Placed API and implementation into separate packages
Change-Id: If8a9223a7a225db1b2aa2d09738857af482736bc
diff --git a/apps/cordvtn/src/main/java/org/onosproject/cordvtn/impl/RemoteIpCommandUtil.java b/apps/cordvtn/src/main/java/org/onosproject/cordvtn/impl/RemoteIpCommandUtil.java
new file mode 100644
index 0000000..c09e3a0
--- /dev/null
+++ b/apps/cordvtn/src/main/java/org/onosproject/cordvtn/impl/RemoteIpCommandUtil.java
@@ -0,0 +1,243 @@
+/*
+ * 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.cordvtn.impl;
+
+import com.google.common.collect.Sets;
+import com.google.common.io.CharStreams;
+import com.jcraft.jsch.Channel;
+import com.jcraft.jsch.ChannelExec;
+import com.jcraft.jsch.JSch;
+import com.jcraft.jsch.JSchException;
+import com.jcraft.jsch.Session;
+import org.onlab.packet.IpAddress;
+import org.onosproject.cordvtn.api.NetworkAddress;
+import org.onosproject.cordvtn.api.SshAccessInfo;
+import org.slf4j.Logger;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.Set;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * {@code RemoteIpCommandUtil} provides methods to help execute Linux IP commands to a remote server.
+ * It opens individual exec channels for each command. User can create a session with {@code connect}
+ * method and then execute a series commands. After done with all commands, the session must be closed
+ * explicitly by calling {@code disconnect}.
+ */
+public final class RemoteIpCommandUtil {
+
+ protected static final Logger log = getLogger(RemoteIpCommandUtil.class);
+
+ private static final String STRICT_HOST_CHECKING = "StrictHostKeyChecking";
+ private static final String DEFAULT_STRICT_HOST_CHECKING = "no";
+ private static final int DEFAULT_SESSION_TIMEOUT = 60000; // milliseconds
+
+ private static final String IP_PATTERN = "^([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\." +
+ "([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\." +
+ "([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\." +
+ "([01]?\\d\\d?|2[0-4]\\d|25[0-5])$";
+
+ private static final String IP_ADDR_SHOW = "sudo ip addr show %s";
+ private static final String IP_ADDR_FLUSH = "sudo ip addr flush %s";
+ private static final String IP_ADDR_ADD = "sudo ip addr add %s dev %s";
+ private static final String IP_ADDR_DELETE = "sudo ip addr delete %s dev %s";
+ private static final String IP_LINK_SHOW = "sudo ip link show %s";
+ private static final String IP_LINK_UP = "sudo ip link set %s up";
+
+ /**
+ * Default constructor.
+ */
+ private RemoteIpCommandUtil() {
+ }
+
+ /**
+ * Adds a given IP address to a given device.
+ *
+ * @param session ssh connection
+ * @param ip network address
+ * @param device device name to assign the ip address
+ * @return true if the command succeeds, or false
+ */
+ public static boolean addIp(Session session, NetworkAddress ip, String device) {
+ if (session == null || !session.isConnected()) {
+ return false;
+ }
+
+ executeCommand(session, String.format(IP_ADDR_ADD, ip.cidr(), device));
+ Set<IpAddress> result = getCurrentIps(session, device);
+ return result.contains(ip.ip());
+ }
+
+ /**
+ * Removes the IP address from a given device.
+ *
+ * @param session ssh connection
+ * @param ip ip address
+ * @param device device name
+ * @return true if the command succeeds, or false
+ */
+ public static boolean deleteIp(Session session, IpAddress ip, String device) {
+ if (session == null || !session.isConnected()) {
+ return false;
+ }
+
+ executeCommand(session, String.format(IP_ADDR_DELETE, ip, device));
+ Set<IpAddress> result = getCurrentIps(session, device);
+ return !result.contains(ip);
+ }
+
+ /**
+ * Removes all IP address on a given device.
+ *
+ * @param session ssh connection
+ * @param device device name
+ * @return true if the command succeeds, or false
+ */
+ public static boolean flushIp(Session session, String device) {
+ if (session == null || !session.isConnected()) {
+ return false;
+ }
+
+ executeCommand(session, String.format(IP_ADDR_FLUSH, device));
+ return getCurrentIps(session, device).isEmpty();
+ }
+
+ /**
+ * Returns a set of IP address that a given device has.
+ *
+ * @param session ssh connection
+ * @param device device name
+ * @return set of IP prefix or empty set
+ */
+ public static Set<IpAddress> getCurrentIps(Session session, String device) {
+ if (session == null || !session.isConnected()) {
+ return Sets.newHashSet();
+ }
+
+ String output = executeCommand(session, String.format(IP_ADDR_SHOW, device));
+ Set<IpAddress> result = Pattern.compile(" |/")
+ .splitAsStream(output)
+ .filter(s -> s.matches(IP_PATTERN))
+ .map(IpAddress::valueOf)
+ .collect(Collectors.toSet());
+
+ return result;
+ }
+
+ /**
+ * Sets link state up for a given device.
+ *
+ * @param session ssh connection
+ * @param device device name
+ * @return true if the command succeeds, or false
+ */
+ public static boolean setInterfaceUp(Session session, String device) {
+ if (session == null || !session.isConnected()) {
+ return false;
+ }
+
+ executeCommand(session, String.format(IP_LINK_UP, device));
+ return isInterfaceUp(session, device);
+ }
+
+ /**
+ * Checks if a given interface is up or not.
+ *
+ * @param session ssh connection
+ * @param device device name
+ * @return true if the interface is up, or false
+ */
+ public static boolean isInterfaceUp(Session session, String device) {
+ if (session == null || !session.isConnected()) {
+ return false;
+ }
+
+ String output = executeCommand(session, String.format(IP_LINK_SHOW, device));
+ return output != null && output.contains("UP");
+ }
+
+ /**
+ * Creates a new session with a given access information.
+ *
+ * @param sshInfo information to ssh to the remove server
+ * @return ssh session, or null
+ */
+ public static Session connect(SshAccessInfo sshInfo) {
+ try {
+ JSch jsch = new JSch();
+ jsch.addIdentity(sshInfo.privateKey());
+
+ Session session = jsch.getSession(sshInfo.user(),
+ sshInfo.remoteIp().toString(),
+ sshInfo.port().toInt());
+ session.setConfig(STRICT_HOST_CHECKING, DEFAULT_STRICT_HOST_CHECKING);
+ session.connect(DEFAULT_SESSION_TIMEOUT);
+
+ return session;
+ } catch (JSchException e) {
+ log.debug("Failed to connect to {} due to {}", sshInfo.toString(), e.toString());
+ return null;
+ }
+ }
+
+ /**
+ * Closes a connection.
+ *
+ * @param session session
+ */
+ public static void disconnect(Session session) {
+ if (session.isConnected()) {
+ session.disconnect();
+ }
+ }
+
+ /**
+ * Executes a given command. It opens exec channel for the command and closes
+ * the channel when it's done.
+ *
+ * @param session ssh connection to a remote server
+ * @param command command to execute
+ * @return command output string if the command succeeds, or null
+ */
+ private static String executeCommand(Session session, String command) {
+ if (session == null || !session.isConnected()) {
+ return null;
+ }
+
+ log.trace("Execute command {} to {}", command, session.getHost());
+
+ try {
+ Channel channel = session.openChannel("exec");
+ ((ChannelExec) channel).setCommand(command);
+ channel.setInputStream(null);
+ InputStream output = channel.getInputStream();
+
+ channel.connect();
+ String result = CharStreams.toString(new InputStreamReader(output));
+ channel.disconnect();
+
+ return result;
+ } catch (JSchException | IOException e) {
+ log.debug("Failed to execute command {} due to {}", command, e.toString());
+ return null;
+ }
+ }
+}