/*
 *  OpenVPN -- An application to securely tunnel IP networks
 *             over a single TCP/UDP port, with support for SSL/TLS-based
 *             session authentication and key exchange,
 *             packet encryption, packet authentication, and
 *             packet compression.
 *
 *  Copyright (C) 2002-2018 OpenVPN Inc <sales@openvpn.net>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef FORWARD_INLINE_H
#define FORWARD_INLINE_H

/*
 * Inline functions
 */

/*
 * Does TLS session need service?
 */
static inline void
check_tls(struct context *c)
{
#if defined(ENABLE_CRYPTO)
    void check_tls_dowork(struct context *c);

    if (c->c2.tls_multi)
    {
        check_tls_dowork(c);
    }
#endif
}

/*
 * TLS errors are fatal in TCP mode.
 * Also check for --tls-exit trigger.
 */
static inline void
check_tls_errors(struct context *c)
{
#if defined(ENABLE_CRYPTO)
    void check_tls_errors_co(struct context *c);

    void check_tls_errors_nco(struct context *c);

    if (c->c2.tls_multi && c->c2.tls_exit_signal)
    {
        if (link_socket_connection_oriented(c->c2.link_socket))
        {
            if (c->c2.tls_multi->n_soft_errors)
            {
                check_tls_errors_co(c);
            }
        }
        else
        {
            if (c->c2.tls_multi->n_hard_errors)
            {
                check_tls_errors_nco(c);
            }
        }
    }
#endif /* if defined(ENABLE_CRYPTO) */
}

/*
 * Check for possible incoming configuration
 * messages on the control channel.
 */
static inline void
check_incoming_control_channel(struct context *c)
{
#if P2MP
    void check_incoming_control_channel_dowork(struct context *c);

    if (tls_test_payload_len(c->c2.tls_multi) > 0)
    {
        check_incoming_control_channel_dowork(c);
    }
#endif
}

/*
 * Options like --up-delay need to be triggered by this function which
 * checks for connection establishment.
 */
static inline void
check_connection_established(struct context *c)
{
    void check_connection_established_dowork(struct context *c);

    if (event_timeout_defined(&c->c2.wait_for_connect))
    {
        check_connection_established_dowork(c);
    }
}

/*
 * Should we add routes?
 */
static inline void
check_add_routes(struct context *c)
{
    void check_add_routes_dowork(struct context *c);

    if (event_timeout_trigger(&c->c2.route_wakeup, &c->c2.timeval, ETT_DEFAULT))
    {
        check_add_routes_dowork(c);
    }
}

/*
 * Should we exit due to inactivity timeout?
 */
static inline void
check_inactivity_timeout(struct context *c)
{
    void check_inactivity_timeout_dowork(struct context *c);

    if (c->options.inactivity_timeout
        && event_timeout_trigger(&c->c2.inactivity_interval, &c->c2.timeval, ETT_DEFAULT))
    {
        check_inactivity_timeout_dowork(c);
    }
}

#if P2MP

static inline void
check_server_poll_timeout(struct context *c)
{
    void check_server_poll_timeout_dowork(struct context *c);

    if (c->options.ce.connect_timeout
        && event_timeout_trigger(&c->c2.server_poll_interval, &c->c2.timeval, ETT_DEFAULT))
    {
        check_server_poll_timeout_dowork(c);
    }
}

/*
 * Scheduled exit?
 */
static inline void
check_scheduled_exit(struct context *c)
{
    void check_scheduled_exit_dowork(struct context *c);

    if (event_timeout_defined(&c->c2.scheduled_exit))
    {
        if (event_timeout_trigger(&c->c2.scheduled_exit, &c->c2.timeval, ETT_DEFAULT))
        {
            check_scheduled_exit_dowork(c);
        }
    }
}
#endif /* if P2MP */

/*
 * Should we write timer-triggered status file.
 */
static inline void
check_status_file(struct context *c)
{
    void check_status_file_dowork(struct context *c);

    if (c->c1.status_output)
    {
        if (status_trigger_tv(c->c1.status_output, &c->c2.timeval))
        {
            check_status_file_dowork(c);
        }
    }
}

#ifdef ENABLE_FRAGMENT
/*
 * Should we deliver a datagram fragment to remote?
 */
static inline void
check_fragment(struct context *c)
{
    void check_fragment_dowork(struct context *c);

    if (c->c2.fragment)
    {
        check_fragment_dowork(c);
    }
}
#endif

#if P2MP

/*
 * see if we should send a push_request in response to --pull
 */
static inline void
check_push_request(struct context *c)
{
    void check_push_request_dowork(struct context *c);

    if (event_timeout_trigger(&c->c2.push_request_interval, &c->c2.timeval, ETT_DEFAULT))
    {
        check_push_request_dowork(c);
    }
}

#endif

#ifdef ENABLE_CRYPTO
/*
 * Should we persist our anti-replay packet ID state to disk?
 */
static inline void
check_packet_id_persist_flush(struct context *c)
{
    if (packet_id_persist_enabled(&c->c1.pid_persist)
        && event_timeout_trigger(&c->c2.packet_id_persist_interval, &c->c2.timeval, ETT_DEFAULT))
    {
        packet_id_persist_save(&c->c1.pid_persist);
    }
}
#endif

/*
 * Set our wakeup to 0 seconds, so we will be rescheduled
 * immediately.
 */
static inline void
context_immediate_reschedule(struct context *c)
{
    c->c2.timeval.tv_sec = 0;  /* ZERO-TIMEOUT */
    c->c2.timeval.tv_usec = 0;
}

static inline void
context_reschedule_sec(struct context *c, int sec)
{
    if (sec < 0)
    {
        sec = 0;
    }
    if (sec < c->c2.timeval.tv_sec)
    {
        c->c2.timeval.tv_sec = sec;
        c->c2.timeval.tv_usec = 0;
    }
}

static inline struct link_socket_info *
get_link_socket_info(struct context *c)
{
    if (c->c2.link_socket_info)
    {
        return c->c2.link_socket_info;
    }
    else
    {
        return &c->c2.link_socket->info;
    }
}

static inline void
register_activity(struct context *c, const int size)
{
    if (c->options.inactivity_timeout)
    {
        c->c2.inactivity_bytes += size;
        if (c->c2.inactivity_bytes >= c->options.inactivity_minimum_bytes)
        {
            c->c2.inactivity_bytes = 0;
            event_timeout_reset(&c->c2.inactivity_interval);
        }
    }
}

/*
 * Return the io_wait() flags appropriate for
 * a point-to-point tunnel.
 */
static inline unsigned int
p2p_iow_flags(const struct context *c)
{
    unsigned int flags = (IOW_SHAPER|IOW_CHECK_RESIDUAL|IOW_FRAG|IOW_READ|IOW_WAIT_SIGNAL);
    if (c->c2.to_link.len > 0)
    {
        flags |= IOW_TO_LINK;
    }
    if (c->c2.to_tun.len > 0)
    {
        flags |= IOW_TO_TUN;
    }
    return flags;
}

/*
 * This is the core I/O wait function, used for all I/O waits except
 * for TCP in server mode.
 */
static inline void
io_wait(struct context *c, const unsigned int flags)
{
    void io_wait_dowork(struct context *c, const unsigned int flags);

    if (c->c2.fast_io && (flags & (IOW_TO_TUN|IOW_TO_LINK|IOW_MBUF)))
    {
        /* fast path -- only for TUN/TAP/UDP writes */
        unsigned int ret = 0;
        if (flags & IOW_TO_TUN)
        {
            ret |= TUN_WRITE;
        }
        if (flags & (IOW_TO_LINK|IOW_MBUF))
        {
            ret |= SOCKET_WRITE;
        }
        c->c2.event_set_status = ret;
    }
    else
    {
        /* slow path */
        io_wait_dowork(c, flags);
    }
}

#define CONNECTION_ESTABLISHED(c) (get_link_socket_info(c)->connection_established)

#endif /* EVENT_INLINE_H */