.\"	$OpenBSD: d2i_X509_EXTENSION.3,v 1.4 2018/03/27 17:35:50 schwarze Exp $
.\"
.\" Copyright (c) 2016 Ingo Schwarze <schwarze@openbsd.org>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate: March 27 2018 $
.Dt D2I_X509_EXTENSION 3
.Os
.Sh NAME
.Nm d2i_X509_EXTENSION ,
.Nm i2d_X509_EXTENSION ,
.Nm d2i_X509_EXTENSIONS ,
.Nm i2d_X509_EXTENSIONS
.\" In the next line, the capital "E" is not a typo.
.\" The ASN.1 structure is called "Extensions", not "extensions".
.Nd decode and encode X.509 Extensions
.Sh SYNOPSIS
.In openssl/x509.h
.Ft X509_EXTENSION *
.Fo d2i_X509_EXTENSION
.Fa "X509_EXTENSION **val_out"
.Fa "const unsigned char **der_in"
.Fa "long length"
.Fc
.Ft int
.Fo i2d_X509_EXTENSION
.Fa "X509_EXTENSION *val_in"
.Fa "unsigned char **der_out"
.Fc
.Ft X509_EXTENSIONS *
.Fo d2i_X509_EXTENSIONS
.Fa "X509_EXTENSIONS **val_out"
.Fa "const unsigned char **der_in"
.Fa "long length"
.Fc
.Ft int
.Fo i2d_X509_EXTENSIONS
.Fa "X509_EXTENSIONS *val_in"
.Fa "unsigned char **der_out"
.Fc
.Sh DESCRIPTION
.Fn d2i_X509_EXTENSION
and
.Fn i2d_X509_EXTENSION
decode and encode an ASN.1
.Vt Extension
structure defined in RFC 5280 section 4.1.
.Pp
.Fn d2i_X509_EXTENSIONS
and
.Fn i2d_X509_EXTENSIONS
decode and encode an ASN.1
.Vt Extensions
structure defined in RFC 5280 section 4.1,
which is a SEQUENCE OF
.Vt Extension .
.Sh RETURN VALUES
.Fn d2i_X509_EXTENSION
and
.Fn d2i_X509_EXTENSIONS
return an
.Vt X509_EXTENSION
or
.Vt X509_EXTENSIONS
object, respectively, or
.Dv NULL
if an error occurs.
.Pp
.Fn i2d_X509_EXTENSION
and
.Fn i2d_X509_EXTENSIONS
return the number of bytes successfully encoded or a negative value
if an error occurs.
.Sh SEE ALSO
.Xr ASN1_item_d2i 3 ,
.Xr X509_EXTENSION_new 3 ,
.Xr X509V3_get_d2i 3 ,
.Xr X509v3_get_ext_by_NID 3
.Sh STANDARDS
RFC 5280: Internet X.509 Public Key Infrastructure Certificate and
Certificate Revocation List (CRL) Profile
.Sh HISTORY
.Fn d2i_X509_EXTENSION
and
.Fn i2d_X509_EXTENSION
first appeared in SSLeay 0.6.2 and have been available since
.Ox 2.4 .
.Pp
.Fn d2i_X509_EXTENSIONS
and
.Fn i2d_X509_EXTENSIONS
first appeared in OpenSSL 0.9.8h and have been available since
.Ox 4.5 .