BN_is_prime man page on MirBSD

Man page or keyword search:  
man Server   6113 pages
apropos Keyword Search (all sections)
Output format
MirBSD logo
[printable version]



BN_GENERATE_PRIME(3)	     OpenSSL	     BN_GENERATE_PRIME(3)

NAME
     BN_generate_prime, BN_is_prime, BN_is_prime_fasttest - gen-
     erate primes and test for primality

SYNOPSIS
      #include <openssl/bn.h>

      BIGNUM *BN_generate_prime(BIGNUM *ret, int num, int safe, BIGNUM *add,
	  BIGNUM *rem, void (*callback)(int, int, void *), void *cb_arg);

      int BN_is_prime(const BIGNUM *a, int checks, void (*callback)(int, int,
	  void *), BN_CTX *ctx, void *cb_arg);

      int BN_is_prime_fasttest(const BIGNUM *a, int checks,
	  void (*callback)(int, int, void *), BN_CTX *ctx, void *cb_arg,
	  int do_trial_division);

DESCRIPTION
     BN_generate_prime() generates a pseudo-random prime number
     of num bits. If ret is not NULL, it will be used to store
     the number.

     If callback is not NULL, it is called as follows:

     +	 callback(0, i, cb_arg) is called after generating the
	 i-th potential prime number.

     +	 While the number is being tested for primality, call-
	 back(1, j, cb_arg) is called as described below.

     +	 When a prime has been found, callback(2, i, cb_arg) is
	 called.

     The prime may have to fulfill additional requirements for
     use in Diffie-Hellman key exchange:

     If add is not NULL, the prime will fulfill the condition p %
     add == rem (p % add == 1 if rem == NULL) in order to suit a
     given generator.

     If safe is true, it will be a safe prime (i.e. a prime p so
     that (p-1)/2 is also prime).

     The PRNG must be seeded prior to calling
     BN_generate_prime(). The prime number generation has a
     negligible error probability.

     BN_is_prime() and BN_is_prime_fasttest() test if the number
     a is prime.  The following tests are performed until one of
     them shows that a is composite; if a passes all these tests,
     it is considered prime.

MirOS BSD #10-current	   2005-02-05				1

BN_GENERATE_PRIME(3)	     OpenSSL	     BN_GENERATE_PRIME(3)

     BN_is_prime_fasttest(), when called with do_trial_division
     == 1, first attempts trial division by a number of small
     primes; if no divisors are found by this test and callback
     is not NULL, callback(1, -1, cb_arg) is called. If
     do_trial_division == 0, this test is skipped.

     Both BN_is_prime() and BN_is_prime_fasttest() perform a
     Miller-Rabin probabilistic primality test with checks itera-
     tions. If checks == BN_prime_checks, a number of iterations
     is used that yields a false positive rate of at most 2^-80
     for random input.

     If callback is not NULL, callback(1, j, cb_arg) is called
     after the j-th iteration (j = 0, 1, ...). ctx is a pre-
     allocated BN_CTX (to save the overhead of allocating and
     freeing the structure in a loop), or NULL.

RETURN VALUES
     BN_generate_prime() returns the prime number on success,
     NULL otherwise.

     BN_is_prime() returns 0 if the number is composite, 1 if it
     is prime with an error probability of less than 0.25^checks,
     and -1 on error.

     The error codes can be obtained by ERR_get_error(3).

SEE ALSO
     bn(3), ERR_get_error(3), rand(3)

HISTORY
     The cb_arg arguments to BN_generate_prime() and to
     BN_is_prime() were added in SSLeay 0.9.0. The ret argument
     to BN_generate_prime() was added in SSLeay 0.9.1.
     BN_is_prime_fasttest() was added in OpenSSL 0.9.5.

MirOS BSD #10-current	   2005-02-05				2

[top]

List of man pages available for MirBSD

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net