From: david-sarah Date: Fri, 29 Jul 2011 23:31:02 +0000 (-0700) Subject: SFTP: write an error message to standard error for unrecognized shell commands. Chang... X-Git-Url: https://git.rkrishnan.org/nxhtml.html?a=commitdiff_plain;h=a2699ea6f635c9920e159b4b10fbc82b473dbc08;p=tahoe-lafs%2Ftahoe-lafs.git SFTP: write an error message to standard error for unrecognized shell commands. Change the existing message for shell sessions to be written to standard error, and refactor some duplicated code. Also change the lines of the error messages to end in CRLF, and take into account Kevan's review comments. fixes #1442, #1446 --- diff --git a/src/allmydata/frontends/sftpd.py b/src/allmydata/frontends/sftpd.py index f7d345ba..7301f281 100644 --- a/src/allmydata/frontends/sftpd.py +++ b/src/allmydata/frontends/sftpd.py @@ -1868,10 +1868,7 @@ class ShellSession(PrefixingLogMixin): if hasattr(protocol, 'transport') and protocol.transport is None: protocol.transport = FakeTransport() # work around Twisted bug - d = defer.succeed(None) - d.addCallback(lambda ign: protocol.write("This server supports only SFTP, not shell sessions.\n")) - d.addCallback(lambda ign: protocol.processEnded(Reason(ProcessTerminated(exitCode=1)))) - return d + return self._unsupported(protocol) def execCommand(self, protocol, cmd): self.log(".execCommand(%r, %r)" % (protocol, cmd), level=OPERATIONAL) @@ -1881,11 +1878,19 @@ class ShellSession(PrefixingLogMixin): d = defer.succeed(None) if cmd == "df -P -k /": d.addCallback(lambda ign: protocol.write( - "Filesystem 1024-blocks Used Available Capacity Mounted on\n" - "tahoe 628318530 314159265 314159265 50% /\n")) + "Filesystem 1024-blocks Used Available Capacity Mounted on\r\n" + "tahoe 628318530 314159265 314159265 50% /\r\n")) d.addCallback(lambda ign: protocol.processEnded(Reason(ProcessDone(None)))) else: - d.addCallback(lambda ign: protocol.processEnded(Reason(ProcessTerminated(exitCode=1)))) + d.addCallback(lambda ign: self._unsupported(protocol)) + return d + + def _unsupported(self, protocol): + d = defer.succeed(None) + d.addCallback(lambda ign: protocol.errReceived( + "This server supports only the SFTP protocol. It does not support SCP,\r\n" + "interactive shell sessions, or commands other than one needed by sshfs.\r\n")) + d.addCallback(lambda ign: protocol.processEnded(Reason(ProcessTerminated(exitCode=1)))) return d def windowChanged(self, newWindowSize): diff --git a/src/allmydata/test/test_sftp.py b/src/allmydata/test/test_sftp.py index b648154e..76838b04 100644 --- a/src/allmydata/test/test_sftp.py +++ b/src/allmydata/test/test_sftp.py @@ -1327,49 +1327,69 @@ class Handler(GridTestMixin, ShouldFailMixin, ReallyEqualMixin, unittest.TestCas return d def test_execCommand_and_openShell(self): - class FakeProtocol: + class MockProtocol: def __init__(self): self.output = "" + self.error = "" self.reason = None + def write(self, data): + return self.outReceived(data) + + def outReceived(self, data): self.output += data return defer.succeed(None) + + def errReceived(self, data): + self.error += data + return defer.succeed(None) + def processEnded(self, reason): self.reason = reason return defer.succeed(None) + def _lines_end_in_crlf(s): + return s.replace('\r\n', '').find('\n') == -1 and s.endswith('\r\n') + d = self._set_up("execCommand_and_openShell") d.addCallback(lambda ign: conch_interfaces.ISession(self.handler)) def _exec_df(session): - protocol = FakeProtocol() + protocol = MockProtocol() d2 = session.execCommand(protocol, "df -P -k /") d2.addCallback(lambda ign: self.failUnlessIn("1024-blocks", protocol.output)) + d2.addCallback(lambda ign: self.failUnless(_lines_end_in_crlf(protocol.output), protocol.output)) + d2.addCallback(lambda ign: self.failUnlessEqual(protocol.error, "")) d2.addCallback(lambda ign: self.failUnless(isinstance(protocol.reason.value, ProcessDone))) d2.addCallback(lambda ign: session.eofReceived()) d2.addCallback(lambda ign: session.closed()) return d2 d.addCallback(_exec_df) + def _check_unsupported(protocol): + d2 = defer.succeed(None) + d2.addCallback(lambda ign: self.failUnlessEqual(protocol.output, "")) + d2.addCallback(lambda ign: self.failUnlessIn("only the SFTP protocol", protocol.error)) + d2.addCallback(lambda ign: self.failUnless(_lines_end_in_crlf(protocol.error), protocol.error)) + d2.addCallback(lambda ign: self.failUnless(isinstance(protocol.reason.value, ProcessTerminated))) + d2.addCallback(lambda ign: self.failUnlessEqual(protocol.reason.value.exitCode, 1)) + return d2 + d.addCallback(lambda ign: conch_interfaces.ISession(self.handler)) def _exec_error(session): - protocol = FakeProtocol() + protocol = MockProtocol() d2 = session.execCommand(protocol, "error") d2.addCallback(lambda ign: session.windowChanged(None)) - d2.addCallback(lambda ign: self.failUnlessEqual("", protocol.output)) - d2.addCallback(lambda ign: self.failUnless(isinstance(protocol.reason.value, ProcessTerminated))) - d2.addCallback(lambda ign: self.failUnlessEqual(protocol.reason.value.exitCode, 1)) + d2.addCallback(lambda ign: _check_unsupported(protocol)) d2.addCallback(lambda ign: session.closed()) return d2 d.addCallback(_exec_error) d.addCallback(lambda ign: conch_interfaces.ISession(self.handler)) def _openShell(session): - protocol = FakeProtocol() + protocol = MockProtocol() d2 = session.openShell(protocol) - d2.addCallback(lambda ign: self.failUnlessIn("only SFTP", protocol.output)) - d2.addCallback(lambda ign: self.failUnless(isinstance(protocol.reason.value, ProcessTerminated))) - d2.addCallback(lambda ign: self.failUnlessEqual(protocol.reason.value.exitCode, 1)) + d2.addCallback(lambda ign: _check_unsupported(protocol)) d2.addCallback(lambda ign: session.closed()) return d2 d.addCallback(_openShell)