1BIO_NEW_CMS(3) OpenSSL BIO_NEW_CMS(3)
2
3
4
6 BIO_new_CMS - CMS streaming filter BIO
7
9 #include <openssl/cms.h>
10
11 BIO *BIO_new_CMS(BIO *out, CMS_ContentInfo *cms);
12
14 BIO_new_CMS() returns a streaming filter BIO chain based on cms. The
15 output of the filter is written to out. Any data written to the chain
16 is automatically translated to a BER format CMS structure of the
17 appropriate type.
18
20 The chain returned by this function behaves like a standard filter BIO.
21 It supports non blocking I/O. Content is processed and streamed on the
22 fly and not all held in memory at once: so it is possible to encode
23 very large structures. After all content has been written through the
24 chain BIO_flush() must be called to finalise the structure.
25
26 The CMS_STREAM flag must be included in the corresponding flags
27 parameter of the cms creation function.
28
29 If an application wishes to write additional data to out BIOs should be
30 removed from the chain using BIO_pop() and freed with BIO_free() until
31 out is reached. If no additional data needs to be written
32 BIO_free_all() can be called to free up the whole chain.
33
34 Any content written through the filter is used verbatim: no canonical
35 translation is performed.
36
37 It is possible to chain multiple BIOs to, for example, create a triple
38 wrapped signed, enveloped, signed structure. In this case it is the
39 applications responsibility to set the inner content type of any outer
40 CMS_ContentInfo structures.
41
42 Large numbers of small writes through the chain should be avoided as
43 this will produce an output consisting of lots of OCTET STRING
44 structures. Prepending a BIO_f_buffer() buffering BIO will prevent
45 this.
46
48 There is currently no corresponding inverse BIO: i.e. one which can
49 decode a CMS structure on the fly.
50
52 BIO_new_CMS() returns a BIO chain when successful or NULL if an error
53 occurred. The error can be obtained from ERR_get_error(3).
54
56 ERR_get_error(3), CMS_sign(3), CMS_encrypt(3)
57
59 The BIO_new_CMS() function was added in OpenSSL 1.0.0.
60
62 Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
63
64 Licensed under the OpenSSL license (the "License"). You may not use
65 this file except in compliance with the License. You can obtain a copy
66 in the file LICENSE in the source distribution or at
67 <https://www.openssl.org/source/license.html>.
68
69
70
711.1.1l 2021-09-15 BIO_NEW_CMS(3)