/*
protocol_subnet.c -- handle the meta-protocol, subnets
Copyright (C) 1999-2005 Ivo Timmermans,
2000-2009 Guus Sliepen <guus@tinc-vpn.org>
2009 Michael Tokarev <mjt@tls.msk.ru>
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 "net.h"
#include "netutl.h"
#include "node.h"
#include "protocol.h"
#include "subnet.h"
#include "utils.h"
#include "xalloc.h"
bool send_add_subnet(connection_t *c, const subnet_t *subnet) {
char netstr[MAXNETSTR];
if(!net2str(netstr, sizeof netstr, subnet))
return false;
return send_request(c, "%d %x %s %s", ADD_SUBNET, rand(), subnet->owner->name, netstr);
}
bool add_subnet_h(connection_t *c) {
char subnetstr[MAX_STRING_SIZE];
char name[MAX_STRING_SIZE];
node_t *owner;
subnet_t s = {0}, *new, *old;
if(sscanf(c->buffer, "%*d %*x " MAX_STRING " " MAX_STRING, name, subnetstr) != 2) {
logger(LOG_ERR, "Got bad %s from %s (%s)", "ADD_SUBNET", c->name,
c->hostname);
return false;
}
/* Check if owner name is valid */
if(!check_id(name)) {
logger(LOG_ERR, "Got bad %s from %s (%s): %s", "ADD_SUBNET", c->name,
c->hostname, "invalid name");
return false;
}
/* Check if subnet string is valid */
if(!str2net(&s, subnetstr)) {
logger(LOG_ERR, "Got bad %s from %s (%s): %s", "ADD_SUBNET", c->name,
c->hostname, "invalid subnet string");
return false;
}
if(seen_request(c->buffer))
return true;
/* Check if the owner of the new subnet is in the connection list */
owner = lookup_node(name);
if(tunnelserver && owner != myself && owner != c->node) {
/* in case of tunnelserver, ignore indirect subnet registrations */
ifdebug(PROTOCOL) logger(LOG_WARNING, "Ignoring indirect %s from %s (%s) for %s",
"ADD_SUBNET", c->name, c->hostname, subnetstr);
return true;
}
if(!owner) {
owner = new_node();
owner->name = xstrdup(name);
node_add(owner);
}
/* Check if we already know this subnet */
if(lookup_subnet(owner, &s))
return true;
/* If we don't know this subnet, but we are the owner, retaliate with a DEL_SUBNET */
if(owner == myself) {
ifdebug(PROTOCOL) logger(LOG_WARNING, "Got %s from %s (%s) for ourself",
"ADD_SUBNET", c->name, c->hostname);
s.owner = myself;
send_del_subnet(c, &s);
return true;
}
/* In tunnel server mode, we should already know all allowed subnets */
if(tunnelserver) {
logger(LOG_WARNING, "Ignoring unauthorized %s from %s (%s): %s",
"ADD_SUBNET", c->name, c->hostname, subnetstr);
return true;
}
/* Ignore if strictsubnets is true, but forward it to others */
if(strictsubnets) {
logger(LOG_WARNING, "Ignoring unauthorized %s from %s (%s): %s",
"ADD_SUBNET", c->name, c->hostname, subnetstr);
forward_request(c);
return true;
}
/* If everything is correct, add the subnet to the list of the owner */
*(new = new_subnet()) = s;
subnet_add(owner, new);
if(owner->status.reachable)
subnet_update(owner, new, true);
/* Tell the rest */
forward_request(c);
/* Fast handoff of roaming MAC addresses */
if(s.type == SUBNET_MAC && owner != myself && (old = lookup_subnet(myself, &s)) && old->expires)
old->expires = now;
return true;
}
bool send_del_subnet(connection_t *c, const subnet_t *s) {
char netstr[MAXNETSTR];
if(!net2str(netstr, sizeof netstr, s))
return false;
return send_request(c, "%d %x %s %s", DEL_SUBNET, rand(), s->owner->name, netstr);
}
bool del_subnet_h(connection_t *c) {
char subnetstr[MAX_STRING_SIZE];
char name[MAX_STRING_SIZE];
node_t *owner;
subnet_t s = {0}, *find;
if(sscanf(c->buffer, "%*d %*x " MAX_STRING " " MAX_STRING, name, subnetstr) != 2) {
logger(LOG_ERR, "Got bad %s from %s (%s)", "DEL_SUBNET", c->name,
c->hostname);
return false;
}
/* Check if owner name is valid */
if(!check_id(name)) {
logger(LOG_ERR, "Got bad %s from %s (%s): %s", "DEL_SUBNET", c->name,
c->hostname, "invalid name");
return false;
}
/* Check if subnet string is valid */
if(!str2net(&s, subnetstr)) {
logger(LOG_ERR, "Got bad %s from %s (%s): %s", "DEL_SUBNET", c->name,
c->hostname, "invalid subnet string");
return false;
}
if(seen_request(c->buffer))
return true;
/* Check if the owner of the subnet being deleted is in the connection list */
owner = lookup_node(name);
if(tunnelserver && owner != myself && owner != c->node) {
/* in case of tunnelserver, ignore indirect subnet deletion */
ifdebug(PROTOCOL) logger(LOG_WARNING, "Ignoring indirect %s from %s (%s) for %s",
"DEL_SUBNET", c->name, c->hostname, subnetstr);
return true;
}
if(!owner) {
ifdebug(PROTOCOL) logger(LOG_WARNING, "Got %s from %s (%s) for %s which is not in our node tree",
"DEL_SUBNET", c->name, c->hostname, name);
return true;
}
/* If everything is correct, delete the subnet from the list of the owner */
s.owner = owner;
find = lookup_subnet(owner, &s);
if(!find) {
ifdebug(PROTOCOL) logger(LOG_WARNING, "Got %s from %s (%s) for %s which does not appear in his subnet tree",
"DEL_SUBNET", c->name, c->hostname, name);
if(strictsubnets)
forward_request(c);
return true;
}
/* If we are the owner of this subnet, retaliate with an ADD_SUBNET */
if(owner == myself) {
ifdebug(PROTOCOL) logger(LOG_WARNING, "Got %s from %s (%s) for ourself",
"DEL_SUBNET", c->name, c->hostname);
send_add_subnet(c, find);
return true;
}
if(tunnelserver)
return true;
/* Tell the rest */
forward_request(c);
if(strictsubnets)
return true;
/* Finally, delete it. */
if(owner->status.reachable)
subnet_update(owner, find, false);
subnet_del(owner, find);
return true;
}