BN_is_prime man page on Syllable

Man page or keyword search:  
man Server   2339 pages
apropos Keyword Search (all sections)
Output format
Syllable logo
[printable version]

BN_generate_prime(3)		    OpenSSL		  BN_generate_prime(3)

NAME
       BN_generate_prime, BN_is_prime, BN_is_prime_fasttest - generate 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, callback(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.

       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 iterations. 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.

0.9.8k				  2003-01-13		  BN_generate_prime(3)
[top]
                             _         _         _ 
                            | |       | |       | |     
                            | |       | |       | |     
                         __ | | __ __ | | __ __ | | __  
                         \ \| |/ / \ \| |/ / \ \| |/ /  
                          \ \ / /   \ \ / /   \ \ / /   
                           \   /     \   /     \   /    
                            \_/       \_/       \_/ 
More information is available in HTML format for server Syllable

List of man pages available for Syllable

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