SMIME_write_PKCS7 -- convert PKCS#7 structure to S/MIME format.
Synopsis
#include <openssl/pkcs7.h>
int SMIME_write_PKCS7(BIO *out, PKCS7 *p7, BIO *data, int flags);
DESCRIPTION
SMIME_write_PKCS7() adds the appropriate MIME headers to a PKCS#7
structure to produce an S/MIME message.
out is the BIO to write the data to.
p7 is the appropriate PKCS7 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 PKCS7_DETACHED is set then
cleartext signing will be used, this option only makes sense for
signedData where PKCS7_DETACHED is
also set when PKCS7_sign() is also called.
If the PKCS7_TEXT flag is set MIME
headers for type text/plain are
added to the content, this only makes sense if PKCS7_DETACHED is also set.
If the PKCS7_STREAM flag is set
streaming is performed. This flag should only be set if PKCS7_STREAM was also set in the previous call
to PKCS7_sign() or PKCS7_encrypt().
If cleartext signing is being used and PKCS7_STREAM not set then the data must be
read twice: once to compute the signature in PKCS7_sign() and once to
output the S/MIME message.
If streaming is performed the content is output in BER format using
indefinite length constructuted encoding except in the case of signed
data with detached content where the content is absent and DER format
is used.
BUGS
SMIME_write_PKCS7() always base64 encodes PKCS#7 structures, there
should be an option to disable this.
RETURN VALUES
SMIME_write_PKCS7() returns 1 for success or 0 for failure.
