security/nss/lib/freebl/secrng.h

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  36
  37 #ifndef _SECRNG_H_
  38 #define _SECRNG_H_
  39 /*
  40  * secrng.h - public data structures and prototypes for the secure random
  41  *            number generator
  42  *
  43  * $Id: secrng.h,v 1.6 2006/10/12 02:23:49 wtchang%redhat.com Exp $
  44  */
  45
  46 /******************************************/
  47 /*
  48 ** Random number generation. A cryptographically strong random number
  49 ** generator.
  50 */
  51
  52 #include "blapi.h"
  53
  54 /* the number of bytes to read from the system random number generator */
  55 #define SYSTEM_RNG_SEED_COUNT 1024
  56
  57 SEC_BEGIN_PROTOS
  58
  59 /*
  60 ** The following functions are provided by the security library
  61 ** but are differently implemented for the UNIX, Win, and OS/2
  62 ** versions
  63 */
  64
  65 /*
  66 ** Get the "noisiest" information available on the system.
  67 ** The amount of data returned depends on the system implementation.
  68 ** It will not exceed maxbytes, but may be (much) less.
  69 ** Returns number of noise bytes copied into buf, or zero if error.
  70 */
  71 extern size_t RNG_GetNoise(void *buf, size_t maxbytes);
  72
  73 /*
  74 ** RNG_SystemInfoForRNG should be called before any use of SSL. It
  75 ** gathers up the system specific information to help seed the
  76 ** state of the global random number generator.
  77 */
  78 extern void RNG_SystemInfoForRNG(void);
  79
  80 /*
  81 ** Use the contents (and stat) of a file to help seed the
  82 ** global random number generator.
  83 */
  84 extern void RNG_FileForRNG(const char *filename);
  85
  86 /*
  87 ** Get maxbytes bytes of random data from the system random number
  88 ** generator.
  89 ** Returns the number of bytes copied into buf -- maxbytes if success
  90 ** or zero if error.
  91 ** Errors:
  92 **   PR_NOT_IMPLEMENTED_ERROR   There is no system RNG on the platform.
  93 **   SEC_ERROR_NEED_RANDOM      The system RNG failed.
  94 */
  95 extern size_t RNG_SystemRNG(void *buf, size_t maxbytes);
  96
  97 SEC_END_PROTOS
  98
  99 #endif /* _SECRNG_H_ */