3, "allocating purpose for info (%lu bytes)",
277        (unsigned long)length);
278 
279    /* TODO: validate format of calibration name and unit name */
280 
281    /* Check that the type matches the specification. */
282    if (type < 0 || type > 3)
283       png_error(png_ptr, "Invalid pCAL equation type");
284 
285    if (nparams < 0 || nparams > 255)
286       png_error(png_ptr, "Invalid pCAL parameter count");
287 
288    /* Validate params[nparams] */
289    for (i=0; i<nparams; ++i)
290       if (params[i] == NULL ||
291          !png_check_fp_string(params[i], strlen(params[i])))
292          png_error(png_ptr, "Invalid format for pCAL parameter");
293 
294    info_ptr->pcal_purpose = png_voidcast(png_charp,
295       png_malloc_warn(png_ptr, length));
296 
297    if (info_ptr->pcal_purpose == NULL)
298    {
299       png_warning(png_ptr, "Insufficient memory for pCAL purpose");
300       return;
301    }
302 
303    memcpy(info_ptr->pcal_purpose, purpose, length);
304 
305    png_debug(3, "storing X0, X1, type, and nparams in info");
306    info_ptr->pcal_X0 = X0;
307    info_ptr->pcal_X1 = X1;
308    info_ptr->pcal_type = (png_byte)type;
309    info_ptr->pcal_nparams = (png_byte)nparams;
310 
311    length = strlen(units) + 1;
312    png_debug1(3, "allocating units for info (%lu bytes)",
313      (unsigned long)length);
314 
315    info_ptr->pcal_units = png_voidcast(png_charp,
316       png_malloc_warn(png_ptr, length));
317 
318    if (info_ptr->pcal_units == NULL)
319    {
320       png_warning(png_ptr, "Insufficient memory for pCAL units");
321       return;
322    }
323 
324    memcpy(info_ptr->pcal_units, units, length);
325 
326    info_ptr->pcal_params = png_voidcast(png_charpp, png_malloc_warn(png_ptr,
327        (png_size_t)((nparams + 1) * (sizeof (png_charp)))));
328 
329    if (info_ptr->pcal_params == NULL)
330    {
331       png_warning(png_ptr, "Insufficient memory for pCAL params");
332       return;
333    }
334 
335    memset(info_ptr->pcal_params, 0, (nparams + 1) * (sizeof (png_charp)));
336 
337    for (i = 0; i < nparams; i++)
338    {
339       length = strlen(params[i]) + 1;
340       png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
341           (unsigned long)length);
342 
343       info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
344 
345       if (info_ptr->pcal_params[i] == NULL)
346       {
347          png_warning(png_ptr, "Insufficient memory for pCAL parameter");
348          return;
349       }
350 
351       memcpy(info_ptr->pcal_params[i], params[i], length);
352    }
353 
354    info_ptr->valid |= PNG_INFO_pCAL;
355    info_ptr->free_me |= PNG_FREE_PCAL;
356 }
357 #endif
358 
359 #ifdef PNG_sCAL_SUPPORTED
360 void PNGAPI
png_set_sCAL_s(png_const_structrp png_ptr,png_inforp info_ptr,int unit,png_const_charp swidth,png_const_charp sheight)361 png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
362     int unit, png_const_charp swidth, png_const_charp sheight)
363 {
364    png_size_t lengthw = 0, lengthh = 0;
365 
366    png_debug1(1, "in %s storage function", "sCAL");
367 
368    if (png_ptr == NULL || info_ptr == NULL)
369       return;
370 
371    /* Double check the unit (should never get here with an invalid
372     * unit unless this is an API call.)
373     */
374    if (unit != 1 && unit != 2)
375       png_error(png_ptr, "Invalid sCAL unit");
376 
377    if (swidth == NULL || (lengthw = strlen(swidth)) == 0 ||
378        swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
379       png_error(png_ptr, "Invalid sCAL width");
380 
381    if (sheight == NULL || (lengthh = strlen(sheight)) == 0 ||
382        sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
383       png_error(png_ptr, "Invalid sCAL height");
384 
385    info_ptr->scal_unit = (png_byte)unit;
386 
387    ++lengthw;
388 
389    png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);
390 
391    info_ptr->scal_s_width = png_voidcast(png_charp,
392       png_malloc_warn(png_ptr, lengthw));
393 
394    if (info_ptr->scal_s_width == NULL)
395    {
396       png_warning(png_ptr, "Memory allocation failed while processing sCAL");
397       return;
398    }
399 
400    memcpy(info_ptr->scal_s_width, swidth, lengthw);
401 
402    ++lengthh;
403 
404    png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);
405 
406    info_ptr->scal_s_height = png_voidcast(png_charp,
407       png_malloc_warn(png_ptr, lengthh));
408 
409    if (info_ptr->scal_s_height == NULL)
410    {
411       png_free (png_ptr, info_ptr->scal_s_width);
412       info_ptr->scal_s_width = NULL;
413 
414       png_warning(png_ptr, "Memory allocation failed while processing sCAL");
415       return;
416    }
417 
418    memcpy(info_ptr->scal_s_height, sheight, lengthh);
419 
420    info_ptr->valid |= PNG_INFO_sCAL;
421    info_ptr->free_me |= PNG_FREE_SCAL;
422 }
423 
424 #  ifdef PNG_FLOATING_POINT_SUPPORTED
425 void PNGAPI
png_set_sCAL(png_const_structrp png_ptr,png_inforp info_ptr,int unit,double width,double height)426 png_set_sCAL(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
427     double width, double height)
428 {
429    png_debug1(1, "in %s storage function", "sCAL");
430 
431    /* Check the arguments. */
432    if (width <= 0)
433       png_warning(png_ptr, "Invalid sCAL width ignored");
434 
435    else if (height <= 0)
436       png_warning(png_ptr, "Invalid sCAL height ignored");
437 
438    else
439    {
440       /* Convert 'width' and 'height' to ASCII. */
441       char swidth[PNG_sCAL_MAX_DIGITS+1];
442       char sheight[PNG_sCAL_MAX_DIGITS+1];
443 
444       png_ascii_from_fp(png_ptr, swidth, (sizeof swidth), width,
445          PNG_sCAL_PRECISION);
446       png_ascii_from_fp(png_ptr, sheight, (sizeof sheight), height,
447          PNG_sCAL_PRECISION);
448 
449       png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
450    }
451 }
452 #  endif
453 
454 #  ifdef PNG_FIXED_POINT_SUPPORTED
455 void PNGAPI
png_set_sCAL_fixed(png_const_structrp png_ptr,png_inforp info_ptr,int unit,png_fixed_point width,png_fixed_point height)456 png_set_sCAL_fixed(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
457     png_fixed_point width, png_fixed_point height)
458 {
459    png_debug1(1, "in %s storage function", "sCAL");
460 
461    /* Check the arguments. */
462    if (width <= 0)
463       png_warning(png_ptr, "Invalid sCAL width ignored");
464 
465    else if (height <= 0)
466       png_warning(png_ptr, "Invalid sCAL height ignored");
467 
468    else
469    {
470       /* Convert 'width' and 'height' to ASCII. */
471       char swidth[PNG_sCAL_MAX_DIGITS+1];
472       char sheight[PNG_sCAL_MAX_DIGITS+1];
473 
474       png_ascii_from_fixed(png_ptr, swidth, (sizeof swidth), width);
475       png_ascii_from_fixed(png_ptr, sheight, (sizeof sheight), height);
476 
477       png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
478    }
479 }
480 #  endif
481 #endif
482 
483 #ifdef PNG_pHYs_SUPPORTED
484 void PNGAPI
png_set_pHYs(png_const_structrp png_ptr,png_inforp info_ptr,png_uint_32 res_x,png_uint_32 res_y,int unit_type)485 png_set_pHYs(png_const_structrp png_ptr, png_inforp info_ptr,
486     png_uint_32 res_x, png_uint_32 res_y, int unit_type)
487 {
488    png_debug1(1, "in %s storage function", "pHYs");
489 
490    if (png_ptr == NULL || info_ptr == NULL)
491       return;
492 
493    info_ptr->x_pixels_per_unit = res_x;
494    info_ptr->y_pixels_per_unit = res_y;
495    info_ptr->phys_unit_type = (png_byte)unit_type;
496    info_ptr->valid |= PNG_INFO_pHYs;
497 }
498 #endif
499 
500 void PNGAPI
png_set_PLTE(png_structrp png_ptr,png_inforp info_ptr,png_const_colorp palette,int num_palette)501 png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
502     png_const_colorp palette, int num_palette)
503 {
504 
505    png_debug1(1, "in %s storage function", "PLTE");
506 
507    if (png_ptr == NULL || info_ptr == NULL)
508       return;
509 
510    if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
511    {
512       if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
513          png_error(png_ptr, "Invalid palette length");
514 
515       else
516       {
517          png_warning(png_ptr, "Invalid palette length");
518          return;
519       }
520    }
521 
522    if ((num_palette > 0 && palette == NULL) ||
523       (num_palette == 0
524 #        ifdef PNG_MNG_FEATURES_SUPPORTED
525             && (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0
526 #        endif
527       ))
528    {
529       png_chunk_report(png_ptr, "Invalid palette", PNG_CHUNK_ERROR);
530       return;
531    }
532 
533    /* It may not actually be necessary to set png_ptr->palette here;
534     * we do it for backward compatibility with the way the png_handle_tRNS
535     * function used to do the allocation.
536     *
537     * 1.6.0: the above statement appears to be incorrect; something has to set
538     * the palette inside png_struct on read.
539     */
540    png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
541 
542    /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
543     * of num_palette entries, in case of an invalid PNG file that has
544     * too-large sample values.
545     */
546    png_ptr->palette = png_voidcast(png_colorp, png_calloc(png_ptr,
547        PNG_MAX_PALETTE_LENGTH * (sizeof (png_color))));
548 
549    if (num_palette > 0)
550       memcpy(png_ptr->palette, palette, num_palette * (sizeof (png_color)));
551    info_ptr->palette = png_ptr->palette;
552    info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
553 
554    info_ptr->free_me |= PNG_FREE_PLTE;
555 
556    info_ptr->valid |= PNG_INFO_PLTE;
557 }
558 
559 #ifdef PNG_sBIT_SUPPORTED
560 void PNGAPI
png_set_sBIT(png_const_structrp png_ptr,png_inforp info_ptr,png_const_color_8p sig_bit)561 png_set_sBIT(png_const_structrp png_ptr, png_inforp info_ptr,
562     png_const_color_8p sig_bit)
563 {
564    png_debug1(1, "in %s storage function", "sBIT");
565 
566    if (png_ptr == NULL || info_ptr == NULL || sig_bit == NULL)
567       return;
568 
569    info_ptr->sig_bit = *sig_bit;
570    info_ptr->valid |= PNG_INFO_sBIT;
571 }
572 #endif
573 
574 #ifdef PNG_sRGB_SUPPORTED
575 void PNGAPI
png_set_sRGB(png_const_structrp png_ptr,png_inforp info_ptr,int srgb_intent)576 png_set_sRGB(png_const_structrp png_ptr, png_inforp info_ptr, int srgb_intent)
577 {
578    png_debug1(1, "in %s storage function", "sRGB");
579 
580    if (png_ptr == NULL || info_ptr == NULL)
581       return;
582 
583    (void)png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent);
584    png_colorspace_sync_info(png_ptr, info_ptr);
585 }
586 
587 void PNGAPI
png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr,png_inforp info_ptr,int srgb_intent)588 png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
589     int srgb_intent)
590 {
591    png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM");
592 
593    if (png_ptr == NULL || info_ptr == NULL)
594       return;
595 
596    if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent))
597    {
598       /* This causes the gAMA and cHRM to be written too */
599       info_ptr->colorspace.flags |=
600          PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
601    }
602 
603    png_colorspace_sync_info(png_ptr, info_ptr);
604 }
605 #endif /* sRGB */
606 
607 
608 #ifdef PNG_iCCP_SUPPORTED
609 void PNGAPI
png_set_iCCP(png_const_structrp png_ptr,png_inforp info_ptr,png_const_charp name,int compression_type,png_const_bytep profile,png_uint_32 proflen)610 png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
611     png_const_charp name, int compression_type,
612     png_const_bytep profile, png_uint_32 proflen)
613 {
614    png_charp new_iccp_name;
615    png_bytep new_iccp_profile;
616    png_size_t length;
617 
618    png_debug1(1, "in %s storage function", "iCCP");
619 
620    if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
621       return;
622 
623    if (compression_type != PNG_COMPRESSION_TYPE_BASE)
624       png_app_error(png_ptr, "Invalid iCCP compression method");
625 
626    /* Set the colorspace first because this validates the profile; do not
627     * override previously set app cHRM or gAMA here (because likely as not the
628     * application knows better than libpng what the correct values are.)  Pass
629     * the info_ptr color_type field to png_colorspace_set_ICC because in the
630     * write case it has not yet been stored in png_ptr.
631     */
632    {
633       int result = png_colorspace_set_ICC(png_ptr, &info_ptr->colorspace, name,
634          proflen, profile, info_ptr->color_type);
635 
636       png_colorspace_sync_info(png_ptr, info_ptr);
637 
638       /* Don't do any of the copying if the profile was bad, or inconsistent. */
639       if (!result)
640          return;
641 
642       /* But do write the gAMA and cHRM chunks from the profile. */
643       info_ptr->colorspace.flags |=
644          PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
645    }
646 
647    length = strlen(name)+1;
648    new_iccp_name = png_voidcast(png_charp, png_malloc_warn(png_ptr, length));
649 
650    if (new_iccp_name == NULL)
651    {
652       png_benign_error(png_ptr, "Insufficient memory to process iCCP chunk");
653       return;
654    }
655 
656    memcpy(new_iccp_name, name, length);
657    new_iccp_profile = png_voidcast(png_bytep,
658       png_malloc_warn(png_ptr, proflen));
659 
660    if (new_iccp_profile == NULL)
661    {
662       png_free(png_ptr, new_iccp_name);
663       png_benign_error(png_ptr,
664           "Insufficient memory to process iCCP profile");
665       return;
666    }
667 
668    memcpy(new_iccp_profile, profile, proflen);
669 
670    png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
671 
672    info_ptr->iccp_proflen = proflen;
673    info_ptr->iccp_name = new_iccp_name;
674    info_ptr->iccp_profile = new_iccp_profile;
675    info_ptr->free_me |= PNG_FREE_ICCP;
676    info_ptr->valid |= PNG_INFO_iCCP;
677 }
678 #endif
679 
680 #ifdef PNG_TEXT_SUPPORTED
681 void PNGAPI
png_set_text(png_const_structrp png_ptr,png_inforp info_ptr,png_const_textp text_ptr,int num_text)682 png_set_text(png_const_structrp png_ptr, png_inforp info_ptr,
683     png_const_textp text_ptr, int num_text)
684 {
685    int ret;
686    ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
687 
688    if (ret)
689       png_error(png_ptr, "Insufficient memory to store text");
690 }
691 
692 int /* PRIVATE */
png_set_text_2(png_const_structrp png_ptr,png_inforp info_ptr,png_const_textp text_ptr,int num_text)693 png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
694     png_const_textp text_ptr, int num_text)
695 {
696    int i;
697 
698    png_debug1(1, "in %lx storage function", png_ptr == NULL ? "unexpected" :
699       (unsigned long)png_ptr->chunk_name);
700 
701    if (png_ptr == NULL || info_ptr == NULL || num_text <= 0 || text_ptr == NULL)
702       return(0);
703 
704    /* Make sure we have enough space in the "text" array in info_struct
705     * to hold all of the incoming text_ptr objects.  This compare can't overflow
706     * because max_text >= num_text (anyway, subtract of two positive integers
707     * can't overflow in any case.)
708     */
709    if (num_text > info_ptr->max_text - info_ptr->num_text)
710    {
711       int old_num_text = info_ptr->num_text;
712       int max_text;
713       png_textp new_text = NULL;
714 
715       /* Calculate an appropriate max_text, checking for overflow. */
716       max_text = old_num_text;
717       if (num_text <= INT_MAX - max_text)
718       {
719          max_text += num_text;
720 
721          /* Round up to a multiple of 8 */
722          if (max_text < INT_MAX-8)
723             max_text = (max_text + 8) & ~0x7;
724 
725          else
726             max_text = INT_MAX;
727 
728          /* Now allocate a new array and copy the old members in, this does all
729           * the overflow checks.
730           */
731          new_text = png_voidcast(png_textp,png_realloc_array(png_ptr,
732             info_ptr->text, old_num_text, max_text-old_num_text,
733             sizeof *new_text));
734       }
735 
736       if (new_text == NULL)
737       {
738          png_chunk_report(png_ptr, "too many text chunks",
739             PNG_CHUNK_WRITE_ERROR);
740          return 1;
741       }
742 
743       png_free(png_ptr, info_ptr->text);
744 
745       info_ptr->text = new_text;
746       info_ptr->free_me |= PNG_FREE_TEXT;
747       info_ptr->max_text = max_text;
748       /* num_text is adjusted below as the entries are copied in */
749 
750       png_debug1(3, "allocated %d entries for info_ptr->text", max_text);
751    }
752 
753    for (i = 0; i < num_text; i++)
754    {
755       size_t text_length, key_len;
756       size_t lang_len, lang_key_len;
757       png_textp textp = &(info_ptr->text[info_ptr->num_text]);
758 
759       if (text_ptr[i].key == NULL)
760           continue;
761 
762       if (text_ptr[i].compression < PNG_TEXT_COMPRESSION_NONE ||
763           text_ptr[i].compression >= PNG_TEXT_COMPRESSION_LAST)
764       {
765          png_chunk_report(png_ptr, "text compression mode is out of range",
766             PNG_CHUNK_WRITE_ERROR);
767          continue;
768       }
769 
770       key_len = strlen(text_ptr[i].key);
771 
772       if (text_ptr[i].compression <= 0)
773       {
774          lang_len = 0;
775          lang_key_len = 0;
776       }
777 
778       else
779 #  ifdef PNG_iTXt_SUPPORTED
780       {
781          /* Set iTXt data */
782 
783          if (text_ptr[i].lang != NULL)
784             lang_len = strlen(text_ptr[i].lang);
785 
786          else
787             lang_len = 0;
788 
789          if (text_ptr[i].lang_key != NULL)
790             lang_key_len = strlen(text_ptr[i].lang_key);
791 
792          else
793             lang_key_len = 0;
794       }
795 #  else /* PNG_iTXt_SUPPORTED */
796       {
797          png_chunk_report(png_ptr, "iTXt chunk not supported",
798             PNG_CHUNK_WRITE_ERROR);
799          continue;
800       }
801 #  endif
802 
803       if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
804       {
805          text_length = 0;
806 #  ifdef PNG_iTXt_SUPPORTED
807          if (text_ptr[i].compression > 0)
808             textp->compression = PNG_ITXT_COMPRESSION_NONE;
809 
810          else
811 #  endif
812             textp->compression = PNG_TEXT_COMPRESSION_NONE;
813       }
814 
815       else
816       {
817          text_length = strlen(text_ptr[i].text);
818          textp->compression = text_ptr[i].compression;
819       }
820 
821       textp->key = png_voidcast(png_charp,png_malloc_base(png_ptr,
822           key_len + text_length + lang_len + lang_key_len + 4));
823 
824       if (textp->key == NULL)
825       {
826          png_chunk_report(png_ptr, "text chunk: out of memory",
827                PNG_CHUNK_WRITE_ERROR);
828          return 1;
829       }
830 
831       png_debug2(2, "Allocated %lu bytes at %p in png_set_text",
832           (unsigned long)(png_uint_32)
833           (key_len + lang_len + lang_key_len + text_length + 4),
834           textp->key);
835 
836       memcpy(textp->key, text_ptr[i].key, key_len);
837       *(textp->key + key_len) = '\0';
838 
839       if (text_ptr[i].compression > 0)
840       {
841          textp->lang = textp->key + key_len + 1;
842          memcpy(textp->lang, text_ptr[i].lang, lang_len);
843          *(textp->lang + lang_len) = '\0';
844          textp->lang_key = textp->lang + lang_len + 1;
845          memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
846          *(textp->lang_key + lang_key_len) = '\0';
847          textp->text = textp->lang_key + lang_key_len + 1;
848       }
849 
850       else
851       {
852          textp->lang=NULL;
853          textp->lang_key=NULL;
854          textp->text = textp->key + key_len + 1;
855       }
856 
857       if (text_length)
858          memcpy(textp->text, text_ptr[i].text, text_length);
859 
860       *(textp->text + text_length) = '\0';
861 
862 #  ifdef PNG_iTXt_SUPPORTED
863       if (textp->compression > 0)
864       {
865          textp->text_length = 0;
866          textp->itxt_length = text_length;
867       }
868 
869       else
870 #  endif
871       {
872          textp->text_length = text_length;
873          textp->itxt_length = 0;
874       }
875 
876       info_ptr->num_text++;
877       png_debug1(3, "transferred text chunk %d", info_ptr->num_text);
878    }
879 
880    return(0);
881 }
882 #endif
883 
884 #ifdef PNG_tIME_SUPPORTED
885 void PNGAPI
png_set_tIME(png_const_structrp png_ptr,png_inforp info_ptr,png_const_timep mod_time)886 png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
887     png_const_timep mod_time)
888 {
889    png_debug1(1, "in %s storage function", "tIME");
890 
891    if (png_ptr == NULL || info_ptr == NULL || mod_time == NULL ||
892        (png_ptr->mode & PNG_WROTE_tIME))
893       return;
894 
895    if (mod_time->month == 0   || mod_time->month > 12  ||
896        mod_time->day   == 0   || mod_time->day   > 31  ||
897        mod_time->hour  > 23   || mod_time->minute > 59 ||
898        mod_time->second > 60)
899    {
900       png_warning(png_ptr, "Ignoring invalid time value");
901       return;
902    }
903 
904    info_ptr->mod_time = *mod_time;
905    info_ptr->valid |= PNG_INFO_tIME;
906 }
907 #endif
908 
909 #ifdef PNG_tRNS_SUPPORTED
910 void PNGAPI
png_set_tRNS(png_structrp png_ptr,png_inforp info_ptr,png_const_bytep trans_alpha,int num_trans,png_const_color_16p trans_color)911 png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
912     png_const_bytep trans_alpha, int num_trans, png_const_color_16p trans_color)
913 {
914    png_debug1(1, "in %s storage function", "tRNS");
915 
916    if (png_ptr == NULL || info_ptr == NULL)
917       return;
918 
919    if (trans_alpha != NULL)
920    {
921        /* It may not actually be necessary to set png_ptr->trans_alpha here;
922         * we do it for backward compatibility with the way the png_handle_tRNS
923         * function used to do the allocation.
924         *
925         * 1.6.0: The above statement is incorrect; png_handle_tRNS effectively
926         * relies on png_set_tRNS storing the information in png_struct
927         * (otherwise it won't be there for the code in pngrtran.c).
928         */
929 
930        png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
931 
932        /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
933        png_ptr->trans_alpha = info_ptr->trans_alpha = png_voidcast(png_bytep,
934          png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
935 
936        if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
937           memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
938    }
939 
940    if (trans_color != NULL)
941    {
942       int sample_max = (1 << info_ptr->bit_depth);
943 
944       if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
945           trans_color->gray > sample_max) ||
946           (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
947           (trans_color->red > sample_max ||
948           trans_color->green > sample_max ||
949           trans_color->blue > sample_max)))
950          png_warning(png_ptr,
951             "tRNS chunk has out-of-range samples for bit_depth");
952 
953       info_ptr->trans_color = *trans_color;
954 
955       if (num_trans == 0)
956          num_trans = 1;
957    }
958 
959    info_ptr->num_trans = (png_uint_16)num_trans;
960 
961    if (num_trans != 0)
962    {
963       info_ptr->valid |= PNG_INFO_tRNS;
964       info_ptr->free_me |= PNG_FREE_TRNS;
965    }
966 }
967 #endif
968 
969 #ifdef PNG_sPLT_SUPPORTED
970 void PNGAPI
png_set_sPLT(png_const_structrp png_ptr,png_inforp info_ptr,png_const_sPLT_tp entries,int nentries)971 png_set_sPLT(png_const_structrp png_ptr,
972     png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)
973 /*
974  *  entries        - array of png_sPLT_t structures
975  *                   to be added to the list of palettes
976  *                   in the info structure.
977  *
978  *  nentries       - number of palette structures to be
979  *                   added.
980  */
981 {
982    png_sPLT_tp np;
983 
984    if (png_ptr == NULL || info_ptr == NULL || nentries <= 0 || entries == NULL)
985       return;
986 
987    /* Use the internal realloc function, which checks for all the possible
988     * overflows.  Notice that the parameters are (int) and (size_t)
989     */
990    np = png_voidcast(png_sPLT_tp,png_realloc_array(png_ptr,
991       info_ptr->splt_palettes, info_ptr->splt_palettes_num, nentries,
992       sizeof *np));
993 
994    if (np == NULL)
995    {
996       /* Out of memory or too many chunks */
997       png_chunk_report(png_ptr, "too many sPLT chunks", PNG_CHUNK_WRITE_ERROR);
998       return;
999    }
1000 
1001    png_free(png_ptr, info_ptr->splt_palettes);
1002    info_ptr->splt_palettes = np;
1003    info_ptr->free_me |= PNG_FREE_SPLT;
1004 
1005    np += info_ptr->splt_palettes_num;
1006 
1007    do
1008    {
1009       png_size_t length;
1010 
1011       /* Skip invalid input entries */
1012       if (entries->name == NULL || entries->entries == NULL)
1013       {
1014          /* png_handle_sPLT doesn't do this, so this is an app error */
1015          png_app_error(png_ptr, "png_set_sPLT: invalid sPLT");
1016          /* Just skip the invalid entry */
1017          continue;
1018       }
1019 
1020       np->depth = entries->depth;
1021 
1022       /* In the even of out-of-memory just return - there's no point keeping on
1023        * trying to add sPLT chunks.
1024        */
1025       length = strlen(entries->name) + 1;
1026       np->name = png_voidcast(png_charp, png_malloc_base(png_ptr, length));
1027 
1028       if (np->name == NULL)
1029          break;
1030 
1031       memcpy(np->name, entries->name, length);
1032 
1033       /* IMPORTANT: we have memory now that won't get freed if something else
1034        * goes wrong, this code must free it.  png_malloc_array produces no
1035        * warnings, use a png_chunk_report (below) if there is an error.
1036        */
1037       np->entries = png_voidcast(png_sPLT_entryp, png_malloc_array(png_ptr,
1038           entries->nentries, sizeof (png_sPLT_entry)));
1039 
1040       if (np->entries == NULL)
1041       {
1042          png_free(png_ptr, np->name);
1043          break;
1044       }
1045 
1046       np->nentries = entries->nentries;
1047       /* This multiply can't overflow because png_malloc_array has already
1048        * checked it when doing the allocation.
1049        */
1050       memcpy(np->entries, entries->entries,
1051          entries->nentries * sizeof (png_sPLT_entry));
1052 
1053       /* Note that 'continue' skips the advance of the out pointer and out
1054        * count, so an invalid entry is not added.
1055        */
1056       info_ptr->valid |= PNG_INFO_sPLT;
1057       ++(info_ptr->splt_palettes_num);
1058       ++np;
1059    }
1060    while (++entries, --nentries);
1061 
1062    if (nentries > 0)
1063       png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR);
1064 }
1065 #endif /* PNG_sPLT_SUPPORTED */
1066 
1067 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
1068 static png_byte
check_location(png_const_structrp png_ptr,int location)1069 check_location(png_const_structrp png_ptr, int location)
1070 {
1071    location &= (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT);
1072 
1073    /* New in 1.6.0; copy the location and check it.  This is an API
1074     * change, previously the app had to use the
1075     * png_set_unknown_chunk_location API below for each chunk.
1076     */
1077    if (location == 0 && !(png_ptr->mode & PNG_IS_READ_STRUCT))
1078    {
1079       /* Write struct, so unknown chunks come from the app */
1080       png_app_warning(png_ptr,
1081          "png_set_unknown_chunks now expects a valid location");
1082       /* Use the old behavior */
1083       location = (png_byte)(png_ptr->mode &
1084          (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT));
1085    }
1086 
1087    /* This need not be an internal error - if the app calls
1088     * png_set_unknown_chunks on a read pointer it must get the location right.
1089     */
1090    if (location == 0)
1091       png_error(png_ptr, "invalid location in png_set_unknown_chunks");
1092 
1093    /* Now reduce the location to the top-most set bit by removing each least
1094     * significant bit in turn.
1095     */
1096    while (location != (location & -location))
1097       location &= ~(location & -location);
1098 
1099    /* The cast is safe because 'location' is a bit mask and only the low four
1100     * bits are significant.
1101     */
1102    return (png_byte)location;
1103 }
1104 
1105 void PNGAPI
png_set_unknown_chunks(png_const_structrp png_ptr,png_inforp info_ptr,png_const_unknown_chunkp unknowns,int num_unknowns)1106 png_set_unknown_chunks(png_const_structrp png_ptr,
1107    png_inforp info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns)
1108 {
1109    png_unknown_chunkp np;
1110 
1111    if (png_ptr == NULL || info_ptr == NULL || num_unknowns <= 0 ||
1112       unknowns == NULL)
1113       return;
1114 
1115    /* Check for the failure cases where support has been disabled at compile
1116     * time.  This code is hardly ever compiled - it's here because
1117     * STORE_UNKNOWN_CHUNKS is set by both read and write code (compiling in this
1118     * code) but may be meaningless if the read or write handling of unknown
1119     * chunks is not compiled in.
1120     */
1121 #  if !defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
1122       defined(PNG_READ_SUPPORTED)
1123       if (png_ptr->mode & PNG_IS_READ_STRUCT)
1124       {
1125          png_app_error(png_ptr, "no unknown chunk support on read");
1126          return;
1127       }
1128 #  endif
1129 #  if !defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
1130       defined(PNG_WRITE_SUPPORTED)
1131       if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
1132       {
1133          png_app_error(png_ptr, "no unknown chunk support on write");
1134          return;
1135       }
1136 #  endif
1137 
1138    /* Prior to 1.6.0 this code used png_malloc_warn; however, this meant that
1139     * unknown critical chunks could be lost with just a warning resulting in
1140     * undefined behavior.  Now png_chunk_report is used to provide behavior
1141     * appropriate to read or write.
1142     */
1143    np = png_voidcast(png_unknown_chunkp, png_realloc_array(png_ptr,
1144          info_ptr->unknown_chunks, info_ptr->unknown_chunks_num, num_unknowns,
1145          sizeof *np));
1146 
1147    if (np == NULL)
1148    {
1149       png_chunk_report(png_ptr, "too many unknown chunks",
1150          PNG_CHUNK_WRITE_ERROR);
1151       return;
1152    }
1153 
1154    png_free(png_ptr, info_ptr->unknown_chunks);
1155    info_ptr->unknown_chunks = np; /* safe because it is initialized */
1156    info_ptr->free_me |= PNG_FREE_UNKN;
1157 
1158    np += info_ptr->unknown_chunks_num;
1159 
1160    /* Increment unknown_chunks_num each time round the loop to protect the
1161     * just-allocated chunk data.
1162     */
1163    for (; num_unknowns > 0; --num_unknowns, ++unknowns)
1164    {
1165       memcpy(np->name, unknowns->name, (sizeof np->name));
1166       np->name[(sizeof np->name)-1] = '\0';
1167       np->location = check_location(png_ptr, unknowns->location);
1168 
1169       if (unknowns->size == 0)
1170       {
1171          np->data = NULL;
1172          np->size = 0;
1173       }
1174 
1175       else
1176       {
1177          np->data = png_voidcast(png_bytep,
1178             png_malloc_base(png_ptr, unknowns->size));
1179 
1180          if (np->data == NULL)
1181          {
1182             png_chunk_report(png_ptr, "unknown chunk: out of memory",
1183                PNG_CHUNK_WRITE_ERROR);
1184             /* But just skip storing the unknown chunk */
1185             continue;
1186          }
1187 
1188          memcpy(np->data, unknowns->data, unknowns->size);
1189          np->size = unknowns->size;
1190       }
1191 
1192       /* These increments are skipped on out-of-memory for the data - the
1193        * unknown chunk entry gets overwritten if the png_chunk_report returns.
1194        * This is correct in the read case (the chunk is just dropped.)
1195        */
1196       ++np;
1197       ++(info_ptr->unknown_chunks_num);
1198    }
1199 }
1200 
1201 void PNGAPI
png_set_unknown_chunk_location(png_const_structrp png_ptr,png_inforp info_ptr,int chunk,int location)1202 png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
1203     int chunk, int location)
1204 {
1205    /* This API is pretty pointless in 1.6.0 because the location can be set
1206     * before the call to png_set_unknown_chunks.
1207     *
1208     * TODO: add a png_app_warning in 1.7
1209     */
1210    if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 &&
1211       chunk < info_ptr->unknown_chunks_num)
1212    {
1213       if ((location & (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT)) == 0)
1214       {
1215          png_app_error(png_ptr, "invalid unknown chunk location");
1216          /* Fake out the pre 1.6.0 behavior: */
1217          if ((location & PNG_HAVE_IDAT)) /* undocumented! */
1218             location = PNG_AFTER_IDAT;
1219 
1220          else
1221             location = PNG_HAVE_IHDR; /* also undocumented */
1222       }
1223 
1224       info_ptr->unknown_chunks[chunk].location =
1225          check_location(png_ptr, location);
1226    }
1227 }
1228 #endif
1229 
1230 
1231 #ifdef PNG_MNG_FEATURES_SUPPORTED
1232 png_uint_32 PNGAPI
png_permit_mng_features(png_structrp png_ptr,png_uint_32 mng_features)1233 png_permit_mng_features (png_structrp png_ptr, png_uint_32 mng_features)
1234 {
1235    png_debug(1, "in png_permit_mng_features");
1236 
1237    if (png_ptr == NULL)
1238       return 0;
1239 
1240    png_ptr->mng_features_permitted = mng_features & PNG_ALL_MNG_FEATURES;
1241 
1242    return png_ptr->mng_features_permitted;
1243 }
1244 #endif
1245 
1246 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
1247 static unsigned int
add_one_chunk(png_bytep list,unsigned int count,png_const_bytep add,int keep)1248 add_one_chunk(png_bytep list, unsigned int count, png_const_bytep add, int keep)
1249 {
1250    unsigned int i;
1251 
1252    /* Utility function: update the 'keep' state of a chunk if it is already in
1253     * the list, otherwise add it to the list.
1254     */
1255    for (i=0; i<count; ++i, list += 5) if (memcmp(list, add, 4) == 0)
1256    {
1257       list[4] = (png_byte)keep;
1258       return count;
1259    }
1260 
1261    if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
1262    {
1263       ++count;
1264       memcpy(list, add, 4);
1265       list[4] = (png_byte)keep;
1266    }
1267 
1268    return count;
1269 }
1270 
1271 void PNGAPI
png_set_keep_unknown_chunks(png_structrp png_ptr,int keep,png_const_bytep chunk_list,int num_chunks_in)1272 png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
1273     png_const_bytep chunk_list, int num_chunks_in)
1274 {
1275    png_bytep new_list;
1276    unsigned int num_chunks, old_num_chunks;
1277 
1278    if (png_ptr == NULL)
1279       return;
1280 
1281    if (keep < 0 || keep >= PNG_HANDLE_CHUNK_LAST)
1282    {
1283       png_app_error(png_ptr, "png_set_keep_unknown_chunks: invalid keep");
1284       return;
1285    }
1286 
1287    if (num_chunks_in <= 0)
1288    {
1289       png_ptr->unknown_default = keep;
1290 
1291       /* '0' means just set the flags, so stop here */
1292       if (num_chunks_in == 0)
1293         return;
1294    }
1295 
1296    if (num_chunks_in < 0)
1297    {
1298       /* Ignore all unknown chunks and all chunks recognized by
1299        * libpng except for IHDR, PLTE, tRNS, IDAT, and IEND
1300        */
1301       static PNG_CONST png_byte chunks_to_ignore[] = {
1302          98,  75,  71,  68, '\0',  /* bKGD */
1303          99,  72,  82,  77, '\0',  /* cHRM */
1304         103,  65,  77,  65, '\0',  /* gAMA */
1305         104,  73,  83,  84, '\0',  /* hIST */
1306         105,  67,  67,  80, '\0',  /* iCCP */
1307         105,  84,  88, 116, '\0',  /* iTXt */
1308         111,  70,  70, 115, '\0',  /* oFFs */
1309         112,  67,  65,  76, '\0',  /* pCAL */
1310         112,  72,  89, 115, '\0',  /* pHYs */
1311         115,  66,  73,  84, '\0',  /* sBIT */
1312         115,  67,  65,  76, '\0',  /* sCAL */
1313         115,  80,  76,  84, '\0',  /* sPLT */
1314         115,  84,  69,  82, '\0',  /* sTER */
1315         115,  82,  71,  66, '\0',  /* sRGB */
1316         116,  69,  88, 116, '\0',  /* tEXt */
1317         116,  73,  77,  69, '\0',  /* tIME */
1318         122,  84,  88, 116, '\0'   /* zTXt */
1319       };
1320 
1321       chunk_list = chunks_to_ignore;
1322       num_chunks = (sizeof chunks_to_ignore)/5;
1323    }
1324 
1325    else /* num_chunks_in > 0 */
1326    {
1327       if (chunk_list == NULL)
1328       {
1329          /* Prior to 1.6.0 this was silently ignored, now it is an app_error
1330           * which can be switched off.
1331           */
1332          png_app_error(png_ptr, "png_set_keep_unknown_chunks: no chunk list");
1333          return;
1334       }
1335 
1336       num_chunks = num_chunks_in;
1337    }
1338 
1339    old_num_chunks = png_ptr->num_chunk_list;
1340    if (png_ptr->chunk_list == NULL)
1341       old_num_chunks = 0;
1342 
1343    /* Since num_chunks is always restricted to UINT_MAX/5 this can't overflow.
1344     */
1345    if (num_chunks + old_num_chunks > UINT_MAX/5)
1346    {
1347       png_app_error(png_ptr, "png_set_keep_unknown_chunks: too many chunks");
1348       return;
1349    }
1350 
1351    /* If these chunks are being reset to the default then no more memory is
1352     * required because add_one_chunk above doesn't extend the list if the 'keep'
1353     * parameter is the default.
1354     */
1355    if (keep)
1356    {
1357       new_list = png_voidcast(png_bytep, png_malloc(png_ptr,
1358           5 * (num_chunks + old_num_chunks)));
1359 
1360       if (old_num_chunks > 0)
1361          memcpy(new_list, png_ptr->chunk_list, 5*old_num_chunks);
1362    }
1363 
1364    else if (old_num_chunks > 0)
1365       new_list = png_ptr->chunk_list;
1366 
1367    else
1368       new_list = NULL;
1369 
1370    /* Add the new chunks together with each one's handling code.  If the chunk
1371     * already exists the code is updated, otherwise the chunk is added to the
1372     * end.  (In libpng 1.6.0 order no longer matters because this code enforces
1373     * the earlier convention that the last setting is the one that is used.)
1374     */
1375    if (new_list != NULL)
1376    {
1377       png_const_bytep inlist;
1378       png_bytep outlist;
1379       unsigned int i;
1380 
1381       for (i=0; i<num_chunks; ++i)
1382          old_num_chunks = add_one_chunk(new_list, old_num_chunks,
1383             chunk_list+5*i, keep);
1384 
1385       /* Now remove any spurious 'default' entries. */
1386       num_chunks = 0;
1387       for (i=0, inlist=outlist=new_list; i<old_num_chunks; ++i, inlist += 5)
1388          if (inlist[4])
1389          {
1390             if (outlist != inlist)
1391                memcpy(outlist, inlist, 5);
1392             outlist += 5;
1393             ++num_chunks;
1394          }
1395 
1396       /* This means the application has removed all the specialized handling. */
1397       if (num_chunks == 0)
1398       {
1399          if (png_ptr->chunk_list != new_list)
1400             png_free(png_ptr, new_list);
1401 
1402          new_list = NULL;
1403       }
1404    }
1405 
1406    else
1407       num_chunks = 0;
1408 
1409    png_ptr->num_chunk_list = num_chunks;
1410 
1411    if (png_ptr->chunk_list != new_list)
1412    {
1413       if (png_ptr->chunk_list != NULL)
1414          png_free(png_ptr, png_ptr->chunk_list);
1415 
1416       png_ptr->chunk_list = new_list;
1417    }
1418 }
1419 #endif
1420 
1421 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
1422 void PNGAPI
png_set_read_user_chunk_fn(png_structrp png_ptr,png_voidp user_chunk_ptr,png_user_chunk_ptr read_user_chunk_fn)1423 png_set_read_user_chunk_fn(png_structrp png_ptr, png_voidp user_chunk_ptr,
1424     png_user_chunk_ptr read_user_chunk_fn)
1425 {
1426    png_debug(1, "in png_set_read_user_chunk_fn");
1427 
1428    if (png_ptr == NULL)
1429       return;
1430 
1431    png_ptr->read_user_chunk_fn = read_user_chunk_fn;
1432    png_ptr->user_chunk_ptr = user_chunk_ptr;
1433 }
1434 #endif
1435 
1436 #ifdef PNG_INFO_IMAGE_SUPPORTED
1437 void PNGAPI
png_set_rows(png_const_structrp png_ptr,png_inforp info_ptr,png_bytepp row_pointers)1438 png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
1439     png_bytepp row_pointers)
1440 {
1441    png_debug1(1, "in %s storage function", "rows");
1442 
1443    if (png_ptr == NULL || info_ptr == NULL)
1444       return;
1445 
1446    if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
1447       png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
1448 
1449    info_ptr->row_pointers = row_pointers;
1450 
1451    if (row_pointers)
1452       info_ptr->valid |= PNG_INFO_IDAT;
1453 }
1454 #endif
1455 
1456 void PNGAPI
png_set_compression_buffer_size(png_structrp png_ptr,png_size_t size)1457 png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
1458 {
1459     if (png_ptr == NULL)
1460        return;
1461 
1462     if (size == 0 || size > PNG_UINT_31_MAX)
1463        png_error(png_ptr, "invalid compression buffer size");
1464 
1465 #  ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1466       if (png_ptr->mode & PNG_IS_READ_STRUCT)
1467       {
1468          png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
1469          return;
1470       }
1471 #  endif
1472 
1473 #  ifdef PNG_WRITE_SUPPORTED
1474       if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
1475       {
1476          if (png_ptr->zowner != 0)
1477          {
1478             png_warning(png_ptr,
1479               "Compression buffer size cannot be changed because it is in use");
1480             return;
1481          }
1482 
1483          if (size > ZLIB_IO_MAX)
1484          {
1485             png_warning(png_ptr,
1486                "Compression buffer size limited to system maximum");
1487             size = ZLIB_IO_MAX; /* must fit */
1488          }
1489 
1490          else if (size < 6)
1491          {
1492             /* Deflate will potentially go into an infinite loop on a SYNC_FLUSH
1493              * if this is permitted.
1494              */
1495             png_warning(png_ptr,
1496                "Compression buffer size cannot be reduced below 6");
1497             return;
1498          }
1499 
1500          if (png_ptr->zbuffer_size != size)
1501          {
1502             png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
1503             png_ptr->zbuffer_size = (uInt)size;
1504          }
1505       }
1506 #  endif
1507 }
1508 
1509 void PNGAPI
png_set_invalid(png_const_structrp png_ptr,png_inforp info_ptr,int mask)1510 png_set_invalid(png_const_structrp png_ptr, png_inforp info_ptr, int mask)
1511 {
1512    if (png_ptr && info_ptr)
1513       info_ptr->valid &= ~mask;
1514 }
1515 
1516 
1517 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
1518 /* This function was added to libpng 1.2.6 */
1519 void PNGAPI
png_set_user_limits(png_structrp png_ptr,png_uint_32 user_width_max,png_uint_32 user_height_max)1520 png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
1521     png_uint_32 user_height_max)
1522 {
1523    /* Images with dimensions larger than these limits will be
1524     * rejected by png_set_IHDR().  To accept any PNG datastream
1525     * regardless of dimensions, set both limits to 0x7ffffffL.
1526     */
1527    if (png_ptr == NULL)
1528       return;
1529 
1530    png_ptr->user_width_max = user_width_max;
1531    png_ptr->user_height_max = user_height_max;
1532 }
1533 
1534 /* This function was added to libpng 1.4.0 */
1535 void PNGAPI
png_set_chunk_cache_max(png_structrp png_ptr,png_uint_32 user_chunk_cache_max)1536 png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
1537 {
1538     if (png_ptr)
1539        png_ptr->user_chunk_cache_max = user_chunk_cache_max;
1540 }
1541 
1542 /* This function was added to libpng 1.4.1 */
1543 void PNGAPI
png_set_chunk_malloc_max(png_structrp png_ptr,png_alloc_size_t user_chunk_malloc_max)1544 png_set_chunk_malloc_max (png_structrp png_ptr,
1545     png_alloc_size_t user_chunk_malloc_max)
1546 {
1547    if (png_ptr)
1548       png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
1549 }
1550 #endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
1551 
1552 
1553 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
1554 void PNGAPI
png_set_benign_errors(png_structrp png_ptr,int allowed)1555 png_set_benign_errors(png_structrp png_ptr, int allowed)
1556 {
1557    png_debug(1, "in png_set_benign_errors");
1558 
1559    /* If allowed is 1, png_benign_error() is treated as a warning.
1560     *
1561     * If allowed is 0, png_benign_error() is treated as an error (which
1562     * is the default behavior if png_set_benign_errors() is not called).
1563     */
1564 
1565    if (allowed)
1566       png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN |
1567          PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN;
1568 
1569    else
1570       png_ptr->flags &= ~(PNG_FLAG_BENIGN_ERRORS_WARN |
1571          PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN);
1572 }
1573 #endif /* PNG_BENIGN_ERRORS_SUPPORTED */
1574 
1575 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
1576    /* Whether to report invalid palette index; added at libng-1.5.10.
1577     * It is possible for an indexed (color-type==3) PNG file to contain
1578     * pixels with invalid (out-of-range) indexes if the PLTE chunk has
1579     * fewer entries than the image's bit-depth would allow. We recover
1580     * from this gracefully by filling any incomplete palette with zeroes
1581     * (opaque black).  By default, when this occurs libpng will issue
1582     * a benign error.  This API can be used to override that behavior.
1583     */
1584 void PNGAPI
png_set_check_for_invalid_index(png_structrp png_ptr,int allowed)1585 png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
1586 {
1587    png_debug(1, "in png_set_check_for_invalid_index");
1588 
1589    if (allowed > 0)
1590       png_ptr->num_palette_max = 0;
1591 
1592    else
1593       png_ptr->num_palette_max = -1;
1594 }
1595 #endif
1596 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
1597