CMS_get0_type.pod revision 280304 
1=pod
2
3=head1 NAME
4
5 CMS_get0_type, CMS_set1_eContentType, CMS_get0_eContentType, CMS_get0_content - get and set CMS content types and content
6
7=head1 SYNOPSIS
8
9 #include <openssl/cms.h>
10
11 const ASN1_OBJECT *CMS_get0_type(CMS_ContentInfo *cms);
12 int CMS_set1_eContentType(CMS_ContentInfo *cms, const ASN1_OBJECT *oid);
13 const ASN1_OBJECT *CMS_get0_eContentType(CMS_ContentInfo *cms);
14 ASN1_OCTET_STRING **CMS_get0_content(CMS_ContentInfo *cms);
15
16=head1 DESCRIPTION
17
18CMS_get0_type() returns the content type of a CMS_ContentInfo structure as
19and ASN1_OBJECT pointer. An application can then decide how to process the
20CMS_ContentInfo structure based on this value.
21
22CMS_set1_eContentType() sets the embedded content type of a CMS_ContentInfo
23structure. It should be called with CMS functions with the B<CMS_PARTIAL>
24flag and B<before> the structure is finalised, otherwise the results are
25undefined.
26
27ASN1_OBJECT *CMS_get0_eContentType() returns a pointer to the embedded
28content type.
29
30CMS_get0_content() returns a pointer to the B<ASN1_OCTET_STRING> pointer
31containing the embedded content.
32
33=head1 NOTES
34
35As the B<0> implies CMS_get0_type(), CMS_get0_eContentType() and
36CMS_get0_content() return internal pointers which should B<not> be freed up.
37CMS_set1_eContentType() copies the supplied OID and it B<should> be freed up
38after use.
39
40The B<ASN1_OBJECT> values returned can be converted to an integer B<NID> value
41using OBJ_obj2nid(). For the currently supported content types the following
42values are returned:
43
44 NID_pkcs7_data
45 NID_pkcs7_signed
46 NID_pkcs7_digest
47 NID_id_smime_ct_compressedData:
48 NID_pkcs7_encrypted
49 NID_pkcs7_enveloped
50
51The return value of CMS_get0_content() is a pointer to the B<ASN1_OCTET_STRING>
52content pointer. That means that for example:
53
54 ASN1_OCTET_STRING **pconf = CMS_get0_content(cms);
55
56B<*pconf> could be NULL if there is no embedded content. Applications can
57access, modify or create the embedded content in a B<CMS_ContentInfo> structure
58using this function. Applications usually will not need to modify the
59embedded content as it is normally set by higher level functions.
60
61=head1 RETURN VALUES
62
63CMS_get0_type() and CMS_get0_eContentType() return and ASN1_OBJECT structure.
64
65CMS_set1_eContentType() returns 1 for success or 0 if an error occurred.  The
66error can be obtained from ERR_get_error(3).
67
68=head1 SEE ALSO
69
70L<ERR_get_error(3)|ERR_get_error(3)>
71
72=head1 HISTORY
73
74CMS_get0_type(), CMS_set1_eContentType() and CMS_get0_eContentType() were all
75first added to OpenSSL 0.9.8
76
77=cut
78