openssl/doc/crypto/RSA_generate_key.pod
Rich Salz 53934822ac Clean up "generic" intro pod files.
Files like dh.pod, etc., mostly duplicated the API-specific pod files.
Removed the duplicated content; that often mean the whole file could
be removed.  Some of the content about internals got moved into README
files in the source tree.  Some content (e.g., err.pod) got moved
into other pod pages.

Annotate generic pages, remove dup NAME

Reviewed-by: Richard Levitte <levitte@openssl.org>
2016-06-09 16:39:19 -04:00

87 lines
2.4 KiB
Text

=pod
=head1 NAME
RSA_generate_key_ex, RSA_generate_key - generate RSA key pair
=head1 SYNOPSIS
#include <openssl/rsa.h>
int RSA_generate_key_ex(RSA *rsa, int bits, 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);
#endif
=head1 DESCRIPTION
RSA_generate_key_ex() generates a key pair and stores it in the B<RSA>
structure provided in B<rsa>. The pseudo-random number generator must
be seeded prior to calling RSA_generate_key_ex().
The modulus size will be of length B<bits>, and the public exponent will be
B<e>. Key sizes with B<num> E<lt> 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 B<cb> is not B<NULL>, it
will be called as follows using the BN_GENCB_call() function
described on the L<BN_generate_prime(3)> page.
=over 4
=item *
While a random prime number is generated, it is called as
described in L<BN_generate_prime(3)>.
=item *
When the n-th randomly generated prime is rejected as not
suitable for the key, B<BN_GENCB_call(cb, 2, n)> is called.
=item *
When a random p has been found with p-1 relatively prime to B<e>,
it is called as B<BN_GENCB_call(cb, 3, 0)>.
=back
The process is then repeated for prime q with B<BN_GENCB_call(cb, 3, 1)>.
RSA_generate_key is deprecated (new applications should use
RSA_generate_key_ex instead). RSA_generate_key works in the same was as
RSA_generate_key_ex except it uses "old style" call backs. See
L<BN_generate_prime(3)> for further details.
=head1 RETURN VALUE
If key generation fails, RSA_generate_key() returns B<NULL>.
The error codes can be obtained by L<ERR_get_error(3)>.
=head1 BUGS
B<BN_GENCB_call(cb, 2, x)> is used with two different meanings.
RSA_generate_key() goes into an infinite loop for illegal input values.
=head1 SEE ALSO
L<ERR_get_error(3)>, L<rand(3)>,
L<RSA_generate_key(3)>, L<BN_generate_prime(3)>
=head1 COPYRIGHT
Copyright 2000-2016 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
L<https://www.openssl.org/source/license.html>.
=cut