1 files changed, 165 insertions, 0 deletions
diff --git a/src/bin/dhcp6/dhcp6to4_ipc.cc b/src/bin/dhcp6/dhcp6to4_ipc.cc
new file mode 100644
index 0000000..0bb73f2
--- /dev/null
+++ b/src/bin/dhcp6/dhcp6to4_ipc.cc
@@ -0,0 +1,165 @@
+// Copyright (C) 2015-2022 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 <util/buffer.h>
+#include <dhcp/iface_mgr.h>
+#include <dhcp/pkt6.h>
+#include <dhcpsrv/callout_handle_store.h>
+#include <dhcpsrv/cfgmgr.h>
+#include <dhcp6/dhcp6to4_ipc.h>
+#include <dhcp6/dhcp6_log.h>
+#include <dhcp6/ctrl_dhcp6_srv.h>
+#include <dhcp6/dhcp6_srv.h>
+#include <exceptions/exceptions.h>
+#include <hooks/callout_handle.h>
+#include <hooks/hooks_log.h>
+#include <hooks/hooks_manager.h>
+#include <stats/stats_mgr.h>
+
+using namespace std;
+using namespace isc::hooks;
+
+namespace isc {
+namespace dhcp {
+
+uint16_t Dhcp6to4Ipc::client_port = 0;
+
+Dhcp6to4Ipc::Dhcp6to4Ipc() : Dhcp4o6IpcBase() {}
+
+Dhcp6to4Ipc& Dhcp6to4Ipc::instance() {
+    static Dhcp6to4Ipc dhcp6to4_ipc;
+    return (dhcp6to4_ipc);
+}
+
+void Dhcp6to4Ipc::open() {
+    uint16_t port = CfgMgr::instance().getStagingCfg()->getDhcp4o6Port();
+    if (port == 0) {
+        Dhcp4o6IpcBase::close();
+        return;
+    }
+    if (port > 65534) {
+        isc_throw(OutOfRange, "DHCP4o6 port " << port);
+    }
+
+    int old_fd = socket_fd_;
+    socket_fd_ = Dhcp4o6IpcBase::open(port, ENDPOINT_TYPE_V6);
+    if ((old_fd == -1) && (socket_fd_ != old_fd)) {
+        IfaceMgr::instance().addExternalSocket(socket_fd_,
+                                               Dhcp6to4Ipc::handler);
+    }
+}
+
+void Dhcp6to4Ipc::handler(int /* fd */) {
+    Dhcp6to4Ipc& ipc = Dhcp6to4Ipc::instance();
+    Pkt6Ptr pkt;
+
+    try {
+        LOG_DEBUG(packet6_logger, DBG_DHCP6_DETAIL, DHCP6_DHCP4O6_RECEIVING);
+        // Receive message from IPC.
+        pkt = ipc.receive();
+
+        if (pkt) {
+            LOG_DEBUG(packet6_logger, DBG_DHCP6_BASIC, DHCP6_DHCP4O6_PACKET_RECEIVED)
+                .arg(static_cast<int>(pkt->getType()))
+                .arg(pkt->getRemoteAddr().toText())
+                .arg(pkt->getRemotePort())
+                .arg(pkt->getIface());
+        }
+    } catch (const std::exception& e) {
+        LOG_DEBUG(packet6_logger,DBG_DHCP6_DETAIL, DHCP6_DHCP4O6_RECEIVE_FAIL)
+            .arg(e.what());
+    }
+
+    if (!pkt) {
+        return;
+    }
+
+    // Should we check it is a DHCPV6_DHCPV4_RESPONSE?
+
+    // Handle relay port
+    uint16_t relay_port = Dhcpv6Srv::checkRelaySourcePort(pkt);
+
+    // The received message has been unpacked by the receive() function. This
+    // method could have modified the message so it's better to pack() it
+    // again because we'll be forwarding it to a client.
+    isc::util::OutputBuffer& buf = pkt->getBuffer();
+    buf.clear();
+    pkt->pack();
+
+    // Don't use getType(): get the message type from the buffer as we
+    // want to know if it is a relayed message (vs. internal message type).
+    // getType() always returns the type of internal message.
+    uint8_t msg_type = buf[0];
+    if (client_port) {
+        pkt->setRemotePort(client_port);
+    } else if ((msg_type == DHCPV6_RELAY_FORW) ||
+               (msg_type == DHCPV6_RELAY_REPL)) {
+        pkt->setRemotePort(relay_port ? relay_port : DHCP6_SERVER_PORT);
+    } else {
+        pkt->setRemotePort(DHCP6_CLIENT_PORT);
+    }
+
+    // Can't call the pkt6_send callout because we don't have the query
+    // From Dhcpv6Srv::processPacketBufferSend
+
+    try {
+        // Let's execute all callouts registered for buffer6_send
+        if (HooksManager::calloutsPresent(Dhcpv6Srv::getHookIndexBuffer6Send())) {
+            CalloutHandlePtr callout_handle = getCalloutHandle(pkt);
+
+            // Delete previously set arguments
+            callout_handle->deleteAllArguments();
+
+            // Use the RAII wrapper to make sure that the callout handle state is
+            // reset when this object goes out of scope. All hook points must do
+            // it to prevent possible circular dependency between the callout
+            // handle and its arguments.
+            ScopedCalloutHandleState callout_handle_state(callout_handle);
+
+            // Enable copying options from the packet within hook library.
+            ScopedEnableOptionsCopy<Pkt6> response6_options_copy(pkt);
+
+            // Pass incoming packet as argument
+            callout_handle->setArgument("response6", pkt);
+
+            // Call callouts
+            HooksManager::callCallouts(Dhcpv6Srv::getHookIndexBuffer6Send(),
+                                       *callout_handle);
+
+            // Callouts decided to skip the next processing step. The next
+            // processing step would be to parse the packet, so skip at this
+            // stage means drop.
+            if ((callout_handle->getStatus() == CalloutHandle::NEXT_STEP_SKIP) ||
+                (callout_handle->getStatus() == CalloutHandle::NEXT_STEP_DROP)) {
+                LOG_DEBUG(hooks_logger, DBG_DHCP6_HOOKS,
+                          DHCP6_HOOK_BUFFER_SEND_SKIP)
+                    .arg(pkt->getLabel());
+                return;
+            }
+
+            callout_handle->getArgument("response6", pkt);
+        }
+
+        LOG_DEBUG(packet6_logger, DBG_DHCP6_DETAIL_DATA, DHCP6_RESPONSE_DATA)
+            .arg(static_cast<int>(pkt->getType())).arg(pkt->toText());
+
+        // Forward packet to the client.
+        IfaceMgr::instance().send(pkt);
+
+        // Update statistics accordingly for sent packet.
+        Dhcpv6Srv::processStatsSent(pkt);
+
+    } catch (const std::exception& e) {
+        LOG_ERROR(packet6_logger, DHCP6_DHCP4O6_SEND_FAIL).arg(e.what());
+    }
+}
+
+} // namespace dhcp
+
+} // namespace isc
+