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// Copyright (C) 2014-2017 Internet Systems Consortium, Inc. ("ISC")
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
#include <config.h>
#include <dhcp/iface_mgr.h>
#include <dhcpsrv/cfg_subnets4.h>
#include <dhcpsrv/dhcpsrv_log.h>
#include <dhcpsrv/lease_mgr_factory.h>
#include <dhcpsrv/subnet_id.h>
#include <dhcpsrv/addr_utilities.h>
#include <asiolink/io_address.h>
#include <stats/stats_mgr.h>
#include <sstream>
using namespace isc::asiolink;
using namespace isc::data;
namespace isc {
namespace dhcp {
void
CfgSubnets4::add(const Subnet4Ptr& subnet) {
if (getBySubnetId(subnet->getID())) {
isc_throw(isc::dhcp::DuplicateSubnetID, "ID of the new IPv4 subnet '"
<< subnet->getID() << "' is already in use");
} else if (getByPrefix(subnet->toText())) {
/// @todo: Check that this new subnet does not cross boundaries of any
/// other already defined subnet.
isc_throw(isc::dhcp::DuplicateSubnetID, "subnet with the prefix of '"
<< subnet->toText() << "' already exists");
}
LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE, DHCPSRV_CFGMGR_ADD_SUBNET4)
.arg(subnet->toText());
subnets_.push_back(subnet);
}
void
CfgSubnets4::del(const ConstSubnet4Ptr& subnet) {
auto& index = subnets_.get<SubnetIdIndexTag>();
auto subnet_it = index.find(subnet->getID());
if (subnet_it == index.end()) {
isc_throw(BadValue, "no subnet with ID of '" << subnet->getID()
<< "' found");
}
index.erase(subnet_it);
LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE, DHCPSRV_CFGMGR_DEL_SUBNET4)
.arg(subnet->toText());
}
ConstSubnet4Ptr
CfgSubnets4::getBySubnetId(const SubnetID& subnet_id) const {
const auto& index = subnets_.get<SubnetSubnetIdIndexTag>();
auto subnet_it = index.find(subnet_id);
return ((subnet_it != index.cend()) ? (*subnet_it) : ConstSubnet4Ptr());
}
ConstSubnet4Ptr
CfgSubnets4::getByPrefix(const std::string& subnet_text) const {
const auto& index = subnets_.get<SubnetPrefixIndexTag>();
auto subnet_it = index.find(subnet_text);
return ((subnet_it != index.cend()) ? (*subnet_it) : ConstSubnet4Ptr());
}
Subnet4Ptr
CfgSubnets4::selectSubnet4o6(const SubnetSelector& selector) const {
for (Subnet4Collection::const_iterator subnet = subnets_.begin();
subnet != subnets_.end(); ++subnet) {
Cfg4o6& cfg4o6 = (*subnet)->get4o6();
// Is this an 4o6 subnet at all?
if (!cfg4o6.enabled()) {
continue; // No? Let's try the next one.
}
// First match criteria: check if we have a prefix/len defined.
std::pair<asiolink::IOAddress, uint8_t> pref = cfg4o6.getSubnet4o6();
if (!pref.first.isV6Zero()) {
// Let's check if the IPv6 address is in range
IOAddress first = firstAddrInPrefix(pref.first, pref.second);
IOAddress last = lastAddrInPrefix(pref.first, pref.second);
if ((first <= selector.remote_address_) &&
(selector.remote_address_ <= last)) {
return (*subnet);
}
}
// Second match criteria: check if the interface-id matches
if (cfg4o6.getInterfaceId() && selector.interface_id_ &&
cfg4o6.getInterfaceId()->equals(selector.interface_id_)) {
return (*subnet);
}
// Third match criteria: check if the interface name matches
if (!cfg4o6.getIface4o6().empty() && !selector.iface_name_.empty()
&& cfg4o6.getIface4o6() == selector.iface_name_) {
return (*subnet);
}
}
// Ok, wasn't able to find any matching subnet.
return (Subnet4Ptr());
}
Subnet4Ptr
CfgSubnets4::selectSubnet(const SubnetSelector& selector) const {
// First use RAI link select sub-option or subnet select option
if (!selector.option_select_.isV4Zero()) {
return (selectSubnet(selector.option_select_,
selector.client_classes_));
}
// If relayed message has been received, try to match the giaddr with the
// relay address specified for a subnet. It is also possible that the relay
// address will not match with any of the relay addresses across all
// subnets, but we need to verify that for all subnets before we can try
// to use the giaddr to match with the subnet prefix.
if (!selector.giaddr_.isV4Zero()) {
for (Subnet4Collection::const_iterator subnet = subnets_.begin();
subnet != subnets_.end(); ++subnet) {
// Check if the giaddr is equal to the one defined for the subnet.
if (selector.giaddr_ != (*subnet)->getRelayInfo().addr_) {
continue;
}
// If a subnet meets the client class criteria return it.
if ((*subnet)->clientSupported(selector.client_classes_)) {
return (*subnet);
}
}
}
// If we got to this point it means that we were not able to match the
// giaddr with any of the addresses specified for subnets. Let's determine
// what address from the client's packet to use to match with the
// subnets' prefixes.
IOAddress address = IOAddress::IPV4_ZERO_ADDRESS();
// If there is a giaddr, use it for subnet selection.
if (!selector.giaddr_.isV4Zero()) {
address = selector.giaddr_;
// If it is a Renew or Rebind, use the ciaddr.
} else if (!selector.ciaddr_.isV4Zero() &&
!selector.local_address_.isV4Bcast()) {
address = selector.ciaddr_;
// If ciaddr is not specified, use the source address.
} else if (!selector.remote_address_.isV4Zero() &&
!selector.local_address_.isV4Bcast()) {
address = selector.remote_address_;
// If local interface name is known, use the local address on this
// interface.
} else if (!selector.iface_name_.empty()) {
IfacePtr iface = IfaceMgr::instance().getIface(selector.iface_name_);
// This should never happen in the real life. Hence we throw an
// exception.
if (iface == NULL) {
isc_throw(isc::BadValue, "interface " << selector.iface_name_
<< " doesn't exist and therefore it is impossible"
" to find a suitable subnet for its IPv4 address");
}
// Attempt to select subnet based on the interface name.
Subnet4Ptr subnet = selectSubnet(selector.iface_name_,
selector.client_classes_);
// If it matches - great. If not, we'll try to use a different
// selection criteria below.
if (subnet) {
return (subnet);
} else {
// Let's try to get an address from the local interface and
// try to match it to defined subnet.
iface->getAddress4(address);
}
}
// Unable to find a suitable address to use for subnet selection.
if (address.isV4Zero()) {
return (Subnet4Ptr());
}
// We have identified an address in the client's packet that can be
// used for subnet selection. Match this packet with the subnets.
return (selectSubnet(address, selector.client_classes_));
}
Subnet4Ptr
CfgSubnets4::selectSubnet(const std::string& iface,
const ClientClasses& client_classes) const {
for (Subnet4Collection::const_iterator subnet = subnets_.begin();
subnet != subnets_.end(); ++subnet) {
// If there's no interface specified for this subnet, proceed to
// the next subnet.
if ((*subnet)->getIface().empty()) {
continue;
}
// If it's specified, but does not match, proceed to the next
// subnet.
if ((*subnet)->getIface() != iface) {
continue;
}
// If a subnet meets the client class criteria return it.
if ((*subnet)->clientSupported(client_classes)) {
LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE,
DHCPSRV_CFGMGR_SUBNET4_IFACE)
.arg((*subnet)->toText())
.arg(iface);
return (*subnet);
}
}
// Failed to find a subnet.
return (Subnet4Ptr());
}
Subnet4Ptr
CfgSubnets4::getSubnet(const SubnetID id) const {
/// @todo: Once this code is migrated to multi-index container, use
/// an index rather than full scan.
for (auto subnet = subnets_.begin(); subnet != subnets_.end(); ++subnet) {
if ((*subnet)->getID() == id) {
return (*subnet);
}
}
return (Subnet4Ptr());
}
Subnet4Ptr
CfgSubnets4::selectSubnet(const IOAddress& address,
const ClientClasses& client_classes) const {
for (Subnet4Collection::const_iterator subnet = subnets_.begin();
subnet != subnets_.end(); ++subnet) {
// Address is in range for the subnet prefix, so return it.
if (!(*subnet)->inRange(address)) {
continue;
}
// If a subnet meets the client class criteria return it.
if ((*subnet)->clientSupported(client_classes)) {
LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE, DHCPSRV_CFGMGR_SUBNET4_ADDR)
.arg((*subnet)->toText())
.arg(address.toText());
return (*subnet);
}
}
// Failed to find a subnet.
return (Subnet4Ptr());
}
void
CfgSubnets4::removeStatistics() {
using namespace isc::stats;
// For each v4 subnet currently configured, remove the statistic.
StatsMgr& stats_mgr = StatsMgr::instance();
for (Subnet4Collection::const_iterator subnet4 = subnets_.begin();
subnet4 != subnets_.end(); ++subnet4) {
SubnetID subnet_id = (*subnet4)->getID();
stats_mgr.del(StatsMgr::generateName("subnet", subnet_id,
"total-addresses"));
stats_mgr.del(StatsMgr::generateName("subnet", subnet_id,
"assigned-addresses"));
stats_mgr.del(StatsMgr::generateName("subnet", subnet_id,
"declined-addresses"));
stats_mgr.del(StatsMgr::generateName("subnet", subnet_id,
"declined-reclaimed-addresses"));
stats_mgr.del(StatsMgr::generateName("subnet", subnet_id,
"reclaimed-leases"));
}
}
void
CfgSubnets4::updateStatistics() {
using namespace isc::stats;
StatsMgr& stats_mgr = StatsMgr::instance();
for (Subnet4Collection::const_iterator subnet4 = subnets_.begin();
subnet4 != subnets_.end(); ++subnet4) {
SubnetID subnet_id = (*subnet4)->getID();
stats_mgr.setValue(StatsMgr::
generateName("subnet", subnet_id, "total-addresses"),
static_cast<int64_t>
((*subnet4)->getPoolCapacity(Lease::
TYPE_V4)));
}
// Only recount the stats if we have subnets.
if (subnets_.begin() != subnets_.end()) {
LeaseMgrFactory::instance().recountLeaseStats4();
}
}
ElementPtr
CfgSubnets4::toElement() const {
ElementPtr result = Element::createList();
// Iterate subnets
for (Subnet4Collection::const_iterator subnet = subnets_.cbegin();
subnet != subnets_.cend(); ++subnet) {
result->add((*subnet)->toElement());
}
return (result);
}
} // end of namespace isc::dhcp
} // end of namespace isc
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