I would appreciate any donations. Wishlist or send e-mail type donations to maekawa AT daemon-systems.org.

Thank you.

RSA_generate_key(3) OpenSSL RSA_generate_key(3)NAMERSA_generate_key_ex, RSA_generate_key, RSA_generate_multi_prime_key - generate RSA key pairLIBRARYlibcrypto, -lcryptoSYNOPSIS#include <openssl/rsa.h> int RSA_generate_key_ex(RSA *rsa, int bits, BIGNUM *e, BN_GENCB *cb); int RSA_generate_multi_prime_key(RSA *rsa, int bits, int primes, BIGNUM *e, BN_GENCB *cb); Deprecated: #if OPENSSL_API_COMPAT < 0x00908000L RSA *RSA_generate_key(int num, unsigned long e, void (*callback)(int, int, void *), void *cb_arg); #endifDESCRIPTIONRSA_generate_key_ex() generates a 2-prime RSA key pair and stores it in theRSAstructure provided inrsa. The pseudo-random number generator must be seeded prior to calling RSA_generate_key_ex(). RSA_generate_multi_prime_key() generates a multi-prime RSA key pair and stores it in theRSAstructure provided inrsa. The number of primes is given by theprimesparameter. The pseudo-random number generator must be seeded prior to calling RSA_generate_multi_prime_key(). The modulus size will be of lengthbits, the number of primes to form the modulus will beprimes, and the public exponent will bee. Key sizes withnum< 1024 should be considered insecure. The exponent is an odd number, typically 3, 17 or 65537. In order to maintain adequate security level, the maximum number of permittedprimesdepends on modulus bit length: <1024 | >=1024 | >=4096 | >=8192 ------+--------+--------+------- 2 | 3 | 4 | 5 A callback function may be used to provide feedback about the progress of the key generation. Ifcbis notNULL, it will be called as follows using the BN_GENCB_call() function described on the BN_generate_prime(3) page. RSA_generate_prime() is similar to RSA_generate_prime_ex() but expects an old-style callback function; see BN_generate_prime(3) for information on the old-style callback. ⊕ While a random prime number is generated, it is called as described in BN_generate_prime(3). ⊕ When the n-th randomly generated prime is rejected as not suitable for the key,BN_GENCB_call(cb,2,n)is called. ⊕ When a random p has been found with p-1 relatively prime toe, it is called asBN_GENCB_call(cb,3,0). The process is then repeated for prime q and other primes (if any) withBN_GENCB_call(cb,3,i)whereiindicates the i-th prime.RETURNVALUESRSA_generate_multi_prime_key() returns 1 on success or 0 on error. RSA_generate_key_ex() returns 1 on success or 0 on error. The error codes can be obtained by ERR_get_error(3). RSA_generate_key() returns a pointer to the RSA structure orNULLif the key generation fails.BUGSBN_GENCB_call(cb,2,x)is used with two different meanings.SEEALSOERR_get_error(3), RAND_bytes(3), BN_generate_prime(3)HISTORYRSA_generate_key() was deprecated in OpenSSL 0.9.8; use RSA_generate_key_ex() instead.COPYRIGHTCopyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved. Licensed under the OpenSSL license (the "License"). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at <https://www.openssl.org/source/license.html>. 1.1.1 2018-09-17 RSA_generate_key(3)