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/*
protocol_misc.c -- handle the meta-protocol, miscellaneous functions
Copyright (C) 1999-2005 Ivo Timmermans,
2000-2012 Guus Sliepen <guus@tinc-vpn.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
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.
*/
#include "system.h"
#include "conf.h"
#include "connection.h"
#include "logger.h"
#include "meta.h"
#include "net.h"
#include "netutl.h"
#include "protocol.h"
#include "utils.h"
int maxoutbufsize = 0;
bool send_ping(connection_t *c) {
c->status.pinged = true;
c->last_ping_time = now;
return send_request(c, "%d", PING);
}
bool ping_h(connection_t *c) {
return send_pong(c);
}
bool send_pong(connection_t *c) {
return send_request(c, "%d", PONG);
}
bool pong_h(connection_t *c) {
c->status.pinged = false;
/* Successful connection, reset timeout if this is an outgoing connection. */
if(c->outgoing) {
c->outgoing->timeout = 0;
c->outgoing->cfg = NULL;
if(c->outgoing->ai) {
freeaddrinfo(c->outgoing->ai);
}
c->outgoing->ai = NULL;
c->outgoing->aip = NULL;
}
return true;
}
/* Sending and receiving packets via TCP */
bool send_tcppacket(connection_t *c, const vpn_packet_t *packet) {
/* If there already is a lot of data in the outbuf buffer, discard this packet.
We use a very simple Random Early Drop algorithm. */
if(2.0 * c->outbuflen / (float)maxoutbufsize - 1 > (float)rand() / (float)RAND_MAX) {
return true;
}
if(!send_request(c, "%d %hd", PACKET, packet->len)) {
return false;
}
return send_meta(c, (char *)packet->data, packet->len) && flush_meta(c);
}
bool tcppacket_h(connection_t *c) {
length_t len;
if(sscanf(c->buffer, "%*d %hu", &len) != 1) {
logger(LOG_ERR, "Got bad %s from %s (%s)", "PACKET", c->name,
c->hostname);
return false;
}
/* Set reqlen to len, this will tell receive_meta() that a tcppacket is coming. */
c->tcplen = len;
return true;
}
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