BN_generate_prime(3) OpenSSL BN_generate_prime(3)[top]NAMEBN_generate_prime, BN_is_prime,BN_is_prime_fasttest- generate primes and test for primalitySYNOPSIS#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);DESCRIPTIONBN_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 poten‐ tial 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,, 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.-1RETURN VALUESBN_generate_prime() returns the prime number on success, NULL other‐ wise. 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, andon error. The error codes can be obtained by ERR_get_error(3).-1SEE ALSObn(3), ERR_get_error(3), rand(3)HISTORYThe 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 0.9.5.1.0.0h2003-01-13 BN_generate_prime(3)

More information is available in_ _ _ | | | | | | | | | | | | __ | | __ __ | | __ __ | | __ \ \| |/ / \ \| |/ / \ \| |/ / \ \ / / \ \ / / \ \ / / \ / \ / \ / \_/ \_/ \_/

List of man pages available for

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]

Polar

Member of Polar

Based on Fawad Halim's script.

....................................................................

Vote for polarhome |