.\"	$OpenBSD: DSA_new.3,v 1.10 2018/04/18 01:11:45 schwarze Exp $
.\"	OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100
.\"
.\" This file was written by Ulf Moeller <ulf@openssl.org>.
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.Dd $Mdocdate: April 18 2018 $
.Dt DSA_NEW 3
.Os
.Sh NAME
.Nm DSA_new ,
.Nm DSA_up_ref ,
.Nm DSA_free
.Nd allocate and free DSA objects
.Sh SYNOPSIS
.In openssl/dsa.h
.Ft DSA*
.Fn DSA_new void
.Ft int
.Fo DSA_up_ref
.Fa "DSA *dsa"
.Fc
.Ft void
.Fo DSA_free
.Fa "DSA *dsa"
.Fc
.Sh DESCRIPTION
The DSA functions implement the Digital Signature Algorithm.
.Pp
.Fn DSA_new
allocates and initializes a
.Vt DSA
structure, setting the reference count to 1.
It is equivalent to calling
.Xr DSA_new_method 3
with a
.Dv NULL
argument.
.Pp
.Fn DSA_up_ref
increments the reference count by 1.
.Pp
.Fn DSA_free
decrements the reference count by 1.
If it reaches 0, it frees the
.Vt DSA
structure and its components.
The values are erased before the memory is returned to the system.
If
.Fa dsa
is a
.Dv NULL
pointer, no action occurs.
.Sh RETURN VALUES
If the allocation fails,
.Fn DSA_new
returns
.Dv NULL
and sets an error code that can be obtained by
.Xr ERR_get_error 3 .
Otherwise it returns a pointer to the newly allocated structure.
.Pp
.Fn DSA_up_ref
returns 1 for success or 0 for failure.
.Sh SEE ALSO
.Xr BN_new 3 ,
.Xr d2i_DSAPublicKey 3 ,
.Xr DH_new 3 ,
.Xr DSA_do_sign 3 ,
.Xr DSA_dup_DH 3 ,
.Xr DSA_generate_key 3 ,
.Xr DSA_generate_parameters 3 ,
.Xr DSA_get0_pqg 3 ,
.Xr DSA_get_ex_new_index 3 ,
.Xr DSA_meth_new 3 ,
.Xr DSA_print 3 ,
.Xr DSA_set_method 3 ,
.Xr DSA_SIG_new 3 ,
.Xr DSA_sign 3 ,
.Xr DSA_size 3 ,
.Xr ERR_get_error 3 ,
.Xr EVP_PKEY_set1_DSA 3 ,
.Xr RSA_new 3
.Sh STANDARDS
US Federal Information Processing Standard FIPS 186 (Digital Signature
Standard, DSS), ANSI X9.30
.Sh HISTORY
.Fn DSA_new
and
.Fn DSA_free
first appeared in SSLeay 0.6.0 and have been available since
.Ox 2.4 .
.Pp
.Fn DSA_up_ref
first appeared in OpenSSL 0.9.7 and has been available since
.Ox 3.2 .