SMIME_write_CMS(3)

NAME

        SMIME_write_CMS - convert CMS structure to S/MIME format.

SYNOPSIS

        #include <openssl/cms.h>

        int SMIME_write_CMS(BIO *out, CMS_ContentInfo *cms, BIO *data, int flags);

DESCRIPTION

       SMIME_write_CMS() adds the appropriate MIME headers to a CMS structure
       to produce an S/MIME message.

       out is the BIO to write the data to. cms is the appropriate CMS_Con-
       tentInfo structure. If streaming is enabled then the content must be
       supplied in the data argument. flags is an optional set of flags.

NOTES

       The following flags can be passed in the flags parameter.

       If CMS_DETACHED is set then cleartext signing will be used, this option
       only makes sense for SignedData where CMS_DETACHED is also set when
       CMS_sign() is called.

       If the CMS_TEXT flag is set MIME headers for type text/plain are added
       to the content, this only makes sense if CMS_DETACHED is also set.

       If the CMS_STREAM flag is set streaming is performed. This flag should
       only be set if CMS_STREAM was also set in the previous call to a
       CMS_ContentInfo creation function.

       If cleartext signing is being used and CMS_STREAM not set then the data
       must be read twice: once to compute the signature in CMS_sign() and
       once to output the S/MIME message.

       If streaming is performed the content is output in BER format using
       indefinite length constructed encoding except in the case of signed
       data with detached content where the content is absent and DER format
       is used.

BUGS

       SMIME_write_CMS() always base64 encodes CMS structures, there should be
       an option to disable this.

RETURN VALUES

       SMIME_write_CMS() returns 1 for success or 0 for failure.

SEE ALSO

       ERR_get_error(3), CMS_sign(3), CMS_verify(3), CMS_encrypt(3)
       CMS_decrypt(3)

HISTORY

       SMIME_write_CMS() was added to OpenSSL 0.9.8

1.0.2t                            2019-09-10                SMIME_write_CMS(3)