generate RSA key pair
int bits, BIGNUM *e,
unsigned long e, void (*callback)(int,
int, void *), void *cb_arg);
generates a key pair and stores it in rsa.
The modulus size will be of length bits, and the public exponent will be e. Key sizes with num < 1024 should be considered insecure. The exponent is an odd number, typically 3, 17 or 65537.
A callback function may be used to provide feedback about the
progress of the key generation. If cb is not
NULL, it will be called as follows using the
- 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 to
e, it is called as
BN_GENCB_call(cb, 3, 0).
The process is then repeated for prime q with
is deprecated. New applications should use
RSA_generate_key() works in the same way as
RSA_generate_key_ex() except it uses "old
style" call backs. See
BN_generate_prime(3) for further details.
RSA_generate_key_ex() returns 1 on success
or 0 on error.
RSA_generate_key() returns the key on
NULL on error.
The error codes can be obtained by ERR_get_error(3).
BN_generate_prime(3), RSA_get0_key(3), RSA_meth_set_keygen(3), RSA_new(3)
RSA_generate_key() appeared in SSLeay 0.4
or earlier and had its cb_arg argument added in SSLeay
0.9.0. It has been available since OpenBSD 2.4.
RSA_generate_key_ex() first appeared in
OpenSSL 0.9.8 and has been available since OpenBSD
2, x) is used with two different
RSA_generate_key() goes into an infinite
loop for illegal input values.