feat: known_hosts (#206)

src/main/kotlin/app/termora/OptionPane.kt

@@ -6,8 +6,6 @@ import com.formdev.flatlaf.util.SystemInfo
 import com.jetbrains.JBR
 import kotlinx.coroutines.*
 import kotlinx.coroutines.swing.Swing
-import org.apache.commons.lang3.StringUtils
-import org.jdesktop.swingx.JXLabel
 import java.awt.BorderLayout
 import java.awt.Component
 import java.awt.Desktop
@@ -57,6 +55,7 @@ object OptionPane {
                 pane.selectInitialValue()
             }
         })
+        dialog.setLocationRelativeTo(parentComponent)
         dialog.isVisible = true
         dialog.dispose()
         val selectedValue = pane.value

src/main/kotlin/app/termora/SSHTerminalTab.kt

@@ -29,7 +29,7 @@ import org.apache.sshd.common.session.SessionListener.Event
 import org.apache.sshd.common.util.net.SshdSocketAddress
 import org.slf4j.LoggerFactory
 import java.nio.charset.StandardCharsets
-import java.util.EventObject
+import java.util.*
 import javax.swing.JComponent
 import javax.swing.SwingUtilities
 
@@ -87,9 +87,11 @@ class SSHTerminalTab(windowScope: WindowScope, host: Host) :
             terminal.write("SSH client is opening...\r\n")
         }
 
+        val owner = SwingUtilities.getWindowAncestor(terminalPanel)
         val client = SshClients.openClient(host).also { sshClient = it }
+        client.serverKeyVerifier = DialogServerKeyVerifier(owner)
         // keyboard interactive
-        client.userInteraction = TerminalUserInteraction(SwingUtilities.getWindowAncestor(terminalPanel))
+        client.userInteraction = TerminalUserInteraction(owner)
 
         val sessionListener = MySessionListener()
         val channelListener = MyChannelListener()

src/main/kotlin/app/termora/SshClients.kt

@@ -2,14 +2,20 @@ package app.termora
 
 import app.termora.keymgr.OhKeyPairKeyPairProvider
 import app.termora.terminal.TerminalSize
+import org.apache.commons.lang3.StringUtils
 import org.apache.sshd.client.ClientBuilder
 import org.apache.sshd.client.SshClient
 import org.apache.sshd.client.channel.ChannelShell
 import org.apache.sshd.client.config.hosts.HostConfigEntryResolver
+import org.apache.sshd.client.config.hosts.KnownHostEntry
 import org.apache.sshd.client.kex.DHGClient
+import org.apache.sshd.client.keyverifier.KnownHostsServerKeyVerifier
+import org.apache.sshd.client.keyverifier.ModifiedServerKeyAcceptor
+import org.apache.sshd.client.keyverifier.ServerKeyVerifier
 import org.apache.sshd.client.session.ClientSession
 import org.apache.sshd.common.SshException
 import org.apache.sshd.common.channel.PtyChannelConfiguration
+import org.apache.sshd.common.config.keys.KeyUtils
 import org.apache.sshd.common.global.KeepAliveHandler
 import org.apache.sshd.common.kex.BuiltinDHFactories
 import org.apache.sshd.common.keyprovider.KeyIdentityProvider
@@ -22,9 +28,16 @@ import org.eclipse.jgit.transport.CredentialsProvider
 import org.eclipse.jgit.transport.sshd.IdentityPasswordProvider
 import org.eclipse.jgit.transport.sshd.ProxyData
 import org.slf4j.LoggerFactory
+import java.awt.Window
 import java.net.InetSocketAddress
 import java.net.Proxy
+import java.net.SocketAddress
+import java.nio.file.Paths
+import java.security.PublicKey
 import java.time.Duration
+import java.util.concurrent.atomic.AtomicBoolean
+import javax.swing.JOptionPane
+import javax.swing.SwingUtilities
 import kotlin.math.max
 
 object SshClients {
@@ -191,4 +204,74 @@ object SshClients {
         sshClient.start()
         return sshClient
     }
-}
+}
+
+
+private class MyDialogServerKeyVerifier(private val owner: Window) : ServerKeyVerifier, ModifiedServerKeyAcceptor {
+    override fun verifyServerKey(
+        clientSession: ClientSession,
+        remoteAddress: SocketAddress,
+        serverKey: PublicKey
+    ): Boolean {
+        val result = AtomicBoolean(false)
+
+        SwingUtilities.invokeAndWait {
+            result.set(
+                OptionPane.showConfirmDialog(
+                    parentComponent = owner,
+                    message = I18n.getString(
+                        "termora.host.verify-server-key",
+                        remoteAddress.toString().replace("/", StringUtils.EMPTY),
+                        KeyUtils.getKeyType(serverKey),
+                        KeyUtils.getFingerPrint(serverKey)
+                    ),
+                    optionType = JOptionPane.OK_CANCEL_OPTION,
+                    messageType = JOptionPane.WARNING_MESSAGE,
+                ) == JOptionPane.OK_OPTION
+            )
+        }
+
+        return result.get()
+    }
+
+    override fun acceptModifiedServerKey(
+        clientSession: ClientSession?,
+        remoteAddress: SocketAddress?,
+        entry: KnownHostEntry?,
+        expected: PublicKey?,
+        actual: PublicKey?
+    ): Boolean {
+        val result = AtomicBoolean(false)
+
+        SwingUtilities.invokeAndWait {
+            result.set(
+                OptionPane.showConfirmDialog(
+                    parentComponent = owner,
+                    message = I18n.getString(
+                        "termora.host.modified-server-key",
+                        remoteAddress.toString().replace("/", StringUtils.EMPTY),
+                        KeyUtils.getKeyType(expected),
+                        KeyUtils.getFingerPrint(expected),
+                        KeyUtils.getKeyType(actual),
+                        KeyUtils.getFingerPrint(actual),
+                    ),
+                    optionType = JOptionPane.OK_CANCEL_OPTION,
+                    messageType = JOptionPane.WARNING_MESSAGE,
+                ) == JOptionPane.OK_OPTION
+            )
+        }
+
+        return result.get()
+    }
+}
+
+class DialogServerKeyVerifier(
+    owner: Window,
+) : KnownHostsServerKeyVerifier(
+    MyDialogServerKeyVerifier(owner),
+    Paths.get(Application.getBaseDataDir().absolutePath, "known_hosts")
+) {
+    init {
+        modifiedServerKeyAcceptor = delegateVerifier as ModifiedServerKeyAcceptor
+    }
+}

src/main/kotlin/app/termora/transport/SftpFileSystemPanel.kt

@@ -115,8 +115,9 @@ class SftpFileSystemPanel(
         try {
             val client = SshClients.openClient(host).apply { client = this }
             withContext(Dispatchers.Swing) {
-                client.userInteraction =
-                    TerminalUserInteraction(SwingUtilities.getWindowAncestor(this@SftpFileSystemPanel))
+                val owner = SwingUtilities.getWindowAncestor(this@SftpFileSystemPanel)
+                client.userInteraction = TerminalUserInteraction(owner)
+                client.serverKeyVerifier = DialogServerKeyVerifier(owner)
             }
             val session = SshClients.openSession(host, client).apply { session = this }
             fileSystem = SftpClientFactory.instance().createSftpFileSystem(session)