MagickCore  7.0.10
signature.c
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1 /*
2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 % %
4 % %
5 % SSSSS IIIII GGGG N N AAA TTTTT U U RRRR EEEEE %
6 % SS I G NN N A A T U U R R E %
7 % SSS I G GG N N N AAAAA T U U RRRR EEE %
8 % SS I G G N NN A A T U U R R E %
9 % SSSSS IIIII GGG N N A A T UUU R R EEEEE %
10 % %
11 % %
12 % MagickCore Methods to Compute a Message Digest for an Image %
13 % %
14 % Software Design %
15 % Cristy %
16 % December 1992 %
17 % %
18 % %
19 % Copyright 1999-2020 ImageMagick Studio LLC, a non-profit organization %
20 % dedicated to making software imaging solutions freely available. %
21 % %
22 % You may not use this file except in compliance with the License. You may %
23 % obtain a copy of the License at %
24 % %
25 % https://imagemagick.org/script/license.php %
26 % %
27 % Unless required by applicable law or agreed to in writing, software %
28 % distributed under the License is distributed on an "AS IS" BASIS, %
29 % WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %
30 % See the License for the specific language governing permissions and %
31 % limitations under the License. %
32 % %
33 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
34 %
35 %
36 %
37 */
38 
39 /*
40  Include declarations.
41 */
42 #include "MagickCore/studio.h"
43 #include "MagickCore/cache.h"
44 #include "MagickCore/exception.h"
45 #include "MagickCore/exception-private.h"
46 #include "MagickCore/property.h"
47 #include "MagickCore/image.h"
48 #include "MagickCore/memory_.h"
49 #include "MagickCore/memory-private.h"
50 #include "MagickCore/pixel-accessor.h"
51 #include "MagickCore/quantum.h"
52 #include "MagickCore/quantum-private.h"
53 #include "MagickCore/signature.h"
54 #include "MagickCore/signature-private.h"
55 #include "MagickCore/string_.h"
56 #include "MagickCore/timer-private.h"
57 /*
58  Define declarations.
59 */
60 #define SignatureBlocksize 64
61 #define SignatureDigestsize 32
62 
63 /*
64  Typedef declarations.
65 */
66 struct _SignatureInfo
67 {
68  unsigned int
69  digestsize,
70  blocksize;
71 
72  StringInfo
73  *digest,
74  *message;
75 
76  unsigned int
77  *accumulator,
78  low_order,
79  high_order;
80 
81  size_t
82  extent;
83 
84  MagickBooleanType
85  lsb_first;
86 
87  ssize_t
88  timestamp;
89 
90  size_t
91  signature;
92 };
93 
94 /*
95  Forward declarations.
96 */
97 static void
98  TransformSignature(SignatureInfo *);
99 
100 /*
101 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
102 % %
103 % %
104 % %
105 + A c q u i r e S i g n a t u r e I n f o %
106 % %
107 % %
108 % %
109 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
110 %
111 % AcquireSignatureInfo() allocate the SignatureInfo structure.
112 %
113 % The format of the AcquireSignatureInfo method is:
114 %
115 % SignatureInfo *AcquireSignatureInfo(void)
116 %
117 */
118 MagickPrivate SignatureInfo *AcquireSignatureInfo(void)
119 {
120  SignatureInfo
121  *signature_info;
122 
123  unsigned long
124  lsb_first;
125 
126  signature_info=(SignatureInfo *) AcquireCriticalMemory(
127  sizeof(*signature_info));
128  (void) memset(signature_info,0,sizeof(*signature_info));
129  signature_info->digestsize=SignatureDigestsize;
130  signature_info->blocksize=SignatureBlocksize;
131  signature_info->digest=AcquireStringInfo(SignatureDigestsize);
132  signature_info->message=AcquireStringInfo(SignatureBlocksize);
133  signature_info->accumulator=(unsigned int *) AcquireQuantumMemory(
134  SignatureBlocksize,sizeof(*signature_info->accumulator));
135  if (signature_info->accumulator == (unsigned int *) NULL)
136  ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
137  (void) memset(signature_info->accumulator,0,SignatureBlocksize*
138  sizeof(*signature_info->accumulator));
139  lsb_first=1;
140  signature_info->lsb_first=(int) (*(char *) &lsb_first) == 1 ? MagickTrue :
141  MagickFalse;
142  signature_info->timestamp=(ssize_t) GetMagickTime();
143  signature_info->signature=MagickCoreSignature;
144  InitializeSignature(signature_info);
145  return(signature_info);
146 }
147 
148 /*
149 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
150 % %
151 % %
152 % %
153 + D e s t r o y S i g n a t u r e I n f o %
154 % %
155 % %
156 % %
157 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
158 %
159 % DestroySignatureInfo() zeros memory associated with the SignatureInfo
160 % structure.
161 %
162 % The format of the DestroySignatureInfo method is:
163 %
164 % SignatureInfo *DestroySignatureInfo(SignatureInfo *signature_info)
165 %
166 % A description of each parameter follows:
167 %
168 % o signature_info: the cipher signature_info.
169 %
170 */
171 MagickPrivate SignatureInfo *DestroySignatureInfo(SignatureInfo *signature_info)
172 {
173  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
174  assert(signature_info != (SignatureInfo *) NULL);
175  assert(signature_info->signature == MagickCoreSignature);
176  if (signature_info->accumulator != (unsigned int *) NULL)
177  signature_info->accumulator=(unsigned int *) RelinquishMagickMemory(
178  signature_info->accumulator);
179  if (signature_info->message != (StringInfo *) NULL)
180  signature_info->message=DestroyStringInfo(signature_info->message);
181  if (signature_info->digest != (StringInfo *) NULL)
182  signature_info->digest=DestroyStringInfo(signature_info->digest);
183  signature_info->signature=(~MagickCoreSignature);
184  signature_info=(SignatureInfo *) RelinquishMagickMemory(signature_info);
185  return(signature_info);
186 }
187 
188 /*
189 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
190 % %
191 % %
192 % %
193 + F i n a l i z e S i g n a t u r e %
194 % %
195 % %
196 % %
197 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
198 %
199 % FinalizeSignature() finalizes the Signature message accumulator computation.
200 %
201 % The format of the FinalizeSignature method is:
202 %
203 % FinalizeSignature(SignatureInfo *signature_info)
204 %
205 % A description of each parameter follows:
206 %
207 % o signature_info: the address of a structure of type SignatureInfo.
208 %
209 */
210 MagickPrivate void FinalizeSignature(SignatureInfo *signature_info)
211 {
212  register ssize_t
213  i;
214 
215  register unsigned char
216  *q;
217 
218  register unsigned int
219  *p;
220 
221  size_t
222  extent;
223 
224  unsigned char
225  *datum;
226 
227  unsigned int
228  high_order,
229  low_order;
230 
231  /*
232  Add padding and return the message accumulator.
233  */
234  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
235  assert(signature_info != (SignatureInfo *) NULL);
236  assert(signature_info->signature == MagickCoreSignature);
237  low_order=signature_info->low_order;
238  high_order=signature_info->high_order;
239  extent=((low_order >> 3) & 0x3f);
240  datum=GetStringInfoDatum(signature_info->message);
241  datum[extent++]=(unsigned char) 0x80;
242  if (extent <= (unsigned int) (GetStringInfoLength(signature_info->message)-8))
243  (void) memset(datum+extent,0,GetStringInfoLength(
244  signature_info->message)-8-extent);
245  else
246  {
247  (void) memset(datum+extent,0,GetStringInfoLength(
248  signature_info->message)-extent);
249  TransformSignature(signature_info);
250  (void) memset(datum,0,GetStringInfoLength(
251  signature_info->message)-8);
252  }
253  datum[56]=(unsigned char) (high_order >> 24);
254  datum[57]=(unsigned char) (high_order >> 16);
255  datum[58]=(unsigned char) (high_order >> 8);
256  datum[59]=(unsigned char) high_order;
257  datum[60]=(unsigned char) (low_order >> 24);
258  datum[61]=(unsigned char) (low_order >> 16);
259  datum[62]=(unsigned char) (low_order >> 8);
260  datum[63]=(unsigned char) low_order;
261  TransformSignature(signature_info);
262  p=signature_info->accumulator;
263  q=GetStringInfoDatum(signature_info->digest);
264  for (i=0; i < (SignatureDigestsize/4); i++)
265  {
266  *q++=(unsigned char) ((*p >> 24) & 0xff);
267  *q++=(unsigned char) ((*p >> 16) & 0xff);
268  *q++=(unsigned char) ((*p >> 8) & 0xff);
269  *q++=(unsigned char) (*p & 0xff);
270  p++;
271  }
272 }
273 
274 /*
275 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
276 % %
277 % %
278 % %
279 + G e t S i g n a t u r e B l o c k s i z e %
280 % %
281 % %
282 % %
283 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
284 %
285 % GetSignatureBlocksize() returns the Signature blocksize.
286 %
287 % The format of the GetSignatureBlocksize method is:
288 %
289 % unsigned int *GetSignatureBlocksize(const SignatureInfo *signature_info)
290 %
291 % A description of each parameter follows:
292 %
293 % o signature_info: the signature info.
294 %
295 */
296 MagickPrivate unsigned int GetSignatureBlocksize(
297  const SignatureInfo *signature_info)
298 {
299  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
300  assert(signature_info != (SignatureInfo *) NULL);
301  assert(signature_info->signature == MagickCoreSignature);
302  return(signature_info->blocksize);
303 }
304 
305 /*
306 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
307 % %
308 % %
309 % %
310 + G e t S i g n a t u r e D i g e s t %
311 % %
312 % %
313 % %
314 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
315 %
316 % GetSignatureDigest() returns the signature digest.
317 %
318 % The format of the GetSignatureDigest method is:
319 %
320 % const StringInfo *GetSignatureDigest(const SignatureInfo *signature_info)
321 %
322 % A description of each parameter follows:
323 %
324 % o signature_info: the signature info.
325 %
326 */
327 MagickPrivate const StringInfo *GetSignatureDigest(
328  const SignatureInfo *signature_info)
329 {
330  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
331  assert(signature_info != (SignatureInfo *) NULL);
332  assert(signature_info->signature == MagickCoreSignature);
333  return(signature_info->digest);
334 }
335 
336 /*
337 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
338 % %
339 % %
340 % %
341 + G e t S i g n a t u r e D i g e s t s i z e %
342 % %
343 % %
344 % %
345 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
346 %
347 % GetSignatureDigestsize() returns the Signature digest size.
348 %
349 % The format of the GetSignatureDigestsize method is:
350 %
351 % unsigned int *GetSignatureDigestsize(const SignatureInfo *signature_info)
352 %
353 % A description of each parameter follows:
354 %
355 % o signature_info: the signature info.
356 %
357 */
358 MagickPrivate unsigned int GetSignatureDigestsize(
359  const SignatureInfo *signature_info)
360 {
361  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
362  assert(signature_info != (SignatureInfo *) NULL);
363  assert(signature_info->signature == MagickCoreSignature);
364  return(signature_info->digestsize);
365 }
366 
367 /*
368 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
369 % %
370 % %
371 % %
372 + I n i t i a l i z e S i g n a t u r e %
373 % %
374 % %
375 % %
376 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
377 %
378 % InitializeSignature() initializes the Signature accumulator.
379 %
380 % The format of the DestroySignatureInfo method is:
381 %
382 % void InitializeSignatureInfo(SignatureInfo *signature_info)
383 %
384 % A description of each parameter follows:
385 %
386 % o signature_info: the cipher signature_info.
387 %
388 */
389 MagickPrivate void InitializeSignature(SignatureInfo *signature_info)
390 {
391  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
392  assert(signature_info != (SignatureInfo *) NULL);
393  assert(signature_info->signature == MagickCoreSignature);
394  signature_info->accumulator[0]=0x6a09e667U;
395  signature_info->accumulator[1]=0xbb67ae85U;
396  signature_info->accumulator[2]=0x3c6ef372U;
397  signature_info->accumulator[3]=0xa54ff53aU;
398  signature_info->accumulator[4]=0x510e527fU;
399  signature_info->accumulator[5]=0x9b05688cU;
400  signature_info->accumulator[6]=0x1f83d9abU;
401  signature_info->accumulator[7]=0x5be0cd19U;
402  signature_info->low_order=0;
403  signature_info->high_order=0;
404  signature_info->extent=0;
405 }
406 
407 /*
408 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
409 % %
410 % %
411 % %
412 + S e t S i g n a t u r e D i g e s t %
413 % %
414 % %
415 % %
416 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
417 %
418 % SetSignatureDigest() set the signature digest.
419 %
420 % The format of the SetSignatureDigest method is:
421 %
422 % SetSignatureDigest(SignatureInfo *signature_info,
423 % const StringInfo *digest)
424 %
425 % A description of each parameter follows:
426 %
427 % o signature_info: the signature info.
428 %
429 % o digest: the digest.
430 %
431 */
432 MagickPrivate void SetSignatureDigest(SignatureInfo *signature_info,
433  const StringInfo *digest)
434 {
435  /*
436  Set the signature accumulator.
437  */
438  assert(signature_info != (SignatureInfo *) NULL);
439  assert(signature_info->signature == MagickCoreSignature);
440  SetStringInfo(signature_info->digest,digest);
441 }
442 
443 /*
444 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
445 % %
446 % %
447 % %
448 % S i g n a t u r e I m a g e %
449 % %
450 % %
451 % %
452 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
453 %
454 % SignatureImage() computes a message digest from an image pixel stream with
455 % an implementation of the NIST SHA-256 Message Digest algorithm. This
456 % signature uniquely identifies the image and is convenient for determining
457 % if an image has been modified or whether two images are identical.
458 %
459 % The format of the SignatureImage method is:
460 %
461 % MagickBooleanType SignatureImage(Image *image,ExceptionInfo *exception)
462 %
463 % A description of each parameter follows:
464 %
465 % o image: the image.
466 %
467 % o exception: return any errors or warnings in this structure.
468 %
469 */
470 MagickExport MagickBooleanType SignatureImage(Image *image,
471  ExceptionInfo *exception)
472 {
473  CacheView
474  *image_view;
475 
476  char
477  *hex_signature;
478 
479  float
480  pixel;
481 
482  register const Quantum
483  *p;
484 
485  SignatureInfo
486  *signature_info;
487 
488  ssize_t
489  y;
490 
491  StringInfo
492  *signature;
493 
494  unsigned char
495  *pixels;
496 
497  /*
498  Compute image digital signature.
499  */
500  assert(image != (Image *) NULL);
501  assert(image->signature == MagickCoreSignature);
502  if (image->debug != MagickFalse)
503  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",image->filename);
504  signature_info=AcquireSignatureInfo();
505  signature=AcquireStringInfo(GetPixelChannels(image)*image->columns*
506  sizeof(pixel));
507  image_view=AcquireVirtualCacheView(image,exception);
508  for (y=0; y < (ssize_t) image->rows; y++)
509  {
510  register ssize_t
511  x;
512 
513  register unsigned char
514  *q;
515 
516  p=GetCacheViewVirtualPixels(image_view,0,y,image->columns,1,exception);
517  if (p == (const Quantum *) NULL)
518  break;
519  SetStringInfoLength(signature,GetPixelChannels(image)*image->columns*
520  sizeof(pixel));
521  pixels=GetStringInfoDatum(signature);
522  q=pixels;
523  for (x=0; x < (ssize_t) image->columns; x++)
524  {
525  register ssize_t
526  i;
527 
528  if (GetPixelReadMask(image,p) <= (QuantumRange/2))
529  {
530  p+=GetPixelChannels(image);
531  continue;
532  }
533  for (i=0; i < (ssize_t) GetPixelChannels(image); i++)
534  {
535  register ssize_t
536  j;
537 
538  PixelChannel channel = GetPixelChannelChannel(image,i);
539  PixelTrait traits = GetPixelChannelTraits(image,channel);
540  if ((traits & UpdatePixelTrait) == 0)
541  continue;
542  pixel=(float) (QuantumScale*p[i]);
543  if (signature_info->lsb_first == MagickFalse)
544  for (j=(ssize_t) sizeof(pixel)-1; j >= 0; j--)
545  *q++=(unsigned char) ((unsigned char *) &pixel)[j];
546  else
547  for (j=0; j < (ssize_t) sizeof(pixel); j++)
548  *q++=(unsigned char) ((unsigned char *) &pixel)[j];
549  }
550  p+=GetPixelChannels(image);
551  }
552  SetStringInfoLength(signature,(size_t) (q-pixels));
553  UpdateSignature(signature_info,signature);
554  }
555  image_view=DestroyCacheView(image_view);
556  FinalizeSignature(signature_info);
557  hex_signature=StringInfoToHexString(GetSignatureDigest(signature_info));
558  (void) DeleteImageProperty(image,"signature");
559  (void) SetImageProperty(image,"signature",hex_signature,exception);
560  /*
561  Free resources.
562  */
563  hex_signature=DestroyString(hex_signature);
564  signature=DestroyStringInfo(signature);
565  signature_info=DestroySignatureInfo(signature_info);
566  return(MagickTrue);
567 }
568 
569 /*
570 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
571 % %
572 % %
573 % %
574 + T r a n s f o r m S i g n a t u r e %
575 % %
576 % %
577 % %
578 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
579 %
580 % TransformSignature() transforms the Signature message accumulator.
581 %
582 % The format of the TransformSignature method is:
583 %
584 % TransformSignature(SignatureInfo *signature_info)
585 %
586 % A description of each parameter follows:
587 %
588 % o signature_info: the address of a structure of type SignatureInfo.
589 %
590 */
591 static void TransformSignature(SignatureInfo *signature_info)
592 {
593 #define Ch(x,y,z) (((x) & (y)) ^ (~(x) & (z)))
594 #define Maj(x,y,z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
595 #define RotateRight(x,n) (Trunc32(((x) >> n) | ((x) << (32-n))))
596 #define Sigma0(x) (RotateRight(x,7) ^ RotateRight(x,18) ^ Trunc32((x) >> 3))
597 #define Sigma1(x) (RotateRight(x,17) ^ RotateRight(x,19) ^ Trunc32((x) >> 10))
598 #define Suma0(x) (RotateRight(x,2) ^ RotateRight(x,13) ^ RotateRight(x,22))
599 #define Suma1(x) (RotateRight(x,6) ^ RotateRight(x,11) ^ RotateRight(x,25))
600 #define Trunc32(x) ((unsigned int) ((x) & 0xffffffffU))
601 
602  register ssize_t
603  i;
604 
605  register unsigned char
606  *p;
607 
608  ssize_t
609  j;
610 
611  static const unsigned int
612  K[64] =
613  {
614  0x428a2f98U, 0x71374491U, 0xb5c0fbcfU, 0xe9b5dba5U, 0x3956c25bU,
615  0x59f111f1U, 0x923f82a4U, 0xab1c5ed5U, 0xd807aa98U, 0x12835b01U,
616  0x243185beU, 0x550c7dc3U, 0x72be5d74U, 0x80deb1feU, 0x9bdc06a7U,
617  0xc19bf174U, 0xe49b69c1U, 0xefbe4786U, 0x0fc19dc6U, 0x240ca1ccU,
618  0x2de92c6fU, 0x4a7484aaU, 0x5cb0a9dcU, 0x76f988daU, 0x983e5152U,
619  0xa831c66dU, 0xb00327c8U, 0xbf597fc7U, 0xc6e00bf3U, 0xd5a79147U,
620  0x06ca6351U, 0x14292967U, 0x27b70a85U, 0x2e1b2138U, 0x4d2c6dfcU,
621  0x53380d13U, 0x650a7354U, 0x766a0abbU, 0x81c2c92eU, 0x92722c85U,
622  0xa2bfe8a1U, 0xa81a664bU, 0xc24b8b70U, 0xc76c51a3U, 0xd192e819U,
623  0xd6990624U, 0xf40e3585U, 0x106aa070U, 0x19a4c116U, 0x1e376c08U,
624  0x2748774cU, 0x34b0bcb5U, 0x391c0cb3U, 0x4ed8aa4aU, 0x5b9cca4fU,
625  0x682e6ff3U, 0x748f82eeU, 0x78a5636fU, 0x84c87814U, 0x8cc70208U,
626  0x90befffaU, 0xa4506cebU, 0xbef9a3f7U, 0xc67178f2U
627  }; /* 32-bit fractional part of the cube root of the first 64 primes */
628 
629  unsigned int
630  A,
631  B,
632  C,
633  D,
634  E,
635  F,
636  G,
637  H,
638  shift,
639  T,
640  T1,
641  T2,
642  W[64];
643 
644  shift=32;
645  p=GetStringInfoDatum(signature_info->message);
646  if (signature_info->lsb_first == MagickFalse)
647  {
648 DisableMSCWarning(4127)
649  if (sizeof(unsigned int) <= 4)
650 RestoreMSCWarning
651  for (i=0; i < 16; i++)
652  {
653  T=(*((unsigned int *) p));
654  p+=4;
655  W[i]=Trunc32(T);
656  }
657  else
658  for (i=0; i < 16; i+=2)
659  {
660  T=(*((unsigned int *) p));
661  p+=8;
662  W[i]=Trunc32(T >> shift);
663  W[i+1]=Trunc32(T);
664  }
665  }
666  else
667 DisableMSCWarning(4127)
668  if (sizeof(unsigned int) <= 4)
669 RestoreMSCWarning
670  for (i=0; i < 16; i++)
671  {
672  T=(*((unsigned int *) p));
673  p+=4;
674  W[i]=((T << 24) & 0xff000000) | ((T << 8) & 0x00ff0000) |
675  ((T >> 8) & 0x0000ff00) | ((T >> 24) & 0x000000ff);
676  }
677  else
678  for (i=0; i < 16; i+=2)
679  {
680  T=(*((unsigned int *) p));
681  p+=8;
682  W[i]=((T << 24) & 0xff000000) | ((T << 8) & 0x00ff0000) |
683  ((T >> 8) & 0x0000ff00) | ((T >> 24) & 0x000000ff);
684  T>>=shift;
685  W[i+1]=((T << 24) & 0xff000000) | ((T << 8) & 0x00ff0000) |
686  ((T >> 8) & 0x0000ff00) | ((T >> 24) & 0x000000ff);
687  }
688  /*
689  Copy accumulator to registers.
690  */
691  A=signature_info->accumulator[0];
692  B=signature_info->accumulator[1];
693  C=signature_info->accumulator[2];
694  D=signature_info->accumulator[3];
695  E=signature_info->accumulator[4];
696  F=signature_info->accumulator[5];
697  G=signature_info->accumulator[6];
698  H=signature_info->accumulator[7];
699  for (i=16; i < 64; i++)
700  W[i]=Trunc32(Sigma1(W[i-2])+W[i-7]+Sigma0(W[i-15])+W[i-16]);
701  for (j=0; j < 64; j++)
702  {
703  T1=Trunc32(H+Suma1(E)+Ch(E,F,G)+K[j]+W[j]);
704  T2=Trunc32(Suma0(A)+Maj(A,B,C));
705  H=G;
706  G=F;
707  F=E;
708  E=Trunc32(D+T1);
709  D=C;
710  C=B;
711  B=A;
712  A=Trunc32(T1+T2);
713  }
714  /*
715  Add registers back to accumulator.
716  */
717  signature_info->accumulator[0]=Trunc32(signature_info->accumulator[0]+A);
718  signature_info->accumulator[1]=Trunc32(signature_info->accumulator[1]+B);
719  signature_info->accumulator[2]=Trunc32(signature_info->accumulator[2]+C);
720  signature_info->accumulator[3]=Trunc32(signature_info->accumulator[3]+D);
721  signature_info->accumulator[4]=Trunc32(signature_info->accumulator[4]+E);
722  signature_info->accumulator[5]=Trunc32(signature_info->accumulator[5]+F);
723  signature_info->accumulator[6]=Trunc32(signature_info->accumulator[6]+G);
724  signature_info->accumulator[7]=Trunc32(signature_info->accumulator[7]+H);
725  /*
726  Reset working registers.
727  */
728  A=0;
729  B=0;
730  C=0;
731  D=0;
732  E=0;
733  F=0;
734  G=0;
735  H=0;
736  T=0;
737  T1=0;
738  T2=0;
739  (void) memset(W,0,sizeof(W));
740 }
741 
742 /*
743 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
744 % %
745 % %
746 % %
747 + U p d a t e S i g n a t u r e %
748 % %
749 % %
750 % %
751 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
752 %
753 % UpdateSignature() updates the Signature message accumulator.
754 %
755 % The format of the UpdateSignature method is:
756 %
757 % UpdateSignature(SignatureInfo *signature_info,const StringInfo *message)
758 %
759 % A description of each parameter follows:
760 %
761 % o signature_info: the address of a structure of type SignatureInfo.
762 %
763 % o message: the message.
764 %
765 */
766 MagickPrivate void UpdateSignature(SignatureInfo *signature_info,
767  const StringInfo *message)
768 {
769  register size_t
770  i;
771 
772  register unsigned char
773  *p;
774 
775  size_t
776  n;
777 
778  unsigned int
779  length;
780 
781  /*
782  Update the Signature accumulator.
783  */
784  assert(signature_info != (SignatureInfo *) NULL);
785  assert(signature_info->signature == MagickCoreSignature);
786  n=GetStringInfoLength(message);
787  length=Trunc32((unsigned int) (signature_info->low_order+(n << 3)));
788  if (length < signature_info->low_order)
789  signature_info->high_order++;
790  signature_info->low_order=length;
791  signature_info->high_order+=(unsigned int) n >> 29;
792  p=GetStringInfoDatum(message);
793  if (signature_info->extent != 0)
794  {
795  i=GetStringInfoLength(signature_info->message)-signature_info->extent;
796  if (i > n)
797  i=n;
798  (void) memcpy(GetStringInfoDatum(signature_info->message)+
799  signature_info->extent,p,i);
800  n-=i;
801  p+=i;
802  signature_info->extent+=i;
803  if (signature_info->extent != GetStringInfoLength(signature_info->message))
804  return;
805  TransformSignature(signature_info);
806  }
807  while (n >= GetStringInfoLength(signature_info->message))
808  {
809  SetStringInfoDatum(signature_info->message,p);
810  p+=GetStringInfoLength(signature_info->message);
811  n-=GetStringInfoLength(signature_info->message);
812  TransformSignature(signature_info);
813  }
814  (void) memcpy(GetStringInfoDatum(signature_info->message),p,n);
815  signature_info->extent=n;
816 }
_Image::rows
size_t rows
Definition: image.h:172
DestroyCacheView
MagickExport CacheView * DestroyCacheView(CacheView *cache_view)
Definition: cache-view.c:252
Suma1
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Definition: signature.c:66
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#define DisableMSCWarning(nr)
Definition: studio.h:351
_SignatureInfo::high_order
unsigned int high_order
Definition: signature.c:77
_SignatureInfo::low_order
unsigned int low_order
Definition: signature.c:77
_SignatureInfo::extent
size_t extent
Definition: signature.c:82
TransformSignature
static void TransformSignature(SignatureInfo *)
Definition: signature.c:591
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#define ThrowFatalException(severity, tag)
Definition: exception-private.h:35
AcquireSignatureInfo
MagickPrivate SignatureInfo * AcquireSignatureInfo(void)
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Definition: exception.h:101
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#define Ch(x, y, z)
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MagickPrivate void InitializeSignature(SignatureInfo *)
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static PixelTrait GetPixelChannelTraits(const Image *magick_restrict image, const PixelChannel channel)
Definition: pixel-accessor.h:131
GetPixelReadMask
static Quantum GetPixelReadMask(const Image *magick_restrict image, const Quantum *magick_restrict pixel)
Definition: pixel-accessor.h:344
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MagickExport MagickBooleanType SignatureImage(Image *image, ExceptionInfo *exception)
Definition: signature.c:470
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Definition: cache-view.c:65
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Definition: cache-view.c:651
_SignatureInfo::signature
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Definition: signature.c:91
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Definition: signature.c:60
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Definition: signature.c:73
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#define MagickCoreSignature
Definition: method-attribute.h:86
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DestroySignatureInfo
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Definition: signature.c:171
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#define SignatureDigestsize
Definition: signature.c:61
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MagickExport unsigned char * GetStringInfoDatum(const StringInfo *string_info)
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Definition: magick-type.h:169
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Definition: studio.h:352
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MagickExport MagickBooleanType SetImageProperty(Image *image, const char *property, const char *value, ExceptionInfo *exception)
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MagickExport MagickBooleanType LogMagickEvent(const LogEventType type, const char *module, const char *function, const size_t line, const char *format,...)
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unsigned int blocksize
Definition: signature.c:69
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static size_t GetPixelChannels(const Image *magick_restrict image)
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Definition: property.c:279
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