xref: /freebsd/crypto/openssl/doc/man3/CMS_uncompress.pod (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
1=pod
2
3=head1 NAME
4
5CMS_uncompress - uncompress a CMS CompressedData structure
6
7=head1 SYNOPSIS
8
9 #include <openssl/cms.h>
10
11 int CMS_uncompress(CMS_ContentInfo *cms, BIO *dcont, BIO *out, unsigned int flags);
12
13=head1 DESCRIPTION
14
15CMS_uncompress() extracts and uncompresses the content from a CMS
16CompressedData structure B<cms>. B<data> is a BIO to write the content to and
17B<flags> is an optional set of flags.
18
19The B<dcont> parameter is used in the rare case where the compressed content
20is detached. It will normally be set to NULL.
21
22=head1 NOTES
23
24The only currently supported compression algorithm is zlib: if the structure
25indicates the use of any other algorithm an error is returned.
26
27If zlib support is not compiled into OpenSSL then CMS_uncompress() will always
28return an error.
29
30The following flags can be passed in the B<flags> parameter.
31
32If the B<CMS_TEXT> flag is set MIME headers for type B<text/plain> are deleted
33from the content. If the content is not of type B<text/plain> then an error is
34returned.
35
36=head1 RETURN VALUES
37
38CMS_uncompress() returns either 1 for success or 0 for failure. The error can
39be obtained from ERR_get_error(3)
40
41=head1 BUGS
42
43The lack of single pass processing and the need to hold all data in memory as
44mentioned in CMS_verify() also applies to CMS_decompress().
45
46=head1 SEE ALSO
47
48L<ERR_get_error(3)>, L<CMS_compress(3)>
49
50=head1 COPYRIGHT
51
52Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
53
54Licensed under the Apache License 2.0 (the "License").  You may not use
55this file except in compliance with the License.  You can obtain a copy
56in the file LICENSE in the source distribution or at
57L<https://www.openssl.org/source/license.html>.
58
59=cut
60