Add --ssh option to command-line commands

Enables using the new ssh client based on Apache MINA sshd instead
of the old JSch client. The default is still JSch, so unless the
command is invoked with --ssh apache, there's no change.

I prefer this over some fiddling with the GIT_SSH environment variable
since that variable is handled in the JGit core bundle, which should
remain free of any dependency to org.eclipse.jgit.ssh.apache to avoid
problems in Gerrit or other JGit users that may use a different Apache
MINA sshd version.

Bug: 520927
Change-Id: I8460759c7113ef7887520fb0d297aa312200c69f
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

org.eclipse.jgit.packaging/org.eclipse.jgit.pgm.feature/feature.xml

@@ -33,6 +33,7 @@
    <requires>
       <import feature="org.eclipse.jgit" version="5.2.0" match="equivalent"/>
       <import feature="org.eclipse.jgit.lfs" version="5.2.0" match="equivalent"/>
+      <import feature="org.eclipse.jgit.ssh.apache" version="5.2.0" match="equivalent"/>
    </requires>
 
    <plugin

org.eclipse.jgit.pgm/BUILD

@@ -23,6 +23,7 @@ java_library(
         "//org.eclipse.jgit.lfs:jgit-lfs",
         "//org.eclipse.jgit.lfs.server:jgit-lfs-server",
         "//org.eclipse.jgit.ui:ui",
+        "//org.eclipse.jgit.ssh.apache:ssh-apache",
     ],
 )
 

org.eclipse.jgit.pgm/META-INF/MANIFEST.MF

@@ -61,6 +61,7 @@ Import-Package: javax.servlet;version="[3.1.0,4.0.0)",
  org.eclipse.jgit.transport;version="[5.2.0,5.3.0)",
  org.eclipse.jgit.transport.http.apache;version="[5.2.0,5.3.0)",
  org.eclipse.jgit.transport.resolver;version="[5.2.0,5.3.0)",
+ org.eclipse.jgit.transport.sshd;version="[5.2.0,5.3.0)",
  org.eclipse.jgit.treewalk;version="[5.2.0,5.3.0)",
  org.eclipse.jgit.treewalk.filter;version="[5.2.0,5.3.0)",
  org.eclipse.jgit.util;version="[5.2.0,5.3.0)",

org.eclipse.jgit.pgm/pom.xml

@@ -100,6 +100,12 @@
       <version>${project.version}</version>
     </dependency>
 
+    <dependency>
+      <groupId>org.eclipse.jgit</groupId>
+      <artifactId>org.eclipse.jgit.ssh.apache</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+
     <dependency>
       <groupId>org.apache.httpcomponents</groupId>
       <artifactId>httpclient</artifactId>

org.eclipse.jgit.pgm/resources/org/eclipse/jgit/pgm/internal/CLIText.properties

@@ -402,6 +402,7 @@ usage_showNotes=Add this ref to the list of note branches from which notes are d
 usage_showTimeInMilliseconds=Show mtime in milliseconds
 usage_squash=Squash commits as if a real merge happened, but do not make a commit or move the HEAD.
 usage_srcPrefix=show the source prefix instead of "a/"
+usage_sshDriver=Selects the built-in ssh library to use, JSch or Apache MINA sshd.
 usage_symbolicVersionForTheProject=Symbolic version for the project
 usage_tags=fetch all tags
 usage_notags=do not fetch tags

org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/TextBuiltin.java

@@ -66,8 +66,12 @@ import java.util.ResourceBundle;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.pgm.internal.CLIText;
+import org.eclipse.jgit.pgm.internal.SshDriver;
 import org.eclipse.jgit.pgm.opt.CmdLineParser;
 import org.eclipse.jgit.revwalk.RevWalk;
+import org.eclipse.jgit.transport.SshSessionFactory;
+import org.eclipse.jgit.transport.sshd.JGitKeyCache;
+import org.eclipse.jgit.transport.sshd.SshdSessionFactory;
 import org.eclipse.jgit.util.io.ThrowingPrintWriter;
 import org.kohsuke.args4j.CmdLineException;
 import org.kohsuke.args4j.Option;
@@ -89,6 +93,9 @@ public abstract class TextBuiltin {
 	@Option(name = "--help", usage = "usage_displayThisHelpText", aliases = { "-h" })
 	private boolean help;
 
+	@Option(name = "--ssh", usage = "usage_sshDriver")
+	private SshDriver sshDriver = SshDriver.JSCH;
+
 	/**
 	 * Input stream, typically this is standard input.
 	 *
@@ -239,6 +246,20 @@ public abstract class TextBuiltin {
 	 */
 	public final void execute(String[] args) throws Exception {
 		parseArguments(args);
+		switch (sshDriver) {
+		case APACHE: {
+			SshdSessionFactory factory = new SshdSessionFactory(
+					new JGitKeyCache());
+			Runtime.getRuntime()
+					.addShutdownHook(new Thread(() -> factory.close()));
+			SshSessionFactory.setInstance(factory);
+			break;
+		}
+		case JSCH:
+		default:
+			SshSessionFactory.setInstance(null);
+			break;
+		}
 		run();
 	}
 

org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/internal/SshDriver.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2018, Thomas Wolf <thomas.wolf@paranor.ch>
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.eclipse.jgit.pgm.internal;
+
+/**
+ * Simple enumeration for the available built-in ssh clients.
+ */
+public enum SshDriver {
+
+	/** Default client: use JSch. */
+	JSCH,
+
+	/** Use the Apache MINA sshd client from org.eclipse.jgit.ssh.apache. */
+	APACHE;
+
+}