.\"	$OpenBSD: EVP_PKEY_print_private.3,v 1.2 2016/11/06 15:52:50 jmc Exp $
.\"
.Dd $Mdocdate: November 6 2016 $
.Dt EVP_PKEY_PRINT_PRIVATE 3
.Os
.Sh NAME
.Nm EVP_PKEY_print_public ,
.Nm EVP_PKEY_print_private ,
.Nm EVP_PKEY_print_params
.Nd public key algorithm printing routines
.Sh SYNOPSIS
.In openssl/evp.h
.Ft int
.Fo EVP_PKEY_print_public
.Fa "BIO *out"
.Fa "const EVP_PKEY *pkey"
.Fa "int indent"
.Fa "ASN1_PCTX *pctx"
.Fc
.Ft int
.Fo EVP_PKEY_print_private
.Fa "BIO *out"
.Fa "const EVP_PKEY *pkey"
.Fa "int indent"
.Fa "ASN1_PCTX *pctx"
.Fc
.Ft int
.Fo EVP_PKEY_print_params
.Fa "BIO *out"
.Fa "const EVP_PKEY *pkey"
.Fa "int indent"
.Fa "ASN1_PCTX *pctx"
.Fc
.Sh DESCRIPTION
The functions
.Fn EVP_PKEY_print_public ,
.Fn EVP_PKEY_print_private ,
and
.Fn EVP_PKEY_print_params
print out the public, private or parameter components of key
.Fa pkey ,
respectively.
The key is sent to
.Vt BIO
.Fa out
in human readable form.
The parameter
.Fa indent
indicates how far the printout should be indented.
.Pp
The
.Fa pctx
parameter allows the print output to be finely tuned by using ASN1
printing options.
If
.Fa pctx
is set to
.Dv NULL ,
then default values will be used.
Currently, no public key algorithms include any options in the
.Fa pctx
parameter.
.Pp
If the key does not include all the components indicated by the function,
then only those contained in the key will be printed.
For example, passing a public key to
.Fn EVP_PKEY_print_private
will only print the public components.
.Sh RETURN VALUES
These functions all return 1 for success and 0 or a negative value for
failure.
In particular, a return value of -2 indicates the operation is not
supported by the public key algorithm.
.Sh SEE ALSO
.Xr EVP_PKEY_CTX_new 3 ,
.Xr EVP_PKEY_keygen 3
.Sh HISTORY
These functions were first added to OpenSSL 1.0.0.