ISSUE-203 Add new SshWorker and Connector class

Utilizing sshj library for client-host communication.

bwreg-service/pom.xml

@@ -187,6 +187,13 @@
 			<scope>provided</scope>
 		</dependency>
 
+                <dependency>
+                 <groupId>org.bouncycastle</groupId>
+                 <artifactId>bcprov-jdk15on</artifactId>
+                 <version>1.69</version>
+                 <type>jar</type>
+                </dependency>
+
 		<dependency>
 			<groupId>org.apache.httpcomponents</groupId>
 			<artifactId>httpclient</artifactId>
@@ -282,6 +289,12 @@
 			<artifactId>mockito-core</artifactId>
 			<scope>test</scope>
 		</dependency>
+                <dependency>
+                    <groupId>com.hierynomus</groupId>
+                    <artifactId>sshj</artifactId>
+                    <version>0.32.0</version>
+                    <type>jar</type>
+                </dependency>
 	</dependencies>
 
 	<build>

bwreg-service/src/main/java/edu/kit/scc/webreg/service/ssh/SshConnector.java

+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package edu.kit.scc.webreg.service.ssh;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.util.concurrent.TimeUnit;
+import net.schmizz.sshj.SSHClient;
+import net.schmizz.sshj.connection.channel.direct.Session;
+import net.schmizz.sshj.connection.channel.direct.Session.Shell;
+/**
+ *
+ * @author bum-admin
+ */
+public class SshConnector {
+
+    private final SSHClient ssh = new SSHClient();
+
+    private String output;
+
+
+    /**
+    * escapeString()
+    *
+    * Escape a given String to make it safe to be printed or stored.
+    *
+    * @param s The input String.
+    * @return The escaped output String.
+    **/
+    public String escapeString(String s){
+      return s.replace("\\", "\\\\")
+              .replace("\t", "\\t")
+              .replace("\b", "\\b")
+              .replace("\n", "\\n")
+              .replace("\r", "\\r")
+              .replace("\f", "\\f")
+              .replace("\'", "\\'")
+              .replace("\"", "\\\"");
+    }
+
+    /**
+     * sendInput()
+     *
+     * Send command as input to the host's InputStream.
+     *
+     * @param command The input string to be streamed into the hosts InputStream.
+     * @param host The host address.
+     * @param user The user to connect to the host as.
+     * @param privateKeyFilepath The path to the private ssh key to authenticate with.
+     * @param privateKeyPassword The password for the private ssh key at privateKeyFilepath.
+     * @param knownHostsFilepath The path to the file containing known hosts to verify host with.
+     * @return Any output or errors from the host as a single string.
+     * @throws java.io.IOException
+    **/
+    public String sendInput(String command, String host, String user, String privateKeyFilepath, String privateKeyPassword, String knownHostsFilepath) throws IOException{
+
+        output = "";
+        if (privateKeyFilepath == null || privateKeyFilepath.isBlank())
+        {
+            if (knownHostsFilepath == null || knownHostsFilepath.isBlank())
+            {
+                ssh.loadKnownHosts();
+            }
+            else
+            {
+                ssh.loadKnownHosts(new File(knownHostsFilepath));
+            }
+
+            ssh.connect(host);
+
+            ssh.authPublickey(user);
+        }
+        else
+        {
+            if (knownHostsFilepath == null || knownHostsFilepath.isBlank())
+            {
+                ssh.loadKnownHosts(new File(privateKeyFilepath.substring(0,privateKeyFilepath.lastIndexOf("/")) + "/known_hosts"));
+            }
+            else
+            {
+                ssh.loadKnownHosts(new File(knownHostsFilepath));
+            }
+
+            ssh.connect(host);
+
+            if (privateKeyPassword == null || privateKeyPassword.isBlank())
+            {
+                ssh.authPublickey(user, privateKeyFilepath);
+            }
+            else
+            {
+                ssh.authPublickey(user, ssh.loadKeys(privateKeyFilepath, privateKeyPassword));
+            }
+        }
+
+        try (Session session = ssh.startSession(); Shell shl = session.startShell()) {
+            // thread to read the InputStream (host's STDOUT)
+            Thread t = new Thread() {
+                @Override
+                public void run() {
+                    try {
+                        InputStream in = shl.getInputStream();
+                        BufferedReader br = new BufferedReader(new InputStreamReader(in));
+                        String line;
+                        while ((line = br.readLine()) != null) {
+                            output += "[STDOUT] " + line + "\n";
+                        }
+                    } catch (Exception e) {
+                        output += e.getMessage();
+                    }
+                }
+            };
+            t.start();
+            // thread to read the ErrorStream (host's STDERR)
+            Thread err_t = new Thread() {
+                @Override
+                public void run() {
+                    try {
+                        InputStream in = shl.getErrorStream();
+                        BufferedReader br = new BufferedReader(new InputStreamReader(in));
+                        String line;
+                        while ((line = br.readLine()) != null) {
+                            output += "[STDERR] " + line + "\n";
+                        }
+                    } catch (Exception e) {
+                        output += e.getMessage();
+                    }
+                }
+            };
+            err_t.start();
+
+            byte[] data = command.getBytes();
+            try (OutputStream out = shl.getOutputStream()) {
+                out.write(data);
+                out.flush();
+            }
+            shl.join(5, TimeUnit.SECONDS);
+        } finally {
+            ssh.disconnect();
+            return output;
+        }
+    }
+
+    /**
+     * setPassword()
+     *
+     * Send a JSON string of the format '{ "username" : userName , "password" : userPassword }' to the host's InputStream.
+     *
+     * @param userName The name od the user.
+     * @param userPassword The password for the given userName.
+     * @param host The host address.
+     * @param user The user to connect to the host as.
+     * @param privateKeyFilepath The path to the private ssh key to authenticate with.
+     * @param privateKeyPassword The password for the private ssh key at privateKeyFilepath.
+     * @param knownHostsFilepath The path to the file containing known hosts to verify host with.
+     * @return Any output or errors from the host as a single string.
+     * @throws java.io.IOException
+    **/
+    public String setPassword (String userName, String userPassword, String host, String user, String privateKeyFilepath, String privateKeyPassword, String knownHostsFilepath) throws IOException
+    {
+        return sendInput("{ \"username\" : \"" + escapeString(userName) + "\" , \"password\" : \"" + escapeString(userPassword) + "\" }",
+                host, user, privateKeyFilepath, privateKeyPassword, knownHostsFilepath);
+    }
+}

bwreg-service/src/main/java/edu/kit/scc/webreg/service/ssh/SshWorker.java

+/*
+ * To change this license header, choose License Headers in Project Properties.
+ * To change this template file, choose Tools | Templates
+ * and open the template in the editor.
+ */
+package edu.kit.scc.webreg.service.ssh;
+
+import edu.kit.scc.webreg.audit.Auditor;
+import edu.kit.scc.webreg.exc.PropertyReaderException;
+import edu.kit.scc.webreg.exc.RegisterException;
+import edu.kit.scc.webreg.service.reg.ldap.LdapWorker;
+import edu.kit.scc.webreg.service.reg.ldap.PropertyReader;
+import java.io.IOException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Worker to perform various operations via SSH.
+ * Utilizes sshj library.
+ *
+ * @author bum-admin
+ */
+public class SshWorker {
+
+    private static Logger logger = LoggerFactory.getLogger(LdapWorker.class);
+    private Auditor auditor;
+
+    // sending commands/passwords to ssh host's input
+    private String sshHost; // host to connect to (required)
+    private String sshUser; // user to connect to the host as (required)
+    /*
+    private String sshInput; // the input to send to the host's stream (required)
+    private String ssh_input_username;
+    private String ssh_input_password;
+     */
+    private String sshKeyFilepath; // file path to the private ssh key (optional)
+    private String sshKeyPassword; // password for the private key (optional)
+    private String sshKnownHosts; // filepath to the known hosts file (optional)
+
+    SshWorker(PropertyReader prop, Auditor auditor) throws RegisterException {
+        this.auditor = auditor;
+        try {
+            sshHost = prop.readProp("ssh_host");
+            sshUser = prop.readProp("ssh_user");
+            sshKeyFilepath = prop.readPropOrNull("ssh_key_filepath");
+            sshKeyPassword = prop.readPropOrNull("ssh_key_password");
+            sshKnownHosts = prop.readPropOrNull("ssh_known_hosts");
+        } catch (PropertyReaderException e) {
+            throw new RegisterException(e);
+        }
+    }
+
+    public void setPassword(String uid, String password) throws RegisterException {
+        // send "{ username: uid, password: password }" to STDIN of sshHost
+        try {
+            String response = new SshConnector().setPassword(uid, password, sshHost, sshUser,
+                    sshKeyFilepath, sshKeyPassword, sshKnownHosts);
+			if (!response.isBlank()) {
+				if (response.contains("[STDERR]")) {
+					throw new IOException(response);
+				}
+				logger.info("Sending password to host response: {}", response);
+			}
+        } catch (IOException e) {
+			logger.error("IOExcetion happened in SSH Session", e);
+			String message = "FAILED: Sending password over SSH to " + sshHost
+				+ " as " + sshUser + " for user " + uid + ": " + e.getMessage();
+//            auditor.logAction("", "SEND PASSWORD USER", uid, "Send user password failed",
+//                    AuditStatus.FAIL);
+            throw new RegisterException(message);
+        }
+    }
+}