Poor man's fallback to ssh-agent

- because we are not emulating a TTY we cannot handle passphrase projected keys

Author: stephenc

src/main/java/com/cloudbees/jenkins/plugins/sshagent/unix/UnixRemoteAgent.java

@@ -0,0 +1,89 @@
+package com.cloudbees.jenkins.plugins.sshagent.unix;
+
+import com.cloudbees.jenkins.plugins.sshagent.RemoteAgent;
+import hudson.Launcher;
+import hudson.model.TaskListener;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.util.concurrent.TimeUnit;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * Use the ssh-agent command.
+ *
+ * @todo support passphrase
+ */
+public class UnixRemoteAgent implements RemoteAgent {
+    /**
+     * The socket bound by the agent.
+     */
+    private final String socket;
+
+    /**
+     * The pid of the ssh-agent process
+     */
+    private final int pid;
+
+    /**
+     * Our launcher;
+     */
+    private final Launcher launcher;
+
+    /**
+     * Our listener.
+     */
+    private final TaskListener listener;
+
+    public UnixRemoteAgent(Launcher launcher, TaskListener listener) throws IOException, InterruptedException {
+        this.launcher = launcher;
+        this.listener = listener;
+        ByteArrayOutputStream out = new ByteArrayOutputStream();
+        this.launcher.launch()
+                .cmds("/usr/bin/ssh-agent")
+                .stderr(listener.getLogger())
+                .stdout(out)
+                .start()
+                .joinWithTimeout(5, TimeUnit.SECONDS, listener);
+        String output = out.toString("UTF-8");
+        listener.getLogger().println(output);
+        Matcher pidMatcher = Pattern.compile("SSH_AGENT_PID=(\\d+)[; ]").matcher(output);
+        Matcher sockMatcher = Pattern.compile("SSH_AUTH_SOCK=([^ ]+)[; ]").matcher(output);
+        if (pidMatcher.find() && sockMatcher.find()) {
+            pid = Integer.parseInt(pidMatcher.group(1));
+            socket = sockMatcher.group(1);
+        } else {
+            listener.getLogger().println("Could not determine PID");
+            throw new IOException("Could not start ssh-agent");
+        }
+    }
+
+    public String getSocket() {
+        return socket;
+    }
+
+    public void addIdentity(String privateKey, String passphrase, String comment) throws IOException {
+        this.launcher.launch().cmds("ssh-add", "-")
+                .envs("SSH_AUTH_SOCK=" + socket, "SSH_AGENT_PID=" + Integer.toString(pid))
+                .stdin(new ByteArrayInputStream(privateKey.getBytes("UTF-8")))
+                .stdout(listener)
+                .stderr(listener.getLogger())
+                .start();
+    }
+
+    public void stop() {
+        try {
+            launcher.launch()
+                    .cmds("ssh-agent", "-k")
+                    .envs("SSH_AUTH_SOCK=" + socket, "SSH_AGENT_PID=" + Integer.toString(pid))
+                    .start()
+                    .joinWithTimeout(10, TimeUnit.SECONDS, listener);
+        } catch (IOException e) {
+            e.printStackTrace(listener.getLogger());
+        } catch (InterruptedException e) {
+            e.printStackTrace(listener.getLogger());
+        }
+    }
+}

src/main/java/com/cloudbees/jenkins/plugins/sshagent/unix/UnixRemoteAgentFactory.java

@@ -0,0 +1,64 @@
+/*
+ * The MIT License
+ *
+ * Copyright (c) 2012, CloudBees, Inc., Stephen Connolly.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.cloudbees.jenkins.plugins.sshagent.unix;
+
+import com.cloudbees.jenkins.plugins.sshagent.RemoteAgent;
+import com.cloudbees.jenkins.plugins.sshagent.RemoteAgentFactory;
+import hudson.Extension;
+import hudson.Launcher;
+import hudson.model.TaskListener;
+
+/**
+ * Fall back to the raw unix command... but favour this the least as cannot support passphrases without TTY emulation.
+ */
+@Extension(ordinal = Double.MIN_VALUE)
+public class UnixRemoteAgentFactory extends RemoteAgentFactory {
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public String getDisplayName() {
+        return "Unix ssh-agent command";
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean isSupported(Launcher launcher, final TaskListener listener) {
+        return launcher.isUnix();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public RemoteAgent start(Launcher launcher, final TaskListener listener) throws Throwable {
+        return launcher.getChannel().call(new UnixRemoteAgentStarter(launcher, listener));
+    }
+
+}
+

src/main/java/com/cloudbees/jenkins/plugins/sshagent/unix/UnixRemoteAgentStarter.java

@@ -0,0 +1,64 @@
+/*
+ * The MIT License
+ *
+ * Copyright (c) 2012, CloudBees, Inc., Stephen Connolly.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.cloudbees.jenkins.plugins.sshagent.unix;
+
+import com.cloudbees.jenkins.plugins.sshagent.RemoteAgent;
+import hudson.Launcher;
+import hudson.model.TaskListener;
+import hudson.remoting.Callable;
+import hudson.remoting.Channel;
+
+/**
+ * @author stephenc
+ * @since 26/10/2012 15:45
+ */
+public class UnixRemoteAgentStarter implements Callable<RemoteAgent, Throwable> {
+    /**
+     * Need to pass this through.
+     */
+    private final TaskListener listener;
+    private final Launcher launcher;
+
+    /**
+     * Constructor.
+     *
+     * @param launcher the launcher to pass to the agent
+     * @param listener the listener to pass to the agent.
+     */
+    public UnixRemoteAgentStarter(Launcher launcher, TaskListener listener) {
+        this.listener = listener;
+        this.launcher = launcher;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public RemoteAgent call() throws Throwable {
+        final UnixRemoteAgent instance = new UnixRemoteAgent(launcher, listener);
+        final Channel channel = Channel.current();
+        return channel == null ? instance : channel.export(RemoteAgent.class, instance);
+    }
+}
+