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CMS_final(3)                        OpenSSL                       CMS_final(3)


NAME
       CMS_final, CMS_final_digest - finalise a CMS_ContentInfo structure

SYNOPSIS
        #include <openssl/cms.h>

        int CMS_final(CMS_ContentInfo *cms, BIO *data, BIO *dcont, unsigned int flags);
        int CMS_final_digest(CMS_ContentInfo *cms, const unsigned char *md,
                             unsigned int mdlen, BIO *dcont, unsigned int flags);

DESCRIPTION
       CMS_final() finalises the structure cms. Its purpose is to perform any
       operations necessary on cms (digest computation for example) and set
       the appropriate fields. The parameter data contains the content to be
       processed. The dcont parameter contains a BIO to write content to after
       processing: this is only used with detached data and will usually be
       set to NULL.

       CMS_final_digest() finalises the structure cms using a pre-computed
       digest, rather than computing the digest from the original data.

NOTES
       These functions will normally be called when the CMS_PARTIAL flag is
       used. It should only be used when streaming is not performed because
       the streaming I/O functions perform finalisation operations internally.

       To sign a pre-computed digest, CMS_sign(3) or CMS_sign_ex() is called
       with the data parameter set to NULL before the CMS structure is
       finalised with the digest provided to CMS_final_digest() in binary
       form.  When signing a pre-computed digest, the security relies on the
       digest and its computation from the original message being trusted.

RETURN VALUES
       CMS_final() and CMS_final_digest() return 1 for success or 0 for
       failure.

SEE ALSO
       ERR_get_error(3), CMS_sign(3), CMS_encrypt(3)

HISTORY
       CMS_final_digest() was added in OpenSSL 3.2.

COPYRIGHT
       Copyright 2008-2022 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (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>.

3.5.1                             2025-07-01                      CMS_final(3)