NAME

       CMS_add1_recipient_cert, CMS_add0_recipient_key - add recipients to a CMS enveloped data
       structure

SYNOPSIS

        #include <openssl/cms.h>

        CMS_RecipientInfo *CMS_add1_recipient_cert(CMS_ContentInfo *cms,
                                                   X509 *recip, unsigned int flags);

        CMS_RecipientInfo *CMS_add0_recipient_key(CMS_ContentInfo *cms, int nid,
                                                  unsigned char *key, size_t keylen,
                                                  unsigned char *id, size_t idlen,
                                                  ASN1_GENERALIZEDTIME *date,
                                                  ASN1_OBJECT *otherTypeId,
                                                  ASN1_TYPE *otherType);

DESCRIPTION

       CMS_add1_recipient_cert() adds recipient recip to CMS_ContentInfo enveloped data structure
       cms as a KeyTransRecipientInfo structure.

       CMS_add0_recipient_key() adds symmetric key key of length keylen using wrapping algorithm
       nid, identifier id of length idlen and optional values date, otherTypeId and otherType to
       CMS_ContentInfo enveloped data structure cms as a KEKRecipientInfo structure.

       The CMS_ContentInfo structure should be obtained from an initial call to CMS_encrypt()
       with the flag CMS_PARTIAL set.

NOTES

       The main purpose of this function is to provide finer control over a CMS enveloped data
       structure where the simpler CMS_encrypt() function defaults are not appropriate. For
       example if one or more KEKRecipientInfo structures need to be added. New attributes can
       also be added using the returned CMS_RecipientInfo structure and the CMS attribute utility
       functions.

       OpenSSL will by default identify recipient certificates using issuer name and serial
       number. If CMS_USE_KEYID is set it will use the subject key identifier value instead. An
       error occurs if all recipient certificates do not have a subject key identifier extension.

       Currently only AES based key wrapping algorithms are supported for nid, specifically:
       NID_id_aes128_wrap, NID_id_aes192_wrap and NID_id_aes256_wrap.  If nid is set to NID_undef
       then an AES wrap algorithm will be used consistent with keylen.

RETURN VALUES

       CMS_add1_recipient_cert() and CMS_add0_recipient_key() return an internal pointer to the
       CMS_RecipientInfo structure just added or NULL if an error occurs.

SEE ALSO

       ERR_get_error(3), CMS_decrypt(3), CMS_final(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>.