1
2 /* pngunknown.c - test the read side unknown chunk handling
3 *
4 * Last changed in libpng 1.6.32 [August 24, 2017]
5 * Copyright (c) 2015,2017 Glenn Randers-Pehrson
6 * Written by John Cunningham Bowler
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 * NOTES:
13 * This is a C program that is intended to be linked against libpng. It
14 * allows the libpng unknown handling code to be tested by interpreting
15 * arguments to save or discard combinations of chunks. The program is
16 * currently just a minimal validation for the built-in libpng facilities.
17 */
18
19 #include <stdlib.h>
20 #include <string.h>
21 #include <stdio.h>
22 #include <setjmp.h>
23
24 /* Define the following to use this test against your installed libpng, rather
25 * than the one being built here:
26 */
27 #ifdef PNG_FREESTANDING_TESTS
28 # include <png.h>
29 #else
30 # include "../../png.h"
31 #endif
32
33 /* 1.6.1 added support for the configure test harness, which uses 77 to indicate
34 * a skipped test, in earlier versions we need to succeed on a skipped test, so:
35 */
36 #if PNG_LIBPNG_VER >= 10601 && defined(HAVE_CONFIG_H)
37 # define SKIP 77
38 #else
39 # define SKIP 0
40 #endif
41
42
43 /* Since this program tests the ability to change the unknown chunk handling
44 * these must be defined:
45 */
46 #if defined(PNG_SET_UNKNOWN_CHUNKS_SUPPORTED) &&\
47 defined(PNG_STDIO_SUPPORTED) &&\
48 defined(PNG_READ_SUPPORTED)
49
50 /* One of these must be defined to allow us to find out what happened. It is
51 * still useful to set unknown chunk handling without either of these in order
52 * to cause *known* chunks to be discarded. This can be a significant
53 * efficiency gain, but it can't really be tested here.
54 */
55 #if defined(PNG_READ_USER_CHUNKS_SUPPORTED) ||\
56 defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
57
58 #if PNG_LIBPNG_VER < 10500
59 /* This deliberately lacks the const. */
60 typedef png_byte *png_const_bytep;
61
62 /* This is copied from 1.5.1 png.h: */
63 #define PNG_INTERLACE_ADAM7_PASSES 7
64 #define PNG_PASS_START_ROW(pass) (((1U&~(pass))<<(3-((pass)>>1)))&7)
65 #define PNG_PASS_START_COL(pass) (((1U& (pass))<<(3-(((pass)+1)>>1)))&7)
66 #define PNG_PASS_ROW_SHIFT(pass) ((pass)>2?(8-(pass))>>1:3)
67 #define PNG_PASS_COL_SHIFT(pass) ((pass)>1?(7-(pass))>>1:3)
68 #define PNG_PASS_ROWS(height, pass) (((height)+(((1<<PNG_PASS_ROW_SHIFT(pass))\
69 -1)-PNG_PASS_START_ROW(pass)))>>PNG_PASS_ROW_SHIFT(pass))
70 #define PNG_PASS_COLS(width, pass) (((width)+(((1<<PNG_PASS_COL_SHIFT(pass))\
71 -1)-PNG_PASS_START_COL(pass)))>>PNG_PASS_COL_SHIFT(pass))
72 #define PNG_ROW_FROM_PASS_ROW(yIn, pass) \
73 (((yIn)<<PNG_PASS_ROW_SHIFT(pass))+PNG_PASS_START_ROW(pass))
74 #define PNG_COL_FROM_PASS_COL(xIn, pass) \
75 (((xIn)<<PNG_PASS_COL_SHIFT(pass))+PNG_PASS_START_COL(pass))
76 #define PNG_PASS_MASK(pass,off) ( \
77 ((0x110145AFU>>(((7-(off))-(pass))<<2)) & 0xFU) | \
78 ((0x01145AF0U>>(((7-(off))-(pass))<<2)) & 0xF0U))
79 #define PNG_ROW_IN_INTERLACE_PASS(y, pass) \
80 ((PNG_PASS_MASK(pass,0) >> ((y)&7)) & 1)
81 #define PNG_COL_IN_INTERLACE_PASS(x, pass) \
82 ((PNG_PASS_MASK(pass,1) >> ((x)&7)) & 1)
83
84 /* These are needed too for the default build: */
85 #define PNG_WRITE_16BIT_SUPPORTED
86 #define PNG_READ_16BIT_SUPPORTED
87
88 /* This comes from pnglibconf.h after 1.5: */
89 #define PNG_FP_1 100000
90 #define PNG_GAMMA_THRESHOLD_FIXED\
91 ((png_fixed_point)(PNG_GAMMA_THRESHOLD * PNG_FP_1))
92 #endif
93
94 #if PNG_LIBPNG_VER < 10600
95 /* 1.6.0 constifies many APIs. The following exists to allow pngvalid to be
96 * compiled against earlier versions.
97 */
98 # define png_const_structp png_structp
99 #endif
100
101 #if PNG_LIBPNG_VER < 10700
102 /* Copied from libpng 1.7.0 png.h */
103 #define PNG_u2(b1, b2) (((unsigned int)(b1) << 8) + (b2))
104
105 #define PNG_U16(b1, b2) ((png_uint_16)PNG_u2(b1, b2))
106 #define PNG_U32(b1, b2, b3, b4)\
107 (((png_uint_32)PNG_u2(b1, b2) << 16) + PNG_u2(b3, b4))
108
109 /* Constants for known chunk types.
110 */
111 #define png_IDAT PNG_U32( 73, 68, 65, 84)
112 #define png_IEND PNG_U32( 73, 69, 78, 68)
113 #define png_IHDR PNG_U32( 73, 72, 68, 82)
114 #define png_PLTE PNG_U32( 80, 76, 84, 69)
115 #define png_bKGD PNG_U32( 98, 75, 71, 68)
116 #define png_cHRM PNG_U32( 99, 72, 82, 77)
117 #define png_eXIf PNG_U32(101, 88, 73, 102) /* registered July 2017 */
118 #define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */
119 #define png_gAMA PNG_U32(103, 65, 77, 65)
120 #define png_gIFg PNG_U32(103, 73, 70, 103)
121 #define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */
122 #define png_gIFx PNG_U32(103, 73, 70, 120)
123 #define png_hIST PNG_U32(104, 73, 83, 84)
124 #define png_iCCP PNG_U32(105, 67, 67, 80)
125 #define png_iTXt PNG_U32(105, 84, 88, 116)
126 #define png_oFFs PNG_U32(111, 70, 70, 115)
127 #define png_pCAL PNG_U32(112, 67, 65, 76)
128 #define png_pHYs PNG_U32(112, 72, 89, 115)
129 #define png_sBIT PNG_U32(115, 66, 73, 84)
130 #define png_sCAL PNG_U32(115, 67, 65, 76)
131 #define png_sPLT PNG_U32(115, 80, 76, 84)
132 #define png_sRGB PNG_U32(115, 82, 71, 66)
133 #define png_sTER PNG_U32(115, 84, 69, 82)
134 #define png_tEXt PNG_U32(116, 69, 88, 116)
135 #define png_tIME PNG_U32(116, 73, 77, 69)
136 #define png_tRNS PNG_U32(116, 82, 78, 83)
137 #define png_zTXt PNG_U32(122, 84, 88, 116)
138
139 /* Test on flag values as defined in the spec (section 5.4): */
140 #define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29))
141 #define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c))
142 #define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
143 #define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
144 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
145
146 #endif /* PNG_LIBPNG_VER < 10700 */
147
148 #ifdef __cplusplus
149 # define this not_the_cpp_this
150 # define new not_the_cpp_new
151 # define voidcast(type, value) static_cast<type>(value)
152 #else
153 # define voidcast(type, value) (value)
154 #endif /* __cplusplus */
155
156 /* Unused formal parameter errors are removed using the following macro which is
157 * expected to have no bad effects on performance.
158 */
159 #ifndef UNUSED
160 # if defined(__GNUC__) || defined(_MSC_VER)
161 # define UNUSED(param) (void)param;
162 # else
163 # define UNUSED(param)
164 # endif
165 #endif
166
167 /* Types of chunks not known to libpng */
168 #define png_vpAg PNG_U32(118, 112, 65, 103)
169
170 /* Chunk information */
171 #define PNG_INFO_tEXt 0x10000000U
172 #define PNG_INFO_iTXt 0x20000000U
173 #define PNG_INFO_zTXt 0x40000000U
174
175 #define PNG_INFO_sTER 0x01000000U
176 #define PNG_INFO_vpAg 0x02000000U
177
178 #define ABSENT 0
179 #define START 1
180 #define END 2
181
182 static struct
183 {
184 char name[5];
185 png_uint_32 flag;
186 png_uint_32 tag;
187 int unknown; /* Chunk not known to libpng */
188 int all; /* Chunk set by the '-1' option */
189 int position; /* position in pngtest.png */
190 int keep; /* unknown handling setting */
191 } chunk_info[] = {
192 /* Critical chunks */
193 { "IDAT", PNG_INFO_IDAT, png_IDAT, 0, 0, START, 0 }, /* must be [0] */
194 { "PLTE", PNG_INFO_PLTE, png_PLTE, 0, 0, ABSENT, 0 },
195
196 /* Non-critical chunks that libpng handles */
197 /* This is a mess but it seems to be the only way to do it - there is no way
198 * to check for a definition outside a #if.
199 */
200 { "bKGD", PNG_INFO_bKGD, png_bKGD,
201 # ifdef PNG_READ_bKGD_SUPPORTED
202 0,
203 # else
204 1,
205 # endif
206 1, START, 0 },
207 { "cHRM", PNG_INFO_cHRM, png_cHRM,
208 # ifdef PNG_READ_cHRM_SUPPORTED
209 0,
210 # else
211 1,
212 # endif
213 1, START, 0 },
214 { "eXIf", PNG_INFO_eXIf, png_eXIf,
215 # ifdef PNG_READ_eXIf_SUPPORTED
216 0,
217 # else
218 1,
219 # endif
220 1, END, 0 },
221 { "gAMA", PNG_INFO_gAMA, png_gAMA,
222 # ifdef PNG_READ_gAMA_SUPPORTED
223 0,
224 # else
225 1,
226 # endif
227 1, START, 0 },
228 { "hIST", PNG_INFO_hIST, png_hIST,
229 # ifdef PNG_READ_hIST_SUPPORTED
230 0,
231 # else
232 1,
233 # endif
234 1, ABSENT, 0 },
235 { "iCCP", PNG_INFO_iCCP, png_iCCP,
236 # ifdef PNG_READ_iCCP_SUPPORTED
237 0,
238 # else
239 1,
240 # endif
241 1, ABSENT, 0 },
242 { "iTXt", PNG_INFO_iTXt, png_iTXt,
243 # ifdef PNG_READ_iTXt_SUPPORTED
244 0,
245 # else
246 1,
247 # endif
248 1, ABSENT, 0 },
249 { "oFFs", PNG_INFO_oFFs, png_oFFs,
250 # ifdef PNG_READ_oFFs_SUPPORTED
251 0,
252 # else
253 1,
254 # endif
255 1, START, 0 },
256 { "pCAL", PNG_INFO_pCAL, png_pCAL,
257 # ifdef PNG_READ_pCAL_SUPPORTED
258 0,
259 # else
260 1,
261 # endif
262 1, START, 0 },
263 { "pHYs", PNG_INFO_pHYs, png_pHYs,
264 # ifdef PNG_READ_pHYs_SUPPORTED
265 0,
266 # else
267 1,
268 # endif
269 1, START, 0 },
270 { "sBIT", PNG_INFO_sBIT, png_sBIT,
271 # ifdef PNG_READ_sBIT_SUPPORTED
272 0,
273 # else
274 1,
275 # endif
276 1, START, 0 },
277 { "sCAL", PNG_INFO_sCAL, png_sCAL,
278 # ifdef PNG_READ_sCAL_SUPPORTED
279 0,
280 # else
281 1,
282 # endif
283 1, START, 0 },
284 { "sPLT", PNG_INFO_sPLT, png_sPLT,
285 # ifdef PNG_READ_sPLT_SUPPORTED
286 0,
287 # else
288 1,
289 # endif
290 1, ABSENT, 0 },
291 { "sRGB", PNG_INFO_sRGB, png_sRGB,
292 # ifdef PNG_READ_sRGB_SUPPORTED
293 0,
294 # else
295 1,
296 # endif
297 1, START, 0 },
298 { "tEXt", PNG_INFO_tEXt, png_tEXt,
299 # ifdef PNG_READ_tEXt_SUPPORTED
300 0,
301 # else
302 1,
303 # endif
304 1, START, 0 },
305 { "tIME", PNG_INFO_tIME, png_tIME,
306 # ifdef PNG_READ_tIME_SUPPORTED
307 0,
308 # else
309 1,
310 # endif
311 1, START, 0 },
312 { "tRNS", PNG_INFO_tRNS, png_tRNS,
313 # ifdef PNG_READ_tRNS_SUPPORTED
314 0,
315 # else
316 1,
317 # endif
318 0, ABSENT, 0 },
319 { "zTXt", PNG_INFO_zTXt, png_zTXt,
320 # ifdef PNG_READ_zTXt_SUPPORTED
321 0,
322 # else
323 1,
324 # endif
325 1, END, 0 },
326
327 /* No libpng handling */
328 { "sTER", PNG_INFO_sTER, png_sTER, 1, 1, START, 0 },
329 { "vpAg", PNG_INFO_vpAg, png_vpAg, 1, 0, START, 0 },
330 };
331
332 #define NINFO ((int)((sizeof chunk_info)/(sizeof chunk_info[0])))
333
334 static void
clear_keep(void)335 clear_keep(void)
336 {
337 int i = NINFO;
338 while (--i >= 0)
339 chunk_info[i].keep = 0;
340 }
341
342 static int
find(const char * name)343 find(const char *name)
344 {
345 int i = NINFO;
346 while (--i >= 0)
347 {
348 if (memcmp(chunk_info[i].name, name, 4) == 0)
349 break;
350 }
351
352 return i;
353 }
354
355 static int
findb(const png_byte * name)356 findb(const png_byte *name)
357 {
358 int i = NINFO;
359 while (--i >= 0)
360 {
361 if (memcmp(chunk_info[i].name, name, 4) == 0)
362 break;
363 }
364
365 return i;
366 }
367
368 static int
find_by_flag(png_uint_32 flag)369 find_by_flag(png_uint_32 flag)
370 {
371 int i = NINFO;
372
373 while (--i >= 0) if (chunk_info[i].flag == flag) return i;
374
375 fprintf(stderr, "pngunknown: internal error\n");
376 exit(4);
377 }
378
379 static int
ancillary(const char * name)380 ancillary(const char *name)
381 {
382 return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
383 }
384
385 #ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
386 static int
ancillaryb(const png_byte * name)387 ancillaryb(const png_byte *name)
388 {
389 return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
390 }
391 #endif
392
393 /* Type of an error_ptr */
394 typedef struct
395 {
396 jmp_buf error_return;
397 png_structp png_ptr;
398 png_infop info_ptr, end_ptr;
399 png_uint_32 before_IDAT;
400 png_uint_32 after_IDAT;
401 int error_count;
402 int warning_count;
403 int keep; /* the default value */
404 const char *program;
405 const char *file;
406 const char *test;
407 } display;
408
409 static const char init[] = "initialization";
410 static const char cmd[] = "command line";
411
412 static void
init_display(display * d,const char * program)413 init_display(display *d, const char *program)
414 {
415 memset(d, 0, sizeof *d);
416 d->png_ptr = NULL;
417 d->info_ptr = d->end_ptr = NULL;
418 d->error_count = d->warning_count = 0;
419 d->program = program;
420 d->file = program;
421 d->test = init;
422 }
423
424 static void
clean_display(display * d)425 clean_display(display *d)
426 {
427 png_destroy_read_struct(&d->png_ptr, &d->info_ptr, &d->end_ptr);
428
429 /* This must not happen - it might cause an app crash */
430 if (d->png_ptr != NULL || d->info_ptr != NULL || d->end_ptr != NULL)
431 {
432 fprintf(stderr, "%s(%s): png_destroy_read_struct error\n", d->file,
433 d->test);
434 exit(1);
435 }
436 }
437
438 PNG_FUNCTION(void, display_exit, (display *d), static PNG_NORETURN)
439 {
440 ++(d->error_count);
441
442 if (d->png_ptr != NULL)
443 clean_display(d);
444
445 /* During initialization and if this is a single command line argument set
446 * exit now - there is only one test, otherwise longjmp to do the next test.
447 */
448 if (d->test == init || d->test == cmd)
449 exit(1);
450
451 longjmp(d->error_return, 1);
452 }
453
454 static int
display_rc(const display * d,int strict)455 display_rc(const display *d, int strict)
456 {
457 return d->error_count + (strict ? d->warning_count : 0);
458 }
459
460 /* libpng error and warning callbacks */
461 PNG_FUNCTION(void, (PNGCBAPI error), (png_structp png_ptr, const char *message),
462 static PNG_NORETURN)
463 {
464 display *d = (display*)png_get_error_ptr(png_ptr);
465
466 fprintf(stderr, "%s(%s): libpng error: %s\n", d->file, d->test, message);
467 display_exit(d);
468 }
469
470 static void PNGCBAPI
warning(png_structp png_ptr,const char * message)471 warning(png_structp png_ptr, const char *message)
472 {
473 display *d = (display*)png_get_error_ptr(png_ptr);
474
475 fprintf(stderr, "%s(%s): libpng warning: %s\n", d->file, d->test, message);
476 ++(d->warning_count);
477 }
478
479 static png_uint_32
get_valid(display * d,png_infop info_ptr)480 get_valid(display *d, png_infop info_ptr)
481 {
482 png_uint_32 flags = png_get_valid(d->png_ptr, info_ptr, (png_uint_32)~0);
483
484 /* Map the text chunks back into the flags */
485 {
486 png_textp text;
487 png_uint_32 ntext = png_get_text(d->png_ptr, info_ptr, &text, NULL);
488
489 while (ntext > 0) switch (text[--ntext].compression)
490 {
491 case -1:
492 flags |= PNG_INFO_tEXt;
493 break;
494 case 0:
495 flags |= PNG_INFO_zTXt;
496 break;
497 case 1:
498 case 2:
499 flags |= PNG_INFO_iTXt;
500 break;
501 default:
502 fprintf(stderr, "%s(%s): unknown text compression %d\n", d->file,
503 d->test, text[ntext].compression);
504 display_exit(d);
505 }
506 }
507
508 return flags;
509 }
510
511 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
512 static int PNGCBAPI
read_callback(png_structp pp,png_unknown_chunkp pc)513 read_callback(png_structp pp, png_unknown_chunkp pc)
514 {
515 /* This function mimics the behavior of png_set_keep_unknown_chunks by
516 * returning '0' to keep the chunk and '1' to discard it.
517 */
518 display *d = voidcast(display*, png_get_user_chunk_ptr(pp));
519 int chunk = findb(pc->name);
520 int keep, discard;
521
522 if (chunk < 0) /* not one in our list, so not a known chunk */
523 keep = d->keep;
524
525 else
526 {
527 keep = chunk_info[chunk].keep;
528 if (keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
529 {
530 /* See the comments in png.h - use the default for unknown chunks,
531 * do not keep known chunks.
532 */
533 if (chunk_info[chunk].unknown)
534 keep = d->keep;
535
536 else
537 keep = PNG_HANDLE_CHUNK_NEVER;
538 }
539 }
540
541 switch (keep)
542 {
543 default:
544 fprintf(stderr, "%s(%s): %d: unrecognized chunk option\n", d->file,
545 d->test, chunk_info[chunk].keep);
546 display_exit(d);
547
548 case PNG_HANDLE_CHUNK_AS_DEFAULT:
549 case PNG_HANDLE_CHUNK_NEVER:
550 discard = 1/*handled; discard*/;
551 break;
552
553 case PNG_HANDLE_CHUNK_IF_SAFE:
554 case PNG_HANDLE_CHUNK_ALWAYS:
555 discard = 0/*not handled; keep*/;
556 break;
557 }
558
559 /* Also store information about this chunk in the display, the relevant flag
560 * is set if the chunk is to be kept ('not handled'.)
561 */
562 if (chunk >= 0) if (!discard) /* stupidity to stop a GCC warning */
563 {
564 png_uint_32 flag = chunk_info[chunk].flag;
565
566 if (pc->location & PNG_AFTER_IDAT)
567 d->after_IDAT |= flag;
568
569 else
570 d->before_IDAT |= flag;
571 }
572
573 /* However if there is no support to store unknown chunks don't ask libpng to
574 * do it; there will be an png_error.
575 */
576 # ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
577 return discard;
578 # else
579 return 1; /*handled; discard*/
580 # endif
581 }
582 #endif /* READ_USER_CHUNKS_SUPPORTED */
583
584 #ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
585 static png_uint_32
get_unknown(display * d,png_infop info_ptr,int after_IDAT)586 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
587 {
588 /* Create corresponding 'unknown' flags */
589 png_uint_32 flags = 0;
590
591 UNUSED(after_IDAT)
592
593 {
594 png_unknown_chunkp unknown;
595 int num_unknown = png_get_unknown_chunks(d->png_ptr, info_ptr, &unknown);
596
597 while (--num_unknown >= 0)
598 {
599 int chunk = findb(unknown[num_unknown].name);
600
601 /* Chunks not known to pngunknown must be validated here; since they
602 * must also be unknown to libpng the 'display->keep' behavior should
603 * have been used.
604 */
605 if (chunk < 0) switch (d->keep)
606 {
607 default: /* impossible */
608 case PNG_HANDLE_CHUNK_AS_DEFAULT:
609 case PNG_HANDLE_CHUNK_NEVER:
610 fprintf(stderr, "%s(%s): %s: %s: unknown chunk saved\n",
611 d->file, d->test, d->keep ? "discard" : "default",
612 unknown[num_unknown].name);
613 ++(d->error_count);
614 break;
615
616 case PNG_HANDLE_CHUNK_IF_SAFE:
617 if (!ancillaryb(unknown[num_unknown].name))
618 {
619 fprintf(stderr,
620 "%s(%s): if-safe: %s: unknown critical chunk saved\n",
621 d->file, d->test, unknown[num_unknown].name);
622 ++(d->error_count);
623 break;
624 }
625 /* FALLTHROUGH */ /* (safe) */
626 case PNG_HANDLE_CHUNK_ALWAYS:
627 break;
628 }
629
630 else
631 flags |= chunk_info[chunk].flag;
632 }
633 }
634
635 return flags;
636 }
637 #else /* SAVE_UNKNOWN_CHUNKS */
638 static png_uint_32
get_unknown(display * d,png_infop info_ptr,int after_IDAT)639 get_unknown(display *d, png_infop info_ptr, int after_IDAT)
640 /* Otherwise this will return the cached values set by any user callback */
641 {
642 UNUSED(info_ptr);
643
644 if (after_IDAT)
645 return d->after_IDAT;
646
647 else
648 return d->before_IDAT;
649 }
650
651 # ifndef PNG_READ_USER_CHUNKS_SUPPORTED
652 /* The #defines above should mean this is never reached, it's just here as
653 * a check to ensure the logic is correct.
654 */
655 # error No store support and no user chunk support, this will not work
656 # endif /* READ_USER_CHUNKS */
657 #endif /* SAVE_UNKNOWN_CHUNKS */
658
659 static int
check(FILE * fp,int argc,const char ** argv,png_uint_32p flags,display * d,int set_callback)660 check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
661 display *d, int set_callback)
662 {
663 int i, npasses, ipass;
664 png_uint_32 height;
665
666 d->keep = PNG_HANDLE_CHUNK_AS_DEFAULT;
667 d->before_IDAT = 0;
668 d->after_IDAT = 0;
669
670 /* Some of these errors are permanently fatal and cause an exit here, others
671 * are per-test and cause an error return.
672 */
673 d->png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, d, error,
674 warning);
675 if (d->png_ptr == NULL)
676 {
677 fprintf(stderr, "%s(%s): could not allocate png struct\n", d->file,
678 d->test);
679 /* Terminate here, this error is not test specific. */
680 exit(1);
681 }
682
683 d->info_ptr = png_create_info_struct(d->png_ptr);
684 d->end_ptr = png_create_info_struct(d->png_ptr);
685 if (d->info_ptr == NULL || d->end_ptr == NULL)
686 {
687 fprintf(stderr, "%s(%s): could not allocate png info\n", d->file,
688 d->test);
689 clean_display(d);
690 exit(1);
691 }
692
693 png_init_io(d->png_ptr, fp);
694
695 # ifdef PNG_READ_USER_CHUNKS_SUPPORTED
696 /* This is only done if requested by the caller; it interferes with the
697 * standard store/save mechanism.
698 */
699 if (set_callback)
700 png_set_read_user_chunk_fn(d->png_ptr, d, read_callback);
701 # else
702 UNUSED(set_callback)
703 # endif
704
705 /* Handle each argument in turn; multiple settings are possible for the same
706 * chunk and multiple calls will occur (the last one should override all
707 * preceding ones).
708 */
709 for (i=0; i<argc; ++i)
710 {
711 const char *equals = strchr(argv[i], '=');
712
713 if (equals != NULL)
714 {
715 int chunk, option;
716
717 if (strcmp(equals+1, "default") == 0)
718 option = PNG_HANDLE_CHUNK_AS_DEFAULT;
719 else if (strcmp(equals+1, "discard") == 0)
720 option = PNG_HANDLE_CHUNK_NEVER;
721 else if (strcmp(equals+1, "if-safe") == 0)
722 option = PNG_HANDLE_CHUNK_IF_SAFE;
723 else if (strcmp(equals+1, "save") == 0)
724 option = PNG_HANDLE_CHUNK_ALWAYS;
725 else
726 {
727 fprintf(stderr, "%s(%s): %s: unrecognized chunk option\n", d->file,
728 d->test, argv[i]);
729 display_exit(d);
730 }
731
732 switch (equals - argv[i])
733 {
734 case 4: /* chunk name */
735 chunk = find(argv[i]);
736
737 if (chunk >= 0)
738 {
739 /* These #if tests have the effect of skipping the arguments
740 * if SAVE support is unavailable - we can't do a useful test
741 * in this case, so we just check the arguments! This could
742 * be improved in the future by using the read callback.
743 */
744 # if PNG_LIBPNG_VER >= 10700 &&\
745 !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
746 if (option < PNG_HANDLE_CHUNK_IF_SAFE)
747 # endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
748 {
749 png_byte name[5];
750
751 memcpy(name, chunk_info[chunk].name, 5);
752 png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
753 chunk_info[chunk].keep = option;
754 }
755 continue;
756 }
757
758 break;
759
760 case 7: /* default */
761 if (memcmp(argv[i], "default", 7) == 0)
762 {
763 # if PNG_LIBPNG_VER >= 10700 &&\
764 !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
765 if (option < PNG_HANDLE_CHUNK_IF_SAFE)
766 # endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
767 png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
768
769 d->keep = option;
770 continue;
771 }
772
773 break;
774
775 case 3: /* all */
776 if (memcmp(argv[i], "all", 3) == 0)
777 {
778 # if PNG_LIBPNG_VER >= 10700 &&\
779 !defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
780 if (option < PNG_HANDLE_CHUNK_IF_SAFE)
781 # endif /* 1.7+ SAVE_UNKNOWN_CHUNKS */
782 png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
783
784 d->keep = option;
785
786 for (chunk = 0; chunk < NINFO; ++chunk)
787 if (chunk_info[chunk].all)
788 chunk_info[chunk].keep = option;
789 continue;
790 }
791
792 break;
793
794 default: /* some misplaced = */
795
796 break;
797 }
798 }
799
800 fprintf(stderr, "%s(%s): %s: unrecognized chunk argument\n", d->file,
801 d->test, argv[i]);
802 display_exit(d);
803 }
804
805 png_read_info(d->png_ptr, d->info_ptr);
806
807 switch (png_get_interlace_type(d->png_ptr, d->info_ptr))
808 {
809 case PNG_INTERLACE_NONE:
810 npasses = 1;
811 break;
812
813 case PNG_INTERLACE_ADAM7:
814 npasses = PNG_INTERLACE_ADAM7_PASSES;
815 break;
816
817 default:
818 /* Hard error because it is not test specific */
819 fprintf(stderr, "%s(%s): invalid interlace type\n", d->file, d->test);
820 clean_display(d);
821 exit(1);
822 }
823
824 /* Skip the image data, if IDAT is not being handled then don't do this
825 * because it will cause a CRC error.
826 */
827 if (chunk_info[0/*IDAT*/].keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
828 {
829 png_start_read_image(d->png_ptr);
830 height = png_get_image_height(d->png_ptr, d->info_ptr);
831
832 if (npasses > 1)
833 {
834 png_uint_32 width = png_get_image_width(d->png_ptr, d->info_ptr);
835
836 for (ipass=0; ipass<npasses; ++ipass)
837 {
838 png_uint_32 wPass = PNG_PASS_COLS(width, ipass);
839
840 if (wPass > 0)
841 {
842 png_uint_32 y;
843
844 for (y=0; y<height; ++y) if (PNG_ROW_IN_INTERLACE_PASS(y, ipass))
845 png_read_row(d->png_ptr, NULL, NULL);
846 }
847 }
848 } /* interlaced */
849
850 else /* not interlaced */
851 {
852 png_uint_32 y;
853
854 for (y=0; y<height; ++y)
855 png_read_row(d->png_ptr, NULL, NULL);
856 }
857 }
858
859 png_read_end(d->png_ptr, d->end_ptr);
860
861 flags[0] = get_valid(d, d->info_ptr);
862 flags[1] = get_unknown(d, d->info_ptr, 0/*before IDAT*/);
863
864 /* Only png_read_png sets PNG_INFO_IDAT! */
865 flags[chunk_info[0/*IDAT*/].keep != PNG_HANDLE_CHUNK_AS_DEFAULT] |=
866 PNG_INFO_IDAT;
867
868 flags[2] = get_valid(d, d->end_ptr);
869 flags[3] = get_unknown(d, d->end_ptr, 1/*after IDAT*/);
870
871 clean_display(d);
872
873 return d->keep;
874 }
875
876 static void
check_error(display * d,png_uint_32 flags,const char * message)877 check_error(display *d, png_uint_32 flags, const char *message)
878 {
879 while (flags)
880 {
881 png_uint_32 flag = flags & -(png_int_32)flags;
882 int i = find_by_flag(flag);
883
884 fprintf(stderr, "%s(%s): chunk %s: %s\n", d->file, d->test,
885 chunk_info[i].name, message);
886 ++(d->error_count);
887
888 flags &= ~flag;
889 }
890 }
891
892 static void
check_handling(display * d,int def,png_uint_32 chunks,png_uint_32 known,png_uint_32 unknown,const char * position,int set_callback)893 check_handling(display *d, int def, png_uint_32 chunks, png_uint_32 known,
894 png_uint_32 unknown, const char *position, int set_callback)
895 {
896 while (chunks)
897 {
898 png_uint_32 flag = chunks & -(png_int_32)chunks;
899 int i = find_by_flag(flag);
900 int keep = chunk_info[i].keep;
901 const char *type;
902 const char *errorx = NULL;
903
904 if (chunk_info[i].unknown)
905 {
906 if (keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
907 {
908 type = "UNKNOWN (default)";
909 keep = def;
910 }
911
912 else
913 type = "UNKNOWN (specified)";
914
915 if (flag & known)
916 errorx = "chunk processed";
917
918 else switch (keep)
919 {
920 case PNG_HANDLE_CHUNK_AS_DEFAULT:
921 if (flag & unknown)
922 errorx = "DEFAULT: unknown chunk saved";
923 break;
924
925 case PNG_HANDLE_CHUNK_NEVER:
926 if (flag & unknown)
927 errorx = "DISCARD: unknown chunk saved";
928 break;
929
930 case PNG_HANDLE_CHUNK_IF_SAFE:
931 if (ancillary(chunk_info[i].name))
932 {
933 if (!(flag & unknown))
934 errorx = "IF-SAFE: unknown ancillary chunk lost";
935 }
936
937 else if (flag & unknown)
938 errorx = "IF-SAFE: unknown critical chunk saved";
939 break;
940
941 case PNG_HANDLE_CHUNK_ALWAYS:
942 if (!(flag & unknown))
943 errorx = "SAVE: unknown chunk lost";
944 break;
945
946 default:
947 errorx = "internal error: bad keep";
948 break;
949 }
950 } /* unknown chunk */
951
952 else /* known chunk */
953 {
954 type = "KNOWN";
955
956 if (flag & known)
957 {
958 /* chunk was processed, it won't have been saved because that is
959 * caught below when checking for inconsistent processing.
960 */
961 if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
962 errorx = "!DEFAULT: known chunk processed";
963 }
964
965 else /* not processed */ switch (keep)
966 {
967 case PNG_HANDLE_CHUNK_AS_DEFAULT:
968 errorx = "DEFAULT: known chunk not processed";
969 break;
970
971 case PNG_HANDLE_CHUNK_NEVER:
972 if (flag & unknown)
973 errorx = "DISCARD: known chunk saved";
974 break;
975
976 case PNG_HANDLE_CHUNK_IF_SAFE:
977 if (ancillary(chunk_info[i].name))
978 {
979 if (!(flag & unknown))
980 errorx = "IF-SAFE: known ancillary chunk lost";
981 }
982
983 else if (flag & unknown)
984 errorx = "IF-SAFE: known critical chunk saved";
985 break;
986
987 case PNG_HANDLE_CHUNK_ALWAYS:
988 if (!(flag & unknown))
989 errorx = "SAVE: known chunk lost";
990 break;
991
992 default:
993 errorx = "internal error: bad keep (2)";
994 break;
995 }
996 }
997
998 if (errorx != NULL)
999 {
1000 ++(d->error_count);
1001 fprintf(stderr, "%s(%s%s): %s %s %s: %s\n", d->file, d->test,
1002 set_callback ? ",callback" : "",
1003 type, chunk_info[i].name, position, errorx);
1004 }
1005
1006 chunks &= ~flag;
1007 }
1008 }
1009
1010 static void
perform_one_test(FILE * fp,int argc,const char ** argv,png_uint_32 * default_flags,display * d,int set_callback)1011 perform_one_test(FILE *fp, int argc, const char **argv,
1012 png_uint_32 *default_flags, display *d, int set_callback)
1013 {
1014 int def;
1015 png_uint_32 flags[2][4];
1016
1017 rewind(fp);
1018 clear_keep();
1019 memcpy(flags[0], default_flags, sizeof flags[0]);
1020
1021 def = check(fp, argc, argv, flags[1], d, set_callback);
1022
1023 /* If IDAT is being handled as unknown the image read is skipped and all the
1024 * IDATs after the first end up in the end info struct, so in this case add
1025 * IDAT to the list of unknowns. (Do this after 'check' above sets the
1026 * chunk_info 'keep' fields.)
1027 *
1028 * Note that the flag setting has to be in the 'known' field to avoid
1029 * triggering the consistency check below and the flag must only be set if
1030 * there are multiple IDATs, so if the check above did find an unknown IDAT
1031 * after IDAT.
1032 */
1033 if (chunk_info[0/*IDAT*/].keep != PNG_HANDLE_CHUNK_AS_DEFAULT &&
1034 (flags[1][3] & PNG_INFO_IDAT) != 0)
1035 flags[0][2] |= PNG_INFO_IDAT;
1036
1037 /* Chunks should either be known or unknown, never both and this should apply
1038 * whether the chunk is before or after the IDAT (actually, the app can
1039 * probably change this by swapping the handling after the image, but this
1040 * test does not do that.)
1041 */
1042 check_error(d, (flags[0][0]|flags[0][2]) & (flags[0][1]|flags[0][3]),
1043 "chunk handled inconsistently in count tests");
1044 check_error(d, (flags[1][0]|flags[1][2]) & (flags[1][1]|flags[1][3]),
1045 "chunk handled inconsistently in option tests");
1046
1047 /* Now find out what happened to each chunk before and after the IDAT and
1048 * determine if the behavior was correct. First some basic sanity checks,
1049 * any known chunk should be known in the original count, any unknown chunk
1050 * should be either known or unknown in the original.
1051 */
1052 {
1053 png_uint_32 test;
1054
1055 test = flags[1][0] & ~flags[0][0];
1056 check_error(d, test, "new known chunk before IDAT");
1057 test = flags[1][1] & ~(flags[0][0] | flags[0][1]);
1058 check_error(d, test, "new unknown chunk before IDAT");
1059 test = flags[1][2] & ~flags[0][2];
1060 check_error(d, test, "new known chunk after IDAT");
1061 test = flags[1][3] & ~(flags[0][2] | flags[0][3]);
1062 check_error(d, test, "new unknown chunk after IDAT");
1063 }
1064
1065 /* Now each chunk in the original list should have been handled according to
1066 * the options set for that chunk, regardless of whether libpng knows about
1067 * it or not.
1068 */
1069 check_handling(d, def, flags[0][0] | flags[0][1], flags[1][0], flags[1][1],
1070 "before IDAT", set_callback);
1071 check_handling(d, def, flags[0][2] | flags[0][3], flags[1][2], flags[1][3],
1072 "after IDAT", set_callback);
1073 }
1074
1075 static void
perform_one_test_safe(FILE * fp,int argc,const char ** argv,png_uint_32 * default_flags,display * d,const char * test)1076 perform_one_test_safe(FILE *fp, int argc, const char **argv,
1077 png_uint_32 *default_flags, display *d, const char *test)
1078 {
1079 if (setjmp(d->error_return) == 0)
1080 {
1081 d->test = test; /* allow use of d->error_return */
1082 # ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
1083 perform_one_test(fp, argc, argv, default_flags, d, 0);
1084 # endif
1085 # ifdef PNG_READ_USER_CHUNKS_SUPPORTED
1086 perform_one_test(fp, argc, argv, default_flags, d, 1);
1087 # endif
1088 d->test = init; /* prevent use of d->error_return */
1089 }
1090 }
1091
1092 static const char *standard_tests[] =
1093 {
1094 "discard", "default=discard", 0,
1095 "save", "default=save", 0,
1096 "if-safe", "default=if-safe", 0,
1097 "vpAg", "vpAg=if-safe", 0,
1098 "sTER", "sTER=if-safe", 0,
1099 "IDAT", "default=discard", "IDAT=save", 0,
1100 "sAPI", "bKGD=save", "cHRM=save", "gAMA=save", "all=discard", "iCCP=save",
1101 "sBIT=save", "sRGB=save", "eXIf=save", 0,
1102 0/*end*/
1103 };
1104
1105 static PNG_NORETURN void
usage(const char * program,const char * reason)1106 usage(const char *program, const char *reason)
1107 {
1108 fprintf(stderr, "pngunknown: %s: usage:\n %s [--strict] "
1109 "--default|{(CHNK|default|all)=(default|discard|if-safe|save)} "
1110 "testfile.png\n", reason, program);
1111 exit(99);
1112 }
1113
1114 int
main(int argc,const char ** argv)1115 main(int argc, const char **argv)
1116 {
1117 FILE *fp;
1118 png_uint_32 default_flags[4/*valid,unknown{before,after}*/];
1119 int strict = 0, default_tests = 0;
1120 const char *count_argv = "default=save";
1121 const char *touch_file = NULL;
1122 display d;
1123
1124 init_display(&d, argv[0]);
1125
1126 while (++argv, --argc > 0)
1127 {
1128 if (strcmp(*argv, "--strict") == 0)
1129 strict = 1;
1130
1131 else if (strcmp(*argv, "--default") == 0)
1132 default_tests = 1;
1133
1134 else if (strcmp(*argv, "--touch") == 0)
1135 {
1136 if (argc > 1)
1137 touch_file = *++argv, --argc;
1138
1139 else
1140 usage(d.program, "--touch: missing file name");
1141 }
1142
1143 else
1144 break;
1145 }
1146
1147 /* A file name is required, but there should be no other arguments if
1148 * --default was specified.
1149 */
1150 if (argc <= 0)
1151 usage(d.program, "missing test file");
1152
1153 /* GCC BUG: if (default_tests && argc != 1) triggers some weird GCC argc
1154 * optimization which causes warnings with -Wstrict-overflow!
1155 */
1156 else if (default_tests) if (argc != 1)
1157 usage(d.program, "extra arguments");
1158
1159 /* The name of the test file is the last argument; remove it. */
1160 d.file = argv[--argc];
1161
1162 fp = fopen(d.file, "rb");
1163 if (fp == NULL)
1164 {
1165 perror(d.file);
1166 exit(99);
1167 }
1168
1169 /* First find all the chunks, known and unknown, in the test file, a failure
1170 * here aborts the whole test.
1171 *
1172 * If 'save' is supported then the normal saving method should happen,
1173 * otherwise if 'read' is supported then the read callback will do the
1174 * same thing. If both are supported the 'read' callback won't be
1175 * instantiated by default. If 'save' is *not* supported then a user
1176 * callback is required even though we can call png_get_unknown_chunks.
1177 */
1178 if (check(fp, 1, &count_argv, default_flags, &d,
1179 # ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
1180 0
1181 # else
1182 1
1183 # endif
1184 ) != PNG_HANDLE_CHUNK_ALWAYS)
1185 {
1186 fprintf(stderr, "%s: %s: internal error\n", d.program, d.file);
1187 exit(99);
1188 }
1189
1190 /* Now find what the various supplied options cause to change: */
1191 if (!default_tests)
1192 {
1193 d.test = cmd; /* acts as a flag to say exit, do not longjmp */
1194 # ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
1195 perform_one_test(fp, argc, argv, default_flags, &d, 0);
1196 # endif
1197 # ifdef PNG_READ_USER_CHUNKS_SUPPORTED
1198 perform_one_test(fp, argc, argv, default_flags, &d, 1);
1199 # endif
1200 d.test = init;
1201 }
1202
1203 else
1204 {
1205 const char **test = standard_tests;
1206
1207 /* Set the exit_test pointer here so we can continue after a libpng error.
1208 * NOTE: this leaks memory because the png_struct data from the failing
1209 * test is never freed.
1210 */
1211 while (*test)
1212 {
1213 const char *this_test = *test++;
1214 const char **next = test;
1215 int count = display_rc(&d, strict), new_count;
1216 const char *result;
1217 int arg_count = 0;
1218
1219 while (*next) ++next, ++arg_count;
1220
1221 perform_one_test_safe(fp, arg_count, test, default_flags, &d,
1222 this_test);
1223
1224 new_count = display_rc(&d, strict);
1225
1226 if (new_count == count)
1227 result = "PASS";
1228
1229 else
1230 result = "FAIL";
1231
1232 printf("%s: %s %s\n", result, d.program, this_test);
1233
1234 test = next+1;
1235 }
1236 }
1237
1238 fclose(fp);
1239
1240 if (display_rc(&d, strict) == 0)
1241 {
1242 /* Success, touch the success file if appropriate */
1243 if (touch_file != NULL)
1244 {
1245 FILE *fsuccess = fopen(touch_file, "wt");
1246
1247 if (fsuccess != NULL)
1248 {
1249 int err = 0;
1250 fprintf(fsuccess, "PNG unknown tests succeeded\n");
1251 fflush(fsuccess);
1252 err = ferror(fsuccess);
1253
1254 if (fclose(fsuccess) || err)
1255 {
1256 fprintf(stderr, "%s: write failed\n", touch_file);
1257 exit(99);
1258 }
1259 }
1260
1261 else
1262 {
1263 fprintf(stderr, "%s: open failed\n", touch_file);
1264 exit(99);
1265 }
1266 }
1267
1268 return 0;
1269 }
1270
1271 return 1;
1272 }
1273
1274 #else /* !(READ_USER_CHUNKS || SAVE_UNKNOWN_CHUNKS) */
1275 int
main(void)1276 main(void)
1277 {
1278 fprintf(stderr,
1279 " test ignored: no support to find out about unknown chunks\n");
1280 /* So the test is skipped: */
1281 return SKIP;
1282 }
1283 #endif /* READ_USER_CHUNKS || SAVE_UNKNOWN_CHUNKS */
1284
1285 #else /* !(SET_UNKNOWN_CHUNKS && READ) */
1286 int
main(void)1287 main(void)
1288 {
1289 fprintf(stderr,
1290 " test ignored: no support to modify unknown chunk handling\n");
1291 /* So the test is skipped: */
1292 return SKIP;
1293 }
1294 #endif /* SET_UNKNOWN_CHUNKS && READ*/
1295