SSL: SSL_sendfile() support with kernel TLS. Requires OpenSSL 3.0 compiled with "enable-ktls" option. Further, KTLS needs to be enabled in kernel, and in OpenSSL, either via OpenSSL configuration file or with "ssl_conf_command Options KTLS;" in nginx configuration. On FreeBSD, kernel TLS is available starting with FreeBSD 13.0, and can be enabled with "sysctl kern.ipc.tls.enable=1" and "kldload ktls_ocf" to load a software backend, see man ktls(4) for details. On Linux, kernel TLS is available starting with kernel 4.13 (at least 5.2 is recommended), and needs kernel compiled with CONFIG_TLS=y (with CONFIG_TLS=m, which is used at least on Ubuntu 21.04 by default, the tls module needs to be loaded with "modprobe tls").

/*
 * Copyright (C) Roman Arutyunyan
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_PROXY_PROTOCOL_H_INCLUDED_
#define _NGX_PROXY_PROTOCOL_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


#define NGX_PROXY_PROTOCOL_MAX_HEADER  107


struct ngx_proxy_protocol_s {
    ngx_str_t           src_addr;
    ngx_str_t           dst_addr;
    in_port_t           src_port;
    in_port_t           dst_port;
};


u_char *ngx_proxy_protocol_read(ngx_connection_t *c, u_char *buf,
    u_char *last);
u_char *ngx_proxy_protocol_write(ngx_connection_t *c, u_char *buf,
    u_char *last);


#endif /* _NGX_PROXY_PROTOCOL_H_INCLUDED_ */