SSL_SET_BIO(3) OpenSSL SSL_SET_BIO(3)
NAME
SSL_set_bio, SSL_set0_rbio, SSL_set0_wbio - connect the SSL object with
a BIO
SYNOPSIS
#include <openssl/ssl.h>
void SSL_set_bio(SSL *ssl, BIO *rbio, BIO *wbio);
void SSL_set0_rbio(SSL *s, BIO *rbio);
void SSL_set0_wbio(SSL *s, BIO *wbio);
DESCRIPTION
SSL_set0_rbio() connects the BIO rbio for the read operations of the
ssl object. The SSL engine inherits the behaviour of rbio. If the BIO
is nonblocking then the ssl object will also have nonblocking
behaviour. This function transfers ownership of rbio to ssl. It will be
automatically freed using BIO_free_all(3) when the ssl is freed. On
calling this function, any existing rbio that was previously set will
also be freed via a call to BIO_free_all(3) (this includes the case
where the rbio is set to the same value as previously).
SSL_set0_wbio() works in the same as SSL_set0_rbio() except that it
connects the BIO wbio for the write operations of the ssl object. Note
that if the rbio and wbio are the same then SSL_set0_rbio() and
SSL_set0_wbio() each take ownership of one reference. Therefore, it may
be necessary to increment the number of references available using
BIO_up_ref(3) before calling the set0 functions.
SSL_set_bio() is similar to SSL_set0_rbio() and SSL_set0_wbio() except
that it connects both the rbio and the wbio at the same time, and
transfers the ownership of rbio and wbio to ssl according to the
following set of rules:
o If neither the rbio or wbio have changed from their previous values
then nothing is done.
o If the rbio and wbio parameters are different and both are different
to their previously set values then one reference is consumed for the
rbio and one reference is consumed for the wbio.
o If the rbio and wbio parameters are the same and the rbio is not the
same as the previously set value then one reference is consumed.
o If the rbio and wbio parameters are the same and the rbio is the same
as the previously set value, then no additional references are
consumed.
o If the rbio and wbio parameters are different and the rbio is the
same as the previously set value then one reference is consumed for
the wbio and no references are consumed for the rbio.
o If the rbio and wbio parameters are different and the wbio is the
same as the previously set value and the old rbio and wbio values
were the same as each other then one reference is consumed for the
rbio and no references are consumed for the wbio.
o If the rbio and wbio parameters are different and the wbio is the
same as the previously set value and the old rbio and wbio values
were different to each other then one reference is consumed for the
rbio and one reference is consumed for the wbio.
Because of this complexity, this function should be avoided; use
SSL_set0_rbio() and SSL_set0_wbio() instead.
RETURN VALUES
SSL_set_bio(), SSL_set0_rbio() and SSL_set0_wbio() cannot fail.
SEE ALSO
SSL_get_rbio(3), SSL_connect(3), SSL_accept(3), SSL_shutdown(3),
ssl(7), bio(7)
HISTORY
SSL_set0_rbio() and SSL_set0_wbio() were added in OpenSSL 1.1.0.
COPYRIGHT
Copyright 2000-2020 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>.
1.1.1k 2021-03-25 SSL_SET_BIO(3)