gnutls_transport_set_fastopen(3) — Linux manual page
gnutls_transport_set_fastopen(3) gnutls gnutls_transport_set_fastopen(3)
NAME
gnutls_transport_set_fastopen - API function
SYNOPSIS
#include <gnutls/socket.h>
void gnutls_transport_set_fastopen(gnutls_session_t session, int
fd, struct sockaddr * connect_addr, socklen_t connect_addrlen,
unsigned int flags);
ARGUMENTS
gnutls_session_t session
is a gnutls_session_t type.
int fd is the session's socket descriptor
struct sockaddr * connect_addr
is the address we want to connect to
socklen_t connect_addrlen
is the length of connect_addr
unsigned int flags
must be zero
DESCRIPTION
Enables TCP Fast Open (TFO) for the specified TLS client session.
That means that TCP connection establishment and the transmission
of the first TLS client hello packet are combined. The peer's
address must be specified in connect_addr and connect_addrlen
, and the socket specified by fd should not be connected.
TFO only works for TCP sockets of type AF_INET and AF_INET6. If
the OS doesn't support TCP fast open this function will result to
gnutls using connect() transparently during the first write.
NOTE
This function overrides all the transport callback functions. If
this is undesirable, TCP Fast Open must be implemented on the
user callback functions without calling this function. When using
this function, transport callbacks must not be set, and
gnutls_transport_set_ptr() or gnutls_transport_set_int() must not
be called.
On GNU/Linux TFO has to be enabled at the system layer, that is
in /proc/sys/net/ipv4/tcp_fastopen, bit 0 has to be set.
This function has no effect on server sessions.
SINCE
3.5.3
REPORTING BUGS
Report bugs to <bugs@gnutls.org>.
Home page: https://www.gnutls.org
COPYRIGHT
Copyright © 2001-2023 Free Software Foundation, Inc., and others.
Copying and distribution of this file, with or without
modification, are permitted in any medium without royalty
provided the copyright notice and this notice are preserved.
SEE ALSO
The full documentation for gnutls is maintained as a Texinfo
manual. If the /usr/share/doc/gnutls/ directory does not contain
the HTML form visit
https://www.gnutls.org/manual/
COLOPHON
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Library) project. Information about the project can be found at
⟨http://www.gnutls.org/⟩. If you have a bug report for this
manual page, send it to bugs@gnutls.org. This page was obtained
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⟨http://www.gnutls.org/download.html⟩ on 2024-06-14. If you
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