= nng_tls(5)
//
// Copyright 2019 Staysail Systems, Inc. <info@staysail.tech>
// Copyright 2018 Capitar IT Group BV <info@capitar.com>
// Copyright 2019 Devolutions <info@devolutions.net>
//
// This document is supplied under the terms of the MIT License, a
// copy of which should be located in the distribution where this
// file was obtained (LICENSE.txt).  A copy of the license may also be
// found online at https://opensource.org/licenses/MIT.
//

== NAME

nng_tls - TLS over TCP connection

== SYNOPSIS

[source, c]
----
#include <nng/nng.h>
#include <nng/supplemental/tls/tls.h>

typedef struct nng_tls_s nng_tls;
----

== DESCRIPTION

An `nng_tls` (((TLS connection))) represents a connected stream.
TLS stream objects can be used to send or receive data, and
provide transport level security via cryptography over a TCP connected
stream.

NOTE: The `nng_tls` object is used for raw TLS connections, and
should not be confused with a pipe object created using the
<<nng_tls.7#,nng_tls(7)>> transport.

TIP: Most NNG applications should not use this, but instead use the
<<nng_tls.7#,nng_tls(7)>> transport instead.

These objects are created either establishing an outgoing connection
with <<nng_tls_dialer_dial.3tls#,`nng_tls_dialer_dial()`>> or by
accepting in incoming connection with
<<nng_tls_listener_accept.3tls#,`nng_tls_listener_accept()`>>.

TLS connections are byte streams, and are "`reliable`" in that data
will not be delivered out of order, or with portions missing.

Data can be sent using <<nng_tls_send.3tls#,`nng_tls_send()`>> or
received with <<nng_tls_recv.3tls#,`nng_tls_recv()`>>.

When the connection is no longer needed, it should be freed with
<<nng_tls_free.3tls#,`nng_tls_free()`>>.

TIP: It is possible to close the connection, without freeing it, by
using <<nng_tls_close.3tls#,`nng_tls_close()`>>.

=== Options

The following options are applicable to TLS connections, and may be
accessed using the <<nng_tls_getopt.3tls#,`nng_tls_getopt()`>> and
<<nng_tls_setopt.3tls#,`nng_tls_setopt()`>> functions.

* <<nng_options.5#NNG_OPT_LOCADDR,`NNG_OPT_LOCADDR`>>
* <<nng_options.5#NNG_OPT_REMADDR,`NNG_OPT_REMADDR`>>
* <<nng_tcp_options.5#NNG_OPT_TCP_KEEPALIVE,`NNG_OPT_TCP_KEEPALIVE`>>
* <<nng_tcp_options.5#NNG_OPT_TCP_NO_DELAY,`NNG_OPT_TCP_NODELAY`>>
* <<nng_tls_options.5#NNG_OPT_TLS_VERIFIED,`NNG_OPT_TLS_VERIFIED`>>

Other platform specific options may be available as well.

== SEE ALSO

[.text-left]
<<libnng.3#,libnng(3)>>,
<<nng_tls_close.3tls#,nng_tls_close(3tls)>>,
<<nng_tls_dialer_dial.3tls#,nng_tls_dialer_dial(3tls)>>,
<<nng_tls_free.3tls#,nng_tls_free(3tls)>>,
<<nng_tls_getopt.3tls#,nng_tls_getopt(3tls)>>,
<<nng_tls_listener_accept.3tls#,nng_tls_listener_accept(3tls)>>,
<<nng_tls_recv.3tls#,nng_tls_recv(3tls)>>,
<<nng_tls_send.3tls#,nng_tls_send(3tls)>>,
<<nng_tls_setopt.3tls#,nng_tls_setopt(3tls)>>,
<<nng_options.5#,nng_options(5)>>,
<<nng_tls_options.5#,nng_tls_options(5)>>,
<<nng.7#,nng(7)>>