-import tempfile
+import heapq, traceback, array, stat, struct
+from types import NoneType
+from stat import S_IFREG, S_IFDIR
+from time import time, strftime, localtime
+
from zope.interface import implements
from twisted.python import components
from twisted.application import service, strports
-from twisted.internet import defer
-from twisted.internet.interfaces import IConsumer
from twisted.conch.ssh import factory, keys, session
-from twisted.conch.interfaces import ISFTPServer, ISFTPFile, IConchUser
+from twisted.conch.ssh.filetransfer import FileTransferServer, SFTPError, \
+ FX_NO_SUCH_FILE, FX_OP_UNSUPPORTED, FX_PERMISSION_DENIED, FX_EOF, \
+ FX_BAD_MESSAGE, FX_FAILURE, FX_OK
+from twisted.conch.ssh.filetransfer import FXF_READ, FXF_WRITE, FXF_APPEND, \
+ FXF_CREAT, FXF_TRUNC, FXF_EXCL
+from twisted.conch.interfaces import ISFTPServer, ISFTPFile, IConchUser, ISession
from twisted.conch.avatar import ConchUser
from twisted.conch.openssh_compat import primes
-from twisted.conch import ls
from twisted.cred import portal
+from twisted.internet.error import ProcessDone, ProcessTerminated
+from twisted.python.failure import Failure
+from twisted.internet.interfaces import ITransport
+
+from twisted.internet import defer
+from twisted.internet.interfaces import IConsumer
+from foolscap.api import eventually
+from allmydata.util import deferredutil
-from allmydata.interfaces import IDirectoryNode, ExistingChildError, \
- NoSuchChildError
+from allmydata.util.assertutil import _assert, precondition
+from allmydata.util.consumer import download_to_data
+from allmydata.interfaces import IFileNode, IDirectoryNode, ExistingChildError, \
+ NoSuchChildError, ChildOfWrongTypeError
+from allmydata.mutable.common import NotWriteableError
+from allmydata.mutable.publish import MutableFileHandle
from allmydata.immutable.upload import FileHandle
+from allmydata.dirnode import update_metadata
+from allmydata.util.fileutil import EncryptedTemporaryFile
+
+noisy = True
+use_foolscap_logging = True
+
+from allmydata.util.log import NOISY, OPERATIONAL, WEIRD, \
+ msg as _msg, err as _err, PrefixingLogMixin as _PrefixingLogMixin
+
+if use_foolscap_logging:
+ (logmsg, logerr, PrefixingLogMixin) = (_msg, _err, _PrefixingLogMixin)
+else: # pragma: no cover
+ def logmsg(s, level=None):
+ print s
+ def logerr(s, level=None):
+ print s
+ class PrefixingLogMixin:
+ def __init__(self, facility=None, prefix=''):
+ self.prefix = prefix
+ def log(self, s, level=None):
+ print "%r %s" % (self.prefix, s)
+
+
+def eventually_callback(d):
+ return lambda res: eventually(d.callback, res)
+
+def eventually_errback(d):
+ return lambda err: eventually(d.errback, err)
+
+
+def _utf8(x):
+ if isinstance(x, unicode):
+ return x.encode('utf-8')
+ if isinstance(x, str):
+ return x
+ return repr(x)
+
+
+def _to_sftp_time(t):
+ """SFTP times are unsigned 32-bit integers representing UTC seconds
+ (ignoring leap seconds) since the Unix epoch, January 1 1970 00:00 UTC.
+ A Tahoe time is the corresponding float."""
+ return long(t) & 0xFFFFFFFFL
+
+
+def _convert_error(res, request):
+ """If res is not a Failure, return it, otherwise reraise the appropriate
+ SFTPError."""
+
+ if not isinstance(res, Failure):
+ logged_res = res
+ if isinstance(res, str): logged_res = "<data of length %r>" % (len(res),)
+ logmsg("SUCCESS %r %r" % (request, logged_res,), level=OPERATIONAL)
+ return res
+
+ err = res
+ logmsg("RAISE %r %r" % (request, err.value), level=OPERATIONAL)
+ try:
+ if noisy: logmsg(traceback.format_exc(err.value), level=NOISY)
+ except Exception: # pragma: no cover
+ pass
+
+ # The message argument to SFTPError must not reveal information that
+ # might compromise anonymity, if we are running over an anonymous network.
+
+ if err.check(SFTPError):
+ # original raiser of SFTPError has responsibility to ensure anonymity
+ raise err
+ if err.check(NoSuchChildError):
+ childname = _utf8(err.value.args[0])
+ raise SFTPError(FX_NO_SUCH_FILE, childname)
+ if err.check(NotWriteableError) or err.check(ChildOfWrongTypeError):
+ msg = _utf8(err.value.args[0])
+ raise SFTPError(FX_PERMISSION_DENIED, msg)
+ if err.check(ExistingChildError):
+ # Versions of SFTP after v3 (which is what twisted.conch implements)
+ # define a specific error code for this case: FX_FILE_ALREADY_EXISTS.
+ # However v3 doesn't; instead, other servers such as sshd return
+ # FX_FAILURE. The gvfs SFTP backend, for example, depends on this
+ # to translate the error to the equivalent of POSIX EEXIST, which is
+ # necessary for some picky programs (such as gedit).
+ msg = _utf8(err.value.args[0])
+ raise SFTPError(FX_FAILURE, msg)
+ if err.check(NotImplementedError):
+ raise SFTPError(FX_OP_UNSUPPORTED, _utf8(err.value))
+ if err.check(EOFError):
+ raise SFTPError(FX_EOF, "end of file reached")
+ if err.check(defer.FirstError):
+ _convert_error(err.value.subFailure, request)
+
+ # We assume that the error message is not anonymity-sensitive.
+ raise SFTPError(FX_FAILURE, _utf8(err.value))
+
+
+def _repr_flags(flags):
+ return "|".join([f for f in
+ [(flags & FXF_READ) and "FXF_READ" or None,
+ (flags & FXF_WRITE) and "FXF_WRITE" or None,
+ (flags & FXF_APPEND) and "FXF_APPEND" or None,
+ (flags & FXF_CREAT) and "FXF_CREAT" or None,
+ (flags & FXF_TRUNC) and "FXF_TRUNC" or None,
+ (flags & FXF_EXCL) and "FXF_EXCL" or None,
+ ]
+ if f])
+
+
+def _lsLine(name, attrs):
+ st_uid = "tahoe"
+ st_gid = "tahoe"
+ st_mtime = attrs.get("mtime", 0)
+ st_mode = attrs["permissions"]
+
+ # Some clients won't tolerate '?' in the size field (#1337).
+ st_size = attrs.get("size", 0)
+
+ # We don't know how many links there really are to this object.
+ st_nlink = 1
+
+ # Based on <https://twistedmatrix.com/trac/browser/trunk/twisted/conch/ls.py?rev=25412>.
+ # We previously could not call the version in Twisted because we needed the change
+ # <https://twistedmatrix.com/trac/changeset/25412> (released in Twisted v8.2).
+ # Since we now depend on Twisted v10.1, consider calling Twisted's version.
+
+ mode = st_mode
+ perms = array.array('c', '-'*10)
+ ft = stat.S_IFMT(mode)
+ if stat.S_ISDIR(ft): perms[0] = 'd'
+ elif stat.S_ISREG(ft): perms[0] = '-'
+ else: perms[0] = '?'
+ # user
+ if mode&stat.S_IRUSR: perms[1] = 'r'
+ if mode&stat.S_IWUSR: perms[2] = 'w'
+ if mode&stat.S_IXUSR: perms[3] = 'x'
+ # group
+ if mode&stat.S_IRGRP: perms[4] = 'r'
+ if mode&stat.S_IWGRP: perms[5] = 'w'
+ if mode&stat.S_IXGRP: perms[6] = 'x'
+ # other
+ if mode&stat.S_IROTH: perms[7] = 'r'
+ if mode&stat.S_IWOTH: perms[8] = 'w'
+ if mode&stat.S_IXOTH: perms[9] = 'x'
+ # suid/sgid never set
+
+ l = perms.tostring()
+ l += str(st_nlink).rjust(5) + ' '
+ un = str(st_uid)
+ l += un.ljust(9)
+ gr = str(st_gid)
+ l += gr.ljust(9)
+ sz = str(st_size)
+ l += sz.rjust(8)
+ l += ' '
+ day = 60 * 60 * 24
+ sixmo = day * 7 * 26
+ now = time()
+ if st_mtime + sixmo < now or st_mtime > now + day:
+ # mtime is more than 6 months ago, or more than one day in the future
+ l += strftime("%b %d %Y ", localtime(st_mtime))
+ else:
+ l += strftime("%b %d %H:%M ", localtime(st_mtime))
+ l += name
+ return l
+
+
+def _no_write(parent_readonly, child, metadata=None):
+ """Whether child should be listed as having read-only permissions in parent."""
+
+ if child.is_unknown():
+ return True
+ elif child.is_mutable():
+ return child.is_readonly()
+ elif parent_readonly or IDirectoryNode.providedBy(child):
+ return True
+ else:
+ return metadata is not None and metadata.get('no-write', False)
+
+
+def _populate_attrs(childnode, metadata, size=None):
+ attrs = {}
+
+ # The permissions must have the S_IFDIR (040000) or S_IFREG (0100000)
+ # bits, otherwise the client may refuse to open a directory.
+ # Also, sshfs run as a non-root user requires files and directories
+ # to be world-readable/writeable.
+ # It is important that we never set the executable bits on files.
+ #
+ # Directories and unknown nodes have no size, and SFTP doesn't
+ # require us to make one up.
+ #
+ # childnode might be None, meaning that the file doesn't exist yet,
+ # but we're going to write it later.
+
+ if childnode and childnode.is_unknown():
+ perms = 0
+ elif childnode and IDirectoryNode.providedBy(childnode):
+ perms = S_IFDIR | 0777
+ else:
+ # For files, omit the size if we don't immediately know it.
+ if childnode and size is None:
+ size = childnode.get_size()
+ if size is not None:
+ _assert(isinstance(size, (int, long)) and not isinstance(size, bool), size=size)
+ attrs['size'] = size
+ perms = S_IFREG | 0666
+
+ if metadata:
+ if metadata.get('no-write', False):
+ perms &= S_IFDIR | S_IFREG | 0555 # clear 'w' bits
+
+ # See webapi.txt for what these times mean.
+ # We would prefer to omit atime, but SFTP version 3 can only
+ # accept mtime if atime is also set.
+ if 'linkmotime' in metadata.get('tahoe', {}):
+ attrs['ctime'] = attrs['mtime'] = attrs['atime'] = _to_sftp_time(metadata['tahoe']['linkmotime'])
+ elif 'mtime' in metadata:
+ attrs['ctime'] = attrs['mtime'] = attrs['atime'] = _to_sftp_time(metadata['mtime'])
+
+ if 'linkcrtime' in metadata.get('tahoe', {}):
+ attrs['createtime'] = _to_sftp_time(metadata['tahoe']['linkcrtime'])
+
+ attrs['permissions'] = perms
+
+ # twisted.conch.ssh.filetransfer only implements SFTP version 3,
+ # which doesn't include SSH_FILEXFER_ATTR_FLAGS.
+
+ return attrs
+
+
+def _attrs_to_metadata(attrs):
+ metadata = {}
+
+ for key in attrs:
+ if key == "mtime" or key == "ctime" or key == "createtime":
+ metadata[key] = long(attrs[key])
+ elif key.startswith("ext_"):
+ metadata[key] = str(attrs[key])
+
+ perms = attrs.get('permissions', stat.S_IWUSR)
+ if not (perms & stat.S_IWUSR):
+ metadata['no-write'] = True
+
+ return metadata
-class MemoryConsumer:
+
+def _direntry_for(filenode_or_parent, childname, filenode=None):
+ precondition(isinstance(childname, (unicode, NoneType)), childname=childname)
+
+ if childname is None:
+ filenode_or_parent = filenode
+
+ if filenode_or_parent:
+ rw_uri = filenode_or_parent.get_write_uri()
+ if rw_uri and childname:
+ return rw_uri + "/" + childname.encode('utf-8')
+ else:
+ return rw_uri
+
+ return None
+
+
+class OverwriteableFileConsumer(PrefixingLogMixin):
implements(IConsumer)
- def __init__(self):
- self.chunks = []
- self.done = False
+ """I act both as a consumer for the download of the original file contents, and as a
+ wrapper for a temporary file that records the downloaded data and any overwrites.
+ I use a priority queue to keep track of which regions of the file have been overwritten
+ but not yet downloaded, so that the download does not clobber overwritten data.
+ I use another priority queue to record milestones at which to make callbacks
+ indicating that a given number of bytes have been downloaded.
+
+ The temporary file reflects the contents of the file that I represent, except that:
+ - regions that have neither been downloaded nor overwritten, if present,
+ contain garbage.
+ - the temporary file may be shorter than the represented file (it is never longer).
+ The latter's current size is stored in self.current_size.
+
+ This abstraction is mostly independent of SFTP. Consider moving it, if it is found
+ useful for other frontends."""
+
+ def __init__(self, download_size, tempfile_maker):
+ PrefixingLogMixin.__init__(self, facility="tahoe.sftp")
+ if noisy: self.log(".__init__(%r, %r)" % (download_size, tempfile_maker), level=NOISY)
+ self.download_size = download_size
+ self.current_size = download_size
+ self.f = tempfile_maker()
+ self.downloaded = 0
+ self.milestones = [] # empty heap of (offset, d)
+ self.overwrites = [] # empty heap of (start, end)
+ self.is_closed = False
+
+ self.done = defer.Deferred()
+ self.done_status = None # None -> not complete, Failure -> download failed, str -> download succeeded
+ self.producer = None
+
+ def get_file(self):
+ return self.f
+
+ def get_current_size(self):
+ return self.current_size
+
+ def set_current_size(self, size):
+ if noisy: self.log(".set_current_size(%r), current_size = %r, downloaded = %r" %
+ (size, self.current_size, self.downloaded), level=NOISY)
+ if size < self.current_size or size < self.downloaded:
+ self.f.truncate(size)
+ if size > self.current_size:
+ self.overwrite(self.current_size, "\x00" * (size - self.current_size))
+ self.current_size = size
+
+ # make the invariant self.download_size <= self.current_size be true again
+ if size < self.download_size:
+ self.download_size = size
+
+ if self.downloaded >= self.download_size:
+ self.download_done("size changed")
+
def registerProducer(self, p, streaming):
+ if noisy: self.log(".registerProducer(%r, streaming=%r)" % (p, streaming), level=NOISY)
+ if self.producer is not None:
+ raise RuntimeError("producer is already registered")
+
+ self.producer = p
if streaming:
# call resumeProducing once to start things off
p.resumeProducing()
else:
- while not self.done:
- p.resumeProducing()
+ def _iterate():
+ if self.done_status is None:
+ p.resumeProducing()
+ eventually(_iterate)
+ _iterate()
+
def write(self, data):
- self.chunks.append(data)
+ if noisy: self.log(".write(<data of length %r>)" % (len(data),), level=NOISY)
+ if self.is_closed:
+ return
+
+ if self.downloaded >= self.download_size:
+ return
+
+ next_downloaded = self.downloaded + len(data)
+ if next_downloaded > self.download_size:
+ data = data[:(self.download_size - self.downloaded)]
+
+ while len(self.overwrites) > 0:
+ (start, end) = self.overwrites[0]
+ if start >= next_downloaded:
+ # This and all remaining overwrites are after the data we just downloaded.
+ break
+ if start > self.downloaded:
+ # The data we just downloaded has been partially overwritten.
+ # Write the prefix of it that precedes the overwritten region.
+ self.f.seek(self.downloaded)
+ self.f.write(data[:(start - self.downloaded)])
+
+ # This merges consecutive overwrites if possible, which allows us to detect the
+ # case where the download can be stopped early because the remaining region
+ # to download has already been fully overwritten.
+ heapq.heappop(self.overwrites)
+ while len(self.overwrites) > 0:
+ (start1, end1) = self.overwrites[0]
+ if start1 > end:
+ break
+ end = end1
+ heapq.heappop(self.overwrites)
+
+ if end >= next_downloaded:
+ # This overwrite extends past the downloaded data, so there is no
+ # more data to consider on this call.
+ heapq.heappush(self.overwrites, (next_downloaded, end))
+ self._update_downloaded(next_downloaded)
+ return
+ elif end >= self.downloaded:
+ data = data[(end - self.downloaded):]
+ self._update_downloaded(end)
+
+ self.f.seek(self.downloaded)
+ self.f.write(data)
+ self._update_downloaded(next_downloaded)
+
+ def _update_downloaded(self, new_downloaded):
+ self.downloaded = new_downloaded
+ milestone = new_downloaded
+ if len(self.overwrites) > 0:
+ (start, end) = self.overwrites[0]
+ if start <= new_downloaded and end > milestone:
+ milestone = end
+
+ while len(self.milestones) > 0:
+ (next, d) = self.milestones[0]
+ if next > milestone:
+ return
+ if noisy: self.log("MILESTONE %r %r" % (next, d), level=NOISY)
+ heapq.heappop(self.milestones)
+ eventually_callback(d)("reached")
+
+ if milestone >= self.download_size:
+ self.download_done("reached download size")
+
+ def overwrite(self, offset, data):
+ if noisy: self.log(".overwrite(%r, <data of length %r>)" % (offset, len(data)), level=NOISY)
+ if self.is_closed:
+ self.log("overwrite called on a closed OverwriteableFileConsumer", level=WEIRD)
+ raise SFTPError(FX_BAD_MESSAGE, "cannot write to a closed file handle")
+
+ if offset > self.current_size:
+ # Normally writing at an offset beyond the current end-of-file
+ # would leave a hole that appears filled with zeroes. However, an
+ # EncryptedTemporaryFile doesn't behave like that (if there is a
+ # hole in the file on disk, the zeroes that are read back will be
+ # XORed with the keystream). So we must explicitly write zeroes in
+ # the gap between the current EOF and the offset.
+
+ self.f.seek(self.current_size)
+ self.f.write("\x00" * (offset - self.current_size))
+ start = self.current_size
+ else:
+ self.f.seek(offset)
+ start = offset
+
+ self.f.write(data)
+ end = offset + len(data)
+ self.current_size = max(self.current_size, end)
+ if end > self.downloaded:
+ heapq.heappush(self.overwrites, (start, end))
+
+ def read(self, offset, length):
+ """When the data has been read, callback the Deferred that we return with this data.
+ Otherwise errback the Deferred that we return.
+ The caller must perform no more overwrites until the Deferred has fired."""
+
+ if noisy: self.log(".read(%r, %r), current_size = %r" % (offset, length, self.current_size), level=NOISY)
+ if self.is_closed:
+ self.log("read called on a closed OverwriteableFileConsumer", level=WEIRD)
+ raise SFTPError(FX_BAD_MESSAGE, "cannot read from a closed file handle")
+
+ # Note that the overwrite method is synchronous. When a write request is processed
+ # (e.g. a writeChunk request on the async queue of GeneralSFTPFile), overwrite will
+ # be called and will update self.current_size if necessary before returning. Therefore,
+ # self.current_size will be up-to-date for a subsequent call to this read method, and
+ # so it is correct to do the check for a read past the end-of-file here.
+ if offset >= self.current_size:
+ def _eof(): raise EOFError("read past end of file")
+ return defer.execute(_eof)
+
+ if offset + length > self.current_size:
+ length = self.current_size - offset
+ if noisy: self.log("truncating read to %r bytes" % (length,), level=NOISY)
+
+ needed = min(offset + length, self.download_size)
+
+ # If we fail to reach the needed number of bytes, the read request will fail.
+ d = self.when_reached_or_failed(needed)
+ def _reached_in_read(res):
+ # It is not necessarily the case that self.downloaded >= needed, because
+ # the file might have been truncated (thus truncating the download) and
+ # then extended.
+
+ _assert(self.current_size >= offset + length,
+ current_size=self.current_size, offset=offset, length=length)
+ if noisy: self.log("_reached_in_read(%r), self.f = %r" % (res, self.f,), level=NOISY)
+ self.f.seek(offset)
+ return self.f.read(length)
+ d.addCallback(_reached_in_read)
+ return d
+
+ def when_reached_or_failed(self, index):
+ if noisy: self.log(".when_reached_or_failed(%r)" % (index,), level=NOISY)
+ def _reached(res):
+ if noisy: self.log("reached %r with result %r" % (index, res), level=NOISY)
+ return res
+
+ if self.done_status is not None:
+ return defer.execute(_reached, self.done_status)
+ if index <= self.downloaded: # already reached successfully
+ if noisy: self.log("already reached %r successfully" % (index,), level=NOISY)
+ return defer.succeed("already reached successfully")
+ d = defer.Deferred()
+ d.addCallback(_reached)
+ heapq.heappush(self.milestones, (index, d))
+ return d
+
+ def when_done(self):
+ d = defer.Deferred()
+ self.done.addCallback(lambda ign: eventually_callback(d)(self.done_status))
+ return d
+
+ def download_done(self, res):
+ _assert(isinstance(res, (str, Failure)), res=res)
+ # Only the first call to download_done counts, but we log subsequent calls
+ # (multiple calls are normal).
+ if self.done_status is not None:
+ self.log("IGNORING extra call to download_done with result %r; previous result was %r"
+ % (res, self.done_status), level=OPERATIONAL)
+ return
+
+ self.log("DONE with result %r" % (res,), level=OPERATIONAL)
+
+ # We avoid errbacking self.done so that we are not left with an 'Unhandled error in Deferred'
+ # in case when_done() is never called. Instead we stash the failure in self.done_status,
+ # from where the callback added in when_done() can retrieve it.
+ self.done_status = res
+ eventually_callback(self.done)(None)
+
+ while len(self.milestones) > 0:
+ (next, d) = self.milestones[0]
+ if noisy: self.log("MILESTONE FINISH %r %r %r" % (next, d, res), level=NOISY)
+ heapq.heappop(self.milestones)
+ # The callback means that the milestone has been reached if
+ # it is ever going to be. Note that the file may have been
+ # truncated to before the milestone.
+ eventually_callback(d)(res)
+
+ def close(self):
+ if not self.is_closed:
+ self.is_closed = True
+ try:
+ self.f.close()
+ except Exception, e:
+ self.log("suppressed %r from close of temporary file %r" % (e, self.f), level=WEIRD)
+ self.download_done("closed")
+ return self.done_status
+
def unregisterProducer(self):
- self.done = True
+ # This will happen just before our client calls download_done, which will tell
+ # us the outcome of the download; we don't know the outcome at this point.
+ self.producer = None
+ self.log("producer unregistered", level=NOISY)
+
+
+SIZE_THRESHOLD = 1000
-def download_to_data(n, offset=0, size=None):
- d = n.read(MemoryConsumer(), offset, size)
- d.addCallback(lambda mc: "".join(mc.chunks))
- return d
-class ReadFile:
+class ShortReadOnlySFTPFile(PrefixingLogMixin):
implements(ISFTPFile)
- def __init__(self, node):
- self.node = node
+ """I represent a file handle to a particular file on an SFTP connection.
+ I am used only for short immutable files opened in read-only mode.
+ When I am created, the file contents start to be downloaded to memory.
+ self.async is used to delay read requests until the download has finished."""
+
+ def __init__(self, userpath, filenode, metadata):
+ PrefixingLogMixin.__init__(self, facility="tahoe.sftp", prefix=userpath)
+ if noisy: self.log(".__init__(%r, %r, %r)" % (userpath, filenode, metadata), level=NOISY)
+
+ precondition(isinstance(userpath, str) and IFileNode.providedBy(filenode),
+ userpath=userpath, filenode=filenode)
+ self.filenode = filenode
+ self.metadata = metadata
+ self.async = download_to_data(filenode)
+ self.closed = False
+
def readChunk(self, offset, length):
- d = download_to_data(self.node, offset, length)
- def _got(data):
+ request = ".readChunk(%r, %r)" % (offset, length)
+ self.log(request, level=OPERATIONAL)
+
+ if self.closed:
+ def _closed(): raise SFTPError(FX_BAD_MESSAGE, "cannot read from a closed file handle")
+ return defer.execute(_closed)
+
+ d = defer.Deferred()
+ def _read(data):
+ if noisy: self.log("_read(<data of length %r>) in readChunk(%r, %r)" % (len(data), offset, length), level=NOISY)
+
+ # "In response to this request, the server will read as many bytes as it
+ # can from the file (up to 'len'), and return them in a SSH_FXP_DATA
+ # message. If an error occurs or EOF is encountered before reading any
+ # data, the server will respond with SSH_FXP_STATUS. For normal disk
+ # files, it is guaranteed that this will read the specified number of
+ # bytes, or up to end of file."
+ #
+ # i.e. we respond with an EOF error iff offset is already at EOF.
+
+ if offset >= len(data):
+ eventually_errback(d)(Failure(SFTPError(FX_EOF, "read at or past end of file")))
+ else:
+ eventually_callback(d)(data[offset:offset+length]) # truncated if offset+length > len(data)
return data
- d.addCallback(_got)
+ self.async.addCallbacks(_read, eventually_errback(d))
+ d.addBoth(_convert_error, request)
return d
+
+ def writeChunk(self, offset, data):
+ self.log(".writeChunk(%r, <data of length %r>) denied" % (offset, len(data)), level=OPERATIONAL)
+
+ def _denied(): raise SFTPError(FX_PERMISSION_DENIED, "file handle was not opened for writing")
+ return defer.execute(_denied)
+
def close(self):
- pass
+ self.log(".close()", level=OPERATIONAL)
+
+ self.closed = True
+ return defer.succeed(None)
+
def getAttrs(self):
- print "GETATTRS(file)"
- raise NotImplementedError
+ request = ".getAttrs()"
+ self.log(request, level=OPERATIONAL)
+
+ if self.closed:
+ def _closed(): raise SFTPError(FX_BAD_MESSAGE, "cannot get attributes for a closed file handle")
+ return defer.execute(_closed)
+
+ d = defer.execute(_populate_attrs, self.filenode, self.metadata)
+ d.addBoth(_convert_error, request)
+ return d
+
def setAttrs(self, attrs):
- print "SETATTRS(file)", attrs
- raise NotImplementedError
+ self.log(".setAttrs(%r) denied" % (attrs,), level=OPERATIONAL)
+ def _denied(): raise SFTPError(FX_PERMISSION_DENIED, "file handle was not opened for writing")
+ return defer.execute(_denied)
+
-class WriteFile:
+class GeneralSFTPFile(PrefixingLogMixin):
implements(ISFTPFile)
+ """I represent a file handle to a particular file on an SFTP connection.
+ I wrap an instance of OverwriteableFileConsumer, which is responsible for
+ storing the file contents. In order to allow write requests to be satisfied
+ immediately, there is effectively a FIFO queue between requests made to this
+ file handle, and requests to my OverwriteableFileConsumer. This queue is
+ implemented by the callback chain of self.async.
+
+ When first constructed, I am in an 'unopened' state that causes most
+ operations to be delayed until 'open' is called."""
+
+ def __init__(self, userpath, flags, close_notify, convergence):
+ PrefixingLogMixin.__init__(self, facility="tahoe.sftp", prefix=userpath)
+ if noisy: self.log(".__init__(%r, %r = %r, %r, <convergence censored>)" %
+ (userpath, flags, _repr_flags(flags), close_notify), level=NOISY)
- def __init__(self, parent, childname, convergence):
- self.parent = parent
- self.childname = childname
+ precondition(isinstance(userpath, str), userpath=userpath)
+ self.userpath = userpath
+ self.flags = flags
+ self.close_notify = close_notify
self.convergence = convergence
- self.f = tempfile.TemporaryFile()
+ self.async = defer.Deferred()
+ # Creating or truncating the file is a change, but if FXF_EXCL is set, a zero-length file has already been created.
+ self.has_changed = (flags & (FXF_CREAT | FXF_TRUNC)) and not (flags & FXF_EXCL)
+ self.closed = False
+ self.abandoned = False
+ self.parent = None
+ self.childname = None
+ self.filenode = None
+ self.metadata = None
+
+ # self.consumer should only be relied on in callbacks for self.async, since it might
+ # not be set before then.
+ self.consumer = None
+
+ def open(self, parent=None, childname=None, filenode=None, metadata=None):
+ self.log(".open(parent=%r, childname=%r, filenode=%r, metadata=%r)" %
+ (parent, childname, filenode, metadata), level=OPERATIONAL)
+
+ precondition(isinstance(childname, (unicode, NoneType)), childname=childname)
+ precondition(filenode is None or IFileNode.providedBy(filenode), filenode=filenode)
+ precondition(not self.closed, sftpfile=self)
+
+ # If the file has been renamed, the new (parent, childname) takes precedence.
+ if self.parent is None:
+ self.parent = parent
+ if self.childname is None:
+ self.childname = childname
+ self.filenode = filenode
+ self.metadata = metadata
+
+ tempfile_maker = EncryptedTemporaryFile
+
+ if (self.flags & FXF_TRUNC) or not filenode:
+ # We're either truncating or creating the file, so we don't need the old contents.
+ self.consumer = OverwriteableFileConsumer(0, tempfile_maker)
+ self.consumer.download_done("download not needed")
+ else:
+ self.async.addCallback(lambda ignored: filenode.get_best_readable_version())
+
+ def _read(version):
+ if noisy: self.log("_read", level=NOISY)
+ download_size = version.get_size()
+ _assert(download_size is not None)
+
+ self.consumer = OverwriteableFileConsumer(download_size, tempfile_maker)
+
+ d = version.read(self.consumer, 0, None)
+ def _finished(res):
+ if not isinstance(res, Failure):
+ res = "download finished"
+ self.consumer.download_done(res)
+ d.addBoth(_finished)
+ # It is correct to drop d here.
+ self.async.addCallback(_read)
+
+ eventually_callback(self.async)(None)
+
+ if noisy: self.log("open done", level=NOISY)
+ return self
+
+ def get_userpath(self):
+ return self.userpath
+
+ def get_direntry(self):
+ return _direntry_for(self.parent, self.childname)
+
+ def rename(self, new_userpath, new_parent, new_childname):
+ self.log(".rename(%r, %r, %r)" % (new_userpath, new_parent, new_childname), level=OPERATIONAL)
+
+ precondition(isinstance(new_userpath, str) and isinstance(new_childname, unicode),
+ new_userpath=new_userpath, new_childname=new_childname)
+ self.userpath = new_userpath
+ self.parent = new_parent
+ self.childname = new_childname
+
+ def abandon(self):
+ self.log(".abandon()", level=OPERATIONAL)
+
+ self.abandoned = True
+
+ def sync(self, ign=None):
+ # The ign argument allows some_file.sync to be used as a callback.
+ self.log(".sync()", level=OPERATIONAL)
+
+ d = defer.Deferred()
+ self.async.addBoth(eventually_callback(d))
+ def _done(res):
+ if noisy: self.log("_done(%r) in .sync()" % (res,), level=NOISY)
+ return res
+ d.addBoth(_done)
+ return d
+
+ def readChunk(self, offset, length):
+ request = ".readChunk(%r, %r)" % (offset, length)
+ self.log(request, level=OPERATIONAL)
+
+ if not (self.flags & FXF_READ):
+ def _denied(): raise SFTPError(FX_PERMISSION_DENIED, "file handle was not opened for reading")
+ return defer.execute(_denied)
+
+ if self.closed:
+ def _closed(): raise SFTPError(FX_BAD_MESSAGE, "cannot read from a closed file handle")
+ return defer.execute(_closed)
+
+ d = defer.Deferred()
+ def _read(ign):
+ if noisy: self.log("_read in readChunk(%r, %r)" % (offset, length), level=NOISY)
+ d2 = self.consumer.read(offset, length)
+ d2.addBoth(eventually_callback(d))
+ # It is correct to drop d2 here.
+ return None
+ self.async.addCallbacks(_read, eventually_errback(d))
+ d.addBoth(_convert_error, request)
+ return d
+
def writeChunk(self, offset, data):
- self.f.seek(offset)
- self.f.write(data)
+ self.log(".writeChunk(%r, <data of length %r>)" % (offset, len(data)), level=OPERATIONAL)
+
+ if not (self.flags & FXF_WRITE):
+ def _denied(): raise SFTPError(FX_PERMISSION_DENIED, "file handle was not opened for writing")
+ return defer.execute(_denied)
+
+ if self.closed:
+ def _closed(): raise SFTPError(FX_BAD_MESSAGE, "cannot write to a closed file handle")
+ return defer.execute(_closed)
+
+ self.has_changed = True
+
+ # Note that we return without waiting for the write to occur. Reads and
+ # close wait for prior writes, and will fail if any prior operation failed.
+ # This is ok because SFTP makes no guarantee that the write completes
+ # before the request does. In fact it explicitly allows write errors to be
+ # delayed until close:
+ # "One should note that on some server platforms even a close can fail.
+ # This can happen e.g. if the server operating system caches writes,
+ # and an error occurs while flushing cached writes during the close."
+
+ def _write(ign):
+ if noisy: self.log("_write in .writeChunk(%r, <data of length %r>), current_size = %r" %
+ (offset, len(data), self.consumer.get_current_size()), level=NOISY)
+ # FXF_APPEND means that we should always write at the current end of file.
+ write_offset = offset
+ if self.flags & FXF_APPEND:
+ write_offset = self.consumer.get_current_size()
+
+ self.consumer.overwrite(write_offset, data)
+ if noisy: self.log("overwrite done", level=NOISY)
+ return None
+ self.async.addCallback(_write)
+ # don't addErrback to self.async, just allow subsequent async ops to fail.
+ return defer.succeed(None)
+
+ def _do_close(self, res, d=None):
+ if noisy: self.log("_do_close(%r)" % (res,), level=NOISY)
+ status = None
+ if self.consumer:
+ status = self.consumer.close()
+
+ # We must close_notify before re-firing self.async.
+ if self.close_notify:
+ self.close_notify(self.userpath, self.parent, self.childname, self)
+
+ if not isinstance(res, Failure) and isinstance(status, Failure):
+ res = status
+
+ if d:
+ eventually_callback(d)(res)
+ elif isinstance(res, Failure):
+ self.log("suppressing %r" % (res,), level=OPERATIONAL)
def close(self):
- u = FileHandle(self.f, self.convergence)
- d = self.parent.add_file(self.childname, u)
+ request = ".close()"
+ self.log(request, level=OPERATIONAL)
+
+ if self.closed:
+ return defer.succeed(None)
+
+ # This means that close has been called, not that the close has succeeded.
+ self.closed = True
+
+ if not (self.flags & (FXF_WRITE | FXF_CREAT)):
+ # We never fail a close of a handle opened only for reading, even if the file
+ # failed to download. (We could not do so deterministically, because it would
+ # depend on whether we reached the point of failure before abandoning the
+ # download.) Any reads that depended on file content that could not be downloaded
+ # will have failed. It is important that we don't close the consumer until
+ # previous read operations have completed.
+ self.async.addBoth(self._do_close)
+ return defer.succeed(None)
+
+ # We must capture the abandoned, parent, and childname variables synchronously
+ # at the close call. This is needed by the correctness arguments in the comments
+ # for _abandon_any_heisenfiles and _rename_heisenfiles.
+ # Note that the file must have been opened before it can be closed.
+ abandoned = self.abandoned
+ parent = self.parent
+ childname = self.childname
+
+ # has_changed is set when writeChunk is called, not when the write occurs, so
+ # it is correct to optimize out the commit if it is False at the close call.
+ has_changed = self.has_changed
+
+ def _commit(ign):
+ d2 = self.consumer.when_done()
+ if self.filenode and self.filenode.is_mutable():
+ self.log("update mutable file %r childname=%r metadata=%r"
+ % (self.filenode, childname, self.metadata), level=OPERATIONAL)
+ if self.metadata.get('no-write', False) and not self.filenode.is_readonly():
+ _assert(parent and childname, parent=parent, childname=childname, metadata=self.metadata)
+ d2.addCallback(lambda ign: parent.set_metadata_for(childname, self.metadata))
+
+ d2.addCallback(lambda ign: self.filenode.overwrite(MutableFileHandle(self.consumer.get_file())))
+ else:
+ def _add_file(ign):
+ self.log("_add_file childname=%r" % (childname,), level=OPERATIONAL)
+ u = FileHandle(self.consumer.get_file(), self.convergence)
+ return parent.add_file(childname, u, metadata=self.metadata)
+ d2.addCallback(_add_file)
+ return d2
+
+ # If the file has been abandoned, we don't want the close operation to get "stuck",
+ # even if self.async fails to re-fire. Completing the close independently of self.async
+ # in that case should ensure that dropping an ssh connection is sufficient to abandon
+ # any heisenfiles that were not explicitly closed in that connection.
+ if abandoned or not has_changed:
+ d = defer.succeed(None)
+ self.async.addBoth(self._do_close)
+ else:
+ d = defer.Deferred()
+ self.async.addCallback(_commit)
+ self.async.addBoth(self._do_close, d)
+ d.addBoth(_convert_error, request)
return d
def getAttrs(self):
- print "GETATTRS(file)"
- raise NotImplementedError
- def setAttrs(self, attrs):
- print "SETATTRS(file)", attrs
- raise NotImplementedError
+ request = ".getAttrs()"
+ self.log(request, level=OPERATIONAL)
+ if self.closed:
+ def _closed(): raise SFTPError(FX_BAD_MESSAGE, "cannot get attributes for a closed file handle")
+ return defer.execute(_closed)
-class NoParentError(Exception):
- pass
+ # Optimization for read-only handles, when we already know the metadata.
+ if not (self.flags & (FXF_WRITE | FXF_CREAT)) and self.metadata and self.filenode and not self.filenode.is_mutable():
+ return defer.succeed(_populate_attrs(self.filenode, self.metadata))
-class PermissionError(Exception):
- pass
+ d = defer.Deferred()
+ def _get(ign):
+ if noisy: self.log("_get(%r) in %r, filenode = %r, metadata = %r" % (ign, request, self.filenode, self.metadata), level=NOISY)
-from twisted.conch.ssh.filetransfer import FileTransferServer, SFTPError, \
- FX_NO_SUCH_FILE, FX_FILE_ALREADY_EXISTS, FX_OP_UNSUPPORTED, \
- FX_PERMISSION_DENIED
-from twisted.conch.ssh.filetransfer import FXF_READ, FXF_WRITE, FXF_APPEND, FXF_CREAT, FXF_TRUNC, FXF_EXCL
+ # self.filenode might be None, but that's ok.
+ attrs = _populate_attrs(self.filenode, self.metadata, size=self.consumer.get_current_size())
+ eventually_callback(d)(attrs)
+ return None
+ self.async.addCallbacks(_get, eventually_errback(d))
+ d.addBoth(_convert_error, request)
+ return d
-class SFTPUser(ConchUser):
- def __init__(self, client, rootnode, username, convergence):
- ConchUser.__init__(self)
- self.channelLookup["session"] = session.SSHSession
- self.subsystemLookup["sftp"] = FileTransferServer
+ def setAttrs(self, attrs, only_if_at=None):
+ request = ".setAttrs(%r, only_if_at=%r)" % (attrs, only_if_at)
+ self.log(request, level=OPERATIONAL)
+
+ if not (self.flags & FXF_WRITE):
+ def _denied(): raise SFTPError(FX_PERMISSION_DENIED, "file handle was not opened for writing")
+ return defer.execute(_denied)
+
+ if self.closed:
+ def _closed(): raise SFTPError(FX_BAD_MESSAGE, "cannot set attributes for a closed file handle")
+ return defer.execute(_closed)
+
+ size = attrs.get("size", None)
+ if size is not None and (not isinstance(size, (int, long)) or size < 0):
+ def _bad(): raise SFTPError(FX_BAD_MESSAGE, "new size is not a valid nonnegative integer")
+ return defer.execute(_bad)
+
+ d = defer.Deferred()
+ def _set(ign):
+ if noisy: self.log("_set(%r) in %r" % (ign, request), level=NOISY)
+ current_direntry = _direntry_for(self.parent, self.childname, self.filenode)
+ if only_if_at and only_if_at != current_direntry:
+ if noisy: self.log("not setting attributes: current_direntry=%r in %r" %
+ (current_direntry, request), level=NOISY)
+ return None
+
+ now = time()
+ self.metadata = update_metadata(self.metadata, _attrs_to_metadata(attrs), now)
+ if size is not None:
+ # TODO: should we refuse to truncate a file opened with FXF_APPEND?
+ # <http://allmydata.org/trac/tahoe-lafs/ticket/1037#comment:20>
+ self.consumer.set_current_size(size)
+ eventually_callback(d)(None)
+ return None
+ self.async.addCallbacks(_set, eventually_errback(d))
+ d.addBoth(_convert_error, request)
+ return d
- self.client = client
- self.root = rootnode
- self.username = username
- self.convergence = convergence
class StoppableList:
def __init__(self, items):
def close(self):
pass
-class FakeStat:
- pass
-class BadRemoveRequest(Exception):
- pass
+class Reason:
+ def __init__(self, value):
+ self.value = value
+
-class SFTPHandler:
+# A "heisenfile" is a file that has been opened with write flags
+# (FXF_WRITE and/or FXF_CREAT) and not yet close-notified.
+# 'all_heisenfiles' maps from a direntry string to a list of
+# GeneralSFTPFile.
+#
+# A direntry string is parent_write_uri + "/" + childname_utf8 for
+# an immutable file, or file_write_uri for a mutable file.
+# Updates to this dict are single-threaded.
+
+all_heisenfiles = {}
+
+def _reload():
+ global all_heisenfiles
+ all_heisenfiles = {}
+
+class SFTPUserHandler(ConchUser, PrefixingLogMixin):
implements(ISFTPServer)
- def __init__(self, user):
- print "Creating SFTPHandler from", user
- self.client = user.client
- self.root = user.root
- self.username = user.username
- self.convergence = user.convergence
+ def __init__(self, client, rootnode, username):
+ ConchUser.__init__(self)
+ PrefixingLogMixin.__init__(self, facility="tahoe.sftp", prefix=username)
+ if noisy: self.log(".__init__(%r, %r, %r)" % (client, rootnode, username), level=NOISY)
+
+ self.channelLookup["session"] = session.SSHSession
+ self.subsystemLookup["sftp"] = FileTransferServer
+
+ self._client = client
+ self._root = rootnode
+ self._username = username
+ self._convergence = client.convergence
+
+ # maps from UTF-8 paths for this user, to files written and still open
+ self._heisenfiles = {}
def gotVersion(self, otherVersion, extData):
- return {}
-
- def openFile(self, filename, flags, attrs):
- f = "|".join([f for f in
- [(flags & FXF_READ) and "FXF_READ" or None,
- (flags & FXF_WRITE) and "FXF_WRITE" or None,
- (flags & FXF_APPEND) and "FXF_APPEND" or None,
- (flags & FXF_CREAT) and "FXF_CREAT" or None,
- (flags & FXF_TRUNC) and "FXF_TRUNC" or None,
- (flags & FXF_EXCL) and "FXF_EXCL" or None,
- ]
- if f])
- print "OPENFILE", filename, flags, f, attrs
- # this is used for both reading and writing.
-
-# createPlease = False
-# exclusive = False
-# openFlags = 0
-#
-# if flags & FXF_READ == FXF_READ and flags & FXF_WRITE == 0:
-# openFlags = os.O_RDONLY
-# if flags & FXF_WRITE == FXF_WRITE and flags & FXF_READ == 0:
-# createPlease = True
-# openFlags = os.O_WRONLY
-# if flags & FXF_WRITE == FXF_WRITE and flags & FXF_READ == FXF_READ:
-# createPlease = True
-# openFlags = os.O_RDWR
-# if flags & FXF_APPEND == FXF_APPEND:
-# createPlease = True
-# openFlags |= os.O_APPEND
-# if flags & FXF_CREAT == FXF_CREAT:
-# createPlease = True
-# openFlags |= os.O_CREAT
-# if flags & FXF_TRUNC == FXF_TRUNC:
-# openFlags |= os.O_TRUNC
-# if flags & FXF_EXCL == FXF_EXCL:
-# exclusive = True
-
- # /usr/bin/sftp 'get' gives us FXF_READ, while 'put' on a new file
- # gives FXF_WRITE,FXF_CREAT,FXF_TRUNC . I'm guessing that 'put' on an
- # existing file gives the same.
-
- path = self._convert_sftp_path(filename)
-
- if flags & FXF_READ:
- if flags & FXF_WRITE:
- raise NotImplementedError
- d = self._get_node_and_metadata_for_path(path)
- d.addCallback(lambda (node,metadata): ReadFile(node))
- d.addErrback(self._convert_error)
- return d
+ self.log(".gotVersion(%r, %r)" % (otherVersion, extData), level=OPERATIONAL)
+
+ # advertise the same extensions as the OpenSSH SFTP server
+ # <http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL?rev=1.15>
+ return {'posix-rename@openssh.com': '1',
+ 'statvfs@openssh.com': '2',
+ 'fstatvfs@openssh.com': '2',
+ }
+
+ def logout(self):
+ self.log(".logout()", level=OPERATIONAL)
+
+ for files in self._heisenfiles.itervalues():
+ for f in files:
+ f.abandon()
+
+ def _add_heisenfile_by_path(self, file):
+ self.log("._add_heisenfile_by_path(%r)" % (file,), level=OPERATIONAL)
+
+ userpath = file.get_userpath()
+ if userpath in self._heisenfiles:
+ self._heisenfiles[userpath] += [file]
+ else:
+ self._heisenfiles[userpath] = [file]
+
+ def _add_heisenfile_by_direntry(self, file):
+ self.log("._add_heisenfile_by_direntry(%r)" % (file,), level=OPERATIONAL)
+
+ direntry = file.get_direntry()
+ if direntry:
+ if direntry in all_heisenfiles:
+ all_heisenfiles[direntry] += [file]
+ else:
+ all_heisenfiles[direntry] = [file]
+
+ def _abandon_any_heisenfiles(self, userpath, direntry):
+ request = "._abandon_any_heisenfiles(%r, %r)" % (userpath, direntry)
+ self.log(request, level=OPERATIONAL)
+
+ precondition(isinstance(userpath, str), userpath=userpath)
+
+ # First we synchronously mark all heisenfiles matching the userpath or direntry
+ # as abandoned, and remove them from the two heisenfile dicts. Then we .sync()
+ # each file that we abandoned.
+ #
+ # For each file, the call to .abandon() occurs:
+ # * before the file is closed, in which case it will never be committed
+ # (uploaded+linked or published); or
+ # * after it is closed but before it has been close_notified, in which case the
+ # .sync() ensures that it has been committed (successfully or not) before we
+ # return.
+ #
+ # This avoids a race that might otherwise cause the file to be committed after
+ # the remove operation has completed.
+ #
+ # We return a Deferred that fires with True if any files were abandoned (this
+ # does not mean that they were not committed; it is used to determine whether
+ # a NoSuchChildError from the attempt to delete the file should be suppressed).
+
+ files = []
+ if direntry in all_heisenfiles:
+ files = all_heisenfiles[direntry]
+ del all_heisenfiles[direntry]
+ if userpath in self._heisenfiles:
+ files += self._heisenfiles[userpath]
+ del self._heisenfiles[userpath]
+
+ if noisy: self.log("files = %r in %r" % (files, request), level=NOISY)
+
+ for f in files:
+ f.abandon()
+
+ d = defer.succeed(None)
+ for f in files:
+ d.addBoth(f.sync)
+
+ def _done(ign):
+ self.log("done %r" % (request,), level=OPERATIONAL)
+ return len(files) > 0
+ d.addBoth(_done)
+ return d
+
+ def _rename_heisenfiles(self, from_userpath, from_parent, from_childname,
+ to_userpath, to_parent, to_childname, overwrite=True):
+ request = ("._rename_heisenfiles(%r, %r, %r, %r, %r, %r, overwrite=%r)" %
+ (from_userpath, from_parent, from_childname, to_userpath, to_parent, to_childname, overwrite))
+ self.log(request, level=OPERATIONAL)
+
+ precondition((isinstance(from_userpath, str) and isinstance(from_childname, unicode) and
+ isinstance(to_userpath, str) and isinstance(to_childname, unicode)),
+ from_userpath=from_userpath, from_childname=from_childname, to_userpath=to_userpath, to_childname=to_childname)
+
+ if noisy: self.log("all_heisenfiles = %r\nself._heisenfiles = %r" % (all_heisenfiles, self._heisenfiles), level=NOISY)
+
+ # First we synchronously rename all heisenfiles matching the userpath or direntry.
+ # Then we .sync() each file that we renamed.
+ #
+ # For each file, the call to .rename occurs:
+ # * before the file is closed, in which case it will be committed at the
+ # new direntry; or
+ # * after it is closed but before it has been close_notified, in which case the
+ # .sync() ensures that it has been committed (successfully or not) before we
+ # return.
+ #
+ # This avoids a race that might otherwise cause the file to be committed at the
+ # old name after the rename operation has completed.
+ #
+ # Note that if overwrite is False, the caller should already have checked
+ # whether a real direntry exists at the destination. It is possible that another
+ # direntry (heisen or real) comes to exist at the destination after that check,
+ # but in that case it is correct for the rename to succeed (and for the commit
+ # of the heisenfile at the destination to possibly clobber the other entry, since
+ # that can happen anyway when we have concurrent write handles to the same direntry).
+ #
+ # We return a Deferred that fires with True if any files were renamed (this
+ # does not mean that they were not committed; it is used to determine whether
+ # a NoSuchChildError from the rename attempt should be suppressed). If overwrite
+ # is False and there were already heisenfiles at the destination userpath or
+ # direntry, we return a Deferred that fails with SFTPError(FX_PERMISSION_DENIED).
+
+ from_direntry = _direntry_for(from_parent, from_childname)
+ to_direntry = _direntry_for(to_parent, to_childname)
+
+ if noisy: self.log("from_direntry = %r, to_direntry = %r, len(all_heisenfiles) = %r, len(self._heisenfiles) = %r in %r" %
+ (from_direntry, to_direntry, len(all_heisenfiles), len(self._heisenfiles), request), level=NOISY)
+
+ if not overwrite and (to_userpath in self._heisenfiles or to_direntry in all_heisenfiles):
+ def _existing(): raise SFTPError(FX_PERMISSION_DENIED, "cannot rename to existing path " + to_userpath)
+ if noisy: self.log("existing", level=NOISY)
+ return defer.execute(_existing)
+
+ from_files = []
+ if from_direntry in all_heisenfiles:
+ from_files = all_heisenfiles[from_direntry]
+ del all_heisenfiles[from_direntry]
+ if from_userpath in self._heisenfiles:
+ from_files += self._heisenfiles[from_userpath]
+ del self._heisenfiles[from_userpath]
+
+ if noisy: self.log("from_files = %r in %r" % (from_files, request), level=NOISY)
+
+ for f in from_files:
+ f.rename(to_userpath, to_parent, to_childname)
+ self._add_heisenfile_by_path(f)
+ self._add_heisenfile_by_direntry(f)
+
+ d = defer.succeed(None)
+ for f in from_files:
+ d.addBoth(f.sync)
+
+ def _done(ign):
+ if noisy: self.log("done: len(all_heisenfiles) = %r, len(self._heisenfiles) = %r in %r" %
+ (len(all_heisenfiles), len(self._heisenfiles), request), level=NOISY)
+ return len(from_files) > 0
+ d.addBoth(_done)
+ return d
+
+ def _update_attrs_for_heisenfiles(self, userpath, direntry, attrs):
+ request = "._update_attrs_for_heisenfiles(%r, %r, %r)" % (userpath, direntry, attrs)
+ self.log(request, level=OPERATIONAL)
+
+ _assert(isinstance(userpath, str) and isinstance(direntry, str),
+ userpath=userpath, direntry=direntry)
+
+ files = []
+ if direntry in all_heisenfiles:
+ files = all_heisenfiles[direntry]
+ if userpath in self._heisenfiles:
+ files += self._heisenfiles[userpath]
+
+ if noisy: self.log("files = %r in %r" % (files, request), level=NOISY)
+
+ # We set the metadata for all heisenfiles at this path or direntry.
+ # Since a direntry includes a write URI, we must have authority to
+ # change the metadata of heisenfiles found in the all_heisenfiles dict.
+ # However that's not necessarily the case for heisenfiles found by
+ # path. Therefore we tell the setAttrs method of each file to only
+ # perform the update if the file is at the correct direntry.
+
+ d = defer.succeed(None)
+ for f in files:
+ d.addBoth(f.setAttrs, attrs, only_if_at=direntry)
+
+ def _done(ign):
+ self.log("done %r" % (request,), level=OPERATIONAL)
+ # TODO: this should not return True if only_if_at caused all files to be skipped.
+ return len(files) > 0
+ d.addBoth(_done)
+ return d
+
+ def _sync_heisenfiles(self, userpath, direntry, ignore=None):
+ request = "._sync_heisenfiles(%r, %r, ignore=%r)" % (userpath, direntry, ignore)
+ self.log(request, level=OPERATIONAL)
+
+ _assert(isinstance(userpath, str) and isinstance(direntry, (str, NoneType)),
+ userpath=userpath, direntry=direntry)
+
+ files = []
+ if direntry in all_heisenfiles:
+ files = all_heisenfiles[direntry]
+ if userpath in self._heisenfiles:
+ files += self._heisenfiles[userpath]
+
+ if noisy: self.log("files = %r in %r" % (files, request), level=NOISY)
- if flags & FXF_WRITE:
- if not (flags & FXF_CREAT) or not (flags & FXF_TRUNC):
- raise NotImplementedError
+ d = defer.succeed(None)
+ for f in files:
+ if f is not ignore:
+ d.addBoth(f.sync)
+
+ def _done(ign):
+ self.log("done %r" % (request,), level=OPERATIONAL)
+ return None
+ d.addBoth(_done)
+ return d
+
+ def _remove_heisenfile(self, userpath, parent, childname, file_to_remove):
+ if noisy: self.log("._remove_heisenfile(%r, %r, %r, %r)" % (userpath, parent, childname, file_to_remove), level=NOISY)
+
+ _assert(isinstance(userpath, str) and isinstance(childname, (unicode, NoneType)),
+ userpath=userpath, childname=childname)
+
+ direntry = _direntry_for(parent, childname)
+ if direntry in all_heisenfiles:
+ all_old_files = all_heisenfiles[direntry]
+ all_new_files = [f for f in all_old_files if f is not file_to_remove]
+ if len(all_new_files) > 0:
+ all_heisenfiles[direntry] = all_new_files
+ else:
+ del all_heisenfiles[direntry]
+
+ if userpath in self._heisenfiles:
+ old_files = self._heisenfiles[userpath]
+ new_files = [f for f in old_files if f is not file_to_remove]
+ if len(new_files) > 0:
+ self._heisenfiles[userpath] = new_files
+ else:
+ del self._heisenfiles[userpath]
+
+ if noisy: self.log("all_heisenfiles = %r\nself._heisenfiles = %r" % (all_heisenfiles, self._heisenfiles), level=NOISY)
+
+ def _make_file(self, existing_file, userpath, flags, parent=None, childname=None, filenode=None, metadata=None):
+ if noisy: self.log("._make_file(%r, %r, %r = %r, parent=%r, childname=%r, filenode=%r, metadata=%r)" %
+ (existing_file, userpath, flags, _repr_flags(flags), parent, childname, filenode, metadata),
+ level=NOISY)
+
+ _assert((isinstance(userpath, str) and isinstance(childname, (unicode, NoneType)) and
+ (metadata is None or 'no-write' in metadata)),
+ userpath=userpath, childname=childname, metadata=metadata)
+
+ writing = (flags & (FXF_WRITE | FXF_CREAT)) != 0
+ direntry = _direntry_for(parent, childname, filenode)
+
+ d = self._sync_heisenfiles(userpath, direntry, ignore=existing_file)
+
+ if not writing and (flags & FXF_READ) and filenode and not filenode.is_mutable() and filenode.get_size() <= SIZE_THRESHOLD:
+ d.addCallback(lambda ign: ShortReadOnlySFTPFile(userpath, filenode, metadata))
+ else:
+ close_notify = None
+ if writing:
+ close_notify = self._remove_heisenfile
+
+ d.addCallback(lambda ign: existing_file or GeneralSFTPFile(userpath, flags, close_notify, self._convergence))
+ def _got_file(file):
+ file.open(parent=parent, childname=childname, filenode=filenode, metadata=metadata)
+ if writing:
+ self._add_heisenfile_by_direntry(file)
+ return file
+ d.addCallback(_got_file)
+ return d
+
+ def openFile(self, pathstring, flags, attrs, delay=None):
+ request = ".openFile(%r, %r = %r, %r, delay=%r)" % (pathstring, flags, _repr_flags(flags), attrs, delay)
+ self.log(request, level=OPERATIONAL)
+
+ # This is used for both reading and writing.
+ # First exclude invalid combinations of flags, and empty paths.
+
+ if not (flags & (FXF_READ | FXF_WRITE)):
+ def _bad_readwrite():
+ raise SFTPError(FX_BAD_MESSAGE, "invalid file open flags: at least one of FXF_READ and FXF_WRITE must be set")
+ return defer.execute(_bad_readwrite)
+
+ if (flags & FXF_EXCL) and not (flags & FXF_CREAT):
+ def _bad_exclcreat():
+ raise SFTPError(FX_BAD_MESSAGE, "invalid file open flags: FXF_EXCL cannot be set without FXF_CREAT")
+ return defer.execute(_bad_exclcreat)
+
+ path = self._path_from_string(pathstring)
+ if not path:
+ def _emptypath(): raise SFTPError(FX_NO_SUCH_FILE, "path cannot be empty")
+ return defer.execute(_emptypath)
+
+ # The combination of flags is potentially valid.
+
+ # To work around clients that have race condition bugs, a getAttr, rename, or
+ # remove request following an 'open' request with FXF_WRITE or FXF_CREAT flags,
+ # should succeed even if the 'open' request has not yet completed. So we now
+ # synchronously add a file object into the self._heisenfiles dict, indexed
+ # by its UTF-8 userpath. (We can't yet add it to the all_heisenfiles dict,
+ # because we don't yet have a user-independent path for the file.) The file
+ # object does not know its filenode, parent, or childname at this point.
+
+ userpath = self._path_to_utf8(path)
+
+ if flags & (FXF_WRITE | FXF_CREAT):
+ file = GeneralSFTPFile(userpath, flags, self._remove_heisenfile, self._convergence)
+ self._add_heisenfile_by_path(file)
+ else:
+ # We haven't decided which file implementation to use yet.
+ file = None
+
+ desired_metadata = _attrs_to_metadata(attrs)
+
+ # Now there are two major cases:
+ #
+ # 1. The path is specified as /uri/FILECAP, with no parent directory.
+ # If the FILECAP is mutable and writeable, then we can open it in write-only
+ # or read/write mode (non-exclusively), otherwise we can only open it in
+ # read-only mode. The open should succeed immediately as long as FILECAP is
+ # a valid known filecap that grants the required permission.
+ #
+ # 2. The path is specified relative to a parent. We find the parent dirnode and
+ # get the child's URI and metadata if it exists. There are four subcases:
+ # a. the child does not exist: FXF_CREAT must be set, and we must be able
+ # to write to the parent directory.
+ # b. the child exists but is not a valid known filecap: fail
+ # c. the child is mutable: if we are trying to open it write-only or
+ # read/write, then we must be able to write to the file.
+ # d. the child is immutable: if we are trying to open it write-only or
+ # read/write, then we must be able to write to the parent directory.
+ #
+ # To reduce latency, open normally succeeds as soon as these conditions are
+ # met, even though there might be a failure in downloading the existing file
+ # or uploading a new one. However, there is an exception: if a file has been
+ # written, then closed, and is now being reopened, then we have to delay the
+ # open until the previous upload/publish has completed. This is necessary
+ # because sshfs does not wait for the result of an FXF_CLOSE message before
+ # reporting to the client that a file has been closed. It applies both to
+ # mutable files, and to directory entries linked to an immutable file.
+ #
+ # Note that the permission checks below are for more precise error reporting on
+ # the open call; later operations would fail even if we did not make these checks.
+
+ d = delay or defer.succeed(None)
+ d.addCallback(lambda ign: self._get_root(path))
+ def _got_root( (root, path) ):
+ if root.is_unknown():
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot open an unknown cap (or child of an unknown object). "
+ "Upgrading the gateway to a later Tahoe-LAFS version may help")
if not path:
- raise PermissionError("cannot STOR to root directory")
- childname = path[-1]
- d = self._get_root(path)
- def _got_root((root, path)):
- if not path:
- raise PermissionError("cannot STOR to root directory")
- return root.get_child_at_path(path[:-1])
- d.addCallback(_got_root)
- def _got_parent(parent):
- return WriteFile(parent, childname, self.convergence)
- d.addCallback(_got_parent)
- return d
- raise NotImplementedError
+ # case 1
+ if noisy: self.log("case 1: root = %r, path[:-1] = %r" % (root, path[:-1]), level=NOISY)
+ if not IFileNode.providedBy(root):
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot open a directory cap")
+ if (flags & FXF_WRITE) and root.is_readonly():
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot write to a non-writeable filecap without a parent directory")
+ if flags & FXF_EXCL:
+ raise SFTPError(FX_FAILURE,
+ "cannot create a file exclusively when it already exists")
+
+ # The file does not need to be added to all_heisenfiles, because it is not
+ # associated with a directory entry that needs to be updated.
+
+ metadata = update_metadata(None, desired_metadata, time())
+
+ # We have to decide what to pass for the 'parent_readonly' argument to _no_write,
+ # given that we don't actually have a parent. This only affects the permissions
+ # reported by a getAttrs on this file handle in the case of an immutable file.
+ # We choose 'parent_readonly=True' since that will cause the permissions to be
+ # reported as r--r--r--, which is appropriate because an immutable file can't be
+ # written via this path.
+
+ metadata['no-write'] = _no_write(True, root)
+ return self._make_file(file, userpath, flags, filenode=root, metadata=metadata)
+ else:
+ # case 2
+ childname = path[-1]
+
+ if noisy: self.log("case 2: root = %r, childname = %r, desired_metadata = %r, path[:-1] = %r" %
+ (root, childname, desired_metadata, path[:-1]), level=NOISY)
+ d2 = root.get_child_at_path(path[:-1])
+ def _got_parent(parent):
+ if noisy: self.log("_got_parent(%r)" % (parent,), level=NOISY)
+ if parent.is_unknown():
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot open a child of an unknown object. "
+ "Upgrading the gateway to a later Tahoe-LAFS version may help")
- def removeFile(self, path):
- print "REMOVEFILE", path
- path = self._convert_sftp_path(path)
- return self._remove_thing(path, must_be_file=True)
+ parent_readonly = parent.is_readonly()
+ d3 = defer.succeed(None)
+ if flags & FXF_EXCL:
+ # FXF_EXCL means that the link to the file (not the file itself) must
+ # be created atomically wrt updates by this storage client.
+ # That is, we need to create the link before returning success to the
+ # SFTP open request (and not just on close, as would normally be the
+ # case). We make the link initially point to a zero-length LIT file,
+ # which is consistent with what might happen on a POSIX filesystem.
+
+ if parent_readonly:
+ raise SFTPError(FX_FAILURE,
+ "cannot create a file exclusively when the parent directory is read-only")
+
+ # 'overwrite=False' ensures failure if the link already exists.
+ # FIXME: should use a single call to set_uri and return (child, metadata) (#1035)
+
+ zero_length_lit = "URI:LIT:"
+ if noisy: self.log("%r.set_uri(%r, None, readcap=%r, overwrite=False)" %
+ (parent, zero_length_lit, childname), level=NOISY)
+ d3.addCallback(lambda ign: parent.set_uri(childname, None, readcap=zero_length_lit,
+ metadata=desired_metadata, overwrite=False))
+ def _seturi_done(child):
+ if noisy: self.log("%r.get_metadata_for(%r)" % (parent, childname), level=NOISY)
+ d4 = parent.get_metadata_for(childname)
+ d4.addCallback(lambda metadata: (child, metadata))
+ return d4
+ d3.addCallback(_seturi_done)
+ else:
+ if noisy: self.log("%r.get_child_and_metadata(%r)" % (parent, childname), level=NOISY)
+ d3.addCallback(lambda ign: parent.get_child_and_metadata(childname))
+
+ def _got_child( (filenode, current_metadata) ):
+ if noisy: self.log("_got_child( (%r, %r) )" % (filenode, current_metadata), level=NOISY)
+
+ metadata = update_metadata(current_metadata, desired_metadata, time())
+
+ # Ignore the permissions of the desired_metadata in an open call. The permissions
+ # can only be set by setAttrs.
+ metadata['no-write'] = _no_write(parent_readonly, filenode, current_metadata)
+
+ if filenode.is_unknown():
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot open an unknown cap. Upgrading the gateway "
+ "to a later Tahoe-LAFS version may help")
+ if not IFileNode.providedBy(filenode):
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot open a directory as if it were a file")
+ if (flags & FXF_WRITE) and metadata['no-write']:
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot open a non-writeable file for writing")
+
+ return self._make_file(file, userpath, flags, parent=parent, childname=childname,
+ filenode=filenode, metadata=metadata)
+ def _no_child(f):
+ if noisy: self.log("_no_child(%r)" % (f,), level=NOISY)
+ f.trap(NoSuchChildError)
+
+ if not (flags & FXF_CREAT):
+ raise SFTPError(FX_NO_SUCH_FILE,
+ "the file does not exist, and was not opened with the creation (CREAT) flag")
+ if parent_readonly:
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot create a file when the parent directory is read-only")
+
+ return self._make_file(file, userpath, flags, parent=parent, childname=childname)
+ d3.addCallbacks(_got_child, _no_child)
+ return d3
+
+ d2.addCallback(_got_parent)
+ return d2
+
+ d.addCallback(_got_root)
+ def _remove_on_error(err):
+ if file:
+ self._remove_heisenfile(userpath, None, None, file)
+ return err
+ d.addErrback(_remove_on_error)
+ d.addBoth(_convert_error, request)
+ return d
+
+ def renameFile(self, from_pathstring, to_pathstring, overwrite=False):
+ request = ".renameFile(%r, %r)" % (from_pathstring, to_pathstring)
+ self.log(request, level=OPERATIONAL)
+
+ from_path = self._path_from_string(from_pathstring)
+ to_path = self._path_from_string(to_pathstring)
+ from_userpath = self._path_to_utf8(from_path)
+ to_userpath = self._path_to_utf8(to_path)
- def renameFile(self, oldpath, newpath):
- print "RENAMEFILE", oldpath, newpath
- fromPath = self._convert_sftp_path(oldpath)
- toPath = self._convert_sftp_path(newpath)
# the target directory must already exist
- d = self._get_parent(fromPath)
- def _got_from_parent( (fromparent, childname) ):
- d = self._get_parent(toPath)
- d.addCallback(lambda (toparent, tochildname):
- fromparent.move_child_to(childname,
- toparent, tochildname,
- overwrite=False))
- return d
- d.addCallback(_got_from_parent)
- d.addErrback(self._convert_error)
+ d = deferredutil.gatherResults([self._get_parent_or_node(from_path),
+ self._get_parent_or_node(to_path)])
+ def _got( (from_pair, to_pair) ):
+ if noisy: self.log("_got( (%r, %r) ) in .renameFile(%r, %r, overwrite=%r)" %
+ (from_pair, to_pair, from_pathstring, to_pathstring, overwrite), level=NOISY)
+ (from_parent, from_childname) = from_pair
+ (to_parent, to_childname) = to_pair
+
+ if from_childname is None:
+ raise SFTPError(FX_NO_SUCH_FILE, "cannot rename a source object specified by URI")
+ if to_childname is None:
+ raise SFTPError(FX_NO_SUCH_FILE, "cannot rename to a destination specified by URI")
+
+ # <http://tools.ietf.org/html/draft-ietf-secsh-filexfer-02#section-6.5>
+ # "It is an error if there already exists a file with the name specified
+ # by newpath."
+ # OpenSSH's SFTP server returns FX_PERMISSION_DENIED for this error.
+ #
+ # For the standard SSH_FXP_RENAME operation, overwrite=False.
+ # We also support the posix-rename@openssh.com extension, which uses overwrite=True.
+
+ d2 = defer.succeed(None)
+ if not overwrite:
+ d2.addCallback(lambda ign: to_parent.get(to_childname))
+ def _expect_fail(res):
+ if not isinstance(res, Failure):
+ raise SFTPError(FX_PERMISSION_DENIED, "cannot rename to existing path " + to_userpath)
+
+ # It is OK if we fail for errors other than NoSuchChildError, since that probably
+ # indicates some problem accessing the destination directory.
+ res.trap(NoSuchChildError)
+ d2.addBoth(_expect_fail)
+
+ # If there are heisenfiles to be written at the 'from' direntry, then ensure
+ # they will now be written at the 'to' direntry instead.
+ d2.addCallback(lambda ign:
+ self._rename_heisenfiles(from_userpath, from_parent, from_childname,
+ to_userpath, to_parent, to_childname, overwrite=overwrite))
+
+ def _move(renamed):
+ # FIXME: use move_child_to_path to avoid possible data loss due to #943
+ #d3 = from_parent.move_child_to_path(from_childname, to_root, to_path, overwrite=overwrite)
+
+ d3 = from_parent.move_child_to(from_childname, to_parent, to_childname, overwrite=overwrite)
+ def _check(err):
+ if noisy: self.log("_check(%r) in .renameFile(%r, %r, overwrite=%r)" %
+ (err, from_pathstring, to_pathstring, overwrite), level=NOISY)
+
+ if not isinstance(err, Failure) or (renamed and err.check(NoSuchChildError)):
+ return None
+ if not overwrite and err.check(ExistingChildError):
+ raise SFTPError(FX_PERMISSION_DENIED, "cannot rename to existing path " + to_userpath)
+
+ return err
+ d3.addBoth(_check)
+ return d3
+ d2.addCallback(_move)
+ return d2
+ d.addCallback(_got)
+ d.addBoth(_convert_error, request)
return d
- def makeDirectory(self, path, attrs):
- print "MAKEDIRECTORY", path, attrs
- # TODO: extract attrs["mtime"], use it to set the parent metadata.
- # Maybe also copy attrs["ext_*"] .
- path = self._convert_sftp_path(path)
+ def makeDirectory(self, pathstring, attrs):
+ request = ".makeDirectory(%r, %r)" % (pathstring, attrs)
+ self.log(request, level=OPERATIONAL)
+
+ path = self._path_from_string(pathstring)
+ metadata = _attrs_to_metadata(attrs)
+ if 'no-write' in metadata:
+ def _denied(): raise SFTPError(FX_PERMISSION_DENIED, "cannot create a directory that is initially read-only")
+ return defer.execute(_denied)
+
d = self._get_root(path)
- d.addCallback(lambda (root,path):
- self._get_or_create_directories(root, path))
+ d.addCallback(lambda (root, path):
+ self._get_or_create_directories(root, path, metadata))
+ d.addBoth(_convert_error, request)
return d
- def _get_or_create_directories(self, node, path):
+ def _get_or_create_directories(self, node, path, metadata):
if not IDirectoryNode.providedBy(node):
- # unfortunately it is too late to provide the name of the
- # blocking directory in the error message.
- raise ExistingChildError("cannot create directory because there "
- "is a file in the way") # close enough
+ # TODO: provide the name of the blocking file in the error message.
+ def _blocked(): raise SFTPError(FX_FAILURE, "cannot create directory because there "
+ "is a file in the way") # close enough
+ return defer.execute(_blocked)
+
if not path:
return defer.succeed(node)
d = node.get(path[0])
def _maybe_create(f):
f.trap(NoSuchChildError)
- return node.create_empty_directory(path[0])
+ return node.create_subdirectory(path[0])
d.addErrback(_maybe_create)
- d.addCallback(self._get_or_create_directories, path[1:])
+ d.addCallback(self._get_or_create_directories, path[1:], metadata)
return d
- def removeDirectory(self, path):
- print "REMOVEDIRECTORY", path
- path = self._convert_sftp_path(path)
- return self._remove_thing(path, must_be_directory=True)
-
- def _remove_thing(self, path, must_be_directory=False, must_be_file=False):
- d = defer.maybeDeferred(self._get_parent, path)
- def _convert_error(f):
- f.trap(NoParentError)
- raise PermissionError("cannot delete root directory")
- d.addErrback(_convert_error)
+ def removeFile(self, pathstring):
+ request = ".removeFile(%r)" % (pathstring,)
+ self.log(request, level=OPERATIONAL)
+
+ path = self._path_from_string(pathstring)
+ d = self._remove_object(path, must_be_file=True)
+ d.addBoth(_convert_error, request)
+ return d
+
+ def removeDirectory(self, pathstring):
+ request = ".removeDirectory(%r)" % (pathstring,)
+ self.log(request, level=OPERATIONAL)
+
+ path = self._path_from_string(pathstring)
+ d = self._remove_object(path, must_be_directory=True)
+ d.addBoth(_convert_error, request)
+ return d
+
+ def _remove_object(self, path, must_be_directory=False, must_be_file=False):
+ userpath = self._path_to_utf8(path)
+ d = self._get_parent_or_node(path)
def _got_parent( (parent, childname) ):
- d = parent.get(childname)
- def _got_child(child):
- if must_be_directory and not IDirectoryNode.providedBy(child):
- raise BadRemoveRequest("rmdir called on a file")
- if must_be_file and IDirectoryNode.providedBy(child):
- raise BadRemoveRequest("rmfile called on a directory")
- return parent.delete(childname)
- d.addCallback(_got_child)
- d.addErrback(self._convert_error)
- return d
+ if childname is None:
+ raise SFTPError(FX_NO_SUCH_FILE, "cannot remove an object specified by URI")
+
+ direntry = _direntry_for(parent, childname)
+ d2 = defer.succeed(False)
+ if not must_be_directory:
+ d2.addCallback(lambda ign: self._abandon_any_heisenfiles(userpath, direntry))
+
+ d2.addCallback(lambda abandoned:
+ parent.delete(childname, must_exist=not abandoned,
+ must_be_directory=must_be_directory, must_be_file=must_be_file))
+ return d2
d.addCallback(_got_parent)
return d
+ def openDirectory(self, pathstring):
+ request = ".openDirectory(%r)" % (pathstring,)
+ self.log(request, level=OPERATIONAL)
- def openDirectory(self, path):
- print "OPENDIRECTORY", path
- path = self._convert_sftp_path(path)
- d = self._get_node_and_metadata_for_path(path)
- d.addCallback(lambda (dirnode,metadata): dirnode.list())
- def _render(children):
- results = []
- for filename, (node, metadata) in children.iteritems():
- s = FakeStat()
- if IDirectoryNode.providedBy(node):
- s.st_mode = 040700
- s.st_size = 0
- else:
- s.st_mode = 0100600
- s.st_size = node.get_size()
- s.st_nlink = 1
- s.st_uid = 0
- s.st_gid = 0
- s.st_mtime = int(metadata.get("mtime", 0))
- longname = ls.lsLine(filename.encode("utf-8"), s)
- attrs = self._populate_attrs(node, metadata)
- results.append( (filename.encode("utf-8"), longname, attrs) )
- return StoppableList(results)
- d.addCallback(_render)
+ path = self._path_from_string(pathstring)
+ d = self._get_parent_or_node(path)
+ def _got_parent_or_node( (parent_or_node, childname) ):
+ if noisy: self.log("_got_parent_or_node( (%r, %r) ) in openDirectory(%r)" %
+ (parent_or_node, childname, pathstring), level=NOISY)
+ if childname is None:
+ return parent_or_node
+ else:
+ return parent_or_node.get(childname)
+ d.addCallback(_got_parent_or_node)
+ def _list(dirnode):
+ if dirnode.is_unknown():
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot list an unknown cap as a directory. Upgrading the gateway "
+ "to a later Tahoe-LAFS version may help")
+ if not IDirectoryNode.providedBy(dirnode):
+ raise SFTPError(FX_PERMISSION_DENIED,
+ "cannot list a file as if it were a directory")
+
+ d2 = dirnode.list()
+ def _render(children):
+ parent_readonly = dirnode.is_readonly()
+ results = []
+ for filename, (child, metadata) in children.iteritems():
+ # The file size may be cached or absent.
+ metadata['no-write'] = _no_write(parent_readonly, child, metadata)
+ attrs = _populate_attrs(child, metadata)
+ filename_utf8 = filename.encode('utf-8')
+ longname = _lsLine(filename_utf8, attrs)
+ results.append( (filename_utf8, longname, attrs) )
+ return StoppableList(results)
+ d2.addCallback(_render)
+ return d2
+ d.addCallback(_list)
+ d.addBoth(_convert_error, request)
return d
- def getAttrs(self, path, followLinks):
- print "GETATTRS", path, followLinks
- # from ftp.stat
- d = self._get_node_and_metadata_for_path(self._convert_sftp_path(path))
- def _render((node,metadata)):
- return self._populate_attrs(node, metadata)
- d.addCallback(_render)
- d.addErrback(self._convert_error)
- def _done(res):
- print " DONE", res
- return res
- d.addBoth(_done)
+ def getAttrs(self, pathstring, followLinks):
+ request = ".getAttrs(%r, followLinks=%r)" % (pathstring, followLinks)
+ self.log(request, level=OPERATIONAL)
+
+ # When asked about a specific file, report its current size.
+ # TODO: the modification time for a mutable file should be
+ # reported as the update time of the best version. But that
+ # information isn't currently stored in mutable shares, I think.
+
+ path = self._path_from_string(pathstring)
+ userpath = self._path_to_utf8(path)
+ d = self._get_parent_or_node(path)
+ def _got_parent_or_node( (parent_or_node, childname) ):
+ if noisy: self.log("_got_parent_or_node( (%r, %r) )" % (parent_or_node, childname), level=NOISY)
+
+ # Some clients will incorrectly try to get the attributes
+ # of a file immediately after opening it, before it has been put
+ # into the all_heisenfiles table. This is a race condition bug in
+ # the client, but we handle it anyway by calling .sync() on all
+ # files matching either the path or the direntry.
+
+ direntry = _direntry_for(parent_or_node, childname)
+ d2 = self._sync_heisenfiles(userpath, direntry)
+
+ if childname is None:
+ node = parent_or_node
+ d2.addCallback(lambda ign: node.get_current_size())
+ d2.addCallback(lambda size:
+ _populate_attrs(node, {'no-write': node.is_unknown() or node.is_readonly()}, size=size))
+ else:
+ parent = parent_or_node
+ d2.addCallback(lambda ign: parent.get_child_and_metadata_at_path([childname]))
+ def _got( (child, metadata) ):
+ if noisy: self.log("_got( (%r, %r) )" % (child, metadata), level=NOISY)
+ _assert(IDirectoryNode.providedBy(parent), parent=parent)
+ metadata['no-write'] = _no_write(parent.is_readonly(), child, metadata)
+ d3 = child.get_current_size()
+ d3.addCallback(lambda size: _populate_attrs(child, metadata, size=size))
+ return d3
+ def _nosuch(err):
+ if noisy: self.log("_nosuch(%r)" % (err,), level=NOISY)
+ err.trap(NoSuchChildError)
+ if noisy: self.log("checking open files:\nself._heisenfiles = %r\nall_heisenfiles = %r\ndirentry=%r" %
+ (self._heisenfiles, all_heisenfiles, direntry), level=NOISY)
+ if direntry in all_heisenfiles:
+ files = all_heisenfiles[direntry]
+ if len(files) == 0: # pragma: no cover
+ return err
+ # use the heisenfile that was most recently opened
+ return files[-1].getAttrs()
+ return err
+ d2.addCallbacks(_got, _nosuch)
+ return d2
+ d.addCallback(_got_parent_or_node)
+ d.addBoth(_convert_error, request)
return d
- def _convert_sftp_path(self, pathstring):
- assert pathstring[0] == "/"
+ def setAttrs(self, pathstring, attrs):
+ request = ".setAttrs(%r, %r)" % (pathstring, attrs)
+ self.log(request, level=OPERATIONAL)
+
+ if "size" in attrs:
+ # this would require us to download and re-upload the truncated/extended
+ # file contents
+ def _unsupported(): raise SFTPError(FX_OP_UNSUPPORTED, "setAttrs wth size attribute unsupported")
+ return defer.execute(_unsupported)
+
+ path = self._path_from_string(pathstring)
+ userpath = self._path_to_utf8(path)
+ d = self._get_parent_or_node(path)
+ def _got_parent_or_node( (parent_or_node, childname) ):
+ if noisy: self.log("_got_parent_or_node( (%r, %r) )" % (parent_or_node, childname), level=NOISY)
+
+ direntry = _direntry_for(parent_or_node, childname)
+ d2 = self._update_attrs_for_heisenfiles(userpath, direntry, attrs)
+
+ def _update(updated_heisenfiles):
+ if childname is None:
+ if updated_heisenfiles:
+ return None
+ raise SFTPError(FX_NO_SUCH_FILE, userpath)
+ else:
+ desired_metadata = _attrs_to_metadata(attrs)
+ if noisy: self.log("desired_metadata = %r" % (desired_metadata,), level=NOISY)
+
+ d3 = parent_or_node.set_metadata_for(childname, desired_metadata)
+ def _nosuch(err):
+ if updated_heisenfiles:
+ err.trap(NoSuchChildError)
+ else:
+ return err
+ d3.addErrback(_nosuch)
+ return d3
+ d2.addCallback(_update)
+ d2.addCallback(lambda ign: None)
+ return d2
+ d.addCallback(_got_parent_or_node)
+ d.addBoth(_convert_error, request)
+ return d
+
+ def readLink(self, pathstring):
+ self.log(".readLink(%r)" % (pathstring,), level=OPERATIONAL)
+
+ def _unsupported(): raise SFTPError(FX_OP_UNSUPPORTED, "readLink")
+ return defer.execute(_unsupported)
+
+ def makeLink(self, linkPathstring, targetPathstring):
+ self.log(".makeLink(%r, %r)" % (linkPathstring, targetPathstring), level=OPERATIONAL)
+
+ # If this is implemented, note the reversal of arguments described in point 7 of
+ # <http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL?rev=1.15>.
+
+ def _unsupported(): raise SFTPError(FX_OP_UNSUPPORTED, "makeLink")
+ return defer.execute(_unsupported)
+
+ def extendedRequest(self, extensionName, extensionData):
+ self.log(".extendedRequest(%r, <data of length %r>)" % (extensionName, len(extensionData)), level=OPERATIONAL)
+
+ # We implement the three main OpenSSH SFTP extensions; see
+ # <http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL?rev=1.15>
+
+ if extensionName == 'posix-rename@openssh.com':
+ def _bad(): raise SFTPError(FX_BAD_MESSAGE, "could not parse posix-rename@openssh.com request")
+
+ if 4 > len(extensionData): return defer.execute(_bad)
+ (fromPathLen,) = struct.unpack('>L', extensionData[0:4])
+ if 8 + fromPathLen > len(extensionData): return defer.execute(_bad)
+
+ (toPathLen,) = struct.unpack('>L', extensionData[(4 + fromPathLen):(8 + fromPathLen)])
+ if 8 + fromPathLen + toPathLen != len(extensionData): return defer.execute(_bad)
+
+ fromPathstring = extensionData[4:(4 + fromPathLen)]
+ toPathstring = extensionData[(8 + fromPathLen):]
+ d = self.renameFile(fromPathstring, toPathstring, overwrite=True)
+
+ # Twisted conch assumes that the response from an extended request is either
+ # an error, or an FXP_EXTENDED_REPLY. But it happens to do the right thing
+ # (respond with an FXP_STATUS message) if we return a Failure with code FX_OK.
+ def _succeeded(ign):
+ raise SFTPError(FX_OK, "request succeeded")
+ d.addCallback(_succeeded)
+ return d
+
+ if extensionName == 'statvfs@openssh.com' or extensionName == 'fstatvfs@openssh.com':
+ # f_bsize and f_frsize should be the same to avoid a bug in 'df'
+ return defer.succeed(struct.pack('>11Q',
+ 1024, # uint64 f_bsize /* file system block size */
+ 1024, # uint64 f_frsize /* fundamental fs block size */
+ 628318530, # uint64 f_blocks /* number of blocks (unit f_frsize) */
+ 314159265, # uint64 f_bfree /* free blocks in file system */
+ 314159265, # uint64 f_bavail /* free blocks for non-root */
+ 200000000, # uint64 f_files /* total file inodes */
+ 100000000, # uint64 f_ffree /* free file inodes */
+ 100000000, # uint64 f_favail /* free file inodes for non-root */
+ 0x1AF5, # uint64 f_fsid /* file system id */
+ 2, # uint64 f_flag /* bit mask = ST_NOSUID; not ST_RDONLY */
+ 65535, # uint64 f_namemax /* maximum filename length */
+ ))
+
+ def _unsupported(): raise SFTPError(FX_OP_UNSUPPORTED, "unsupported %r request <data of length %r>" %
+ (extensionName, len(extensionData)))
+ return defer.execute(_unsupported)
+
+ def realPath(self, pathstring):
+ self.log(".realPath(%r)" % (pathstring,), level=OPERATIONAL)
+
+ return self._path_to_utf8(self._path_from_string(pathstring))
+
+ def _path_to_utf8(self, path):
+ return (u"/" + u"/".join(path)).encode('utf-8')
+
+ def _path_from_string(self, pathstring):
+ if noisy: self.log("CONVERT %r" % (pathstring,), level=NOISY)
+
+ _assert(isinstance(pathstring, str), pathstring=pathstring)
+
+ # The home directory is the root directory.
pathstring = pathstring.strip("/")
- if pathstring == "":
- path = []
+ if pathstring == "" or pathstring == ".":
+ path_utf8 = []
else:
- path = pathstring.split("/")
- print "CONVERT", pathstring, path
- path = [unicode(p) for p in path]
+ path_utf8 = pathstring.split("/")
+
+ # <http://tools.ietf.org/html/draft-ietf-secsh-filexfer-02#section-6.2>
+ # "Servers SHOULD interpret a path name component ".." as referring to
+ # the parent directory, and "." as referring to the current directory."
+ path = []
+ for p_utf8 in path_utf8:
+ if p_utf8 == "..":
+ # ignore excess .. components at the root
+ if len(path) > 0:
+ path = path[:-1]
+ elif p_utf8 != ".":
+ try:
+ p = p_utf8.decode('utf-8', 'strict')
+ except UnicodeError:
+ raise SFTPError(FX_NO_SUCH_FILE, "path could not be decoded as UTF-8")
+ path.append(p)
+
+ if noisy: self.log(" PATH %r" % (path,), level=NOISY)
return path
- def _get_node_and_metadata_for_path(self, path):
+ def _get_root(self, path):
+ # return Deferred (root, remaining_path)
+ d = defer.succeed(None)
+ if path and path[0] == u"uri":
+ d.addCallback(lambda ign: self._client.create_node_from_uri(path[1].encode('utf-8')))
+ d.addCallback(lambda root: (root, path[2:]))
+ else:
+ d.addCallback(lambda ign: (self._root, path))
+ return d
+
+ def _get_parent_or_node(self, path):
+ # return Deferred (parent, childname) or (node, None)
d = self._get_root(path)
- def _got_root((root,path)):
- print "ROOT", root
- print "PATH", path
- if path:
- return root.get_child_and_metadata_at_path(path)
+ def _got_root( (root, remaining_path) ):
+ if not remaining_path:
+ return (root, None)
else:
- return (root,{})
+ d2 = root.get_child_at_path(remaining_path[:-1])
+ d2.addCallback(lambda parent: (parent, remaining_path[-1]))
+ return d2
d.addCallback(_got_root)
return d
- def _get_root(self, path):
- # return (root, remaining_path)
- path = [unicode(p) for p in path]
- if path and path[0] == "uri":
- d = defer.maybeDeferred(self.client.create_node_from_uri,
- str(path[1]))
- d.addCallback(lambda root: (root, path[2:]))
+
+class FakeTransport:
+ implements(ITransport)
+ def write(self, data):
+ logmsg("FakeTransport.write(<data of length %r>)" % (len(data),), level=NOISY)
+
+ def writeSequence(self, data):
+ logmsg("FakeTransport.writeSequence(...)", level=NOISY)
+
+ def loseConnection(self):
+ logmsg("FakeTransport.loseConnection()", level=NOISY)
+
+ # getPeer and getHost can just raise errors, since we don't know what to return
+
+
+class ShellSession(PrefixingLogMixin):
+ implements(ISession)
+ def __init__(self, userHandler):
+ PrefixingLogMixin.__init__(self, facility="tahoe.sftp")
+ if noisy: self.log(".__init__(%r)" % (userHandler), level=NOISY)
+
+ def getPty(self, terminal, windowSize, attrs):
+ self.log(".getPty(%r, %r, %r)" % (terminal, windowSize, attrs), level=OPERATIONAL)
+
+ def openShell(self, protocol):
+ self.log(".openShell(%r)" % (protocol,), level=OPERATIONAL)
+ if hasattr(protocol, 'transport') and protocol.transport is None:
+ protocol.transport = FakeTransport() # work around Twisted bug
+
+ return self._unsupported(protocol)
+
+ def execCommand(self, protocol, cmd):
+ self.log(".execCommand(%r, %r)" % (protocol, cmd), level=OPERATIONAL)
+ if hasattr(protocol, 'transport') and protocol.transport is None:
+ protocol.transport = FakeTransport() # work around Twisted bug
+
+ d = defer.succeed(None)
+ if cmd == "df -P -k /":
+ d.addCallback(lambda ign: protocol.write(
+ "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 = defer.succeed((self.root,path))
+ d.addCallback(lambda ign: self._unsupported(protocol))
return d
- def _populate_attrs(self, childnode, metadata):
- attrs = {}
- attrs["uid"] = 1000
- attrs["gid"] = 1000
- attrs["atime"] = 0
- attrs["mtime"] = int(metadata.get("mtime", 0))
- isdir = bool(IDirectoryNode.providedBy(childnode))
- if isdir:
- attrs["size"] = 1
- # the permissions must have the extra bits (040000 or 0100000),
- # otherwise the client will not call openDirectory
- attrs["permissions"] = 040700 # S_IFDIR
- else:
- attrs["size"] = childnode.get_size()
- attrs["permissions"] = 0100600 # S_IFREG
- return attrs
-
- def _convert_error(self, f):
- if f.check(NoSuchChildError):
- childname = f.value.args[0].encode("utf-8")
- raise SFTPError(FX_NO_SUCH_FILE, childname)
- if f.check(ExistingChildError):
- msg = f.value.args[0].encode("utf-8")
- raise SFTPError(FX_FILE_ALREADY_EXISTS, msg)
- if f.check(PermissionError):
- raise SFTPError(FX_PERMISSION_DENIED, str(f.value))
- if f.check(NotImplementedError):
- raise SFTPError(FX_OP_UNSUPPORTED, str(f.value))
- return f
-
-
- def setAttrs(self, path, attrs):
- print "SETATTRS", path, attrs
- # ignored
- return None
-
- def readLink(self, path):
- print "READLINK", path
- raise NotImplementedError
-
- def makeLink(self, linkPath, targetPath):
- print "MAKELINK", linkPath, targetPath
- raise NotImplementedError
-
- def extendedRequest(self, extendedName, extendedData):
- print "EXTENDEDREQUEST", extendedName, extendedData
- # client 'df' command requires 'statvfs@openssh.com' extension
- raise NotImplementedError
- def realPath(self, path):
- print "REALPATH", path
- if path == ".":
- return "/"
- return path
+ 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):
+ self.log(".windowChanged(%r)" % (newWindowSize,), level=OPERATIONAL)
- def _get_parent(self, path):
- # fire with (parentnode, childname)
- path = [unicode(p) for p in path]
- if not path:
- raise NoParentError
- childname = path[-1]
- d = self._get_root(path)
- def _got_root((root, path)):
- if not path:
- raise NoParentError
- return root.get_child_at_path(path[:-1])
- d.addCallback(_got_root)
- def _got_parent(parent):
- return (parent, childname)
- d.addCallback(_got_parent)
- return d
+ def eofReceived(self):
+ self.log(".eofReceived()", level=OPERATIONAL)
+
+ def closed(self):
+ self.log(".closed()", level=OPERATIONAL)
-# if you have an SFTPUser, and you want something that provides ISFTPServer,
-# then you get SFTPHandler(user)
-components.registerAdapter(SFTPHandler, SFTPUser, ISFTPServer)
+# If you have an SFTPUserHandler and want something that provides ISession, you get
+# ShellSession(userHandler).
+# We use adaptation because this must be a different object to the SFTPUserHandler.
+components.registerAdapter(ShellSession, SFTPUserHandler, ISession)
-from auth import AccountURLChecker, AccountFileChecker, NeedRootcapLookupScheme
+
+from allmydata.frontends.auth import AccountURLChecker, AccountFileChecker, NeedRootcapLookupScheme
class Dispatcher:
implements(portal.IRealm)
def __init__(self, client):
- self.client = client
+ self._client = client
def requestAvatar(self, avatarID, mind, interface):
- assert interface == IConchUser
- rootnode = self.client.create_node_from_uri(avatarID.rootcap)
- convergence = self.client.convergence
- s = SFTPUser(self.client, rootnode, avatarID.username, convergence)
- def logout(): pass
- return (interface, s, logout)
+ _assert(interface == IConchUser, interface=interface)
+ rootnode = self._client.create_node_from_uri(avatarID.rootcap)
+ handler = SFTPUserHandler(self._client, rootnode, avatarID.username)
+ return (interface, handler, handler.logout)
+
class SFTPServer(service.MultiService):
def __init__(self, client, accountfile, accounturl,
sftp_portstr, pubkey_file, privkey_file):
+ precondition(isinstance(accountfile, unicode), accountfile)
+ precondition(isinstance(pubkey_file, unicode), pubkey_file)
+ precondition(isinstance(privkey_file, unicode), privkey_file)
service.MultiService.__init__(self)
r = Dispatcher(client)
p.registerChecker(c)
if not accountfile and not accounturl:
# we could leave this anonymous, with just the /uri/CAP form
- raise NeedRootcapLookupScheme("must provide some translation")
+ raise NeedRootcapLookupScheme("must provide an account file or URL")
- pubkey = keys.Key.fromFile(pubkey_file)
- privkey = keys.Key.fromFile(privkey_file)
+ pubkey = keys.Key.fromFile(pubkey_file.encode(get_filesystem_encoding()))
+ privkey = keys.Key.fromFile(privkey_file.encode(get_filesystem_encoding()))
class SSHFactory(factory.SSHFactory):
publicKeys = {pubkey.sshType(): pubkey}
privateKeys = {privkey.sshType(): privkey}
s = strports.service(sftp_portstr, f)
s.setServiceParent(self)
-