[thirdparty/openssl.git] / doc / man3 / SMIME_read_CMS.pod

=pod

=head1 NAME

SMIME_read_CMS - parse S/MIME message

=head1 SYNOPSIS

 #include <openssl/cms.h>

 CMS_ContentInfo *SMIME_read_CMS(BIO *in, BIO **bcont);

=head1 DESCRIPTION

SMIME_read_CMS() parses a message in S/MIME format.

B<in> is a BIO to read the message from.

If cleartext signing is used then the content is saved in a memory bio which is
written to B<*bcont>, otherwise B<*bcont> is set to NULL.

The parsed CMS_ContentInfo structure is returned or NULL if an
error occurred.

=head1 NOTES

If B<*bcont> is not NULL then the message is clear text signed. B<*bcont> can
then be passed to CMS_verify() with the B<CMS_DETACHED> flag set.

Otherwise the type of the returned structure can be determined
using CMS_get0_type().

To support future functionality if B<bcont> is not NULL B<*bcont> should be
initialized to NULL. For example:

 BIO *cont = NULL;
 CMS_ContentInfo *cms;

 cms = SMIME_read_CMS(in, &cont);

=head1 BUGS

The MIME parser used by SMIME_read_CMS() is somewhat primitive.  While it will
handle most S/MIME messages more complex compound formats may not work.

The parser assumes that the CMS_ContentInfo structure is always base64 encoded
and will not handle the case where it is in binary format or uses quoted
printable format.

The use of a memory BIO to hold the signed content limits the size of message
which can be processed due to memory restraints: a streaming single pass option
should be available.

=head1 RETURN VALUES

SMIME_read_CMS() returns a valid B<CMS_ContentInfo> structure or B<NULL>
if an error occurred. The error can be obtained from ERR_get_error(3).

=head1 SEE ALSO

L<ERR_get_error(3)>, L<CMS_type(3)>,
L<SMIME_read_CMS(3)>, L<CMS_sign(3)>,
L<CMS_verify(3)>, L<CMS_encrypt(3)>,
L<CMS_decrypt(3)>

=head1 COPYRIGHT

Copyright 2008-2016 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
Commit	Line	Data
e33ffaca DSH	1	=pod
	2
	3	=head1 NAME
	4
bb9ad09e	5	SMIME_read_CMS - parse S/MIME message
e33ffaca DSH	6
	7	=head1 SYNOPSIS
	8
	9	#include <openssl/cms.h>
	10
	11	CMS_ContentInfo SMIME_read_CMS(BIO in, BIO **bcont);
	12
	13	=head1 DESCRIPTION
	14
	15	SMIME_read_CMS() parses a message in S/MIME format.
	16
	17	B<in> is a BIO to read the message from.
	18
38d3a738 DSH	19	If cleartext signing is used then the content is saved in a memory bio which is
38d3a738 DSH	20	written to B<bcont>, otherwise B<bcont> is set to NULL.
e33ffaca	21
38d3a738	22	The parsed CMS_ContentInfo structure is returned or NULL if an
e33ffaca DSH	23	error occurred.
	24
	25	=head1 NOTES
	26
38d3a738 DSH	27	If B<bcont> is not NULL then the message is clear text signed. B<bcont> can
38d3a738 DSH	28	then be passed to CMS_verify() with the B<CMS_DETACHED> flag set.
e33ffaca DSH	29
	30	Otherwise the type of the returned structure can be determined
	31	using CMS_get0_type().
	32
38d3a738 DSH	33	To support future functionality if B<bcont> is not NULL B<*bcont> should be
38d3a738 DSH	34	initialized to NULL. For example:
e33ffaca DSH	35
	36	BIO *cont = NULL;
	37	CMS_ContentInfo *cms;
	38
	39	cms = SMIME_read_CMS(in, &cont);
	40
	41	=head1 BUGS
	42
38d3a738 DSH	43	The MIME parser used by SMIME_read_CMS() is somewhat primitive. While it will
38d3a738 DSH	44	handle most S/MIME messages more complex compound formats may not work.
e33ffaca	45
38d3a738 DSH	46	The parser assumes that the CMS_ContentInfo structure is always base64 encoded
	47	and will not handle the case where it is in binary format or uses quoted
	48	printable format.
e33ffaca	49
38d3a738 DSH	50	The use of a memory BIO to hold the signed content limits the size of message
	51	which can be processed due to memory restraints: a streaming single pass option
	52	should be available.
e33ffaca DSH	53
	54	=head1 RETURN VALUES
	55
	56	SMIME_read_CMS() returns a valid B<CMS_ContentInfo> structure or B<NULL>
	57	if an error occurred. The error can be obtained from ERR_get_error(3).
	58
	59	=head1 SEE ALSO
	60
b97fdb57	61	L<ERR_get_error(3)>, L<CMS_type(3)>,
9b86974e	62	L<SMIME_read_CMS(3)>, L<CMS_sign(3)>,
b97fdb57	63	L<CMS_verify(3)>, L<CMS_encrypt(3)>,
9b86974e	64	L<CMS_decrypt(3)>
e33ffaca	65
e2f92610 RS	66	=head1 COPYRIGHT
	67
	68	Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
	69
	70	Licensed under the OpenSSL license (the "License"). You may not use
	71	this file except in compliance with the License. You can obtain a copy
	72	in the file LICENSE in the source distribution or at
	73	L<https://www.openssl.org/source/license.html>.
	74
	75	=cut