Refactor LISP package to separate ctrl interface and impl classes

Change-Id: I4e94ff54299e886cd0e8b3ce38591b0900290f54
diff --git a/protocols/lisp/ctl/src/main/java/org/onosproject/lisp/ctl/impl/LispMapServer.java b/protocols/lisp/ctl/src/main/java/org/onosproject/lisp/ctl/impl/LispMapServer.java
new file mode 100644
index 0000000..58792a2
--- /dev/null
+++ b/protocols/lisp/ctl/src/main/java/org/onosproject/lisp/ctl/impl/LispMapServer.java
@@ -0,0 +1,226 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.lisp.ctl.impl;
+
+import org.onlab.packet.IpAddress;
+import org.onosproject.lisp.msg.authentication.LispAuthenticationConfig;
+import org.onosproject.lisp.msg.protocols.DefaultLispInfoReply.DefaultInfoReplyBuilder;
+import org.onosproject.lisp.msg.protocols.DefaultLispInfoRequest.DefaultInfoRequestBuilder;
+import org.onosproject.lisp.msg.protocols.DefaultLispMapNotify.DefaultNotifyBuilder;
+import org.onosproject.lisp.msg.protocols.DefaultLispMapRegister.DefaultRegisterBuilder;
+import org.onosproject.lisp.msg.protocols.LispEidRecord;
+import org.onosproject.lisp.msg.protocols.LispInfoReply;
+import org.onosproject.lisp.msg.protocols.LispInfoReply.InfoReplyBuilder;
+import org.onosproject.lisp.msg.protocols.LispInfoRequest;
+import org.onosproject.lisp.msg.protocols.LispInfoRequest.InfoRequestBuilder;
+import org.onosproject.lisp.msg.protocols.LispMapNotify;
+import org.onosproject.lisp.msg.protocols.LispMapNotify.NotifyBuilder;
+import org.onosproject.lisp.msg.protocols.LispMapRegister;
+import org.onosproject.lisp.msg.protocols.LispMapRegister.RegisterBuilder;
+import org.onosproject.lisp.msg.protocols.LispMessage;
+import org.onosproject.lisp.msg.types.LispAfiAddress;
+import org.onosproject.lisp.msg.types.LispIpv4Address;
+import org.onosproject.lisp.msg.types.LispIpv6Address;
+import org.onosproject.lisp.msg.types.LispNatLcafAddress.NatAddressBuilder;
+import org.onosproject.lisp.msg.types.LispNoAddress;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.UnknownHostException;
+import java.util.Arrays;
+
+import static org.onosproject.lisp.msg.authentication.LispAuthenticationKeyEnum.valueOf;
+
+/**
+ * LISP map server class.
+ * Handles map-register message and acknowledges with map-notify message.
+ */
+public final class LispMapServer {
+
+    private static final int MAP_NOTIFY_PORT = 4342;
+    private static final int INFO_REPLY_PORT = 4342;
+
+    private static final Logger log = LoggerFactory.getLogger(LispMapServer.class);
+
+    private LispMappingDatabase mapDb = LispMappingDatabase.getInstance();
+    private LispAuthenticationConfig authConfig = LispAuthenticationConfig.getInstance();
+
+    // non-instantiable (except for our Singleton)
+    private LispMapServer() {
+    }
+
+    public static LispMapServer getInstance() {
+        return SingletonHelper.INSTANCE;
+    }
+
+    /**
+     * Handles map-register message and replies with map-notify message.
+     *
+     * @param message map-register message
+     * @return map-notify message
+     */
+    public LispMapNotify processMapRegister(LispMessage message) {
+
+        LispMapRegister register = (LispMapRegister) message;
+
+        if (!checkMapRegisterAuthData(register)) {
+            log.warn("Unmatched authentication data of Map-Register");
+            return null;
+        }
+
+        register.getMapRecords().forEach(mapRecord -> {
+            LispEidRecord eidRecord =
+                    new LispEidRecord(mapRecord.getMaskLength(),
+                                      mapRecord.getEidPrefixAfi());
+
+            mapDb.putMapRecord(eidRecord, mapRecord);
+        });
+
+        // we only acknowledge back to ETR when want-map-notify bit is set to true
+        // otherwise, we do not acknowledge back to ETR
+        if (register.isWantMapNotify()) {
+            NotifyBuilder notifyBuilder = new DefaultNotifyBuilder();
+            notifyBuilder.withKeyId(authConfig.lispAuthKeyId());
+            notifyBuilder.withAuthDataLength(valueOf(authConfig.lispAuthKeyId()).getHashLength());
+            notifyBuilder.withAuthKey(authConfig.lispAuthKey());
+            notifyBuilder.withNonce(register.getNonce());
+            notifyBuilder.withMapRecords(register.getMapRecords());
+
+            LispMapNotify notify = notifyBuilder.build();
+
+            InetSocketAddress address =
+                    new InetSocketAddress(register.getSender().getAddress(), MAP_NOTIFY_PORT);
+            notify.configSender(address);
+
+            return notify;
+        }
+
+        return null;
+    }
+
+    /**
+     * Handles info-request message and replies with info-reply message.
+     *
+     * @param message info-request message
+     * @return info-reply message
+     */
+    public LispInfoReply processInfoRequest(LispMessage message) {
+        LispInfoRequest request = (LispInfoRequest) message;
+
+        if (!checkInfoRequestAuthData(request)) {
+            log.warn("Unmatched authentication data of Info-Request");
+            return null;
+        }
+
+        NatAddressBuilder natBuilder = new NatAddressBuilder();
+        try {
+            LispAfiAddress msAddress =
+                    new LispIpv4Address(IpAddress.valueOf(InetAddress.getLocalHost()));
+            natBuilder.withMsRlocAddress(msAddress);
+            natBuilder.withMsUdpPortNumber((short) INFO_REPLY_PORT);
+
+            // try to extract global ETR RLOC address from info-request
+            IpAddress globalRlocIp = IpAddress.valueOf(request.getSender().getAddress());
+            LispAfiAddress globalRlocAddress;
+            if (globalRlocIp.isIp4()) {
+                globalRlocAddress = new LispIpv4Address(globalRlocIp);
+            } else {
+                globalRlocAddress = new LispIpv6Address(globalRlocIp);
+            }
+            natBuilder.withGlobalEtrRlocAddress(globalRlocAddress);
+            natBuilder.withEtrUdpPortNumber((short) request.getSender().getPort());
+            natBuilder.withPrivateEtrRlocAddress(new LispNoAddress());
+
+            // TODO: need to specify RTR addresses
+
+        } catch (UnknownHostException e) {
+            log.warn("Fails during formulate NAT address", e);
+        }
+
+        InfoReplyBuilder replyBuilder = new DefaultInfoReplyBuilder();
+        replyBuilder.withKeyId(request.getKeyId());
+        replyBuilder.withAuthDataLength(valueOf(authConfig.lispAuthKeyId()).getHashLength());
+        replyBuilder.withAuthKey(authConfig.lispAuthKey());
+        replyBuilder.withNonce(request.getNonce());
+        replyBuilder.withEidPrefix(request.getPrefix());
+        replyBuilder.withMaskLength(request.getMaskLength());
+        replyBuilder.withTtl(request.getTtl());
+        replyBuilder.withNatLcafAddress(natBuilder.build());
+        replyBuilder.withIsInfoReply(true);
+
+        LispInfoReply reply = replyBuilder.build();
+        reply.configSender(request.getSender());
+
+        return reply;
+    }
+
+    /**
+     * Checks the integrity of the received map-register message by calculating
+     * authentication data from received map-register message.
+     *
+     * @param register map-register message
+     * @return evaluation result
+     */
+    private boolean checkMapRegisterAuthData(LispMapRegister register) {
+        RegisterBuilder registerBuilder = new DefaultRegisterBuilder();
+        registerBuilder.withKeyId(register.getKeyId());
+        registerBuilder.withAuthKey(authConfig.lispAuthKey());
+        registerBuilder.withNonce(register.getNonce());
+        registerBuilder.withIsProxyMapReply(register.isProxyMapReply());
+        registerBuilder.withIsWantMapNotify(register.isWantMapNotify());
+        registerBuilder.withMapRecords(register.getMapRecords());
+
+        LispMapRegister authRegister = registerBuilder.build();
+
+        return Arrays.equals(authRegister.getAuthData(), register.getAuthData());
+    }
+
+    /**
+     * Checks the integrity of the received info-request message by calculating
+     * authentication data from received info-request message.
+     *
+     * @param request info-request message
+     * @return evaluation result
+     */
+    private boolean checkInfoRequestAuthData(LispInfoRequest request) {
+        InfoRequestBuilder requestBuilder = new DefaultInfoRequestBuilder();
+        requestBuilder.withKeyId(request.getKeyId());
+        requestBuilder.withAuthKey(authConfig.lispAuthKey());
+        requestBuilder.withNonce(request.getNonce());
+        requestBuilder.withTtl(request.getTtl());
+        requestBuilder.withEidPrefix(request.getPrefix());
+        requestBuilder.withIsInfoReply(request.isInfoReply());
+        requestBuilder.withMaskLength(request.getMaskLength());
+
+        LispInfoRequest authRequest = requestBuilder.build();
+
+        return Arrays.equals(authRequest.getAuthData(), request.getAuthData());
+    }
+
+    /**
+     * Prevents object instantiation from external.
+     */
+    private static final class SingletonHelper {
+        private static final String ILLEGAL_ACCESS_MSG = "Should not instantiate this class.";
+        private static final LispMapServer INSTANCE = new LispMapServer();
+
+        private SingletonHelper() {
+            throw new IllegalAccessError(ILLEGAL_ACCESS_MSG);
+        }
+    }
+}