chore: use new guarantees

packages/noports_core/lib/src/common/file_system_utils.dart

@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'dart:io';
 import 'package:at_utils/at_utils.dart';
 import 'package:path/path.dart' as path;
@@ -60,15 +61,28 @@ String getDefaultSshnpConfigDirectory(String homeDirectory) {
   return path.normalize('$homeDirectory/.sshnp/config');
 }
 
-Future<(String, String)> generateSshKeys(
-    {required bool rsa,
-    required String sessionId,
-    String? sshHomeDirectory}) async {
+(String, String, String) _getEphemeralKeysPath(
+    String? sshHomeDirectory, String sessionId) {
   sshHomeDirectory ??= getDefaultSshDirectory(getHomeDirectory()!);
   if (!Directory(sshHomeDirectory).existsSync()) {
     Directory(sshHomeDirectory).createSync();
   }
 
+  return (
+    sshHomeDirectory,
+    '$sshHomeDirectory/${sessionId}_sshnp.pub',
+    '$sshHomeDirectory/${sessionId}_sshnp'
+  );
+}
+
+Future<(String, String)> generateEphemeralSshKeys(
+    {required bool rsa,
+    required String sessionId,
+    String? sshHomeDirectory}) async {
+  var (normalizedSshHomeDirectory, sshPublicKeyPath, sshPrivateKeyPath) =
+      _getEphemeralKeysPath(sshHomeDirectory, sessionId);
+  sshHomeDirectory = normalizedSshHomeDirectory;
+
   if (rsa) {
     await Process.run('ssh-keygen',
         ['-t', 'rsa', '-b', '4096', '-f', '${sessionId}_sshnp', '-q', '-N', ''],
@@ -90,12 +104,24 @@ Future<(String, String)> generateSshKeys(
         workingDirectory: sshHomeDirectory);
   }
 
-  String sshPublicKey =
-      await File('$sshHomeDirectory/${sessionId}_sshnp.pub').readAsString();
-  String sshPrivateKey =
-      await File('$sshHomeDirectory/${sessionId}_sshnp').readAsString();
+  var keys = await Future.wait([
+    File(sshPublicKeyPath).readAsString(),
+    File(sshPrivateKeyPath).readAsString()
+  ]);
+
+  return (keys[0], keys[1]);
+}
 
-  return (sshPublicKey, sshPrivateKey);
+Future<void> cleanUpEphemeralSshKeys({
+  required String sessionId,
+  String? sshHomeDirectory,
+}) async {
+  var (_, sshPublicKeyPath, sshPrivateKeyPath) =
+      _getEphemeralKeysPath(sshHomeDirectory, sessionId);
+  await Future.wait([
+    File(sshPublicKeyPath).delete(),
+    File(sshPrivateKeyPath).delete(),
+  ]);
 }
 
 Future<void> addEphemeralKeyToAuthorizedKeys(

packages/noports_core/lib/src/sshnp/sshnp_impl/sshnp_forward_exec_impl.dart

@@ -12,6 +12,7 @@ import 'package:path/path.dart' as path;
 
 class SSHNPForwardExecImpl extends SSHNPImpl
     with SSHNPForwardDirection, SSHNPLocalFileMixin {
+  late String ephemeralPrivateKeyPath;
   SSHNPForwardExecImpl({
     required AtClient atClient,
     required SSHNPParams params,
@@ -45,21 +46,17 @@ class SSHNPForwardExecImpl extends SSHNPImpl
       String? errorMessage;
       Process? process;
 
-      // If using exec then we can assume we're on something unix-y
-      // So we can write the ephemeralPrivateKey to a tmp file,
-      // set its permissions appropriately, and remove it after we've
-      // executed the command
-      var tmpFileName =
-          path.normalize('$sshHomeDirectory/tmp/ephemeral_$sessionId');
-      File tmpFile = File(tmpFileName);
+      var ephemeralPrivateKeyPath = path.normalize(
+          '$sshnpHomeDirectory/sessions/$sessionId/ephemeral_private_key');
+      File tmpFile = File(ephemeralPrivateKeyPath);
       await tmpFile.create(recursive: true);
       await tmpFile.writeAsString(ephemeralPrivateKey,
           mode: FileMode.write, flush: true);
-      await Process.run('chmod', ['go-rwx', tmpFileName]);
+      await Process.run('chmod', ['go-rwx', ephemeralPrivateKeyPath]);
 
       String argsString = '$remoteUsername@$host'
           ' -p $sshrvdPort'
-          ' -i $tmpFileName'
+          ' -i $ephemeralPrivateKeyPath'
           ' -L $localPort:localhost:${params.remoteSshdPort}'
           ' -o LogLevel=VERBOSE'
           ' -t -t'
@@ -138,4 +135,10 @@ class SSHNPForwardExecImpl extends SSHNPImpl
       );
     }
   }
+
+  @override
+  Future<void> cleanUp() async {
+    await deleteFile(ephemeralPrivateKeyPath);
+    super.cleanUp();
+  }
 }

packages/noports_core/lib/src/sshnp/sshnp_impl/sshnp_impl.dart

@@ -151,6 +151,12 @@ abstract class SSHNPImpl implements SSHNP {
       _initializeStarted = true;
     }
 
+    // Schedule a cleanup on exit
+    unawaited(doneCompleter.future.then((_) async {
+      logger.info('SSHNPImpl done');
+      await cleanUp();
+    }));
+
     try {
       if (!(await atSignIsActivated(atClient, sshnpdAtSign))) {
         logger.severe('Device address $sshnpdAtSign is not activated.');
@@ -297,7 +303,6 @@ abstract class SSHNPImpl implements SSHNP {
     try {
       return (await atClient.get(userNameRecordID)).value as String;
     } catch (e, s) {
-      await cleanUp();
       throw SSHNPError(
         "Device unknown, or username not shared\n"
         "hint: make sure the device shares username or set remote username manually",
@@ -344,7 +349,6 @@ abstract class SSHNPImpl implements SSHNP {
       counter++;
       if (counter == 100) {
         logger.warning('Timed out waiting for sshrvd response');
-        await cleanUp();
         throw ('Connection timeout to sshrvd $host service\nhint: make sure host is valid and online');
       }
     }
@@ -379,7 +383,6 @@ abstract class SSHNPImpl implements SSHNP {
           ..ttl = 10000);
       await notify(sendOurPublicKeyToSshnpd, toSshPublicKey);
     } catch (e, s) {
-      await cleanUp();
       throw SSHNPError(
         'Error opening or validating public key file or sending to remote atSign',
         error: e,

packages/noports_core/lib/src/sshnp/sshnp_impl/sshnp_legacy_impl.dart

@@ -70,7 +70,6 @@ class SSHNPLegacyImpl extends SSHNPImpl
     );
 
     bool acked = await waitForDaemonResponse();
-    await cleanUp();
     if (!acked) {
       var error = SSHNPError(
         'sshnp timed out: waiting for daemon response\nhint: make sure the device is online',

packages/noports_core/lib/src/sshnp/sshnp_impl/sshnp_local_file_mixin.dart

@@ -1,10 +1,14 @@
 import 'dart:io';
 
+import 'package:meta/meta.dart';
+import 'package:noports_core/src/common/file_system_utils.dart';
 import 'package:noports_core/src/sshnp/sshnp_impl/sshnp_impl.dart';
 import 'package:noports_core/src/sshnp/sshnp_result.dart';
 
 mixin SSHNPLocalFileMixin on SSHNPImpl {
+  late final String homeDirectory;
   late final String sshHomeDirectory;
+  late final String sshnpHomeDirectory;
 
   final bool _isValidPlatform =
       Platform.isLinux || Platform.isMacOS || Platform.isWindows;
@@ -19,8 +23,28 @@ mixin SSHNPLocalFileMixin on SSHNPImpl {
       throw SSHNPError(
           'The current platform is not supported: ${Platform.operatingSystem}');
     }
+    try {
+      homeDirectory = getHomeDirectory(throwIfNull: true)!;
+    } catch (e, s) {
+      throw SSHNPError('Unable to determine the home directory',
+          error: e, stackTrace: s);
+    }
+    sshHomeDirectory = getDefaultSshDirectory(homeDirectory);
+    sshnpHomeDirectory = getDefaultSshnpDirectory(homeDirectory);
+
     await super.init();
-
     if (initializedCompleter.isCompleted) return;
   }
+
+  @protected
+  Future<bool> deleteFile(String fileName) async {
+    try {
+      final file = File(fileName);
+      await file.delete();
+      return true;
+    } catch (e) {
+      logger.severe("Error deleting file : $fileName");
+      return false;
+    }
+  }
 }

packages/noports_core/lib/src/sshnp/sshnp_impl/sshnp_reverse_impl.dart

@@ -66,7 +66,6 @@ class SSHNPReverseImpl extends SSHNPImpl
         sessionId: sessionId);
 
     bool acked = await waitForDaemonResponse();
-    await cleanUp();
     if (!acked) {
       var error =
           SSHNPError('sshnp connection timeout: waiting for daemon response');

packages/noports_core/lib/src/sshnp/sshnp_impl/sshnp_reverse_mixin.dart

@@ -1,5 +1,4 @@
 import 'dart:async';
-import 'dart:io';
 
 import 'package:noports_core/src/common/file_system_utils.dart';
 import 'package:noports_core/src/sshnp/sshnp_impl/sshnp_local_file_mixin.dart';
@@ -10,13 +9,13 @@ import 'package:noports_core/utils.dart';
 /// e.g. class [SSHNPReverseImpl] extends [SSHNPImpl] with [SSHNPLocalFileMixin], [SSHNPReverseMixin]
 /// Note that the order of mixins is important here.
 mixin SSHNPReverseMixin on SSHNPLocalFileMixin {
-  /// Set by [generateSshKeys] during [init], if we're not doing direct ssh.
+  /// Set by [generateEphemeralSshKeys] during [init], if we're not doing direct ssh.
   /// sshnp generates a new keypair for each ssh session, using ed25519 by
   /// default but rsa if the [rsa] flag is set to true. sshnp will write
   /// [sshPublicKey] to ~/.ssh/authorized_keys
   late final String sshPublicKey;
 
-  /// Set by [generateSshKeys] during [init].
+  /// Set by [generateEphemeralSshKeys] during [init].
   /// sshnp generates a new keypair for each ssh session, using ed25519 by
   /// default but rsa if the [rsa] flag is set to true. sshnp will send the
   /// [sshPrivateKey] to sshnpd
@@ -35,7 +34,7 @@ mixin SSHNPReverseMixin on SSHNPLocalFileMixin {
     logger.info('Generating ephemeral keypair');
     try {
       var (String ephemeralPublicKey, String ephemeralPrivateKey) =
-          await generateSshKeys(
+          await generateEphemeralSshKeys(
         rsa: params.rsa,
         sessionId: sessionId,
         sshHomeDirectory: sshHomeDirectory,
@@ -72,23 +71,12 @@ mixin SSHNPReverseMixin on SSHNPLocalFileMixin {
     var sshHomeDirectory = getDefaultSshDirectory(homeDirectory);
     logger.info('Tidying up files');
 // Delete the generated RSA keys and remove the entry from ~/.ssh/authorized_keys
-    await _deleteFile('$sshHomeDirectory/${sessionId}_sshnp');
-    await _deleteFile('$sshHomeDirectory/${sessionId}_sshnp.pub');
+    await cleanUpEphemeralSshKeys(
+        sessionId: sessionId, sshHomeDirectory: sshHomeDirectory);
     await removeEphemeralKeyFromAuthorizedKeys(sessionId, logger,
         sshHomeDirectory: sshHomeDirectory);
     super.cleanUp();
   }
 
-  Future<bool> _deleteFile(String fileName) async {
-    try {
-      final file = File(fileName);
-      await file.delete();
-      return true;
-    } catch (e) {
-      logger.severe("Error deleting file : $fileName");
-      return false;
-    }
-  }
-
   bool get usingSshrv => sshrvdPort != null;
 }

packages/noports_core/lib/src/sshnpd/sshnpd_impl.dart

@@ -509,7 +509,7 @@ class SSHNPDImpl implements SSHNPD {
       ///   `authorized_keys` file, limiting permissions (e.g. hosts and ports
       ///   which can be forwarded to) as per the `--ephemeral-permissions` option
       var (String ephemeralPublicKey, String ephemeralPrivateKey) =
-          await generateSshKeys(rsa: rsa, sessionId: sessionId);
+          await generateEphemeralSshKeys(rsa: rsa, sessionId: sessionId);
 
       await addEphemeralKeyToAuthorizedKeys(
           sshPublicKey: ephemeralPublicKey,

packages/sshnoports/bin/sshnp.dart

@@ -33,11 +33,6 @@ void main(List<String> args) async {
     exit(0);
   }
 
-  ProcessSignal.sigint.watch().listen((signal) async {
-    await sshnp?.cleanUp();
-    exit(1);
-  });
-
   await runZonedGuarded(() async {
     try {
       params = SSHNPParams.fromPartial(SSHNPPartialParams.fromArgList(args));
@@ -98,8 +93,6 @@ void main(List<String> args) async {
       if (verbose) {
         stderr.writeln('\nStack Trace: ${stackTrace.toString()}');
       }
-
-      await sshnp?.cleanUp();
       exit(1);
     }
   }, (Object error, StackTrace stackTrace) async {
@@ -109,8 +102,6 @@ void main(List<String> args) async {
     if (verbose) {
       stderr.writeln('\nStack Trace: ${stackTrace.toString()}');
     }
-
-    await sshnp?.cleanUp();
     exit(1);
   });
 }