mirror of
https://github.com/openssl/openssl.git
synced 2024-12-27 06:21:43 +08:00
de521629c1
Reviewed-by: Matt Caswell <matt@openssl.org> Reviewed-by: Tomas Mraz <tomas@openssl.org> (Merged from https://github.com/openssl/openssl/pull/20765)
128 lines
5.1 KiB
Plaintext
128 lines
5.1 KiB
Plaintext
=pod
|
|
|
|
=head1 NAME
|
|
|
|
SSL_set_default_stream_mode,
|
|
SSL_DEFAULT_STREAM_MODE_NONE, SSL_DEFAULT_STREAM_MODE_AUTO_BIDI,
|
|
SSL_DEFAULT_STREAM_MODE_AUTO_UNI - manage the default stream for a QUIC
|
|
connection
|
|
|
|
=head1 SYNOPSIS
|
|
|
|
#include <openssl/ssl.h>
|
|
|
|
#define SSL_DEFAULT_STREAM_MODE_NONE
|
|
#define SSL_DEFAULT_STREAM_MODE_AUTO_BIDI
|
|
#define SSL_DEFAULT_STREAM_MODE_AUTO_UNI
|
|
|
|
int SSL_set_default_stream_mode(SSL *conn, uint32_t mode);
|
|
|
|
=head1 DESCRIPTION
|
|
|
|
A QUIC connection SSL object may have a default stream attached to it. A default
|
|
stream is a QUIC stream to which calls to L<SSL_read(3)> and L<SSL_write(3)>
|
|
made on a QUIC connection SSL object are redirected. Default stream handling
|
|
allows legacy applications to use QUIC similarly to a traditional TLS
|
|
connection.
|
|
|
|
When not disabled, a default stream is automatically created on an outgoing
|
|
connection once L<SSL_read(3)> or L<SSL_write(3)> is called.
|
|
|
|
A QUIC stream must be explicitly designated as client-initiated or
|
|
server-initiated up front. This broadly corresponds to whether an application
|
|
protocol involves the client transmitting first, or the server transmitting
|
|
first. As such, if L<SSL_read(3)> is called first (before any call to
|
|
L<SSL_write(3)>) after establishing a connection, OpenSSL will wait for the
|
|
server to open the first server-initiated stream, and then bind this as the
|
|
default stream. Conversely, if L<SSL_write(3)> is called before any call to
|
|
L<SSL_read(3)>, OpenSSL assumes the client wishes to transmit first, creates a
|
|
client-initiated stream, and binds this as the default stream.
|
|
|
|
By default, the default stream created is bidirectional. If a unidirectional
|
|
stream is desired, or if the application wishes to disable default stream
|
|
functionality, SSL_set_default_stream_mode() (discussed below) can be used to
|
|
accomplish this.
|
|
|
|
When a QUIC connection SSL object has no default stream currently associated
|
|
with it, for example because default stream functionality was disabled, calls to
|
|
functions which require a stream on the QUIC connection SSL object (for example,
|
|
L<SSL_read(3)> and L<SSL_write(3)>) will fail.
|
|
|
|
It is recommended that new applications and applications which rely on multiple
|
|
streams forego use of the default stream functionality, which is intended for
|
|
legacy applications.
|
|
|
|
SSL_set_default_stream_mode() can be used to configure or disable default stream
|
|
handling. It can only be called on a QUIC connection SSL object prior to any
|
|
default stream being created. If used, it is recommended to call it immediately
|
|
after calling L<SSL_new(3)>, prior to initiating a connection. The argument
|
|
I<mode> may be one of the following options:
|
|
|
|
=over 4
|
|
|
|
=item SSL_DEFAULT_STREAM_MODE_AUTO_BIDI
|
|
|
|
This is the default setting. If L<SSL_write(3)> is called prior to any call to
|
|
L<SSL_read(3)>, a bidirectional client-initiated stream is created and bound as
|
|
the default stream. If L<SSL_read(3)> is called prior to any call to
|
|
L<SSL_write(3)>, OpenSSL waits for an incoming stream from the peer (causing
|
|
L<SSL_read(3)> to block if the connection is in blocking mode), and then binds
|
|
that stream as the default stream. Note that this incoming stream may be either
|
|
bidirectional or unidirectional; thus, this setting does not guarantee the
|
|
presence of a bidirectional stream when L<SSL_read(3)> is called first. To
|
|
determine the type of a stream after a call to L<SSL_read(3)>, use
|
|
L<SSL_get_stream_type(3)>.
|
|
|
|
=item SSL_DEFAULT_STREAM_MODE_AUTO_UNI
|
|
|
|
In this mode, if L<SSL_write(3)> is called prior to any call to L<SSL_read(3)>,
|
|
a unidirectional client-initiated stream is created and bound as the default
|
|
stream. The behaviour is otherwise identical to that of
|
|
B<SSL_DEFAULT_STREAM_MODE_AUTO_BIDI>. The behaviour when L<SSL_read(3)> is
|
|
called prior to any call to L<SSL_write(3)> is unchanged.
|
|
|
|
=item SSL_DEFAULT_STREAM_MODE_NONE
|
|
|
|
Default stream creation is inhibited. This is the recommended mode of operation.
|
|
L<SSL_read(3)> and L<SSL_write(3)> calls cannot be made on the QUIC connection
|
|
SSL object directly. You must obtain streams using L<SSL_new_stream(3)> or
|
|
L<SSL_accept_stream(3)> in order to communicate with the peer.
|
|
|
|
=back
|
|
|
|
A default stream will not be automatically created on a QUIC connection SSL
|
|
object if the default stream mode is set to B<SSL_DEFAULT_STREAM_MODE_NONE>.
|
|
|
|
L<SSL_set_incoming_stream_policy(3)> interacts significantly with the default
|
|
stream functionality.
|
|
|
|
=head1 RETURN VALUES
|
|
|
|
SSL_set_default_stream_mode() returns 1 on success and 0 on failure.
|
|
|
|
SSL_set_default_stream_mode() fails if it is called after a default stream has
|
|
already been established.
|
|
|
|
These functions fail if called on a QUIC stream SSL object or on a non-QUIC SSL
|
|
object.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<SSL_new_stream(3)>, L<SSL_accept_stream(3)>, L<SSL_free(3)>,
|
|
L<SSL_set_incoming_stream_policy(3)>
|
|
|
|
=head1 HISTORY
|
|
|
|
These functions were added in OpenSSL 3.2.
|
|
|
|
=head1 COPYRIGHT
|
|
|
|
Copyright 2002-2023 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
|
|
L<https://www.openssl.org/source/license.html>.
|
|
|
|
=cut
|