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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
commitf215e02bf85f68d3a6106c2a1f4f7f063f819064 (patch)
tree6bb5b92c046312c4e95ac2620b10ddf482d3fa8b /src/VBox/NetworkServices/Dhcpd/DHCPD.cpp
parentInitial commit. (diff)
downloadvirtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.tar.xz
virtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.zip
Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/VBox/NetworkServices/Dhcpd/DHCPD.cpp')
-rw-r--r--src/VBox/NetworkServices/Dhcpd/DHCPD.cpp420
1 files changed, 420 insertions, 0 deletions
diff --git a/src/VBox/NetworkServices/Dhcpd/DHCPD.cpp b/src/VBox/NetworkServices/Dhcpd/DHCPD.cpp
new file mode 100644
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+++ b/src/VBox/NetworkServices/Dhcpd/DHCPD.cpp
@@ -0,0 +1,420 @@
+/* $Id: DHCPD.cpp $ */
+/** @file
+ * DHCP server - protocol logic
+ */
+
+/*
+ * Copyright (C) 2017-2023 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.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, in version 3 of the
+ * License.
+ *
+ * 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, see <https://www.gnu.org/licenses>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+
+/*********************************************************************************************************************************
+* Header Files *
+*********************************************************************************************************************************/
+#include "DhcpdInternal.h"
+#include "DHCPD.h"
+#include "DhcpOptions.h"
+
+#include <iprt/message.h>
+
+
+DHCPD::DHCPD()
+ : m_pConfig(NULL), m_db()
+{
+}
+
+
+/**
+ * Initializes the DHCPD with the given config.
+ *
+ * @returns VBox status code.
+ * @param pConfig The configuration to use.
+ */
+int DHCPD::init(const Config *pConfig) RT_NOEXCEPT
+{
+ Assert(pConfig);
+ AssertReturn(!m_pConfig, VERR_INVALID_STATE);
+ m_pConfig = pConfig;
+
+ /* Load the lease database, ignoring most issues except being out of memory: */
+ int rc = m_db.init(pConfig);
+ if (RT_SUCCESS(rc))
+ {
+ rc = i_loadLeases();
+ if (rc != VERR_NO_MEMORY)
+ return VINF_SUCCESS;
+
+ DHCP_LOG_MSG_ERROR(("Ran out of memory loading leases from '%s'. Try rename or delete the file.\n",
+ pConfig->getLeasesFilename().c_str()));
+ }
+ return rc;
+}
+
+
+/**
+ * Load leases from pConfig->getLeasesFilename().
+ */
+int DHCPD::i_loadLeases() RT_NOEXCEPT
+{
+ return m_db.loadLeases(m_pConfig->getLeasesFilename());
+}
+
+
+/**
+ * Save the current leases to pConfig->getLeasesFilename(), doing expiry first.
+ *
+ * This is called after m_db is updated during a client request, so the on disk
+ * database is always up-to-date. This means it doesn't matter if we're
+ * terminated with extreme prejudice, and it allows Main to look up IP addresses
+ * for VMs.
+ *
+ * @throws nothing
+ */
+void DHCPD::i_saveLeases() RT_NOEXCEPT
+{
+ m_db.expire();
+ m_db.writeLeases(m_pConfig->getLeasesFilename());
+}
+
+
+/**
+ * Process a DHCP client message.
+ *
+ * Called by VBoxNetDhcpd::dhcp4Recv().
+ *
+ * @returns Pointer to DHCP reply (caller deletes this). NULL if no reply
+ * warranted or we're out of memory.
+ * @param req The client message.
+ * @throws nothing
+ */
+DhcpServerMessage *DHCPD::process(DhcpClientMessage &req) RT_NOEXCEPT
+{
+ /*
+ * Dump the package if release log level 3+1 are enable or if debug logging is
+ * enabled. We don't normally want to do this at the default log level, of course.
+ */
+ if ((LogRelIs3Enabled() && LogRelIsEnabled()) || LogIsEnabled())
+ req.dump();
+
+ /*
+ * Fend off requests that are not for us.
+ */
+ OptServerId sid(req);
+ if (sid.present() && sid.value().u != m_pConfig->getIPv4Address().u)
+ {
+ if (req.broadcasted() && req.messageType() == RTNET_DHCP_MT_REQUEST)
+ {
+ LogRel2(("Message is not for us, canceling any pending offer.\n"));
+ m_db.cancelOffer(req);
+ }
+ else
+ LogRel2(("Message is not for us.\n"));
+ return NULL;
+ }
+
+ /*
+ * Process it.
+ */
+ DhcpServerMessage *reply = NULL;
+
+ switch (req.messageType())
+ {
+ /*
+ * Requests that require server's reply.
+ */
+ case RTNET_DHCP_MT_DISCOVER:
+ try
+ {
+ reply = i_doDiscover(req);
+ }
+ catch (std::bad_alloc &)
+ {
+ LogRelFunc(("i_doDiscover threw bad_alloc\n"));
+ }
+ break;
+
+ case RTNET_DHCP_MT_REQUEST:
+ try
+ {
+ reply = i_doRequest(req);
+ }
+ catch (std::bad_alloc &)
+ {
+ LogRelFunc(("i_doRequest threw bad_alloc\n"));
+ }
+ break;
+
+ case RTNET_DHCP_MT_INFORM:
+ try
+ {
+ reply = i_doInform(req);
+ }
+ catch (std::bad_alloc &)
+ {
+ LogRelFunc(("i_doInform threw bad_alloc\n"));
+ }
+ break;
+
+ /*
+ * Requests that don't have a reply.
+ */
+ case RTNET_DHCP_MT_DECLINE:
+ i_doDecline(req);
+ break;
+
+ case RTNET_DHCP_MT_RELEASE:
+ i_doRelease(req);
+ break;
+
+ /*
+ * Unexpected or unknown message types.
+ */
+ case RTNET_DHCP_MT_OFFER:
+ LogRel2(("Ignoring unexpected message of type RTNET_DHCP_MT_OFFER!\n"));
+ break;
+ case RTNET_DHCP_MT_ACK:
+ LogRel2(("Ignoring unexpected message of type RTNET_DHCP_MT_ACK!\n"));
+ break;
+ case RTNET_DHCP_MT_NAC:
+ LogRel2(("Ignoring unexpected message of type RTNET_DHCP_MT_NAC!\n"));
+ break;
+ default:
+ LogRel2(("Ignoring unexpected message of unknown type: %d (%#x)!\n", req.messageType(), req.messageType()));
+ break;
+ }
+
+ return reply;
+}
+
+
+/**
+ * Internal helper.
+ *
+ * @throws std::bad_alloc
+ */
+DhcpServerMessage *DHCPD::i_createMessage(int type, const DhcpClientMessage &req)
+{
+ return new DhcpServerMessage(req, type, m_pConfig->getIPv4Address());
+}
+
+
+/**
+ * 4.3.1 DHCPDISCOVER message
+ *
+ * When a server receives a DHCPDISCOVER message from a client, the server
+ * chooses a network address for the requesting client. If no address is
+ * available, the server may choose to report the problem to the system
+ * administrator. If an address is available, the new address SHOULD be chosen
+ * as follows:
+ * - The client's current address as recorded in the client's current binding,
+ * ELSE
+ * - The client's previous address as recorded in the client's (now expired or
+ * released) binding, if that address is in the server's pool of available
+ * addresses and not already allocated, ELSE
+ * - The address requested in the 'Requested IP Address' option, if that
+ * address is valid and not already allocated, ELSE
+ * - A new address allocated from the server's pool of available addresses;
+ * the address is selected based on the subnet from which the message was
+ * received (if 'giaddr' is 0) or on the address of the relay agent that
+ * forwarded the message ('giaddr' when not 0).
+ *
+ * ...
+ *
+ * @throws std::bad_alloc
+ */
+DhcpServerMessage *DHCPD::i_doDiscover(const DhcpClientMessage &req)
+{
+ /** @todo
+ * XXX: TODO: Windows iSCSI initiator sends DHCPDISCOVER first and
+ * it has ciaddr filled. Shouldn't let it screw up the normal
+ * lease we already have for that client, but we should probably
+ * reply with a pro-forma offer.
+ */
+ if (req.ciaddr().u != 0)
+ return NULL;
+
+ Config::ConfigVec vecConfigs;
+ m_pConfig->getConfigsForClient(vecConfigs, req.clientId(), OptVendorClassId(req), OptUserClassId(req));
+
+ Binding *b = m_db.allocateBinding(req, vecConfigs);
+ if (b == NULL)
+ return NULL;
+
+ std::unique_ptr<DhcpServerMessage> reply;
+
+ bool fRapidCommit = OptRapidCommit(req).present();
+ if (!fRapidCommit)
+ {
+ reply.reset(i_createMessage(RTNET_DHCP_MT_OFFER, req));
+
+ if (b->state() < Binding::OFFERED)
+ b->setState(Binding::OFFERED);
+
+ /** @todo use small lease time internally to quickly free unclaimed offers? */
+ }
+ else
+ {
+ reply.reset(i_createMessage(RTNET_DHCP_MT_ACK, req));
+ reply->addOption(OptRapidCommit(true));
+
+ b->setState(Binding::ACKED);
+ if (!b->isFixed())
+ i_saveLeases();
+ }
+
+ reply->setYiaddr(b->addr());
+ reply->addOption(OptLeaseTime(b->leaseTime()));
+
+ OptParameterRequest optlist(req);
+ optmap_t replyOptions;
+ reply->addOptions(m_pConfig->getOptionsForClient(replyOptions, optlist, vecConfigs));
+
+ // reply->maybeUnicast(req); /** @todo XXX: we reject ciaddr != 0 above */
+ return reply.release();
+}
+
+
+/**
+ * 4.3.2 DHCPREQUEST message
+ *
+ * A DHCPREQUEST message may come from a client responding to a DHCPOFFER
+ * message from a server, from a client verifying a previously allocated IP
+ * address or from a client extending the lease on a network address. If the
+ * DHCPREQUEST message contains a 'server identifier' option, the message is in
+ * response to a DHCPOFFER message. Otherwise, the message is a request to
+ * verify or extend an existing lease. If the client uses a 'client identifier'
+ * in a DHCPREQUEST message, it MUST use that same 'client identifier' in all
+ * subsequent messages. If the client included a list of requested parameters in
+ * a DHCPDISCOVER message, it MUST include that list in all subsequent messages.
+ *
+ * ...
+ *
+ * @throws std::bad_alloc
+ */
+DhcpServerMessage *DHCPD::i_doRequest(const DhcpClientMessage &req)
+{
+ OptRequestedAddress reqAddr(req);
+ if (req.ciaddr().u != 0 && reqAddr.present() && reqAddr.value().u != req.ciaddr().u)
+ {
+ std::unique_ptr<DhcpServerMessage> nak(i_createMessage(RTNET_DHCP_MT_NAC, req));
+ nak->addOption(OptMessage("Requested address does not match ciaddr"));
+ return nak.release();
+ }
+
+ Config::ConfigVec vecConfigs;
+ m_pConfig->getConfigsForClient(vecConfigs, req.clientId(), OptVendorClassId(req), OptUserClassId(req));
+
+ Binding *b = m_db.allocateBinding(req, vecConfigs);
+ if (b == NULL)
+ {
+ return i_createMessage(RTNET_DHCP_MT_NAC, req);
+ }
+
+ std::unique_ptr<DhcpServerMessage> ack(i_createMessage(RTNET_DHCP_MT_ACK, req));
+
+ b->setState(Binding::ACKED);
+ if (!b->isFixed())
+ i_saveLeases();
+
+ ack->setYiaddr(b->addr());
+ ack->addOption(OptLeaseTime(b->leaseTime()));
+
+ OptParameterRequest optlist(req);
+ optmap_t replyOptions;
+ ack->addOptions(m_pConfig->getOptionsForClient(replyOptions, optlist, vecConfigs));
+
+ ack->maybeUnicast(req);
+ return ack.release();
+}
+
+
+/**
+ * 4.3.5 DHCPINFORM message
+ *
+ * The server responds to a DHCPINFORM message by sending a DHCPACK message
+ * directly to the address given in the 'ciaddr' field of the DHCPINFORM
+ * message. The server MUST NOT send a lease expiration time to the client and
+ * SHOULD NOT fill in 'yiaddr'. The server includes other parameters in the
+ * DHCPACK message as defined in section 4.3.1.
+ *
+ * @throws std::bad_alloc
+ */
+DhcpServerMessage *DHCPD::i_doInform(const DhcpClientMessage &req)
+{
+ if (req.ciaddr().u == 0)
+ return NULL;
+
+ OptParameterRequest optlist(req);
+ if (!optlist.present())
+ return NULL;
+
+ Config::ConfigVec vecConfigs;
+ optmap_t info;
+ m_pConfig->getOptionsForClient(info, optlist, m_pConfig->getConfigsForClient(vecConfigs, req.clientId(),
+ OptVendorClassId(req), OptUserClassId(req)));
+ if (info.empty())
+ return NULL;
+
+ std::unique_ptr<DhcpServerMessage> ack(i_createMessage(RTNET_DHCP_MT_ACK, req));
+ ack->addOptions(info);
+ ack->maybeUnicast(req);
+ return ack.release();
+}
+
+
+/**
+ * 4.3.3 DHCPDECLINE message
+ *
+ * If the server receives a DHCPDECLINE message, the client has discovered
+ * through some other means that the suggested network address is already in
+ * use. The server MUST mark the network address as not available and SHOULD
+ * notify the local system administrator of a possible configuration problem.
+ *
+ * @throws nothing
+ */
+DhcpServerMessage *DHCPD::i_doDecline(const DhcpClientMessage &req) RT_NOEXCEPT
+{
+ RT_NOREF(req);
+ return NULL;
+}
+
+
+/**
+ * 4.3.4 DHCPRELEASE message
+ *
+ * Upon receipt of a DHCPRELEASE message, the server marks the network address
+ * as not allocated. The server SHOULD retain a record of the client's
+ * initialization parameters for possible reuse in response to subsequent
+ * requests from the client.
+ *
+ * @throws nothing
+ */
+DhcpServerMessage *DHCPD::i_doRelease(const DhcpClientMessage &req) RT_NOEXCEPT
+{
+ if (req.ciaddr().u != 0)
+ {
+ bool fReleased = m_db.releaseBinding(req);
+ if (fReleased)
+ i_saveLeases();
+ }
+
+ return NULL;
+}