Updated: 2021/Apr/14


CMS_get0_type(3)                    OpenSSL                   CMS_get0_type(3)



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

LIBRARY
       libcrypto, -lcrypto

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 an 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 (such
       as CMS_sign, CMS_encrypt) 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 an 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 2008-2019 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>.



1.1.1i                            2019-03-12                  CMS_get0_type(3)