Ausgabe der neuen DB Einträge

venv/lib/python3.9/site-packages/twisted/conch/test/test_filetransfer.py

@@ -0,0 +1,881 @@
+# -*- test-case-name: twisted.conch.test.test_filetransfer -*-
+# Copyright (c) Twisted Matrix Laboratories.
+# See LICENSE file for details.
+
+"""
+Tests for L{twisted.conch.ssh.filetransfer}.
+"""
+
+from __future__ import division, absolute_import
+
+import os
+import re
+import struct
+
+from twisted.python.reflect import requireModule
+from twisted.trial import unittest
+
+cryptography = requireModule("cryptography")
+unix = requireModule("twisted.conch.unix")
+
+if cryptography:
+    from twisted.conch import avatar
+    from twisted.conch.ssh import common, connection, filetransfer, session
+else:
+    class avatar:
+        class ConchUser: pass
+
+from twisted.internet import defer
+from twisted.protocols import loopback
+from twisted.python import components
+from twisted.python.compat import long, _PY37PLUS
+from twisted.python.filepath import FilePath
+
+
+class TestAvatar(avatar.ConchUser):
+    def __init__(self):
+        avatar.ConchUser.__init__(self)
+        self.channelLookup[b'session'] = session.SSHSession
+        self.subsystemLookup[b'sftp'] = filetransfer.FileTransferServer
+
+    def _runAsUser(self, f, *args, **kw):
+        try:
+            f = iter(f)
+        except TypeError:
+            f = [(f, args, kw)]
+        for i in f:
+            func = i[0]
+            args = len(i)>1 and i[1] or ()
+            kw = len(i)>2 and i[2] or {}
+            r = func(*args, **kw)
+        return r
+
+
+class FileTransferTestAvatar(TestAvatar):
+
+    def __init__(self, homeDir):
+        TestAvatar.__init__(self)
+        self.homeDir = homeDir
+
+    def getHomeDir(self):
+        return FilePath(os.getcwd()).preauthChild(self.homeDir.path)
+
+
+class ConchSessionForTestAvatar:
+
+    def __init__(self, avatar):
+        self.avatar = avatar
+
+if unix:
+    if not hasattr(unix, 'SFTPServerForUnixConchUser'):
+        # unix should either be a fully working module, or None.  I'm not sure
+        # how this happens, but on win32 it does.  Try to cope.  --spiv.
+        import warnings
+        warnings.warn(("twisted.conch.unix imported %r, "
+                       "but doesn't define SFTPServerForUnixConchUser'")
+                      % (unix,))
+        unix = None
+    else:
+        class FileTransferForTestAvatar(unix.SFTPServerForUnixConchUser):
+
+            def gotVersion(self, version, otherExt):
+                return {b'conchTest' : b'ext data'}
+
+            def extendedRequest(self, extName, extData):
+                if extName == b'testExtendedRequest':
+                    return b'bar'
+                raise NotImplementedError
+
+        components.registerAdapter(FileTransferForTestAvatar,
+                                   TestAvatar,
+                                   filetransfer.ISFTPServer)
+
+class SFTPTestBase(unittest.TestCase):
+
+    def setUp(self):
+        self.testDir = FilePath(self.mktemp())
+        # Give the testDir another level so we can safely "cd .." from it in
+        # tests.
+        self.testDir = self.testDir.child('extra')
+        self.testDir.child('testDirectory').makedirs(True)
+
+        with self.testDir.child('testfile1').open(mode='wb') as f:
+            f.write(b'a'*10+b'b'*10)
+            with open('/dev/urandom', 'rb') as f2:
+                f.write(f2.read(1024*64)) # random data
+        self.testDir.child('testfile1').chmod(0o644)
+        with self.testDir.child('testRemoveFile').open(mode='wb') as f:
+            f.write(b'a')
+        with self.testDir.child('testRenameFile').open(mode='wb') as f:
+            f.write(b'a')
+        with self.testDir.child('.testHiddenFile').open(mode='wb') as f:
+            f.write(b'a')
+
+
+class OurServerOurClientTests(SFTPTestBase):
+
+    if not unix:
+        skip = "can't run on non-posix computers"
+
+    def setUp(self):
+        SFTPTestBase.setUp(self)
+
+        self.avatar = FileTransferTestAvatar(self.testDir)
+        self.server = filetransfer.FileTransferServer(avatar=self.avatar)
+        clientTransport = loopback.LoopbackRelay(self.server)
+
+        self.client = filetransfer.FileTransferClient()
+        self._serverVersion = None
+        self._extData = None
+        def _(serverVersion, extData):
+            self._serverVersion = serverVersion
+            self._extData = extData
+        self.client.gotServerVersion = _
+        serverTransport = loopback.LoopbackRelay(self.client)
+        self.client.makeConnection(clientTransport)
+        self.server.makeConnection(serverTransport)
+
+        self.clientTransport = clientTransport
+        self.serverTransport = serverTransport
+
+        self._emptyBuffers()
+
+
+    def _emptyBuffers(self):
+        while self.serverTransport.buffer or self.clientTransport.buffer:
+            self.serverTransport.clearBuffer()
+            self.clientTransport.clearBuffer()
+
+
+    def tearDown(self):
+        self.serverTransport.loseConnection()
+        self.clientTransport.loseConnection()
+        self.serverTransport.clearBuffer()
+        self.clientTransport.clearBuffer()
+
+
+    def test_serverVersion(self):
+        self.assertEqual(self._serverVersion, 3)
+        self.assertEqual(self._extData, {b'conchTest': b'ext data'})
+
+
+    def test_interface_implementation(self):
+        """
+        It implements the ISFTPServer interface.
+        """
+        self.assertTrue(
+            filetransfer.ISFTPServer.providedBy(self.server.client),
+            "ISFTPServer not provided by %r" % (self.server.client,))
+
+
+    def test_openedFileClosedWithConnection(self):
+        """
+        A file opened with C{openFile} is close when the connection is lost.
+        """
+        d = self.client.openFile(b"testfile1", filetransfer.FXF_READ |
+                                 filetransfer.FXF_WRITE, {})
+        self._emptyBuffers()
+
+        oldClose = os.close
+        closed = []
+        def close(fd):
+            closed.append(fd)
+            oldClose(fd)
+
+        self.patch(os, "close", close)
+
+        def _fileOpened(openFile):
+            fd = self.server.openFiles[openFile.handle[4:]].fd
+            self.serverTransport.loseConnection()
+            self.clientTransport.loseConnection()
+            self.serverTransport.clearBuffer()
+            self.clientTransport.clearBuffer()
+            self.assertEqual(self.server.openFiles, {})
+            self.assertIn(fd, closed)
+
+        d.addCallback(_fileOpened)
+        return d
+
+
+    def test_openedDirectoryClosedWithConnection(self):
+        """
+        A directory opened with C{openDirectory} is close when the connection
+        is lost.
+        """
+        d = self.client.openDirectory('')
+        self._emptyBuffers()
+
+        def _getFiles(openDir):
+            self.serverTransport.loseConnection()
+            self.clientTransport.loseConnection()
+            self.serverTransport.clearBuffer()
+            self.clientTransport.clearBuffer()
+            self.assertEqual(self.server.openDirs, {})
+
+        d.addCallback(_getFiles)
+        return d
+
+
+    def test_openFileIO(self):
+        d = self.client.openFile(b"testfile1", filetransfer.FXF_READ |
+                                 filetransfer.FXF_WRITE, {})
+        self._emptyBuffers()
+
+        def _fileOpened(openFile):
+            self.assertEqual(openFile, filetransfer.ISFTPFile(openFile))
+            d = _readChunk(openFile)
+            d.addCallback(_writeChunk, openFile)
+            return d
+
+        def _readChunk(openFile):
+            d = openFile.readChunk(0, 20)
+            self._emptyBuffers()
+            d.addCallback(self.assertEqual, b'a'*10 + b'b'*10)
+            return d
+
+        def _writeChunk(_, openFile):
+            d = openFile.writeChunk(20, b'c'*10)
+            self._emptyBuffers()
+            d.addCallback(_readChunk2, openFile)
+            return d
+
+        def _readChunk2(_, openFile):
+            d = openFile.readChunk(0, 30)
+            self._emptyBuffers()
+            d.addCallback(self.assertEqual, b'a'*10 + b'b'*10 + b'c'*10)
+            return d
+
+        d.addCallback(_fileOpened)
+        return d
+
+
+    def test_closedFileGetAttrs(self):
+        d = self.client.openFile(b"testfile1", filetransfer.FXF_READ |
+                                 filetransfer.FXF_WRITE, {})
+        self._emptyBuffers()
+
+        def _getAttrs(_, openFile):
+            d = openFile.getAttrs()
+            self._emptyBuffers()
+            return d
+
+        def _err(f):
+            self.flushLoggedErrors()
+            return f
+
+        def _close(openFile):
+            d = openFile.close()
+            self._emptyBuffers()
+            d.addCallback(_getAttrs, openFile)
+            d.addErrback(_err)
+            return self.assertFailure(d, filetransfer.SFTPError)
+
+        d.addCallback(_close)
+        return d
+
+
+    def test_openFileAttributes(self):
+        d = self.client.openFile(b"testfile1", filetransfer.FXF_READ |
+                                 filetransfer.FXF_WRITE, {})
+        self._emptyBuffers()
+
+        def _getAttrs(openFile):
+            d = openFile.getAttrs()
+            self._emptyBuffers()
+            d.addCallback(_getAttrs2)
+            return d
+
+        def _getAttrs2(attrs1):
+            d = self.client.getAttrs(b'testfile1')
+            self._emptyBuffers()
+            d.addCallback(self.assertEqual, attrs1)
+            return d
+
+        return d.addCallback(_getAttrs)
+
+
+    def test_openFileSetAttrs(self):
+        # XXX test setAttrs
+        # Ok, how about this for a start?  It caught a bug :)  -- spiv.
+        d = self.client.openFile(b"testfile1", filetransfer.FXF_READ |
+                                 filetransfer.FXF_WRITE, {})
+        self._emptyBuffers()
+
+        def _getAttrs(openFile):
+            d = openFile.getAttrs()
+            self._emptyBuffers()
+            d.addCallback(_setAttrs)
+            return d
+
+        def _setAttrs(attrs):
+            attrs['atime'] = 0
+            d = self.client.setAttrs(b'testfile1', attrs)
+            self._emptyBuffers()
+            d.addCallback(_getAttrs2)
+            d.addCallback(self.assertEqual, attrs)
+            return d
+
+        def _getAttrs2(_):
+            d = self.client.getAttrs(b'testfile1')
+            self._emptyBuffers()
+            return d
+
+        d.addCallback(_getAttrs)
+        return d
+
+
+    def test_openFileExtendedAttributes(self):
+        """
+        Check that L{filetransfer.FileTransferClient.openFile} can send
+        extended attributes, that should be extracted server side. By default,
+        they are ignored, so we just verify they are correctly parsed.
+        """
+        savedAttributes = {}
+        oldOpenFile = self.server.client.openFile
+        def openFile(filename, flags, attrs):
+            savedAttributes.update(attrs)
+            return oldOpenFile(filename, flags, attrs)
+        self.server.client.openFile = openFile
+
+        d = self.client.openFile(b"testfile1", filetransfer.FXF_READ |
+                filetransfer.FXF_WRITE, {"ext_foo": b"bar"})
+        self._emptyBuffers()
+
+        def check(ign):
+            self.assertEqual(savedAttributes, {"ext_foo": b"bar"})
+
+        return d.addCallback(check)
+
+
+    def test_removeFile(self):
+        d = self.client.getAttrs(b"testRemoveFile")
+        self._emptyBuffers()
+
+        def _removeFile(ignored):
+            d = self.client.removeFile(b"testRemoveFile")
+            self._emptyBuffers()
+            return d
+
+        d.addCallback(_removeFile)
+        d.addCallback(_removeFile)
+        return self.assertFailure(d, filetransfer.SFTPError)
+
+
+    def test_renameFile(self):
+        d = self.client.getAttrs(b"testRenameFile")
+        self._emptyBuffers()
+
+        def _rename(attrs):
+            d = self.client.renameFile(b"testRenameFile", b"testRenamedFile")
+            self._emptyBuffers()
+            d.addCallback(_testRenamed, attrs)
+            return d
+
+        def _testRenamed(_, attrs):
+            d = self.client.getAttrs(b"testRenamedFile")
+            self._emptyBuffers()
+            d.addCallback(self.assertEqual, attrs)
+
+        return d.addCallback(_rename)
+
+
+    def test_directoryBad(self):
+        d = self.client.getAttrs(b"testMakeDirectory")
+        self._emptyBuffers()
+        return self.assertFailure(d, filetransfer.SFTPError)
+
+
+    def test_directoryCreation(self):
+        d = self.client.makeDirectory(b"testMakeDirectory", {})
+        self._emptyBuffers()
+
+        def _getAttrs(_):
+            d = self.client.getAttrs(b"testMakeDirectory")
+            self._emptyBuffers()
+            return d
+
+        # XXX not until version 4/5
+        # self.assertEqual(filetransfer.FILEXFER_TYPE_DIRECTORY&attrs['type'],
+        #                     filetransfer.FILEXFER_TYPE_DIRECTORY)
+
+        def _removeDirectory(_):
+            d = self.client.removeDirectory(b"testMakeDirectory")
+            self._emptyBuffers()
+            return d
+
+        d.addCallback(_getAttrs)
+        d.addCallback(_removeDirectory)
+        d.addCallback(_getAttrs)
+        return self.assertFailure(d, filetransfer.SFTPError)
+
+
+    def test_openDirectory(self):
+        d = self.client.openDirectory(b'')
+        self._emptyBuffers()
+        files = []
+
+        def _getFiles(openDir):
+            def append(f):
+                files.append(f)
+                return openDir
+            d = defer.maybeDeferred(openDir.next)
+            self._emptyBuffers()
+            d.addCallback(append)
+            d.addCallback(_getFiles)
+            d.addErrback(_close, openDir)
+            return d
+
+        def _checkFiles(ignored):
+            fs = list(list(zip(*files))[0])
+            fs.sort()
+            self.assertEqual(fs,
+                                 [b'.testHiddenFile', b'testDirectory',
+                                  b'testRemoveFile', b'testRenameFile',
+                                  b'testfile1'])
+
+        def _close(_, openDir):
+            d = openDir.close()
+            self._emptyBuffers()
+            return d
+
+        d.addCallback(_getFiles)
+        d.addCallback(_checkFiles)
+        return d
+
+
+    def test_linkDoesntExist(self):
+        d = self.client.getAttrs(b'testLink')
+        self._emptyBuffers()
+        return self.assertFailure(d, filetransfer.SFTPError)
+
+
+    def test_linkSharesAttrs(self):
+        d = self.client.makeLink(b'testLink', b'testfile1')
+        self._emptyBuffers()
+
+        def _getFirstAttrs(_):
+            d = self.client.getAttrs(b'testLink', 1)
+            self._emptyBuffers()
+            return d
+
+        def _getSecondAttrs(firstAttrs):
+            d = self.client.getAttrs(b'testfile1')
+            self._emptyBuffers()
+            d.addCallback(self.assertEqual, firstAttrs)
+            return d
+
+        d.addCallback(_getFirstAttrs)
+        return d.addCallback(_getSecondAttrs)
+
+
+    def test_linkPath(self):
+        d = self.client.makeLink(b'testLink', b'testfile1')
+        self._emptyBuffers()
+
+        def _readLink(_):
+            d = self.client.readLink(b'testLink')
+            self._emptyBuffers()
+            testFile = FilePath(os.getcwd()).preauthChild(self.testDir.path)
+            testFile = testFile.child('testfile1')
+            d.addCallback(
+                self.assertEqual,
+                testFile.path)
+            return d
+
+        def _realPath(_):
+            d = self.client.realPath(b'testLink')
+            self._emptyBuffers()
+            testLink = FilePath(os.getcwd()).preauthChild(self.testDir.path)
+            testLink = testLink.child('testfile1')
+            d.addCallback(
+                self.assertEqual,
+                testLink.path)
+            return d
+
+        d.addCallback(_readLink)
+        d.addCallback(_realPath)
+        return d
+
+
+    def test_extendedRequest(self):
+        d = self.client.extendedRequest(b'testExtendedRequest', b'foo')
+        self._emptyBuffers()
+        d.addCallback(self.assertEqual, b'bar')
+        d.addCallback(self._cbTestExtendedRequest)
+        return d
+
+
+    def _cbTestExtendedRequest(self, ignored):
+        d = self.client.extendedRequest(b'testBadRequest', b'')
+        self._emptyBuffers()
+        return self.assertFailure(d, NotImplementedError)
+
+
+    @defer.inlineCallbacks
+    def test_openDirectoryIterator(self):
+        """
+        Check that the object returned by
+        L{filetransfer.FileTransferClient.openDirectory} can be used
+        as an iterator.
+        """
+
+        # This function is a little more complicated than it would be
+        # normally, since we need to call _emptyBuffers() after
+        # creating any SSH-related Deferreds, but before waiting on
+        # them via yield.
+
+        d = self.client.openDirectory(b'')
+        self._emptyBuffers()
+        openDir = yield d
+
+        filenames = set()
+        try:
+            for f in openDir:
+                self._emptyBuffers()
+                (filename, _, fileattrs) = yield f
+                filenames.add(filename)
+        finally:
+            d = openDir.close()
+            self._emptyBuffers()
+            yield d
+
+        self._emptyBuffers()
+
+        self.assertEqual(filenames,
+                         set([b'.testHiddenFile', b'testDirectory',
+                              b'testRemoveFile', b'testRenameFile',
+                              b'testfile1']))
+
+
+    if _PY37PLUS:
+        test_openDirectoryIterator.skip = (
+            "Broken by PEP 479 and deprecated.")
+
+
+    @defer.inlineCallbacks
+    def test_openDirectoryIteratorDeprecated(self):
+        """
+        Using client.openDirectory as an iterator is deprecated.
+        """
+        d = self.client.openDirectory(b'')
+        self._emptyBuffers()
+        openDir = yield d
+        openDir.next()
+
+        warnings = self.flushWarnings()
+        message = (
+            'Using twisted.conch.ssh.filetransfer.ClientDirectory'
+            ' as an iterator was deprecated in Twisted 18.9.0.'
+            )
+        self.assertEqual(1, len(warnings))
+        self.assertEqual(DeprecationWarning, warnings[0]['category'])
+        self.assertEqual(message, warnings[0]['message'])
+
+
+
+class FakeConn:
+    def sendClose(self, channel):
+        pass
+
+
+class FileTransferCloseTests(unittest.TestCase):
+
+    if not unix:
+        skip = "can't run on non-posix computers"
+
+    def setUp(self):
+        self.avatar = TestAvatar()
+
+    def buildServerConnection(self):
+        # make a server connection
+        conn = connection.SSHConnection()
+        # server connections have a 'self.transport.avatar'.
+        class DummyTransport:
+            def __init__(self):
+                self.transport = self
+            def sendPacket(self, kind, data):
+                pass
+            def logPrefix(self):
+                return 'dummy transport'
+        conn.transport = DummyTransport()
+        conn.transport.avatar = self.avatar
+        return conn
+
+
+    def interceptConnectionLost(self, sftpServer):
+        self.connectionLostFired = False
+        origConnectionLost = sftpServer.connectionLost
+        def connectionLost(reason):
+            self.connectionLostFired = True
+            origConnectionLost(reason)
+        sftpServer.connectionLost = connectionLost
+
+
+    def assertSFTPConnectionLost(self):
+        self.assertTrue(self.connectionLostFired,
+                        "sftpServer's connectionLost was not called")
+
+
+    def test_sessionClose(self):
+        """
+        Closing a session should notify an SFTP subsystem launched by that
+        session.
+        """
+        # make a session
+        testSession = session.SSHSession(conn=FakeConn(), avatar=self.avatar)
+
+        # start an SFTP subsystem on the session
+        testSession.request_subsystem(common.NS(b'sftp'))
+        sftpServer = testSession.client.transport.proto
+
+        # intercept connectionLost so we can check that it's called
+        self.interceptConnectionLost(sftpServer)
+
+        # close session
+        testSession.closeReceived()
+
+        self.assertSFTPConnectionLost()
+
+
+    def test_clientClosesChannelOnConnnection(self):
+        """
+        A client sending CHANNEL_CLOSE should trigger closeReceived on the
+        associated channel instance.
+        """
+        conn = self.buildServerConnection()
+
+        # somehow get a session
+        packet = common.NS(b'session') + struct.pack('>L', 0) * 3
+        conn.ssh_CHANNEL_OPEN(packet)
+        sessionChannel = conn.channels[0]
+
+        sessionChannel.request_subsystem(common.NS(b'sftp'))
+        sftpServer = sessionChannel.client.transport.proto
+        self.interceptConnectionLost(sftpServer)
+
+        # intercept closeReceived
+        self.interceptConnectionLost(sftpServer)
+
+        # close the connection
+        conn.ssh_CHANNEL_CLOSE(struct.pack('>L', 0))
+
+        self.assertSFTPConnectionLost()
+
+
+    def test_stopConnectionServiceClosesChannel(self):
+        """
+        Closing an SSH connection should close all sessions within it.
+        """
+        conn = self.buildServerConnection()
+
+        # somehow get a session
+        packet = common.NS(b'session') + struct.pack('>L', 0) * 3
+        conn.ssh_CHANNEL_OPEN(packet)
+        sessionChannel = conn.channels[0]
+
+        sessionChannel.request_subsystem(common.NS(b'sftp'))
+        sftpServer = sessionChannel.client.transport.proto
+        self.interceptConnectionLost(sftpServer)
+
+        # close the connection
+        conn.serviceStopped()
+
+        self.assertSFTPConnectionLost()
+
+
+
+class ConstantsTests(unittest.TestCase):
+    """
+    Tests for the constants used by the SFTP protocol implementation.
+
+    @ivar filexferSpecExcerpts: Excerpts from the
+        draft-ietf-secsh-filexfer-02.txt (draft) specification of the SFTP
+        protocol.  There are more recent drafts of the specification, but this
+        one describes version 3, which is what conch (and OpenSSH) implements.
+    """
+    if not cryptography:
+        skip = "Cannot run without cryptography"
+
+    filexferSpecExcerpts = [
+        """
+           The following values are defined for packet types.
+
+                #define SSH_FXP_INIT                1
+                #define SSH_FXP_VERSION             2
+                #define SSH_FXP_OPEN                3
+                #define SSH_FXP_CLOSE               4
+                #define SSH_FXP_READ                5
+                #define SSH_FXP_WRITE               6
+                #define SSH_FXP_LSTAT               7
+                #define SSH_FXP_FSTAT               8
+                #define SSH_FXP_SETSTAT             9
+                #define SSH_FXP_FSETSTAT           10
+                #define SSH_FXP_OPENDIR            11
+                #define SSH_FXP_READDIR            12
+                #define SSH_FXP_REMOVE             13
+                #define SSH_FXP_MKDIR              14
+                #define SSH_FXP_RMDIR              15
+                #define SSH_FXP_REALPATH           16
+                #define SSH_FXP_STAT               17
+                #define SSH_FXP_RENAME             18
+                #define SSH_FXP_READLINK           19
+                #define SSH_FXP_SYMLINK            20
+                #define SSH_FXP_STATUS            101
+                #define SSH_FXP_HANDLE            102
+                #define SSH_FXP_DATA              103
+                #define SSH_FXP_NAME              104
+                #define SSH_FXP_ATTRS             105
+                #define SSH_FXP_EXTENDED          200
+                #define SSH_FXP_EXTENDED_REPLY    201
+
+           Additional packet types should only be defined if the protocol
+           version number (see Section ``Protocol Initialization'') is
+           incremented, and their use MUST be negotiated using the version
+           number.  However, the SSH_FXP_EXTENDED and SSH_FXP_EXTENDED_REPLY
+           packets can be used to implement vendor-specific extensions.  See
+           Section ``Vendor-Specific-Extensions'' for more details.
+        """,
+        """
+            The flags bits are defined to have the following values:
+
+                #define SSH_FILEXFER_ATTR_SIZE          0x00000001
+                #define SSH_FILEXFER_ATTR_UIDGID        0x00000002
+                #define SSH_FILEXFER_ATTR_PERMISSIONS   0x00000004
+                #define SSH_FILEXFER_ATTR_ACMODTIME     0x00000008
+                #define SSH_FILEXFER_ATTR_EXTENDED      0x80000000
+
+        """,
+        """
+            The `pflags' field is a bitmask.  The following bits have been
+           defined.
+
+                #define SSH_FXF_READ            0x00000001
+                #define SSH_FXF_WRITE           0x00000002
+                #define SSH_FXF_APPEND          0x00000004
+                #define SSH_FXF_CREAT           0x00000008
+                #define SSH_FXF_TRUNC           0x00000010
+                #define SSH_FXF_EXCL            0x00000020
+        """,
+        """
+            Currently, the following values are defined (other values may be
+           defined by future versions of this protocol):
+
+                #define SSH_FX_OK                            0
+                #define SSH_FX_EOF                           1
+                #define SSH_FX_NO_SUCH_FILE                  2
+                #define SSH_FX_PERMISSION_DENIED             3
+                #define SSH_FX_FAILURE                       4
+                #define SSH_FX_BAD_MESSAGE                   5
+                #define SSH_FX_NO_CONNECTION                 6
+                #define SSH_FX_CONNECTION_LOST               7
+                #define SSH_FX_OP_UNSUPPORTED                8
+        """]
+
+
+    def test_constantsAgainstSpec(self):
+        """
+        The constants used by the SFTP protocol implementation match those
+        found by searching through the spec.
+        """
+        constants = {}
+        for excerpt in self.filexferSpecExcerpts:
+            for line in excerpt.splitlines():
+                m = re.match('^\s*#define SSH_([A-Z_]+)\s+([0-9x]*)\s*$', line)
+                if m:
+                    constants[m.group(1)] = long(m.group(2), 0)
+        self.assertTrue(
+            len(constants) > 0, "No constants found (the test must be buggy).")
+        for k, v in constants.items():
+            self.assertEqual(v, getattr(filetransfer, k))
+
+
+
+class RawPacketDataTests(unittest.TestCase):
+    """
+    Tests for L{filetransfer.FileTransferClient} which explicitly craft certain
+    less common protocol messages to exercise their handling.
+    """
+
+    if not cryptography:
+        skip = "Cannot run without cryptography"
+
+    def setUp(self):
+        self.ftc = filetransfer.FileTransferClient()
+
+
+    def test_packetSTATUS(self):
+        """
+        A STATUS packet containing a result code, a message, and a language is
+        parsed to produce the result of an outstanding request L{Deferred}.
+
+        @see: U{section 9.1<http://tools.ietf.org/html/draft-ietf-secsh-filexfer-13#section-9.1>}
+            of the SFTP Internet-Draft.
+        """
+        d = defer.Deferred()
+        d.addCallback(self._cbTestPacketSTATUS)
+        self.ftc.openRequests[1] = d
+        data = struct.pack('!LL', 1, filetransfer.FX_OK) + common.NS(b'msg') + common.NS(b'lang')
+        self.ftc.packet_STATUS(data)
+        return d
+
+
+    def _cbTestPacketSTATUS(self, result):
+        """
+        Assert that the result is a two-tuple containing the message and
+        language from the STATUS packet.
+        """
+        self.assertEqual(result[0], b'msg')
+        self.assertEqual(result[1], b'lang')
+
+
+    def test_packetSTATUSShort(self):
+        """
+        A STATUS packet containing only a result code can also be parsed to
+        produce the result of an outstanding request L{Deferred}.  Such packets
+        are sent by some SFTP implementations, though not strictly legal.
+
+        @see: U{section 9.1<http://tools.ietf.org/html/draft-ietf-secsh-filexfer-13#section-9.1>}
+            of the SFTP Internet-Draft.
+        """
+        d = defer.Deferred()
+        d.addCallback(self._cbTestPacketSTATUSShort)
+        self.ftc.openRequests[1] = d
+        data = struct.pack('!LL', 1, filetransfer.FX_OK)
+        self.ftc.packet_STATUS(data)
+        return d
+
+
+    def _cbTestPacketSTATUSShort(self, result):
+        """
+        Assert that the result is a two-tuple containing empty strings, since
+        the STATUS packet had neither a message nor a language.
+        """
+        self.assertEqual(result[0], b'')
+        self.assertEqual(result[1], b'')
+
+
+    def test_packetSTATUSWithoutLang(self):
+        """
+        A STATUS packet containing a result code and a message but no language
+        can also be parsed to produce the result of an outstanding request
+        L{Deferred}.  Such packets are sent by some SFTP implementations, though
+        not strictly legal.
+
+        @see: U{section 9.1<http://tools.ietf.org/html/draft-ietf-secsh-filexfer-13#section-9.1>}
+            of the SFTP Internet-Draft.
+        """
+        d = defer.Deferred()
+        d.addCallback(self._cbTestPacketSTATUSWithoutLang)
+        self.ftc.openRequests[1] = d
+        data = struct.pack('!LL', 1, filetransfer.FX_OK) + common.NS(b'msg')
+        self.ftc.packet_STATUS(data)
+        return d
+
+
+    def _cbTestPacketSTATUSWithoutLang(self, result):
+        """
+        Assert that the result is a two-tuple containing the message from the
+        STATUS packet and an empty string, since the language was missing.
+        """
+        self.assertEqual(result[0], b'msg')
+        self.assertEqual(result[1], b'')