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Alphabetical listing for B

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BN_rand(3)
NAME
  BN_rand, BN_pseudo_rand - Generate pseudo-random number

SYNOPSIS
  #include <openssl/bn.h>

  int BN_rand(
	  BIGNUM *rnd,
	  int bits,
	  int top,
	  int bottom );

  int BN_pseudo_rand(
	  BIGNUM *rnd,
	  int bits,
	  int top,
	  int bottom );

  int BN_rand_range(
	  BIGNUM *rnd,
	  BIGNUM *range );

  int BN_pseudo_rand_range(
	  BIGNUM *rnd,
	  BIGNUM *range );

DESCRIPTION
  The BN_rand() function generates a cryptographically strong pseudo-random
  number of bits in length and stores it in rnd. If top is -1, the most
  significant bit of the random number can be zero. If top is 0, it is set to
  1, and if top is 1, the two most significant bits of the number will be set
  to 1, so that the product of two such random numbers will always have
  2*bits length.  If bottom is true, the number will be odd.

  The BN_pseudo_rand() function does the same, but pseudo-random numbers
  generated by this function are not necessarily unpredictable.	 They can be
  used for non-cryptographic purposes and for certain purposes in
  cryptographic protocols, but usually not for key generation etc.

  The BN_rand_range() function generates a cryptographically strong pseudo-
  random number rnd in the range 0 <lt>= rnd < range.  BN_pseudo_rand_range()
  does the same, but is based on BN_pseudo_rand(), and hence numbers
  generated by it are not necessarily unpredictible.

  The PRNG must be seeded prior to calling the BN_rand() or BN_rand_range()
  functions.

RETURN VALUES
  The functions return 1 on success, 0 on error. The error codes can be
  obtained by using ERR_get_error().

HISTORY
  The BN_rand() function is available in all versions of SSLeay and OpenSSL.
  The BN_pseudo_rand() function was added in OpenSSL 0.9.5. The top == -1
  case and the BN_rand_range() function were added in OpenSSL 0.9.6a.
  BN_pseudo_rand_range() was added in OpenSSL 0.9.6c.

SEE ALSO
  Functions: bn(3), err(3), rand_ssl(3), RAND_add(3), RAND_bytes(3)

Index for Section 3

Alphabetical listing for B

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