MagickCore  7.0.7
Convert, Edit, Or Compose Bitmap Images
random.c
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1 /*
2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 % %
4 % %
5 % RRRR AAA N N DDDD OOO M M %
6 % R R A A NN N D D O O MM MM %
7 % RRRR AAAAA N N N D D O O M M M %
8 % R R A A N NN D D O O M M %
9 % R R A A N N DDDD OOO M M %
10 % %
11 % %
12 % MagickCore Methods to Generate Random Numbers %
13 % %
14 % Software Design %
15 % Cristy %
16 % December 2001 %
17 % %
18 % %
19 % Copyright 1999-2018 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://www.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 % The generation of random numbers is too important to be left to chance.
36 % -- Tom Christiansen <tchrist@mox.perl.com>
37 %
38 %
39 */
40 
41 /*
42  Include declarations.
43 */
44 #if defined(__VMS)
45 #include <time.h>
46 #endif
47 #if defined(__MINGW32__)
48 #include <sys/time.h>
49 #endif
50 #include "MagickCore/studio.h"
51 #include "MagickCore/exception.h"
54 #include "MagickCore/memory_.h"
56 #include "MagickCore/semaphore.h"
57 #include "MagickCore/random_.h"
59 #include "MagickCore/resource_.h"
61 #include "MagickCore/string_.h"
62 #include "MagickCore/thread_.h"
64 #include "MagickCore/utility.h"
66 /*
67  Define declarations.
68 */
69 #define PseudoRandomHash SHA256Hash
70 #define RandomEntropyLevel 9
71 #define RandomFilename "reservoir.xdm"
72 #define RandomFiletype "random"
73 #define RandomProtocolMajorVersion 1
74 #define RandomProtocolMinorVersion 0
75 
76 /*
77  Typedef declarations.
78 */
80 {
83 
86  *reservoir;
87 
88  size_t
89  i;
90 
91  unsigned long
92  seed[4];
93 
94  double
96 
97  unsigned long
99 
100  unsigned short
103 
106 
107  ssize_t
109 
110  size_t
112 };
113 
114 /*
115  External declarations.
116 */
117 #if defined(__APPLE__) && !defined(TARGET_OS_IPHONE)
118 #include <crt_externs.h>
119 #define environ (*_NSGetEnviron())
120 #endif
121 
122 #if !defined(MAGICKCORE_WINDOWS_SUPPORT)
123 extern char
124  **environ;
125 #endif
126 
127 /*
128  Global declarations.
129 */
130 static SemaphoreInfo
132 
133 static unsigned long
134  secret_key = ~0UL;
135 
136 static MagickBooleanType
138 
139 /*
140  Forward declarations.
141 */
142 static StringInfo
144 
145 /*
146 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
147 % %
148 % %
149 % %
150 % A c q u i r e R a n d o m I n f o %
151 % %
152 % %
153 % %
154 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
155 %
156 % AcquireRandomInfo() allocates the RandomInfo structure.
157 %
158 % The format of the AcquireRandomInfo method is:
159 %
160 % RandomInfo *AcquireRandomInfo(void)
161 %
162 */
163 
165 {
166  const StringInfo
167  *digest;
168 
169  RandomInfo
170  *random_info;
171 
172  StringInfo
173  *entropy,
174  *key,
175  *nonce;
176 
177  random_info=(RandomInfo *) AcquireCriticalMemory(sizeof(*random_info));
178  (void) ResetMagickMemory(random_info,0,sizeof(*random_info));
179  random_info->signature_info=AcquireSignatureInfo();
181  random_info->signature_info));
182  ResetStringInfo(random_info->nonce);
184  random_info->signature_info));
185  ResetStringInfo(random_info->reservoir);
186  random_info->normalize=1.0/(~0UL);
187  random_info->secret_key=secret_key;
190  random_info->semaphore=AcquireSemaphoreInfo();
191  random_info->timestamp=(ssize_t) time(0);
192  random_info->signature=MagickCoreSignature;
193  /*
194  Seed random nonce.
195  */
196  nonce=GenerateEntropicChaos(random_info);
197  if (nonce == (StringInfo *) NULL)
198  ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
199  InitializeSignature(random_info->signature_info);
200  UpdateSignature(random_info->signature_info,nonce);
201  FinalizeSignature(random_info->signature_info);
203  random_info->signature_info)+1)/2);
204  SetStringInfo(nonce,GetSignatureDigest(random_info->signature_info));
205  SetStringInfo(random_info->nonce,nonce);
206  nonce=DestroyStringInfo(nonce);
207  /*
208  Seed random reservoir with entropic data.
209  */
210  entropy=GenerateEntropicChaos(random_info);
211  if (entropy == (StringInfo *) NULL)
212  ThrowFatalException(ResourceLimitFatalError,"MemoryAllocationFailed");
213  UpdateSignature(random_info->signature_info,entropy);
214  FinalizeSignature(random_info->signature_info);
216  random_info->signature_info));
217  entropy=DestroyStringInfo(entropy);
218  /*
219  Seed pseudo random number generator.
220  */
221  if (random_info->secret_key == ~0UL)
222  {
223  key=GetRandomKey(random_info,sizeof(random_info->secret_key));
224  (void) CopyMagickMemory(random_info->seed,GetStringInfoDatum(key),
225  GetStringInfoLength(key));
226  key=DestroyStringInfo(key);
227  }
228  else
229  {
232 
233  signature_info=AcquireSignatureInfo();
234  key=AcquireStringInfo(sizeof(random_info->secret_key));
235  SetStringInfoDatum(key,(unsigned char *) &random_info->secret_key);
236  UpdateSignature(signature_info,key);
237  key=DestroyStringInfo(key);
238  FinalizeSignature(signature_info);
239  digest=GetSignatureDigest(signature_info);
240  (void) CopyMagickMemory(random_info->seed,GetStringInfoDatum(digest),
241  MagickMin(GetSignatureDigestsize(signature_info),
242  sizeof(*random_info->seed)));
243  signature_info=DestroySignatureInfo(signature_info);
244  }
245  random_info->seed[1]=0x50a7f451UL;
246  random_info->seed[2]=0x5365417eUL;
247  random_info->seed[3]=0xc3a4171aUL;
248  return(random_info);
249 }
250 
251 /*
252 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
253 % %
254 % %
255 % %
256 + D e s t r o y R a n d o m I n f o %
257 % %
258 % %
259 % %
260 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
261 %
262 % DestroyRandomInfo() deallocates memory associated with the random
263 % reservoir.
264 %
265 % The format of the DestroyRandomInfo method is:
266 %
267 % RandomInfo *DestroyRandomInfo(RandomInfo *random_info)
268 %
269 % A description of each parameter follows:
270 %
271 % o random_info: the random info.
272 %
273 */
275 {
276  (void) LogMagickEvent(TraceEvent,GetMagickModule(),"...");
277  assert(random_info != (RandomInfo *) NULL);
278  assert(random_info->signature == MagickCoreSignature);
279  LockSemaphoreInfo(random_info->semaphore);
280  if (random_info->reservoir != (StringInfo *) NULL)
281  random_info->reservoir=DestroyStringInfo(random_info->reservoir);
282  if (random_info->nonce != (StringInfo *) NULL)
283  random_info->nonce=DestroyStringInfo(random_info->nonce);
284  if (random_info->signature_info != (SignatureInfo *) NULL)
286  random_info->signature_info);
287  (void) ResetMagickMemory(random_info->seed,0,sizeof(*random_info->seed));
288  random_info->signature=(~MagickCoreSignature);
289  UnlockSemaphoreInfo(random_info->semaphore);
290  RelinquishSemaphoreInfo(&random_info->semaphore);
291  random_info=(RandomInfo *) RelinquishMagickMemory(random_info);
292  return(random_info);
293 }
294 
295 /*
296 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
297 % %
298 % %
299 % %
300 + G e n e r a t e E n t r o p i c C h a o s %
301 % %
302 % %
303 % %
304 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
305 %
306 % GenerateEntropicChaos() generate entropic chaos used to initialize the
307 % random reservoir.
308 %
309 % The format of the GenerateEntropicChaos method is:
310 %
311 % StringInfo *GenerateEntropicChaos(RandomInfo *random_info)
312 %
313 % A description of each parameter follows:
314 %
315 % o random_info: the random info.
316 %
317 */
318 
319 #if !defined(MAGICKCORE_WINDOWS_SUPPORT)
320 static ssize_t ReadRandom(int file,unsigned char *source,size_t length)
321 {
322  register unsigned char
323  *q;
324 
325  ssize_t
326  offset,
327  count;
328 
329  offset=0;
330  for (q=source; length != 0; length-=count)
331  {
332  count=(ssize_t) read(file,q,length);
333  if (count <= 0)
334  {
335  count=0;
336  if (errno == EINTR)
337  continue;
338  return(-1);
339  }
340  q+=count;
341  offset+=count;
342  }
343  return(offset);
344 }
345 #endif
346 
348 {
349 #define MaxEntropyExtent 64
350 
352  tid;
353 
354  StringInfo
355  *chaos,
356  *entropy;
357 
358  size_t
359  nanoseconds,
360  seconds;
361 
362  ssize_t
363  pid;
364 
365  /*
366  Initialize random reservoir.
367  */
368  entropy=AcquireStringInfo(0);
369  LockSemaphoreInfo(random_info->semaphore);
370  chaos=AcquireStringInfo(sizeof(unsigned char *));
371  SetStringInfoDatum(chaos,(unsigned char *) &entropy);
372  ConcatenateStringInfo(entropy,chaos);
373  SetStringInfoDatum(chaos,(unsigned char *) entropy);
374  ConcatenateStringInfo(entropy,chaos);
375  pid=(ssize_t) getpid();
376  SetStringInfoLength(chaos,sizeof(pid));
377  SetStringInfoDatum(chaos,(unsigned char *) &pid);
378  ConcatenateStringInfo(entropy,chaos);
379  tid=GetMagickThreadId();
380  SetStringInfoLength(chaos,sizeof(tid));
381  SetStringInfoDatum(chaos,(unsigned char *) &tid);
382  ConcatenateStringInfo(entropy,chaos);
383 #if defined(MAGICKCORE_HAVE_SYSCONF) && defined(_SC_PHYS_PAGES)
384  {
385  ssize_t
386  pages;
387 
388  pages=(ssize_t) sysconf(_SC_PHYS_PAGES);
389  SetStringInfoLength(chaos,sizeof(pages));
390  SetStringInfoDatum(chaos,(unsigned char *) &pages);
391  ConcatenateStringInfo(entropy,chaos);
392  }
393 #endif
394 #if defined(MAGICKCORE_HAVE_GETRUSAGE) && defined(RUSAGE_SELF)
395  {
396  struct rusage
397  usage;
398 
399  if (getrusage(RUSAGE_SELF,&usage) == 0)
400  {
401  SetStringInfoLength(chaos,sizeof(usage));
402  SetStringInfoDatum(chaos,(unsigned char *) &usage);
403  }
404  }
405 #endif
406  seconds=time((time_t *) 0);
407  nanoseconds=0;
408 #if defined(MAGICKCORE_HAVE_GETTIMEOFDAY)
409  {
410  struct timeval
411  timer;
412 
413  if (gettimeofday(&timer,(struct timezone *) NULL) == 0)
414  {
415  seconds=timer.tv_sec;
416  nanoseconds=1000UL*timer.tv_usec;
417  }
418  }
419 #endif
420 #if defined(MAGICKCORE_HAVE_CLOCK_GETTIME) && defined(CLOCK_REALTIME_HR)
421  {
422  struct timespec
423  timer;
424 
425  if (clock_gettime(CLOCK_REALTIME_HR,&timer) == 0)
426  {
427  seconds=timer.tv_sec;
428  nanoseconds=timer.tv_nsec;
429  }
430  }
431 #endif
432  SetStringInfoLength(chaos,sizeof(seconds));
433  SetStringInfoDatum(chaos,(unsigned char *) &seconds);
434  ConcatenateStringInfo(entropy,chaos);
435  SetStringInfoLength(chaos,sizeof(nanoseconds));
436  SetStringInfoDatum(chaos,(unsigned char *) &nanoseconds);
437  ConcatenateStringInfo(entropy,chaos);
438  nanoseconds=0;
439 #if defined(MAGICKCORE_HAVE_CLOCK)
440  nanoseconds=clock();
441 #endif
442 #if defined(MAGICKCORE_HAVE_TIMES)
443  {
444  struct tms
445  timer;
446 
447  (void) times(&timer);
448  nanoseconds=timer.tms_utime+timer.tms_stime;
449  }
450 #endif
451  SetStringInfoLength(chaos,sizeof(nanoseconds));
452  SetStringInfoDatum(chaos,(unsigned char *) &nanoseconds);
453  ConcatenateStringInfo(entropy,chaos);
454 #if defined(MAGICKCORE_HAVE_MKSTEMP)
455  {
456  char
457  path[MagickPathExtent];
458 
459  int
460  file;
461 
462  (void) strcpy(path,"XXXXXX");
463  file=mkstemp(path);
464  if (file != -1)
465  {
466 #if defined(MAGICKCORE_HAVE_FCHMOD)
467  (void) fchmod(file,0600);
468 #endif
469 #if defined(__OS2__)
470  setmode(file,O_BINARY);
471 #endif
472  (void) close(file);
473  }
474  (void) remove_utf8(path);
475  SetStringInfoLength(chaos,strlen(path));
476  SetStringInfoDatum(chaos,(unsigned char *) path);
477  ConcatenateStringInfo(entropy,chaos);
478  }
479 #endif
480 #if defined(MAGICKCORE_WINDOWS_SUPPORT)
481  {
482  double
483  datum;
484 
485  LARGE_INTEGER
486  datum1;
487 
488  /*
489  Not crytographically strong but better than nothing.
490  */
491  datum=NTElapsedTime()+NTUserTime();
492  SetStringInfoLength(chaos,sizeof(datum));
493  SetStringInfoDatum(chaos,(unsigned char *) &datum);
494  ConcatenateStringInfo(entropy,chaos);
495  if (QueryPerformanceCounter(&datum1) != 0)
496  {
497  SetStringInfoLength(chaos,sizeof(datum1));
498  SetStringInfoDatum(chaos,(unsigned char *) &datum1);
499  ConcatenateStringInfo(entropy,chaos);
500  }
501  /*
502  Our best hope for true entropy.
503  */
505  (void) NTGatherRandomData(MaxEntropyExtent,GetStringInfoDatum(chaos));
506  ConcatenateStringInfo(entropy,chaos);
507  }
508 #else
509  {
510  char
511  *filename;
512 
513  int
514  file;
515 
516  ssize_t
517  count;
518 
519  StringInfo
520  *device;
521 
522  /*
523  Not crytographically strong but better than nothing.
524  */
525  if (environ != (char **) NULL)
526  {
527  register ssize_t
528  i;
529 
530  /*
531  Squeeze some entropy from the sometimes unpredicatble environment.
532  */
533  for (i=0; environ[i] != (char *) NULL; i++)
534  {
535  SetStringInfoLength(chaos,strlen(environ[i]));
536  SetStringInfoDatum(chaos,(unsigned char *) environ[i]);
537  ConcatenateStringInfo(entropy,chaos);
538  }
539  }
540  filename=AcquireString("/dev/urandom");
541  device=StringToStringInfo(filename);
542  device=DestroyStringInfo(device);
543  file=open_utf8(filename,O_RDONLY | O_BINARY,0);
544  filename=DestroyString(filename);
545  if (file != -1)
546  {
549  (void) close(file);
550  SetStringInfoLength(chaos,(size_t) count);
551  ConcatenateStringInfo(entropy,chaos);
552  }
554  {
555  /*
556  Our best hope for true entropy.
557  */
558  filename=AcquireString("/dev/random");
559  device=StringToStringInfo(filename);
560  device=DestroyStringInfo(device);
561  file=open_utf8(filename,O_RDONLY | O_BINARY,0);
562  filename=DestroyString(filename);
563  if (file == -1)
564  {
565  filename=AcquireString("/dev/srandom");
566  device=StringToStringInfo(filename);
567  device=DestroyStringInfo(device);
568  file=open_utf8(filename,O_RDONLY | O_BINARY,0);
569  }
570  if (file != -1)
571  {
574  (void) close(file);
575  SetStringInfoLength(chaos,(size_t) count);
576  ConcatenateStringInfo(entropy,chaos);
577  }
578  }
579  }
580 #endif
581  chaos=DestroyStringInfo(chaos);
582  UnlockSemaphoreInfo(random_info->semaphore);
583  return(entropy);
584 }
585 
586 /*
587 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
588 % %
589 % %
590 % %
591 % G e t P s e u d o R a n d o m V a l u e %
592 % %
593 % %
594 % %
595 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
596 %
597 % GetPseudoRandomValue() return a non-negative double-precision floating-point
598 % value uniformly distributed over the interval [0.0, 1.0) with a 2 to the
599 % 128th-1 period.
600 %
601 % The format of the GetPseudoRandomValue method is:
602 %
603 % double GetPseudoRandomValue(RandomInfo *randon_info)
604 %
605 % A description of each parameter follows:
606 %
607 % o random_info: the random info.
608 %
609 */
611 {
612  register unsigned long
613  *seed;
614 
615  unsigned long
616  alpha;
617 
618  seed=random_info->seed;
619  do
620  {
621  alpha=(unsigned long) (seed[1] ^ (seed[1] << 11));
622  seed[1]=seed[2];
623  seed[2]=seed[3];
624  seed[3]=seed[0];
625  seed[0]=(seed[0] ^ (seed[0] >> 19)) ^ (alpha ^ (alpha >> 8));
626  } while (seed[0] == ~0UL);
627  return(random_info->normalize*seed[0]);
628 }
629 
630 /*
631 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
632 % %
633 % %
634 % %
635 + G e t R a n d o m I n f o N o r m a l i z e %
636 % %
637 % %
638 % %
639 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
640 %
641 % GetRandomInfoNormalize() returns the random normalize value.
642 %
643 % The format of the GetRandomInfoNormalize method is:
644 %
645 % double GetRandomInfoNormalize(const RandomInfo *random_info)
646 %
647 % A description of each parameter follows:
648 %
649 % o random_info: the random info.
650 %
651 */
653 {
654  assert(random_info != (const RandomInfo *) NULL);
655  return(random_info->normalize);
656 }
657 
658 /*
659 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
660 % %
661 % %
662 % %
663 + G e t R a n d o m I n f o S e e d %
664 % %
665 % %
666 % %
667 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
668 %
669 % GetRandomInfoSeed() returns the random seed.
670 %
671 % The format of the GetRandomInfoSeed method is:
672 %
673 % unsigned long *GetRandomInfoSeed(RandomInfo *random_info)
674 %
675 % A description of each parameter follows:
676 %
677 % o random_info: the random info.
678 %
679 */
681 {
682  assert(random_info != (RandomInfo *) NULL);
683  return(random_info->seed);
684 }
685 
686 /*
687 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
688 % %
689 % %
690 % %
691 % G e t R a n d o m K e y %
692 % %
693 % %
694 % %
695 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
696 %
697 % GetRandomKey() gets a random key from the reservoir.
698 %
699 % The format of the GetRandomKey method is:
700 %
701 % StringInfo *GetRandomKey(RandomInfo *random_info,const size_t length)
702 %
703 % A description of each parameter follows:
704 %
705 % o random_info: the random info.
706 %
707 % o length: the key length.
708 %
709 */
711  const size_t length)
712 {
713  StringInfo
714  *key;
715 
716  assert(random_info != (RandomInfo *) NULL);
717  key=AcquireStringInfo(length);
718  SetRandomKey(random_info,length,GetStringInfoDatum(key));
719  return(key);
720 }
721 
722 /*
723 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
724 % %
725 % %
726 % %
727 % G e t R a n d o m S e c r e t K e y %
728 % %
729 % %
730 % %
731 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
732 %
733 % GetRandomSecretKey() returns the random secet key.
734 %
735 % The format of the GetRandomSecretKey method is:
736 %
737 % unsigned long GetRandomSecretKey(const RandomInfo *random_info)
738 %
739 % A description of each parameter follows:
740 %
741 % o random_info: the random info.
742 */
744 {
745  return(random_info->secret_key);
746 }
747 
748 /*
749 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
750 % %
751 % %
752 % %
753 % G e t R a n d o m V a l u e %
754 % %
755 % %
756 % %
757 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
758 %
759 % GetRandomValue() return a non-negative double-precision floating-point
760 % value uniformly distributed over the interval [0.0, 1.0) with a 2 to the
761 % 128th-1 period (not cryptographically strong).
762 %
763 % The format of the GetRandomValue method is:
764 %
765 % double GetRandomValue(void)
766 %
767 */
769 {
770  unsigned long
771  key,
772  range;
773 
774  range=(~0UL);
775  do
776  {
777  SetRandomKey(random_info,sizeof(key),(unsigned char *) &key);
778  } while (key == range);
779  return((double) key/range);
780 }
781 
782 /*
783 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
784 % %
785 % %
786 % %
787 + R a n d o m C o m p o n e n t G e n e s i s %
788 % %
789 % %
790 % %
791 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
792 %
793 % RandomComponentGenesis() instantiates the random component.
794 %
795 % The format of the RandomComponentGenesis method is:
796 %
797 % MagickBooleanType RandomComponentGenesis(void)
798 %
799 */
801 {
802  if (random_semaphore == (SemaphoreInfo *) NULL)
804  return(MagickTrue);
805 }
806 
807 /*
808 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
809 % %
810 % %
811 % %
812 + R a n d o m C o m p o n e n t T e r m i n u s %
813 % %
814 % %
815 % %
816 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
817 %
818 % RandomComponentTerminus() destroys the random component.
819 %
820 % The format of the RandomComponentTerminus method is:
821 %
822 % RandomComponentTerminus(void)
823 %
824 */
826 {
827  if (random_semaphore == (SemaphoreInfo *) NULL)
830 }
831 
832 /*
833 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
834 % %
835 % %
836 % %
837 % S e t R a n d o m K e y %
838 % %
839 % %
840 % %
841 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
842 %
843 % SetRandomKey() sets a random key from the reservoir.
844 %
845 % The format of the SetRandomKey method is:
846 %
847 % void SetRandomKey(RandomInfo *random_info,const size_t length,
848 % unsigned char *key)
849 %
850 % A description of each parameter follows:
851 %
852 % o random_info: the random info.
853 %
854 % o length: the key length.
855 %
856 % o key: the key.
857 %
858 */
859 
861 {
862  register ssize_t
863  i;
864 
865  unsigned char
866  *datum;
867 
868  datum=GetStringInfoDatum(nonce);
869  for (i=(ssize_t) (GetStringInfoLength(nonce)-1); i != 0; i--)
870  {
871  datum[i]++;
872  if (datum[i] != 0)
873  return;
874  }
875  ThrowFatalException(RandomFatalError,"SequenceWrapError");
876 }
877 
879  unsigned char *key)
880 {
881  register size_t
882  i;
883 
884  register unsigned char
885  *p;
886 
889 
890  unsigned char
891  *datum;
892 
893  assert(random_info != (RandomInfo *) NULL);
894  if (length == 0)
895  return;
896  LockSemaphoreInfo(random_info->semaphore);
897  signature_info=random_info->signature_info;
898  datum=GetStringInfoDatum(random_info->reservoir);
899  i=length;
900  for (p=key; (i != 0) && (random_info->i != 0); i--)
901  {
902  *p++=datum[random_info->i];
903  random_info->i++;
904  if (random_info->i == GetSignatureDigestsize(signature_info))
905  random_info->i=0;
906  }
907  while (i >= GetSignatureDigestsize(signature_info))
908  {
909  InitializeSignature(signature_info);
910  UpdateSignature(signature_info,random_info->nonce);
911  FinalizeSignature(signature_info);
912  IncrementRandomNonce(random_info->nonce);
914  signature_info)),GetSignatureDigestsize(signature_info));
915  p+=GetSignatureDigestsize(signature_info);
916  i-=GetSignatureDigestsize(signature_info);
917  }
918  if (i != 0)
919  {
920  InitializeSignature(signature_info);
921  UpdateSignature(signature_info,random_info->nonce);
922  FinalizeSignature(signature_info);
923  IncrementRandomNonce(random_info->nonce);
924  SetStringInfo(random_info->reservoir,GetSignatureDigest(signature_info));
925  random_info->i=i;
926  datum=GetStringInfoDatum(random_info->reservoir);
927  while (i-- != 0)
928  p[i]=datum[i];
929  }
930  UnlockSemaphoreInfo(random_info->semaphore);
931 }
932 
933 /*
934 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
935 % %
936 % %
937 % %
938 % S e t R a n d o m S e c r e t K e y %
939 % %
940 % %
941 % %
942 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
943 %
944 % SetRandomSecretKey() sets the pseudo-random number generator secret key.
945 %
946 % The format of the SetRandomSecretKey method is:
947 %
948 % void SetRandomSecretKey(const unsigned long key)
949 %
950 % A description of each parameter follows:
951 %
952 % o key: the secret seed.
953 %
954 */
955 MagickExport void SetRandomSecretKey(const unsigned long key)
956 {
957  secret_key=key;
958 }
959 
960 /*
961 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
962 % %
963 % %
964 % %
965 % S e t R a n d o m T r u e R a n d o m %
966 % %
967 % %
968 % %
969 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
970 %
971 % SetRandomTrueRandom() declares your intentions to use true random numbers.
972 % True random numbers are encouraged but may not always be practical because
973 % your application may block while entropy is gathered from your environment.
974 %
975 % The format of the SetRandomTrueRandom method is:
976 %
977 % void SetRandomTrueRandom(const MagickBooleanType true_random)
978 %
979 % A description of each parameter follows:
980 %
981 % o true_random: declare your intentions to use true-random number.
982 %
983 */
985 {
986  gather_true_random=true_random;
987 }
StringInfo * nonce
Definition: random.c:85
static MagickThreadType GetMagickThreadId(void)
#define RandomProtocolMajorVersion
Definition: random.c:73
static ssize_t ReadRandom(int file, unsigned char *source, size_t length)
Definition: random.c:320
MagickExport StringInfo * StringToStringInfo(const char *string)
Definition: string.c:2439
MagickExport void UnlockSemaphoreInfo(SemaphoreInfo *semaphore_info)
Definition: semaphore.c:450
MagickPrivate double GetRandomInfoNormalize(const RandomInfo *random_info)
Definition: random.c:652
#define ThrowFatalException(severity, tag)
MagickPrivate SignatureInfo * AcquireSignatureInfo(void)
#define MaxEntropyExtent
MagickExport SemaphoreInfo * AcquireSemaphoreInfo(void)
Definition: semaphore.c:192
MagickPrivate void InitializeSignature(SignatureInfo *)
MagickExport void ConcatenateStringInfo(StringInfo *string_info, const StringInfo *source)
Definition: string.c:536
unsigned short protocol_minor
Definition: random.c:101
MagickExport void SetRandomTrueRandom(const MagickBooleanType true_random)
Definition: random.c:984
unsigned short protocol_major
Definition: random.c:101
#define O_BINARY
Definition: studio.h:320
MagickPrivate MagickBooleanType RandomComponentGenesis(void)
Definition: random.c:800
Definition: log.h:52
MagickExport unsigned long GetRandomSecretKey(const RandomInfo *random_info)
Definition: random.c:743
MagickExport void SetRandomKey(RandomInfo *random_info, const size_t length, unsigned char *key)
Definition: random.c:878
MagickExport RandomInfo * DestroyRandomInfo(RandomInfo *random_info)
Definition: random.c:274
MagickPrivate void RandomComponentTerminus(void)
Definition: random.c:825
#define MagickCoreSignature
MagickPrivate void FinalizeSignature(SignatureInfo *)
MagickExport void LockSemaphoreInfo(SemaphoreInfo *semaphore_info)
Definition: semaphore.c:293
MagickPrivate SignatureInfo * DestroySignatureInfo(SignatureInfo *)
Definition: signature.c:167
MagickExport unsigned char * GetStringInfoDatum(const StringInfo *string_info)
Definition: string.c:1283
SemaphoreInfo * semaphore
Definition: random.c:105
SignatureInfo * signature_info
Definition: random.c:82
MagickBooleanType
Definition: magick-type.h:156
MagickExport char * AcquireString(const char *source)
Definition: string.c:124
MagickExport void * ResetMagickMemory(void *memory, int byte, const size_t size)
Definition: memory.c:1164
pid_t MagickThreadType
Definition: thread_.h:34
static int remove_utf8(const char *path)
MagickExport StringInfo * DestroyStringInfo(StringInfo *string_info)
Definition: string.c:837
MagickExport void ResetStringInfo(StringInfo *string_info)
Definition: string.c:1631
unsigned long seed[4]
Definition: random.c:92
size_t i
Definition: random.c:89
#define MagickPathExtent
MagickExport MagickBooleanType static void * AcquireCriticalMemory(const size_t size)
MagickExport MagickBooleanType LogMagickEvent(const LogEventType type, const char *module, const char *function, const size_t line, const char *format,...)
Definition: log.c:1397
static int open_utf8(const char *path, int flags, mode_t mode)
MagickExport RandomInfo * AcquireRandomInfo(void)
Definition: random.c:164
MagickExport double GetPseudoRandomValue(RandomInfo *random_info)
Definition: random.c:610
static SemaphoreInfo * random_semaphore
Definition: random.c:131
MagickExport StringInfo * AcquireStringInfo(const size_t length)
Definition: string.c:170
MagickPrivate void UpdateSignature(SignatureInfo *, const StringInfo *)
Definition: signature.c:779
ssize_t timestamp
Definition: random.c:108
#define GetMagickModule()
Definition: log.h:28
MagickExport double GetRandomValue(RandomInfo *random_info)
Definition: random.c:768
static void IncrementRandomNonce(StringInfo *nonce)
Definition: random.c:860
MagickExport void SetStringInfoLength(StringInfo *string_info, const size_t length)
Definition: string.c:1784
MagickExport char * DestroyString(char *string)
Definition: string.c:810
MagickExport void ActivateSemaphoreInfo(SemaphoreInfo **semaphore_info)
Definition: semaphore.c:97
StringInfo * reservoir
Definition: random.c:85
unsigned long secret_key
Definition: random.c:98
size_t signature
Definition: random.c:111
char ** environ
#define MagickMin(x, y)
Definition: image-private.h:27
static RandomInfo * random_info
Definition: resource.c:109
MagickExport void * RelinquishMagickMemory(void *memory)
Definition: memory.c:1038
double normalize
Definition: random.c:95
MagickPrivate const StringInfo * GetSignatureDigest(const SignatureInfo *)
Definition: signature.c:323
#define MagickPrivate
static StringInfo * GenerateEntropicChaos(RandomInfo *)
Definition: random.c:347
#define MagickExport
MagickExport StringInfo * GetRandomKey(RandomInfo *random_info, const size_t length)
Definition: random.c:710
static MagickBooleanType gather_true_random
Definition: random.c:137
MagickPrivate unsigned long * GetRandomInfoSeed(RandomInfo *random_info)
Definition: random.c:680
MagickPrivate unsigned int GetSignatureDigestsize(const SignatureInfo *)
Definition: signature.c:354
MagickExport void SetRandomSecretKey(const unsigned long key)
Definition: random.c:955
MagickExport size_t GetStringInfoLength(const StringInfo *string_info)
Definition: string.c:1312
MagickExport void RelinquishSemaphoreInfo(SemaphoreInfo **semaphore_info)
Definition: semaphore.c:351
MagickExport void * CopyMagickMemory(void *destination, const void *source, const size_t size)
Definition: memory.c:721
MagickExport void SetStringInfoDatum(StringInfo *string_info, const unsigned char *source)
Definition: string.c:1751
#define RandomProtocolMinorVersion
Definition: random.c:74
MagickExport void SetStringInfo(StringInfo *string_info, const StringInfo *source)
Definition: string.c:1711