=pod

=head1 NAME

SSL_set_initial_peer_addr - set the initial peer address for a QUIC connection

=head1 SYNOPSIS

 #include <openssl/ssl.h>

 int SSL_set_initial_peer_addr(SSL *s, const BIO_ADDR *addr);

=head1 DESCRIPTION

SSL_set_initial_peer_addr() sets the initial destination peer address to be used
for the purposes of establishing a QUIC connection in client mode. This function
can be used only on a QUIC connection SSL object, and can be used only before a
connection attempt is first made. I<addr> must point to a B<BIO_ADDR>
representing a UDP destination address of the server to connect to.

Where a QUIC connection object is provided with a write BIO which supports the
B<BIO_CTRL_DGRAM_GET_PEER> control (for example, B<BIO_s_dgram>), the initial
destination peer address can be detected automatically; if
B<BIO_CTRL_DGRAM_GET_PEER> returns a valid (non-B<AF_UNSPEC>) peer address and
no valid peer address has yet been set, this will be set automatically as the
initial peer address. This behaviour can be overridden by calling
SSL_set_initial_peer_addr() with a valid peer address explicitly.

The destination address used by QUIC may change over time in response to
connection events, such as connection migration (where supported).
SSL_set_initial_peer_addr() configures the destination address used for initial
connection establishment, and does not confer any guarantee about the
destination address being used for communication at any later time in the
connection lifecycle.

=head1 RETURN VALUES

Returns 1 on success and 0 on failure.

=head1 SEE ALSO

L<BIO_ADDR(3)>, L<ssl(7)>

=head1 HISTORY

The SSL_set_initial_peer_addr() function was added in OpenSSL 3.2.

=head1 COPYRIGHT

Copyright 2022 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