Synopsis #include <openssl/rsa.h> RSA
*RSA_generate_key(int num, unsigned long e, void (*callback)(int,int,void
*), void *cb_arg);
DESCRIPTIONRSA_generate_key() generates a key pair and returns it in
a newly allocated RSA structure. The pseudo-random
number generator must be seeded prior to calling RSA_generate_key().
The modulus size will be num 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 callback is not NULL,
it will be called as follows:
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, callback(2, n, cb_arg) is called.
When a random p has been found with p-1 relatively
prime to e, it is called as callback(3,
0, cb_arg).
The process is then repeated for prime q with callback(3,
1, cb_arg).
RETURN VALUEIf key generation fails, RSA_generate_key() returns NULL;
the error codes can be obtained by ERR_get_error(3) . Restrictionscallback(2, x, cb_arg) is used with two
different meanings.
RSA_generate_key() goes into an infinite loop for illegal
input values.
SEE ALSOERR_get_error(3) , rand(3) , rsa(3) , RSA_free(3) HISTORYThe cb_arg argument was added in SSLeay
0.9.0.
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