=pod =head1 NAME DSA_generate_parameters_ex, DSA_generate_parameters - generate DSA parameters =head1 SYNOPSIS #include int DSA_generate_parameters_ex(DSA *dsa, int bits, const unsigned char *seed, int seed_len, int *counter_ret, unsigned long *h_ret, BN_GENCB *cb); Deprecated: #if OPENSSL_API_COMPAT < 0x00908000L DSA *DSA_generate_parameters(int bits, unsigned char *seed, int seed_len, int *counter_ret, unsigned long *h_ret, void (*callback)(int, int, void *), void *cb_arg); #endif =head1 DESCRIPTION DSA_generate_parameters_ex() generates primes p and q and a generator g for use in the DSA and stores the result in B. B is the length of the prime p to be generated. For lengths under 2048 bits, the length of q is 160 bits; for lengths greater than or equal to 2048 bits, the length of q is set to 256 bits. If B is NULL, the primes will be generated at random. If B is less than the length of q, an error is returned. DSA_generate_parameters_ex() places the iteration count in *B and a counter used for finding a generator in *B, unless these are B. A callback function may be used to provide feedback about the progress of the key generation. If B is not B, it will be called as shown below. For information on the BN_GENCB structure and the BN_GENCB_call function discussed below, refer to L. =over 2 =item * When a candidate for q is generated, B is called (m is 0 for the first candidate). =item * When a candidate for q has passed a test by trial division, B is called. While a candidate for q is tested by Miller-Rabin primality tests, B is called in the outer loop (once for each witness that confirms that the candidate may be prime); i is the loop counter (starting at 0). =item * When a prime q has been found, B and B are called. =item * Before a candidate for p (other than the first) is generated and tested, B is called. =item * When a candidate for p has passed the test by trial division, B is called. While it is tested by the Miller-Rabin primality test, B is called in the outer loop (once for each witness that confirms that the candidate may be prime). i is the loop counter (starting at 0). =item * When p has been found, B is called. =item * When the generator has been found, B is called. =back DSA_generate_parameters() (deprecated) works in much the same way as for DSA_generate_parameters_ex, except that no B parameter is passed and instead a newly allocated B structure is returned. Additionally "old style" callbacks are used instead of the newer BN_GENCB based approach. Refer to L for further information. =head1 RETURN VALUE DSA_generate_parameters_ex() returns a 1 on success, or 0 otherwise. DSA_generate_parameters() returns a pointer to the DSA structure, or B if the parameter generation fails. The error codes can be obtained by L. =head1 BUGS Seed lengths E 20 are not supported. =head1 SEE ALSO L, L, L, L, L =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. =cut