shell bypass 403
UnknownSec Shell
:
/
proc
/
thread-self
/
root
/
usr
/
lib
/
python3
/
dist-packages
/
twisted
/
conch
/
scripts
/ [
drwxr-xr-x
]
upload
mass deface
mass delete
console
info server
name :
cftp.py
# -*- test-case-name: twisted.conch.test.test_cftp -*- # Copyright (c) Twisted Matrix Laboratories. # See LICENSE for details. """ Implementation module for the I{cftp} command. """ import fcntl import fnmatch import getpass import glob import os import pwd import stat import struct import sys import tty from typing import List, Optional, TextIO, Union from twisted.conch.client import connect, default, options from twisted.conch.ssh import channel, common, connection, filetransfer from twisted.internet import defer, reactor, stdio, utils from twisted.protocols import basic from twisted.python import failure, log, usage from twisted.python.filepath import FilePath class ClientOptions(options.ConchOptions): synopsis = """Usage: cftp [options] [user@]host cftp [options] [user@]host[:dir[/]] cftp [options] [user@]host[:file [localfile]] """ longdesc = ( "cftp is a client for logging into a remote machine and " "executing commands to send and receive file information" ) optParameters: List[List[Optional[Union[str, int]]]] = [ ["buffersize", "B", 32768, "Size of the buffer to use for sending/receiving."], ["batchfile", "b", None, "File to read commands from, or '-' for stdin."], ["requests", "R", 5, "Number of requests to make before waiting for a reply."], ["subsystem", "s", "sftp", "Subsystem/server program to connect to."], ] compData = usage.Completions( descriptions={"buffersize": "Size of send/receive buffer (default: 32768)"}, extraActions=[ usage.CompleteUserAtHost(), usage.CompleteFiles(descr="local file"), ], ) def parseArgs(self, host, localPath=None): self["remotePath"] = "" if ":" in host: host, self["remotePath"] = host.split(":", 1) self["remotePath"].rstrip("/") self["host"] = host self["localPath"] = localPath def run(): args = sys.argv[1:] if "-l" in args: # cvs is an idiot i = args.index("-l") args = args[i : i + 2] + args del args[i + 2 : i + 4] options = ClientOptions() try: options.parseOptions(args) except usage.UsageError as u: print("ERROR: %s" % u) sys.exit(1) if options["log"]: realout = sys.stdout log.startLogging(sys.stderr) sys.stdout = realout else: log.discardLogs() doConnect(options) reactor.run() def handleError(): global exitStatus exitStatus = 2 try: reactor.stop() except BaseException: pass log.err(failure.Failure()) raise def doConnect(options): if "@" in options["host"]: options["user"], options["host"] = options["host"].split("@", 1) host = options["host"] if not options["user"]: options["user"] = getpass.getuser() if not options["port"]: options["port"] = 22 else: options["port"] = int(options["port"]) host = options["host"] port = options["port"] conn = SSHConnection() conn.options = options vhk = default.verifyHostKey uao = default.SSHUserAuthClient(options["user"], options, conn) connect.connect(host, port, options, vhk, uao).addErrback(_ebExit) def _ebExit(f): if hasattr(f.value, "value"): s = f.value.value else: s = str(f) print(s) try: reactor.stop() except BaseException: pass def _ignore(*args): pass class FileWrapper: def __init__(self, f): self.f = f self.total = 0.0 f.seek(0, 2) # seek to the end self.size = f.tell() def __getattr__(self, attr): return getattr(self.f, attr) class StdioClient(basic.LineReceiver): _pwd = pwd ps = "cftp> " delimiter = b"\n" reactor = reactor def __init__(self, client, f=None): self.client = client self.currentDirectory = "" self.file = f self.useProgressBar = (not f and 1) or 0 def connectionMade(self): self.client.realPath("").addCallback(self._cbSetCurDir) def _cbSetCurDir(self, path): self.currentDirectory = path self._newLine() def _writeToTransport(self, msg): if isinstance(msg, str): msg = msg.encode("utf-8") return self.transport.write(msg) def lineReceived(self, line): if self.client.transport.localClosed: return if isinstance(line, bytes): line = line.decode("utf-8") log.msg("got line %s" % line) line = line.lstrip() if not line: self._newLine() return if self.file and line.startswith("-"): self.ignoreErrors = 1 line = line[1:] else: self.ignoreErrors = 0 d = self._dispatchCommand(line) if d is not None: d.addCallback(self._cbCommand) d.addErrback(self._ebCommand) def _dispatchCommand(self, line): if " " in line: command, rest = line.split(" ", 1) rest = rest.lstrip() else: command, rest = line, "" if command.startswith("!"): # command f = self.cmd_EXEC rest = (command[1:] + " " + rest).strip() else: command = command.upper() log.msg("looking up cmd %s" % command) f = getattr(self, "cmd_%s" % command, None) if f is not None: return defer.maybeDeferred(f, rest) else: errMsg = "No command called `%s'" % (command) self._ebCommand(failure.Failure(NotImplementedError(errMsg))) self._newLine() def _printFailure(self, f): log.msg(f) e = f.trap(NotImplementedError, filetransfer.SFTPError, OSError, IOError) if e == NotImplementedError: self._writeToTransport(self.cmd_HELP("")) elif e == filetransfer.SFTPError: errMsg = "remote error %i: %s\n" % (f.value.code, f.value.message) self._writeToTransport(errMsg) elif e in (OSError, IOError): errMsg = "local error %i: %s\n" % (f.value.errno, f.value.strerror) self._writeToTransport(errMsg) def _newLine(self): if self.client.transport.localClosed: return self._writeToTransport(self.ps) self.ignoreErrors = 0 if self.file: l = self.file.readline() if not l: self.client.transport.loseConnection() else: self._writeToTransport(l) self.lineReceived(l.strip()) def _cbCommand(self, result): if result is not None: if isinstance(result, str): result = result.encode("utf-8") self._writeToTransport(result) if not result.endswith(b"\n"): self._writeToTransport(b"\n") self._newLine() def _ebCommand(self, f): self._printFailure(f) if self.file and not self.ignoreErrors: self.client.transport.loseConnection() self._newLine() def cmd_CD(self, path): path, rest = self._getFilename(path) if not path.endswith("/"): path += "/" newPath = path and os.path.join(self.currentDirectory, path) or "" d = self.client.openDirectory(newPath) d.addCallback(self._cbCd) d.addErrback(self._ebCommand) return d def _cbCd(self, directory): directory.close() d = self.client.realPath(directory.name) d.addCallback(self._cbCurDir) return d def _cbCurDir(self, path): self.currentDirectory = path def cmd_CHGRP(self, rest): grp, rest = rest.split(None, 1) path, rest = self._getFilename(rest) grp = int(grp) d = self.client.getAttrs(path) d.addCallback(self._cbSetUsrGrp, path, grp=grp) return d def cmd_CHMOD(self, rest): mod, rest = rest.split(None, 1) path, rest = self._getFilename(rest) mod = int(mod, 8) d = self.client.setAttrs(path, {"permissions": mod}) d.addCallback(_ignore) return d def cmd_CHOWN(self, rest): usr, rest = rest.split(None, 1) path, rest = self._getFilename(rest) usr = int(usr) d = self.client.getAttrs(path) d.addCallback(self._cbSetUsrGrp, path, usr=usr) return d def _cbSetUsrGrp(self, attrs, path, usr=None, grp=None): new = {} new["uid"] = (usr is not None) and usr or attrs["uid"] new["gid"] = (grp is not None) and grp or attrs["gid"] d = self.client.setAttrs(path, new) d.addCallback(_ignore) return d def cmd_GET(self, rest): remote, rest = self._getFilename(rest) if "*" in remote or "?" in remote: # wildcard if rest: local, rest = self._getFilename(rest) if not os.path.isdir(local): return "Wildcard get with non-directory target." else: local = b"" d = self._remoteGlob(remote) d.addCallback(self._cbGetMultiple, local) return d if rest: local, rest = self._getFilename(rest) else: local = os.path.split(remote)[1] log.msg((remote, local)) lf = open(local, "wb", 0) path = FilePath(self.currentDirectory).child(remote) d = self.client.openFile(path.path, filetransfer.FXF_READ, {}) d.addCallback(self._cbGetOpenFile, lf) d.addErrback(self._ebCloseLf, lf) return d def _cbGetMultiple(self, files, local): # XXX this can be optimized for times w/o progress bar return self._cbGetMultipleNext(None, files, local) def _cbGetMultipleNext(self, res, files, local): if isinstance(res, failure.Failure): self._printFailure(res) elif res: self._writeToTransport(res) if not res.endswith("\n"): self._writeToTransport("\n") if not files: return f = files.pop(0)[0] lf = open(os.path.join(local, os.path.split(f)[1]), "wb", 0) path = FilePath(self.currentDirectory).child(f) d = self.client.openFile(path.path, filetransfer.FXF_READ, {}) d.addCallback(self._cbGetOpenFile, lf) d.addErrback(self._ebCloseLf, lf) d.addBoth(self._cbGetMultipleNext, files, local) return d def _ebCloseLf(self, f, lf): lf.close() return f def _cbGetOpenFile(self, rf, lf): return rf.getAttrs().addCallback(self._cbGetFileSize, rf, lf) def _cbGetFileSize(self, attrs, rf, lf): if not stat.S_ISREG(attrs["permissions"]): rf.close() lf.close() return "Can't get non-regular file: %s" % rf.name rf.size = attrs["size"] bufferSize = self.client.transport.conn.options["buffersize"] numRequests = self.client.transport.conn.options["requests"] rf.total = 0.0 dList = [] chunks = [] startTime = self.reactor.seconds() for i in range(numRequests): d = self._cbGetRead("", rf, lf, chunks, 0, bufferSize, startTime) dList.append(d) dl = defer.DeferredList(dList, fireOnOneErrback=1) dl.addCallback(self._cbGetDone, rf, lf) return dl def _getNextChunk(self, chunks): end = 0 for chunk in chunks: if end == "eof": return # nothing more to get if end != chunk[0]: i = chunks.index(chunk) chunks.insert(i, (end, chunk[0])) return (end, chunk[0] - end) end = chunk[1] bufSize = int(self.client.transport.conn.options["buffersize"]) chunks.append((end, end + bufSize)) return (end, bufSize) def _cbGetRead(self, data, rf, lf, chunks, start, size, startTime): if data and isinstance(data, failure.Failure): log.msg("get read err: %s" % data) reason = data reason.trap(EOFError) i = chunks.index((start, start + size)) del chunks[i] chunks.insert(i, (start, "eof")) elif data: log.msg("get read data: %i" % len(data)) lf.seek(start) lf.write(data) if len(data) != size: log.msg("got less than we asked for: %i < %i" % (len(data), size)) i = chunks.index((start, start + size)) del chunks[i] chunks.insert(i, (start, start + len(data))) rf.total += len(data) if self.useProgressBar: self._printProgressBar(rf, startTime) chunk = self._getNextChunk(chunks) if not chunk: return else: start, length = chunk log.msg("asking for %i -> %i" % (start, start + length)) d = rf.readChunk(start, length) d.addBoth(self._cbGetRead, rf, lf, chunks, start, length, startTime) return d def _cbGetDone(self, ignored, rf, lf): log.msg("get done") rf.close() lf.close() if self.useProgressBar: self._writeToTransport("\n") return f"Transferred {rf.name} to {lf.name}" def cmd_PUT(self, rest): """ Do an upload request for a single local file or a globing expression. @param rest: Requested command line for the PUT command. @type rest: L{str} @return: A deferred which fires with L{None} when transfer is done. @rtype: L{defer.Deferred} """ local, rest = self._getFilename(rest) # FIXME: https://twistedmatrix.com/trac/ticket/7241 # Use a better check for globbing expression. if "*" in local or "?" in local: if rest: remote, rest = self._getFilename(rest) remote = os.path.join(self.currentDirectory, remote) else: remote = "" files = glob.glob(local) return self._putMultipleFiles(files, remote) else: if rest: remote, rest = self._getFilename(rest) else: remote = os.path.split(local)[1] return self._putSingleFile(local, remote) def _putSingleFile(self, local, remote): """ Perform an upload for a single file. @param local: Path to local file. @type local: L{str}. @param remote: Remote path for the request relative to current working directory. @type remote: L{str} @return: A deferred which fires when transfer is done. """ return self._cbPutMultipleNext(None, [local], remote, single=True) def _putMultipleFiles(self, files, remote): """ Perform an upload for a list of local files. @param files: List of local files. @type files: C{list} of L{str}. @param remote: Remote path for the request relative to current working directory. @type remote: L{str} @return: A deferred which fires when transfer is done. """ return self._cbPutMultipleNext(None, files, remote) def _cbPutMultipleNext(self, previousResult, files, remotePath, single=False): """ Perform an upload for the next file in the list of local files. @param previousResult: Result form previous file form the list. @type previousResult: L{str} @param files: List of local files. @type files: C{list} of L{str} @param remotePath: Remote path for the request relative to current working directory. @type remotePath: L{str} @param single: A flag which signals if this is a transfer for a single file in which case we use the exact remote path @type single: L{bool} @return: A deferred which fires when transfer is done. """ if isinstance(previousResult, failure.Failure): self._printFailure(previousResult) elif previousResult: if isinstance(previousResult, str): previousResult = previousResult.encode("utf-8") self._writeToTransport(previousResult) if not previousResult.endswith(b"\n"): self._writeToTransport(b"\n") currentFile = None while files and not currentFile: try: currentFile = files.pop(0) localStream = open(currentFile, "rb") except BaseException: self._printFailure(failure.Failure()) currentFile = None # No more files to transfer. if not currentFile: return None if single: remote = remotePath else: name = os.path.split(currentFile)[1] remote = os.path.join(remotePath, name) log.msg((name, remote, remotePath)) d = self._putRemoteFile(localStream, remote) d.addBoth(self._cbPutMultipleNext, files, remotePath) return d def _putRemoteFile(self, localStream, remotePath): """ Do an upload request. @param localStream: Local stream from where data is read. @type localStream: File like object. @param remotePath: Remote path for the request relative to current working directory. @type remotePath: L{str} @return: A deferred which fires when transfer is done. """ remote = os.path.join(self.currentDirectory, remotePath) flags = filetransfer.FXF_WRITE | filetransfer.FXF_CREAT | filetransfer.FXF_TRUNC d = self.client.openFile(remote, flags, {}) d.addCallback(self._cbPutOpenFile, localStream) d.addErrback(self._ebCloseLf, localStream) return d def _cbPutOpenFile(self, rf, lf): numRequests = self.client.transport.conn.options["requests"] if self.useProgressBar: lf = FileWrapper(lf) dList = [] chunks = [] startTime = self.reactor.seconds() for i in range(numRequests): d = self._cbPutWrite(None, rf, lf, chunks, startTime) if d: dList.append(d) dl = defer.DeferredList(dList, fireOnOneErrback=1) dl.addCallback(self._cbPutDone, rf, lf) return dl def _cbPutWrite(self, ignored, rf, lf, chunks, startTime): chunk = self._getNextChunk(chunks) start, size = chunk lf.seek(start) data = lf.read(size) if self.useProgressBar: lf.total += len(data) self._printProgressBar(lf, startTime) if data: d = rf.writeChunk(start, data) d.addCallback(self._cbPutWrite, rf, lf, chunks, startTime) return d else: return def _cbPutDone(self, ignored, rf, lf): lf.close() rf.close() if self.useProgressBar: self._writeToTransport("\n") return f"Transferred {lf.name} to {rf.name}" def cmd_LCD(self, path): os.chdir(path) def cmd_LN(self, rest): linkpath, rest = self._getFilename(rest) targetpath, rest = self._getFilename(rest) linkpath, targetpath = map( lambda x: os.path.join(self.currentDirectory, x), (linkpath, targetpath) ) return self.client.makeLink(linkpath, targetpath).addCallback(_ignore) def cmd_LS(self, rest): # possible lines: # ls current directory # ls name_of_file that file # ls name_of_directory that directory # ls some_glob_string current directory, globbed for that string options = [] rest = rest.split() while rest and rest[0] and rest[0][0] == "-": opts = rest.pop(0)[1:] for o in opts: if o == "l": options.append("verbose") elif o == "a": options.append("all") rest = " ".join(rest) path, rest = self._getFilename(rest) if not path: fullPath = self.currentDirectory + "/" else: fullPath = os.path.join(self.currentDirectory, path) d = self._remoteGlob(fullPath) d.addCallback(self._cbDisplayFiles, options) return d def _cbDisplayFiles(self, files, options): files.sort() if "all" not in options: files = [f for f in files if not f[0].startswith(b".")] if "verbose" in options: lines = [f[1] for f in files] else: lines = [f[0] for f in files] if not lines: return None else: return b"\n".join(lines) def cmd_MKDIR(self, path): path, rest = self._getFilename(path) path = os.path.join(self.currentDirectory, path) return self.client.makeDirectory(path, {}).addCallback(_ignore) def cmd_RMDIR(self, path): path, rest = self._getFilename(path) path = os.path.join(self.currentDirectory, path) return self.client.removeDirectory(path).addCallback(_ignore) def cmd_LMKDIR(self, path): os.system("mkdir %s" % path) def cmd_RM(self, path): path, rest = self._getFilename(path) path = os.path.join(self.currentDirectory, path) return self.client.removeFile(path).addCallback(_ignore) def cmd_LLS(self, rest): os.system("ls %s" % rest) def cmd_RENAME(self, rest): oldpath, rest = self._getFilename(rest) newpath, rest = self._getFilename(rest) oldpath, newpath = map( lambda x: os.path.join(self.currentDirectory, x), (oldpath, newpath) ) return self.client.renameFile(oldpath, newpath).addCallback(_ignore) def cmd_EXIT(self, ignored): self.client.transport.loseConnection() cmd_QUIT = cmd_EXIT def cmd_VERSION(self, ignored): version = "SFTP version %i" % self.client.version if isinstance(version, str): version = version.encode("utf-8") return version def cmd_HELP(self, ignored): return """Available commands: cd path Change remote directory to 'path'. chgrp gid path Change gid of 'path' to 'gid'. chmod mode path Change mode of 'path' to 'mode'. chown uid path Change uid of 'path' to 'uid'. exit Disconnect from the server. get remote-path [local-path] Get remote file. help Get a list of available commands. lcd path Change local directory to 'path'. lls [ls-options] [path] Display local directory listing. lmkdir path Create local directory. ln linkpath targetpath Symlink remote file. lpwd Print the local working directory. ls [-l] [path] Display remote directory listing. mkdir path Create remote directory. progress Toggle progress bar. put local-path [remote-path] Put local file. pwd Print the remote working directory. quit Disconnect from the server. rename oldpath newpath Rename remote file. rmdir path Remove remote directory. rm path Remove remote file. version Print the SFTP version. ? Synonym for 'help'. """ def cmd_PWD(self, ignored): return self.currentDirectory def cmd_LPWD(self, ignored): return os.getcwd() def cmd_PROGRESS(self, ignored): self.useProgressBar = not self.useProgressBar return "%ssing progess bar." % (self.useProgressBar and "U" or "Not u") def cmd_EXEC(self, rest): """ Run C{rest} using the user's shell (or /bin/sh if they do not have one). """ shell = self._pwd.getpwnam(getpass.getuser())[6] if not shell: shell = "/bin/sh" if rest: cmds = ["-c", rest] return utils.getProcessOutput(shell, cmds, errortoo=1) else: os.system(shell) # accessory functions def _remoteGlob(self, fullPath): log.msg("looking up %s" % fullPath) head, tail = os.path.split(fullPath) if "*" in tail or "?" in tail: glob = 1 else: glob = 0 if tail and not glob: # could be file or directory # try directory first d = self.client.openDirectory(fullPath) d.addCallback(self._cbOpenList, "") d.addErrback(self._ebNotADirectory, head, tail) else: d = self.client.openDirectory(head) d.addCallback(self._cbOpenList, tail) return d def _cbOpenList(self, directory, glob): files = [] d = directory.read() d.addBoth(self._cbReadFile, files, directory, glob) return d def _ebNotADirectory(self, reason, path, glob): d = self.client.openDirectory(path) d.addCallback(self._cbOpenList, glob) return d def _cbReadFile(self, files, matchedFiles, directory, glob): if not isinstance(files, failure.Failure): if glob: glob = glob.encode("utf-8") matchedFiles.extend([f for f in files if fnmatch.fnmatch(f[0], glob)]) else: matchedFiles.extend(files) d = directory.read() d.addBoth(self._cbReadFile, matchedFiles, directory, glob) return d else: reason = files reason.trap(EOFError) directory.close() return matchedFiles def _abbrevSize(self, size): # from http://mail.python.org/pipermail/python-list/1999-December/018395.html _abbrevs = [ (1 << 50, "PB"), (1 << 40, "TB"), (1 << 30, "GB"), (1 << 20, "MB"), (1 << 10, "kB"), (1, "B"), ] for factor, suffix in _abbrevs: if size > factor: break return "%.1f" % (size / factor) + suffix def _abbrevTime(self, t): if t > 3600: # 1 hour hours = int(t / 3600) t -= 3600 * hours mins = int(t / 60) t -= 60 * mins return "%i:%02i:%02i" % (hours, mins, t) else: mins = int(t / 60) t -= 60 * mins return "%02i:%02i" % (mins, t) def _printProgressBar(self, f, startTime): """ Update a console progress bar on this L{StdioClient}'s transport, based on the difference between the start time of the operation and the current time according to the reactor, and appropriate to the size of the console window. @param f: a wrapper around the file which is being written or read @type f: L{FileWrapper} @param startTime: The time at which the operation being tracked began. @type startTime: L{float} """ diff = self.reactor.seconds() - startTime total = f.total try: winSize = struct.unpack("4H", fcntl.ioctl(0, tty.TIOCGWINSZ, "12345679")) except OSError: winSize = [None, 80] if diff == 0.0: speed = 0.0 else: speed = total / diff if speed: timeLeft = (f.size - total) / speed else: timeLeft = 0 front = f.name if f.size: percentage = (total / f.size) * 100 else: percentage = 100 back = "%3i%% %s %sps %s " % ( percentage, self._abbrevSize(total), self._abbrevSize(speed), self._abbrevTime(timeLeft), ) spaces = (winSize[1] - (len(front) + len(back) + 1)) * " " command = f"\r{front}{spaces}{back}" self._writeToTransport(command) def _getFilename(self, line): """ Parse line received as command line input and return first filename together with the remaining line. @param line: Arguments received from command line input. @type line: L{str} @return: Tupple with filename and rest. Return empty values when no path was not found. @rtype: C{tupple} """ line = line.strip() if not line: return "", "" if line[0] in "'\"": ret = [] line = list(line) try: for i in range(1, len(line)): c = line[i] if c == line[0]: return "".join(ret), "".join(line[i + 1 :]).lstrip() elif c == "\\": # quoted character del line[i] if line[i] not in "'\"\\": raise IndexError(f"bad quote: \\{line[i]}") ret.append(line[i]) else: ret.append(line[i]) except IndexError: raise IndexError("unterminated quote") ret = line.split(None, 1) if len(ret) == 1: return ret[0], "" else: return ret[0], ret[1] setattr(StdioClient, "cmd_?", StdioClient.cmd_HELP) class SSHConnection(connection.SSHConnection): def serviceStarted(self): self.openChannel(SSHSession()) class SSHSession(channel.SSHChannel): name: bytes = b"session" stderr: TextIO = sys.stderr def channelOpen(self, foo): log.msg("session %s open" % self.id) if self.conn.options["subsystem"].startswith("/"): request = "exec" else: request = "subsystem" d = self.conn.sendRequest( self, request, common.NS(self.conn.options["subsystem"]), wantReply=1 ) d.addCallback(self._cbSubsystem) d.addErrback(_ebExit) def _cbSubsystem(self, result): self.client = filetransfer.FileTransferClient() self.client.makeConnection(self) self.dataReceived = self.client.dataReceived f = None if self.conn.options["batchfile"]: fn = self.conn.options["batchfile"] if fn != "-": f = open(fn) self.stdio = stdio.StandardIO(StdioClient(self.client, f)) def extReceived(self, t: int, data: bytes) -> None: if t == connection.EXTENDED_DATA_STDERR: log.msg("got %s stderr data" % len(data)) # RFC 4251 # ======== # Strings are also used to store text. In that case, US-ASCII is # used for internal names, and ISO-10646 UTF-8 for text that might # be displayed to the user. The terminating null character SHOULD # NOT normally be stored in the string. For example: the US-ASCII # string "testing" is represented as 00 00 00 07 t e s t i n g. # The UTF-8 mapping does not alter the encoding of US-ASCII # characters. # # RFC 4254 # ======== # Additionally, some channels can transfer several types of data. An # example of this is stderr data from interactive sessions. Such data # can be passed with SSH_MSG_CHANNEL_EXTENDED_DATA messages, where a # separate integer specifies the type of data. The available types and # their interpretation depend on the type of channel. # # byte SSH_MSG_CHANNEL_EXTENDED_DATA # uint32 recipient channel # uint32 data_type_code # string data # # Data sent with these messages consumes the same window as ordinary # data. # # Currently, only the following type is defined. Note that the value # for the 'data_type_code' is given in decimal format for readability, # but the values are actually uint32 values. # # Symbolic name data_type_code # ------------- -------------- # SSH_EXTENDED_DATA_STDERR 1 # # (end of RFC quotations) # # Here we decode the stderr bytes as UTF-8 and handle errors by # representing undecodeable bytes with a certain escape scheme. # There is no guarantee that the peer is sending UTF-8 encoded # bytes but if they are not it is complex to determine what # encoding they _are_ sending. The standard says nothing about # how these bytes should be decoded because the standard probably # doesn't think they should be decoded at all - just handle them # as bytes! However, our stderr is a text-mode file so we *must* # decode them to be able to write them out at all. And even if we # had a binary-mode file we would still /probably/ want to write # bytes in a *known* encoding to it. # # Perhaps in the future we can somehow inspect LANG or LC_* in the # remote execution environment (but I'm not sure how) and use that # as a hint about which encoding to use for decoding here. # Meanwhile, UTF-8 is the de facto universal interoperable # encoding so: use it. self.stderr.write(data.decode("utf-8", "backslashreplace")) self.stderr.flush() def eofReceived(self): log.msg("got eof") self.stdio.loseWriteConnection() def closeReceived(self): log.msg("remote side closed %s" % self) self.conn.sendClose(self) def closed(self): try: reactor.stop() except BaseException: pass def stopWriting(self): self.stdio.pauseProducing() def startWriting(self): self.stdio.resumeProducing() if __name__ == "__main__": run()
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