From a502d96a860456ec5e8c96761db70f7cabb74751 Mon Sep 17 00:00:00 2001
From: Paul Martin <paul@paulsputer.com>
Date: Sat, 30 Apr 2016 04:19:14 -0400
Subject: [PATCH] Merge pull request #1073 from gitblit/1062-DocEditorUpdates

---
 src/main/java/com/gitblit/transport/ssh/SshDaemon.java |  114 +++++++++++++++++++++++++++++++++++++++++++++-----------
 1 files changed, 91 insertions(+), 23 deletions(-)

diff --git a/src/main/java/com/gitblit/transport/ssh/SshDaemon.java b/src/main/java/com/gitblit/transport/ssh/SshDaemon.java
index 9628cb8..5a94c9a 100644
--- a/src/main/java/com/gitblit/transport/ssh/SshDaemon.java
+++ b/src/main/java/com/gitblit/transport/ssh/SshDaemon.java
@@ -16,16 +16,22 @@
 package com.gitblit.transport.ssh;
 
 import java.io.File;
+import java.io.FileOutputStream;
 import java.io.IOException;
+import java.io.OutputStreamWriter;
 import java.net.InetSocketAddress;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
 import java.text.MessageFormat;
 import java.util.concurrent.atomic.AtomicBoolean;
 
-import org.apache.sshd.SshServer;
 import org.apache.sshd.common.io.IoServiceFactoryFactory;
 import org.apache.sshd.common.io.mina.MinaServiceFactoryFactory;
 import org.apache.sshd.common.io.nio2.Nio2ServiceFactoryFactory;
-import org.apache.sshd.server.keyprovider.PEMGeneratorHostKeyProvider;
+import org.apache.sshd.common.util.SecurityUtils;
+import org.apache.sshd.server.SshServer;
+import org.apache.sshd.server.auth.CachingPublicKeyAuthenticator;
+import org.bouncycastle.openssl.PEMWriter;
 import org.eclipse.jgit.internal.JGitText;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -35,14 +41,14 @@
 import com.gitblit.Keys;
 import com.gitblit.manager.IGitblit;
 import com.gitblit.transport.ssh.commands.SshCommandFactory;
-import com.gitblit.utils.IdGenerator;
+import com.gitblit.utils.JnaUtils;
 import com.gitblit.utils.StringUtils;
+import com.gitblit.utils.WorkQueue;
+import com.google.common.io.Files;
 
 /**
  * Manager for the ssh transport. Roughly analogous to the
  * {@link com.gitblit.transport.git.GitDaemon} class.
- *
- * @author Eric Myhre
  *
  */
 public class SshDaemon {
@@ -61,8 +67,6 @@
 	 */
 	public static final int DEFAULT_PORT = 22;
 
-	private static final String HOST_KEY_STORE = "sshKeyStore.pem";
-
 	private final AtomicBoolean run;
 
 	private final IGitblit gitblit;
@@ -72,15 +76,32 @@
 	 * Construct the Gitblit SSH daemon.
 	 *
 	 * @param gitblit
+	 * @param workQueue
 	 */
-	public SshDaemon(IGitblit gitblit, IdGenerator idGenerator) {
+	public SshDaemon(IGitblit gitblit, WorkQueue workQueue) {
 		this.gitblit = gitblit;
 
 		IStoredSettings settings = gitblit.getSettings();
-		int port = settings.getInteger(Keys.git.sshPort, 0);
-		String bindInterface = settings.getString(Keys.git.sshBindInterface,
-				"localhost");
 
+		// Ensure that Bouncy Castle is our JCE provider
+		SecurityUtils.setRegisterBouncyCastle(true);
+		if (SecurityUtils.isBouncyCastleRegistered()) {
+			log.debug("BouncyCastle is registered as a JCE provider");
+		}
+
+		// Generate host RSA and DSA keypairs and create the host keypair provider
+		File rsaKeyStore = new File(gitblit.getBaseFolder(), "ssh-rsa-hostkey.pem");
+		File dsaKeyStore = new File(gitblit.getBaseFolder(), "ssh-dsa-hostkey.pem");
+		generateKeyPair(rsaKeyStore, "RSA", 2048);
+		generateKeyPair(dsaKeyStore, "DSA", 0);
+		FileKeyPairProvider hostKeyPairProvider = new FileKeyPairProvider();
+		hostKeyPairProvider.setFiles(new String [] { rsaKeyStore.getPath(), dsaKeyStore.getPath(), dsaKeyStore.getPath() });
+
+		// Client public key authenticator
+		SshKeyAuthenticator keyAuthenticator =
+				new SshKeyAuthenticator(gitblit.getPublicKeyManager(), gitblit);
+
+		// Configure the preferred SSHD backend
 		String sshBackendStr = settings.getString(Keys.git.sshBackend,
 				SshSessionBackend.NIO2.name());
 		SshSessionBackend backend = SshSessionBackend.valueOf(sshBackendStr);
@@ -89,6 +110,9 @@
 		    	? MinaServiceFactoryFactory.class.getName()
 		    	: Nio2ServiceFactoryFactory.class.getName());
 
+		// Create the socket address for binding the SSH server
+		int port = settings.getInteger(Keys.git.sshPort, 0);
+		String bindInterface = settings.getString(Keys.git.sshBindInterface, "");
 		InetSocketAddress addr;
 		if (StringUtils.isEmpty(bindInterface)) {
 			addr = new InetSocketAddress(port);
@@ -96,37 +120,48 @@
 			addr = new InetSocketAddress(bindInterface, port);
 		}
 
-		File hostKeyStore = new File(gitblit.getBaseFolder(), HOST_KEY_STORE);
-		CachingPublicKeyAuthenticator keyAuthenticator =
-				new CachingPublicKeyAuthenticator(gitblit.getPublicKeyManager(), gitblit);
-
+		// Create the SSH server
 		sshd = SshServer.setUpDefaultServer();
 		sshd.setPort(addr.getPort());
 		sshd.setHost(addr.getHostName());
-		sshd.setKeyPairProvider(new PEMGeneratorHostKeyProvider(hostKeyStore.getPath()));
-		sshd.setPublickeyAuthenticator(keyAuthenticator);
+		sshd.setKeyPairProvider(hostKeyPairProvider);
+		sshd.setPublickeyAuthenticator(new CachingPublicKeyAuthenticator(keyAuthenticator));
 		sshd.setPasswordAuthenticator(new UsernamePasswordAuthenticator(gitblit));
+		if (settings.getBoolean(Keys.git.sshWithKrb5, false)) {
+			sshd.setGSSAuthenticator(new SshKrbAuthenticator(settings, gitblit));
+		}
 		sshd.setSessionFactory(new SshServerSessionFactory());
 		sshd.setFileSystemFactory(new DisabledFilesystemFactory());
 		sshd.setTcpipForwardingFilter(new NonForwardingFilter());
-		sshd.setCommandFactory(new SshCommandFactory(gitblit, idGenerator));
+		sshd.setCommandFactory(new SshCommandFactory(gitblit, workQueue));
 		sshd.setShellFactory(new WelcomeShell(settings));
 
-		String version = Constants.getGitBlitVersion() + " (" + sshd.getVersion() + ")";
+		// Set the server id.  This can be queried with:
+		//   ssh-keyscan -t rsa,dsa -p 29418 localhost
+		String version = String.format("%s (%s-%s)", Constants.getGitBlitVersion().replace(' ', '_'),
+				sshd.getVersion(), sshBackendStr);
 		sshd.getProperties().put(SshServer.SERVER_IDENTIFICATION, version);
 
 		run = new AtomicBoolean(false);
 	}
 
 	public String formatUrl(String gituser, String servername, String repository) {
-		if (sshd.getPort() == DEFAULT_PORT) {
+		IStoredSettings settings = gitblit.getSettings();
+
+		int port = sshd.getPort();
+		int displayPort = settings.getInteger(Keys.git.sshAdvertisedPort, port);
+		String displayServername = settings.getString(Keys.git.sshAdvertisedHost, "");
+		if(displayServername.isEmpty()) {
+			displayServername = servername;
+		}
+		if (displayPort == DEFAULT_PORT) {
 			// standard port
-			return MessageFormat.format("{0}@{1}/{2}", gituser, servername,
+			return MessageFormat.format("ssh://{0}@{1}/{2}", gituser, displayServername,
 					repository);
 		} else {
 			// non-standard port
 			return MessageFormat.format("ssh://{0}@{1}:{2,number,0}/{3}",
-					gituser, servername, sshd.getPort(), repository);
+					gituser, displayServername, displayPort, repository);
 		}
 	}
 
@@ -168,9 +203,42 @@
 			try {
 				((SshCommandFactory) sshd.getCommandFactory()).stop();
 				sshd.stop();
-			} catch (InterruptedException e) {
+			} catch (IOException e) {
 				log.error("SSH Daemon stop interrupted", e);
 			}
 		}
 	}
+
+    private void generateKeyPair(File file, String algorithm, int keySize) {
+    	if (file.exists()) {
+    		return;
+    	}
+        try {
+            KeyPairGenerator generator = SecurityUtils.getKeyPairGenerator(algorithm);
+            if (keySize != 0) {
+            	generator.initialize(keySize);
+                log.info("Generating {}-{} SSH host keypair...", algorithm, keySize);
+            } else {
+                log.info("Generating {} SSH host keypair...", algorithm);
+            }
+            KeyPair kp = generator.generateKeyPair();
+
+            // create an empty file and set the permissions
+            Files.touch(file);
+            try {
+            	JnaUtils.setFilemode(file, JnaUtils.S_IRUSR | JnaUtils.S_IWUSR);
+            } catch (UnsatisfiedLinkError | UnsupportedOperationException e) {
+            	// Unexpected/Unsupported OS or Architecture
+            }
+
+            FileOutputStream os = new FileOutputStream(file);
+            PEMWriter w = new PEMWriter(new OutputStreamWriter(os));
+            w.writeObject(kp);
+            w.flush();
+            w.close();
+        } catch (Exception e) {
+            log.warn(MessageFormat.format("Unable to generate {0} keypair", algorithm), e);
+            return;
+        }
+    }
 }

--
Gitblit v1.9.1