NAME

       CMS_get0_type, CMS_set1_eContentType, CMS_get0_eContentType, CMS_get0_content - get and set CMS content
       types and content

SYNOPSIS

        #include <openssl/cms.h>

        const ASN1_OBJECT *CMS_get0_type(const CMS_ContentInfo *cms);
        int CMS_set1_eContentType(CMS_ContentInfo *cms, const ASN1_OBJECT *oid);
        const ASN1_OBJECT *CMS_get0_eContentType(CMS_ContentInfo *cms);
        ASN1_OCTET_STRING **CMS_get0_content(CMS_ContentInfo *cms);

DESCRIPTION

       CMS_get0_type() returns the content type of a CMS_ContentInfo structure as and ASN1_OBJECT pointer. An
       application can then decide how to process the CMS_ContentInfo structure based on this value.

       CMS_set1_eContentType() sets the embedded content type of a CMS_ContentInfo structure. It should be
       called with CMS functions with the CMS_PARTIAL flag and before the structure is finalised, otherwise the
       results are undefined.

       ASN1_OBJECT *CMS_get0_eContentType() returns a pointer to the embedded content type.

       CMS_get0_content() returns a pointer to the ASN1_OCTET_STRING pointer containing the embedded content.

NOTES

       As the 0 implies CMS_get0_type(), CMS_get0_eContentType() and CMS_get0_content() return internal pointers
       which should not be freed up.  CMS_set1_eContentType() copies the supplied OID and it should be freed up
       after use.

       The ASN1_OBJECT values returned can be converted to an integer NID value using OBJ_obj2nid(). For the
       currently supported content types the following values are returned:

        NID_pkcs7_data
        NID_pkcs7_signed
        NID_pkcs7_digest
        NID_id_smime_ct_compressedData:
        NID_pkcs7_encrypted
        NID_pkcs7_enveloped

       The return value of CMS_get0_content() is a pointer to the ASN1_OCTET_STRING content pointer. That means
       that for example:

        ASN1_OCTET_STRING **pconf = CMS_get0_content(cms);

       *pconf could be NULL if there is no embedded content. Applications can access, modify or create the
       embedded content in a CMS_ContentInfo structure using this function. Applications usually will not need
       to modify the embedded content as it is normally set by higher level functions.

RETURN VALUES

       CMS_get0_type() and CMS_get0_eContentType() return and ASN1_OBJECT structure.

       CMS_set1_eContentType() returns 1 for success or 0 if an error occurred.  The error can be obtained from
       ERR_get_error(3).

SEE ALSO

       ERR_get_error(3)

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
       <https://www.openssl.org/source/license.html>.